Epidemiology of Digital Clubbing and Hypertrophic Osteoarthropathy: A Systematic Review and Meta-analysis.

Digital clubbing and hypertrophic osteoarthropathy (HOA) are long-standing clinical entities, but their prevalence have not been synthesized. We aimed to estimate the prevalence of digital clubbing and HOA in people with existing medical conditions.We comprehensively searched PubMed, Embase, and Web of Science to select studies addressing HOA or digital clubbing and published through March 23, 2021. Summary estimates of the prevalence were derived through random-effects meta-analysis and narrative synthesis. The review protocol has been registered with PROSPERO, CRD42021243934.Of 3973 records, we included 142 studies. In adults, the pooled prevalence of digital clubbing was 33.4% (95% confidence interval [CI], 16.6-52.8), 31.3% (95% CI, 22.4-41.1), 27% (95% CI, 9.4-49.5), and 22.8% (95% CI, 10.8-37.6) in subjects with intestinal diseases, interstitial lung diseases, infective endocarditis, and hepatic diseases, respectively. In children and adolescents, the pooled prevalence of digital clubbing was 29.1% (95% CI, 19.4-39.9), 23% (95% CI, 9.0-41.1), 19.5% (95% CI, 4.1-42.4), and 17.1% (95% CI, 9.5-26.5) in subjects with human immunodeficiency virus infection, hemoglobinopathies, cystic fibrosis, and tuberculosis. The pooled prevalence of HOA was 10.1% (95% CI, 2.0-23.1) in adults with cancers, and 5% (95% CI, 2.5-8.2) in children and adolescents with cystic fibrosis.In conclusion, the prevalence of digital clubbing varied across disease groups in both adults and children. Full-spectrum HOA was mostly reported in adults with liver disease and cancers, and in children and adolescents with cystic fibrosis.