Melatonin excretion in normal children and in tuberous sclerosis complex with sleep disorder responsive to melatonin

To determine normal melatonin excretion patterns in healthy children without sleep disorder and to compare these with those of patients with tuberous sclerosis complex and sleep disorder responsive to exogenous melatonin, we measured 6-sulfatoxymelatonin excretion in 21 healthy children and in 7 patients with tuberous sclerosis complex and sleep disorder responsive to melatonin (a 5 mg oral dose increasing total sleep time). Total excretion, cosinor percentage, and acrophase time of 6-sulfatoxymelatonin excretion were estimated. In normal children, total 6-sulfatoxymelatonin excretion was range 11.1 to 40.2 microg (mean 19.0 microg, SD 7.4 microg); cosinor percentage rhythm range was 52.9% to 100% (mean 87%, median 94%); and acrophase time range was 23 hours, 54 minutes to 10 hours, 42 minutes (mean 5 hours, 54 minutes; median 4 hours, 12 minutes). Fifth and 95th percentiles were 11.1 to 29.0 microg, 57.8% to 99.9%, and 2 hours, 1 minute to 10 hours, 4 minutes. In tuberous sclerosis, normal patterns of melatonin excretion were seen in responders. Circadian patterns of melatonin excretion were similar in children and adults. We propose that exogenous melatonin can act by a simple sedative action.