Higher Intake Of Calories And Fat May Be Associated With Higher Risk Of Alzheimers Disease

Columbia Presbyterian Medical Center Study Shows Some Individuals May Have Higher Risk Than Others

NEW YORK, NY (August 14, 2002) — Researchers at Columbia University and the Columbia Presbyterian Medical Center of NewYork–Presbyterian Hospital suggest that a higher consumption of calories and fat may translate into an increased risk of developing Alzheimer’s Disease (AD) for some people.

The results of their study, reported in the August issue of Archives of Neurology, suggest that this risk may arise in individuals who have a variant of apolipoprotein E, known as apo E4. Apolipoprotein E (apo E) is a cholesterol-processing protein responsible for transporting cholesterol in and out of cells. There are different variants of apo E, designated by numbers. People inherit one form of apo E from each parent. Studies have shown that those with one copy of the variant apo E4 are at greater risk of developing AD, while those who inherit 2 copies are at even greater risk.

According to co-author, Dr. Richard Mayeux, Gertrude H. Sergievsky professor of Neurology, Psychiatry and Epidemiology at Columbia University College of Physicians & Surgeons and director of the Gertrude H. Sergievsky Center at Columbia University, “apo E4 is the single most important risk factor for late onset AD. Our study suggests that the effect of diet on the development of AD may be most robust for people with apo E4.”

The study examined the role of diet and AD risk in 980 individuals age 65 and over who were enrolled in the Washington Heights-Inwood Columbia Aging Project. Sixty-seven percent of the participants were female; 25 percent were Caucasian, 43 percent were Hispanic, and 32 percent were African-American. The mean age of participants was 75 years. All participants were assessed for AD and were found to be symptom-free.

Dietary data were obtained using a 61-item food frequency questionnaire. The mean reported intake of total calories was 1,265 for women and 1,316 for men, while the mean daily intake of fats was 38 grams. Participants were grouped by quartiles of calorie and fat consumption. The investigators reported 242 cases of AD during the mean observation of four years.

“Our analyses of these 242 cases showed that the risk of AD is associated with higher total caloric and fat intake in those individuals with either 1 or 2 copies of the apo E4 variant. In those without apo E4, caloric and fat intake were not associated with AD risk,” Dr. Mayeux said. “We don’t know if this apparent effect of diet on AD risk for apo E4 individuals is an additive or independent effect. That relationship remains to be fully determined,” he adds.

Study co-author Dr. Jose A. Luchsinger, assistant professor of medicine in the Division of General Medicine, researcher at the Taub Institute for Research on Alzheimer’s Disease and The Aging Brain, and assistant attending in medicine at NewYork-Presbyterian Hospital’s Columbia Presbyterian Medical Center, cautions that these early results do not translate into new dietary guidelines.

“The study of the relationship of diet and genes is just beginning—it’s still an area of early development. There already are good reasons to restrict fat and caloric intake, as many, many studies have shown beneficial effects in terms of cardiovascular disease and diabetes in an adult—but not elderly—population. It remains to be seen if this will hold true for the development of AD in the elderly.”

“Now that we’ve taken this first important step, we intend to further investigate the relationship of diet and AD risk in the elderly,” Dr. Mayeux said. “Our plan is to recreate this study by enrolling 2,500 AD-free participants, aged 65 and older, to follow them for 5 to 10 years to assess a full range of biological factors and AD risk.”

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Tags

AD, Columbia University, Richard Mayeux, Taub Institute