Hip osteoarthritis and risk factors in elderly Korean population

Abstract

Objective: To investigate the prevalence of hip osteoarthritis (OA) in a community-based elderly Korean population and to identify its risk factors.

Design: Radiographs of hip and knee were evaluated in 288 men and 386 women (age>or=65 years) that participated in the Korean Longitudinal Study on Health and Aging (KLoSHA). Minimum joint space widths (JSW), center-edge angles (CEA), and neck-shaft angles were measured on hip radiographs, and tibio-femoral angles on knee radiographs. Hip OA was defined as minimum JSW of <or=2mm or <or=2.5mm. The following potential risk factors of OA were examined; demographic data, acetabular dysplasia, large CEA (>or=40 degrees) and deformities of femoral neck and knee joint. Multivariate analysis with generalized estimating equation (GEE) model was performed to exclude confounding factors.

Results: When hip OA was defined as JSW<or=2mm, the overall prevalence of the disease was 2.1% (95% confidence interval [CI], 1.0-3.2%), and only older age (>or=70 years) was identified as a significant risk factors with an odds ratio (OR) of 10.0. However, when hip OA was defined as a JSW of <or=2.5mm, the overall prevalence of the disease was 13.1% (95% CI, 10.5-15.6%), and older age (>or=70 years), female, large CEA (>or=40 degrees), and acetabular dysplasia (CEA<20 degrees) were identified as significant risk factors with ORs of 2.1, 2.1, 2.3, and 10.2, respectively.

Conclusions: The prevalence of hip OA in elderly Korean was 2.1% (JSW<or=2mm) in community-based population. Older age (>or=70 years), female, large CEA (>or=40 degrees), and acetabular dysplasia (CEA<20 degrees) appeared to be significant risk factors of hip OA.