Auditory function in 70- and 75-year-olds of four age cohorts. A cross-sectional and time-lag study of presbyacusis.

Within the framework of the gerontological and geriatric population studies in Göteborg, Sweden, 473 elderly persons were examined using pure-tone audiometry in two recent cohorts. The aim of this study was to present cross-sectionally acquired hearing data in these contemporary groups aged 70 and 75. Another objective was to compare hearing function at the same age over the last two decades (time-lag study) in three 70-year-old cohorts and three 75-year-old cohorts. The largest time-lags were 14 years (75-year-olds) and 21 years (70-year-olds). The most recently tested cohort of 70-year-olds, studied in 1992, demonstrated median pure-tone averages (PTA: 0.5, 1 and 2 kHz) of 20.2 dB HL in the left ear of men and 18.2 dB HL in women. The left median pure-tone thresholds at 4 kHz were 56.0 dB HL in men and 34.7 dB HL in women. Hearing acuity in 70-year-olds was not demonstrated to have changed in any consistent fashion over a 21-year time-lag. For the most recently evaluated 75-year-olds, the median PTA in the left ear was 27.3 dB HL in men and 21.6 dB in women. The left median 4 kHz threshold was 67.3 in the male group and 45.5 dB HL in the female group. Hearing in 75-year-olds over a time-lag of 14 years demonstrated somewhat better pure-tone thresholds predominantly in the men's better ear in the earliest cohort when compared to the cohort tested in 1990-91. However, there were no consistent differences of pure-tone thresholds between these age cohorts, except for the intermediate cohort 2, in which the men had generally worse hearing. Thus, there was no apparent evidence of changes of the auditory function in elderly of the same age over the last two decades. Gender-specific dissimilarities in annual pure-tone threshold deterioration between the ages of 70 and 75 were found and are discussed.