Prevalence of familial cluster headache: a systematic review and meta-analysis
Emer O’Connor, Benjamin S. Simpson, Henry Houlden, Jana Vandrovcová, Manjit Matharu
Abstract
Abstract Introduction The population rate of familial cluster headache (CH) has been reported to be as high as 20% however this varies considerably across studies. To obtain a true estimate of family history in CH, we conducted a systematic review and meta-analysis of previously published data. Methods Our systematic review involved a search of electronic databases (Medline, EMBASE, PubMed, CINAHL) to identify and appraise studies of interest utilising the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. To further ameliorate the accuracy of our analysis we included an additional unpublished cohort of CH patients recruited at a tertiary referral centre for headache, who underwent detailed family history with diagnostic verification in relatives. Data was extracted and meta-analysis conducted to provide a true estimation of family history. Results In total, we identified 7 studies which fulfilled our inclusion criteria. The estimated true prevalence of CH patients with a positive family history was 6.27% (95% CI:4.65–8.40%) with an overall I 2 of 73%. Fitted models for gender subgroups showed higher estimates 9.26% (95% CI: 6.29–13.43%) in females. However the I 2 for the female model was 58.42% and significant ( p = 0.047). Conclusion Our findings estimate a rate of family history in CH to be approximately 6.27% (95% CI: 4.65–8.40%). While estimates were larger for female probands, we demonstrated high heterogeneity in this subgroup. These findings further support a genetic role in the aetiology of CH.