Nutritional alterations associated with HIV infection.

Nutritional alterations are common in HIV infection. Early studies documented weight loss and protein depletion, a finding associated with body cell mass depletion in untreated patients. The application of highly active antiretroviral therapy has led to a decreased incidence of malnutrition, although altered body fat distribution and metabolic alterations, including hyperlipidemia and insulin resistance, are common sequelae. The development of malnutrition is multifactorial and occurs through changes in caloric intake, nutrient absorption, or energy expenditure. Clinically, malnutrition develops as a result of either starvation or cachexia. Other hormonal and endocrinologic alterations include hypercortisolemia and hypogonadism. The rationale for providing nutritional support to AIDS patients is based upon the assumptions that nutrition status can be improved and that such improvements have clinical benefits. The results of hypercaloric feeding studies, including the use of appetite stimulants, indicate that weight gain is possible but that the weight gained is predominantly fat. In contrast, anabolic agents and resistance training exercise have been shown to promote body cell mass repletion and skeletal muscle gain. Cytokine inhibitors also have been evaluated for the treatment of wasting in HIV infection. Development of combination therapies, preventive therapies, and efficient and cost-effective therapies are current tasks in the field.