Analysis of Plasma Orexin Levels in Pedıatrıc Migraine Patients: A Prospectıve Controlled Clinical Study

Abstract

Objective: Migraine is the most common primary headache disorder in children. However, its pathogenetic mechanisms are not fully understood. Researchers focused on Orexin A (a neuropeptide with anti-nociceptive effects) and Orexin B (a neuropeptide with pro-nociceptive effects), but the literature is scarce in terms of studies investigating the plasma levels of these neuropeptides in pediatric migraine patients. We aimed to compare the plasma levels of orexins between pediatric migraine patients and healthy controlsMethods: Children aged between 5 and 18 who were under diagnostic evaluation for and diagnosed with migraine in Ondokuz Mayıs University, Department of Pediatric Neurology between December 2018 and December 2019, constituted the target population. All study group patients (Group 1) were diagnosed with migraine according to IHS 2004 criteria. The control group (Group 2) consisted of healthy children. Data including age, gender, and presence or absence of aura were recorded. Two blood samples were taken from the patients in Group 1. The first sample was withdrawn during a non-attack period, and the second sample was withdrawn during the initial migraine attack. Only one blood sampling was done in the control group. Plasma Orexin A and Orexin B levels were analyzed by radioimmunoassay and compared between Group 1 and Group 2 during non-attack and attack periods. Also, intra-group comparative analyses were performed. Non-parametric tests were used for statistical analysis.Results: This study included 98 patients, 52 children with migraine (Group 1), and 46 healthy children (Group 2). Mean patient age was 12,5±3,1 year in Group 1 and 12,3±3,4 years in Group 2. There was no difference between patient groups in terms of gender (p=0,103) and age (p=0,734). Plasma Orexin A levels of the migraine patients were higher than control group participants during the non-attack period, while Orexin B levels of the migraine patients were higher than migraine patients during the attack period. The mean plasma Orexin A level was significantly higher during the non-attack period than the attack period (p=0,002). The mean plasma Orexin B level was significantly higher during the attack than in the non-attack period (p=0,002). The presence of aura did not impact plasma orexin levels during both attack and non-attack periods.Conclusions: The plasma level of Orexin A is elevated in migraine patients, probably as a response to nociceptive signals, and migraine attack is associated with elevated plasma Orexin B levels. Targeting the orexinergic system seems like a reasonable approach to improving the treatment of migraine disease.