Association of sudden sensorineural hearing loss with asthma: a longitudinal follow-up study using a national sample cohort

OBJECTIVE: To investigate the risk of sudden sensorineural hearing loss (SSNHL) in asthma patients. DESIGN: A longitudinal follow-up study using a retrospective cohort SETTING: The 2002–2013 Korean National Health Insurance Service-Health Screening Cohort PARTICIPANTS AND INTERVENTIONS: The ≥40 years old Korean population were enrolled. The asthma patients were 1:1 matched with the control group for age, sex, income and region of residence. MAIN OUTCOME MEASURE: The occurrence of SSNHL was followed in both asthma and control groups. The stratified Cox proportional hazard model was used. Age, sex, income and region of residence were stratified, and Charlson Comorbidity Index scores, obesity, smoking, alcohol consumption and atopic dermatitis histories were adjusted. Subgroup analysis was performed according to age, sex, obesity, smoking and alcohol consumption. RESULTS: The results showed that 1.0% (877/90 564) of the asthma group and 0.8% (706/90,564) of the control group exhibited SSNHL (p<0.001). The asthma group demonstrated a higher HR for SSNHL than the control group (adjusted HR 1.23, 95% CI 1.11 to 1.36, p<0.001). According to age and sex, the female subgroup showed elevated HRs for SSNHL in asthma patients. Both the non-smoker and current smoker groups demonstrated higher HRs for SSNHL in asthma patients than in controls. According to alcohol consumption or obesity, the <1 time a week alcohol consumption group and normal weight and severe obesity groups showed higher HRs for SSNHL in asthma patients than in the controls. CONCLUSIONS: Adult asthma patients had a higher risk of SSNHL than the control participants matched for demographic and socioeconomic factors.