Clinical Considerations Derived From the Administration of Melatonin to Children With Sleep Disorders.

BACKGROUND AND OBJECTIVES: Despite the numerous investigations carried out in relation to melatonin, there is a lack of knowledge about the specific melatonin secretion patterns in the diverse primary sleep disturbances. The objective of this study was to analyze the plasma melatonin concentrations in children with primary sleep disorders and the effects of melatonin therapy on their serum levels and their actigraphic sleep parameters. METHODS: Fourteen participants (nine girls; seven to 14 years old) diagnosed with diverse primary sleep disorders were recruited. Four different melatonin secretion patterns were identified: low plasma melatonin levels, absence of a circadian rhythm, advanced acrophase, and delayed acrophase. A placebo (one week) was administered followed by three months of melatonin therapy (3 mg/night). Urinary 6-sulfatoxymelatonin levels, 24-hour plasma melatonin concentrations, and a seven-day actigraphic record were collected after both treatments. RESULTS: After melatonin therapy, a significant increase (P < 0.001) of urinary 6-sulfatoxymelatonin excretion with a clear circadian variation was observed. Plasma melatonin concentrations were also significantly higher with a recovery in the circadian rhythm. Actual sleep time was significantly longer, with a substantial reduction in the sleep onset latency and night awakenings. No severe side effects were reported. CONCLUSIONS: The main clinical implication of this study is to demonstrate the efficacy of melatonin in three main circumstances: an insufficient hormone production, a disturbed circadian rhythm, and an advanced or delayed acrophase. As ongoing work, we are exploring the effect of different doses of melatonin on the regulation of its concentrations and of its secretion rhythm.

Analysis of Different Melatonin Secretion Patterns in Children With Sleep Disorders: Melatonin Secretion Patterns in Children.

The objective of this study was to analyze circadian patterns of urinary 6-sulphatoxymelatonin (aMT6s) excretion in children with primary sleep disorders in comparison with healthy controls. A total of 124 control children and 124 patients (aged 4-14 years) diagnosed with diverse primary sleep disorders were recruited. aMT6s concentrations were measured in diurnal and nocturnal urine, as well as in 24-hour urine. aMT6s levels were significantly higher and showed significantly more evident circadian variations in the control group ( P < .001). Four different melatonin (aMT) production and excretion patterns were distinguished in the group with sleep disorders: (1) standard aMT production pattern, (2) low aMT production pattern, (3) aMT production pattern with absence of circadian variation, and (4) aMT hyperproduction pattern. This study highlights the importance of analyzing specific alterations of aMT secretion in each sleep disorder and provides evidences to explain why not all children with sleep disturbances do respond to aMT treatment.

Methylphenidate effects on blood serotonin and melatonin levels may help to synchronise biological rhythms in children with ADHD.

UNLABELLED: The neuroendocrine mediators that may contribute to ADHD (Attention deficit and hyperactivity disorder), serotonin and melatonin, are both thought to regulate circadian rhythms, neurological function and stress response. The objective of this study was to determine the effect of the chronic administration of prolonged release methylphenidate (PRMPH) on daily variations in blood serotonin and melatonin and on the excretion of 6-sulphatoxy-melatonin. A total of 179 children (136 males, 42 females) between the ages of 5 and 14 (9.70 ± 2.55) years were enrolled in a controlled quasi-experimental open clinical study. Of the sample, there were 136 Children with ADHD (based on DSM-IV-TR criteria), who were further grouped into subtypes, and the 42 siblings of the participants who did not ADHD patients. Blood samples were taken at 20:00 and 09:00; urine was collected between 21:00 and 09:00. In the ADHD group, the study protocol was repeated after 4.61 ± 2.3 months of treatment. Measurements included melatonin and serotonin by RIA and urine 6-S-aMT by ELISA. Factorial analyses were conducted by STATA 12.0. RESULTS: ADHD patients showed reduced morning serotonin with a daily profile that was different than the control group due to the predominance of nocturnal concentrations. PRMPH did not result in any significant changes. Melatonin and its daily profile did not differ between controls and the ADHD group with a diurnal rhythm showing higher morning levels that disappear after PRMPH administration. Melatonin was higher in children with predominantly hyperactive-impulsive/conduct disorder subtype. PRMPH resulted in a decrease in 6-S-aMT excretion for both ADHD subtypes. CONCLUSION: Chronic treatment with prolonged release methylphenidate induces subtle changes in the daily fluctuations and concentrations of both serotonin and melatonin. Improvement in Children's Depression Inventory (CDI) scores was not related to a morning increase in serotonin.