Longitudinal changes in hearing sensitivity among men: the Veterans Affairs Normative Aging Study.

Over 35 years (1962-1996), participants of the Veterans Affairs Normative Aging Study (NAS), a study of healthy aging in men, completed up to eight audiometric assessments. This report describes the age-related hearing trajectories of screened men (n=953) aged 23 to 81 years at enrollment, estimates the typical rate of change per decade in hearing sensitivity, and compares longitudinal and cross-sectional estimates of change in hearing sensitivity. The men were followed 14 years on average. The hearing trajectories, based on a mixed-effects model analytical approach to the data, provide converging evidence that hearing loss in aging is pervasive and progressive even among men initially selected for good physical health. Typically the men accrued early losses (>25 dB HL) in hearing sensitivity at the higher frequencies beginning in the early 40s, but maintained hearing thresholds better than 25 dB HL for lower frequencies into old age. The average rate of change per year across frequencies and age was 0.69 dB. Predicted cross-sectional estimates of change in hearing sensitivity reliably approximated longitudinal trajectories, with slight misestimations in the 8th decade.