title: Cirrhosis is a risk factor for total hip arthroplasty for avascular necrosis.
abstract: Background and purpose - There are limited data on risk factors for avascular necrosis of the hip, but cirrhosis has been proposed as a risk factor. We examined the association between cirrhosis and incidence of total hip arthroplasty for avascular necrosis. Methods - We used nationwide healthcare data to identify all Danish residents diagnosed with cirrhosis in 1994-2011, and matched them 1:5 by age and sex to non-cirrhotic reference individuals from the general population. We excluded people with a previous total hip arthroplasty, a previous hip fracture, or a previous diagnosis of avascular necrosis. We used stratified Cox regression to estimate the hazard ratio (HR) for cirrhosis patients relative to reference individuals, adjusting for potential confounders. We used the cumulative incidence function to compute 5-year risks. Results - We included 25,421 cirrhosis patients and 114,052 reference individuals. Their median age was 57 years, and 65% were men. 45 cirrhosis patients and 44 reference individuals underwent total hip arthroplasty for avascular necrosis. Cirrhosis patients' HR for a total hip arthroplasty for avascular necrosis was 10 (95% CI: 6-17), yet their 5-year risk of avascular necrosis was only 0.2%. For the reference individuals, the 5-year risk was 0.02%. Interpretation - Cirrhosis is a strong risk factor for avascular necrosis of the hip, but it is rare even in cirrhosis patients.
authors.affiliation: a Department of Hepatology and Gastroenterology , Aarhus University Hospital , Aarhus .|b Department of Clinical Epidemiology , Aarhus University Hospital , Aarhus .
authors.forename: Thomas
authors.initials: T
authors.lastname: Deleuran
authors.affiliation: c Department of Orthopedic Surgery and Traumatology , Odense University Hospital, Institute of Clinical Research, University of Southern Denmark , Odense , Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Overgaard
authors.affiliation: a Department of Hepatology and Gastroenterology , Aarhus University Hospital , Aarhus .
authors.forename: Hendrik
authors.initials: H
authors.lastname: Vilstrup
authors.affiliation: a Department of Hepatology and Gastroenterology , Aarhus University Hospital , Aarhus .|b Department of Clinical Epidemiology , Aarhus University Hospital , Aarhus .
authors.forename: Peter
authors.initials: P
authors.lastname: Jepsen
mesh_terms: D019644:Arthroplasty, Replacement, Hip; D006801:Humans; D015994:Incidence; D008103:Liver Cirrhosis; D008875:Middle Aged; D010020:Osteonecrosis; D012307:Risk Factors