An association between adiposity and serum levels of macrophage inflammatory protein-1α and soluble CD14 in HIV-infected adults: results from a cross-sectional study.

BACKGROUND

Greater adipose tissue is associated with increased circulating high-sensitivity C-reactive protein (hsCRP) levels in HIV-infected adults on antiretroviral therapy (ART), but the relationship between adiposity and other inflammation biomarkers is not well-characterized.

METHODS

We measured total and regional adipose tissue deposits using dual energy X-ray absorptiometry (DXA) and serum levels of interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α) receptor 1 and 2, macrophage inflammatory protein-1α (MIP-1α), macrophage chemotactic protein-1 (MCP-1), soluble CD14 and hsCRP in a cohort of adults on long-term ART. Regression models were adjusted for age, sex, CD4(+) T-cell count, smoking status, protease-inhibitor-use and daily use of either non-steroidal anti-inflammatory drugs or aspirin.

RESULTS

The majority (77%) of the 85 study participants were male, median CD4(+) T-cell count was 500 cells/μl (IQR 315-734) and median BMI was 25.1 kg/m(2) (IQR 22.7-28.1). DXA measurements of total fat mass were positively associated with serum hsCRP (β=1.82, P<0.01) and MIP-1α (β=1.36, P<0.01), but negatively associated with soluble CD14 (β=0.90, P<0.01). Results were similar for trunk fat, limb fat and serum leptin level. The positive relationship between DXA measurements and TNF-α receptor 1 approached significance (P≤0.07 for all). There was no consistent relationship between adiposity and serum IL-6, TNF-α receptor 2 or MCP-1 levels.

CONCLUSIONS

Total and regional adiposity was associated with serum hsCRP, but not other inflammatory cytokines shown to predict morbidity and mortality in treated HIV. Greater adiposity is associated with higher MIP-1α and lower soluble CD14 levels, possibly reflecting an important role for cells of the monocyte/macrophage lineage.