CSB versus fortified spread in wasted HIV infected adults in Malawi

Summary of published research¹

Eating ready-to-use fortified spread in Malawi

The prevalence of wasting, defined as a Body Mass Index (BMI) <18.5, in adults with advanced HIV infection in sub-Saharan Africa is 20-40%. Because food insecurity is common in sub-Saharan Africa, and an adequate diet is believed to be important for adherence to antiretroviral (ARV) therapy, supplementary feeding in conjunction with treatment is advocated as standard in the care of wasted adults with HIV in Malawi. Evidence to support the effectiveness of this practice however is limited, and there have been no published controlled trials showing the benefit of such food supplementation in settings with limited resources, whether people are receiving ARV therapy or not. The most commonly available supplementary food in food aid programmes is corn-soy blended flour (CSB). CSB, however, has been associated with disappointing results in supplementary feeding programmes among children, pregnant women and adults with HIV in sub-Saharan Africa. Specialised, energy dense ready-to-use fortified spreads1 have also been recommended for feeding wasted adults with HIV. A fortified spread has been formulated to deliver the same nutrients as the milk-based therapeutic food F-100 for severely malnourished children, and its use has been associated with better outcomes in therapeutic and supplementary feeding of malnourished children with and without HIV.

A recent study set out to investigate the effect of CSB versus a fortified spread on BMI in wasted Malawian adults with HIV who were starting ARV therapy. The study was a randomised, investigator blinded, controlled trial in a large, public clinic associated with a referral hospital in Blantyre Malawi.

A total of 491 adults with a BMI <18.5 participated in the study. The two groups were fed either ready-to-use fortified spread (n=245) or CSB (n=246). The main outcomes measured were changes in BMI and fat-free body mass after 3.5 months. Secondary outcomes were survival, CD4 count, HIV viral load, quality of life and adherence to ARV therapy.

Cooking CSB porridge

The mean BMI at enrolment was 16.5. After 14 weeks, patients receiving fortified spread had a greater increase in BMI and fat-free body mass than those receiving corn-soy blend: 2.2 (SD 1.9) vs 1.7 (SD 1.6) (difference 0.5, 95% confidence interval 0.2-0.8), and 2.9 (SD 3.2) vs 2.2 (SD 3.0) kg (difference 0.7 kg, 0.2 to 1.2 kg) respectively. The mortality rate was 27% for those receiving fortified spread and 26% for those receiving CSB. No significant differences in the CD4 count, HIV viral load, assessment of quality of life, or adherence to antiretroviral therapy were noted between the two groups.

One study limitation was that food consumption was not observed in either of the groups, so that it was not possible to know the degree of adherence with the dietary recommendations. Also, there was no control group so that it was impossible to know what the nutritional status would have been without supplementary feeding. A control group was included in the original proposal but this was deemed unethical by the review board in Malawi, as it is national policy to give supplementary food to wasted patients with HIV/AIDS.

The authors concluded that supplementary feeding with fortified spread resulted in a greater increase in BMI and lean body mass than feeding with CSB. However, the authors note that the CSB provided in the study cost $5.40 per patients per month, while fortified spread was three times as expensive at $16. Formal cost benefit analyses are required to determine whether supplementary feeding strategies are cost effective when compared with other elements of clinical care given to those with HIV in sub-Saharan Africa.

¹MacDonald. N et al (2009). Supplementary feeding with either ready-to-use fortified spread or con-soy blend in wasted adults starting antiretroviral therapy in Malawi: randomised, investigator blinded, controlled trial. British Medical Journal 2009;338:b1867 dol:10.1136/bmj.b1867

²Also referred to as Ready to Use Therapeutic Foods (RUTF)