A case-control study examining the role of physical trauma in the onset of rheumatoid arthritis

Abstract

Objective. To investigate whether physical trauma may precipitate the onset of rheumatoid arthritis (RA). Method. In a case-control study comparing RA out-patients with controls attending non-rheumatology out-patient clinics, 262 patients and 262 age- and sex-matched controls completed a postal questionnaire or were interviewed about any physical trauma in the 6 months before the onset of their symptoms. Results. Fifty-five (21%) of the RA patients reported significant physical trauma in the 6 months before the onset of their disease, compared with only 17 (6.5%) of the controls (P<0.00001). A preceding history of physical trauma was significantly more common in RA patients who were seronegative for rheumatoid factor (P = 0.03), but was not significantly associated with sex (P = 0.78), age (P = 0.64), a family history of RA (P = 0.07) or type of occupation, defined as manual or sedentary (P = 0.6). Conclusion. Physical trauma in the preceding 6 months is significantly associated with the onset of RA.