[Treatment of depression with sleep deprivation and sleep phase advancement]

Total sleep deprivation (TSD) exerts beneficial but only transient effects on mood in approximately 60% of the patients with a major depressive disorder (MDD). The positive effect of TSD is generally reversed after the next night of sleep. A pilot study of our group indicated that a consecutive one week phase advance of the sleep phase stabilized mood in more than half of the patients who responded to TSD. However, the majority of patients in our pilot study had been treated concomitantly with antidepressive medication. To exclude a possible synergistic effect of simultaneous antidepressive medication and the sleep-wake manipulation in the present study eleven medicated and sixteen drug-free depressed patients were investigated. In two thirds of the patients relapse into depression after successful TSD could be prevented. This effect seemed to be independent of adjunct antidepressant pharmacotherapy. Ten of these patients were studied polysomnographically prior to and during the treatment. Data analysis revealed that during the advance of the sleep phase no prolonged partial sleep deprivation took place. At the end of the study REM % had even increased and REM latency was still short in spite of clinical improvement, thus contradicting the assumption that REM sleep suppression is a necessary prerequisite for antidepressive therapy. The results support the hypothesis of a "critical phase" in the morning hours during which sleep can reinduce depressive mood and, vice versa, prevention of sleep during this time may act antidepressively.