Association between Metabolic Syndrome and Risk of Hearing Loss: a Systematic Review and Meta-analysis

Introduction: Various studies have linked lifestyle and metabolic diseases to hearing loss. Research on metabolic syndrome has reported a higher prevalence of hearing loss in individuals with it than those without it. Objectives: To conduct a systematic review and meta-analysis summarizing the risk of hearing loss in people diagnosed with metabolic syndrome or diseases versus those without metabolic syndrome. Methods. Following the PRISMA recommendations for systematic review and meta-analysis, searches were conducted in PubMed, Web of Science, and SciELO. Only cross-sectional studies associate hearing loss with obesity, hypertension, Diabetes, Dyslipidemia, Cholesterol, metabolic syndrome, and Hyperglycemia. The odds ratios (OR) with their 95% confidence intervals (CI) of the studies were pooled in a random effects model using the Mantel-Haenszel method. Using Rev Manager 5.1, OR heterogeneity was assessed using the I2 and Q statistics. Results. Twenty-eight observational studies were included in the quantitative analysis. The OR for prevalent hearing loss was 1.27 (95% CI 1.07, 1.51) in obesity, 1.97 (95% CI 1.51, 2.57) in diabetes, 1.53 (95% CI 1.31, 1.79) in hypertension, and 4.22 (95% CI 1.74, 10.20) for metabolic syndrome. Conclusions. The findings suggest that both metabolic syndrome and some diseases, such as obesity, diabetes, and hypertension, could be associated with the risk of hearing loss, and control of these diseases could reduce this risk.