title: Caffeine and chronic back pain.
abstract: OBJECTIVE
  Tobacco use and other behavioral factors are associated with chronic back pain. Anecdotes suggest excess caffeine use may also be associated with chronic back pain. We compared caffeine consumption by chronic back pain patients with caffeine consumption by controls.
  
  
  METHODS
  Retrospective case-control study.
  
  
  METHODS
  A multispecialty outpatient facility.
  
  
  METHODS
  Sixty new, consecutive patients with chronic back pain compared to 60 new, consecutive patients without chronic back pain.
  
  
  METHODS
  Patients were prospectively asked to complete an intake questionnaire.
  
  
  METHODS
  Daily caffeine consumption was estimated by analyzing the intake questionnaire. Differences between groups were analyzed by both normal and nonparametric statistics.
  
  
  RESULTS
  Consumption of caffeine by patients with chronic back pain averaged 392.4 mg/day. Controls consumed 149.8 mg/ day, a significant difference (p = .0001). Men consumed 86% more caffeine per day than women (p = .02). Age and caffeine consumption showed little correlation (r = .126).
  
  
  CONCLUSIONS
  Patients with chronic back pain consume over twice as much caffeine as patients without chronic back pain. Confounding variables and possible mechanisms associating caffeine with chronic back pain are discussed.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Alternative, Medicine Research Institute and Teacher's Academy, Middlebury, VT 05753, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: McPartland
authors.forename: J A
authors.initials: JA
authors.lastname: Mitchell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001416:Back Pain / Q000139:chemically induced*; D002110:Caffeine / Q000008:administration & dosage / Q000009:adverse effects*; D016022:Case-Control Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D011795:Surveys and Questionnaires
chemical_list: D002110:Caffeine