Biomarker evaluation as a potential cause of gender differences in obesity paradox among patients with STEMI

Obesity with its worldwide growing prevalence is an established cardiovascular risk factor with increased morbidity and mortality. However, the phenomenon, that mild to moderate obesity seems to represent a protective effect on diseases has been termed the "obesity paradox".

We retrospectively assessed 529 patients (72.6% male, mean age 59.7±12.7years) admitted with ST-elevation myocardial infarction (STEMI). The female and male study populations were separated into four body mass index (BMI) groups: ≤24.9kg/m(2), 25.0-29.9kg/m(2), 30.0-34.9kg/m(2) and ≥35.0kg/m(2). Blood samples of high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c) were analyzed.

With increasing BMI group the rate of major adverse cardiac events (MACE) decreased in all patients (test for trend p=0.041). No gender difference between MACE and BMI could be noticed (p=0.16). A higher risk for MACE was indicated in group BMI ≤18.5kg/m(2) in comparison to group BMI 25.0-29.9kg/m(2) (OR: 7.93; 95% CI: 1.75-35.89; p=0.0091), whereas group BMI 30.0-34.9kg/m(2) was significant associated with a lower risk in comparison to group BMI 25.0-29.9kg/m(2) (OR: 0.65; 95% CI: 0.21-1.96; p=0.044). An association between HDL-c (p=0.55) or LDL-c (p=0.10) and MACE could not be detected.

The study demonstrates that patients with STEMI and a BMI of 30.0-34.9kg/m(2) have a decreased risk for MACE compared to patients with normal BMI. No gender related differences were indicated. An association between MACE and lipoproteins could not be detected.