A COMPARISON OF PATIENT CHARACTERISTICS AND OUTCOME FOLLOWING TOTAL HIP ARTHROPLASTY IN PUBLIC AND PRIVATE HOSPITALS IN DENMARK

Abstract

Background: A general increase in total number of primary total hip arthroplasty (THA) has been observed in Denmark from 3.828 in 1995 to 7.645 in 2006. During the same period the number of pa-tients treated at private clinics has also increased. To our knowledge no studies, comparing patient characteristics and treatment quality between public and private hospitals, have been published.

We compared patients’ characteristics and outcome following THA in private and public hos-pitals.

Materials and Methods: We used data from the Danish Hip Arthroplasty Registry to identify 69 249 primary THA’ies performed between 1 January 1995 to 31 December 2006.

To detect eventual difference in patient characteristics- age, gender, diagnosis leading to THA, Carlson’s comorbidity score and Charnley category were evaluated.

We matched 3 658 cases operated in private with 3 658 controllers operated in public hospitals on propensity score. Scoring parameters were age, gender, diagnosis leading to THA, Carlson’s comorbidity score, Charnley category, operating time, type of anesthesia and type of prosthesis.

We used multivariate logistic regression on propensity score matched data to assess association between type of hospital and outcome by computing relative risks and 95% Confidence Interval (CI). Outcomes were perioperative complications, readmission within 3 months, re-operation within 2 years, implant failure after 5 years, and mortality within 3 months of surgery.

Results: Private hospitals operated on older females, patients with primary osteoarthritis and low comorbidity and Charnley category 1.

Patients in private and propensity matched controls from public hospitals showed no differences in age, gender, diagnosis leading to THA, Carlson’s comorbidity score, Charnley category, operating time, type of anesthesia and type of prosthesis (p-value < 0,0001).

Based on matched data, private hospitals had lower relative risk for perioperative complications (0.39, 0.26–0.60), reoperations (0.59, 0.41–0.83) and readmissions (0.57, 0.42–0.77) compared with public. There was no difference in mortality or implant failure.

Discussion and Conclusions: We had no data on surgeon, general health and socioeconomic status of the patients. In addition, reported data from private clinics have not been validated in contrast to public hospitals

We found significant difference between patient characteristics operated at public versus private hospitals. No difference was evident regarding mortality and implant failure but for complications, reoperations and readmissions between private and public hospitals.