Clinical reference · Card 07 of 11 · Epidemiology
The sex ratio — a moving number and a diagnostic trap
Cluster headache is male-predominant, but the ratio has fallen steadily and contemporary cohorts disagree. Treat it as a weak prior, never a rule-out.
M:F BY DECADE OF SYMPTOM ONSET · MANZONI 1998, N=482
CONTEMPORARY COHORTS — STILL NO CONSENSUS
Sweden 2023 n=8741.9 : 1
Denmark 2017 n=3512.0 : 1
Belgium 2026 1979–20245.3 → 2.6 : 1
China 2026 n=1,2063.9 : 1
Taiwan 2022 n=7985.2 → 4.3 : 1
Meta-analysis 2026 19 studies4.9 : 1 pooled
The ratio inverts with age at onset · Ekbom 2002, n=554A woman over 50 with new side-locked attacks and autonomic features is the classic missed case, not an unlikely one.
ONSET AT 30–49
7.2:1episodic11.0:1chronic
Heavily male.ONSET AFTER 50
2.3:1episodic0.6:1chronic
Female-predominant.WHY THE NUMBER IS UNRELIABLE — AND WHAT IT DOES TO WOMENWomen are misdiagnosed more often than men — 61.1% vs 45.5% — and far more often need a tertiary centre to get the diagnosis (38.8% vs 20.9%; Denmark, n=351). Women more often have comorbid migraine (pooled OR 2.72; 28.3% vs 15.9%), and migraine-like features are an established driver of delay. If women are labelled migraineurs they never enter the cluster headache denominator — plausibly inflating the ratio itself.Counterweight: a 2025 meta-analysis (n=8,654) found female sex was NOT an independent predictor of delay — migraine-like features were. Sex is a proxy, not the mechanism.
For practice: do not use male sex as supporting evidence, or female sex as evidence against. Published ratios come from headache clinics, not populations, and are shaped by who gets referred.
SOURCES Manzoni GC. Cephalalgia 1998;18:138–42. Ekbom K et al. Cephalalgia 2002;22:94–100. Lund N et al. Neurology 2017;88:1069–76. Fourier C et al. Neurology 2023;100:e1207–20. Liaw YC et al. Cephalalgia 2022;42:1532–42. CHRIS, J Headache Pain 2026; Acta Neurol Belg 2026.
Cluster headache tracking and analysis for patientsmyclusters.nlGet the printed setAll 11 cards, A6, printed back to back. The print-ready PDF unlocks when you request.