Predictors of Improvement in Health-Related Quality of Life after Primary Total Knee Arthroplasty

Abstract

BackgroundTo evaluate and analyze patient factors that influence the magnitude of improvement in health-related quality of life in Middle Eastern patients.Patients and MethodsRecords of patients who underwent primary total knee arthroplasty (TKA) were reviewed. The Oxford knee score (OKS) and EuroQoL-5 dimensions 5 levels (EQ. 5D5L) score were filled out by patients preoperatively and at the final follow-up. Patients were divided into two groups using the median improvement in EQ. 5D5L utility as the cutoff value. Univariate and multivariate analyses were used to compare both groups to identify factors that are associated with more improvement in EQ. 5D5L utility.ResultsA total of 130 patients were included, consisting of 66 high gainers and 64 low gainers. At the final follow up, patients in both groups achieved higher OKS and EQ. 5D5L utility scores compared with preoperative values. Univariate analysis showed that patients with grade 4 osteoarthritis, any degree of fixed flexion deformity and worse preoperative EQ. 5D5L utility were more likely to achieve more improvement in utility. Change in OKS did not match the change in EQ. 5D5L utility. Multivariate analysis demonstrated that preoperative utility was the only factor influencing gain in utility. The probability of high gain in EQ. 5D5L utility after TKA in patients with a preoperative utility more than 0.22 was 13% (95% confidence interval: 7.5–21.6). With a lower preoperative utility, the probability of high gain in utility increased to 93.4% (95% confidence interval: 84.6–97.4).ConclusionsPreoperative utility can guide healthcare providers to predict which patients would benefit much after TKA, and thereby prioritize patients with lower preoperative utility.Level of evidence: IV.