Plasma cortisol secretion and REM period latency in adult endogenous depression.

The authors studied the relationship of plasma cortisol secretion and REM period latency in 25 patients with endogenous depression. The 8 patients (32%) with cortisol hypersecretion had a significantly shortened REM period latency in comparison with the 17 with normal cortisol secretion. Furthermore, an extremely short REM latency (20 minutes or less) occurred almost exclusively in those with cortisol hypersecretion. The authors discuss possible neurotransmitter disturbances responsible for these abnormalities and the clinical implications of these findings.