Obesity as an Independent Predictor of Outcome after Endovascular Abdominal Aortic Aneurysm Repair

Body mass index and the risk of abdominal aortic aneurysm presence and post-operative mortality: a systematic review and dose-response meta-analysis

BACKGROUND

The clinical data regarding the relationships between body mass index (BMI) and abdominal aortic aneurysm (AAA) are inconsistent, especially for the obese and overweight patients. The aims of this study were to determine whether obesity is associated with the presence of AAA and to investigate the quantitative relationship between BMI and the risk of AAA presence and post-operative mortality.

MATERIALS AND METHODS

PubMed, Web of Science and Embase databases were used to search for pertinent studies updated to December 2023. The pooled relative risk (RR) with 95% confidence interval (CI) was estimated by conventional meta-analysis based on random effects model. Dose-response meta-analyses using robust-error meta-regression (REMR) model were conducted to quantify the associations between BMI and AAA outcome variables. Subgroup analysis, sensitivity analysis and publication bias analysis were performed according to the characteristics of participants.

RESULTS

18 studies were included in our study. The meta-analysis showed a higher prevalence of AAA with a RR of 1.07 in patients with obesity. The dose-response meta-analysis revealed a non-linear relationship between BMI and the risk of AAA presence. A "U" shape curve reflecting the correlation between BMI and the risk of post-operative mortality in AAA patients was also uncovered, suggesting the "safest" BMI interval [28.55, 31.05] with the minimal RR.

CONCLUSIONS

Obesity is positively but nonlinearly correlated with the increased risk of AAA presence. BMI is related to AAA post-operative mortality in a "U" shaped curve, with the lowest RR observed among patients suffering from overweight and obesity. These findings offer a preventive strategy for AAA morbidity and provide guidance for improving the prognosis in patients undergone AAA surgical repair.

Japanese single-center experience of abdominal aortic aneurysm repair over 20 years: should open or endovascular aneurysm repair be performed first?

PURPOSE

The present study analyzed the outcomes of our experience with abdominal aortic aneurysm (AAA) repair over 20 years using endovascular aortic repair (EVAR) with commercially available devices or open aortic repair (OAR) and reviewed our surgical strategy for AAA.

METHODS

From 1999 to 2019, 1077 patients (659 OAR, 418 EVAR) underwent AAA repair. The OAR and EVAR groups were compared retrospectively, and a propensity matching analysis was performed.

RESULTS

EVAR was first introduced in 2008. Our strategy was changed to an EVAR-first strategy in 2010. Beginning in 2018, this EVAR-first strategy was changed to an OAR-first strategy. After propensity matching, the overall survival in the OAR group was significantly better than that in the EVAR group at 10 years (p = 0.006). Two late deaths due to AAA rupture were identified in the EVAR group, although there were no significant differences between the OAR and EVAR groups with regard to the freedom from AAA-related death at 10 years. The rate of freedom from aortic events at 10 years was significantly higher in the OAR group than in the EVAR group (p < 0.0001).

CONCLUSION

The rates of freedom from AAA-related death in both the OAR and EVAR groups were favorable, and the rate of freedom from aortic events was significantly lower in the EVAR group than in the OAR group. Close long-term follow-up after EVAR is mandatory.

Obesity is Not Associated with Adverse Perioperative or Poorer Clinical Outcomes following Thoracic and Fenestrated-Branched Endovascular Aortic Repair

BACKGROUND

Obesity is a risk factor for higher morbidity and mortality following open aortic repair but currently there is limited literature on its impact on clinical and procedural outcomes following thoracic endovascular aortic repair (TEVAR) and branched-fenestrated endovascular aortic repair (B-FEVAR).

METHODS

We conducted a retrospective case-control analysis of a prospectively collected nonrandomized database to evaluate the effects of obesity on procedural and clinical outcomes after B-FEVAR/TEVAR in treatment of pararenal/thoracoabdominal aortic aneurysm and dissection at the University hospital of Nantes (France) between January 2016 and December 2021. Patients were divided in 2 groups according to their body mass index (BMI) and the rate of technical success, complications (renal, pulmonary, cardiac, and neurological events), 30-day and long-term survival, freedom from target vessel instability and reintervention were compared.

RESULTS

195 patients were included (mean age 69.6 DS±11.2; n = 135, 69.2% men; mean BMI: 26.6 kg/m2 range 19-41) totalling n = 72 (36.8%) TEVAR, n = 107 (55.4%) FEVAR and n = 14 (7.3%) BEVAR. Patients were divided in 2 groups [obese: BMI≥30 kg/m2n = 52 (26.7%); and nonobese, BMI<30 kg/m2, n = 143 (73.3%) that statistically differed only in terms of coronary artery disease (obese 42.3% vs. 26.6% nonobese, P = 0.035) and diabetes (obese 25% vs. 12.6% nonobese, P = 0.03). No statistical differences were noted in primary technical (94.2% vs. 94.4%, P = 1.00) and clinical (92.3% vs. 95.1%, P = 0.49) success. Overall morbidity (30.8% vs. 21.1%, P = 0.16), visceral vessels instability (1.9% vs. 1.4% P = 1.00), reintervention rate within 30 days (9.6% vs. 5.6% P = 0.33), 90 days (7.7% vs. 9.8%, P = 0.78) and during follow-up (9.8% vs. 20%, P = 0.14) were comparable. No statistical difference were noted in 30-day mortality (3.8% vs. 4.9%, P = 1.00) and the 2-year follow-up survival (86.8% vs. 78.4%, P = 0.180) between the 2 groups.

CONCLUSIONS

In this series, obesity was not associated to worst clinical outcomes or higher mortality rate following TEVAR/B-FEVAR. However, considering our small patient sample, a conclusive analysis on obesity as risk factors for adverse events after endovascular treatment is not possible. A larger sample from the collaboration of multiple centers will be required to obtain definitive conclusions.

The impact of obesity on perioperative and postoperative outcomes after elective endovascular abdominal aortic aneurysm repair

BACKGROUND

Obesity is a common and growing health problem in vascular surgery patients, as it is in all patient groups. Evidence regarding body mass index (BMI) on endovascular aneurysm repair (EVAR) outcomes is not clear in the literature. We aimed to determine the impact of obesity on perioperative and midterm outcomes of elective EVAR between obese and non-obese patients.

METHODS

Under a retrospective study design, a total of 120 patients (109 males, 11 females, mean age: 74.45 ± 8.59 (53-92 years)) undergoing elective EVAR between June 2012 and May 2020 were reviewed. Patients were stratified into two groups: obese (defined as a body mass index (BMI) ≥ 30 kg/m²) and non-obese (mean BMI < 30 kg/m² (32.25 ± 1.07 kg/m² vs 25.85 ± 2.69 kg/m²)).

RESULTS

Of the 120 patients included in the study, 81 (67.5%) were defined as "nonobese," while 39 (32.5%) were obese. The mean BMI of the study group was 27.93 ± 3.78 kg/m². In obese patients, the procedure time, fluoroscopy time, and dose area product (DAP) values were longer than those of non-obese patients: 89.74 ± 20.54 vs 79.69 ± 28.77 min (p = 0.035), 33.23 ± 10.14 vs 38.17 ± 8.61 min (p = 0.01) and 133.69 ± 58.17 vs 232.56 ± 51.87 Gy.cm² (p < 0.001). Although there was no difference in sac shrinkage at 12-month follow-up, there was a significant decrease at 6-month follow-up in both groups (p = 0.017). Endoleak occurred in 17.9% (n = 7) of the obese group versus 11.1% (n = 9) of the non-obese group (p = 0.302). Iliac branch occlusion developed in four patients, 3 (3.7%) in the non-obese group and 1 (2.6%) in the obese group (p = 0.608). The all-cause mortality rate was slightly higher in the obese group; however, it did not differ between the groups (p = 0.463).

CONCLUSION

In addition to the longer procedure times, fluoroscopy times, and DAP values in obese patients, regardless of obesity, significant sac shrinkage in the first 6 months of follow-up was observed in both groups. No difference was documented with regards to mortality or morbidity following EVAR.

Association Between Obesity and Outcomes Following Endovascular Aneurysm Repair

BACKGROUND

Obesity is prevalent in patients with abdominal aortic aneurysms (AAA). There is an association between increasing body mass index (BMI) and increased overall cardiovascular mortality and morbidity. This study aims to assess the difference in mortality and complication rates between normal weight (NW), overweight (OW), and obese patients undergoing endovascular aneurysm repair (EVAR) for infrarenal AAA.

METHODS

This is a retrospective analysis of consecutive patients undergoing EVAR for AAA between January 1998 and December 2019. Weight classes were defined as: BMI<18.5 kg/m², underweight; BMI 18.5-24.9 kg/m², NW; BMI 25.0-29.9 kg/m², OW; BMI 30.0-39.9 kg/m², obese; BMI>39.9 kg/m² morbidly obese. Primary outcomes were long-term all-cause mortality and freedom from reintervention. Secondary outcome was aneurysm sac regression (defined as a reduction in sac diameter of 5 mm or more). Kaplan-Meier survival estimates and mixed model analysis of variance were used.

RESULTS

The study included 515 patients (83% males, mean age 77 ± 8 years) with a mean follow-up of 3.8 ± 2.8 years. In terms of weight class, 2.1% (n = 11) were underweight, 32.4% (167) were NW, 41.6% (n = 214) were OW, 21.2% (n = 109) were obese, and 2.7% (n = 14) were morbidly obese. Obese patients were younger (mean difference -5.0 years) but had a higher prevalence of diabetes mellitus (33.3% vs. 10.6% for NW) and dyslipidemia (82.4% vs. 60.9% for NW). Obese patients had similar freedom from all-cause mortality (88%) compared to OW (78%) and NW (81%) patients. The same findings were evident for freedom from reintervention where obese (79%) was similar to OW (76%) and NW (79%). At a mean follow-up of 5.1 ± 0.4 years, sac regression was observed similarly across weight classes at 49.6%, 50.6%, and 51.8% for NW, OW, and obese, respectively (P = 0.501). There was a significant difference in mean AAA diameter pre- and post-EVAR [F(2,318) = 24.37, P < 0.001] across weight classes. NW [mean reduction 4.8 mm (2.0-7.6 mm, P < 0.001)], OW [mean reduction 3.9 mm (1.5-6.3 mm, P < 0.001)], and obese [mean reduction 5.7 mm (2.3-9.1 mm, P < 0.001)] achieved similar reductions.

CONCLUSIONS

Obesity was not associated with increased mortality or reintervention in patients undergoing EVAR. Obese patients achieved similar rates of sac regression on imaging follow-up.

New Measures, Old Conclusions: Obesity Does Not Worsen Outcomes after Elective Abdominal Aortic Aneurysm Repair

Background  The “obesity paradox,” whereby the body mass index (BMI) mortality curve is “U-shaped,” is a well-studied phenomenon in vascular surgery. However, there has been an overreliance on BMI as the measure of obesity, which has shown to poorly correlate with clinical outcomes. Robust measures such as waist-hip ratio (WHR) have been suggested as a more accurate marker reflecting central obesity.

Objectives  The objectives of this study were to evaluate the correlation between BMI and WHR on postoperative morbidity and mortality after elective abdominal aortic aneurysm (AAA) repair.

Methods  Data were collected from the Leeds Vascular Institute between January 2006 and December 2016. The primary outcome was mortality and secondary outcomes included length of stay (LOS) and all-cause readmission. Binary logistic regression, linear regression, and correlation analysis were used to identify associations between BMI and WHR in relation to outcome measures.

Results  After exclusions, 432 elective AAA repairs (281 open surgical repair [OSR] and 151 endovascular aneurysm repairs [EVARs]) were identified to be eligible for the study. The combined 30-day and 4-year mortality was 1.2 and 20.1%, respectively. The 30-day readmission rate was 3.9% and the average LOS was 7.33 (standard deviation 18.5) days. BMI data was recorded for 275 patients (63.7%) and WHR for 355 patients (82.2%). Logistic regression analysis highlighted no association between BMI and WHR with mortality, readmission, or LOS following OSR or EVAR.

Conclusion  The results of this study suggest patients should not be denied treatment for AAA based on obesity alone.

Endovascular Aortic Repair in Patients of Advanced Age

PURPOSE

Treatment decisions for the elderly with abdominal aortic aneurysms (AAAs) are challenging. With advancing age, the risk of endovascular aneurysm repair (EVAR) increases while life expectancy decreases, which may nullify the benefit of EVAR. The purpose of this study was to quantify the impact of EVAR on 1-year mortality in patients of advanced age.

MATERIALS AND METHODS

The 2003-2020 Vascular Quality Initiative Database was utilized to identify patients who underwent EVAR for AAAs. Patients were included if they were 80 years of age or older. Exclusions included non-elective surgery or missing aortic diameter data. Predicted 1-year mortality of untreated AAAs was calculated based on a validated comorbidity score that predicts 1-year mortality (Gagne Index, excluding the component associated with AAAs) plus the 1-year aneurysm-related mortality without repair. The primary outcome for the study was 1-year mortality.

RESULTS

A total of 11 829 patients met study criteria. The median age was 84 years [81, 86] with 9014 (76.2%) being male. Maximal AAA diameters were apportioned as follows: 39.6% were <5.5 cm, 28.6% were 5.5-5.9 cm, 21.3% were 6.0-6.9 cm, and 10.6% were ≥7.0 cm. The predicted 1-year mortality rate without EVAR was 11.9%, which was significantly higher than the actual 1-year mortality rate with EVAR (8.2%; p<0.001). The overall rate of perioperative MACE was 4.4% (n = 516). Patients with an aneurysm diameter <5.5cm had worse actual 1-year mortality rates with EVAR compared to predicted 1-year mortality rates without EVAR. In contrast, those with larger aneurysms (≥5.5cm) had better actual 1-year mortality rates with EVAR. The benefit from EVAR for those with Gagne Indices 2-5 was largely restricted to those with AAAs ≥ 7.0cm; whereas those with Gagne Indices 0-1 experience a survival benefit for AAAs larger than 5.5 cm.

CONCLUSION

The current data suggest that EVAR decreases 1-year mortality rates for patients of advanced age compared to non-operative management in the elderly. However, the survival benefit is largely limited to those with Gagne Indices 0-1 with AAAs ≥ 5.5 cm and Gagne Indices 2-5 with AAAs ≥ 7.0 cm. Those of advanced age may benefit from EVAR, but realizing this benefit requires careful patient selection.

Association of body mass index with outcomes after thoracic endovascular aortic repair in the vascular quality initiative

OBJECTIVE

Although several studies have evaluated the impact of obesity on outcomes after abdominal aortic aneurysm repair, literature examining this association in thoracic endovascular aortic repair (TEVAR) is sparse. Here, we use a multi-institutional, international database to assess the role of body mass index (BMI) on adverse outcomes in patients who underwent TEVAR for descending thoracic aortic aneurysms (DTAA) and type B dissections (TBD).

METHODS

A retrospective review of all patients who underwent TEVAR for DTAA or TBD from August 2014 to August 2020 was performed. Patients who were underweight (BMI <18.5 kg/m²) or obese (BMI ≥30 kg/m²) were compared with those of normal weight (≥18.5 to <30 kg/m²). Adjustment for confounding was done with multivariable logistic regression or Cox proportional hazards regression as appropriate for studying postoperative or 1-year outcomes. Primary outcomes were 30-day and 1-year mortality. Other outcomes included any postoperative complication, stroke, and spinal cord ischemia.

RESULTS

A total of 3423 participants were included in the study, of whom 3.3% (n = 113) were underweight, 65.9% (n = 2253) had normal weight, and 30.8% (n = 1053) were obese. Compared with normal weight, there was no significant difference in 30-day mortality in underweight patients (odds ratio [OR], 1.81; 95% confidence interval [CI], 0.80-4.14; P = .156). Obese patients who underwent TEVAR for TBD had a 2.7-fold increase in the odds of 30-day mortality compared with normal weight (OR, 2.67; 95% CI, 1.52-4.68; P = .001). Obese and normal weight patients with DTAA had equivalent odds of 30-day mortality (OR, 1.32; 95% CI, 0.79-2.23; P = .292). The adjusted hazard of 1-year mortality was 2-fold higher in underweight patients compared with normal weight (hazard ratio, 2.15; 95% CI, 1.41-3.29; P < .001), driven by a higher risk of mortality among patients with thoracic aortic aneurysm (OR, 2.62; 95% CI, 1.63-4.21; P < .001). There was no significant difference in 1-year mortality risk between normal weight and obesity in both DTAA (OR, 0.77; 95% CI, 0.54-1.09; P = .146) and TBD (OR, 1.26; 95% CI, 0.85-1.86; P = .248).

CONCLUSIONS

In this study, obese patients who underwent TEVAR for DTAA had comparable 30-day and 1-year mortality risk as normal weight individuals. Obese patients who underwent TEVAR for TBD demonstrated a 2.7-fold increase in the odds of 30-day mortality, but equivalent mortality risk as normal weight patients at 1 year. TEVAR represents a safe minimally invasive option for treatment of DTAA in obese patients. Future work should be directed toward minimizing perioperative mortality among patients with TBD to optimize TEVAR outcomes.

The long-term implications of access complications during endovascular aneurysm repair

BACKGROUND

Access issues are one of the most common complications of endovascular aneurysm repair (EVAR). However, contemporary rates as well as risk factors for complications and the subsequent impact of access complications on mortality are poorly described.

METHODS

We studied all EVAR for intact abdominal aortic aneurysms without prior aortic surgery in the Vascular Quality Initiative between 2011 and 2018. We studied factors associated with access complications (thrombosis, embolus, wound infection, hematoma, and conversion to cutdown), as well as the interaction with female sex and the impact on survival using multilevel logistic regression and propensity weighting. Multiple imputation was used for missing data.

RESULTS

There were 33,951 EVAR during the study period (91% elective, 9% symptomatic); most cases (70%) involved an attempt at percutaneous access on at least one side, with 30% bilateral cutdowns and 0.1% iliac conduits. There were 1553 patients (4.6%) who experienced at least one access complication. Access complications were almost twice as common in female patients (7.5% vs 3.9%; P < .001). The factors associated with access complications included female sex (odds ratio [OR], 2.7; 95% confidence interval [CI], 2.0-3.6; P < .001), age (OR, 1.05 per 5 years; 95% CI, 1.02-1.1; P < .01), aortouni-iliac device (OR, 1.6; 95% CI, 1.1-2.3; P < .01), smoking (OR, 1.4; 95% CI, 1.1-1.7; P < .01), body mass index of less than 16 (OR, 1.8; 95% CI, 1.3-2.5; P = .001), dual antiplatelet therapy (1.3; 95% CI, 1.02-1.6 P = .03), prior infrainguinal bypass (OR, 1.8; 95% CI, 1.3-2.7; P < .01), and beta blocker use (OR, 1.2; 95% CI, 1.03-1.4; P = .02). Conversion from percutaneous access to open cutdown was associated with higher rates of complications than planned open cutdown (8.6% vs 2.9%; P < .001). In propensity-weighted analysis, percutaneous access was associated with significantly lower odds of access complications in women (OR, 0.6; 95% CI, 0.4-0.96; P = .03). Patients who experienced an access complication had more than four times the odds of perioperative death (OR, 4.2; 95% CI, 2.5-7.1; P < .001), and a 60% higher risk of long-term mortality (hazard ratio, 1.6; 95% CI, 1.2-2.1; P = .001). In addition to death, patients with access site complications had higher rates of other major complications, including reoperation during the index hospitalization (19% vs 1.2%; P < .001), myocardial infarction (3.5% vs 0.7%; P < .001), stroke (0.8% vs 0.2%; P < .001), acute kidney injury (12% vs 3%; P < .001), and reintubation (5.7% vs 0.8%).

CONCLUSIONS

Although access complications are infrequent in the current era, they are associated with both perioperative and long-term morbidity and mortality. Female patients in particular are at high risk of access complications, but may benefit from percutaneous access.

Obesity and postoperative outcomes of the patients with laparoscopic adrenalectomy: a systematic review and meta-analysis

Background

Studies have suggested differences in postoperative outcomes between patients with obesity and those without following adrenalectomy, but these remained to be ascertained with synthesis of available evidence. The aim of this systematic review and meta-analysis was to investigate the association between obesity and outcomes of patients after laparoscopic adrenalectomy.

Methods

We searched EMBASE, PubMed, Global Index Medicus, and Web of Science, without language restriction, to identify cohort studies published between January 1, 2000 and November 6, 2019. We considered studies with data comparing outcomes of adults with and without obesity after laparoscopic adrenalectomy. Random-effects meta-analysis was used to pool study-specific estimates. This review was registered with PROSPERO, CRD42018117070.

Results

Five studies with data on a pooled sample of 353 patients with obesity and 828 without were included in the meta-analysis. The risk of bias was moderate to low. We found no association between obesity and the various stages of postoperative complications: Clavien-Dindo grade 1 (OR = 1.57; 95%CI = 0.55–4.48; I² = 44.6%), grade 2 (OR = 1.12; 95%CI = 0.54–2.32; I² = 0.0%), grade 3 (OR = 1.79; 95%CI = 0.58–5.47; I² = 0.0%;), grade 4 (OR = 0.43; 95%CI = 0.05–3.71; I² = 0.0%), and grade 5 (death) (OR = 0.43; 95% CI = 0.02–14.31). Furthermore, no association was found between obesity and readmission rates (OR = 0.7; 95% CI = 0.13–3.62) and conversion of laparoscopic to open surgery (OR = 0.62; 95% CI = 0.16–2.34; I² = 19.5%).

Conclusions

This study suggests that obesity is not associated with complications following laparoscopic adrenalectomy. This meta-analysis might have been underpowered to detect a true association between obesity and patient outcome after laparoscopic adrenalectomy due to the small number of included studies. Larger studies are needed to clarify the role of obesity in patients undergoing laparoscopic adrenalectomy.

Open Abdominal Aortic Aneurysm Repair Is Associated with Higher Mortality Among Nonobese Patients and Higher Risk of Deep Wound Infections Among Obese Patients

BACKGROUND

Prevalence of obesity in the United States is increasing. The impact of obesity on outcomes after endovascular and open abdominal aortic aneurysm (AAA) repair is largely unknown. The purpose of this analysis was to compare the postoperative outcomes between obese and nonobese patients after these operations.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from years 2013-2015 was analyzed. Preoperative, intraoperative, and postoperative variables were compared between obese and nonobese patient groups. Then obese and nonobese patients were divided into 2 groups each, based on the type of surgery (endovascular repair of abdominal aortic aneurysms (EVAR) versus. open AAA repair), and the outcomes were compared. Then multivariant analysis was used to compare impact of operative modality on outcomes for obese and nonobese patients.

RESULTS

A total of 6,859 patients (men 80%, women 20%) underwent surgical procedures for AAA during this time period. Among these patients, 2,218 (32.3%) had body mass index (BMI) ≥30, and 4,641 (67.7%) had BMI <30. Obese patients were less likely to be > 80 years old, women, nonwhites, and smokers. Obese patients had lower mortality and higher risk of deep wound infections after surgery (P < 0.05). Among the obese patients, 83.1% underwent EVAR and 16.9% underwent open AAA repair; patients undergoing EVAR had shorter operative times, shorter length of hospital stays, and mortality (P < 0.05). Among nonobese patients, 81% underwent EVAR and 19% underwent open AAA repair. Patients undergoing EVAR had shorter duration of operation, length of hospital stay, and mortality (P < 0.05). Overall, mortality was the highest among nonobese patients undergoing open AAA repair (odds ratio (OR) 0.66, confidence interval (CI) 0.44-0.99, P < 0.05). Incidence of deep wound infections was the highest among obese patients undergoing open AAA repair (OR 4.3, CI: 1.2-14.6, P < 0.05).

CONCLUSIONS

Nonobese patients have high mortality after open AAA repair, and obese patients have higher incidence of deep wound infections after open AAA repair. For patients deemed appropriate anatomic candidates, EVAR should be preferred for nonobese patients to improve mortality and for obese patients to reduce the incidence of deep wound infections.

The Obesity-associated Risk in Open and Endovascular Repair of Abdominal Aortic Aneurysm

:

The rising pandemic of obesity in modern society should direct attention to a more comprehensive approach to abdominal aortic aneurysm (AAA) treatment in the affected population. Although overweight patients are considered prone to increased surgical risk, studies on the subject did not confirm or specify the risks well enough.

:

Associated comorbidities inevitably lead to a selection bias leaning towards endovascular abdominal aortic repair (EVAR), as a less invasive treatment option, which makes it hard to single out obesity as an independent risk factor. The increased technical difficulty often results in prolonged procedure times and increased blood loss. Several smaller studies and two analyses of national registries, including 7935 patients, highlighted the advantages of EVAR over open repair (OR) of abdominal aortic aneurysm, especially in morbidly obese population (relative risk reduction up to 47%). On the other hand, two other studies with 1374 patients combined, concluded that EVAR might not have an advantage over OR in obese patients (P = 0.52). Obesity is an established risk factor for wound infection after both EVAR and OR, which is associated with longer length of stay, subsequent major operations, and a higher rate of graft failure. Percutaneous EVAR technique could present a promising solution to reducing this complication.

:

EVAR seems like a more feasible treatment option than OR for obese patients with AAA, due to lower overall morbidity and mortality rates, as well as reduced wound-related complication rates. However, there is a clear lack of high-quality evidence on the subject, thus future prospective trials are needed to confirm this advantage.

Outcomes after elective abdominal aortic aneurysm repair in obese versus nonobese patients

OBJECTIVE

Obesity is a worldwide epidemic, particularly in Western society. It predisposes surgical patients to an increased risk of adverse outcomes. The aim of our study was to use a nationally representative vascular database and to compare in-hospital outcomes in obese vs nonobese patients undergoing elective open aortic repair (OAR) and endovascular aneurysm repair (EVAR).

METHODS

All patients undergoing elective abdominal aortic aneurysm repair were identified in the Vascular Quality Initiative database (2003-2017). Obesity was defined as body mass index ≥30 kg/m². Univariable (Student t-test and χ² test) and multivariable (logistic regression) analyses were implemented to compare in-hospital mortality and any major complications (wound infection, renal failure, and cardiopulmonary failure) in obese vs nonobese patients.

RESULTS

We identified a total of 33,082 patients undergoing elective OAR (nonobese, n = 4605 [72.4%]; obese, n = 1754 [27.6%]) and EVAR (nonobese, n = 18,338 [68.6%]; obese, n = 8385 [31.4%]). Obese patients undergoing OAR and EVAR were relatively younger compared with nonobese patients (mean age [standard deviation], 67.55 [8.26] years vs 70.27 [8.30] years and 71.06 [8.22] years vs 74.55 [8.55] years), respectively; (both P < .001). Regardless of approach, obese patients had slightly longer operative time (OAR, 259.02 [109.97] minutes vs 239.37 [99.78] minutes; EVAR, 138.27 [70.64] minutes vs 134.34 [69.98] minutes) and higher blood loss (OAR, 2030 [1823] mL vs 1619 [1642] mL; EVAR, 228 [354] mL vs 207 [312] mL; both P < .001). There was no significant difference in mortality between the two groups undergoing OAR and EVAR (OAR, 2.9% vs 3.2% [P = .50]; EVAR, 0.5% vs 0.6% [P = .76]). On multivariable analysis, obese patients undergoing OAR had 33% higher odds of renal failure (adjusted odds ratio [OR], 1.33; 95% confidence interval [CI], 1.09-1.63; P = .006) and 75% higher odds of wound infections (adjusted OR, 1.75; 95% CI, 1.11-2.76; P = .02) compared with nonobese patients. However, in patients undergoing EVAR, no association was seen between obesity and any major complications. A significant interaction was found between obesity and surgical approach in the event of renal failure, in which obese patients undergoing OAR had significantly higher odds of renal failure compared with those in the EVAR group (OR_interaction, 1.36; 95% CI, 1.05-1.75; P = .02).

CONCLUSIONS

Using a large nationally representative database, we demonstrated an increased risk of renal failure and wound infections in obese patients undergoing OAR compared with nonobese patients. On the other hand, obesity did not seem to increase the odds of major adverse outcomes in patients undergoing EVAR. Further long-term prospective studies are needed to verify the effects of obesity after abdominal aortic aneurysm repair and the implications of these findings in clinical decision-making.

Identification of Factors Influencing Cumulative Long-Term Radiation Exposure in Patients Undergoing EVAR

Patients who undergo endovascular repair of aortic aneurysms (EVAR) require life-long surveillance because complications including, in particular, endoleaks, aneurysm rupture, and graft dislocation are diagnosed in a certain share of the patient population and may occur at any time after the original procedure. Radiation exposure in patients undergoing EVAR and post-EVAR surveillance has been investigated by previous authors. Arriving at realistic exposure data is essential because radiation doses resulting from CT were shown to be not irrelevant. Efforts directed at identification of factors impacting the level of radiation exposure in both the course of the EVAR procedure and post-EVAR endovascular interventions and CTAs are warranted as potentially modifiable factors may offer opportunities to reduce the radiation. In the light of the risks found to be associated with radiation exposure and considering the findings above, those involved in EVAR and post-EVAR surveillance should aim at optimal dose management.