Intermuscular and subcutaneous adipose tissue distributions differ in HIV+ versus HIV-men and women

BACKGROUND: Loss of subcutaneous (SAT) with sparing of visceral (VAT) adipose tissue (AT) has been documented in HIV + men and women. Intermuscular AT (IMAT) rivals VAT in independent associations with cardiovascular risk. OBJECTIVE: To determine whether the size and distribution of IMAT differs in HIV+ vs. HIV- men and/or women. DESIGN: We used whole-body MRI to measure VAT, IMAT and four SAT compartments and compared them by HIV status using whole-body skeletal muscle (SM) or total AT (TAT) as co-variates in multi-ethnic groups of healthy HIV- (n=86) and stable HIV+ (n=76) men and women. RESULTS: The sizes of AT depots (adjusting for SM) did not differ by HIV status, except for smaller gluteal SAT (lower trunk, between L(4)-L(5) to greater trochanter) in both sexes (P<0.05). The AT distribution (adjusting for TAT) was significantly different, with larger VAT (P<0.05) and smaller gluteal and limb SAT (P<0.05) in both HIV+ sexes; IMAT increased more with TAT in HIV+ vs. HIV- men (P<0.05 for slope interaction) but there were no significant differences in women. There were significant race by HIV interactions in AT distribution with more pronounced VAT differences in non-Hispanic white men and larger trunk SAT in African Americans HIV+ vs. HIV-. CONCLUSION: The AT distribution differed markedly in HIV+ vs. HIV- with limb and lower body SAT representing a smaller proportion of TAT in HIV+ in both sexes and IMAT representing a larger proportion of TAT in HIV+ vs. HIV- men.