Clinical characteristics and patient-reported outcomes of chronic and episodic migraine patients at a US tertiary headache center: A retrospective observational study.

Abstract

To describe differences in clinical and demographic characteristics between patients with episodic migraine (EM) or chronic migraine (CM) and determine the effect of migraine subtype on patient-reported outcome measures (PROM). Prior studies have characterized migraine in the general population. While this provides a basis for our understanding of migraine, we have less insight into the characteristics, comorbidities, and outcomes of migraine patients who present to subspecialty headache clinics. These patients represent a subset of the population that bears the greatest burden of migraine disability and are more representative of migraine patients who seek medical care. Valuable insights can be gained from a better understanding of CM and EM in this population. We conducted a retrospective observational cohort study of patients with CM or EM seen in the Cleveland Clinic Headache Center between January 2012 and June 2017. Demographics, clinical characteristics, and patient-reported outcome measures (3-Level European Quality of Life 5-Dimension [EQ-5D-3L], Headache Impact Test-6 [HIT-6], Patient Health Questionnaire-9 [PHQ-9]) were compared between groups. Eleven thousand thirty-seven patients who had 29,032 visits were included. More CM patients reported being on disability 517/3652 (14.2%) than EM patients 249/4881 (5.1%) and had significantly worse mean HIT-6 (67.3 ± 7.4 vs. 63.1 ± 7.4, p < 0.001) and median [interquartile range] EQ-5D-3L (0.77 [0.44-0.82] vs. 0.83 [0.77-1.00], p < 0.001), and PHQ-9 (10 [6-16] vs. 5 [2-10], p < 0.001). There are multiple differences in demographic characteristics and comorbid conditions between patients with CM and EM. After adjustment for these factors, CM patients had higher PHQ-9 scores, lower quality of life scores, greater disability, and greater work restrictions/unemployment.