Schizo-affective disorder, manic type. A clinical, laboratory, and genetic study.

We studied a sample of 111 Feighner manics divided into 42 'pure' manics without any schizophrenic features, 41 manics with one such feature, and 28 with two or more such features. The three groups did not significantly differ on any major demographic, clinical, historical, treatment response, laboratory, or familial variable tested. We also applied the DSM-III schizophrenia and schizophreniform criteria to these 111 Feighner manics. Only 1 manic had an index episode longer than 6 months (a necessary criterion for schizophrenia), whereas 13 (12%) satisfied the schizophreniform criteria. We compared these 13 Feighner manics satisfying DSM-III schizophreniform criteria with the remaining 97 Feighner manics and could find no major demographic, clinical, or laboratory differences between the two groups. Although not statistically significant, the morbidity risk for affective disorder in the first-degree relatives of the 97 Feighner manics was three times the risk in the relatives of the Feighner manics who also satisfied the DSM-III schizophreniform criteria. The morbidity risk for alcoholism in these relatives was one-half that of first-degree relatives of the 'schizophreniform' manics. The two groups did not differ in total risk for alcoholism and affective disorder.