Impact of Preoperative Mental Health Status on Functional Outcome 1 Year after Total Hip Arthroplasty

Background: The aim of this prospective cohort study was to determine the effect of preoperative mental health status on functional outcome 1 year after total hip arthroplasty (THA). Methods: Data were collected for 677 patients from a randomized controlled trial in Alberta who received primary THA between April 2005 and June 2006 (sex, age, body mass index [BMI], comorbidities, back pain and need for another lower limb arthroplasty procedure within 1 yr after surgery). The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and 36-Item Short Form Health Survey (SF-36) mental health component were administered before surgery and 1 year after. We conducted multiple linear regression to determine the effect of mental health on the WOMAC score at 1 year. Results: The mean WOMAC and SF-36 mental health scores were significantly increased at 1 year (p < 0.001 and p = 0.01, respectively). There was a strong correlation between improvement in WOMAC score at 1 year and presurgery SF-36 mental health score (0.13, 95% confidence interval [CI] 0.06 to 0.2). Age (-0.34, 95% CI -0.45 to -0.24), obesity (-2.9, 95% CI -5.32 to -0.4), back pain (-5.75, 95% CI -8.04 to -3.46) and awaiting another joint arthroplasty operation (-6.18, 95% CI -8.9 to -3.47) had a negative impact on the WOMAC score. Conclusion: There was a strong correlation between presurgery mental health and the resolution of pain and improved functioning 1 year after THA. We recommend that patients receive appropriate counselling and, where appropriate, medical therapy before THA.