Objective

Nearly, a third of obese individuals, termed metabolically benign obese, have a low burden of adiposity-related cardiometabolic abnormalities, whereas a substantial proportion of normal-weight individuals possess risk factors.

Methods

In cross-sectional analyses of 699 normal weight and 1,294 overweight/obese postmenopausal women enrolled in a nested case-control stroke study ancillary to the Women's Health Initiative Observational Study, we compared levels of adiponectin, leptin, and resistin among metabolically benign normal weight, at-risk normal weight, metabolically benign obese, and at-risk obese women using components of the ATP III definition of the metabolic syndrome (metabolically benign: ≤1 of the four components; at-risk phenotype: ≥2 components or diabetes).

Results

Overall, 382/699 normal-weight women (54.6%) and 328/1,194 overweight/obese women (27.5%) were metabolically benign. Among normal-weight women, at-risk women had higher leptin and lower adiponectin levels compared to metabolically benign women; multivariate-adjusted odds ratios were significant for having leptin (OR: 2.51; 95% CI: 1.28-5.01) and resistin (1.46; 1.03-2.07) in the top tertile and adiponectin in the bottom tertile (2.64; 1.81-3.84). Compared to metabolically benign overweight/obese women, at-risk obese women had higher odds of having leptin in the top tertile (1.62; 1.24-2.12) and adiponectin in the bottom tertile (2.78; 2.04-3.77).

Conclusions

Overall, metabolically benign overweight/obese women had an intermediate adipokine profile (between at-risk obese and metabolically benign normal-weight women), whereas at-risk normal-weight women had a less favorable profile compared to metabolically benign normal-weight women. As adiponectin was the only adipokine independent of BMI, it may be most likely to have a role in the etiological pathway of these phenotypes.

Objective

It is unclear why despite a comparable cardiometabolic risk profile, "metabolically benign" overweight/obese individuals show an elevated risk of cardiovascular disease compared to normal weight individuals.

Design and methods

In cross-sectional analyses, we compared levels of ectopic fat (epicardial, pericardial, and hepatic fat) and adipokines (leptin, soluble leptin receptor, and high molecular weight [HMW] adiponectin) among metabolically benign (MBO) and at-risk overweight/obese (ARO), and metabolically benign normal weight (MBNW) women, screened for the Kronos Early Estrogen Prevention Study. We defined "metabolically benign" with ≤ 1, and "at-risk" with ≥2 components of the metabolic syndrome.

Results

Compared to MBO women, ARO women had significantly elevated odds of being in the top tertile of epicardial fat (OR: 1.76, 95% CI: 1.04-2.99), hepatic fat (OR: 1.90, 95% CI:1.12-3.24) and leptin (OR: 2.15, 95% CI: 1.23-3.76), and the bottom tertile of HMW-adiponectin (OR: 2.90, 95% CI: 1.62-5.19). Compared to MBNW women, MBO women had significantly higher odds of being in the top tertile of epicardial fat (OR: 5.17, 95% CI: 3.22-8.29), pericardial fat (OR: 9.27, 95% CI: 5.52-15.56) and hepatic fat (OR: 2.72, 95% CI: 1.77-4.19) and the bottom tertile of HMW adiponectin levels (OR: 2.51, 95% CI: 1.60-3.94).

Conclusions

Levels of ectopic fat and the adverse adipokine profile increase on a continuum of BMI, suggesting that the metabolically benign phenotype may be a transient state.