Intrathoracic fat in HIV-infected patients

Background The impact of HIV infection or antiretroviral therapy on the intrathoracic fat compartment is unknown. Methods Consecutive clinically stable HIV-infected adult patients, irrespective of exposure to antiretroviral therapy, and non-HIV-infected healthy volunteers, both without clinical evidence of body fat changes consistent with lipodystrophy and adjusted for age, gender and body mass index, were recruited for this study. Thoracic and abdominal fat was assessed by computed tomography and compared between patients and controls. Results There were nine women (33%) and 18 men (67%) in each group. Nineteen patients (70%) had been taking antiretrovirals for a median of 8 months (interquartile range: 6-11). Among the HIV-infected patients, intrathoracic fat (median; interquartile range) did not differ significantly between treated (6.7 cm(2); 4.5-8.3 cm(2)) and untreated (6.9 cm(2); 5.7-10.9 cm(2)) individuals (P=0.288). However, intrathoracic fat content (median; interquartile range) was higher in HIV-infected patients (6.8 cm(2); 5.6-10.5 cm(2)) than in controls (5.6 cm(2); 3.9-6.7 cm(2)) (P=0.025). Intrathoracic fat was positively correlated with intra-abdominal fat both in patients (rho=0.6, P=0.002) and in controls (rho=0.7, P=0.004). Conclusion In HIV-infected adults without clinical evidence of lipodystrophy, intrathoracic fat content was higher than in healthy persons and positively correlated with intra-abdominal fat content.