Mediating Role of Oral Problems in the Link between Obstructive Sleep Apnea Risk and Hearing Difficulties: A Cross-sectional Study from the Korea National Health and Nutrition Examination Survey 2019-2023.

OBJECTIVE

This study examined the association between obstructive sleep apnea (OSA) risk and hearing difficulty and evaluated whether oral health problems mediate this relationship in a nationally representative Korean population.

METHODS

We analyzed 15,163 adults aged ≥40 years from the Korea National Health and Nutrition Examination Survey (KNHANES) 2019-2023 datasets. OSA risk was defined using the snoring, tiredness, observed apneas, pressure, body mass index, age, neck circumference, and gender (STOP-BANG) questionnaire (low risk: 0-2; high risk: ≥3). Oral health problems were operationalized as the summed score of self-reported chewing difficulty and speaking difficulty (two 5-point items; range 2-10). Hearing difficulty was assessed using the KNHANES 4-point self-reported hearing scale (1 = no difficulty to 4 = cannot hear at all). Mediation analyses were conducted using complex-sample hierarchical regression with design-weighted estimation, adjusting for survey year, age, sex, education, marital status, income, smoking, alcohol consumption, metabolic/cardiovascular disease comorbidities, occupational noise exposure, and tinnitus.

RESULTS

Adults with high-OSA risk had higher weighted mean hearing difficulty scores than the low-risk group (1.23 vs. 1.16). In the adjusted model, OSA risk was associated with hearing difficulty [total effect β = 0.031, 95% confidence interval (CI): 0.013-0.048, P < 0.001]. Oral problems were associated with OSA risk (β = 0.111, 95% CI: 0.049-0.174, P < 0.001) and hearing difficulty (β = 0.014, 95% CI: 0.000-0.027, p = 0.047). The indirect effect was statistically significant (β = 0.001, 95% CI: 0.001-0.002). The direct effect of OSA risk on hearing difficulty remained significant (β = 0.019, 95% CI: 0.011-0.047, P < 0.001).

CONCLUSIONS

The risk of OSA based on STOP-BANG was associated with increased hearing difficulty among Korean adults, and oral health problems statistically accounted for a small proportion of this cross-sectional association. These results highlight the potential value of jointly considering sleep-related symptoms, oral function, and hearing outcomes in population health research.