Context: Acupuncture has been found to be beneficial in the treatment of patients with knee osteoarthritis. However, response among such patients is highly variable. Identification of subjects with greater response would facilitate a more rational use of acupuncture.
Objective: To examine the relationship between demographic and psychosocial variables and response to acupuncture as defined by reduction in pain and disability at the end of an 8-week course of treatment.
Design: Retrospective study.
Setting: Outpatients attending rheumatologists or primary care physicians.
Patients: 37 patients with symptomatic knee osteoarthritis who had previously participated in a controlled trial using acupuncture were recalled for an interview approximately 1 year later.
Intervention: Structured interview, questionnaire completion, and an examination.
Main outcome measures: Depression, anxiety, helplessness, self-efficacy, and fatigue were measured by standard instruments. Knee examination and assessment of pain threshold were measured by dolorimetry.
Results: Response at 8 weeks was significantly related to duration of symptoms. A statistically nonsignificant trend was found for older and more educated subjects to have a better response; anxiety and fatigue were found to be inversely related to response (also statistically nonsignificant). Subjects with localized medial pain had significantly better response in terms of pain and disability than did subjects with generalized knee pain.
Conclusion: Other than a weak relationship with anxiety (at 8 weeks only), no evidence of a link between psychosocial variables and response to acupuncture was found. Prospective studies are needed to confirm these results.