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

Abstract

Objective. To estimate and compare the direct and indirect costs of osteoarthritis (OA) in multiethnic Asian patients with OA in Singapore. Methods. 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. Results. 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 to $7477 for Chinese, $1362-$7211 for Malays, $1688-56226 for Indians, and $1437-$12,140 for other ethnic patients; direct costs to society ranged from $3351 to $15,799 for Chinese, $2939-$15, 436 for Malays, $3150-$10,990 for Indians, and $2597-$ 17,879 for other ethnic patients. In contrast, the indirect costs ranged from $1215 to $3834 for Chinese, $1138-$6116 for Malays, and $1371-$5292 for Indians. However, most ethnic variations were not statistically significant. Conclusion. 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.