Dexamethasone suppression test in primary depression: significance of family history and psychosis.

The overnight dexamethasone suppression test (DST) was administered to 31 inpatients with endogenous depression. DST results were abnormal in 42% of the group and in 67% of those patients with psychotic depression. Division of the sample into genetic subtypes based on family history criteria of Winokur et al. failed to replicate his group's DST findings. Subjects with sporadic depressive disorder, especially delusional patients, had a higher rate of dexamethasone nonsuppression than the others. Familial pure depressive patients did not show the expected greater frequency of DST abnormality compared to the depression spectrum disorder group.