[Multifrequency attenuation patterns in age-related hearing loss: a longitudinal analysis using spline mixed-effects models].
Level 3 - non-randomized controlled study
Longitudinal observational cohort study analyzing repeat audiometry over time.
PubMed 41956765 · doi:10.3760/cma.j.cn115330-20250529-00299
What was done
The authors evaluated longitudinal pure-tone audiometry data from 111 patients (aged 50 years or older at baseline; followed between January 2009 and May 2025) at a single hospital in China who completed at least two hearing tests separated by at least 1 year. Patients with symmetrical hearing and no history of high noise exposure, otitis media, or sudden deafness were included. Natural spline mixed-effects models were constructed to analyze nonlinear threshold shifts, age effect coefficients (beta), and annual progression rates across individual frequencies.
What was found
Mean baseline age was 72.9 ± 9.9 years, with 2 to 17 follow-up visits over a mean test interval of 7.2 ± 4.3 years (maximum 14.9 years). Hearing thresholds increased nonlinearly across all frequencies (P < 0.001). High frequencies showed higher age effect coefficients than low frequencies (8,000 Hz basis function B2: beta = 72.21, t = 7.46 vs. 500 Hz basis function B3: beta = 39.12, t = 9.95). The pure-tone average (PTA; mean of 500, 1,000, 2,000, 4,000 Hz) basis function B2 coefficient (beta = 46.97) was lower than the full-frequency mean (beta = 51.24) and synchronized with 2,000 Hz. The 8,000 Hz frequency had the highest annual increase rate (1.10 dB/year), peaking at 70-74 years (1.39 dB/year) and declining to 0.56 dB/year at 90-100 years. The 125 Hz rate increased steadily from 0 dB/year at 50-54 years to 1.04 dB/year at 80-84 years.
Why it matters
The findings characterize a multi-stage, nonlinear trajectory of age-related hearing deterioration across frequencies and suggest that hearing thresholds at 2,000 Hz may serve as an effective screening indicator for overall pure-tone average decline.
Limits
The sample size is modest (111 patients) and collected from a single department. The cohort has a severe sex imbalance (104 men and 7 women), limiting generalizability. Follow-up frequency varied widely (2 to 17 tests), and potential confounding medical or lifestyle factors were not reported.
Cited by
- supports Humans tend to lose high-frequency hearing before they lose low-frequency hearing.