Background: Osteoporosis, a reduction in bone strength, is one of the most significant factors contributing to fractures, particularly in postmenopausal women. It affects not only patients’ life expectancy and quality of life, but also household expenditure on healthcare costs. Various screening methods to identify the risk of developing osteoporosis and medications to reduce the risk of fractures among osteoporosis patients are currently available in the healthcare market. The objectives of this study were to assess the value for money and budget impact of the screening and treatment of postmenopausal osteoporosis. The results will be useful for decision makers and reimbursement policies in Thailand.
Methods: A cost-utility analysis and a budget impact analysis were conducted in order to compare screening and treatment modalities for postmenopausal osteoporosis. Various screening options and sequential confirmation of high-risk patients with osteoporosis were compared with ‘no screening’ option. Primary prevention and secondary prevention of osteoporotic fractures using alendronate, risedronate, ibandronate, zoledronic acid, raloxifene, tibolone, vitamin K2, strontium ranelate and teriparatide were compared with calcium and vitamin D.
Decision analytic models were constructed from both a provider’s perspective and a societal perspective. The efficacy of osteoporosis drugs was obtained from systematic review and meta-analysis. The service costs and related household expenses were based on the Thai setting. All reported costs were adjusted to present values (2012); future costs and outcomes were discounted at a 3% rate per annum. The willingness-to-pay threshold was set at 120,000 Baht per quality-adjusted life-year (QALY) gained. One-way and probabilistic sensitivity analyses were used to incorporate the impact of parameter uncertainty.
Results: For primary prevention of osteoporotic fractures (alendronate, risedronate, raloxifene and tibolone), alendronate was found to be cost-effective when treating in women with osteoporosis aged 65 and above compared to the baseline. The incremental cost-effectiveness ratio (ICER) was 113,000 Baht per QALY gained, with an incremental cost of 14,023 Baht and incremental QALYs of 0.124 (45 days). The value-for-money of alendronate increases with age. When considering the generic version of alendronate, the ICER was 85,000 Baht per QALY gained while the original version of alendronate provides an ICER at 242,000 Baht per QALY gained.
For secondary prevention of osteoporotic fractures (alendronate, risedronate, ibandronate, zoledronic acid, tibolone, strontium ranelate and teriparatide), alendronate still provides better value-for-money compared to other medications. However, it is not cost-effective given the same age criteria (the price of alendronate should be reduced by 60% in order to meet the threshold). Alendronate will only be considered as a cost-effective option when treating women who have a BMD T-score ≤ -4 and are more than 70 years old. Zoledronic acid is the next best option for secondary prevention of osteoporotic fractures. Its price needs to be reduced by 70%, given the treatment for patients aged 65 and above with a BMD T-score ≤ -2.5.
Screening for osteoporosis using clinical risk indexes, namely Osteoporosis Self-Assessment Tool for Asian (OSTA) and Khon Kaen Osteoporosis study score (KKOS), were found to be cost-effective compared to the no-screening option when applied to women aged 65 years and above. Moreover, all screening strategies were cost-effective when applied to women aged 70 years and above. Screening using KKOS yielded the lowest ICER, followed by OSTA, KKOS and quantitative ultrasound calcaneus measurement (QUS), OSTA and QUS, and the WHO Fracture Risk Assessment Tool (FRAX®), respectively.
The budget impact of alendronate for the prevention of osteoporotic fractures in women aged 65 years and above was 12,866 million Baht per annum (1.18 million patients treated). However, it is not feasible to identify those who need treatment using Dual energy X-ray absorptiometry in all case. Using one of the recommendations from the Royal College of Orthopaedic Surgeons of Thailand (RCOST) and the Thai Osteoporosis Foundation (TOPF), an estimate budget impact of 2,013 million Baht per annum (185,000 patients treated) and 4,330 million Baht per annum (398,000 patients treated) were calculated by applying the FRAX® 10-year probability of major osteoporotic fracture at 20% and 10-year probability of hip fracture at 3% as treatment cut-off points, respectively.
Policy recommendations: At current medication prices, providing generic alendronate as a treatment for postmenopausal osteoporosis in women aged 65 years and above without previous fractures was cost-effective when considered from the societal perspective. However, this policy results in a great impact on the budget of Thai health insurance schemes. Therefore, treatments for osteoporosis should be allocated to those with a higher risk of developing fractures to maintain the sustainability of the Thai healthcare system.