Higher Serum Melatonin Levels during the First Week of Malignant Middle Cerebral Artery Infarction in Non-Surviving Patients

Measuring serum melatonin concentrations to predict clinical outcome after aneurysmal subarachnoid hemorrhage

BACKGROUND

Oxidative stress has a key role in brain injury and melatonin possesses antioxidant effects. We aimed to ascertain the potential relationship between serum melatonin concentrations and functional outcome following aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

This prospective and observational study was conducted of 169 aSAH patients. Baseline serum melatonin concentrations were determined. A worse 6-month functional outcome was defined as a Glasgow Outcome Scale score of 1-3.

RESULTS

Patients with a worse outcome (56 cases) compared to those with a good outcome (113 cases) exhibited significantly higher concentrations of serum melatonin (P < 0.001). An area under the receiver operating curve of 0.819 was revealed for the prediction of 6-month worse outcome by serum melatonin concentrations. Multiple logistic regression analysis showed an independent association of serum melatonin concentrations with 6-month worse outcome (odds ratio = 1.204). An intimate correlation existed between serum melatonin concentrations and World Federation of Neurological Surgeons subarachnoid hemorrhage scale scores as well as between serum melatonin concentrations and modified Fisher scores (P < 0.001).

CONCLUSIONS

Patients with higher serum melatonin concentrations are more likely to have a poor prognosis. Serum melatonin can be considered as an independent predictor of functional outcome after aSAH.

Narrative review of sleep and stroke

Sleep disorders, such as sleep-disordered breathing (SDB), insomnia or restless legs syndrome (RLS), are common in the general population and after stroke. In some cases, sleep disturbances are pre-existing, but can also appear de novo as a direct consequence of brain damage or due to stroke-related complications. Furthermore, some sleep conditions may act as a risk factor of stroke. This review explores the available evidence of the two-way relationship between sleep and stroke. Cardiovascular physiological changes during sleep are described, as well as the evidence on the relationship between stroke and sleep duration, SDB, RLS, insomnia, excessive daytime sleepiness (EDS), and circadian rhythm alterations. Potential changes on sleep architecture, and the links that may exist between sleep and functional outcomes after stroke are also discussed. Importantly, sleep-related disturbances may be associated with worse stroke recovery outcomes and increased cerebrovascular morbidity. It is therefore relevant that the bidirectional association between stroke and sleep is taken into consideration by clinicians taking care of these patients. Future research may focus on this mutual relationship for a better understanding of the impact of stroke on sleep, the importance of sleep in stroke incidence and recovery, and have further evidence on treatment strategies that may improve functional outcome after stroke.