COST-EFFECTIVENESS OF ORAL BISPHOSPHONATES FOR OSTEOPENIA IN SINGAPORE: IMPLICATIONS FOR RISK-BASED INTERVENTION THRESHOLDS
Author(s)
Sonja CJH Chua, BSc (Pharm) (Hon), PhD1, Johanan Dravium Ponniah, BSc (Hons)1, Valentina Ricci, BSc (Physio), MSc (Social Epidemiology)1, Phyllis AL Kim, MBChB, MPH1, Nicholas Graves, BA, MSc, PhD2, Mohamed Ismail Abdul Aziz, MSc1, Ye Sun, BSc (Hon), PhD1.
1Agency for Care Effectiveness (ACE), Ministry of Health, Singapore, Singapore, 2Health Services and Systems Research, Duke-NUS, Singapore, Singapore.
1Agency for Care Effectiveness (ACE), Ministry of Health, Singapore, Singapore, 2Health Services and Systems Research, Duke-NUS, Singapore, Singapore.
OBJECTIVES: Pharmacological treatment of osteopenia in Singapore has traditionally been guided by the 2008 US National Osteoporosis Foundation intervention thresholds: a 10-year hip fracture (HF) risk of 3% or major osteoporotic fracture (MOF) risk of 20%. As these thresholds were derived using US epidemiology and costs, their applicability to Singapore is uncertain. This study evaluated the cost-effectiveness of oral bisphosphonate therapy in osteopenia using local data to inform risk-based intervention thresholds.
METHODS: A Markov model was developed for adults aged 50-84 years with osteopenia from the healthcare system perspective over a 10-year horizon. Model inputs were derived from National Electronic Health Records data and published literature. Model uncertainty was evaluated using probabilistic sensitivity analysis with 10,000 Monte Carlo simulations. Threshold analysis estimated the fracture risk (both HF and MOF) at which treatment achieved at least 50% probability of being cost-effective at commonly accepted willingness-to-pay (WTP) thresholds.
RESULTS: Across a range of WTP thresholds, cost-effectiveness improved with increasing fracture risk, with treatment becoming cost-saving in higher-risk scenarios. In addition, cost-effectiveness varied substantially by age and sex. For example, at a 10-year HF risk of 3% and a WTP of $50,000 per QALY, treatment was more likely to be cost-effective among women aged 65 to 69 years (65.4% probability) than among women aged 70 to 74 years (42.6% probability), supporting age-specific intervention thresholds. Similarly, treatment generally became cost-effective at lower fracture risk levels among men than women for MOF (across age groups) and HF (in those aged 65 years and above), which supports sex-specific intervention thresholds.
CONCLUSIONS: These findings provided an economic basis for establishing intervention thresholds in our national osteoporosis guidelines (published Aug 2025), where cost-effectiveness is considered alongside clinical benefits and harms, patient factors, and implementation considerations. Efforts are ongoing to integrate fracture-risk assessment tools to facilitate implementation while preserving individualised decision-making.
METHODS: A Markov model was developed for adults aged 50-84 years with osteopenia from the healthcare system perspective over a 10-year horizon. Model inputs were derived from National Electronic Health Records data and published literature. Model uncertainty was evaluated using probabilistic sensitivity analysis with 10,000 Monte Carlo simulations. Threshold analysis estimated the fracture risk (both HF and MOF) at which treatment achieved at least 50% probability of being cost-effective at commonly accepted willingness-to-pay (WTP) thresholds.
RESULTS: Across a range of WTP thresholds, cost-effectiveness improved with increasing fracture risk, with treatment becoming cost-saving in higher-risk scenarios. In addition, cost-effectiveness varied substantially by age and sex. For example, at a 10-year HF risk of 3% and a WTP of $50,000 per QALY, treatment was more likely to be cost-effective among women aged 65 to 69 years (65.4% probability) than among women aged 70 to 74 years (42.6% probability), supporting age-specific intervention thresholds. Similarly, treatment generally became cost-effective at lower fracture risk levels among men than women for MOF (across age groups) and HF (in those aged 65 years and above), which supports sex-specific intervention thresholds.
CONCLUSIONS: These findings provided an economic basis for establishing intervention thresholds in our national osteoporosis guidelines (published Aug 2025), where cost-effectiveness is considered alongside clinical benefits and harms, patient factors, and implementation considerations. Efforts are ongoing to integrate fracture-risk assessment tools to facilitate implementation while preserving individualised decision-making.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EE658
Topic
Economic Evaluation, Epidemiology & Public Health, Health Policy & Regulatory
Topic Subcategory
Thresholds & Opportunity Cost
Disease
Musculoskeletal Disorders (Arthritis, Bone Disorders, Osteoporosis, Other Musculoskeletal), No Additional Disease & Conditions/Specialized Treatment Areas