Nutritional supplements for people being treated for active tuberculosis

UPDATED

Grobler L1, Nagpal S2, Sudarsanam TD3, Sinclair D2

1. Stellenbosch University, Centre for Evidence-based Health Care, Faculty of Medicine and Health Sciences, Cape Town, Western Cape, South Africa
2. Liverpool School of Tropical Medicine, Department of Clinical Sciences, Liverpool, UK
3. Christian Medical College, Medicine Unit 2 and Clinical Epidemiology Unit, Vellore, Tamil Nadu, India

Grobler L, Nagpal S, Sudarsanam TD, Sinclair D. Nutritional supplements for people being treated for active tuberculosis. Cochrane Database of Systematic Reviews 2016, Issue 6. Art. No.: CD006086. DOI: 10.1002/14651858.CD006086.pub4.

To read the updated review, please follow this link: http://onlinelibrary.wiley.com/wol1/doi/10.1002/14651858.CD006086.pub4/full

Nutritional supplements for people being treated for active tuberculosis

Cochrane researchers conducted a review of the effects of nutritional supplements for people being treated for tuberculosis. After searching for relevant studies up to 4 February 2016, they included 35 relevant studies with 8283 participants. Their findings are summarized below.

What is active tuberculosis and how might nutritional supplements work?

Tuberculosis is a bacterial infection which most commonly affects the lungs. Most people who get infected never develop symptoms as their immune system manages to control the bacteria. Active tuberculosis occurs when the infection is no longer contained by the immune system, and typical symptoms are cough, chest pain, fever, night sweats, weight loss, and sometimes coughing up blood. Treatment is with a combination of antibiotic drugs, which must be taken for at least six months.

People with tuberculosis are often malnourished, and malnourished people are at higher risk of developing tuberculosis as their immune system is weakened. Nutritional supplements could help people recover from the illness by strengthening their immune system, and by improving weight gain, and muscle strength, allowing them to return to an active life. Good nutrition requires a daily intake of macronutrients (carbohydrate, protein, and fat), and micronutrients (essential vitamins and minerals).

What the research says

Effect of providing nutritional supplements to people being treated for tuberculosis

We currently don't know if providing free food to tuberculosis patients, as hot meals or ration parcels, reduces death or improves cure (very low quality evidence). However, it probably does improve weight gain in some settings (moderate quality evidence), and may improve quality of life (low quality evidence).

Routinely providing multi-micronutrient supplements may have little or no effect on deaths in HIV-negative people with tuberculosis (low quality evidence), or HIV-positive people who are not taking anti-retroviral therapy (moderate quality evidence). We currently don't know if micronutrient supplements have any effect on tuberculosis treatment outcomes (very low quality evidence), but they may have no effect on weight gain (low quality evidence). No studies have assessed the effect on quality of life.

Plasma levels of vitamin A appear to increase after starting tuberculosis treatment regardless of supplementation. In contrast, supplementation probably does improve plasma levels of zinc, vitamin D, vitamin E, and selenium, but this has not been shown to have clinically important benefits. Despite multiple studies of vitamin D supplementation in different doses, statistically significant benefits on sputum conversion have not been demonstrated.

Authors' conclusions

Food or energy supplements may improve weight gain during recovery from tuberculosis in some settings, but there is currently no evidence that they improve tuberculosis treatment outcomes. There is also currently no reliable evidence that routinely supplementing above recommended daily amounts has clinical benefits.