Three decade change in the prevalence of hearing impairment and its association with diabetes in the United States.

OBJECTIVE To examine the secular change of the prevalence of hearing impairment over three decades in U.S. adults with and without diabetes. METHODS The cross-sectional National Health and Nutrition Examination Surveys (NHANES, the 1971-1973 [NHANES I] and the 1999-2004 [NHANES 1999-2004]) were used. Average pure-tone audiometry thresholds in decibels (dB) at 1, 2, 3, and 4 kHz frequencies of the worse ear were used to represent the participants' hearing status. Any hearing impairment was defined as average pure-tone audiometry threshold of the worse ear >25 dB. RESULTS From 1971 to 2004, among adults without diabetes aged 25 to 69 years, the unadjusted prevalence of hearing impairment decreased from 27.9% to 19.1% (P<0.001), but among adults with diabetes there was no significant change (46.4% to 48.5%). After adjustment for age, sex, race, and education, the prevalence of hearing impairment in the NHANES I and NHANES 1999-2004, respectively, was 24.4% (95% confidence interval [CI], 22.3-26.6%) and 22.3% (95% CI, 20.4-24.2) for adults without diabetes and 28.5% (95% CI, 20.4-36.6%) and 34.4 (95% CI, 29.1-39.7%) for adults with diabetes. The adjusted prevalence ratios of hearing impairment for persons with diabetes vs. those without diabetes was 1.17 (95% CI, 0.87-1.57) for the NHANES I and 1.53 (95% CI, 1.28-1.83) for NHANES 1999-2004. CONCLUSIONS Persons with diabetes have a higher prevalence of hearing impairment, and they have not achieved the same reductions in hearing impairment over time as have persons without diabetes.