Risk of 5% weight loss increased in HAART era, not linked to lipodystrophy

The proportion of HIV-positive patients who experienced an unintentional loss in body weight of 5% or more increased significantly between 1995 and 2003, according to an American study published in the September 1^st edition of the Journal of Acquired Immune Deficiency Syndromes. The investigators found that this weight loss was not connected with lipodystrophy and express concern that weight loss of 5% or more has been shown to markedly increase the risk of death in HIV-positive patients.

Numerous studies have shown that the incidence of HIV-related wasting syndrome (defined as a 10% or greater loss in body weight) has declined markedly since effective anti-HIV therapy became available. However, a US study found that weight loss of 5% and wasting were still common in the era of potent HIV therapy and was associated with an increased risk of death.

In the light of these findings, investigators from the Nutrition for Healthy Living (NFHL) cohort wished to determine the incidence of, and risk factors for weight loss in the era of antiretroviral therapy.

A total of 713 individuals were recruited to the study. Every six months their weight, height and skinfold measurements were taken. Data were also obtained on three-day food intake, and resting calorie consumption. In addition, the investigators gathered information on health-related quality of life, clinical status, the use of anti-HIV medication, recreational drug use and an individual's possible intentions to lose weight in the previous six months.

Weight loss of 5% or more was seen in 377 individuals (53%) at a total of 589 study visits. Most of these patients (64%) had a 5% loss on one occasion only, although 3% presented with a loss of 5% of more in their body weight on four or more occasions.

In multivariate analysis, a history of ever using drugs (p = 0.002), living in poverty (p = 0.02), a CD4 cell count below 200 cells/mm³ (p = 0.02), a viral load above 100,000 copies/ml (p = 0.009), diarrhoea (p = 0.003), nausea (p

In addition, the investigators found that the risk of 5% or greater weight loss increased by approximately 5% (p = 0.01) with each six month period of calendar observation between 1995 and 2004. This relationship remained significant after controlling for drug use, poverty, obesity, low CD4 cell count, high viral load, diarrhoea, nausea and thrush.

“Despite the widespread use of HAART, we found that the risk of 5% or more weight loss over an average period of 6.5 months increased steadily between 1995 and 2003”, write the investigators. The investigators do not believe that these findings necessarily contradict the studies, which found a fall in the incidence of HIV-related wasting of 10% or more of body weight after the introduction of HAART. They explain, “our findings are not based on a clinical diagnosis of wasting syndrome but, instead, on actual weight measurements.” They add, “dramatic declines in weight, 10% or greater, are rarely seen anymore.”

The investigators tried to categorise the “look” of weight loss in the early and later years of the study to see if was associated with lipodystrophy. They found that there was no significant difference in mean weight, body mass index or skinfold measurements in patients recruited in the two periods of the study.

The proportion of patients categorised as overweight (body mass index above 25kg/m² increased from 30% in the pre-1997 to 35% in the later years of the study, however, even after adjusting for this the investigators still found that weight loss increased from 1997 onwards.

“We have found that the risk of 5% or greater unintentional weight loss over six-month intervals is on the rise in our cohort of HIV-infected participants...weight loss of this magnitude is associated with a significantly increased risk of mortality among HAART-treated-HIV-infected participants”, conclude the investigators. They add, “attention to weight loss in the current HIV climate, where patients are maintaining more normal clinical status, remains important.”