What Factors Identified in Initial Osteoarthritis Management Are Associated With Poor Patient-reported Outcomes After THA? A Register-based Study
Authors: Gustafsson Kristin , Kvist Joanna , Eriksson Marit , Rolfson Ola 
Published: May 2023

Abstract

Background
Some patients report long-term pain or no improvement in health-related quality of life (HRQoL) or are dissatisfied after THA. However, factors associated with these poorer patient-reported outcomes after surgery are inconsistent and have typically been studied in the late phase of hip osteoarthritis (OA) among patients already eligible for surgery. Earlier identification of risk factors would provide time to address modifiable factors, helping to improve patients’ pain, HRQoL, and satisfaction after surgery and reduce the burden on orthopaedic clinics by referring patients who are better prepared for surgery.

Questions/purposes
We analyzed data from patients with hip OA referred to a first-line OA intervention program in primary healthcare at a stage when they had not been referred for THA, and asked: (1) What percentage of patients who proceed to THA report lack of improvement in pain, lack of improvement in HRQoL as measured by the EQ-5D, or are not satisfied with surgery 1 year after THA? (2) What associations exist between baseline factors at referral to this first-line OA intervention program and these poorer patient-reported outcomes 1 year after THA?

Methods
We included 3411 patients with hip OA (mean age 67 ± 9 years, 63% [2160 of 3411] women) who had been referred for first-line OA interventions between 2008 and 2015 and subsequently underwent THA for OA. All patients were initially identified through the Swedish Osteoarthritis Register, which follows and evaluates patients in a standardized national first-line OA intervention program. Then, we identified those who were also registered in the Swedish Arthroplasty Register with a THA during the study period. We included only those with complete patient-reported outcome measures for pain, HRQoL, and satisfaction preoperatively and 1-year postoperatively, representing 78% (3411 of 4368) of patients, who had the same baseline characteristics as nonrespondents. Multiple logistic regression was used to assess the associations between 14 baseline factors and the aforementioned patient-reported outcomes of pain, HRQoL, and satisfaction 1 year after THA, adjusted for all included factors.

Results
Five percent (156 of 3411) of the study population lacked improvement in pain, 11% (385 of 3411) reported no improvement in HRQoL, and 10% (339 of 3411) reported they were not satisfied with surgery 1 year after THA. Charnley Class C (multiple-joint OA or another condition that affects the ability to walk) was associated with all outcomes: lack of improvement in pain (OR 1.84 [95% CI 1.24 to 2.71]; p = 0.002), lack of improvement in HRQoL (OR 1.83 [95% CI 1.42 to 2.36]; p < 0.001), and not being satisfied (OR 1.40 [95% CI 1.07 to 1.82]; p = 0.01). Older age was associated with a lack of improvement in pain (OR per year 1.03 [95% CI 1.01 to 1.05]; p = 0.02), lack of improvement in HRQoL (OR per year 1.04 [95% CI 1.03 to 1.06]; p < 0.001), and not being satisfied (OR per year 1.03 [95% CI 1.01 to 1.05]; p < 0.001). Depression was associated with a lack of improvement in pain (OR 1.54 [95% CI 1.00 to 2.35]; p = 0.050) and with not being satisfied (OR 1.50 [95% CI 1.11 to 2.04]; p = 0.01) but not with a lack of improvement in HRQoL (OR 1.04 [95% CI 0.76 to 1.43]; p = 0.79). Having four or more comorbidities was associated with a lack of improvement in HRQoL (OR 2.08 [95% CI 1.39 to 3.10]; p < 0.001) but not with a lack of improvement in pain and not being satisfied.

Conclusion
The results of this study showed that older age, Charley Class C, and depression in patients with first-line OA interventions were risk factors associated with poorer outcomes regarding pain, HRQoL, and satisfaction after THA. Screening patients with hip OA for depression early in the disease course would provide increased time to optimize treatments and may contribute to better patient-reported pain, HRQoL, and satisfaction after future THA. Further research should focus on identifying the optimal time for surgery in patients with depression, as well as what targeted interventions for depression can improve outcome of surgery in these patients.

Level of Evidence
Level III, therapeutic study.