The incidence and recovery rate of idiopathic vocal fold paralysis: a population-based study.

PURPOSE: To determine the incidence and spontaneous recovery rate of idiopathic vocal fold paralysis (IVFP) and paresis (IVFp), and the impact of steroid treatment on rates of recovery. METHODS: This retrospective cohort study included all patients with IVFP or IVFp within a large integrated health-care system between January 1, 2008 and December 31, 2014. Patient demographics and clinical characteristics, including time to diagnosis, spontaneous recovery status, time to recovery, and treatment, were examined. RESULTS: A total of 264 patients were identified, 183 (69.3%) with IVFP and 81 (30.7%) with IVFp. Nearly all cases (96.6%) were unilateral and 89.8% of patients were over the age of 45. The combined (IVFP and IVFp) 7-year mean incidence was 1.04 cases per 100,000 persons each year with the highest 7-year mean annual incidence in white patients (1.60 per 100,000). The total rate of spontaneous recovery was 29.5%, where 21.2% had endoscopic evidence of resolution and 8.3% had clinical improvement in their voice without endoscopic confirmation. The median time to symptom resolution was 4.0 months. Use of steroids was not linked with spontaneous recovery in multivariable analyses. CONCLUSION: The annual incidence of VFP (IVFP and IVFp) was 1.04 cases per 100,000 persons, with spontaneous recovery occurring in nearly a third of patients, regardless of steroid use.