Am J Psychiatry 1990; 147:1199-1202
Copyright © 1990 by American Psychiatric Association
Comorbidity of major depression and anxiety disorders in twin pairs
S Torgersen
Department of Psychology, University of Oslo.
The relationship among major depression only, major depression with anxiety
disorders, and anxiety disorders only was investigated in a twin sample (N
= 177 pairs). The results suggest that there is an etiological relationship
between mixed major depression-anxiety disorders and major depression only
but no relationship between these two conditions and anxiety disorders
only. When anxiety disorders with panic attacks were analyzed, the
relationship between mixed cases and major depression only and the lack of
a relationship between mixed cases, major depression only, and anxiety
disorders only became even clearer. Furthermore, mixed cases seemed to be
more strongly influence by genetic factors than was major depression only.
