title: Effects of Wind Chill Factor, Temperature and Other Meteorological Parameters on the Incidence of Bell's Palsy: Results Based on a Retrospective, 7-Year Long, Greek Population Study.
abstract: BACKGROUND
  The etiology of Bell's palsy (BP), the most common type of dysfunction of the facial nerve, remains unclear despite vigorous research. Data concerning the effects of meteorological factors (MFs) on its appearance are inconclusive. The aim of our study was to examine the demographics of a convenience sample of patients with BP and to determine the effects of several MFs in the recorded number of cases per month (cpm).
  
  
  METHODS
  We retrospectively reviewed 568 files of BP patients and concomitant data of MFs during an 84-month observation period. Information collected included age, gender, diabetic status, number of cpm (months further categorized as winter or summer), mean daily and monthly temperatures and wind speeds and monthly values of wind chill factor (WCF), a measure dependent on both temperature and wind speed. Potential correlations were estimated by univariate analyses (p = 0.05).
  
  
  RESULTS
  Demographics were in line with previous research regarding age and diabetic status, but indicative of slight male preponderance. Summer months and mean monthly temperatures showed significant negative correlations with cpm (p = 0.002 and <0.000, respectively) and strong positive correlation with WCF (p < 0.000).
  
  
  CONCLUSIONS
  MFs can substantially influence the possibility for BP appearance. We propose WCF as a novel, reliable estimator of the overall MF-derived risk.
authors.affiliation: 1st Department of Neurology, Medical School of National and Kapodistrian University of Athens, Aeginition Hospital, Athens, Greece.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kokotis
authors.forename: Serafeim
authors.initials: S
authors.lastname: Katsavos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020330:Bell Palsy / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D006115:Greece / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008685:Meteorological Concepts; D008875:Middle Aged; D012189:Retrospective Studies; D013696:Temperature; D014919:Wind; D055815:Young Adult