Sixteen-year change in acoustic-admittance measures among older adults: data from a population-based study

The primary purpose of this study was to measure the 16-year change in peak compensated static acoustic admittance (Peak Y(tm)) in a population-based cohort of older adults, and to determine whether age was associated with any observed change in Peak Y(tm). Other tympanometric measures also were taken and analyzed.

Data from two examinations (1993-1995 and 2009-2010) of the population-based Epidemiology of Hearing Loss Study (n = 1,439 with data at both examinations, ages 48-84 years at baseline) were utilized to assess 16-year change. Tympanometric measures were taken using a 226-Hz probe tone, a positive-to-negative direction of pressure change, and a measured pump speed of 600/200 daPa/s.

During the 16-year period, Peak Y(tm) declined an average of 0.009 mmho/year (0.009/year for women, 0.007/year for men). Among women, older baseline age was associated with greater decline in Peak Y(tm). Among men, baseline age was associated with change in Peak Y(tm), but in a nonlinear pattern. Other tympanometric measures demonstrated little change after 16 years.

These results demonstrate a small degree of middle-ear stiffening after 16 years among these older adults, but not enough to affect function in a manner that would influence clinical decisions.