Hearing Impairment Increases Economic Inequality

Objectives. We evaluated changes in income levels in a hearing-impaired population. Methods. The study subjects were selected from the Korean National Health Insurance Service-Health Screening Cohort data from 2002 to 2015 of Koreans >= 40 years old. In total, 5,857 hearing-impaired subjects were matched with 23,428 comparison participants. Differences between the initial income level and income levels at 1, 2, 3, 4, and 5 years post-enrollment were compared between the hearing-impaired and comparison groups. The interaction of time and hearing impairment/comparison was estimated. Results. Both the hearing-impaired group and the comparison group showed increased income levels over time. In the hearing-impaired group, the income levels at 4 and 5 years post-enrollment were higher than the initial income level (each P<0.001). In the comparison group, the income levels of all the participants after 1-5 years were higher than the initial income level (each P<0.001). The interaction of time and hearing impairment was statistically significant (P= 0.021). Conclusion. The increase in income over time was relatively lower in the hearing-impaired adult population; therefore, the income gap widened between this population and the normal-hearing population.