Insulin resistance, hepatic lipid and adipose tissue distribution in HIV-infected men.
BACKGROUND
A large proportion of HIV-infected patients on antiretroviral medication develop insulin resistance, especially in the context of fat redistribution. This study investigates the interrelationships among fat distribution, hepatic lipid content, and insulin resistance in HIV-infected men.


METHODS
We performed a cross-sectional analysis of baseline data from 23 HIV-infected participants in three prospective clinical studies. Magnetic resonance spectroscopy was used to quantify hepatic lipid concentrations. Magnetic resonance imaging was used to quantify whole-body adipose tissue compartments: that is, subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes, as well as the intermuscular adipose tissue (IMAT) subcompartment and the omental-mesenteric adipose tissue (OMAT) and retroperitoneal adipose tissue (RPAT) subcompartments of VAT. The homeostasis model for assessment of insulin resistance (HOMA-IR) was calculated from fasting glucose and insulin concentrations.


RESULTS
Hepatic lipid content correlated significantly with total VAT (r = 0.62, P = 0.0014), but not with SAT (r = 0.053, P = 0.81). In univariate analysis, hepatic lipid content was associated with the OMAT (r = 0.67, P = 0.0004) and RPAT (r = 0.53, P = 0.009) subcompartments; HOMA-IR correlated with both VAT and hepatic lipid contents (r = 0.61, P = 0.057 and r = 0.68, P = 0.0012, respectively). In stepwise linear regression models, hepatic lipid had the strongest associations with OMAT and with HOMA-IR.


CONCLUSIONS
Hepatic lipid content is associated with VAT volume, especially the OMAT subcompartment, in HIV-infected men. Hepatic lipid content is associated with insulin resistance in HIV-infected men. Hepatic lipid content might mediate the relationship between VAT and insulin resistance among treated, HIV-infected men.
He
Qing
Q
Division of Gastroenterology, Department of Medicine, St. Luke's-Roosevelt Hospital Center, Columbia University, New York, NY, USA.
Engelson
Ellen S
ES
Ionescu
Gabriel
G
Glesby
Marshall J
MJ
Albu
Jeanine B
JB
Kotler
Donald P
DP
D050154:Adiposity; D000328:Adult; D044966:Anti-Retroviral Agents / Q000009:adverse effects*; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects; D001786:Blood Glucose / Q000187:drug effects; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D050356:Lipid Metabolism / Q000187:drug effects*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D050151:Subcutaneous Fat / Q000187:drug effects / Q000378:metabolism; D016896:Treatment Outcome
D044966:Anti-Retroviral Agents; D001786:Blood Glucose; D007328:Insulin