High-molecular weight adiponectin/HOMA-IR ratio as a biomarker of metabolic syndrome in urban multiethnic Brazilian subjects

<div><p>Metabolic syndrome (MetS) has an important epidemiological relevance due to its increasing prevalence and association with type 2 diabetes and cardiovascular disease. Insulin resistance is a core feature of the MetS. HOMA-IR is a robust clinical and epidemiological marker of MetS. Adiponectin is an adipokine with insulin-sensitizing and anti-inflammatory functions; its levels decrease as number of components of MetS increases. High-molecular weight adiponectin (HMWA) is the multimer responsible for the relationship of adiponectin with insulin sensitivity. HOMA-IR and HMWA are suitable candidates for MetS biomarkers. The ratio of adiponectin to HOMA-IR has been validated as a powerful index of MetS and considered a better marker of its presence, than either HOMA-IR or adiponectin alone, in selected homogeneous populations. We compared the strength of association between HMWA, HOMA-IR and HMWA/HOMA-IR ratio with MetS and its key components. Our data have shown that the median (25^th, 75^th percentile) of HMWA/HOMA-IR ratio was lower in subjects with MetS [0.51 (0.33, 1.31)] as compared to those without it [2.19 (1.13, 4.71)]. The correlation coefficient (r) was significantly higher for HMWA/HOMA-IR ratio as compared to HMWA for waist circumference (-0.65; -0.40, respectively); mean blood pressure (-0.27; -0.14, respectively); fasting glucose (-0.38; -0.19, respectively); HDL-cholesterol (0.44; 0.40, respectively); and triglycerides (-0.35; -0.18, respectively). In a multivariable logistic regression analysis, the HMWA/HOMA-IR ratio was a sensitive predictor for MetS, being the only marker that was significantly associated with each and all the individual components of the syndrome. These results expand on previous studies in that we used the active circulating form of adiponectin, i.e. HMWA, and represent a typical Brazilian cohort characterized by intense interethnic admixture. Thus, the HMWA/HOMA-IR ratio is a minimally invasive biomarker for MetS that could be clinically useful in prognosing patient outcome.</p></div

Cardiometabolic variables in subjects with and without metabolic syndrome.

<p>Cardiometabolic variables in subjects with and without metabolic syndrome.</p

Partial correlations^* between HMWA, HOMA-IR and the HMWA/HOMA-IR ratio with cardiometabolic variables.

<p>Partial correlations^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180947#t003fn001" target="_blank">*</a>} between HMWA, HOMA-IR and the HMWA/HOMA-IR ratio with cardiometabolic variables.</p

Comparison of predicting powers between HMWA, HOMA-IR and HMWA/HOMA-IR ratio for metabolic syndrome.

<p>HMWA, high molecular weight adiponectin; HOMA-IR, homeostatic model assessment of insulin resistance; ROC, receiver operating characteristic; AUC, area under the curve.</p

Clinical and laboratory characteristics of the study population.

<p>Clinical and laboratory characteristics of the study population.</p

Odds ratios (95% CI) for associations between MetS and HMWA, HOMA-IR and HMWA/HOMA-IR ratio.

<p>Odds ratios (95% CI) for associations between MetS and HMWA, HOMA-IR and HMWA/HOMA-IR ratio.</p

Odds ratios^* (95% CI) and ROC curves analysis for the association between each component of MetS and HMWA, HOMA-IR and HMWA/HOMA-IR ratio.

<p>Odds ratios^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180947#t005fn001" target="_blank">*</a>} (95% CI) and ROC curves analysis for the association between each component of MetS and HMWA, HOMA-IR and HMWA/HOMA-IR ratio.</p