The Prevalence and Related Factors of Hearing Loss Among Adults: A Systematic Review and Meta-Analyses

Objectives: We aimed to estimate the global prevalence of hearing loss among adults and to explore its associated factors. Methods: Our systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement (PRISMA). We retrieved corresponding documents published up to Sep 24, 2021 in PubMed and Web of Science. Random-effects models were used to calculate the pooled prevalence of hearing loss. Subgroup analyses were conducted to explore potential heterogeneity. Results: The pooled prevalence of any hearing loss across 100 studies was 31.0% (95% CI: 26.9-35.1, P < .001, I 2 = 99.9%), and the pooled prevalence of disabling hearing loss across 34 studies was 15.9% (95% CI: 11.1-20.7, P < .001, I 2 = 99.9%). The prevalence of hearing loss was higher in the year range of 2000 to 2009, among the elder (≥70) or males, in studies using either ear side of hearing loss definition or in the region of the Americas. Ear disease or surgery, job noise exposure, current smoking, off-work noise exposure, males, cardiovascular disease, past drinking, diabetes mellitus, hypertension, older age, and past smoking are risk factors of hearing loss while education level surpasses high school acts as a protect factor for hearing. Conclusion: Our results demonstrate high prevalence of hearing loss among adults worldwide and verify several related factors of the disease. Prevention and intervention measures should be implemented.