Alcohol consumption and the CAGE test in outpatients with schizophrenia or schizoaffective disorder and in the general population.

We conducted a survey of 151 outpatients with schizophrenia or schizoaffective disorder in Geneva, Switzerland, in 2000, and a mail survey in a representative sample of the general population of Geneva in 1996 (n = 742), to compare alcohol consumption and alcoholism in these two samples. Fewer patients with schizophrenia than participants in the general population drank alcohol daily (9.9% vs. 18.3%, p < 0.001). Excluding participants who said they currently never drank, alcohol consumption was similar in both groups (3 vs. 4 glasses/week, p = 0.22). However, more patients with schizophrenia than participants in the population sample had a CAGE score > or = 2 (21.2% vs. 10.1%, p < 0.001), indicating a suspicion of alcoholism. Thus, asking about alcohol consumption produced different results from assessing hidden alcoholism with the CAGE. Either patients with schizophrenia under-reported their alcohol consumption, or the CAGE produced higher scores in these patients, for any given level of alcohol consumption. Previous research has shown, however, that the CAGE is a valid test in patients with schizophrenia, which suggests that in Geneva, alcoholism is more prevalent in patients with schizophrenia than in the general population.