Introduction: A previous case-report described one individual whose significant sleep disturbance in association with septo-optic dysplasia (SOD) was corrected with melatonin administration. Subsequently a trial of melatonin treatment in children with SOD and sleep disruption has become accepted clinical practice in many centres. There are however no published data describing melatonin secretion in these individuals.
Methods: We studied six children with sleep disturbance associated with SOD (characteristics in table below), all of whom were on adequate hormonal replacement at the time of investigation. All children wore an actiwatch-mini for two weeks and were admitted to hospital for a 24 h period during which hourly measurements of serum melatonin were taken. Sleep data were analyzed in conjunction with a detailed sleep diary completed by the children’s parents over the 2-week period. Ethical approval was obtained for these studies.
Results: Actigraphic studies showed reduced sleep efficiency in all children, mainly due to frequent and often prolonged night awakenings. Only one child (1) presented with a free-running sleep pattern with incremental asynchrony suggesting a non-24-h sleep–wake disorder. Melatonin profiles of all children showed a normal circadian rhythm with mean serum levels being lowest in the day (mean 56 pg/ml) and peaking overnight (mean 380 pg/ml).
Conclusions: These findings indicate that abnormalities in timing and amount of melatonin secretion do not account for the significant sleep abnormalities observed in these children, suggesting that other as yet unexplored factors are contributing to their abnormal sleep patterns.