Clinical characteristics of medication-overuse headache according to the class of acute medication: A cross-sectional multicenter study

Objective: To characterize the clinical features of patients with medication-overuse headache (MOH) according to the class of acute medications being overused. Background: MOH is a common global health problem, severely disabling the majority of the patients affected. Although various medications can cause MOH, whether clinical features differ according to the overused medication type remains unclear. Methods: We analyzed data from a multicenter cross-sectional study in neurology clinics in Korea from April 2020 to June 2021. Results: Among 229 eligible patients, MOH was documented in patients who overused multiple drug classes (69/229, 30.1%; most frequent occurrence), triptans (50/229, 21.8%), non-opioid analgesics (48/229, 21.0%), and combination-analgesics (40/229, 17.4%). Patients who overused multiple drug classes reported more frequent use of acute medications (median [25th–75th percentiles]: 25.0 [15.0–30.0] vs. 17.5 [10.0–25.5] days/month, p = 0.029) and fewer crystal-clear days (0.0 [0.0–9.5] vs. 9.0 [0.0–10.0] days/month, p = 0.048) than those who overused triptans. Patients who overused multiple drug classes also reported shorter intervals from chronic daily headache to the onset of MOH than patients who overused combination-analgesics (0.6 [0.2–1.9] vs. 2.4 [0.7–5.4] years, p = 0.001) or non-opioid analgesics (1.5 [0.6–4.3] years, p = 0.004). Patients who overused multiple drug classes reported more emergency room visits (1.0 [0.0–1.0] visits/year) than those who overused combination-analgesics (0.0 [0.0–1.0], p = 0.024) or non-opioid analgesics (0.0 [0.0–1.0], p = 0.030). Patients who overused triptans reported fewer headache days (21.0 [20.0–30.0] vs. 30.0 [20.5–30.0] days/month, p = 0.008) and fewer severe headache days (7.0 [4.0–10.0] vs. 10.0 [5.0–15.0] days/month, p = 0.017) than those who overused non-opioid analgesics. Conclusions: Some clinical characteristics of MOH significantly differed according to the class of overused medications. The findings from this study may contribute to the understanding of the clinical characteristics and pathophysiology of MOH.