The Association of Body Mass Index with Outcomes after Carotid Endarterectomy

High body mass index is associated with elevated risk of perioperative ischemic stroke in patients who underwent noncardiac surgery: A retrospective cohort study

BACKGROUND

Body mass index (BMI) serves as a global metric for assessing obesity and overall health status. However, the impact of BMI, treated as a continuous variable, on the risk of perioperative stroke remains poorly understood. This retrospective cohort study aimed to elucidate the association between BMI and the risk of perioperative ischemic stroke in patients undergoing non-cardiovascular surgery.

METHODS

A cohort of 223,415 patients undergoing noncardiac surgery at the First Medical Center of Chinese PLA General Hospital between January 1, 2008 and August 31, 2019 was screened. Preoperative high BMI, defined as BMI >22.64 kg/m2, was the primary exposure, and the outcome of interest was the new diagnosis of perioperative ischemic stroke within 30 days post-surgery. Robust controls for patient and intraoperative factors were implemented to minimize residual confounding. Logistic regression and propensity score matching were employed, and patients were stratified into subgroups for further investigation.

RESULTS

The overall incidence of perioperative ischemic stroke was 0.23% (n = 525) in the cohort. After adjusting for patient-related variables (OR 1.283; 95% CI, 1.04-1.594; p < 0.05), surgery-related variables (OR 1.484; 95% CI, 1.2-1.849; p < 0.001), and all confounding variables (OR 1.279; 95% CI, 1.025-1.607; p < 0.05), patients with BMI >22.64 kg/m2 exhibited a significantly increased risk of perioperative ischemic stroke. This association persisted in the propensity score matched cohort (OR 1.577; 95% CI, 1.203-2.073; p < 0.01). Subgroup analyses indicated that preoperative BMI >22.64 kg/m2 correlated with an elevated risk of perioperative ischemic stroke in female patients, those with coronary heart disease, peripheral vascular diseases, and individuals undergoing neurosurgery.

CONCLUSION

We first identified BMI >22.64 kg/m2 as a substantial and independent risk factor for perioperative ischemic stroke in Chinese noncardiac surgery patients. Normal BMI may not suffice as a universal preventive standard. Instead, a more stringent perioperative weight management approach is recommended, particularly for specific subgroups such as female patients, those with coronary heart disease and peripheral vascular disease, and individuals scheduled for neurosurgery.

Transcarotid revascularization in obese patients

OBJECTIVE

Transcarotid revascularization (TCAR) is a minimally invasive hybrid surgical carotid stenting technique which utilizes cerebral flow reversal as embolic protection during carotid lesion manipulation. This investigation was performed to define the perioperative risks associated with this operation in the obese patient.

METHODS

A retrospective review of tandem carotid revascularization databases maintained at two high-volume health systems was performed to capture all TCARs performed between 2015 and 2022. A threshold of body mass index of 35 kg/m2 defined the "obese" patient. Demographics, intraoperative, perioperative, and follow-up characteristics were compared using univariate analysis.

RESULTS

We performed 793 TCAR procedures that qualified for study inclusion within the prespecified time. After applying our obesity definition, 129 patients qualified as obese and were compared to the remainder. There were no significant differences in baseline demographics as comparable Charlson Comorbidity Indices were noted between groups; however, obese patients had a significantly higher prevalence of hypertension, hyperlipidemia, and diabetes. Intraoperative, case complexity in the obese patients did not seem to be increased, as measured by operative time (68.4 ± 23.0 vs 64.2 ± 25.8 min, p = 0.09), fluoroscopic time (4.9 ± 3.2 vs 4.6 ± 3.6 min, p = 0.38), and estimated blood loss (40.6 ± 49.0 vs 46.6 ± 49.4 min, p = 0.22). Similarly, no disparities were observed with respect to ipsilateral stroke (3.1 vs. 1.7%, p = 0.29), contralateral stroke (0 vs. 0.2%, p > 0.99), death (0 vs. 1.1%, p = 0.61), and stroke/death (3.1 vs. 3.0%, p > 0.99) in the 30-day perioperative period. Both cohorts were followed for approximately 1 year (12.0 ± 13.4 vs 11.6 ± 13.4 months, p = 0.76). During this period, rates of ipsilateral stroke (3.1% vs. 2.7%, p > 0.99), contralateral stroke (1.1 vs. 0.8%, p > 0.99), and death (4.7 vs. 6.2%, p = 0.68) were similar.

CONCLUSIONS

TCAR performed in the obese population was not more challenging by intraoperative characteristics and did not result in a statistically higher incidence of adverse events in the perioperative phase.

Body Mass Index and Late Adverse Outcomes after a Carotid Endarterectomy

A cohort study was conducted to examine the association of an increased body mass index (BMI) with late adverse outcomes after a carotid endarterectomy (CEA). It comprised 1597 CEAs, performed in 1533 patients at the Vascular Surgery Clinic in Belgrade, from 1 January 2012 to 31 December 2017. The follow-up lasted four years after CEA. Data for late myocardial infarction and stroke were available for 1223 CEAs, data for death for 1305 CEAs, and data for restenosis for 1162 CEAs. Logistic and Cox regressions were used in the analysis. The CEAs in patients who were overweight and obese were separately compared with the CEAs in patients with a normal weight. Out of 1223 CEAs, 413 (33.8%) were performed in patients with a normal weight, 583 (47.7%) in patients who were overweight, and 220 (18.0%) in patients who were obese. According to the logistic regression analysis, the compared groups did not significantly differ in the frequency of myocardial infarction, stroke, and death, as late major adverse outcomes (MAOs), or in the frequency of restenosis. According to the Cox and logistic regression analyses, BMI was neither a predictor for late MAOs, analyzed separately or all together, nor for restenosis. In conclusion, being overweight and being obese were not related to the occurrence of late adverse outcomes after a carotid endarterectomy.

Body mass index and early outcomes after carotid endarterectomy

As the existing data on the correlation of adiposity with adverse outcomes of carotid endarterectomy (CEA) are inconsistent, the aim of the present study is to examine the correlation of an increased body mass index with 30-day complications after carotid endarterectomy. The cohort study comprises 1586 CEAs, performed at the Clinic for Vascular Surgery in Belgrade, from 2012-2017. Out of them, 550 CEAs were performed in patients with normal body mass index (18.5-24.9), 750 in overweight (25.0-29.9), and 286 in obese (≥30) patients. The association of overweight and obesity with early outcomes of carotid endarterectomy was assessed using univariate and multivariate logistic regression analysis. Overweight patients, in whom CEAs were performed, were significantly more frequently males, compared to normal weight patients-Odds Ratio (OR) 1.51 (95% confidence interval- 1.19-1.89). Moreover, overweight patients significantly more frequently had non-insulin-dependent diabetes mellitus-OR 1.44 (1.09-1.90), and more frequently used ACEI in hospital discharge therapy-OR 1.41 (1.07-1.84) than normal weight patients. Additionally, the CEAs in them were less frequently followed by bleedings-OR 0.37 (0.16-0.83). Compared to normal weight patients, obese patients were significantly younger-OR 0.98 (0.96-0.99), and with insulin-dependent and non-insulin-dependent diabetes mellitus-OR 1.83 (1.09-3.06) and OR 2.13 (1.50-3.01) respectively. They also more frequently had increased triglyceride levels-OR 1.36 (1.01-1.83), and more frequently used oral anticoagulants in therapy before the surgery-OR 2.16 (1.11-4.19). According to the results obtained, overweight and obesity were not associated with an increased death rate, transient ischemic attack (TIA), stroke, myocardial infarction, or with minor complications, and the need for reoperation after carotid endarterectomy. The only exception was bleeding, which was significantly less frequent after CEA in overweight compared to normal weight patients.

Preoperative Evaluation and Cardiac Risk Assessment in Vascular Surgery

We summarize epidemiologic trends, outcomes, and preoperative guidelines for vascular surgery patients from 2010 to 2022. Vascular surgery continues to evolve in technology and engineering to treat a surgical population that suffers from a high prevalence of comorbidities. Preoperative optimization seeks to characterize the burden of disease and to achieve medical control in the timeline available before surgery. Risk assessment, evaluation, optimization, and prediction of major adverse cardiac events is an evolving science where the Vascular Surgery Quality Initiative has made an impact. Ongoing investigation may demonstrate value for preoperative echocardiography, functional capacity, frailty, and mobility assessments.

Association between Masseter Muscle Area and Thickness and Outcome after Carotid Endarterectomy: A Retrospective Cohort Study

Low muscle mass is associated with adverse outcomes after surgery. This study examined whether facial muscles, such as the masseter muscle, could be used as a proxy for generalized low muscle mass and could be associated with deviant outcomes after carotid endarterectomy (CEA). As a part of the Vascular Ageing study, patients with an available preoperative CT-scan, who underwent an elective CEA between December 2009 and May 2018, were included. Bilateral masseter muscle area and thickness were measured on preoperative CT scans. A masseter muscle area or thickness of one standard deviation below the sex-based mean was considered low masseter muscle area (LMA) or low masseter muscle thickness (LMT). Of the 123 included patients (73.3% men; mean age 68 (9.7) years), 22 (17.9%) patients had LMA, and 18 (14.6%) patients had LMT. A total of 41 (33.3%) patients had a complicated postoperative course and median length of hospital stay was four (4–5) days. Recurrent stroke within 5 years occurred in eight (6.6%) patients. Univariable analysis showed an association between LMA, complications and prolonged hospital stay. LMT was associated with a prolonged hospital stay (OR 8.78 [1.15–66.85]; p = 0.036) and recurrent stroke within 5 years (HR 12.40 [1.83–84.09]; p = 0.010) in multivariable logistic regression analysis. Masseter muscle might be useful in preoperative risk assessment for adverse short- and long-term postoperative outcomes.