Light-to-moderate alcohol consumption is associated with lower
risks of coronary heart disease, ischaemic stroke, and total mortality
in elderly men and women.Since evidence is increasing that vascular
disease is associated with cognitive impairment and dementia,research
is demonstrating that light-to-moderate alcohol intake might also
reduce the risk of dementia and Alzheimers disease. Conversely,
several studies suggested a neurotoxic effect of high amounts
of alcohol intake.
A population-based prospective study in Bordeaux, France, reported
an inverse association between wine consumption and the risk of
dementia. In this study, Monique Breteler et al hypothesised that
light-to-moderate alcohol intake was associated with a lower risk
of dementia, and aimed to quantify the relation between alcohol
consumption and the risk of dementia and subtypes of dementia;
specifically, and examined whether the effect varied by type of
Monique Breteler et al studied individuals taking part in the
Rotterdam Studya prospective population-based study of 7983 individuals
aged 55 years and older. All participants who did not have dementia
at baseline (1990-93) and who had complete data on alcohol consumption
(n=5395) were included. Through follow-up examinations in 1993-94
and 1997-99 and an extensive monitoring system, nearly complete
follow-up (99·7%) until the end of 1999 was achieved. Proportional
hazards regression analysis was used, adjusted for age, sex, systolic
blood pressure, education, smoking, and body-mass index, to compare
the risk of developing dementia between individuals who regularly
consumed alcohol and individuals who did not consume alcohol.
To check whether associations could be attributed to confounding,
analyses were repeated with possible confounders added to the
models (education, smoking, body-mass index, diabetes, and systolic
blood pressure). All analyses were repeated with dementia subtypes
(Alzheimers disease, vascular dementia) as the outcome.
The average follow-up was 6·0 years. During this period, 197 individuals
developed dementia (146 Alzheimers disease, 29 vascular dementia,
22 other dementia). Light-to-moderate drinking (one to three drinks
per day) was significantly associated with a lower risk of any
dementia and vascular dementia. No evidence was found that the
relation between alcohol and dementia varied by type of alcoholic
beverage. With increasing alcohol intake, the proportion of never
smokers and less-educated individuals sharply decreased. Beer
and liquor were mainly consumed by men. Fortified wine was mainly
consumed by women.
Compared with no alcohol consumption, light-to-moderate drinking
(one to three drinks per day) was associated with a significantly
lower risk of dementia. The effect of light-to-moderate drinking
seemed more prominent among men. There was no significant interactions
with age, smoking, or level of education.
These findings suggest that light-to-moderate alcohol consumption
is associated with a reduced risk of dementia in individuals aged
55 years or older. The effect seems to be unchanged by the source
of alcohol. the researchers found that, in a population aged 55
years or older, those who consumed up to three glasses of alcohol
per day had a lower risk of dementia and vascular dementia than
those who never drank alcohol
Several mechanisms could be responsible for the inverse relation
between consumption of up to three alcoholic drinks a day and
dementia. One possibility is that alcohol might act through reduction
of cardiovascular risk factors, either through an inhibitory effect
of ethanol on platelet aggregation, or through alteration of the
serum lipid profile. The findings that the lower risk was seen
mainly for vascular dementia is in agreement with this hypothesis.
A second possibility is that alcohol might have a direct effect
on cognition through release of acetylcholine in the hippocampus.
There is substantial evidence that acetylcholine facilitates learning
Previously, the PAQUID study in Bordeaux, France, reported that
wine consumption is associated with a lower risk of dementia,
but the Rotterdam data did not suggest a different effect of specific
types of alcoholic beverages beyond the effect of alcohol itself.
The observations are consistent with recent findings of the Canadian
Study of Health and Ageing.
Alcohol consumption and risk of dementia: the Rotterdam Study
Volume 359, Number 9303 26 January 2002 The Lancet Monique M B
Breteler et al Department of Epidemiology and Biostatistics s
Correspondence to: Dr Monique M B Breteler (e-mail:firstname.lastname@example.org)