Childhood hearing impairment and its associated factors in sub-Saharan Africa in the 21st century: A systematic review and meta-analysis

BACKGROUND: Childhood hearing impairment is still a significant cause of disability in the 21st century in developing countries. Particularly, the burden is more severe in sub-Saharan Africa, where the majority of children with hearing problems is living. Thre are great variations and inconsistencies of available findings conducted in sub-Saharan Africa. Hence, the aim of this review was to determine the pooled prevalence of childhood hearing impairment and its associated factors in sub-Saharan Africa. METHODS: Studies were searched from main databases (PubMed, CINAHL, and African Journals Online), Google Scholar, and other relevant sources using electronic and manual techniques. All observational studies, written in English and conducted among participants (aged less than 18 years) from 2000 to 2018, were eligible. Heterogeneity between included studies was assessed using I(2), and publication bias was explored using visual inspection of the funnel plot. Statistical analysis was carried out to determine pooled prevalence using Stata version 14. In addition, subgroup analysis was carried out for the normality criteria of hearing thresholds and characteristics of the study populations. RESULTS: The pooled prevalence of hearing impairment was 10% (95% confidence interval (CI): 9%–11%). The magnitude of hearing impairment varies with the normality criterion used. The most commonly used threshold was 25 and 30 dB hearing level. The prevalence of hearing impairment based on normality criterion (>20 dB, >25 dB, >30 dB, and >35 dB) were 17%, 19%, 2%, and 1%, respectively. While in the questionnaire-based evaluation, the prevalence was 6% (95% CI: 3%–9%). In addition, based on population characteristics, the prevalence of hearing impairment for school or community-based children was 6% (95% CI: 5%–7%) while the prevalence for children with comorbidities was 23% (95% CI: 15%–31%). Chronic suppurative otitis media, impacted cerumen, advanced stage of human immunodeficiency virus, tuberculosis infection, and age of the children were associated with hearing impairment in sub-Saharan Africa. CONCLUSION: Hearing impairment in children and adolescents in sub-Saharan Africa was high, and associated with preventable and treatable risk factors.