To Your Good Health: Assessing Alzheimer’s Risk
Dear Dr. Roach: My wife and her two siblings all have Alzheimer’s disease. My wife is 81 and now lives in a nursing home. Her sister is 86 and in hospice, and their brother died at age 80. What is the risk of getting Alzheimer’s if a family member has it? — Anon.
Answer: Alzheimer’s disease is a common cause of dementia, the impairment of memory and other cognitive brain function, such as decision-making ability. The biggest risk factor for Alzheimer’s disease is age, with the rate of Alzheimer’s roughly doubling every five years after age 65. Having a first-degree relative (a parent or sibling) who has it increases the risk of developing Alzheimer’s disease at any age; the absolute increase in risk can be as much as 30 percent higher. The risk appears to be even higher for blacks. However, the older the relative at the time of diagnosis, the less the increased risk for the family member. So, having a family history definitely increases the risk but doesn’t guarantee diagnosis.
Although there are genetic tests currently available, I don’t recommend them at this time. They don’t accurately predict who will and won’t develop Alzheimer’s disease: They only can point to an increased or decreased risk.
The Alzheimer’s Association, at www.alz.org, has an outstanding website with many resources.
Dear Dr. Roach: I read your column regularly, as it is printed in my local newspaper.
Although I make no claims to be a physician, I have studied health and nutrition for more than 30 years. I sometimes find that your responses to questions regarding heart attacks and strokes consist of medication and surgery. Why do you not inform people that cholesterol is the culprit when it comes to clogging arteries, and that a diet free of animal protein will eliminate cholesterol problems?
The enormous amount of research and data compiled make a compelling argument for humans to adopt a plant-based diet. — S.A-K.
Answer: First off, I agree with you that a plant-based diet is likely to prevent many diseases, and I may not have emphasized diet often enough in this column. However, cholesterol is not the only culprit in vascular disease, and it is clear that even strict vegetarians can develop blockages in their heart and other blood vessels. An interesting study of the blood vessels of ancient humans suggests that the rates of atherosclerosis were similar thousands of years ago, and are present in all cultures, including those whose diets were mainly meat-based, grain-based or plant-based.
Secondly, prevention is different from treatment. By the time someone has had a heart attack or stroke, the evidence is absolutely clear that medication treatment, with statin drugs, aspirin or other platelet drugs and ACE inhibitor or similar medication reduces overall risk of death. Even so, it’s NEVER too late to adopt a healthier diet. As you suggest, a diet high in animal protein (and animal fat) is clearly associated with increased health risks. There is evidence that changing diet radically can stop things from getting worse and even can reverse damage. In the short term, medications still may be necessary, but many people are able to stop taking medicines if the diet works for them.
There are ethical and ecological reasons as well for a plant-based diet.
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or write to P.O. Box 536475, Orlando, FL 32853-6475.