Evaluation of The Impact of Hypocretin Receptor 1 rs2271933 Polymorphism on Sleep Components in Chronic Migraine Patients with Poor Sleep Quality: A Subgroup Analysis.

INTRODUCTION: Long-reported dual comorbidity between migraine and sleep disorders suggests that some gene variations may play a role in this relationship. Our previous study found an association between poor sleep quality and the G allele of the hypocretin receptor 1 (HCRTR1) rs2271933 gene in patients with chronic migraine (CM). This study aimed to examine the relationship of this gene with some sleep parameters. METHODS: The present study was designed cross-sectional in the Mersin University Neurology Clinic between January 2000 and February 2018. Patients aged 18-75 years with CM according to the International Classification of Headache Disorders-3 (ICHD-3) criteria were included. The Pittsburgh Sleep Quality Index (PSQI) was used to evaluate the sleep quality of the patients. Patients were divided into two groups according to PSQI scores <6 or ≥6. Genotyping was performed for the HCRTR1 rs2271933 gene. RESULTS: Among the 100 patients with CM, only the data of those (n=67) with poor sleep quality were included in this study. The mean age of patients was 40.9±11.8%, and the female rate was 89.6%. We detected that increasing the time to fall asleep (p=0.369) and the rate of poor sleep quality (p=0.461) and also shortening sleep duration (p=0.016) with the increase of G allele carrier of HCRTR1 rs2271933 gene. CONCLUSION: As the G allele carrier of the HCRTR1 rs2271933 gene increased, a shorter sleep duration was observed. This finding may contribute to studies on the physiological roles of orexins.