The relationship between antiretroviral treatment of HIV infection, body fat distribution, insulin resistance, very low density lipoprotein (VLDL) and intermediate density lipoprotein (IDL) apolipoproteinB (apoB) kinetics was investigated in 55 HIV-infected patients taking two nucleoside analogs plus either a protease inhibitor (n = 15) or a non-nucleoside reverse transcriptase inhibitor (n = 25), 15 antiretroviral therapy-naïve patients and 12 HIV negative controls.

Compared with the controls HDL cholesterol was reduced in all groups (P < 0.01). Plasma triglyceride was increased in patients taking protease inhibitors (P < 0.05). VLDL and IDL apoB fractional catabolic rate (FCR) were lower in all treatment groups (P < 0.05) compared with controls. Trunk fat, VLDL apoB absolute secretion rate and insulin resistance were not different between groups. Peripheral fat was lower in the treated patients (P < 0.05) and correlated with duration of therapy (r = -0.55, P < 0.001). There was a positive correlation between peripheral fat and VLDL apoB FCR (P = 0.002) and IDL apoB FCR (P = 0.002) and negative correlation with VLDL apoB pool size, VLDL cholesterol and triglyceride (P < 0.03, P < 0.01, P < 0.002).

These results suggest that mild dyslipidaemia resulting from antiretroviral therapy is due to a decrease in VLDL and IDL apoB FCR which is associated with a loss of peripheral fat.