Nutritional therapy for HIV-infected patients is shifting focus. Drug treatments designed to combat the HIV virus have improved, decreasing some nutritional problems, while bringing others to light.
As researchers from the Nutrition/Infection Unit in the Department of Public Health and Family Medicine at Tufts University School of Medicine describe in an editorial review and other research reports, new nutritional challenges in HIV/AIDS care have emerged.
The changes, according to Alice Tang, MS, PhD, assistant professor at Tufts University School of Medicine, and her colleagues, have resulted from the introduction of an advanced class of drugs called highly active antiretroviral therapy (HAART) over a decade ago.
In the past, the nutritional component of HIV/AIDS care was directed toward two major goals: supplying the vital nutrients that were often lost through poorly-functioning digestive tracts and minimizing weight loss. "The newer medications keep patients healthier overall, so we are not dealing with quite as much severe weight loss," says Tang. "Now we are able to concentrate more on determining the vitamin and mineral ('micronutrient') requirements of these patients and investigating potential therapeutic uses of supplements."
This is particularly important in the age of HAART, according to Tang, who has researched the role of antioxidants, like vitamin E, in HIV extensively. As it turns out, HAART medications, while controlling disease progression for many patients, may also increase oxidative stress. "Oxidative stress" refers to the state of imbalance that exists when chemically unstable by-products of metabolism exceed the body's capacity to quench them, either with its own natural antioxidants or with those obtained from the diet. The potential result of this imbalance is damage to cells and tissues. "Research efforts must focus on determining if this is, indeed, true. If so, what is the mechanism? Will dietary or supplemental antioxidants help?" asks Tang.
Another area of active research underway at Tufts and elsewhere relates to what Tang calls, "one of the most vexing issues facing HIV-positive individuals." In fat redistribution or lipodystrophy syndrome, "body fat changes may include fat loss under the skin (on the trunk, extremities, buttocks or face) and/or fat gain (in the abdomen, back of the neck or in the breasts)" explains Denise Jacobson, PhD, MPH, assistant professor at Tufts School of Medicine. Patients with this condition may also have abnormal metabolism of fat and/or sugar. Jacobson says, "we are still learning about these changes, some of which may be related to HAART."
Over the years, the Nutrition/Infection Unit, led by Sherwood Gorbach, MD, professor of medicine, and Christine Wanke, MD, professor of medicine, has been active in nutrition and HIV research. In the current paper, which is just one of Tang's several reviews analyzing the research in the field, she summarizes the findings of studies looking at the roles of vitamins B12, A, and E in HIV transmission and disease progression. Results are mixed and inconclusive, but Tang says that these findings help to guide researchers in future endeavors. She says, "it is clear that micronutrients play a critical role in the maintenance of immune function and overall metabolism. We need to concentrate on defining the areas in which they may help to maximize the health status of HIV-infected patients."