A cost-effectiveness evaluation of methods for screening for TB infection in patients with diabetes mellitus

BACKGROUND: Globally, 10.6 million TB cases occurred in 2021. Malaysia reported 25,000 TB cases in 2022, and also has a high prevalence of diabetes mellitus (DM), amplifying TB risks. OBJECTIVE: Assess the cost-effectiveness of QuantiFERON (QFT-plus) versus tuberculin skin test (TST) for diagnosing TB infection in patients with DM in Malaysia. METHODS: Using an R-based model, we compared QFT-plus to TST. The analysis included individuals with HbA1C >10%. Primary outcomes encompassed costs, quality-adjusted life-years (QALYs), and averted TB cases. RESULTS: QFT-plus costs US$111.29 per person versus US$285.66 for TST. It generated 16.51 QALYs per person, compared to 16.50 QALYs for TST. Despite higher initial screening costs, its improved diagnostic accuracy enables earlier treatment, reducing active TB progression risk by 26% compared to TST. Both deterministic and probabilistic sensitivity analyses consistently favoured QFT-plus. CONCLUSION: Despite its higher initial cost, QFT-plus is both more economical and clinically superior to TST in the context of Malaysia's high prevalence of DM. This underscores the need for its broader adoption through policy shifts to incorporate QFT-plus into national guidelines. Future research should address implementation and broader socio-economic aspects.