Maintenance of therapeutic effects of total sleep deprivation by limitation of subsequent sleep. A pilot study.

In a previous study it was shown that in endogenous depression repeated sleep deprivation (SD) during clomipramine treatment resulted in rapid improvement after each SD. However, except after the first night, relapses were observed after all sleep nights following SD (the "recovery nights"). The present pilot study had a therapeutic aim, namely to prevent these relapses. We were interested in whether limitation of sleep during the recovery nights might prevent these relapses and whether different amounts of sleep would have different effects on the course of mood after recovery sleep. Ten endogenously depressed patients were treated with clomipramine and with three SD's. Five patients slept for approximately 2 h, and the other five for about 5 h during the second and third recovery nights. On average, no relapse was shown by these patients and, in fact, there was some additional improvement after these nights, in contrast to the findings in the previous study, where patients were allowed unlimited sleep.