Comorbidity between and risk factors for severe hearing and memory impairment in older Americans

Comorbidities complicate our understanding of impairments and their risk factors. The objective of the current study was to assess the comorbidity between hearing impairment (HI) and memory impairment (MI) in older Americans and to assess to what extent they share common risk factors.

Data were examined from 5252 participants aged 65 years or older from the Third National Health and Nutrition Examination Survey (1988-1994).

The prevalence of HI and MI was 21.4 (SE 0.8)% and 8.3 (0.6)%, respectively, but the prevalence of concurrent impairment was only 2.1 (0.2)%. African Americans had higher odds of MI than whites (OR=3.75, 95% CI: 2.81, 5.00), but not of HI (OR=0.62, 95% CI: 0.42, 0.91). Leisure physical activity was associated with lower odds of MI, good lung function was associated with lower odds of HI, and moderate alcohol use was associated with lower odds of both HI and MI. Compared with individuals free of HI, the OR of MI was 1.07 (95% CI: 0.78, 1.47) for individuals with HI.

Although prevalence was relatively high, comorbidity was surprisingly low, and the two impairments were not significantly associated. In addition to age, other factors appear to play critical but different roles in the development of these impairments.