The Fracture Risk Assessment Tool (FRAX) has been used universally for the purpose of fracture risk assessment. However, the predictive capacity of FRAX for autoimmune diseases remains inconclusive. This study aimed to compare the applicability of FRAX for autoimmune disease patients. This retrospective study recruited rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and primary Sjögren syndrome (pSS) patients with bone mineral density (BMD) tests. Patients with any osteoporotic fractures were identified. Taiwan-specific FRAX with and without BMD were then calculated. In total, 802 patients (451 RA, 233 SLE and 118 pSS) were enrolled in this study. The cumulative incidences of osteoporotic fractures in the RA, SLE and pSS patients were 43.0%, 29.2% and 33.1%, respectively. For those with a previous osteoporotic fracture, T-scores were classified as low bone mass. Overall, the patients' 10-year probability of major fracture risk by FRAX without BMD was 15.8%, which then increased to 20.3% after incorporation of BMD measurement. When analyzed by disease group, the fracture risk in RA patients was accurately predicted by FRAX. In contrast, current FRAX, either with or without BMD measurement, underestimated the fracture risk both in SLE and pSS patients, even after stratification by age and glucocorticoid treatment. For pSS patients with major osteoporotic fractures, FRAX risks imputed by RA were comparable to major osteoporotic fracture risks of RA patients. Current FRAX accurately predicted fracture probability in RA patients, but not in SLE and pSS patients. RA-imputed FRAX risk scores could be used as a temporary substitute for SLE and pSS patients.
INTRODUCTION: Glucocorticoid therapy is associated with an appreciable risk of bone loss leading to fractures that require expensive treatments. This study aimed to evaluate the cost-effectiveness of bisphosphonates for prevention of hip fracture in glucocorticoid-induced osteoporosis (GIOP) in Malaysia.
METHOD: Retrospective data were collected from GIOP patients referred to the Universiti Kebangsaan Malaysia Medical Centre. Fracture events and direct medical costs were compared between bisphosphonates and calcium/vitamin D combination.
RESULTS: Fracture events were reported in 28 out of 93 included patients, with hip and vertebral fractures representing 42.9% and 35.7%, respectively. Overall, the use of bisphosphonates could not be considered cost-effective for treatment of all GIOP patients. The presence of certain fracture risk factors was able to modify the cost-effectiveness of bisphosphonates. Bisphosphonates was considered cost-effective if started in patients more than 60 years old. However, the use of bisphosphonates was not cost-effective in GIOP patients with secondary osteoporosis. The incremental cost-effectiveness ratios (ICER) of bisphosphonates in patients with risk factors of previous fracture or rheumatoid arthritis were Malaysian Ringgits (MYR) 108 603.40 and MYR 25 699.21, respectively.
CONCLUSION: Fracture risk factors of age, previous fracture, rheumatoid arthritis and secondary osteoporosis may modify the cost-effectiveness outcomes of bisphosphonates. Bisphosphonates would be considered cost-effective in patients more than 60 years old as compared to calcium/vitamin D treatments. Further evaluation of the impact of fracture risk factors in larger populations would provide more precise information to better assist rational and economical use of anti-osteoporosis treatment in GIOP patients.