The story so far: According to recent reports in The Lancet and The Lancet Global Health, nutritional support has helped prevent both tuberculosis (TB) among household contacts and mortality among TB patients in a trial in Jharkhand. In 2017, the World Health Organization had estimated that undernutrition is responsible for twice the number of TB cases than HIV globally. Any attempt to end/eliminate TB in India by 2025 will become possible only if undernutrition among people is addressed. As per conservative estimates, 40% of new TB cases annually in India are due to undernutrition.
What are the key achievements of the trial?
A large field-based trial was undertaken between August 2019 and August 2022 in four districts of Jharkhand by a team led by Dr. Anurag Bhargava and Dr. Madhavi Bhargava from the Yenepoya Medical College, Mangaluru in collaboration with the National Tuberculosis Elimination Programme (NTEP) and the National Institute for Research in Tuberculosis-Indian Council of Medical Research (NIRT-ICMR).
The RATIONS (Reducing Activation of Tuberculosis by Improvement of Nutritional Status) trial enrolled 2,800 people with pulmonary TB disease and 10,345 household contacts of TB patients. While all the TB patients received nutritional support, household contacts were randomly assigned to receive either nutritional support or usual diet alone. There were 5,621 household contacts in the intervention arm and 4,724 contacts in the control group.
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While there were 108 (4%) deaths among TB patients across all body weights, mortality among those under 35 kg body weight (severely underweight) was 7%. In comparison, in a study carried out by the Chennai-based NIRT in Tiruvallur district, Tamil Nadu, which did not provide any nutrition support to the TB patients, mortality was 14% in those weighing under 35 kg; mortality dropped to 4% among those weighing over 35 kg. Incidence of TB deaths reduced by 12% with a one-unit increase in BMI and by 23% for a two-unit increase in BMI. With the nutritional support, at six months, the proportion of those with normal BMI increased from 16.5% to 43.5%. In general, extreme undernutrition — BMI less than 13 in men and BMI less than 11 in women — can often be fatal. However, in the current trial, more than 85% of such TB patients survived with nutritional support. Over 80% of TB patients had a BMI less than 18.5 and nearly 49% had a BMI less than 16 (severely underweight). There was 5% weight gain in the first two months which was associated with 60% lower risk of TB mortality. As per a 2022 study undertaken in India, the absence of weight gain during treatment in patients with severe undernutrition was associated with a five-fold higher death rate.
Among the household contacts, nutritional support led to a 39%-48% reduction in TB disease in the intervention group compared with the control arm. In the study that lasted for six months, 122 people in the control group developed TB whereas the intervention arm had only 96 TB cases. There was a 39% reduction in TB incidence — pulmonary and extra-pulmonary — while there was 48% reduction in pulmonary TB. The 39%-48% reduction in TB disease in the household contact intervention arm was after adjusting for confounding factors such as TB preventive treatment to children below five years, diabetes, smoking, and alcohol use.
What was the nutritional support provided?
Each adult household contact in the intervention arm received 5 kg of rice, 1.5 kg of split pigeon peas (tur dal), and micronutrient pills every month for six months. Each child (below 10 years) household contact received 50% of the adult nutrition support. Those in the control arm did not get any nutritional supplementation.
For TB patients, monthly nutritional support included 5 kg of rice, 1.5 kg of milk powder, 3 kg of roasted chickpea flour, 500 ml of oil, and micronutrient pills for a period of six months for people with drug-susceptible TB, and 12 months for people with MDR-TB.
What effect does undernutrition have on TB incidence, treatment outcomes?
Many new cases of TB are attributable to five risk factors — undernourishment, HIV infection, alcohol use disorders, smoking (especially among men) and diabetes, says the WHO Global TB report 2022. In TB-endemic countries such as India, undernutrition is the most widely prevalent risk factor, accounting for the “highest population attributable risk for TB in India”. It is also responsible for increased TB disease severity, higher mortality and poor treatment outcomes. As per the SDG 2 goal 2030 to end hunger and ensure access to nutritious food by all people year-round, the rationale is that undernutrition weakens the body’s defence against infections and is a strong risk factor for TB disease.
A study in India found that severe undernutrition at diagnosis was associated with a two-fold higher risk of death. As per a 2016 paper by NIRT researchers, undernutrition is an important risk factor for progression of latent TB infection to TB disease. It increases the risk of drug toxicity, TB relapse and mortality. For each unit reduction in BMI, the risk of TB increases by about 14%. Undernourished patients also tend to have poor bioavailability of drugs such as rifampicin, leading to treatment failure and development of multidrug resistance.
How do schemes like Nikshay Poshan Yojana and Ni-kshay Mitra help?
Nikshay Poshan Yojana is a direct benefit transfer (DBT) scheme for nutritional support to TB patients. It was launched in April 2018. All notified TB cases are provided with a financial incentive of ₹500 per month. According to the 2022 India TB report, seven million TB patients have benefited between 2018 and 2022, and ₹2,089 crore has been disbursed during this period.
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Late last year, India introduced Ni-kshay Mitras — volunteers adopting and caring for TB patients by providing nutritional support, nutritional supplements, among other things. As of March 9, 2023, 9.55 lakh consented TB patients across the country have been adopted by Ni-kshay Mitras. But in 2022, 2.4 million fresh TB cases were notified.
- In 2017, the World Health Organization had estimated that undernutrition is responsible for twice the number of TB cases than HIV globally.
- Many new cases of TB are attributable to five risk factors — undernourishment, HIV infection, alcohol use disorders, smoking (especially among men) and diabetes, says the WHO Global TB report 2022.
- Any attempt to end/eliminate TB in India by 2025 will become possible only if undernutrition among people is addressed.
