Simultaneous panic and depressive disorders: clinical and sleep EEG correlates.

Panic and depressive symptoms occur simultaneously in many depressed patients. To study the frequency of this association and to determine whether patients with simultaneous panic and major depression differed from those with only major depressive disorder (MDD) in clinical features and in sleep electroencephalographic (EEG) variables, we evaluated a total sample of 336 patients with MDD. Fifty-eight (17%) had both panic and MDD; 50 had complete data and were matched for age and severity of illness with other patients having only MDD. Patients with simultaneous panic and depression had significantly higher ratings for psychic and somatic anxiety, and rapid eye movement (REM) latencies approximating normal values. Patients with only MDD (without panic disorder) rated significantly higher in guilt feelings and had shorter REM latencies. Our results suggest that the simultaneous occurrence of panic and depression is relatively frequent, is accompanied by differences in sleep EEG variables, and may have implications for treatment.