STOCKHOLM — Individuals who carry the apolipoprotein E ϵ4 allele that increases the risk of developing Alzheimer's disease may lower their risk to that of a noncarrier through regular exercise, moderate fat intake, and low alcohol consumption, reported Tiia Ngandu at the 12th Congress of the International Psychogeriatric Association.
Ms. Ngandu and her associates studied 1,449 Finnish people who participated in the longitudinal, population-based Cardiovascular Risk Factors, Aging, and Dementia study (CAIDE) in 1972, 1977, 1982, or 1987. After an average follow-up of 21 years, the participants were aged 65–79 years when they were reexamined in 1998.
Based on questions answered at midlife, active individuals (exercised at least twice per week) who carried the ϵ4 allele of apolipoprotein E (apo E) had a significantly lower likelihood of developing Alzheimer's disease (AD) than sedentary carriers, said Ms. Ngandu, a doctoral student at the Aging Research Center at the Karolinska Institute, Stockholm.
Intake of polyunsaturated fatty acids did not alter the odds of developing AD in carriers, but high intake of saturated fatty acids was associated with significantly greater odds of AD in carriers, compared with a low intake.
Apo E ϵ4 carriers who frequently consumed alcohol had a significantly higher likelihood of developing AD than carriers who drank infrequently or never.
None of the lifestyle factors reduced the risk of AD in noncarriers, she noted.
“Carriers seem more vulnerable to various environmental effects,” she said.
People with a parent with late-onset Alzheimer's disease may undergo genotyping for apo E. A positive finding is not diagnostic of Alzheimer's disease, even in a symptomatic patient. The test also is done in some patients with both high cholesterol and elevated triglycerides to determine whether the patient's lipid disorder has a genetic component.