Alcoholism and dementia

There is little doubt that excessive consumption of alcohol over a considerable period of time leads to an impairment of cognitive function. Specific alcohol-related disorders such as the Wernicke–Korsakoff syndrome, hepatic encephalopathy, and pellagra cause clinical dementia syndromes but when these have been excluded there is still a considerable number of alcoholics who can be classified as demented. The Liverpool Longitudinal Study of mental health of the elderly residing in a community dwelling found that dementia was 4.6 times more likely to occur in men aged 65 and older who had a lifetime history of heavy drinking (Saunders et al., 1991). A more recent epidemiological study of older African-American men found that increasing alcohol consumption was associated with a worsening performance on dementia screening scales (Hendrie et al., 1996). In a sample of 130 cognitively impaired residents of long-term care facilities, alcohol-related dementia comprised 24% of this population compared with Alzheimer's disease (35%), vascular dementia (19%), and other causes (22%) (Carlen et al., 1994). The most commonly used clinical definition of alcohol-related dementia is given in the Diagnostic and Statistical Manual Version IV (DSM IV) (Frances, 1994). This definition requires the presence of dementia that, in the opinion of the clinician, is intrinsically linked to the abuse of alcohol. The diagnostic criteria are vague and subjective and there have been no published validation or reliability reports using these criteria. Two recent papers dealing with operational diagnostic criteria in alcohol-related disorders might help clarify the issue.