Health-related quality of life and mobility of patients awaiting elective total hip arthroplasty: a prospective study

Abstract

Background: Waits for elective total hip arthroplasty for osteoarthritis are common in publicly funded health care systems, but they may lead to poorer postoperative outcomes and loss of health-related quality of life (HRQOL) through progressive pain and immobility during the wait. These issues have not been examined from the time of referral for surgery. Our primary objective was to test whether a longer wait was associated with poorer postoperative HRQOL.

Methods: Patients needing possible total hip arthroplasty for osteoarthritis were identified upon referral to a surgeon in London, Ont. Outcome measures, including the Western Ontario McMaster (WOMAC) Osteoarthritis Index and mobility in the 6-Minute Walk, were assessed at baseline and every 3-6 months thereafter until at least 3 months after the surgery.

Results: Of 553 potentially eligible patients referred for surgical assessment, 123 were placed on a waiting list for total hip arthroplasty; 114 underwent the procedure, and 99 of them returned for postoperative assessment. No significant differences in HRQOL or mobility were seen postoperatively between patients with short waits and those with long waits (a priori definitions < or = 6 months and > 6 months respectively). At referral, however, patients with short waits had poorer HRQOL and were less mobile than those with long waits (p = 0.002 for WOMAC Osteoarthritis Index total score, 0.001 for pain, 0.009 for stiffness and 0.008 for function; p = 0.006 for 6-Minute Walk results). Patients with short waits experienced larger gains in these measures from the time of referral until the postoperative assessment than did patients with long waits (p = 0.002 for WOMAC Osteoarthritis Index total score, < 0.001 for pain, 0.005 for stiffness and 0.005 for function; p = 0.06 for 6-Minute Walk results). For patients with long waits, increases in the WOMAC Osteoarthritis Index total score exceeded 10% and losses in walking distance exceeded 30 m from the time of referral to surgery.

Interpretation: The length of wait for elective total hip arthroplasty is not associated with postoperative HRQOL and mobility. However, patients who undergo the procedure within 6 months after referral have greater disability at referral, and realize greater gains in HRQOL and mobility after surgery, than patients waiting more than 6 months. Clinically important losses in HRQOL and mobility occur in patients waiting more than 6 months.

Fig. 1: Cohort ascertainment and follow-up of patients with osteoarthritis of the hip referred for possible total hip arthroplasty in London, Ont.

Fig. 2: Health-related quality of life (HRQOL) and mobility in subgroups of patients defined by time from referral to surgery. Group 1 (n = 24) waited less than 3 months to surgery, group 2 (n = 39) 3–6 months, group 3 (n = 23) 6–12 months, and group 4 (n = 13) over 12 months. Higher values for all WOMAC (Western Ontario McMaster) Osteoarthritis Index scales indicate poorer HRQOL. Means and standard errors are shown. Bar labels: BL = baseline value, 6 = 6-month value, 12 = 12-month value, Pre = value just before surgery, Post = value after surgery.