Growth Velocity, Fat-Free Mass and Energy Intake Are Inversely Related to Viral Load in HIV-Infected Children

Abstract
The study objectives were to assess the relationships among human immunodeficiency virus (HIV) replication, energy balance, body composition and growth in children with HIV-associated growth failure (GF). Energy intake and expenditure, body composition and level of HIV RNA were measured in 16 HIV-infected children with growth failure (HIV+/GF+), defined as a 12-mo height velocity ≤ 5th percentile for age, and 26 HIV-infected children with normal rates of growth (HIV+/GF−). Energy intake was measured by repeated 24-h dietary recall, resting energy expenditure (REE) by indirect calorimetry and total energy expenditure (TEE) by the doubly labeled water method. Fat-free mass (FFM) was determined by dual X-ray energy absorptiometry and plasma HIV RNA by the polymerase chain reaction method. The mean plasma HIV RNA content among the HIV+/GF+ group was nearly 1.5 log higher than that of the HIV+/GF− group (4.89 ± 1.08 vs. 3.43 ± 1.64 ×102 copies/L, P = 0.009). The mean daily energy intake, and age-adjusted REE and TEE were lower in HIV+/GF+ children (P = 0.003, 0.06 and 0.16, respectively). HIV+/GF+ children had a mean daily energy deficit of 674 ± 732 kJ/d compared with HIV+/GF− children who had a mean energy surplus of 1448 ± 515 kJ/d (P = 0.030). There were no differences in REE after adjustment for differences in FFM and age using multiple regression analysis (P = 0.88). There was a significant inverse relationship between FFM and plasma HIV RNA [R2 = 0.64, standard error of the estimate (SEE) = 3.23] and between viral load and 12-mo growth velocity (R2 = 0.61, SE = 1.51). Viral load and energy intake were also inversely related (R2 = 0.17, SEE = 573.2, P = 0.0125). In HIV-infected children, rate of growth, quantity of FFM and energy intake are closely related to the level of HIV replication. The energy intake of children with HIV-associated GF may not be adequate for supporting normal development of FFM and growth, despite possible decreases in total energy expenditure.