CHICAGO, Ill. (February 4, 2010) — In a study to be presented today at the Society for Maternal-Fetal Medicine's (SMFM) annual meeting, The Pregnancy Meeting ™, in Chicago, researchers will unveil findings that show that acupuncture may be an effective treatment for depression during pregnancy.
"Depression during pregnancy is an issue of concern because it has negative effects on both the mother and the baby as well as the rest of the family," said Dr. Schnyer, one of the study's authors.
About 10% of pregnant women meet criteria for major depression and almost 20% have increased symptoms of depression during pregnancy. The rates of depression in pregnant women are comparable to rates seen among similarly aged non-pregnant women and among women during the postpartum period, but there are far fewer treatment studies of depression during pregnancy than during the postpartum period.
Dealing with depression is difficult for pregnant women because the use of anti-depressants poses concerns to the developing fetus and women are reluctant to take medications during pregnancy.
In the study, an evaluator-blinded randomized trial, 150 participants who met the Diagnostic & Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria for Major Depressive Disorder were randomized to receive either acupuncture specific for depression (SPEC, n=52) or one of two active controls: control acupuncture (CTRL, n=49) or massage (MSSG, n=49). Treatments lasted eight weeks (12 sessions). Junior acupuncturists masked to treatment assignment needled participants at points prescribed by senior acupuncturists. Massage therapists and patients were not blinded. The primary outcome was the Hamilton Rating Scale for Depression, administered by blinded raters at baseline and after four and eight weeks of treatment. Data were analyzed using mixed effects models and by intent-to-treat.
The results showed that the women who received SPEC experienced a significantly greater decrease in depression severity (p<0.05) compared to the combined controls (d=0.39, 95% CI [-1.31, 1.65]) or CTRL acupuncture alone (p<0.05; Cohen´s-d = 0.46, 95% CI [-1.24, 2.31]). They also had a higher response rate (63.0%) than the combined controls (44.3%; p<.05; NNT=5.3, 95% CI [2.8, 75.0]) or CTRL acupuncture alone (37.5%; p<0.05; NNT=3.9, 95% CI [2.2, 19.8]). Symptom reduction and response rates did not differ significantly between controls (CTRL 37.5% and MSSG 50.0%). Mild and transient side effects were reported by 43/150 participants (4 in MSSG; 19 in CTRL, 20 in SPEC). Significantly fewer participants reported side-effects in MSSG than the two acupuncture groups (p<0.01).
"The results of our study show that the acupuncture protocol we tested could be a viable treatment option for depression during pregnancy" said Dr. Schnyer.
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5 February 2010
Plant derivative could help refine cancer treatment
AUGUSTA, Ga. – Medical College of Georgia researchers are seeking to refine cancer treatment with an anti-inflammatory plant derivative long used in Chinese medicine.
Celastrol, derived from trees and shrubs called celastracaea, has been used for centuries in China to treat symptoms such as fever, chills, joint pain and inflammation. The MCG researchers think it may also play a role in cancer treatment by inactivating a protein required for cancer growth.
That protein, P23, is one of many proteins helping the heat shock protein 90. Scientists are just beginning to realize the potential of controlling inflammation-related diseases, including cancer, by inhibiting HSP90.
"Cancer cells need HSP90 more than normal cells because cancer cells have thousands of mutations," said Dr. Ahmed Chadli, biochemist in the MCG Center for Molecular Chaperones/Radiobiology and Cancer Virology. "They need chaperones all the time to keep their mutated proteins active. By taking heat shock proteins away from cells, the stabilization is taken away and cell death occurs."
But most HSP90 inhibitors lack selectivity, disabling the functions of all proteins activated by HSP90 rather than only the ones implicated in a specific tumor. Those proteins vary from one tumor to another.
Dr. Chadli and colleagues at the Mayo Clinic believe celastrol holds the key to specificity, targeting the HSP90-activated protein required for folding steroid receptors.
"The celastrol induces the protein to form fibrils and clusters it together, which inactivates it," said Dr. Chadli, whose research was published in the January edition of The Journal of Biological Chemistry. "When they are clustered, they're not available for other functions that help cancer grow."
The research was funded by a seed grant from the MCG Cardiovascular Discovery Institute and a Scientist Development Grant from The American Heart Association.
Dr. Chadli envisions future studies on cancer patients using even more potent derivatives of celastrol.
"They can hopefully be used in combination with other therapeutic agents to reduce the probability of cancer resistance," he said.
Celastrol, derived from trees and shrubs called celastracaea, has been used for centuries in China to treat symptoms such as fever, chills, joint pain and inflammation. The MCG researchers think it may also play a role in cancer treatment by inactivating a protein required for cancer growth.
That protein, P23, is one of many proteins helping the heat shock protein 90. Scientists are just beginning to realize the potential of controlling inflammation-related diseases, including cancer, by inhibiting HSP90.
"Cancer cells need HSP90 more than normal cells because cancer cells have thousands of mutations," said Dr. Ahmed Chadli, biochemist in the MCG Center for Molecular Chaperones/Radiobiology and Cancer Virology. "They need chaperones all the time to keep their mutated proteins active. By taking heat shock proteins away from cells, the stabilization is taken away and cell death occurs."
But most HSP90 inhibitors lack selectivity, disabling the functions of all proteins activated by HSP90 rather than only the ones implicated in a specific tumor. Those proteins vary from one tumor to another.
Dr. Chadli and colleagues at the Mayo Clinic believe celastrol holds the key to specificity, targeting the HSP90-activated protein required for folding steroid receptors.
"The celastrol induces the protein to form fibrils and clusters it together, which inactivates it," said Dr. Chadli, whose research was published in the January edition of The Journal of Biological Chemistry. "When they are clustered, they're not available for other functions that help cancer grow."
The research was funded by a seed grant from the MCG Cardiovascular Discovery Institute and a Scientist Development Grant from The American Heart Association.
Dr. Chadli envisions future studies on cancer patients using even more potent derivatives of celastrol.
"They can hopefully be used in combination with other therapeutic agents to reduce the probability of cancer resistance," he said.
Vitamin B6 may affect heart disease risk: Study
Low levels of vitamin B6 may increase the risk of inflammation and metabolic conditions, and subsequently cardiovascular disease risk, says a new study.
A cross-sectional study with 1,205 people found that higher levels of pyridoxal-5'-phosphate (PLP), the active form of vitamin B6, were linked to lower levels of C-reactive protein (CRP), a marker of inflammation, as well as lower levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker for oxidative stress, both of which are related to heart disease risk.
CRP is produced in the liver and is a known marker for inflammation. Increased levels of CRP are a good predictor for the onset of both type-2 diabetes and cardiovascular disease. CVD causes almost 50 per cent of deaths in Europe, and is reported to cost the EU economy an estimated €169 billion ($202 billion) per year.
Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University report their findings in the American Journal of Clinical Nutrition.
“Our data suggest that vitamin B-6 may influence cardiovascular disease risk through mechanisms other than [reduction of the amino acid] homocysteine and support the notion that nutritional status may influence the health disparities present in this population,” wrote the researchers, led by Jian Shen.
Study details
Shen and co-workers measured levels of PLP, CRP, and 8-OHdG in 1,205 Puerto Rican adults aged between 45 and 75 and living in Massachusetts.
Results showed a strong dose-dependent relationship between PLP levels and CRP levels, with the highest PLP levels associated with CRP levels almost 50 per cent lower than low PLP levels.
Furthermore, the highest average levels of PLP were associated with 8-OHdG concentrations of 108 nanograms per milligram, compared to 124 ng/mg for low PLP levels.
The associations were observed even after the researchers took into account homocysteine levels.
It is not the first time that PLP levels have been linked to CRP levels. A Harvard study reported last year that PLP levels were slightly inversely correlated with blood levels of CRP, and may also reduce the risk of colorectal cancer by 50 per cent (Cancer Epidemiology, Biomarkers & Prevention, Vol. 18, pp. 1197-1202).
A cross-sectional study with 1,205 people found that higher levels of pyridoxal-5'-phosphate (PLP), the active form of vitamin B6, were linked to lower levels of C-reactive protein (CRP), a marker of inflammation, as well as lower levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker for oxidative stress, both of which are related to heart disease risk.
CRP is produced in the liver and is a known marker for inflammation. Increased levels of CRP are a good predictor for the onset of both type-2 diabetes and cardiovascular disease. CVD causes almost 50 per cent of deaths in Europe, and is reported to cost the EU economy an estimated €169 billion ($202 billion) per year.
Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University report their findings in the American Journal of Clinical Nutrition.
“Our data suggest that vitamin B-6 may influence cardiovascular disease risk through mechanisms other than [reduction of the amino acid] homocysteine and support the notion that nutritional status may influence the health disparities present in this population,” wrote the researchers, led by Jian Shen.
Study details
Shen and co-workers measured levels of PLP, CRP, and 8-OHdG in 1,205 Puerto Rican adults aged between 45 and 75 and living in Massachusetts.
Results showed a strong dose-dependent relationship between PLP levels and CRP levels, with the highest PLP levels associated with CRP levels almost 50 per cent lower than low PLP levels.
Furthermore, the highest average levels of PLP were associated with 8-OHdG concentrations of 108 nanograms per milligram, compared to 124 ng/mg for low PLP levels.
The associations were observed even after the researchers took into account homocysteine levels.
It is not the first time that PLP levels have been linked to CRP levels. A Harvard study reported last year that PLP levels were slightly inversely correlated with blood levels of CRP, and may also reduce the risk of colorectal cancer by 50 per cent (Cancer Epidemiology, Biomarkers & Prevention, Vol. 18, pp. 1197-1202).
How pastured organic cows produce a better glass of milk
Pour a tall, creamy glass of cold milk and picture a herd of peaceful cows, grazing happily in a grassy green pasture. Pour a second glass and imagine a long line of cows confined indoors, penned in a long line of cramped stalls with noisy fans blowing air in and out. Food—grain, mostly corn, laced with supplements and medication—is brought to a trough in front of them,; the remains of which they deposit into another trough behind them, where it runs into what's known as the manure pit.
If you're drinking milk from a family farm, your first picture is more likely to be true. But if your milk came from a large commercial dairy, it's almost certain the cows that gave your milk rarely see grass, much less the out-of-doors, and their living conditions look like the second image, or worse. More and more consumers are choosing the kind of farming represented by the first glass of milk. And that means more and more farmers can make the same choice.
Large-scale confinement farms dominate dairy production in the U.S. today. Only 10-15% of U.S. dairy farms are pasture-based, meaning cows are fed primarily outdoors on pasture, rather than indoors on grain. But a growing number of farmers—including Organic Valley farmers—are finding pasture-based farming can also mean healthier cows, more nutritious dairy products, profitable family farms and sustainable land stewardship. Like forward-thinking farmers in New Zealand, Ireland and elsewhere, they are turning to pasturing as the preferred way to farm.
Pasturing methods are a good fit with organic farming, but organic does not always mean pastured. USDA Organic standards require "access to pasture" as part of an organic livestock system. This minimum standard does not specify how often or how long cows are outdoors, nor does it require they be fed live grasses. The standards permit confinement "as needed" for weather and "stage of production," leaving considerable leeway for cows to be kept indoors and fed grain most of the time.
Some organic farmers would like to see the USDA standards made more strict, to mandate a higher percentage of pasture feeding. There is also a process underway to set USDA labeling standards for 100% grass-fed products. Even if all that happens, it will be difficult for consumers to differentiate certified organic from grass-fed certified organic, with its added benefits. The family farmers of Organic Valley are committed to pasturing as they continue to lead the organic dairy industry, and many of their practices go beyond the minimum standards for organic certification.
Once, nearly all dairy cattle were pasture-raised. That usually meant turning cows out to graze freely, often resulting in overgrazing, trampling and waste. Such practices, along with a surplus of cheap subsidized corn, encouraged the rise of confinement feeding. But it turns out all pasture-based dairy farming is not the same. Methods known as Management Intensive Rotational Grazing (MIRG) or Holistic Resource Management (HRM) offer significant benefits over both confinement and old-style grazing methods and can make pasturing both economical and ecological.
Managed grazing involves dividing a pasture into pens or paddocks, and shifting the cows from paddock to paddock as they graze. Cows are moved based on the condition of the grass—allowing the farmer to avoid overgrazing, giving cows access to pasture at the peak of nutrition and the right height for grazing, and letting the animals spread manure evenly over the entire pasture. Rotation also extends the grazing season, and often produces enough surplus grass during the summer months to provide silage for feed in winter.
After Organic Valley farmer Ernest Martin converted his Ohio farm to pasture, the shift to organic methods required few additional changes. He had already stopped growing corn for feed so he wasn't using synthetic chemicals anyway. He now buys some organic grain to supplement his cows' feed, and has found alternatives to antibiotics. He believes grazing methods are especially important in the organic world. "It's as close to nature as you will find," he says.
If you're drinking milk from a family farm, your first picture is more likely to be true. But if your milk came from a large commercial dairy, it's almost certain the cows that gave your milk rarely see grass, much less the out-of-doors, and their living conditions look like the second image, or worse. More and more consumers are choosing the kind of farming represented by the first glass of milk. And that means more and more farmers can make the same choice.
Large-scale confinement farms dominate dairy production in the U.S. today. Only 10-15% of U.S. dairy farms are pasture-based, meaning cows are fed primarily outdoors on pasture, rather than indoors on grain. But a growing number of farmers—including Organic Valley farmers—are finding pasture-based farming can also mean healthier cows, more nutritious dairy products, profitable family farms and sustainable land stewardship. Like forward-thinking farmers in New Zealand, Ireland and elsewhere, they are turning to pasturing as the preferred way to farm.
Pasturing methods are a good fit with organic farming, but organic does not always mean pastured. USDA Organic standards require "access to pasture" as part of an organic livestock system. This minimum standard does not specify how often or how long cows are outdoors, nor does it require they be fed live grasses. The standards permit confinement "as needed" for weather and "stage of production," leaving considerable leeway for cows to be kept indoors and fed grain most of the time.
Some organic farmers would like to see the USDA standards made more strict, to mandate a higher percentage of pasture feeding. There is also a process underway to set USDA labeling standards for 100% grass-fed products. Even if all that happens, it will be difficult for consumers to differentiate certified organic from grass-fed certified organic, with its added benefits. The family farmers of Organic Valley are committed to pasturing as they continue to lead the organic dairy industry, and many of their practices go beyond the minimum standards for organic certification.
Once, nearly all dairy cattle were pasture-raised. That usually meant turning cows out to graze freely, often resulting in overgrazing, trampling and waste. Such practices, along with a surplus of cheap subsidized corn, encouraged the rise of confinement feeding. But it turns out all pasture-based dairy farming is not the same. Methods known as Management Intensive Rotational Grazing (MIRG) or Holistic Resource Management (HRM) offer significant benefits over both confinement and old-style grazing methods and can make pasturing both economical and ecological.
Managed grazing involves dividing a pasture into pens or paddocks, and shifting the cows from paddock to paddock as they graze. Cows are moved based on the condition of the grass—allowing the farmer to avoid overgrazing, giving cows access to pasture at the peak of nutrition and the right height for grazing, and letting the animals spread manure evenly over the entire pasture. Rotation also extends the grazing season, and often produces enough surplus grass during the summer months to provide silage for feed in winter.
After Organic Valley farmer Ernest Martin converted his Ohio farm to pasture, the shift to organic methods required few additional changes. He had already stopped growing corn for feed so he wasn't using synthetic chemicals anyway. He now buys some organic grain to supplement his cows' feed, and has found alternatives to antibiotics. He believes grazing methods are especially important in the organic world. "It's as close to nature as you will find," he says.
Hibiscus tea may reduce blood pressure in at-risk people
A few cups of hibiscus tea a day may reduce blood pressure and offer cardiovascular benefits for people at risk of developing hypertension, says a new study from Tufts University.
Three 240 mL servings a day of tea made with hibiscus (Hibiscus sabdariffa L.) were associated with a 7.2 mmHg reduction in systolic blood pressure and a 3.1 mmHg reduction in diastolic blood pressure, compared to 1.3 and 0.5 mmHg in the placebo group, according to findings published in The Journal of Nutrition.
Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University report that this is the first placebo-controlled clinical trial to study if hibiscus tea, in an amount easily attained from the diet, may affect blood pressure.
“Hypertension is a major risk factor for cardiovascular disease and is associated with substantial morbidity and mortality, estimated to account for 35 per cent of myocardial infarction and stroke, 49 per cent of heart failure, and 24 per cent of premature mortality,” wrote the researchers, led by Dr Diane McKay.
“The dietary change assessed in this study, i.e. regularly incorporating 3 servings/d of hibiscus tea into the diet, effectively reduces blood pressure in pre- and mildly-hypertensive adults.
“This strategy may be useful in preventing the progression to moderate or more severe hypertension, potentially reducing the subsequent risk of developing cardiovascular disease,” they added.
Study details
Dr McKay and her co-workers recruited 65 adult with pre- and mild hypertension, and aged between 30 and 70, to participate in their randomised, double-blind, placebo-controlled clinical trial.
Subjects were randomly assigned to consume either three servings of brewed hibiscus tea per day or a placebo drink for six weeks. At the end of the study people in the hibiscus tea group displayed an average reduction of 7.2 mmHg in their systolic blood pressure, compared to 1.3 mmHg in the placebo group. A slight but not significant decrease in diastolic blood pressure was also recorded in the hibiscus tea group.
The benefits of hibiscus tea appeared to be greater in people who had higher systolic blood pressure at the start of the study.
Commenting on the potential mechanism, Dr McKay and her co-workers note that previous studies indicated that hibiscus may act by relaxing blood vessels, and this may be linked to calcium channels, or inhibition of the angiotensin converting enzyme (ACE), thereby preventing the conversion of angiotensin I to the potent vasoconstrictor, angiotensin II.
There is also evidence in the scientific literature that hibiscus may act as a diuretic. Another possible explanantion for the apparent benefits is related to the anthocyanin content of H. sabdariffa.
“The specific attributes of H. sabdariffa to cardiovascular health, including its ability to lower BP and its potential hypocholesterolemic effects, are not well understood and further research in this area is warranted,” added the researchers.
Three 240 mL servings a day of tea made with hibiscus (Hibiscus sabdariffa L.) were associated with a 7.2 mmHg reduction in systolic blood pressure and a 3.1 mmHg reduction in diastolic blood pressure, compared to 1.3 and 0.5 mmHg in the placebo group, according to findings published in The Journal of Nutrition.
Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University report that this is the first placebo-controlled clinical trial to study if hibiscus tea, in an amount easily attained from the diet, may affect blood pressure.
“Hypertension is a major risk factor for cardiovascular disease and is associated with substantial morbidity and mortality, estimated to account for 35 per cent of myocardial infarction and stroke, 49 per cent of heart failure, and 24 per cent of premature mortality,” wrote the researchers, led by Dr Diane McKay.
“The dietary change assessed in this study, i.e. regularly incorporating 3 servings/d of hibiscus tea into the diet, effectively reduces blood pressure in pre- and mildly-hypertensive adults.
“This strategy may be useful in preventing the progression to moderate or more severe hypertension, potentially reducing the subsequent risk of developing cardiovascular disease,” they added.
Study details
Dr McKay and her co-workers recruited 65 adult with pre- and mild hypertension, and aged between 30 and 70, to participate in their randomised, double-blind, placebo-controlled clinical trial.
Subjects were randomly assigned to consume either three servings of brewed hibiscus tea per day or a placebo drink for six weeks. At the end of the study people in the hibiscus tea group displayed an average reduction of 7.2 mmHg in their systolic blood pressure, compared to 1.3 mmHg in the placebo group. A slight but not significant decrease in diastolic blood pressure was also recorded in the hibiscus tea group.
The benefits of hibiscus tea appeared to be greater in people who had higher systolic blood pressure at the start of the study.
Commenting on the potential mechanism, Dr McKay and her co-workers note that previous studies indicated that hibiscus may act by relaxing blood vessels, and this may be linked to calcium channels, or inhibition of the angiotensin converting enzyme (ACE), thereby preventing the conversion of angiotensin I to the potent vasoconstrictor, angiotensin II.
There is also evidence in the scientific literature that hibiscus may act as a diuretic. Another possible explanantion for the apparent benefits is related to the anthocyanin content of H. sabdariffa.
“The specific attributes of H. sabdariffa to cardiovascular health, including its ability to lower BP and its potential hypocholesterolemic effects, are not well understood and further research in this area is warranted,” added the researchers.
4 February 2010
A Mind at Rest Strengthens Memories, Researchers Find
ScienceDaily (Jan. 29, 2010) — Our memories are strengthened during periods of rest while we are awake, researchers at New York University have found. The findings, which appear in the latest issue of the journal Neuron, expand our understanding of how memories are boosted -- previous studies had shown this process occurs during sleep, but not during times of awake rest.
"Taking a coffee break after class can actually help you retain that information you just learned," explained Lila Davachi, an assistant professor in NYU's Department of Psychology and Center for Neural Science, in whose laboratory the study was conducted. "Your brain wants you to tune out other tasks so you can tune in to what you just learned."
The study, whose lead author was Arielle Tambini, a doctoral candidate in NYU's Graduate School of Arts and Science, focused on memory consolidation -- the period when a memory is stabilized after it is initially created, or encoded. To determine if memory consolidation occurred during periods of awake rest, the researchers imaged the hippocampus, a brain structure known to play a significant role in memory, and cortical regions during periods of awake rest. Previous studies have demonstrated regions of the brain more active during periods of rest, but their function at these times had been unclear.
The NYU experiment tested subjects' associative memory by showing them pairs of images containing a human face and an object (e.g., a beach ball) or a human face and a scene (e.g., a beach) followed by periods of awake rest. Subjects were not informed their memory for these images would later be tested, but, rather, were instructed to rest and simply think about anything that they wanted, but to remain awake during the resting periods. The researchers used functional magnetic resonance imaging (fMRI) to gauge activity in the hippocampus and cortical regions during the task and during the ensuing rest period.
The experiment yielded two noteworthy results. First, the researchers found that during rest after the study experience (after the visuals were shown), there was a significant correlation between brain activity in the subjects' hippocampus and cortical regions that were active during the initial encoding of each stimulus pair. However, this boost in brain correlations was only seen following experiences that were later memorable suggesting these parts of the brain act in tandem for a purpose -- to consolidate memories during rest. Second, when examining each subject individually, it was found that subjects who had greater resting correlations between the hippocampus and cortex, also exhibited better performance on a subsequent associative memory test and those whose brain correlations were weaker, had worse memory -- in other words, the greater the activity in hippocampus and cortical regions, the stronger the memory.
"Your brain is working for you when you're resting, so rest is important for memory and cognitive function," Davachi observed. "This is something we don't appreciate much, especially when today's information technologies keep us working round-the-clock."
The study's other co-author was Nicholas Ketz, a researcher assistant in the Department of Psychology. The research was supported by a grant from the National Institute of Mental Health and Dart Neuroscience.
"Taking a coffee break after class can actually help you retain that information you just learned," explained Lila Davachi, an assistant professor in NYU's Department of Psychology and Center for Neural Science, in whose laboratory the study was conducted. "Your brain wants you to tune out other tasks so you can tune in to what you just learned."
The study, whose lead author was Arielle Tambini, a doctoral candidate in NYU's Graduate School of Arts and Science, focused on memory consolidation -- the period when a memory is stabilized after it is initially created, or encoded. To determine if memory consolidation occurred during periods of awake rest, the researchers imaged the hippocampus, a brain structure known to play a significant role in memory, and cortical regions during periods of awake rest. Previous studies have demonstrated regions of the brain more active during periods of rest, but their function at these times had been unclear.
The NYU experiment tested subjects' associative memory by showing them pairs of images containing a human face and an object (e.g., a beach ball) or a human face and a scene (e.g., a beach) followed by periods of awake rest. Subjects were not informed their memory for these images would later be tested, but, rather, were instructed to rest and simply think about anything that they wanted, but to remain awake during the resting periods. The researchers used functional magnetic resonance imaging (fMRI) to gauge activity in the hippocampus and cortical regions during the task and during the ensuing rest period.
The experiment yielded two noteworthy results. First, the researchers found that during rest after the study experience (after the visuals were shown), there was a significant correlation between brain activity in the subjects' hippocampus and cortical regions that were active during the initial encoding of each stimulus pair. However, this boost in brain correlations was only seen following experiences that were later memorable suggesting these parts of the brain act in tandem for a purpose -- to consolidate memories during rest. Second, when examining each subject individually, it was found that subjects who had greater resting correlations between the hippocampus and cortex, also exhibited better performance on a subsequent associative memory test and those whose brain correlations were weaker, had worse memory -- in other words, the greater the activity in hippocampus and cortical regions, the stronger the memory.
"Your brain is working for you when you're resting, so rest is important for memory and cognitive function," Davachi observed. "This is something we don't appreciate much, especially when today's information technologies keep us working round-the-clock."
The study's other co-author was Nicholas Ketz, a researcher assistant in the Department of Psychology. The research was supported by a grant from the National Institute of Mental Health and Dart Neuroscience.
Omega-3 may reduce risk of dental disease: Study
Increased levels of omega-3 fatty acid DHA (docosahexaenoic acid) may decrease the risk of dental diseases, suggests a new study from Japan.
The average number of dental disease events was 1.5 times higher in people with low DHA levels, compared to those with the highest average levels of DHA, according to findings published in Nutrition.
In addition to being a major risk factor for tooth loss, periodontal disease has also been implicated as a risk factor for chronic diseases such as cardiovascular disease (CVD). Since the condition may contribute to the overall inflammatory burden of an individual there are reports that this may increase the risk of cardiovascular disease.
The heart health benefits of omega-3 fatty acids are well-documented, being first reported in the early 1970s by Jorn Dyerberg and his co-workers in The Lancet and The American Journal of Clinical Nutrition. To date, the polyunsaturated fatty acids (PUFAs) have been linked to improvements in blood lipid levels, a reduced tendency of thrombosis, blood pressure and heart rate improvements, and improved vascular function.
However, links to dental health are not well documented.
“To our knowledge, this is the first longitudinal study of the relation between periodontal conditions and dietary omega-3 fatty acids intake in older people,” wrote the researchers, led by Masanori Iwasaki from Niigata University.
Study details
The Japanese researchers recruited 55 people with an average age of 74 and calculated dietary intakes of omega-3. The average dietary intakes of EPA and DHA were 947.1 and 635.2 milligrams, respectively, said the researchers.
Over the course of five years, the participants experienced an average of 7.8 periodontal disease events. “People with low DHA intake had an approximately 1.5 times higher incidence rate ratio of periodontal disease progression,” wrote the researchers.
“The findings suggest there may be an inverse, independent relation of dietary DHA intake to the progression of periodontal disease in older people,” they said.
Biologically plausible?
Commenting on the potential mechanism, the researchers note that it is probably related the anti-inflammatory effects of omega-3 fatty acids.
“In periodontal diseases, bacteria trigger inflammatory host responses that cause destruction of the alveolar bone and periodontal connective tissue,” explained the researchers.
“According to previous reports, DHA and EPA inhibit arachidonic acid (AA) metabolism to inflammatory eicosanoids. They also give rise to mediators that are less inflammatory than those produced from AA or that are anti-inflammatory,” they added.
The average number of dental disease events was 1.5 times higher in people with low DHA levels, compared to those with the highest average levels of DHA, according to findings published in Nutrition.
In addition to being a major risk factor for tooth loss, periodontal disease has also been implicated as a risk factor for chronic diseases such as cardiovascular disease (CVD). Since the condition may contribute to the overall inflammatory burden of an individual there are reports that this may increase the risk of cardiovascular disease.
The heart health benefits of omega-3 fatty acids are well-documented, being first reported in the early 1970s by Jorn Dyerberg and his co-workers in The Lancet and The American Journal of Clinical Nutrition. To date, the polyunsaturated fatty acids (PUFAs) have been linked to improvements in blood lipid levels, a reduced tendency of thrombosis, blood pressure and heart rate improvements, and improved vascular function.
However, links to dental health are not well documented.
“To our knowledge, this is the first longitudinal study of the relation between periodontal conditions and dietary omega-3 fatty acids intake in older people,” wrote the researchers, led by Masanori Iwasaki from Niigata University.
Study details
The Japanese researchers recruited 55 people with an average age of 74 and calculated dietary intakes of omega-3. The average dietary intakes of EPA and DHA were 947.1 and 635.2 milligrams, respectively, said the researchers.
Over the course of five years, the participants experienced an average of 7.8 periodontal disease events. “People with low DHA intake had an approximately 1.5 times higher incidence rate ratio of periodontal disease progression,” wrote the researchers.
“The findings suggest there may be an inverse, independent relation of dietary DHA intake to the progression of periodontal disease in older people,” they said.
Biologically plausible?
Commenting on the potential mechanism, the researchers note that it is probably related the anti-inflammatory effects of omega-3 fatty acids.
“In periodontal diseases, bacteria trigger inflammatory host responses that cause destruction of the alveolar bone and periodontal connective tissue,” explained the researchers.
“According to previous reports, DHA and EPA inhibit arachidonic acid (AA) metabolism to inflammatory eicosanoids. They also give rise to mediators that are less inflammatory than those produced from AA or that are anti-inflammatory,” they added.
Don't let your baby swim
NEW YORK (Reuters Health) - Children who start swimming before the age of 2 may be at increased risk of a common infant lung infection, and possibly asthma and respiratory allergies later in life, a new study suggests.
The findings, reported in the European Respiratory Journal, add to evidence that exposure to chlorinated pools may affect children's respiratory health -- particularly if they have a family history of asthma or respiratory allergies like hay fever.
Experts have suspected that the air quality around pools, particularly indoor ones, is to blame. When the chlorine used to disinfect pools combines with swimmers' sweat, saliva or urine, irritating chlorine byproducts are formed, and over time these chemicals may damage the airways.
In the new study, Belgian researchers found that infant swimming -- whether in indoor or outdoor pools -- was linked to a heightened risk of bronchiolitis.
Bronchiolitis is an infection of the lungs' small airways, usually caused by the respiratory syncytial virus, that is common in infants.
In this study, infant swimmers who developed the infection were also at increased risk of developing asthma or respiratory allergies by kindergarten.
"This suggests that chlorinated pool attendance can increase the risk of asthma and respiratory allergies by making the airways more sensitive not only to allergens but also to infectious agents," senior researcher Dr. Alfred Bernard, of Catholic University Louvain in Brussels, told Reuters Health in an email.
He did not advise parents to keep their young children away from pools, since it is an "enjoyable" way for kids to be active.
"Parents should, however, not lose sight that chlorine-based disinfectants and their derivatives are strong irritants not only for the skin but also the airways," Bernard added.
He said that parents should be sure not to over chlorinate their home pools and to try to avoid public pools that are heavily chlorinated. Some clues to the latter, according to Bernard, include an overwhelming chlorine smell, and eye, skin and throat irritation in pool users.
Where possible, the researcher said, parents can also opt for public pools that use alternative disinfecting methods, like ozone treatment -- which has long been used in Europe and is becoming more common in the U.S.
For their study, Bernard and his colleagues assessed 430 Belgian kindergarteners and surveyed parents on their children's health history, swimming habits and other factors.
They found that of children exposed to chlorinated indoor or outdoor pools before age 2, 36 percent had a history of bronchiolitis, compared with 24 percent of their peers.
Among children who had used only indoor pools for more than 20 hours before age 2, the risk of bronchiolitis was 3.5-times higher compared with children who had never been to a chlorinated indoor pool at that age. Meanwhile, children who had spent that much time at an outdoor pool showed a two-fold increase in their risk of the lung infection.
Overall, there were no significant differences in the rates of asthma and allergies among infant swimmers and their peers. But when the researchers looked at children with a history of bronchiolitis, only those who had been infant swimmers showed increased risks of asthma and respiratory allergies.
Among infant swimmers who had contracted the infection, 15 percent later developed asthma. That compared with 4 percent of swimmers with no history of bronchiolitis. The figures were nearly the same when it came to hay fever.
It is "very likely," according to the researchers, that airway irritation from chlorine byproducts makes babies more vulnerable to bronchiolitis.
From there, the infection and chronic chlorine exposure appear to "interact" to increase a child's risk of asthma and allergies later on.
The findings, reported in the European Respiratory Journal, add to evidence that exposure to chlorinated pools may affect children's respiratory health -- particularly if they have a family history of asthma or respiratory allergies like hay fever.
Experts have suspected that the air quality around pools, particularly indoor ones, is to blame. When the chlorine used to disinfect pools combines with swimmers' sweat, saliva or urine, irritating chlorine byproducts are formed, and over time these chemicals may damage the airways.
In the new study, Belgian researchers found that infant swimming -- whether in indoor or outdoor pools -- was linked to a heightened risk of bronchiolitis.
Bronchiolitis is an infection of the lungs' small airways, usually caused by the respiratory syncytial virus, that is common in infants.
In this study, infant swimmers who developed the infection were also at increased risk of developing asthma or respiratory allergies by kindergarten.
"This suggests that chlorinated pool attendance can increase the risk of asthma and respiratory allergies by making the airways more sensitive not only to allergens but also to infectious agents," senior researcher Dr. Alfred Bernard, of Catholic University Louvain in Brussels, told Reuters Health in an email.
He did not advise parents to keep their young children away from pools, since it is an "enjoyable" way for kids to be active.
"Parents should, however, not lose sight that chlorine-based disinfectants and their derivatives are strong irritants not only for the skin but also the airways," Bernard added.
He said that parents should be sure not to over chlorinate their home pools and to try to avoid public pools that are heavily chlorinated. Some clues to the latter, according to Bernard, include an overwhelming chlorine smell, and eye, skin and throat irritation in pool users.
Where possible, the researcher said, parents can also opt for public pools that use alternative disinfecting methods, like ozone treatment -- which has long been used in Europe and is becoming more common in the U.S.
For their study, Bernard and his colleagues assessed 430 Belgian kindergarteners and surveyed parents on their children's health history, swimming habits and other factors.
They found that of children exposed to chlorinated indoor or outdoor pools before age 2, 36 percent had a history of bronchiolitis, compared with 24 percent of their peers.
Among children who had used only indoor pools for more than 20 hours before age 2, the risk of bronchiolitis was 3.5-times higher compared with children who had never been to a chlorinated indoor pool at that age. Meanwhile, children who had spent that much time at an outdoor pool showed a two-fold increase in their risk of the lung infection.
Overall, there were no significant differences in the rates of asthma and allergies among infant swimmers and their peers. But when the researchers looked at children with a history of bronchiolitis, only those who had been infant swimmers showed increased risks of asthma and respiratory allergies.
Among infant swimmers who had contracted the infection, 15 percent later developed asthma. That compared with 4 percent of swimmers with no history of bronchiolitis. The figures were nearly the same when it came to hay fever.
It is "very likely," according to the researchers, that airway irritation from chlorine byproducts makes babies more vulnerable to bronchiolitis.
From there, the infection and chronic chlorine exposure appear to "interact" to increase a child's risk of asthma and allergies later on.
3 February 2010
Health in Your Hands - Your Plan for Natural Scoliosis Prevention and Treatment website is LIVE!
visit it: http://scoliosis.com.sg/index.html
The central premise of my book is how to diagnosis and correct scoliosis non- invasively at any stage in order to arrest it progress before it’s too late.
Scoliosis, is a widespread condition in the world. According to available statistics, the spinal disorder, that leads to an curvature of the spine, strikes nearly two to three percent of all adolescents and becomes noticeable between the age of 10 and 15, when an adolescent is very image conscious.
Nearly, one in 10 Singaporeans suffers from lumbar scoliosis, according to a recent study conducted by a team of spine surgeons led by Professor Wong Hee Kit, chairman of the Orthopedics and Hand & Reconstructive Microsurgery Cluster at the National University Health System (NUHS). Worse, the study also revealed that the condition is 1.6 times more prevalent in women and that it occurs twice more often in Chinese and Malays than in Indians.
Conventional scoliosis treatment involves braces that patients have to wear passively through the day; while surgical procedures carry significant, other risks. My book in contrast draws heavily upon my own experiences as a Chiropractor and Nutritionist, and how I have helped hundreds of scoliosis patients with nothing more elaborate than a highly customized nutritional plan and a structured exercise/stretch program that I’ve explained at length with illustrations in this book.
Among other things, the book explains in simple, layman's language the anatomy and functioning of of the human spine and its relationship to food and exercise. The book is based is painstaking research collected over years of practice with scoliosis patients of all demographics. Testimonials of some of these patients are also appended in the book.
It's my firm conviction that this book will prove a valuable informational resource to the parents, who have children afflicted with scoliosis, as well as adults who suffer from the condition.
2 February 2010
What you eat after exercise matters
BETHESDA, Md. (Jan. 28, 2010) — Many of the health benefits of aerobic exercise are due to the most recent exercise session (rather than weeks, months and even years of exercise training), and the nature of these benefits can be greatly affected by the food we eat afterwards, according to a study published in the Journal of Applied Physiology (http://jap.physiology.org).
"Differences in what you eat after exercise produce different effects on the body's metabolism," said the study's senior author, Jeffrey F. Horowitz of the University of Michigan. This study follows up on several previous studies that demonstrate that many health benefits of exercise are transient: one exercise session produces benefits to the body that taper off, generally within hours or a few days.
"Many of the improvements in metabolic health associated with exercise stem largely from the most recent session of exercise, rather than from an increase in 'fitness' per se," Dr. Horowitz said. "But exercise doesn't occur in a vacuum, and it is very important to look at both the effects of exercise and what you're eating after exercise."
Specifically, the study found that exercise enhanced insulin sensitivity, particularly when meals eaten after the exercise session contained relatively low carbohydrate content. Enhanced insulin sensitivity means that it is easier for the body to take up sugar from the blood stream into tissues like muscles, where it can be stored or used as fuel. Impaired insulin sensitivity (i.e., "insulin resistance") is a hallmark of Type II diabetes, as well as being a major risk factor for other chronic diseases, such as heart disease.
Interestingly, when the research subjects in this study ate relatively low-calorie meals after exercise, this did not improve insulin sensitivity any more than when they ate enough calories to match what they expended during exercise. This suggests that you don't have to starve yourself after exercise to still reap some of the important health benefits.
The paper, "Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity," appears in the online edition of the journal. The authors are Sean A. Newsom, Simon Schenk, Kristin M. Thomas, Matthew P. Harber, Nicolas D. Knuth, Haila Goldenberg and Dr. Horowitz. All are at the University of Michigan. The American Physiological Society (APS: www.the-aps.org) published the research.
Study Design
The study included nine healthy sedentary men, all around 28-30 years old. They spent four separate sessions in the Michigan Clinical Research Unit in the University of Michigan Hospital. Each session lasted for approximately 29 hours. They fasted overnight before attending each session, which began in the morning.
The four hospital visits differed primarily by the meals eaten after exercise. The following describes the four different visits:
They did not exercise and ate meals to match their daily calorie expenditure. This was the control trial.
They exercised for approximately 90 min at moderate intensity, and then ate meals that matched their caloric expenditure. The carbohydrate, fat, and protein content of these meals were also appropriately balanced to match their expenditure.
They exercised for approximately 90 min at moderate intensity and then ate meals with relatively low carbohydrate content, but they ate enough total calories to match their calorie expenditure. This reduced-carbohydrate meal contained about 200 grams of carbohydrate, less than half the carbohydrate content of the balanced meal.
They exercised for approximately 90 min at moderate intensity and then ate relatively low-calorie meals, that is, meals that provided less energy than was expended (about one-third fewer calories than the meals in the other two exercise trials). These meals contained a relatively high carbohydrate content to replace the carbohydrate "burned" during exercise.
The exercise was performed on a stationary bicycle and a treadmill. The order in which the participants did the trials was randomized.
In the three exercise trials, there was a trend for an increase in insulin sensitivity. However, when participants ate less carbohydrate after exercise, this enhanced insulin sensitivity significantly more. Although weight loss is important for improving metabolic health in overweight and obese people, these results suggests that people can still reap some important health benefits from exercise without undereating or losing weight, Dr. Horowitz said.
The study also reinforces the growing body of evidence that each exercise session can affect the body's physiology and also that differences in what you eat after exercise can produce different physiological changes.
Next Steps
The research team is now performing experiments with obese people, aimed at better identifying the minimum amount of exercise that will still improve insulin sensitivity at least into the next day.
"Differences in what you eat after exercise produce different effects on the body's metabolism," said the study's senior author, Jeffrey F. Horowitz of the University of Michigan. This study follows up on several previous studies that demonstrate that many health benefits of exercise are transient: one exercise session produces benefits to the body that taper off, generally within hours or a few days.
"Many of the improvements in metabolic health associated with exercise stem largely from the most recent session of exercise, rather than from an increase in 'fitness' per se," Dr. Horowitz said. "But exercise doesn't occur in a vacuum, and it is very important to look at both the effects of exercise and what you're eating after exercise."
Specifically, the study found that exercise enhanced insulin sensitivity, particularly when meals eaten after the exercise session contained relatively low carbohydrate content. Enhanced insulin sensitivity means that it is easier for the body to take up sugar from the blood stream into tissues like muscles, where it can be stored or used as fuel. Impaired insulin sensitivity (i.e., "insulin resistance") is a hallmark of Type II diabetes, as well as being a major risk factor for other chronic diseases, such as heart disease.
Interestingly, when the research subjects in this study ate relatively low-calorie meals after exercise, this did not improve insulin sensitivity any more than when they ate enough calories to match what they expended during exercise. This suggests that you don't have to starve yourself after exercise to still reap some of the important health benefits.
The paper, "Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity," appears in the online edition of the journal. The authors are Sean A. Newsom, Simon Schenk, Kristin M. Thomas, Matthew P. Harber, Nicolas D. Knuth, Haila Goldenberg and Dr. Horowitz. All are at the University of Michigan. The American Physiological Society (APS: www.the-aps.org) published the research.
Study Design
The study included nine healthy sedentary men, all around 28-30 years old. They spent four separate sessions in the Michigan Clinical Research Unit in the University of Michigan Hospital. Each session lasted for approximately 29 hours. They fasted overnight before attending each session, which began in the morning.
The four hospital visits differed primarily by the meals eaten after exercise. The following describes the four different visits:
They did not exercise and ate meals to match their daily calorie expenditure. This was the control trial.
They exercised for approximately 90 min at moderate intensity, and then ate meals that matched their caloric expenditure. The carbohydrate, fat, and protein content of these meals were also appropriately balanced to match their expenditure.
They exercised for approximately 90 min at moderate intensity and then ate meals with relatively low carbohydrate content, but they ate enough total calories to match their calorie expenditure. This reduced-carbohydrate meal contained about 200 grams of carbohydrate, less than half the carbohydrate content of the balanced meal.
They exercised for approximately 90 min at moderate intensity and then ate relatively low-calorie meals, that is, meals that provided less energy than was expended (about one-third fewer calories than the meals in the other two exercise trials). These meals contained a relatively high carbohydrate content to replace the carbohydrate "burned" during exercise.
The exercise was performed on a stationary bicycle and a treadmill. The order in which the participants did the trials was randomized.
In the three exercise trials, there was a trend for an increase in insulin sensitivity. However, when participants ate less carbohydrate after exercise, this enhanced insulin sensitivity significantly more. Although weight loss is important for improving metabolic health in overweight and obese people, these results suggests that people can still reap some important health benefits from exercise without undereating or losing weight, Dr. Horowitz said.
The study also reinforces the growing body of evidence that each exercise session can affect the body's physiology and also that differences in what you eat after exercise can produce different physiological changes.
Next Steps
The research team is now performing experiments with obese people, aimed at better identifying the minimum amount of exercise that will still improve insulin sensitivity at least into the next day.
1 February 2010
Another blood pressure concern: Link to dementia
WASHINGTON (AP) — If the cardiologist's warnings don't scare you, consider this: Controlling blood pressure just might be the best protection yet known against dementia.
In a flurry of new research, scientists scanned people's brains to show hypertension fuels a kind of scarring linked to later development of Alzheimer's disease and other dementias. Those scars can start building up in middle age, decades before memory problems will appear.
BLOOD PRESSURE: Lower among parents -- really
ALZHEIMER'S: Video, latest news, what you need to know
BLOG: Bob Blackwell on Living with Alzheimer's, warning signs
The evidence is strong enough that the National Institutes of Health soon will begin enrolling thousands of hypertension sufferers in a major study to see if aggressive treatment — pushing blood pressure lower than currently recommended — better protects not just their hearts but their brains.
"If you look ... for things that we can prevent that lead to cognitive decline in the elderly, hypertension is at the top of the list," Dr. Walter Koroshetz, deputy director of NIH's National Institute of Neurological Disorders and Stroke, told The Associated Press.
Age is the biggest risk factor for Alzheimer's disease and other forms of dementia that affect about one in eight people 65 or older.
Scientists have long noticed that some of the same triggers for heart disease — high blood pressure, obesity, diabetes — seem to increase the risk of dementia, too. But for years, they thought that link was with "vascular dementia," memory problems usually linked to small strokes, and not the scarier classic Alzheimer's disease.
Now those lines are blurring as specialists realize that many if not most patients have a mix of the two dementias. Somehow, factors like hypertension — blood pressure readings of 140 over 90 or higher — that weaken arteries also seem to spur Alzheimer's disease-like processes.
One suspect: Scarring known as white matter lesions. White matter acts as the brain's telephone network, a system of axons, or nerve fibers, that allow brain cells to communicate with each other. Even slightly elevated blood pressure can damage the tiny blood vessels that nourish white matter, interrupting those signals.
Among the strongest new studies:
•MRI scans showed women 65 and older with high blood pressure had significantly more white matter lesions in their brains eight years later. The study included 1,403 women who were enrolled in a memory subset of the landmark Women's Health Initiative that tracked postmenopausal health. The worse their blood pressure, the higher volume of white matter damage, says the study published online last month in the Journal of Clinical Hypertension.
"This is a silent disease in the brain," says lead researcher Dr. Lewis Kuller of the University of Pittsburgh. "It's evolving over time and it leads to very bad outcomes."
•The journal Stroke just published similar evidence from a Johns Hopkins University-led study that tracked 983 people for more than 15 years, starting in middle age. The longer people spent with uncontrolled high blood pressure, the more white matter damage they accumulated. The researchers could see a change with each 20-point jump in too-high systolic pressure, the top number in a blood-pressure reading.
Clearly, hypertension alone doesn't doom someone to later dementia. Far more people, nearly one in three U.S. adults, have hypertension.
And there are plenty of other reasons to lower blood pressure: Hypertension is a leading cause of heart attacks, strokes and kidney failure.
But while some studies have found hypertension treatment lowered the dementia risk, others haven't.
Enter the NIH's SPRINT study, which in a few months is to begin enrolling 7,500 hypertension patients age 55 and older around the country. The test: Whether aggressive treatment to lower systolic blood pressure below 120 — what's considered normal — will prove healthier than today's guidelines that urge getting it below 140, or 130 for diabetics.
The main focus is on heart and kidney health. But all participants will be screened for dementia, and a subset will undergo repeated cognitive testing and MRI scans to tell if lowering blood pressure also protects against a slide toward dementia. Another question: If older patients can tolerate bigger than usual blood pressure drops without side effects, such as falls.
With dementia rising fast as the population grays, even a small effect from better blood pressure control could have a big public health impact, says Dr. William Thies of the Alzheimer's Association.
Other dementia-preventing efforts, such as targeting the sticky amyloid plaques in Alzheimer's patients brains, haven't panned out so far — while hypertension control has little downside, notes Pittsburgh's Kuller.
"Until I can tell you how to get rid of amyloid in your brain, take care of the blood pressure."
In a flurry of new research, scientists scanned people's brains to show hypertension fuels a kind of scarring linked to later development of Alzheimer's disease and other dementias. Those scars can start building up in middle age, decades before memory problems will appear.
BLOOD PRESSURE: Lower among parents -- really
ALZHEIMER'S: Video, latest news, what you need to know
BLOG: Bob Blackwell on Living with Alzheimer's, warning signs
The evidence is strong enough that the National Institutes of Health soon will begin enrolling thousands of hypertension sufferers in a major study to see if aggressive treatment — pushing blood pressure lower than currently recommended — better protects not just their hearts but their brains.
"If you look ... for things that we can prevent that lead to cognitive decline in the elderly, hypertension is at the top of the list," Dr. Walter Koroshetz, deputy director of NIH's National Institute of Neurological Disorders and Stroke, told The Associated Press.
Age is the biggest risk factor for Alzheimer's disease and other forms of dementia that affect about one in eight people 65 or older.
Scientists have long noticed that some of the same triggers for heart disease — high blood pressure, obesity, diabetes — seem to increase the risk of dementia, too. But for years, they thought that link was with "vascular dementia," memory problems usually linked to small strokes, and not the scarier classic Alzheimer's disease.
Now those lines are blurring as specialists realize that many if not most patients have a mix of the two dementias. Somehow, factors like hypertension — blood pressure readings of 140 over 90 or higher — that weaken arteries also seem to spur Alzheimer's disease-like processes.
One suspect: Scarring known as white matter lesions. White matter acts as the brain's telephone network, a system of axons, or nerve fibers, that allow brain cells to communicate with each other. Even slightly elevated blood pressure can damage the tiny blood vessels that nourish white matter, interrupting those signals.
Among the strongest new studies:
•MRI scans showed women 65 and older with high blood pressure had significantly more white matter lesions in their brains eight years later. The study included 1,403 women who were enrolled in a memory subset of the landmark Women's Health Initiative that tracked postmenopausal health. The worse their blood pressure, the higher volume of white matter damage, says the study published online last month in the Journal of Clinical Hypertension.
"This is a silent disease in the brain," says lead researcher Dr. Lewis Kuller of the University of Pittsburgh. "It's evolving over time and it leads to very bad outcomes."
•The journal Stroke just published similar evidence from a Johns Hopkins University-led study that tracked 983 people for more than 15 years, starting in middle age. The longer people spent with uncontrolled high blood pressure, the more white matter damage they accumulated. The researchers could see a change with each 20-point jump in too-high systolic pressure, the top number in a blood-pressure reading.
Clearly, hypertension alone doesn't doom someone to later dementia. Far more people, nearly one in three U.S. adults, have hypertension.
And there are plenty of other reasons to lower blood pressure: Hypertension is a leading cause of heart attacks, strokes and kidney failure.
But while some studies have found hypertension treatment lowered the dementia risk, others haven't.
Enter the NIH's SPRINT study, which in a few months is to begin enrolling 7,500 hypertension patients age 55 and older around the country. The test: Whether aggressive treatment to lower systolic blood pressure below 120 — what's considered normal — will prove healthier than today's guidelines that urge getting it below 140, or 130 for diabetics.
The main focus is on heart and kidney health. But all participants will be screened for dementia, and a subset will undergo repeated cognitive testing and MRI scans to tell if lowering blood pressure also protects against a slide toward dementia. Another question: If older patients can tolerate bigger than usual blood pressure drops without side effects, such as falls.
With dementia rising fast as the population grays, even a small effect from better blood pressure control could have a big public health impact, says Dr. William Thies of the Alzheimer's Association.
Other dementia-preventing efforts, such as targeting the sticky amyloid plaques in Alzheimer's patients brains, haven't panned out so far — while hypertension control has little downside, notes Pittsburgh's Kuller.
"Until I can tell you how to get rid of amyloid in your brain, take care of the blood pressure."
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