Cholesterol

A study involving 74 older adults (70+), of whom 3 had mild dementia, 33 were cognitively normal and 38 had mild cognitive impairment, has found that high levels of "good" cholesterol and low levels of "bad" cholesterol correlated with lower levels of the amyloid-beta plaques in the brain (a hallmark of Alzheimer's disease).

http://www.eurekalert.org/pub_releases/2013-12/uoc--hga122613.php

The new label of ‘metabolic syndrome’ applies to those having three or more of the following risk factors: high blood pressure, excess belly fat, higher than normal triglycerides, high blood sugar and low high-density lipoprotein (HDL) cholesterol (the "good" cholesterol). Metabolic syndrome has been linked to increased risk of heart attack.

A new French study, involving over 7,000 older adults (65+) has found that those with metabolic syndrome were 20% more likely to show cognitive decline on a memory test (MMSE) over a two or four year interval. They were also 13% more likely to show cognitive decline on a visual working memory test. Specifically, higher triglycerides and low HDL cholesterol were linked to poorer memory scores; diabetes (but not higher fasting blood sugar) was linked to poorer visual working memory and word fluency scores.

The findings point to the importance of managing the symptoms of metabolic syndrome.

High cholesterol and blood pressure in middle age tied to early memory problems

Another study, involving some 4800 middle-aged adults (average age 55), has found that those with higher cardiovascular risk were more likely to have lower cognitive function and a faster rate of cognitive decline over a 10-year period. A 10% higher cardiovascular risk was associated not only with increased rate of overall mental decline, but also poorer cognitive test scores in all areas except reasoning for men and fluency for women.

The cardiovascular risk score is based on age, sex, HDL cholesterol, total cholesterol, systolic blood pressure and whether participants smoked or had diabetes.

Memory problems may be sign of stroke risk

A very large study (part of the REGARDS study) tested people age 45 and older (average age 67) who had never had a stroke. Some 14,842 people took a verbal fluency test, and 17,851 people took a word recall memory test. In the next 4.5 years, 123 participants who had taken the verbal fluency test and 129 participants who had taken the memory test experienced a stroke.

Those who had scored in the bottom 20% for verbal fluency were 3.6 times more likely to develop a stroke than those who scored in the top 20%. For the memory test, those who scored in the bottom 20% were 3.5 times more likely to have a stroke than those in the top quintile.

The effect was greatest at the younger ages. At age 50, those who scored in the bottom quintile of the memory test were 9.4 times more likely to later have a stroke than those in the top quintile.

 

Together, these studies, which are consistent with many previous studies, confirm that cardiovascular problems and diabetes add to the risk of greater cognitive decline (and possible dementia) in old age. And point to the importance of treating these problems as soon as they appear.

[2147] Raffaitin C, Féart C, Le Goff M, Amieva H, Helmer C, Akbaraly TN, Tzourio C, Gin H, Barberger-Gateau P. Metabolic syndrome and cognitive decline in French elders. Neurology [Internet]. 2011 ;76(6):518 - 525. Available from: http://www.neurology.org/content/76/6/518.abstract

The findings of the second and third studies are to be presented at the American Academy of Neurology's 63rd Annual Meeting in Honolulu April 9 to April 16, 2011

Research into the link, if any, between cholesterol and dementia, has been somewhat contradictory. A very long-running Swedish study may explain why. The study, involving 1,462 women aged 38-60 in 1968, has found that cholesterol measured in middle or old age showed no link to dementia, but there was a connection between dementia and the rate of decline in cholesterol level. Those women whose cholesterol levels decreased the most from middle to older age were more than twice as likely to develop dementia as those whose cholesterol levels increased or stayed the same (17.5% compared to 8.9%).After 32 years, 161 women had developed dementia.

Later in life, women with slightly higher body mass index, higher levels of cholesterol and higher blood pressure tend to be healthier overall than those whose weight, cholesterol and blood pressure are too low. But it is unclear whether "too low" cholesterol, BMI and blood pressure are risk factors for dementia or simply signs that dementia is developing, for reasons we do not yet understand.

On the other hand, a recent rat study has found that consuming a high cholesterol diet for five months caused memory impairment, cholinergic dysfunction, inflammation, enhanced cortical beta-amyloid and tau and induced microbleedings — all of which is strikingly similar to Alzheimer's pathology. And this finding is consistent with a number of other studies. So it does seem clear that the story of how exactly cholesterol impacts Alzheimer’s is a complex one that we are just beginning to unravel.

In light of other research indicating that the response of men and women to various substances (eg caffeine) may be different, we should also bear in mind that the results of the Swedish study may apply only to women.

A theory that changes in fat metabolism in the membranes of nerve cells play a role in Alzheimer's has been supported in a recent study. The study found significantly higher levels of ceramide and cholesterol in the middle frontal gyrus of Alzheimer's patients. The researchers suggest that alterations in fats (especially cholesterol and ceramide) may contribute to a "neurodegenerative cascade" that destroys neurons in Alzheimer's, and that the accumulation of ceramide and cholesterol is triggered by the oxidative stress brought on by the presence of the toxic beta amyloid peptide. The study also suggests a reason for why antioxidants such as vitamin E might delay the onset of Alzheimer's: treatment with Vitamin E reduced the levels of ceramide and cholesterol, resulting in "a significant decrease in the number of neurons killed by the beta amyloid and oxidative stress.

Cutler, R.G., Kelly, J., Storie, K., Pedersen, W.A., Tammara, A., Hatanpaa, K., Troncoso, J.C. & Mattson, M.P. 2004. Involvement of oxidative stress-induced abnormalities in ceramide and cholesterol metabolism in brain aging and Alzheimer's disease. PNAS, 101, 2070-5.

Older news items (pre-2010) brought over from the old website

Fat around the middle increases the risk of dementia

Data from the Prospective Population Study of Women in Gothenburg, involving a representative sample of 1,462 nondemented women followed from 1968 at ages 38-60 years, and followed-up in 1974, 1980, 1992, and 2000, has revealed that women who were broader around the waist than the hips in middle age ran slightly more than twice the risk of developing dementia when they got old. However, unlike other studies, no link was found to a high BMI. It should be noted, though, that obesity and overweight were relatively unusual among the participants of this study.

Gustafson, D. R., Backman, K., Waern, M., Ostling, S., Guo, X., Zandi, P., et al. (2009). Adiposity indicators and dementia over 32 years in Sweden. Neurology, 73(19), 1559-1566.

http://www.eurekalert.org/pub_releases/2009-11/uog-fat112309.php

Fast food a potential risk factor for Alzheimer's

Genetically engineered mice fed a diet rich in fat, sugar and cholesterol for nine months developed a preliminary stage of the morbid irregularities that form in the brains of Alzheimer's patients. The findings suggest that a ‘fast food’ diet could be a contributory factor in those with the Alzheimer’s gene.

Akterin, S. 2008. From cholesterol to oxidative stress in Alzheimer's disease: A wide perspective on a multifactorial disease. Doctoral thesis, Karolinska Institutet.
Thesis available at: http://diss.kib.ki.se/2008/978-91-7409-172-4/

http://www.eurekalert.org/pub_releases/2008-11/ki-ffa112808.php

Low levels of good cholesterol linked to memory loss, dementia risk

Previous research has focused on total or LDL cholesterol levels because they are proven risk factors for cardiovascular disease, but data from the Whitehall II study has found that low levels of high-density lipoproteins (HDL) — the "good" cholesterol — in middle age were associated with a significantly greater risk of memory loss by age 60. Total cholesterol and triglycerides did not show a link with memory decline. To raise HDL and lower LDL cholesterol, the American Heart Association recommends exercising regularly; eliminating trans fats from the diet; reducing the intake of all fats, especially saturated fats; and consuming monounsaturated fats, such as olive, canola and peanut oils. (for more advice on cholesterol see www.americanheart.org/cholesterol)

[1144] Singh-Manoux A, Gimeno D, Kivimaki M, Brunner E, Marmot MG. Low HDL cholesterol is a risk factor for deficit and decline in memory in midlife: the Whitehall II study. Arteriosclerosis, Thrombosis, and Vascular Biology [Internet]. 2008 ;28(8):1556 - 1562. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18591462

http://www.eurekalert.org/pub_releases/2008-06/aha-llo062708.php

High cholesterol in your 40s increases risk of Alzheimer's disease

A study involving nearly 10,000 people who underwent health evaluations between 1964 and 1973 when they were between the ages of 40 and 45, has found that those with total cholesterol levels between 249 and 500 milligrams were one-and-a-half times more likely to develop Alzheimer's disease than those people with cholesterol levels of less than 198 milligrams. People with total cholesterol levels of 221 to 248 milligrams were more than one-and-a-quarter times more likely to develop Alzheimer's disease. High cholesterol increased risk regardless of midlife diabetes, high blood pressure, obesity, smoking and late-life stroke.

The research was presented at the American Academy of Neurology Annual Meeting in Chicago, April 12 – April 19.

http://www.eurekalert.org/pub_releases/2008-04/aaon-hci040208.php

Obesity significantly increases dementia risk

A review of 10 international studies published since 1995, covering just over 37,000 people, has found that obesity increased the relative risk of dementia by an average of 42% compared with normal weight. Being underweight increased the risk by 36%. For Alzheimer's Disease and vascular dementia, specifically, obesity was an even more significant risk: 80% and 73%, respectively. With regards to Alzheimer’s, obesity was more likely to be a risk factor for women, but men were more affected when it came to vascular dementia.

Beydoun, M.A., Beydoun, H.A. & Wang, Y. 2008. Obesity and central obesity as risk factors for incident dementia and its subtypes: a systematic review and meta-analysis. Obesity Reviews, 9 (3), 204–218.

http://www.physorg.com/news129376360.html

Larger belly in mid-life increases risk of dementia

A study involving 6,583 people measured abdominal fat at age 40 to 45, and dementia occurrence some 36 years later. Those with the highest amount of abdominal fat were found to be nearly three times more likely to develop dementia than those with the lowest amount of abdominal fat. Having a large abdomen increased the risk of dementia regardless of overall weight and existing health conditions, although being obese as well did increase the risk. Those more likely to have abdominal obesity, were women, non-whites, smokers, people with high blood pressure, high cholesterol or diabetes, and those with less than a high school level of education.

Whitmer, R.A., et al. 2008. Central obesity and increased risk of dementia more than three decades later. Neurology, published online ahead of print March 26

http://www.eurekalert.org/pub_releases/2008-03/aaon-lbi031808.php

Not enough 'good' cholesterol makes it harder to recover from stroke

A large study involving men and women over age 35 in the United States, Canada, and Scotland who had suffered a mild to moderate stroke within the past three months, found several factors predicted memory and disability problems after stroke: increased age, non-Caucasian race, recurrent stroke, diabetes, stroke in the left hemisphere of the brain, higher levels of homocysteine and lower levels of high-density lipoproteins (HDL), otherwise known as “good” cholesterol. “People with low levels of HDL, high levels of homocysteine, and diabetes are twice as likely as those without such problems to have poorer cognitive function and greater disability after stroke … (and) stroke recovery was the most difficult for people over the age of 57 with high levels of homocysteine ...”

[735] Newman GC, Bang H, Hussain SI, Toole JF. Association of diabetes, homocysteine, and HDL with cognition and disability after stroke. Neurology [Internet]. 2007 ;69(22):2054 - 2062. Available from: http://www.neurology.org/cgi/content/abstract/69/22/2054

http://www.eurekalert.org/pub_releases/2007-11/aaon-ne112007.php

Alzheimer’s most often found in combination with other disease

Post-mortem data from a large, long-running study has found that only 30% of people with signs of dementia had Alzheimer’s disease alone. 42% had Alzheimer’s disease with cerebral infarcts (strokes) and 16% had Alzheimer’s disease with Parkinson’s disease (including two people with all three conditions). Infarcts alone caused another 12% of the cases. Vascular dementia caused another 12%. In those without dementia, brain autopsy revealed the presence of Alzheimer’s in 24% of cases, and infarctions in 18%. The finding that Alzheimer’s pathology with cerebral infarcts is a very common combination in people with dementia adds to emerging evidence that dementia risk might be reduced with the same tools we use for cardiovascular disease such as control of blood cholesterol levels and hypertension.

Schneider, J.A., Arvanitakis, Z., Bang, W. & Bennett, D.A. 2007. Mixed brain pathologies account for most dementia cases in community-dwelling older persons. Neurology, published ahead of print June 13

http://www.eurekalert.org/pub_releases/2007-06/nioa-sfm061207.php

More on why high cholesterol might increase your risk of Alzheimer’s

A cell study provides more understanding of why there might be a link between cholesterol and Alzheimer's disease. The study found that proteins which help control cholesterol levels in arterial walls were also present in neurons, and when the genes for these proteins were over-expressed, production of amyloid beta protein fell. The finding suggests a new approach to slowing Alzheimer’s. The study also showed that the apoE protein is extremely good at regulating cholesterol removal from neurons — the gene for this protein is a well-known genetic risk factor for Alzheimer's.

The study appeared in the February issue of the Journal of Biological Chemistry.

http://www.newscientist.com/article/mg19325905.200?DCMP=NLC-nletter&nsref=mg19325905.200

Predicting dementia risk

A large Scandinavian study has succeeded in calculating middle-aged people's chances of developing dementia later in life with 70% accuracy. The study confirms the importance of lifestyle factors. The study assessed factors such as blood pressure, body fat and cholesterol levels in 1,400 middle-aged Finns in the 1970s and 1980s, and found that those who at 40 were obese, or had high blood pressure, or high cholesterol levels, were twice as more likely to develop dementia by the age of 60. Having all three of these risk factors increased their chances six-fold. Other risk factors were age and low education.

[2404] Kivipelto M, Ngandu T, Laatikainen T, Winblad B, Soininen H, Tuomilehto J. Risk score for the prediction of dementia risk in 20 years among middle aged people: a longitudinal, population-based study. The Lancet Neurology [Internet]. 2006 ;5(9):735 - 741. Available from: http://www.thelancet.com/journals/laneur/article/PIIS1474-4422(06)70537-3/abstract

http://society.guardian.co.uk/health/story/0,,1836464,00.html

Low cholesterol also associated with impaired cognition

Data from 789 men and 1,105 women from the Framingham Heart Study has found that those who had the lowest total cholesterol performed significantly more poorly on tests of similarities, word fluency, and attention/concentration than patients with higher cholesterol levels. Those in the lowest total cholesterol group (a level of under 200) were 49% more likely to perform poorly and 80% more likely to perform very poorly than were participants in the highest total cholesterol group (240 to 380). The finding should not be taken as a warning against those with high cholesterol taking medication to lower it; the study applies to those with naturally low cholesterol levels, and previous studies have shown that both high and low cholesterol have led to poor cognitive performance.

[1242] Elias PK, Elias MF, D'Agostino RB, Sullivan LM, Wolf PA. Serum cholesterol and cognitive performance in the Framingham Heart Study. Psychosomatic Medicine [Internet]. 2005 ;67(1):24 - 30. Available from: http://www.ncbi.nlm.nih.gov/pubmed/15673620

http://preventdisease.com/news/articles/021505_low_cholesterol_mental.shtml

Loss of body mass linked to development of Alzheimer's disease

People with Alzheimer's disease are known to lose weight and body mass after they have the disease, but now the Religious Orders Study has revealed that loss in body mass index is associated with a greater risk of developing the disease. People who lost approximately one unit of BMI per year had a 35% greater risk than people with no change in BMI; those with no change in BMI had a 20% greater risk of developing the disease than that of people who gained six-tenths of a unit of BMI per year. A similar relationship was also found between changes in BMI and rate of cognitive decline. The findings are supported by recently published findings of the Honolulu-Asia Aging Study, showing that dementia-associated weight loss in Japanese-American men begins before the onset of dementia and accelerates by the time of diagnosis.

Buchman, A.S., Wilson, R.S., Bienias, J.L., Shah, R.C., Evans, D.A. & Bennett, D.A. 2005. Change in body mass index and risk of incident Alzheimer disease. Neurology, 65, 892-897.

http://www.eurekalert.org/pub_releases/2005-09/nioa-lob092105.php

More support that high cholesterol is a risk factor for cognitive impairment

A new study has found that patients with a history of high cholesterol had a lower risk of cognitive impairment three to six months after stroke. The finding likely relates to high cholesterol treatment, rather than any positive effect of cholesterol. About 45% of the patients were being treated with cholesterol-lowering drugs known as statins before their stroke. Previous observational studies have indicated that statin therapy is associated with a reduced risk of Alzheimer's disease and vascular dementia.
A study of 103 consecutive ischemic stroke patients — 41 diagnosed with VCIND (vascular cognitive impairment-no dementia) and 62 who had no evidence of cognitive impairment after their strokes — identified three statistically significant predictors of cognitive impairment: the patient's level of education, the presence of heart disease, and a history of high cholesterol (hypercholesterolemia). When the researchers controlled for education level (education being an established protective factor for cognitive impairment), only hypercholesterolemia remained as a statistically significant predictor of the risk for cognitive impairment.

The studies were presented at the American Stroke Association's 29th International Stroke Conference.

http://www.eurekalert.org/pub_releases/2004-02/aha-cdm012704.php

Alzheimer's, cardiovascular disease share risk factors

A study of 4,081 women aged 65 years and older has investigated the relationship between cardiovascular risk factors and cognitive function. The researchers found a consistent increase in cognitive health paralleling higher levels of HDL (“good” cholesterol). A less robust correlation was seen for lower levels of LDL (or "bad") cholesterol and better cognitive performance. Triglyceride levels did not appear to influence cognition.

A study of over 700 elderly men and women has investigated the relationship between diabetes and cardiovascular disease risk factors and cognitive health. Researchers found that the presence of coronary heart disease, high cholesterol, or hypertension increased the risk of later cognitive decline, with a particularly strong effect in African Americans. They also found that although the diagnosis of diabetes increased the risk of cognitive decline by as much as two fold, the presence of high levels of fasting glucose (therefore, low insulin levels) substantially decreased the risk of cognitive decline in diabetic patients.

Reported at The 9th International Conference on Alzheimer's Disease and Related Disorders (ICAD), July 17-22, at the Pennsylvania Convention Center in Philadelphia, Pennsylvania:

Elizabeth Devore – Plasma Cholesterol Levels and Cognitive Function in Aging Women (O3-01-02, Tues., 7/20, 3-5 pm)

Jacobo Mintzer – Effects of Diabetes Mellitus and Other Elderly CVD Risk Factors on Change in cognitive Function Later in Life (P4-015, Wed., 7/21, 12:30)

http://www.eurekalert.org/pub_releases/2004-07/aa-acd070804.php

Why diet, hormones, exercise might delay Alzheimer’s

A theory that changes in fat metabolism in the membranes of nerve cells play a role in Alzheimer's has been supported in a recent study. The study found significantly higher levels of ceramide and cholesterol in the middle frontal gyrus of Alzheimer's patients. The researchers suggest that alterations in fats (especially cholesterol and ceramide) may contribute to a "neurodegenerative cascade" that destroys neurons in Alzheimer's, and that the accumulation of ceramide and cholesterol is triggered by the oxidative stress brought on by the presence of the toxic beta amyloid peptide. The study also suggests a reason for why antioxidants such as vitamin E might delay the onset of Alzheimer's: treatment with Vitamin E reduced the levels of ceramide and cholesterol, resulting in "a significant decrease in the number of neurons killed by the beta amyloid and oxidative stress.

[2398] Cutler RG, Kelly J, Storie K, Pedersen WA, Tammara A, Hatanpaa K, Troncoso JC, Mattson MP. Involvement of oxidative stress-induced abnormalities in ceramide and cholesterol metabolism in brain aging and Alzheimer's disease. Proceedings of the National Academy of Sciences of the United States of America [Internet]. 2004 ;101(7):2070 - 2075. Available from: http://www.pnas.org/content/101/7/2070.abstract

http://www.eurekalert.org/pub_releases/2004-02/aaft-nsm021004.php

High cholesterol risk factor for the development of Alzheimer-related amyloid deposits

A review of autopsy cases of patients over 40 years old found that high blood cholesterol levels were correlated with the presence of amyloid deposits in the brain in the youngest subjects (aged 40-55).

[2407] Pappolla MA, Bryant-Thomas TK, Herbert D, Pacheco J, Fabra Garcia M, Manjon M, Girones X, Henry TL, Matsubara E, Zambon D, et al. Mild hypercholesterolemia is an early risk factor for the development of Alzheimer amyloid pathology. Neurology [Internet]. 2003 ;61(2):199 - 205. Available from: http://www.neurology.org/content/61/2/199.abstract

Cholesterol not a risk factor for Alzheimer's

Previously, the long-running, large-scale Framingham study found people with elevated levels of homocysteine in the blood had nearly double the risk of developing Alzheimer’s disease (AD). The study now clarifies the inconclusive results from previous studies regarding whether plasma cholesterol levels are associated with increased risk ofAlzheimer disease (AD). They found that, after adjustment for age, sex, APOE genotype,smoking, body mass index, coronary heart disease,and diabetes, there was no significant association between ADrisk and cholesterol level.

[439] Tan ZS, Seshadri S, Beiser A, Wilson PWF, Kiel DP, Tocco M, D'Agostino RB, Wolf PA. Plasma Total Cholesterol Level as a Risk Factor for Alzheimer Disease: The Framingham Study. Arch Intern Med [Internet]. 2003 ;163(9):1053 - 1057. Available from: http://archinte.ama-assn.org/cgi/content/abstract/163/9/1053

http://archinte.ama-assn.org/cgi/content/abstract/163/9/1053

New study counters previous research linking intake of dietary fat with increased risk of dementia

Previous studies suggesting that fat may be involved in the development of dementia and Alzheimer’s disease have been contradicted by a new study involving over 5,000 elderly people over a period of six years. The study found no correlation between fat and cholesterol intake and risk of dementia, and no evidence for a reduction in risk for those taking cholesterol lowering medication.

[2399] Engelhart MJ, Geerlings MI, Ruitenberg A, van Swieten JC, Hofman A, Witteman JCM, Breteler MMB. Diet and risk of dementia: Does fat matter?. Neurology [Internet]. 2002 ;59(12):1915 - 1921. Available from: http://www.neurology.org/content/59/12/1915.abstract

http://www.eurekalert.org/pub_releases/2002-12/aaon-nsc121602.php

Cholesterol not a risk factor for Alzheimer's

Previously, the long-running, large-scale Framingham study found people with elevated levels of homocysteine in the blood had nearly double the risk of developing Alzheimer’s disease (AD). The study now clarifies the inconclusive results from previous studies regarding whether plasma cholesterol levels are associated with increased risk of Alzheimer disease (AD). They found that, after adjustment for age, sex, APOE genotype, smoking, body mass index, coronary heart disease, and diabetes, there was no significant association between AD risk and cholesterol level.

Tan, Z.S., Seshadri, S., Beiser, A., Wilson, P.W.F., Kiel, D.P., Tocco, M., D'Agostino, R.B. & Wolf, P.A. 2003. Plasma Total Cholesterol Level as a Risk Factor for Alzheimer Disease: The Framingham Study. Archives of Internal Medicine, 163, 1053-1057.
http://archinte.ama-assn.org/cgi/content/abstract/163/9/1053

New study counters previous research linking intake of dietary fat with increased risk of dementia

Previous studies suggesting that fat may be involved in the development of dementia and Alzheimer’s disease have been contradicted by a new study involving over 5,000 elderly people over a period of six years. The study found no correlation between fat and cholesterol intake and risk of dementia, and no evidence for a reduction in risk for those taking cholesterol lowering medication.

Engelhart, M.J., Geerlings, M.I., Ruitenberg, A., van Swieten, J.C., Hofman, A., Witteman, J.C.M. & Breteler, M.M.B. 2002. Diet and risk of dementia: Does fat matter?: The Rotterdam Study. Neurology, 59, 1915-1921.

http://www.eurekalert.org/pub_releases/2002-12/aaon-nsc121602.php

High calorie consumption associated with higher risk of Alzheimer’s in those genetically disposed to Alzheimer’s

980 elderly individuals without Alzheimer’s participated in a four-year study to investigate whether there was any link between caloric intake and Alzheimer’s. During the course of the study, 242 patients developed Alzheimer’s, and 28% tested positive for the APOE epsilon 4 gene. Participants were divided into four groups depending on how many calories they consumed daily. 263 of the participants tested positive for the APOE epsilon 4 gene, and among them, those who consumed the most calories had a 2.3 times greater chance of developing Alzheimer’s compared to those who ate the fewest calories. For those without the ApoE e gene, calorie and fat intake were not associated with a greater risk of Alzheimer’s.

[2405] Luchsinger JA, Tang M-X, Shea S, Mayeux R. Caloric Intake and the Risk of Alzheimer Disease. Arch Neurol [Internet]. 2002 ;59(8):1258 - 1263. Available from: http://archneur.ama-assn.org/cgi/content/abstract/59/8/1258

http://www.eurekalert.org/pub_releases/2002-08/jota-cmc081202.php

High blood pressure and cholesterol are risk factors for Alzheimer's disease

A large-scale Finnish study following 1449 men and women over 21 years found that raised systolic blood pressure and high serum cholesterol concentration, particularly in combination, in midlife, increase the risk of Alzheimer's disease in later life. Raised diastolic blood pressure had no significant effect.

The study was reported in the British Medical Journal. http://www.bmj.com/cgi/content/full/322/7300/1447

Cholesterol bad for brain too

An analysis of data on 1037 older women who had participated in a clinical trial of hormone replacement therapy found that high cholesterol levels increase the risk of cognitive impairment. It is speculated that, in addition to clogging arteries, and possibly leading to vascular changes in the brain, cholesterol may promote the clumping of a protein called beta-amyloid, which is believed to damage the brain in Alzheimer’s disease patients.

[2411] Yaffe K, Barrett-Connor E, Lin F, Grady D. Serum Lipoprotein Levels, Statin Use, and Cognitive Function in Older Women. Arch Neurol [Internet]. 2002 ;59(3):378 - 384. Available from: http://archneur.ama-assn.org/cgi/content/abstract/59/3/378

http://www.eurekalert.org/pub_releases/2002-03/uoc--cbf031302.php

Role of cholesterol in memory

It appears that cholesterol stimulates the nerve cells of the brain to make the connections that are essential to learning and memory, thus playing a crucial role in making sure that the brain works properly. But how does cholesterol do its job? The blood-brain barrier prevents the brain obtaining cholesterol from the blood. New research suggests that cholesterol is secreted by support cells (glial cells) within the brain. The research may lead to new strategies to cure injury- or disease-induced brain lesions, and suggests a new hypothesis concerning Alzheimer's disease.

[503] Barres BA, Smith SJ. Neurobiology. Cholesterol--making or breaking the synapse. Science (New York, N.Y.) [Internet]. 2001 ;294(5545):1296 - 1297. Available from: http://www.ncbi.nlm.nih.gov/pubmed/11701918

http://news.bbc.co.uk/hi/english/health/newsid_1645000/1645372.stm
http://www.eurekalert.org/pub_releases/2001-11/m-brd110401.php

High blood pressure and cholesterol are risk factors for Alzheimer's disease

A large-scale Finnish study following 1449 men and women over 21 years found that raised systolic blood pressure and high serum cholesterol concentration, particularly in combination, in midlife, increase the risk of Alzheimer's disease in later life. Raised diastolic blood pressure had no significant effect.

[1448] Kivipelto M, Helkala E-L, Laakso MP, Hanninen T, Hallikainen M, Alhainen K, Soininen H, Tuomilehto J, Nissinen A. Midlife vascular risk factors and Alzheimer's disease in later life: longitudinal, population based study. BMJ [Internet]. 2001 ;322(7300):1447 - 1451. Available from: http://www.bmj.com/cgi/content/abstract/322/7300/1447

http://www.bmj.com/cgi/content/full/322/7300/1447