• Bell's palsy;
  • Parkinson's disease;
  • case-control study;
  • risk factors


We investigated the association of Bell's palsy (BP) with the subsequent risk of Parkinson's disease (PD) using a case-control study design. We matched 196 incident cases of PD in Olmsted County, MN, to 196 general population controls with same age (±1 year) and sex, and we reviewed the complete medical records of cases and controls in a medical records-linkage system to detect BP. Six of the 196 patients with PD and none of the 196 controls were diagnosed with BP before PD (exact binomial probability, P = 0.02). The median age at occurrence of BP was 49.5 years (range, 15–84 years) and the median time between BP and the onset of PD was 27.5 years (range, 2–54 years). The findings were similar using a standardized incidence ratio (SIR) approach, but were not statistically significant. This initial association between BP and PD awaits replication. © 2009 Movement Disorder Society