Association of sudden sensorineural hearing loss with increased risk of insomnia: a nationwide population-based cohort study

Study Objectives: To evaluate the risk of insomnia in patients with sudden sensorineural hearing loss (SSNHL). Methods: A retrospective propensity score–matched cohort study was conducted using a nationwide representative sample from the National Sample Cohort 2002–2013 data from the Korea National Health Insurance Service. The SSNHL group (n = 631) included patients diagnosed with SSNHL between January 2002 and December 2005. The comparison group (4 controls for every patient with SSNHL, n = 2,524) was selected using propensity score matching, according to sociodemographic factors and the year of enrollment. Each patient was monitored until 2013. Survival analysis, log-rank test, and Cox proportional hazards regression models were used to calculate the incidence, survival rate, and hazard ratio (HR) of insomnia for each group. Results: Among the 3,155 individuals included in the study population (male, 48.6%), the overall incidence of insomnia during the 11-year follow-up was 1.4-fold higher in the SSNHL group than in the non-SSNHL group (106.3 vs 138.3 per 10,000 person-years; adjusted HR, 1.38; 95% confidence interval [CI], 1.08–1.78). Moreover, the adjusted HRs for developing insomnia (depression, 3.33 [95% CI, 2.22–5.01]; anxiety, 1.78 [95% CI, 1.27–2.53]; tinnitus, 1.56 [95% CI, 1.2–2.03]; dizziness, 1.76 [95% CI, 1.27–2.44]) were higher in patients with comorbidities. Conclusions: This observational study suggests that SSNHL is associated with an increased incidence of insomnia. Specifically, findings from this study show that patients with tinnitus, depression, anxiety, and dizziness had a higher risk of developing insomnia than those without tinnitus, depression, anxiety, and dizziness.