The risk of revision after primary total hip arthroplasty among statin users: a nationwide population-based nested case-control study.

BACKGROUND: Statins have been associated with beneficial effects on bone metabolism and inflammation in both experimental and clinical studies. The association between statin use and the risk of revision after primary total hip arthroplasty has not been examined.

METHODS: We identified 2349 patients from the Danish Hip Arthroplasty Registry who underwent revision of a primary total hip replacement in the period from 1996 to 2005 and matched them, using propensity score matching, with 2349 controls with a total hip replacement who had not had a revision. Using conditional logistic regression, we estimated the relative risk of revision due to all causes and due to specific causes according to postoperative statin use.

RESULTS: The ten-year cumulative implant revision rate in the underlying cohort of 57,581 total hip arthroplasties from the registry was 8.9% (95% confidence interval, 8.4% to 9.4%). Postoperative statin use was associated with an adjusted relative risk of revision of 0.34 (95% confidence interval, 0.28 to 0.41) compared with no use of statin. Statin use was associated with a reduced risk of revision due to deep infection, aseptic loosening, dislocation, and periprosthetic fracture. No difference in the risk of revision due to pain or implant failure was found between statin users and nonusers.

CONCLUSIONS: The use of statins was associated with a substantially lower revision risk following primary total hip arthroplasty. Statins, however, should not be prescribed to healthy patients undergoing total hip arthroplasty in order to improve the longevity of the replacement until further studies have confirmed our finding and the mechanisms for this association have been clarified.