Nutrition News for Africa

Abstract - January 15, 2006

A study entitled 'Safety and efficacy of zinc supplementation for children with HIV-1 infection in South Africa: a randomised double-blind placebo-controlled trial' by Bobat et al was presented in The Lancet (Vol 366 November 26, 2005).

Background. Zinc is important for growth, immunity and development, and thus a deficiency of this important micronutrient leads to impaired function and an increased risk of infection, particularly among children under 5. Recent research has elucidated the importance of zinc as an adjunct therapy for diarrheal treatment in developing countries. Further research has demonstrated that zinc supplementation for children reduces incidence of pneumonia and may reduce malarial morbidity. However, the relationship between zinc and HIV infection, in particular, the safety of zinc supplementation in HIV-1 infection, is not clear. It is important to assess the virologic and immunologic consequences of zinc for replication of the HIV virus before mass zinc supplementation programmes are implemented, particularly in areas with high HIV-1 prevalence.

Objective. This study was a trial of zinc supplementation in HIV-1-infected children that aimed to assess the effect on plasma HIV-1 viral load and infectious disease morbidity.

Methods. This was a randomised double-blind placebo-controlled equivalence trial of zinc supplementation carried out at Grey’s hospital, an urban, tertiary-care center in Pietermaritzburg, South Africa. Ninety six children with HIV-1 infection were randomly assigned to receive 10 mg of elemental zinc as sulphate or placebo every day for 6 months. Both the zinc and placebo were produced by Nutriset and provided in blister packets of 14 tablets. Enrolled children were assessed for two weeks prior to supplementation with of zinc or placebo for baseline measurements that included plasma HIV-1 viral load and percentage of CD4+ T lymphocytes. These measurements were repeated at 3, 6 and 9 months after the start of supplementation. Information obtained at enrolment included anthropometric measurements, medical and immunization history. In total, children were scheduled for ten study visits after enrolment, i.e. 2 assessment visits prior to supplementation, every 2 weeks for the first month, monthly for 5 months, and finally at 9 months. Study children who fell ill were encouraged to seek care at Grey’s hospital, and at each illness visit, a physical examination was conducted and a questionnaire filled documenting signs and symptoms of disease, diagnoses and treatment. In addition, a study officer or pediatrician surveyed neighbouring clinics to identify study children who sought care at another facility.

Results. The mean log10 HIV-1 viral load was 5.4 (S.D. 0.61) for the placebo group and 5.4 (SD 0.66) for the zinc-supplemented group 6 months after supplementation began (difference 0.00002, 95% CI -0.27 to 0.27). Three months after supplementation ended, these values were 5.5 (SD 0.77) and 5.4 (SD 0.61), a difference of 0.05 (CI -0.24 to 0.35). The mean percentage of CD4+ T lymphocytes and median haemoglobin concentrations were similar between the two groups after supplementation. In addition, children given zinc supplementation were nearly half as likely to get watery diarrhea than the placebo group (7.4% and 14.5% respectively; p=0.0001).

Conclusion. This study illustrates that the provision of zinc supplements to children with HIV-1 infection in South Africa for 6 months did not increase plasma HIV-1 viral loads, decrease the percentage of CD4+ T lymphocytes or reduce haemoglobin concentration or serious adverse effects. Zinc supplementation also reduced the proportion of clinic visits of children with watery diarrhea. In conclusion, the authors advocate for zinc supplementation as a simple and cost-effective intervention to reduce morbidity and mortality of children with HIV-1 infection.