Abstract
Objectives:
There are few epidemiological surveys that have examined risk factors longitudinally for age-related hearing impairment (ARHI). This study aims to identify risk factors that predict the development of age-related hearing impairment (ARHI), using survival analysis.
Methods:
This retrospective cohort study reviewed the records of the adult subjects (mean age = 55.6 years) who consecutively underwent health checkup including pure-tone audiometry at the Health Promotion Center in Samsung Medical Center between 2001 and 2010. In this period, a total of 2,577 subjects (2,148 males and 429 females) underwent pure-tone audiometry more than twice. A pure-tone average (PTA: 0.5, 1, 2, 4 kHz) was calculated for each subject, and development of ARHI was defined as a PTA at follow-up more than 5 dB greater than the baseline PTA. Kaplan-Meier and Cox regression analysis were used to examine the effects of various factors, including laboratory profiles, in the development of ARHI. Multivariable analysis was performed with the variables that are associated with the outcome in the univariable analysis.
Results:
Kaplan-Meier analysis reveals that ARHI occurs in 1,060 (41.1%) subjects at 6 years. Blood albumin (hazard ratio [HR] 0.341; confidence interval [CI] 0.245-0.474) and alpha-fetoprotein (HR 0.752; CI 0.705-0.802) levels are the most potent protective factors for the development of ARHI in Cox regression analysis. In contrast, total bilirubin (HR 1.232; CI 1.091-1.391) and glycated hemoglobin (HR 1.182; CI 1.092-1.280) are potential risk factors.
Conclusions:
Worsening of hearing over time is common in the adult population. Results highlight the protective role of blood albumin and alpha-fetoprotein levels in the development of ARHI.