Evaluation of the effects of an instant soy and maize meal supplement on the vitamin A status of patients infected with the human immunodeficient virus

Abstract

The development of a culture sensitive nutritional supplement for people infected with the human immunodeficiency virus (HIV) in developing countries needs to be investigated by experts in the area of nutrition and dietetics. Evidence from studies has shown that nutrients (micronutrients and phytochemicals) have the potency to delay progression of HIV into acquired immunodeficiency syndrome (AIDS). The soybean is a locally available culturally accepted food within the Southern Africa region with a relatively adequate nutrition profile, complementing the staple food maize meal excellently. The bean is also a source of vitamin A, one of the nutrients that have been implicated to play a role in maintenance of an integral immune system. Little is understood of the effect of soybeans in HIV/AIDS disease progression. This placebo controlled trial was therefore implemented to assess the effect of an instant soy maize meal supplement (SMMS) in free living HIV-positive adults (n=16) in the North West Province in South Africa. The control group (n=12) took a placebo and a low-dose multivitamin tablet, while the intervention group took 300g daily of the SMMS and the multivitamin tablet. At baseline, midline (after three months), and end (after six months), assessments were performed on selected dietary nutrient intakes, anthropometric and biochemical variables and quality of life as measured by a validated questionnaire. In many cases the small numbers of subjects made it difficult to draw meaningful conclusions. At the end of the six months intervention the mean nutrient intakes of the SMMS group was increased by the supplement relative to that of the controls. The anthropometric measurements of both groups remained the same over six months. Markers for disease progression such as CD4 count and CD4 as percentage of total lymphocytes showed a decrease in the SMMS group (p<0.01 and p=0.05 respectively). Serum retinol levels were within the adequate range for both groups at baseline and end, though these levels tended to decline with a decrease in CD4 count. The SMMS group experienced a greater non-significant decrease in the mean serum retinol concentration at -1.2 µmol/L relative to - 0.04µmol/L for the control group. The

decrease in serum retinol binding protein was greater in the SMMS group at - 0.9mg/L (p=0.02) relative to the controls at -0.5mg/L (p=0.34). Quality of life improved in both groups (p=0.0005 in the control group). The SMMS group had started with higher scores than the control group, and the room for improvement was limited. Viral loads did not change significantly. The SMMS did not show any beneficial effect on the progression rate of HIV in this small group of subjects. However, the effect of the intervention might have been masked by the multivitamin tablet, which was taken by both groups. There is therefore a need for further research on the effect of SMMS with a bigger sample size. In anticipation of the relatively high withdrawal rate in studies with HIV/AIDS patients, at least double the number of subjects needed for detecting significant effects should be entered into such a trial. It is further recommended that the SMMS be fortified with vitamin A in quantities two to three times the recommended dietary allowance.