Increasing Incidence of Facial Nerve Disorders in the United States from 2007 to 2022

Background: Incidence data on Facial Nerve Disorders (FND) and Bell's palsy are currently limited. Prior epidemiological studies have estimated the incidence rate of Bell's palsy to be between 11 and 53/100,000 individuals, although the most cited incidence data are from single regions or municipalities, many of which are outdated from several decades ago. Methods: This was a retrospective cohort study of US adults from 2007 to 2022 using the Merative (TM) Marketscan (R) Research Databases. Trends in the incidence of FND were described overall and by specific sociodemographic groups, including age, sex, region, and insurance plan type. Chi-squared and simple logistic regression analyses were performed. Results: From 2007 to 2022, the total adult incidence of all FND was 30.5/100,000, and the total incidence of Bell's palsy alone was 24.5/100,000. Over the study period, there was a significant annual increase of 2.1 cases of FND/100,000 adults (95% Confidence Interval [CI] 1.8, 2.3; p < 0.001), and a significant total increase of 1.5 cases of Bell's palsy/100,000 adults (95% CI 1.2, 1.7; p < 0.001). The total incidence of FND was higher in males (33.1/100,000) than in females (28.4/100,000, p < 0.001), and greater in older age groups (p < 0.001). Additionally, the incidence of FND varied significantly by region (p < 0.001) and insurance plan type (p < 0.001). Conclusions: This study provides up-to-date incidence rates for Bell's palsy and facial nerve disorders, based on national administrative claims data. Incidence rates of FND and Bell's palsy alone have been increasing in the United States from 2007 to 2022.