Alcohol use disorders (AUDs) represent significant comorbidity in schizophrenia. Previous reviews have reported a wide range (12-55%) of dual diagnosis prevalence: however, there is no agreement on overall prevalence. Our aim is to present recent studies of AUD, estimate overall prevalence, and study characteristics affecting the prevalence of AUD.

We conducted a search using three electronic literature databases and a manual search on articles published in 1996-2007. Metaregression was used to study how prevalence is affected by different study characteristics.

Altogether 58 studies met our criteria. the median of current AUD prevalence was 10.1% (IQR=4.6-24.5, 19 studies) and median of lifetime AUD prevalence 22.2% (IQR= 12.1-32.0, 45 studies). in studies using DSM-III-R the median prevalence was higher than in studies using DSM-IV, ICD-9 or ICD-10 (32.3/18.1/10.3/5.9%).

Our systematic literature search found a wide range of prevalence estimates of AUD in schizophrenia patients. Approximately every fifth schizophrenia patient had AUD diagnosis. When contrasted to studies published between 1990-95 our results show a descending trend in AUD prevalence: however, AUDs are still common in schizophrenia patients. the decrease may be explained by changes in diagnostic systems, although it is also possible that other addictive substances, such as cannabis, have replaced alcohol in some countries. other sample characteristics did not affect to the prevalence estimates.