Addition of melatonin to hypothermia therapy for neonatal hypoxic-ischemic encephalopathy

Introduction: Neonatal hypoxic-ischemic encephalopathy is caused by perinatal asphyxia, resulting in an acute neurological dysfunction of variable severity. It occurs in one to six of every 1000 full-term newborns and is associated with high neonatal morbimortality and adverse neurological outcomes. The use of hypothermia is considered the standard therapy for this condition. However, different adjuvant therapeutic options have been proposed due to limited clinical efficacy, including drugs like melatonin. There is controversy about whether combined therapy with melatonin is superior to monotherapy with hypothermia. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, and Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of the findings table using the GRADE approach. Results: We identified two systematic reviews that included two primary studies, both randomized trials. The two randomized trials were included in the analysis of the present work. Conclusion: It is not possible to establish whether the addition of melatonin decreases mortality or the probability of alterations in brain magnetic resonance imaging because the certainty of the existing evidence has been assessed as very low. On the other hand, the addition of melatonin to hypothermia therapy, compared to hypothermia monotherapy, may increase the probability of normal neurological examination at six months and the probability of normal cognition at 18 months. Finally, adding melatonin to hypothermia therapy likely reduces the probability of seizures.