South Westminster schizophrenia survey. Alcohol use and its relationship to symptoms, tardive dyskinesia and illness onset

In the context of a prevalence survey of schizophrenia in South Westminster, a questionnaire was administered to 271 patients to assess alcohol-related morbidity. In this epidemiologically based sample, the lifetime prevalence of alcohol abuse was 22.1%. Compared with control patients matched for age and sex, these index cases had a significantly shorter duration of illness. A possible explanation is that drinking may mask the onset of schizophrenia, leading to a delay in diagnosis. The index cases also had significantly higher ratings for hallucinations and for hostility, anxiety and depression, and a greater number of disturbed types of behaviour. The highest levels of alcohol consumption were associated with more severe orofacial dyskinesia, suggesting that alcohol use may be an added risk factor for the development of tardive dyskinesia in some patients. The severity of akathisia was also related to alcohol use, and there were significant relationships between the subjective distress related to akathisia and the level of abuse. A possible interpretation is that alcohol had been used by patients with akathisia to alleviate the associated agitation and dysphoria.