HIV/AIDS has long been synonymous with wasting and weight loss. For example, in South Africa, it was known as “slims” disease. Coupled with this, it’s known that adequate nutrition is important for optimal immune and metabolic function and, so, one might expect that dietary support would improve clinical outcomes in HIV-infected individuals by reducing HIV-related complications and attenuating progression of HIV disease. This should lead to better quality of life and, ultimately, less disease-related mortality. Therefore, this Cochrane Review from February 2013 examines the experimental evidence for the effects of nutritional interventions given orally on important clinical outcomes for adults and children with HIV infection and finds that there is relatively little research to help decision makers.
The authors searched many databases, trawled through references and contacted people working in the area. However, only 14 relatively small, randomized trials came to light, which met their inclusion criteria. Just three of these reported on mortality, two that had recruited adults and the other, from South Africa, had recruited children.
A wide range of macronutrient supplements were studied with just two of the trials (one in adults and one in children) studying the same one, a food supplement called Spirulina. There was also wide variation in other aspects of the trials, including the outcomes that were measured and reported and the types of people who took part, in relation to stage of HIV, HIV treatment status and general nutrient status. When the authors assessed the quality of the trials, none of the trials were graded as providing strong evidence. This was mostly because the trials were small and had a high risk of bias due to a lack of blinding and the large proportion of people who left the trials early.
The latest version of the review is an update of the earlier review from 2007, which had included 8 trials from high-income countries, with fewer than 500 HIV+ adults in total. Patients with confirmed secondary infections or other signs and symptoms of infection, such as fever, chills, or persistent diarrhea, were not eligible for any of those trials. This made it difficult to determine the applicability of the findings to the types of people who are most likely to need effective macronutrient supplementation. Six new studies have been added in the update, bringing the number of participants to more than 1700 adults and nearly 300 children. Four of the new trials are from Africa, and there is one from Brazil and one from India. The new trials also include two trials that had recruited participants with opportunistic infections (tuberculosis and persistent diarrhea).
Bringing the evidence together and, where possible, combining the findings of similar trials in meta-analyses identified no significant benefits for supplementary food, daily supplement of Spirulina or a nutritional supplement enhanced with protein with respect to death in HIV+ adults and children. In HIV+ adults with weight loss, nutritionally balanced macronutrient supplements aimed at improving energy intake by 600-960 kcal/day increased intakes of energy and protein compared with no supplement or nutrition counselling alone, but had no effect on other anthropometric or immunologic parameters. From the meta-analyses, supplementation with macronutrient formulas given to provide protein, energy or both and fortified with micronutrients, in conjunction with nutrition counselling, significantly improved energy intake (3 trials; n=131; MD 394 kcal/day; 95% CI: 225 to 562; p<0.00001) and protein intake (2 trials; n=81; MD 23.5 g/day; 95% CI: 12.7 to 34.0; p<0.00001) compared with no nutritional supplementation or nutrition counselling alone.
The authors conclude that supplementation with specific macronutrients such as amino acids, whey protein concentrate or Spirulina did not significantly alter clinical, anthropometric or immunological outcomes in HIV-infected adults and children. They call for future research that takes better account of the needs and resources of the HIV+ individual, the clinician treating them and the people caring for them. They highlight areas of ongoing uncertainty, including the choice between using resources for antiretroviral treatment for HIV+ people or nutritional interventions, the populations that might benefit most (e.g. malnourished HIV+ people, HIV+ people with uncontrolled weight loss, HIV+ people with opportunistic infections or HIV+ lactating mothers), the role of nutritional counseling compared to nutritional interventions in well-resourced settings, and how the use of anti-retroviral therapy might make it difficult to detect the effects of nutritional interventions.