Serotonergic receptors in the midbrain correlated with physiological data on sleep apnea in SIDS victims

Background: Recently it has been reported that serotonin and related matters are associated with the sudden infant death syndrome (SIDS), which is still the main cause of postneonatal infant death. To further explore this claim, the correlation between serotonin receptors in the brainstem and sleep apnea in SIDS victims was investigated. Materials and methods: Among 27,000 infants studied prospectively to characterize their sleep–wake behavior, 38 infants died under 6 months of age including 26 cases of SIDS. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and duration of sleep apnea were analyzed. Brainstem material was collected and immunohistochemistry on 5-hydroxy tryptamine 1A (5HT1A) receptor was carried out. The density of 5HT1A receptor-positive neurons was measured quantitatively. Nonparametric analysis of the density of 5HT1A receptor-positive neurons was carried out between SIDS and non-SIDS cases. Correlation analyses were performed between the density of 5HT1A receptor-positive neurons and the data on sleep apnea. Results: There was no correlation between the pathological data on 5HT1A receptors and the physiological data on sleep apnea in SIDS victims. Conclusions: No correlation between pathological findings of serotonin and physiological findings of sleep apnea were not in agreement with the association of sleep apnea in pathophysiology of SIDS. [Copyright &y& Elsevier]