Burden of hearing loss and diagnostic utility of a screening tool in Kazakhstan: insights from national and cross-sectional analyses

Background: Hearing loss is a significant public health concern that is often under recognized globally, with mild impairment accounting for the largest share of the burden. In Kazakhstan, little is known about national patterns of hearing loss or the utility of simple screening tools for detecting it. This study assessed the burden of hearing loss via Global Burden of Disease (GBD) data and evaluated the diagnostic performance of the Hearing Handicap Inventory for Adults-Screening version (HHIA-S) relative to audiometric testing. Methods: We analyzed GBD 2021 data to estimate the prevalence and years lived with disability (YLDs) from 1990 to 2021. Additionally, a cross-sectional survey was conducted among 506 adults recruited from primary healthcare facilities in Astana and nearby areas. All participants completed the HHIA-S questionnaire and underwent audiometric testing. Diagnostic accuracy was assessed via sensitivity, specificity, predictive values, and the area under the ROC curve (AUC). Results: In 2021, the age-standardized prevalence of hearing loss in Kazakhstan was 17,212 per 100,000 population (95% UI: 16,469-18,048), with mild hearing loss accounting for 71.9% of the cases. The YLD rate was 512 per 100,000 (95% UI: 346 s-732), showing stable trends since 1990. In the cross-sectional study, 20% of the participants had audiometrically confirmed hearing loss, with the prevalence rising sharply after the age of 60 years. Women composed 74% of the sample. The HHIA-S demonstrated a sensitivity of 70.2%, a specificity of 94.1%, a positive predictive value of 77.7%, a negative predictive value of 91.6%, and an AUC of 0.82, indicating good diagnostic performance. Conclusion: Hearing loss remains an important but under recognized health problem in Kazakhstan. Integrating simple screening tools such as the HHIA-S into primary care alongside strengthened audiological services and public awareness campaigns could facilitate early detection and reduce the long-term burden of untreated hearing impairment.