ABSTRACT
Background: Undernutrition is the leading cause of tuberculosis (TB) globally, but nutritional interventions are often considered cost prohibitive. The RATIONS study demonstrated that nutritional support provided to household contacts of persons with TB can reduce TB incidence. However, the long-term cost-effectiveness of this intervention is unclear. Methods: We assessed the cost-effectiveness of a RATIONS-style intervention (daily 750 kcal dietary supplementation and multi-micronutrient tablet). Using a Markov state transition model we simulated TB incidence, treatment, and TB-attributable mortality among household contacts receiving the RATIONS intervention, as compared to no nutritional support. We calculated health outcomes (TB cases, TB deaths, and disability-adjusted life years [DALYs]) over the lifetime of intervention recipients and assessed costs from government and societal perspectives. We tested the robustness of results to parameter changes via deterministic and probabilistic sensitivity analysis. Findings: Over two years, household contacts receiving the RATIONS intervention would experience 39% (95% uncertainty interval (UI): 23-52) fewer TB cases and 59% (95% UI: 44-69) fewer TB deaths. The intervention was estimated to avert 13,775 (95% UI: 9036-20,199) TB DALYs over the lifetime of the study cohort comprising 100,000 household contacts and was cost-effective from both government (incremental cost-effectiveness ratio: $229 per DALY averted [95% UI: 133-387]) and societal perspectives ($184 per DALY averted [95% UI: 83-344]). The results were most sensitive to the cost of the nutritional supplement. Interpretation: Prompt nutritional support for household contacts of persons with TB disease would be cost-effective in reducing TB incidence and mortality in India. Summary: Undernutrition is the leading cause of tuberculosis in India. Using a Markov state-transition model, we found that food baskets for household contacts of persons with tuberculosis would be cost-effective in reducing tuberculosis incidence and mortality in India. Research in context: Evidence before this study: Undernutrition is the leading risk factor for TB worldwide. Recently, the RATIONS study demonstrated a roughly 40% reduction in incident TB among household contacts who received in-kind macronutrient and micronutrient supplementation. Added value of this study: Although the RATIONS study demonstrated a dramatic reduction in incident TB, it is unclear if nutritional interventions to prevent TB are cost-effective. Previously, only one cost-effectiveness analysis of nutritional interventions for household contacts has been published. Due to lack of published data, that study had to make assumptions regarding the impact of nutritional interventions on TB incidence and mortality. In this study, we conducted an economic evaluation of a RATIONS-style intervention to reduce incident TB and mortality in India using observed data. Implications of all the available evidence: In-kind nutritional supplementation for household contacts of individuals with TB disease would be cost-effective in reducing incident TB and TB mortality, particularly if TB programs leverage economies of scale to bring down the cost of the nutritional intervention.
ABSTRACT
Tuberculosis (TB) is a major cause of death worldwide, with 1.5 million deaths in 2020. While TB incidence and mortality had previously been on a downwards trend, in 2020, TB mortality actually rose for the first time in a decade, largely due to the COVID-19 pandemic. Undernutrition is the leading risk factor for TB, with a population attributable fraction (PAF) of 15%, compared to 7.6% for HIV. Individuals who are undernourished are more likely to develop active TB compared to those with a healthy bodyweight. They are also more likely to have greater severity of TB, and less likely to have successful TB treatment outcomes. The likelihood of TB mortality significantly increases as weight decreases. Nutritional interventions are likely to improve both nutritional status and TB treatment success, thereby decreasing TB mortality. However, many previous studies focusing on nutritional interventions have provided insufficient calories or been underpowered. Nutritional supplementation will be particularly important as factors such as the COVID-19 pandemic, climate change, and political conflict further threaten food security. The global TB elimination effort can no longer afford to ignore undernutrition.
ABSTRACT
BACKGROUND: Undernutrition is the leading cause of tuberculosis (TB) in India and is associated with increased TB mortality. Undernutrition also decreases quality of life and economic productivity. METHODS: We assessed the cost-effectiveness of providing augmented rations to undernourished Indians through the government's Targeted Public Distribution System (TPDS). We used Markov state transition models to simulate disease progression and mortality among undernourished individuals in 3 groups: general population, household contacts (HHCs) of people living with TB, and persons living with human immunodeficiency virus (HIV). The models calculate costs and outcomes (TB cases, TB deaths, and disability-adjusted life years [DALYs]) associated with a 2600 kcal/day diet for adults with body mass index (BMI) of 16-18.4 kg/m2 until they attain a BMI of 20 kg/m2 compared to a status quo scenario wherein TPDS rations are unchanged. We employed deterministic and probabilistic sensitivity analyses to test result robustness. RESULTS: Over 5 years, augmented rations could avert 81% of TB cases and 88% of TB deaths among currently undernourished Indians. Correspondingly, this intervention could forestall 78% and 48% of TB cases and prevent 88% and 70% of deaths among undernourished HHCs and persons with HIV, respectively. Augmented rations resulted in 10-fold higher resolution of undernutrition and were highly cost-effective with (incremental cost-effectiveness ratio [ICER] of $470/DALY averted). ICER was lower for HHCs ($360/DALY averted) and the HIV population ($250/DALY averted). CONCLUSIONS: A robust nutritional intervention would be highly cost-effective in reducing TB incidence and mortality while reducing chronic undernutrition in India.
