Cost-effectiveness of selective bone densitometry using the osteoporosis self-assessment tool for Asians in multi-ethnic Asian population

Early detection and treatment of osteoporosis can help to prevent debilitating fractures in the elderly. The osteoporosis self-assessment tool for Asians can be used as a screening tool to stratify patients for bone densitometry. It is most cost-effective for post-menopausal women aged 70 and males aged 75.To determine the cost-effectiveness of selective bone densitometry (SBD) using the Osteoporosis Self-Assessment Tool for Asians (OSTA) as a risk-stratifying tool for the three predominant races (Chinese, Malay and Indian) in Singapore.Decision analytical models were developed using a Markov model. Three scenarios were compared: no bone densitometry, SBD using the OSTA as a pre-screening tool and universal bone densitometry. Those diagnosed with osteoporosis were treated with five years of alendronate therapy. Data sources were from Singapore epidemiological studies, healthcare cost figures and published literature. Measurements include life years, quality-adjusted life years (QALYs), costs and incremental cost-effectiveness ratios (ICER).Compared to no bone densitometry, SBD using the OSTA would cost between $40,679 and $73,909 per QALY gained for men aged 75-80 and $22,386 to $58,185 per QALY gained for post-menopausal women aged 70-80. Universal bone densitometry would cost $157,955 to $177,127 per QALY gained for men aged 75-80 and $40,179 to $66,112 per QALY gained for post-menopausal women aged 70 to 80 compared to SBD.In general, osteoporosis screening was the most cost-effective for Malays and the least cost-effective for Indians. However, a general guideline should still be applied to the Singaporean population, as further explained later. Overall, the most cost-effective strategy for males would be using OSTA as a risk-stratifying tool at age 75. For post-menopausal women, SBD should be used for women aged 70, while universal bone densitometry should be used for women aged 75-80.