Role of Melatonin in the Management of Sleep and Circadian Disorders in the Context of Psychiatric Illness

Abstract

Purpose of review: We present a review of research on the role of melatonin in the management of sleep and circadian disorders, stressing current overall view of the knowledge across psychiatric disorders.

Recent findings: Dysregulation of sleep and circadian rhythms has been established in several psychiatric and neurocognitive disorders for long. Recent research confirms this finding consistently across disorders. The secretion of melatonin in schizophrenia and neurocognitive disorders is reduced due to a smaller volume and enlarged calcification of the pineal gland. On the other hand, melatonin dysregulation in bipolar disorder may be more dynamic and caused by light-sensitive melatonin suppression and delayed melatonin secretion. In both cases, exogenous melatonin seems indicated to correct the dysfunction. However, a very limited number of well-designed trials with melatonin to correct sleep and circadian rhythms exist in psychiatric disorders, and the evidence for efficacy is robust only in autism, attention deficit hyperactivity disorder (ADHD), and neurocognitive disorders. This topic has mainly not been of interest for recent work and well-designed trials with objective circadian parameters are few. Overall, recent studies in psychiatric disorders reported that melatonin can be effective in improving sleep parameters such as sleep onset latency, sleep efficiency, and sleep quality. Recent meta-analysis suggests that optimal dosage and dosing time might be important to maximize the efficacy of melatonin. The knowledge base is sufficient to propose well-designed, larger trials with circadian parameters as inclusion and outcome criteria. Based on the partly fragmentary information, we propose testing efficacy in disorders with neurocognitive etiopathology with later and higher dosing, and affective and anxiety disorders with lower and earlier dosing of melatonin. Melatonin is promising for the correction of sleep and circadian abnormalities in psychiatric disorders. However, research results on its effect are still few and need to be accumulated. For effective use of melatonin, it is necessary to consider the appropriate dosage and administration time, depending on the individual abnormality of sleep and circadian rhythms.

Keywords: Circadian disorder; Circadian rhythm; Melatonergic agents; Melatonin; Psychiatric illness; Sleep.

Fig. 1

Potential types of melatonin dysfunction and target effects of exogenous melatonin supplement according to dosage. In case of delayed melatonin rhythm, low-dose melatonin (≤ 1 mg) with earlier timing is needed to advance the melatonin rhythm for a chronobiotic effect. Meanwhile, in cases of blunted or dysregulated melatonin rhythms, high-dose melatonin usage (≥ 2 mg) with later timing would be better to enhance the melatonin rhythm and improve sleep disturbance for a soporific effect