Malnutrition at the time antiretroviral therapy is started is associated with significantly poorer survival, according to a study published in the July edition of HIV Medicine. In a retrospective study conducted in Singapore, investigators found that patients who were malnourished when they initiated potent HIV therapy had a six-fold increase in the risk of death compared to patients with good nutritional status. However, CD4 cell recovery was comparable between malnourished and well-nourished patients, and the investigators speculate that the increased mortality seen in patients with malnourishment could have been due to factors such as poorer drug absorption, inability to tolerate treatment, or lower physical functioning. They recommend that nutritional support should be provided to malnourished patients when anti-HIV treatment is started to reducing the risk of death.
An association between malnourishment and poorer prognosis in HIV-positive individuals was well described in the period before anti-HIV treatment became available. Even in the era of potent antiretroviral therapy, the unintentional loss of just 3% of body weight is associated with poorer survival. It is possible that malnourishment at the time anti-HIV treatment is started could result in poorer recovery of immune function, meaning that patients are vulnerable to opportunistic infections for longer. No studies have previously investigated this connection, so researchers in Singapore conducted a retrospective analysis of the medical records of 394 HIV-positive individuals who started any form of antiretroviral therapy from 1991 to 2000 with a CD4 cell count of 250 cells/mm3 or less.
Nutritional status was defined by calculating a patient’s body mass index (BMI). If an individual had a BMI below 17 kg/m2 they were defined as being malnourished.
Patients were followed for a median of 2.4 years. A total of 79 individuals died during follow-up and median duration of survival was a little over five years. Median BMI was 20kg/m2 and 16% of patients were moderately to severely malnourished when they started HIV treatment.
Three factors were identified by the investigators as being associated with poorer survival after the initiation of HIV therapy: an AIDS diagnosis (p = 0.14); taking monotherapy or dual antiretroviral therapy as opposed to potent three drug HIV treatment (p = 0.03); and, malnutrition (p = 0.004). In the period 1991 – 2000, malnourished patients had a hazard ratio of death of 2.19 compared to well nourished patients. When the investigators restricted their analysis to the 136 individuals who took potent antiretroviral therapy, they found that patients with malnutrition had a six-fold increase of death (hazard ratio 6.14, p = 0.01) compared to patients with good nutrition.
Data on CD4 cell count six months after the initiation of HIV therapy were available for 330 patients. The median increase in CD4 cell count was 64 cells/mm3 and there was no significant difference in the increase seen in patients with or without malnutrition.
“We found that malnutrition was significantly associated with reduced survival in patients commencing antiretroviral therapy”, write the investigators, who stress, “for patients starting antiretroviral therapy with moderate to severe malnutrition, the hazard ratio of death was doubled overall. For patients who commence HAART, the hazard ratio for those with moderate to severe malnutrition was six-fold higher than for those with normal nutritional status.”
As recovery of CD4 cell count was similar between patients with good nutritional status and malnourishment, the investigators suggest that factors such as poorer drug absorption, reduced ability to tolerate side-effects, and decreased physical function which can accompany malnourishment.
Mortality amongst individuals initiating HIV therapy could, the investigators suggest, be reduced by providing nutritional support to malnourished patients. They call for randomised controlled trials to conducted to determine the optimum nutritional support for patients starting HIV therapy.
Paton NI et al. The impact of malnutrition on survival and the CD4 cell response in HIV-infected patients starting antiretroviral therapy. HIV Medicine 7: 323 – 330, 2006.