Direct and indirect costs of osteoarthritis in Singapore: a comparative study among multiethnic Asian patients with osteoarthritis.

Abstract

To estimate and compare the direct and indirect costs of osteoarthritis (OA) in multiethnic Asian patients with OA in Singapore. The study was a retrospective and cross-sectional design. Patients were stratified according to ethnicity and presence or absence of joint surgery. Direct costs were estimated from both a societal and a patient perspective using the Singapore General Hospital database; indirect costs were estimated using the human capital approach. All costs were expressed as mean costs per patient per annum in 2003 Singapore dollars. A total of 1179 patients (83.6% Chinese, 7.2% Malay, 3.5% Indian, 5.7% others) were included in estimating direct costs, of which 513 (43.5%) had total knee replacement (TKR) and 92 (7.8%) total hip replacement (THR), while 105 patients (71.4% Chinese, 14.3% Malay, 14.3% Indian) were included in estimating indirect costs. Direct costs to patients ranged from 1460 dollars to 7477 dollars for Chinese, 1362 dollars-7211 dollars for Malays, 1688 dollars-6226 dollars for Indians, and 1437 dollars-12,140 dollars for other ethnic patients; direct costs to society ranged from 3351 dollars to 15,799 dollars for Chinese, 2939 dollars-15,436 dollars for Malays, 3150 dollars-10,990 dollars for Indians, and 2597 dollars-17,879 dollars for other ethnic patients. In contrast, the indirect costs ranged from 1215 dollars to 3834 dollars for Chinese, 1138 dollars-6116 dollars for Malays, and 1371 dollars-5292 dollars for Indians. However, most ethnic variations were not statistically significant. The economic burden of OA to society and patients increased by 3-fold or more in the patients with TKR/THR compared to those without. The ethnic differences in health resources consumed were more apparent when the disease progressed.