Risk Factors

Risk Factors

relative to Brain Aging and Medicinal Applications for

Alzheimer’s Disease

This page is a compilation of a few Alzheimer’s Disease Risk Factors of which you should be aware. Thought at this time Alzheimer’s Disease has no known cure, there are a number of factors you can entertain which may delay its onset and/or perhaps lessen a predisposition to the Disease.

 

 


RISK FACTORS

DISCLAIMER: This information is offered purely as a prompt suggesting the reader take whatever appropriate steps he or she deems necessary in order to acquire more complete education pertinent to Alzheimer’s Disease. To the best of my knowledge, any and all statements throughout this website have not been evaluated by the Food and Drug Administration, the AMA or any medical professional other than the author of the piece you might read or watch. Any suggestions made or product identified on this website are not intended to diagnose, treat, cure or prevent any disease.

 

 

Article Furnished by… www.worldhealth.net

 

Literature Review 2009
Risk Factors

Compiled by Dr. Ronald Klatz, M.D., D.O., President, and Dr. Robert Goldman, M.D., Ph.D., D.O., FAASP, Chairman – The American Academy of Anti-Aging Medicine (A4M) As a Public Information Service

 

 

Long Hours At Work May Raise Risk of Dementia

In that some studies have identified workplace stress as a contributing factor to poor general health, a Finnish study finds that long hours at work may be bad for mental functions. Marianna Virtanen, from the Finnish Institute of Occupational Health (Finland), and colleagues studied 2,214 British civil servants, in full-time employment at the study’s start (1997-1999), and followed-up five years later (2002-2004). A battery of cognitive tests (short-term memory, Alice Heim 4-I, Mill Hill vocabulary, phonemic fluency, and semantic fluency) were measured at the study’s start (baseline) and at follow-up. Compared with working 40 hours per week at most, working more than 55 hours per week was associated with lower scores in the vocabulary test at both baseline and follow-up. Long working hours also predicted decline in performance on the reasoning test (Alice Heim 4-I). Conclude the researchers: “This study shows that long working hours may have a negative effect on cognitive performance in middle age.”

[Virtanen M, Singh-Manoux A, Ferrie JE, Gimeno D, Marmot MG, Elovainio M, Jokela M, Vahtera J, Kivimäki M. “Long working hours and cognitive function: the Whitehall II Study.” Am J Epidemiol. 2009 Mar 1;169(5):596-605. Epub 2009 Jan 6.]

Low Vitamin D Correlates to Higher Risk of Dementia

A number of studies have established a wide range of health benefits for Vitamin D, deficiencies of which have been correlated to osteoporosis, autoimmune diseases, cardiovascular diseases, infectious diseases, and some types of cancers. Iain Lang, from Peninsula Medical School (United Kingdom), and colleagues studied 1,776 men and women ages 65+, assessing levels of cognitive function and sampling blood markers of vitamin D. The team found that people with normal cognitive function had higher levels of a blood marker for Vitamin D, as compared to study subjects with cognitive impairments. Further, those with the lowest Vitamin D markers were four-times more likely to be cognitively compromised. Observes the team: “This is the first large-scale study to identify a relationship between Vitamin D and cognitive impairment in later life.”

[Llewellyn DJ, Langa K, Lang I. “Serum 25-Hydroxyvitamin D Concentration and Cognitive Impairment,“ J Geriatr Psychiatry Neurol. 2008 Dec 10. [Epub ahead of print].

Diabetes Slows Some Aspects of Cognitive Function

Type-2 diabetes is a leading cause of long-term dependence and disability., and a new study has found the condition may slow some aspects of mental function. Roger Dixon, from the University of Alberta (Canada), and colleagues conducted a study of 465 diabetic men and women, ages 55 to 81 years old. They found that the diabetic subjects did just as well as healthier counterparts on tests of memory, fluency, reaction time, and perceptual speed, they performed worse on some tests of executive functioning. Specifically, the diabetic study participants were not as quick on sentence completion, and took longer to answer on tests of verbal comprehension. The researchers speculate that because diabetes impacts blood vessels, including those in the brain, the disease may cause these declines in cognitive performance.

[Yeung, Sophie E.; Fischer, Ashley L.; Dixon, Roger A. “Exploring effects of type 2 diabetes on cognitive functioning in older adults.” Neuropsychology. Vol 23(1), Jan 2009, 1-9.]

Lifetime Lead Exposure Causes Cognitive Deficits In Aging

Whereas it is established that the developing brain is especially susceptible to lead toxicity, a new study finds the aging brain is likewise vulnerable as well. In a 22-year long study involving exposure to lead in an occupational setting, Lisa A. Morrow, from the University of Pittsburgh (Pennsylvania, USA), and colleagues have found that cumulative exposure to lead had a significant negative impact on cognitive scores, particularly affecting spatial ability, learning, and memory. The team found that in lead-exposed workers, the effect of lead on overall cognition was 17% greater than for those without occupational exposure. Conclude the researchers: this and previous studies “support the inference that past history of occupational lead exposure may lead to longer term, possibly progressive, effects on cognitive decline as a function of cumulative dose.”

[Khalil N, et al "Association of cumulative lead and neurocognitive function in an occupational cohort" Neuropsychology 2009; 23: 10-19.]

Brain Age Predicts Dementia

Alzheimer’s Disease (AD) is characterized by deposits of amyloid plaques and neurofibrillary tangles in the brain. Gary Small, from the University of California, (USA) and colleagues conducted PET brain scans on 76 study subjects, each of whom was injected with a tracer to identify the locations of plaques and tangles. The team found that older age correlated with higher concentrations of the marker found in the medial and lateral temporal regions of the brain, areas involved with memory. The researchers also found that in the 34 subjects who also carried the APOE-4 gene, which elevates the risk of developing AD, the marker deposited also in the frontal region of the brain.

[Small GW, Siddarth P, Burggren AC, Kepe V, Ercoli LM, Miller KJ, Lavretsky H, Thompson PM, Cole GM, Huang SC, Phelps ME, Bookheimer SY, Barrio JR. “Influence of cognitive status, age, and APOE4 genetic risk on brain FDDNP positron-emission tomography imaging in persons without dementia.” Arch Gen Psychiatry. 2009 Jan;66(1):81-7.]

Electrical Towers and Alzheimer’s Risk

Dementia, including Alzheimer’s Disease (AD), is thought to be caused by a combination of genetic and environmental factors. Matthias Egger, from Bern University (Switzerland), and colleagues studied data from 4.7 million people enrolled in the Swiss National Cohort (linking mortality and census data), for the period 2000-2005. The team found that those people who lived within 150 feet (50 meters) of an electrical tower were 24% more likely to die from dementia (as compared to those who lived more than 2,000 feet (600 meters) away. The risks for AD also increased with the length of time that people spent near electrical towers. Those who lived in a tower’s shadow for more than 10 years were 78% more likely to die from dementia, and twice as likely if they lived there for more than 15 years.

[Huss A, Spoerri A, Egger M, Röösli M; for the Swiss National Cohort Study. “Residence Near Power Lines and Mortality From Neurodegenerative Diseases: Longitudinal Study of the Swiss Population.” Am J Epidemiol. 2008 Nov 5; [Epub ahead of print].

Heart Disease Is Linked to Worse Mental Function & Predicts Dementia

Archana Singh-Manoux, from the University College London (United Kingdom), and colleagues completed a study of 5,837 middle-aged participants in the Whitehall study, which began in 1985 and consists of a group of civil servants working in the Whitehall region of the United Kingdom. The researchers found that coronary heart disease is associated with a worse performance in mental processes such as reasoning, vocabulary, and verbal fluency. The study also found that the longer ago the heart disease had been diagnosed, the worse was the person’s cognitive performance, an effect that was particularly marked in men.

[Singh-Manoux A, Sabia S, Lajnef M, Ferrie JE, Nabi H, Britton AR, Marmot MG, Shipley MJ. “History of coronary heart disease and cognitive performance in midlife: the Whitehall II study.” Eur Heart J. 2008 Jul 22; [Epub ahead of print].]

Diabetes Linked to Cognitive Decline

Olivia Okereke, from Harvard Medical School (Massachusetts USA), and colleagues, analyzed data from 5,907 men participating in the Physicians’ Health Study II (average age 74.1 at the study’s start) and 6,326 women in the Women’s Health Study (average age 71.9 at the study’s start). The researchers found that men and women with diabetes performed more poorly on the initial cognitive tests, then also showed a more marked decline on subsequent tests. In addition, study subjects with longer-standing diabetes tended to be in worse cognitive condition at the study’s start, and showed a steeper decline over time. The team suggests that diabetes fuels mental decline because the condition can damage the blood vessels that supply the brain, diminishing blood flow. In addition, people with diabetes have chronically elevated levels of insulin, a hormone for which some studies show boosts the body’s levels of amyloid-beta protein, which is involved in the plaques formed in Alzheimer’s Disease.

[Okereke OI, Kang JH, Cook NR, Gaziano JM, Manson JE, Buring JE, Grodstein F. “Type 2 diabetes mellitus and cognitive decline in two large cohorts of community-dwelling older adults.” J Am Geriatr Soc. 2008 Jun;56(6):1028-36. Epub 2008 Apr 1.]

Excess Weight Increases Age-Related Cognitive Decline

Industrialized countries have witnessed an alarming rise in obesity, and in these nations the numbers of cases of cognitive decline, diagnosed as dementia, is on the rise. Youfa Wang, from Johns Hopkins University (Maryland, USA), and colleagues conducted a meta-analysis involving data resulting from 10 independent studies. The researchers found that obesity, or having a body mass index of 30 or higher, increased a person’s risk of dementia by more than 40%. Obesity was found to have a particularly strong effect on Alzheimer’s Disease, increasing the risk of that disorder by 80%.

[Beydoun MA, Beydoun HA, Wang Y. “Obesity and central obesity as risk factors for incident dementia and its subtypes: a systematic review and meta-analysis.” Obes Rev. 2008 May;9(3):204-18. Epub 2008 Mar 6.]

Diabetes Increases Risk of Alzheimer’s Disease

Previous studies have shown that diabetes is a risk factor for Alzheimer’s Disease (AD). Dave R. Schubert, from The Salk Institute For Biological Studies (California, USA), and colleagues have now identified the molecular connection between the two diseases. In a study involving lab animals, diabetes was found to damage blood vessels in the brain by the interaction of elevated blood glucose levels (characteristic of diabetes) and low levels of beta-amyloid protein (the protein suspected to cause the plaques characteristic in AD). The researchers observe that: “While all people have a low level of amyloid circulating in their blood, in diabetics there may be a synergistic toxicity between the amyloid and high level of blood glucose, that leads to the problems with proper blood vessel [function].”

[Burdo JR, Chen Q, Calcutt NA, Schubert D. “The pathological interaction between diabetes and presymptomatic Alzheimer's disease.” Neurobiol Aging. 2008 Mar 25; [Epub ahead of print].]

High Cholesterol in Your 40s Increases Risk of Alzheimer’s Disease

People with high cholesterol in their early 40s are more likely to develop Alzheimer’s Disease (AD), as compared to those with low cholesterol. Rachel Whitmer, from Kaiser Permanente Division of Research (California USA), and colleagues studied 9,752 men and women who underwent health evaluations in the 1960s and 1970s when they were between the ages of 40 and 45. Then between 1994 and 2007, the team obtained the most recent medical records for group, finding that 504 of the study participants were diagnosed with Alzheimer’s Disease and 162 with vascular dementia. Those with total cholesterol levels between 249 and 500 mg were 1.5-times more likely to develop AD than those with levels of 198 or less. People with cholesterol levels of 221 to 248 mg were more than 1.25-times more likely to develop AD. The researchers conclude that: “High mid-life cholesterol increase[s] the risk of Alzheimer’s Disease regardless of diabetes, blood pressure, obesity, smoking, and stroke [later in life].”

[Whitmer R. et al. Presented at the 60th Annual Meeting of the American Academy of Neurology, April 16, 2008.]

Belly Flab in 40s Raises Alzheimer’s Risk in 70s

Rachel Whitmer, from the Kaiser Permanente Division of Research, Etiology and Prevention (California, USA) and colleagues tracked 6.583 men and women residing in northern California, for an average of 36 years, starting when they were ages 40 to 45. A total of 1,049 of them – nearly 16% –developed Alzheimer’s Disease (AD) or dementia when they reached their 70s. Those subjects in the upper 20% in terms of belly size in middle-age were almost three times more likely to develop dementia./AD than the study participants who were in the lowest 20% of belly size. The team found that having a large belly raised one’s risk of dementia regardless of whether the person was of normal weight overall, overweight, or obese, and regardless of health conditions such as diabetes, stroke, and heart disease.

[Whitmer RA. “The epidemiology of adiposity and dementia.” Curr Alzheimer Res. 2007 Apr;4(2):11722.]

B-Vitamin Deficiencies Increase Dementia Risk

JM Kim, from Chonnam National University Medical School (Korea), and colleagues completed a study of 518 men and women, average age 74, for 2.4 years. They team found that dementia occurred more commonly in those with a decline in folate, with folate deficiency correlated to a 3.5-time increase in the likelihood of developing the disease. Additionally, the researchers found low concentrations of vitamin B-12 to be associated with the risk of dementia.

[Kim JM, Stewart R, Kim SW, Yang SJ, Shin HY, Shin IS, Yoon JS. “Changes in folate, vitamin B12, and homocysteine associated with incident dementia.” J Neurol Neurosurg Psychiatry. 2008 Feb 5; [Epub ahead of print].]


 

 

Provided below is an offering of a few topics you may wish to review.