Sleep EEG and DST findings in anergic bipolar depression.

The authors report sleep EEG and dexamethasone suppression test (DST) findings for a homogeneous sample of anergic bipolar depressed outpatients (bipolar I, N = 7; bipolar II, N = 19) characterized by motor retardation, volitional inhibition, hypersomnia, or weight gain and sleep EEG findings for 26 age- and sex-matched normal control subjects. Sleep architecture was abnormal in bipolar depression, particularly with respect to little stage 1 sleep. The biological profile of an anergic episode of bipolar depression did not include a shorter than normal mean REM latency, poor sleep continuity, or abnormally low amounts of stages 3 and 4 sleep, and only three (13%) of 23 patients manifested cortisol nonsuppression.