Tiia A, Helkala E, Viitanen M, et al: Alcohol drinking in middle age and subsequent risk of mild cognitive impairment and dementia in old age: a prospective population-based study. BMJ,doi:10.1136/bmj.38181.48958.BE (published 10 August 2004)
These researchers used a large prospective study of a population in Finland to examine the interaction of alcohol use in midlife, mild cognitive impairment, and dementia in old age, and the impact on risk of apolipoprotein E. Of 1,464 men and women aged 65 to 79 years, about 70% were reexamined after an average follow-up of 23 years. Thirty percent of the participants never drank alcohol, 40% drank infrequently (less than once a month), and 30% drank frequently (several times a month). Participants who drank no alcohol and those who drank alcohol frequently were twice as likely to have mild cognitive impairment in old age as those who reported infrequent alcohol use. Compared with noncarriers of the apolipoprotein E4 allele who never drank alcohol, the increased odds of developing dementia were 2.3 for infrequent drinkers and 3.6 for frequent drinkers who carried the apolipoprotein E4 gene. Those who were not carriers of apolipoprotein E4 had similar dementia risks regardless of drinking category.Although this study is limited by its imprecise characterizations of the amount of alcohol consumed, it is strengthened by its prospective design and long follow-up time. It appears that frequent alcohol drinking in middle age is associated with cognitive impairment in later life, but for this drinking to be associated with increased risk of dementia, the presence of the apolipoprotein E4 allele may be necessary.