CO-MORBIDITY AND FAMILIAL AGGREGATION OF ALCOHOLISM AND ANXIETY DISORDERS

Background. This study examined the patterns of familial aggregation a nd co-morbidity of alcoholism and anxiety disorders in the relatives o f 165 probands selected for alcoholism and/or anxiety disorders compar ed to those of 61 unaffected controls. Methods. Probands were either s elected from treatment settings or at random from the community. DSM-I II-R diagnoses were obtained for all probands and their 1053 first-deg ree relatives, based on direct interview or family history information . Results. The findings indicate that: (1) alcoholism was associated w ith anxiety disorders in the relatives, particularly among females; (2 ) both alcoholism and anxiety disorders were highly familial; (3) the familial aggregation of alcoholism was attributable to alcohol depende nce rather than to alcohol abuse, particularly among male relatives; a nd (4) the pattern of co-aggregation of alcohol dependence and anxiety disorders in families differed according to the subtype of anxiety di sorder; there was evidence of a partly shared diathesis underlying pan ic and alcoholism, whereas social phobia and alcoholism tended to aggr egate independently. Conclusions. The finding that the onset of social phobia tended to precede that of alcoholism, when taken together with the independence of familial aggregation of social phobia and alcohol ism support a self-medication hypothesis as the explanation for the co -occurrence of social phobia and alcoholism. In contrast, the lack of a systematic pattern in the order of onset of panic and alcoholism amo ng subjects with both disorders as well as evidence for shared underly ing familial risk factors suggests that co-morbidity between panic dis order and alcoholism is not a consequence of self-medication of panic symptoms. The results of this study emphasize the importance of examin ing co-morbid disorders and subtypes thereof in identifying sources of heterogeneity in the pathogenesis of alcoholism.