Weight gain within six months of starting antiretroviral therapy resulted in better survival and improved clinical outcomes, in particular among the most severely malnourished, at district clinics in Lusaka, Zambia, John R. Koethe and colleagues reported in a study published in the April 1 online edition of the Journal of Acquired Immune Deficiency Syndromes.
The provision of antiretroviral therapy in sub-Saharan Africa since 2003 has significantly improved the lives of many. However, malnutrition in those areas where both high HIV prevalence and food shortages are epidemic makes care difficult.
The World Health Organization (WHO) classifies malnutrition according to body mass index (BMI). BMI is calculated as weight in kilogrammes divided by height in metres squared: mild (17.00 to 8.49), moderate (16.00 to 16.99), and severe (less than 16.00 kg/m2).
The authors cite analyses of patient outcomes in Zambia, Malawi and Tanzania which showed a low BMI (malnutrition) at the start of ART to be an independent predictor of early death.
However, little is known about the effect of improved nutrition on clinical outcomes. The authors note that this gap in the medical literature is significant as the benefits of early weight gain on clinical outcome would “serve as the theoretical foundation for food-by-prescription and food supplementation programmes in resource-constrained settings.”
Of the 46,159 patients starting ART at Lusaka district clinics from May 1, 2004 to April 30, 2008 the authors analysed data from 27,915 or 68% according to mild (more than 18.5 kg/m2), moderate (17.00 to 18.49 kg/m2), severe (16.00 to 16.99 kg/m2) and extremely severe malnutrition (less than 16.0 kg/m2)as indicated by BMI.
Inclusion criteria involved: a baseline BMI measurement; having remained active in the programme for six months; and a documented six-month weight measurement.
Death rates in the first 90 days were highest among those most severely malnourished (80 per 100 person-years; 95% CI: 74 to 86). After this point there was no real difference among the groups. This prompted the authors to perform further analyses based on baseline BMI findings.
However, a greater proportion of the most severely malnourished patients (39.2%) gained the most amount of weight (over 10 kilogrammes) as well as being least likely not to gain any weight over the six-month period.
Those who were mildly malnourished gained the least weight proportionally.
Failure to gain weight six months after the start of ART increased the chance of death ten fold when compared with those who had gained over ten kilogrammes.
In all categories weight gain of at least five kilogrammes meant better outcomes than no weight gain at all.
The authors noted that death is associated more with loss of lean body mass than with weight loss.
Their study, they added, did not look at body composition changes but weight gain, they note, probably included an increase in fat.
They suggest further studies are needed to look at the composition of weight gain after starting ART to better understand the link between survival and treatment outcome.
The study, the authors stress, was not intended to look at whether an improved food supply and a resulting weight gain play a part in the survival of severely malnourished patients, or whether weight gain after starting treatment is a marker of clinical response that occurs regardless of food intake.
Nonetheless, they note, their results do give support to programmes that provide food supplements to malnourished patients on ART.
Yet, they conclude, “given the expense, logistical barriers, and overlapping implications for health policy and economic development, further large controlled studies of supplementary feeding at ART initiation are warranted to improve programme success in resource-constrained settings.”