Associations between dietary indices and hearing status among middle-older aged adults - results from the Baltimore Longitudinal Study of Aging

Background: Hearing loss, a public health issue in older populations, is closely related to functional decline. Objective: To investigate the longitudinal associations between 4 dietary indices and hearing status. Methods: Data from the Baltimore Longitudinal Study of Aging were used and included 882 participants >= 45 y of age. Dietary intake was assessed using a validated food frequency questionnaire, and 4 dietary scores (Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay diet [MIND], Mediterranean style diet score [MDS], Alternative Healthy Eating Index [AHEI], and Healthy Eating Index [HEI]) were calculated as averages over time. Hearing status was examined using pure -tone audiometry, and pure -tone average (PTA) of hearing thresholds were calculated at speech-level (PTA (500, 1000, 2000, 4000 Hz) ), low (PTA (500, 1000 Hz) ), and high (PTA (4000, 8000 Hz) ) frequencies, with lower thresholds indicating better hearing. Multivariable linear mixed-effect models were used to examine associations between dietary indices and hearing threshold change over time adjusted for confounders. Results: At baseline, the mean age of participants was 67 y and 55% were female. Over a median of 8 y of follow-up, MDS >= 7 was associated with 3.5 (95% CI: - 6.5, - 0.4) and 5.0 (95% CI: - 9.1, - 1.0) dB lower PTA (500, 1000, 2000, 4000 Hz) and PTA (4000, 8000 Hz) , respectively, compared with MDS <= 3; the highest tertile of the AHEI was associated with 2.3 (95% CI: - 4.6, - 0.1) and 5.0 (95% CI: - 8.0, - 2.0) dB lower PTA (500, 1000, 2000, 4000 Hz) and PTA (4000, 8000 Hz) ; and each standard deviation increment in HEI was associated with 1.6 dB (95% CI: - 2.7, - 0.6), 1.1 dB (95% CI: - 2.1, - 0.1), and 2.1 dB (95% CI: - 3.5, - 0.6) lower PTA (500, 1000, 2000, 4000 Hz) , PTA (500, 1000 Hz) , and PTA (4000, 8000 Hz) , respectively. Conclusions: Adherence to healthy dietary patterns was associated with better hearing status, with stronger associations at high frequencies. Am J Clin Nutr 20xx;x:xx.