Subclinical Hearing Loss is Associated With Depressive Symptoms.

Objective: To assess whether the relationship between hearing and depressive symptoms is present among older adults classified as normal hearing (≤25 dB).

Design: Cross-sectional epidemiologic study (Hispanic Community Health Study).

Setting: US multicentered.

Participants: Adults ≥50 years old (n = 5,499) with normal hearing or hearing loss (HL).

Measurements: The primary exposure was hearing, defined continuously by the 4-frequency pure-tone average threshold (dB) on audiometry. Hearing was additionally categorized into normal hearing (≤25 dB) and HL (>25 dB). The main outcome was depressive symptoms, measured with the Center for Epidemiologic Studies Depression Scale-10 (CESD-10). Depressive symptoms were defined both continuously and binarily (where CESD-10 ≥10 was categorized as clinically significant depressive symptoms). Multivariable linear, logistic, and generalized additive modeling (GAM) regressions were performed.

Results: Among those with normal hearing, the CESD-10 score increased by 1.04 points (95% confidence interval [CI]: 0.70, 1.37) for every 10 dB decrease in hearing, adjusting for age, gender, education, cardiovascular disease, and hearing aid use. Among those with HL, the CESD-10 score increased by 0.62 points (95% CI: 0.23, 1.01) for every 10 dB decrease in hearing, adjusting for the same confounders. Similar findings were noted when the outcome was clinically significant depressive symptoms (adjusted odds ratio: 1.28 [1.14, 1.44] in normal hearing versus 1.26 [1.11, 1.44] in HL). In certain sensitivity analyses, the relationship between hearing and depressive symptoms was significantly stronger among those with normal hearing than in those with HL.

Conclusion: The relationship between hearing and clinically significant depressive symptoms is present among older adults with normal hearing (<25 dB). We introduce the term subclinical HL as imperfect hearing that is classically defined as normal (1-25 dB). The relationship between hearing and late life depressive symptoms may be more sensitive than previously recognized.