Cost-Effectiveness of TB Preventive Treatment for People Living With HIV/AIDS

Short-course tuberculosis (TB) preventive treatment is likely to be cost-effective for reducing the burden of TB among people living with HIV/AIDS (PLWHA) and household contacts, according to recent findings. 

TB remains a significant global health concern, particularly in high-incidence countries, researchers said. Preventive measures have been established to reduce the burden of TB, especially among vulnerable populations like PLWHA and household contacts. However, guidelines and implementation of TB preventive treatment (TPT) vary based on age and HIV status, and cost remains a major barrier to its widespread adoption, researchers said.

To address the cost-effectiveness of TPT for PLWHA and household contacts, researchers conducted a comprehensive study using a state-transition model. This model simulated short-course TPT for PLWHA and household contacts in 29 high-incidence countries. The primary outcome measure was the incremental cost-effectiveness ratio, which quantifies the cost per incremental disability-adjusted life year (DALY) averted compared to a scenario without any TPT or contact investigation.

The study findings revealed that scaling up TPT between 2023 and 2035 could prevent a considerable number of TB cases and deaths among PLWHA and household contacts. Specifically, it prevented 0.9 individuals (with a 95% uncertainty interval of 0.4 to 1.6) from developing TB and 0.13 (0.05 to 0.27) TB-related deaths per 100 PLWHA. The incremental cost of providing TPT to PLWHA was $15 (ranging from $9 to $21) per person.

Similarly, for household contacts, TPT, when combined with contact investigation, averted 1.1 cases (with an uncertainty interval of 0.5 to 2.0) and 0.7 deaths (0.4 to 1.0) per 100 contacts at a cost of $21 (ranging from $17 to $25) per contact. The cost-effectiveness analysis showed that TPT was most favorable for household contacts younger than 5 years, with a cost of $22 per DALY averted, followed by contacts aged 5 to 14 years, with a cost of $104 per DALY averted. For PLWHA, the cost per DALY averted was $722, and for adult contacts, it was $309.

The cost-effectiveness of TPT remained promising in several sensitivity analyses, which evaluated different aspects, such as screening algorithms, TPT regimens, time horizons, TPT coverage, antiretroviral therapy discontinuation, and secondary transmission benefits. In particular, a longer time horizon and the inclusion of secondary transmission benefits made TPT even more favorable in terms of cost-effectiveness.

“Short-course TPT was also cost-effective for adult contacts in 15 of 29 countries and for PLWHA in seven countries, although these conclusions vary depending on the cost-effectiveness threshold used,” researchers noted. 

The investigators emphasized that short-course TPT is likely to be cost-effective for PLWHA and household contacts of all ages, irrespective of whether contact investigation is already in place. The researchers warned that failing to implement tuberculosis contact investigation and TPT could lead to a significant burden of preventable illness and mortality in the next decade.

Reference:
Ryckman T, Weiser J, Gombe M, et al. Impact and cost-effectiveness of short-course tuberculosis preventive treatment for household contacts and people with HIV in 29 high-incidence countries: a modelling analysis. Lancet Glob Health. 2023;11(8):e1205-e1216. doi:10.1016/S2214-109X(23)00251-6