title: Effect of weather on back pain: results from a case-crossover study.
abstract: OBJECTIVE
  To investigate the influence of various weather conditions on risk of low back pain.
  
  
  METHODS
  We conducted a case-crossover study in primary care clinics in Sydney, Australia. A total of 993 consecutive patients with a sudden, acute episode of back pain were recruited from October 2011 to November 2012. Following the pain onset, demographic and clinical data about the back pain episode were obtained for each participant during an interview. Weather parameters (temperature, relative humidity, air pressure, wind speed, wind gust, wind direction, and precipitation) were obtained from the Australian Bureau of Meteorology for the entire study period. Weather exposures in the case window (time when participants first noticed their back pain) were compared to exposures in 2 control time windows (same time duration, 1 week and 1 month before the case window).
  
  
  RESULTS
  Temperature, relative humidity, air pressure, wind direction, and precipitation showed no association with onset of back pain. Higher wind speed (odds ratio [OR] 1.17 [95% confidence interval (95% CI) 1.04-1.32], P = 0.01 for an increase of 11 km/hour) and wind gust (OR 1.14 [95% CI 1.02-1.28], P = 0.02 for an increase of 14 km/hour) increased the odds of pain onset.
  
  
  CONCLUSIONS
  Weather parameters that have been linked to musculoskeletal pain such as temperature, relative humidity, air pressure, and precipitation do not increase the risk of a low back pain episode. Higher wind speed and wind gust speed provided a small increase in risk of back pain, and although this reached statistical significance, the magnitude of the increase was not clinically important.
authors.affiliation: The George Institute for Global Health, Sydney Medical School, and The University of Sydney, Sydney, New South Wales, Australia; Federal University of Minas Gerais, Minas Gerais, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Steffens
authors.forename: Chris G
authors.initials: CG
authors.lastname: Maher
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.forename: Manuela L
authors.initials: ML
authors.lastname: Ferreira
authors.forename: Leani S M
authors.initials: LS
authors.lastname: Pereira
authors.forename: Bart W
authors.initials: BW
authors.lastname: Koes
authors.forename: Jane
authors.initials: J
authors.lastname: Latimer
mesh_terms: D000328:Adult; D001315:Australia; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D006813:Humidity; D017116:Low Back Pain / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012306:Risk; D012621:Seasons; D013696:Temperature; D014887:Weather; D014919:Wind