Lower bioelectrical phase angle is associated with audiometric hearing loss in middle-aged and older adults

Bioelectrical phase angle is an integrated marker of cellular integrity, fluid distribution, nutritional status, and physiological reserve, but its relationship with objective sensory function in later life remains unclear. This population-based cross-sectional study analyzed adults aged 40 years or older from the 2022-2023 Korea National Health and Nutrition Examination Survey. Whole-body phase angle at 50 kHz was assessed using bioelectrical impedance analysis, and pure-tone audiometry was used to determine better-ear speech-frequency pure-tone average (PTA) and high-frequency hearing thresholds. Survey-weighted linear and logistic regression analyses were conducted after adjustment for age, sex, body mass index, hypertension, diabetes, current smoking, and alcohol ever use. Among 5,436 participants, each 1-degree increase in phase angle was associated with a 1.50-decibel lower better-ear PTA (95% confidence interval [CI], - 1.97 to - 1.02; P < 0.001) and a 1.51-decibel lower better-ear high-frequency threshold (95% CI, - 2.33 to - 0.69; P < 0.001), indicating lower, better hearing thresholds. Higher phase angle was also associated with reduced odds of audiometric hearing loss, defined as better-ear PTA ≥ 25 decibels hearing level (odds ratio, 0.79; 95% CI, 0.68 to 0.92; P = 0.002). Exploratory age-stratified analyses showed that these associations were evident among adults aged 40 years or older but not among participants aged 12-39 years. These findings support further evaluation of bioelectrical phase angle as a complementary research marker linking objective sensory function with systemic reserve in middle-aged and older adults; longitudinal validation is required before any screening application.