The association between different body mass index levels and midterm surgical revascularization outcomes

Abstract

Background There are conflicting results regarding the relationship between overweight/obesity and the outcomes of coronary artery bypass graft surgery (CABG), termed “the obesity paradox”. This study aimed to evaluate the effects of body mass index (BMI) on the midterm outcomes of CABG. Methods This historical cohort study included all patients who underwent isolated CABG at our center between 2007 and 2016. The patients were divided into five categories based on their preoperative BMIs (kg/m2): 18.5≤BMI<25, 25≤BMI<30, 30≤BMI<35, 35≤BMI<40, and BMI≥40. Patients with BMIs below 18.5 kg/m2 were excluded. The endpoints of this study were all-cause mortality and major adverse cardio-cerebrovascular events (MACCEs), comprising acute coronary syndromes, cerebrovascular accidents, and all-cause mortality at five years. For the assessment of the linearity of the relationship between continuous BMI and the outcomes, plots for time varying hazard ratio of BMI with outcomes were provided. Results Of 17 751 patients (BMI = 27.30 ±4.17 kg/m2) who underwent isolated CABG at our center, 17 602 patients (mean age = 61.16±9.47 y, 75.4% male) were included in this study. Multivariable analysis demonstrated that patients with pre-obesity and normal weight had similar outcomes, whereas patients with preoperative BMIs exceeding 30 kg/m2 kg/m2 had a significantly higher risk of 5-year all-cause mortality and 5-year MACCEs than those with pre-obesity. Additionally, a positive association existed between obesity degree and all-cause mortality and MACCEs. Further, BMIs of 40 kg/m2 or higher showed a trend toward higher MACCE risks (adjusted hazard ratio, 1.32; 95% confidence interval, 0.89 to 1.95), possibly due to the small sample size. A nonlinear, albeit negligible, association was also found between continuous BMI and the study endpoints. Conclusions Our findings suggest that preoperative obesity (BMI>30 kg/m2) in patients who survive early after CABG is associated with an increased risk of 5-year all-cause mortality and 5-year MACCEs. These findings indicate that physicians and cardiac surgeons should encourage patients with high BMIs to reduce weight for risk modification.

Assessing postoperative wound infection rates in ultrasound‐guided microwave ablation versus conventional surgery for varicose veins

“…The statistically significant difference in BMI between the groups undergoing UMA and conventional surgery prompts intriguing inquiries regarding patient selection and potential influence of BMI on treatment outcomes. This observation is consistent with the findings of Masoudkabir et al 19 who proposed that the BMI of an individual might impact the effectiveness and safety of surgical interventions. However, due to design of our study, the causal relationship between BMI and treatment outcomes cannot be determined conclusively; therefore, additional research is required in this area.…”

Body mass index effect on long-term survival after coronary artery bypass surgery: a competing risk analysis

“…Additionally, Schwann et al [ 11 ] identified a partial obesity paradox among overweight and mildly obese patients in a retrospective analysis of over 7000 CABG patients. On the other hand, Masoudkabir et al [ 17 ] highlighted obesity as an independent risk factor for worse outcomes, namely 5-year all-cause mortality and major adverse cardiac and cerebrovascular events in a 17 751 isolated CABG sample. Therefore, it seems unclear whether an obesity paradox exists after coronary surgery and how increasing body mass index (BMI) affects these patients' long-term survival.…”

BMI modifies HDL-C effects on coronary artery bypass grafting outcomes

“…A nonlinear, U-shaped correlation between BMI and mortality in patients with acute coronary syndrome (ACS) has been reported, exhibiting lower mortality in overweight or mild-moderate obese patients paradoxically [13,14]. However, some other studies have challenged this paradoxical U-shaped association [15].…”