Serum melatonin levels are associated with mortality in patients with malignant middle cerebral artery infarction

Ischaemic stroke causes mortality, disability, and consumption of health resources.1 In cerebral infarction, there is cell death due to brain obstruction of the vasculature, which limits the supply of blood containing vital oxygen and substrates for neurons. Additionally, there can be a secondary injury due to different mechanisms, such as oxidative stress, inflammation, and apoptosis, which could contribute to increase cell death.2–6 Administration of melatonin on traumatic brain injury can have different beneficial effects, such as anti-oxidant, anti-inflammatory, and anti-apoptotic effects.7–9 Melatonin levels in patients with ischaemic stroke have not been well determined.10–15 Lower urinary levels of melatonin and/or its metabolite 6-sulfatoxymelatonin,10–14 and lower serum melatonin levels15 have been found in patients with ischaemic stroke compared with healthy controls. Therefore, this study aimed to determine whether serum melatonin levels are associated with peroxidation status, antioxidant status, and mortality in patients with ischaemic stroke.