Email updates

Keep up to date with the latest news and content from Arthritis Research & Therapy and BioMed Central.

Open Access Research article

Decrease in the incidence of total hip arthroplasties in patients with rheumatoid arthritis - results from a well defined population in south Sweden

Korosh Hekmat1*, Lennart Jacobsson1, Jan-Åke Nilsson1, Ingemar F Petersson2, Otto Robertsson2, Göran Garellick3 and Carl Turesson1

Author Affiliations

1 Section of Rheumatology, Department of Clinical Sciences, Malmö, Lund University and Skåne University Hospital, Södra Förstadsgatan 101, 205 02 Malmö, Sweden

2 Orthopedics, Department of Clinical Sciences Lund, Lund University and Skåne University Hospital, Södra Förstadsgatan 101, 205 02 Malmö, Sweden

3 Department of Orthopaedics, Swedish Hip Arthroplasty Register, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Blå Stråket 5, 413 45 Gothenburg, Sweden

For all author emails, please log on.

Arthritis Research & Therapy 2011, 13:R67  doi:10.1186/ar3328

Published: 21 April 2011

Abstract

Introduction

One aim of modern pharmacologic treatment in rheumatoid arthritis (RA) is to prevent joint destruction and reduce the need for surgery. Our purpose was to investigate secular trends in the incidence of primary total hip and knee arthroplasties in a well defined sample of patients with RA.

Methods

Prevalent cases with RA in 1997 and incident cases from 1997 to 2007 in a community based register in Malmö, south Sweden, were included. Based on a structured review of the medical records, patients were classified according to the 1987 ACR criteria for RA. This cohort was linked to the Swedish Hip Arthroplasty Register (through December 2006) and the Swedish Knee Arthroplasty Register (through October 2007). Patients with a registered total hip or knee arthroplasty before 1997 or before RA diagnosis were excluded. Incidence rates for the period of introduction of TNF inhibitors (1998 to 2001) were compared to the period when biologics were part of the established treatment for severe RA (2002 to 2006/2007).

Results

In the cohort (n = 2,164; 71% women) a primary hip arthroplasty was registered for 115 patients and a primary knee arthroplasty for 82 patients. The incidence of primary total hip arthroplasties decreased from the period 1998 to 2001 (12.6/1,000 person-years (pyr)) to 2002 to 2006 (6.6/1,000 pyr) (rate ratio (RR) 0.52; 95% confidence interval (CI) 0.35 to 0.76). There was a trend towards an increase of primary knee arthroplasties (incidence 4.8/1,000 pyr vs. 6.8/1,000 pyr; RR 1.43; 95% CI 0.89 to 2.31).

Conclusions

Our investigation shows a significant decrease in the incidence of total hip arthroplasties in patients with RA after 2001. Possible explanations include a positive effect on joint damage from more aggressive pharmacological treatment.