Key result
Class I obesity shows no independent protection against 1-year major cardiovascular events after multivariate adjustment.
Why the study?
Despite obesity being linked to increased cardiovascular disease, studies have suggested an obesity paradox where overweight and mildly obese patients experience better outcomes, prompting this study to characterize the association between BMI and in-hospital and one-year outcomes.
Does mild obesity (the 'obesity paradox') improve clinical outcomes in patients with STEMI?
Cohort (n=2,397)
No
Does mild obesity (the 'obesity paradox') improve clinical outcomes in patients with STEMI?
This study suggests that the apparent 'obesity paradox' in STEMI survival is likely a statistical artifact driven by confounding variables such as age, rather than a genuine biological protective effect of mild obesity.
Answers are grounded in this paper and cite their sources.
Crude obesity paradox in STEMI vanishes after adjustment; should not change practice and leaves true relationship open.
BACKGROUND: Obesity is strongly associated with increased cardiovascular diseases (CVD) and cardiovascular risk factors, such as diabetes mellitus, hypertension, and dyslipidemia. However, numerous studies have suggested the existence of an "obesity paradox" in which overweight and mildly obese patients often exhibit a better outcome than their leaner counterparts. Therefore, this study aimed to characterize the association between BMI and in-hospital and one-year outcomes. METHOD: ) was classified into underweight (<18.5), normal weight (18.5-24.9), overweight (25-29.9), class I/mild obese (30-34.9), and class II/extreme obese (≥35) categories. The independent predictors of the in-hospital and one-year outcomes were assessed using multivariable logistic regression models. RESULTS: Out of the 2397 patients, 43 (1.79%) were underweight, 934 (38.97%) were normal, 1038 (43.30%) were overweight, 322 (13.43%) were class I obese, and 60 (2.50%) were class II obese. The results of the crude analysis showed that class I obesity was protective against CV death (OR 0.50; 95% CI 0.30-0.84), MACE3 (MI, stroke, and death) (OR 0.47; 95% CI 0.29-0.76), and MACE5 (MACE3 plus unstable angina and heart failure) (OR 0.59; 95% CI 0.44-0.79). CONCLUSIONS: Multivariate adjustment eliminated the protective effect of class I obesity against death and MACE events. Therefore, it is possible that this protective effect does not exist and instead reflects the impact of confounding variables such as age.
No takes yet. Share an insight, caveat, or question.
Sharbati et al. (2023) conducted a cohort in ST-segment elevation myocardial infarction (STEMI) (n=2,397). Class I obesity (BMI 30-34.9 kg/m2) vs. Normal weight (BMI 18.5-24.9 kg/m2) was evaluated on MACE3 (MI, stroke, and death) at one-year follow-up (Crude) (OR 0.47, 95% CI 0.29-0.76, p=0.001). Class I obesity showed a crude protective effect against 1-year MACE3, but this 'obesity paradox' was eliminated after multivariate adjustment, suggesting the protective effect reflects unmeasured confounding.
Synapse has enriched 8 closely related papers on similar clinical questions. Consider them for comparative context: