Different patient-reported outcomes in immigrants and patients born in Sweden: 18,791 patients with 1 year follow-up in the Swedish Hip Arthroplasty Registry

Abstract

Background and purpose: Some patients have persistent symptoms after total hip arthroplsty (THA). We investigated whether the proportions of inferior clinical results after total hip arthroplasty-according to the 5 dimensions in the EQ-5D form, and pain and satisfaction according to a visual analog scale (VAS)-are the same in immigrants to Sweden as observed in those born in Sweden.

Methods: Records of total hip arthroplasties performed between 1992 and 2007 were retrieved from the Swedish Hip Arthroplasty Register (SHAR) and cross-matched with data from the National Board of Health and Welfare and also Statistics, Sweden. 18,791 operations (1,451 in immigrants, 7.7%) were eligible for analysis. Logistic and linear regression models including age, sex, diagnosis, type of fixation, comorbidity, surgical approach, marital status, and education level were analyzed. Outcomes were the 5 dimensions in EQ-5D, EQ-VAS, VAS pain, and VAS satisfaction. Preoperative data and data from 1 year postoperatively were studied.

Results: Preoperatively (and after inclusion of covariates in the regression models), all immigrant groups had more negative interference concerning self-care. Immigrants from the Nordic countries outside Sweden and Europe tended to have more problems with their usual activities and patients from Europe and outside Europe more often reported problems with anxiety/depression. Patients born abroad showed an overall tendency to report more pain on the VAS than patients born in Sweden. After the operation, the immigrant groups reported more problems in all the EQ-5D dimensions. After adjustment for covariates including the preoperative baseline value, most of these differences remained except for pain/discomfort and-concerning immigrants from the Nordic countries-also anxiety/depression. After the operation, pain according to VAS had decreased substantially in all groups. The immigrant groups indicated more pain than those born in Sweden, both before and after adjustment for covariates.

Conclusion: The frequency of patients who reported moderate to severe problems, both before and 1 year after the operation, differed for most of the dimensions in EQ-5D between patients born in Sweden and those born outside Sweden.

Figure 1.

Odds ratio for reporting of moderate or severe preoperative problems in 4 of the 5 EQ5D domains. Unadjusted data (top) and adjusted data (bottom) are presented. Pain/discomfort was not analyzed because of poor variability. The risk ratios and their 95% confidence intervals are shown. Bars indicate p-values.

Figure 2.

Odds ratio for reporting of moderate or severe problems 1 year after operation in the 5 EQ5D domains. Unadjusted data (top) and adjusted data (bottom) are presented. The risk ratios and their 95% confidence intervals are shown. Bars indicate p-values.