Sex-Specific Associations Between Diabetes Mellitus and Hearing Loss in the Middle-Aged and Elderly Individuals: A National Cohort Study of Chinese Adults

To examine the association between diabetes and hearing loss and whether the association varied by sex.This cohort study based on nationally representative data from the China Health and Retirement Longitudinal Study included 16 140 Chinese adults aged >45 years between 2011 and 2018. Diabetes was identified by blood glucose levels, HbA1c levels, and a self-reported diagnosis at baseline. The main outcome was self-reported incident hearing loss. Cox proportional hazards regression models were performed to estimate the risk of hearing loss.We documented 2388 cases of hearing loss during a median 6.9 years of follow-up. The incidence rates were 29.64 (95% CI, 28.07-31.29) per 1000 person-years in women and 25.23 (95% CI, 23.77-26.78) per 1000 person-years in men. After adjustment, the hazard ratios of hearing loss associated with diabetes were 1.20 (95% CI, 1.01-1.42) for women and 0.97 (95% CI, 0.78-1.19) for men. Compared with poor control of the blood sugar levels, the odds ratio for hearing loss for women with good glycemic control was reduced from 5.08 (95% CI, 1.31-19.66) to 1.26 (95% CI, 0.69-2.28), and the corresponding odds ratio for men was 1.65 (95% CI, 0.61-4.44) to 0.50 (95% CI, 0.18-1.38).In conclusion, we identified a differential effect of sex on hearing loss risk with more pronounced effects for women. Our data suggest that good blood glucose level control is helpful to prevent hearing loss.