Sex-related Outcome Inequalities in Endovascular Aneurysm Repair

Sex-Related Differences in Proximal Neck Anatomy and Their Consequences in Patients after EVAR: A Matched Cohort Analysis

INTRODUCTION

Studies comparing male and female patients with abdominal aortic aneurysms have shown that female patients are generally older and more often experience postoperative complications after endovascular and open repair. There are also indications that female patients have more extensive neck pathologies and that they more often have postoperative complications related to proximal neck pathology.

MATERIAL AND METHODS

This retrospective study describes all consecutive female patients who underwent EVAR between 1 January 2012 and 31 December 2021. Propensity-score matching was used to obtain a matched control male cohort. Propensity scores were generated with the following anatomic parameters: infrarenal and suprarenal angulation, proximal and distal neck diameter and neck length. 1 Female patient was matched with 3 male patients.

RESULTS

A total of 160 patients were included, namely 120 male patients and 40 female patients. Due to matching, there were no significant differences regarding infrarenal and suprarenal angulation and proximal and distal neck diameter and length. All-cause and aneurysm-related mortality were comparable (p = 0.19 and p = 0.98). The necessity of neck-related secondary procedures was significantly higher in female patients (p = 0.02). In the multivariate analysis, the female sex was a significant predictor of endoleak type IA within 30 days. However, there was no significant association between intraoperative endoleak type IA and endoleak type IA at the end of follow-up.

CONCLUSIONS

This study suggests that there was a higher initial incidence of endoleak type IA in female patients, despite thematched preoperative anatomic parameter. Due to the relatively low number of included female patients, conclusions should be drawn carefully.

Sex Influence on Fenestrated and Branched Endovascular Aortic Aneurysm Repair: Outcomes From a National Multicenter Registry

Introduction:

Women are generally underrepresented in trials focusing on aortic aneurysm. Nevertheless, sex-related differences have recently emerged from several studies and registries. The aim of this research was to assess whether sex-related anatomical disparities existed in fenestrated and branched aortic repair candidates and whether these discrepancies could influence endovascular repair outcomes.

Methods:

Data from all consecutive patients treated during the 2008–2019 period within the Italian Multicenter fenestrated or branched endovascular aortic repair (F/BEVAR) Registry were included in the present study. Propensity matching was performed using a logistic regression model adjusted for demographic data and comorbidities to obtain comparable male and female samples. The selection model led to a final study population of 176 patients (88 women and 88 men) among the total initial cohort of 596. Study endpoints were technical and clinical success, overall survival, aneurysm-related death, and reintervention rates evaluated at 30 days and during follow-up.

Results:

Twenty-eight patients (15.9%) received urgent/emergent repair. In most of the cases (71.6%), women received treatment for extensive thoracoabdominal pathology (Crawford type I, II, or III aneurysm rather than type IV or juxta-pararenal) versus 46.6% of men (p=0.001). Female patients presented with more challenging iliac accesses with at least one side considered hostile in 27.3% of the cases (vs 13.6% in male patients, p=0.039). Finally, women had significantly smaller visceral vessels. Women had significantly worse operative outcomes, with an 86.2% technical success rate versus 96.6% in the male population (p=0.016). No differences were recorded in terms of 30-day reinterventions between men and women. The 5-year estimate of freedom from late reintervention, according to Kaplan-Meier analysis, was 85.6% in men versus 81.6% in women (p=ns). No aneurysm-related death was recorded during follow-up (median observational time, 23 months [interquartile range, 7–45 months]).

Conclusion:

Women presented a significantly higher incidence of thoracoabdominal aneurysms, smaller visceral vessels, and more complex iliofemoral accesses, resulting in a significantly lower technical success after F/BEVAR. Further studies assessing sex-related differences are needed to properly determine the impact on outcomes and stratify procedural risks.

Clinical Impact

Women are generally underrepresented in trials focusing on aortic aneurysms. Aiming to assess whether sex may affect outcomes after a complex endovascular aortic repair, a propensity score selection was applied to a total population of 596 patients receiving F/BEVAR aortic repair with the Cook platform, matching each treated female patient with a corresponding male patient. Women presented more frequently a thoracoabdominal aneurysm extent, smaller visceral vessels, and complex iliofemoral accesses, resulting in significantly worse operative outcomes, with an 86.2% technical success versus 96.6% (p=0.016). No differences were recorded in terms of short-term and mid-term reinterventions. According to these results, careful and critical assessment should be posed in case of female patients receiving complex aortic repair, especially regarding preoperative anatomical evaluation and clinical selection with appropriate surgical risk stratification.

One-Year Results of the INSIGHT Study on Endovascular Treatment of Abdominal Aortic Aneurysms

OBJECTIVE

Endovascular repair of abdominal aortic aneurysms (AAA) using the INCRAFT™ AAA Stent Graft System was safe and effective in regulatory approval studies. We herein report on the 1-year results of a real-world clinical study.

METHODS

The INSIGHT study is a multi-center, prospective, open label, post-approval study conducted to continually evaluate the safety and performance of the INCRAFT ™ System. Between 2015 and 2016, 150 consecutive patients with AAA at 23 centers in Europe were treated with the device in routine clinical practice. The primary endpoint was freedom from major adverse events (MAEs), namely death, myocardial infarction (MI), cerebrovascular accident (CVA) and renal failure, within 30 days of the index procedure. Endpoint data were assessed by a core laboratory. The secondary endpoints included technical success at the conclusion of the procedure and clinical success.

RESULTS

All 150 patients studied (mean age: 73.6 ± 8.0 and 89.3% men) met the primary endpoint without MAEs at 30-day follow up. Technical success was achieved in 99.3% of patients without stent fractures at 30 days. Among the 146 patients eligible for 1-year follow-up, the MAE rate was 8.2%, i.e., 12 patients suffered 13 MAEs: CVA in 8, MI in 1, and 4 died (resulting in a 2.7% all-cause mortality rate). There were no reports of new onset renal failure requiring dialysis. Only 2.7% of patients had type I endoleak and no III endoleaks were identified through 1 year. The rate of clinical success at 1 year was 91.8%.

CONCLUSIONS

The 1-year results of this multicenter real-world study underscore the safety and effectiveness of endovascular treatment of AAA with the INCRAFT System in routine clinical practice.

Editor's Choice - Systematic Review and Meta-Analysis of Sex Specific Differences in Adverse Events After Open and Endovascular Intact Abdominal Aortic Aneurysm Repair: Consistently Worse Outcomes for Women

OBJECTIVE

Previously, reports have shown that women experience a higher mortality rate than men after elective open (OAR) and endovascular (EVAR) repair of abdominal aortic aneurysm (AAA). With recent improvements in overall AAA repair outcomes, this study aimed to identify whether sex specific disparity has been ameliorated by modern practice, and to define sex specific differences in peri- and post-operative complications and pre-operative status; factors which may contribute to poor outcome.

METHODS

This was a systematic review, meta-analysis, and meta-regression of sex specific differences in 30 day mortality and complications conducted according to PRISMA guidance (Prospero registration CRD42020176398). Papers with ≥ 50 women, reporting sex specific outcomes, following intact primary AAA repair, from 2000 to 2020 worldwide were included; with separate analyses for EVAR and OAR. Data sources were Medline, Embase, and CENTRAL databases 2005 - 2020 searched using ProQuest Dialog.

RESULTS

Twenty-six studies (371 215 men, 65 465 women) were included. Meta-analysis and meta-regression indicated that sex specific odds ratios (ORs) for 30 day mortality were unchanged from 2000 to 2020. Mortality risk was higher in women for OAR and more so for EVAR (OR [95% CI] 1.49 [1.37 - 1.61]; 1.86 [1.59 - 2.17], respectively) and this remained following multivariable risk adjustment. Transfusion, pulmonary complications, and bowel ischaemia were more common in women after OAR and EVAR (OAR: ORs 1.81 [1.60 - 2.04], 1.40 [1.28 - 1.53], 1.54 [1.36 - 1.75]; EVAR: ORs 2.18 [2.08 - 2.29] 1.44 [1.17 - 1.77], 1.99 [1.51 - 2.62], respectively). Arterial injury, limb ischaemia, renal and cardiac complications were more common in women after EVAR (ORs 3.02 [1.62 - 5.65], 2.13 [1.48 - 3.06], 1.46 [1.22 - 1.72] and 1.19 [1.03 - 1.37], respectively); the latter was associated with greater mortality risk on meta-regression.

CONCLUSION

Increased mortality risk for women following AAA repair remains. Women had a higher incidence of transfusion, pulmonary and bowel complications after EVAR and OAR. Higher mortality risk ratios for EVAR may result from cardiac complications, additional arterial injury, and embolisation, leading to renal and limb ischaemia. These findings indicate possible causes for observed outcome disparities and targets for quality improvement.

Differences in Comorbidities Between Women and Men Treated with Elective Repair for Abdominal Aortic Aneurysms: A Systematic Review and Meta-Analysis

OBJECTIVES

Elective abdominal aortic aneurysm (AAA) repair is performed to prevent rupture. For reasons as yet unknown, the 30-day mortality risk after elective AAA repair is higher in women than in men. We hypothesised that this higher risk might be related to differences in comorbidity.

METHODS

Systematic review (PROSPERO CRD42019133314) according to PRISMA guidelines. A search in the EMBASE/MEDLINE/CENTRAL databases identified 1870 studies that included patients who underwent elective AAA repair (final search February 17^th, 2021). Ultimately, 28 studies were included and all reported comorbidities were categorised into 17 comorbidity groups. Additionally, 15 groups of clearly defined comorbidities were used for sensitivity analysis. For both groups, meta-analyses of each comorbidity were performed to estimate the difference in pooled prevalence between women and men with a random effects model.

RESULTS

When analysing data of all reported comorbidities (17 groups), smoking [risk difference (RD) 11%, 95% confidence interval (CI) 4-18], diabetes (RD 3%, 95% CI 2-4), ischaemic heart disease (RD 12%, 95% CI 8-16), arrhythmia (RD 3%, 95% CI 0.4-5), liver disease (RD 0.1%, 95% CI 0.01-0.2), and cancer (RD 3%, 95% CI 2-4)) were less prevalent in women, whereas, hypertension (RD 4%, 95% CI 3-6) and pulmonary disease (RD 4%, 95% CI 3-5) were more prevalent in women. At the time of surgery women were significantly older than men (74.9 years versus 72.4; mean difference 2.4 years (95% CI 2.1-2.7)). In the sensitivity analysis of 15 comorbidity groups, the same comorbidities remained significantly different between women and men, except smoking and arrhythmia. Women had a higher mortality risk than men (RD 1%, 95% CI 1-2).

CONCLUSIONS

Although women undergoing elective AAA repair have fewer baseline comorbidities than men, their 30-day mortality risk is higher. In-depth studies on the cause of death in women after elective AAA repair are needed to explain this discrepancy in mortality.

Sex-related outcomes after fenestrated-branched endovascular aneurysm repair for thoracoabdominal aortic aneurysms in the U.S. Fenestrated and Branched Aortic Research Consortium

OBJECTIVE

Fenestrated-branched endovascular aneurysm repair (FBEVAR) has expanded the treatment of patients with thoracoabdominal aortic aneurysms (TAAAs). Previous studies have demonstrated that women are less likely to be treated with standard infrarenal endovascular aneurysm repair because of anatomic ineligibility and experience greater mortality after both infrarenal and thoracic aortic aneurysm repair. The purpose of the present study was to describe the sex-related outcomes after FBEVAR for treatment of TAAAs.

METHODS

The data from 886 patients with extent I to IV TAAAs (excluding pararenal or juxtarenal aneurysms), enrolled in eight prospective, physician-sponsored, investigational device exemption studies from 2013 to 2019, were analyzed. All data were collected prospectively, audited and adjudicated by clinical events committees and/or data safety monitoring boards, and subject to Food and Drug Administration oversight. All the patients had been treated with Cook-manufactured patient-specific FBEVAR devices or the Cook t-Branch off-the-shelf device (Cook Medical, Brisbane, Australia).

RESULTS

Of the 886 patients who underwent FBEVAR, 288 (33%) were women. The women had more extensive aneurysms and a greater prevalence of diabetes (33% vs 26%; P = .043) but a lower prevalence of coronary artery disease (33% vs 52%; P < .0001) and previous infrarenal endovascular aneurysm repair (7.6% vs 16%; P < .001). The women had required a longer operative time from incision to surgery end (5.0 ± 1.8 hours vs 4.6 ± 1.7 hours; P < .001), experienced lower technical success (93% vs 98%; P = .002), and were less likely to be discharged to home (72% vs 83%; P = .009). Despite the smaller access vessels, the women did not have an increased incidence of access site complications. Also, the 30-day outcomes were broadly similar between the sexes. At 1 year, no differences were found between the women and men in freedom from type I or III endoleak (91.4% vs 92.0%; P = .64), freedom from reintervention (81.7% vs 85.3%; P = .10), target vessel instability (87.5% vs 89.2%; P = .31), and survival (89.6% vs 91.7%; P = .26). The women had a greater incidence of postoperative sac expansion (12% vs 6.5%; P = .006). Multivariable modeling adjusted for age, aneurysm extent, aneurysm size, urgent procedure, and renal function showed that patient sex was not an independent predictor of survival (hazard ratio, 0.83; 95% confidence interval, 0.50-1.37; P = .46).

CONCLUSIONS

Women undergoing FBEVAR demonstrated metrics of increased complexity and had a lower level of technical success, especially those with extensive aneurysms. Compared with the men, the women had similar 30-day mortality and 1-year outcomes, with the exception of an increased incidence of sac expansion. These data have demonstrated that FBEVAR is safe and effective for women and men but that further efforts to improve outcome parity are indicated.

Women have similar mortality but higher morbidity than men after elective endovascular abdominal aortic aneurysm repair

OBJECTIVE

Sex disparities regarding outcomes for women after open and endovascular abdominal aortic aneurysm repair have been well-documented. The purpose of this study was to review whether these disparities were also present at our institution for elective endovascular aneurysm repair (EVAR) and whether specific factors predispose female patients to negative outcomes.

METHODS

All elective EVARs were identified from our three sites (Florida, Minnesota, and Arizona) from 2000 to 2018. The primary outcome was in-hospital mortality and three-year mortality. Secondary outcomes included complications requiring return to the operating room, length of hospitalization (LOH), intensive care unit (ICU) days, and location of discharge after hospitalization. Multivariable logistic regression models were used to assess for the risk of complications.

RESULTS

There were 1986 EVARs; 1754 (88.3%) were performed in male and 232 (11.7%) in female patients. Female patients were older (79 years [interquartile range (IQR), 72-83 years] vs 76 years [IQR, 70-81 years]; P < .001), had a lower body mass index (median, 26.1 kg/m² [IQR, 22.1-31.0 kg/m²] vs 28.3 kg/m² [IQR, 25.3-31.6 kg/m²]; P < .001 and hematocrit (median, 37.6% [IQR, 33.4%-40.6%] vs 39.4% [IQR, 35.6%-42.6%]; P < .001) and had higher glomerular filtration rate (median, 84.4 mL/min per 1.73m² [IQR, 62.3-103 mL/min/1.73 m²] vs 51.1 mL/min/1.73 m² [IQR, 41.8-60.8 mL/min/1.73 m²]; P < .001. Female patients were also more likely to be active smokers (15.3% vs 13.1%; P < .001) and have chronic obstructive pulmonary disease (24.7% vs 15.3%; P = .001). They were less likely to have coronary artery disease (31.6% vs 45.6%; P < .001). Aneurysms in women were slightly smaller in size (median, 54 mm [IQR, 50.0-58.0 mm] vs 55 mm [IQR, 51.0-60.0 mm]; P = .004). In-hospital mortality and mortality at the 3-year follow-up was not significant between female and male patients (0.86% vs 0.17%; P = .11 and 38.4% vs 36.2%; P = .57). However, female patients returned to the operating room with a greater frequency than male patients (3.9% vs 1.4%; P = .011). LOH (mean, 3.4 ± 3.8 days vs 2.5 ± 2.4 days; P < .001) and ICU days (mean, 0.3 ± 2.0 days vs 0.1 ± 0.5 days; P < .001) were longer for female patients. After hospitalization, female patients were discharged to rehabilitation facilities in greater proportion (12.7% vs 3.1%; P < .001) than their male counterparts. On multivariable analysis, female sex was associated with a return to the operating room (odds ratio, 6.4; 95% confidence interval [CI], 1.4-3.5; P = .02), longer LOH (Coef 4.0; 95% CI, 1.0-2.5; P = .00007), more ICU days (Coef 2.8; 95% CI, 1.1-3.0; P = .005), and a greater likelihood of posthospitalization rehabilitation facility placement (odds ratio, 5.8; 95% CI, 1.5-2.4; P = .0001).

CONCLUSIONS

Our three-site, single-institution data support sex disparities to the detriment of female patients regarding return to the operating room after EVAR, LOH, ICU days, and discharge to rehabilitation facility. However, we found no differences for in-hospital or 3-year mortality.

Primary Care Screening for Abdominal Aortic Aneurysm: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Ruptured abdominal aortic aneurysms (AAAs) have mortality estimated at 81%.

OBJECTIVE

To systematically review the evidence on benefits and harms of AAA screening and small aneurysm treatment to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed (publisher supplied only), Database of Abstracts of Reviews of Effects, and Cochrane Central Register of Controlled Trials for relevant English-language studies published through September 2018. Surveillance continued through July 2019.

STUDY SELECTION

Trials of AAA screening benefits and harms; trials and cohort studies of small (3.0-5.4 cm) AAA treatment benefits and harms.

DATA EXTRACTION AND SYNTHESIS

Two investigators independently reviewed abstracts and full-text articles and extracted data. The Peto method was used to pool odds ratios (ORs) for AAA-related mortality, rupture, and operations; the DerSimonian and Laird random-effects model was used to pool calculated risk ratios for all-cause mortality.

MAIN OUTCOMES AND MEASURES

AAA and all-cause mortality; AAA rupture; treatment complications.

RESULTS

Fifty studies (N = 323 279) met inclusion criteria. Meta-analysis of population-based randomized clinical trials (RCTs) estimated that a screening invitation to men 65 years or older was associated with a reduction in AAA-related mortality over 12 to 15 years (OR, 0.65 [95% CI, 0.57-0.74]; 4 RCTs [n = 124 926]), AAA-related ruptures over 12 to 15 years (OR, 0.62 [95% CI, 0.55-0.70]; 4 RCTs [n = 124 929]), and emergency surgical procedures over 4 to 15 years (OR, 0.57 [95% CI, 0.48-0.68]; 5 RCTS [n = 175 085]). In contrast, no significant association with all-cause mortality benefit was seen at 12- to 15-year follow-up (relative risk, 0.99 [95% CI 0.98-1.00]; 4 RCTs [n = 124 929]). One-time screening was associated with significantly more procedures over 4 to 15 years in the invited group compared with the control group (OR, 1.44 [95% CI, 1.34-1.55]; 5 RCTs [n = 175 085]). Four trials (n = 3314) of small aneurysm surgical treatment demonstrated no significant difference in AAA-related mortality or all-cause mortality compared with surveillance over 1.7 to 12 years. These 4 early surgery trials showed a substantial increase in procedures in the early surgery group. For small aneurysm treatment, registry data (3 studies [n = 14 424]) showed that women had higher surgical complications and postoperative mortality compared with men.

CONCLUSIONS AND RELEVANCE

One-time AAA screening in men 65 years or older was associated with decreased AAA-related mortality and rupture rates but was not associated with all-cause mortality benefit. Higher rates of elective surgery but no long-term differences in quality of life resulted from screening.

Editor's Choice - Sex Related Differences in Peri-operative Mortality after Elective Repair of an Asymptomatic Abdominal Aortic Aneurysm in the Netherlands: a Retrospective Analysis of 2013 to 2018

OBJECTIVE

The aim was to compare peri-operative (30 day and/or in hospital) mortality between women and men in the Netherlands after elective repair of an asymptomatic abdominal aortic aneurysm (AAA).

METHODS

This was a retrospective study using data from the Dutch Surgical Aneurysm Audit (DSAA), a mandatory nationwide registry of patients undergoing AAA repair in the Netherlands. Patients who underwent elective open surgical (OSR) or endovascular aneurysm repair (EVAR) of an asymptomatic abdominal aortic aneurysm (AAA) between 2013 and 2018 were included. Absolute risk differences (ARDs) with 95% confidence intervals (CIs) in peri-operative mortality between women and men were estimated. Logistic regression analyses were performed to estimate adjusted odds ratios (ORs) for mortality. Confounders included pre-operative cardiac and pulmonary comorbidity, serum haemoglobin, serum creatinine, type of AAA repair, and AAA diameter.

RESULTS

Some 1662 women and 9637 men were included, of whom 507 (30.5%) women and 2056 (21.3%) men underwent OSR (p < .001). Crude peri-operative mortality was 3.01% in women and 1.60% in men (ARD = 1.41%, 95% CI 0.64-2.37). This significant difference was also observed for OSR (ARD = 2.63%, 95% CI 0.43-5.36), but not for EVAR (ARD = 0.36%, 95% CI -0.16 to 1.17). Female sex remained associated with peri-operative mortality after adjusting for confounders (OR = 1.79, 95% CI 1.20-2.65, p = .004), which was similarly observed for OSR (OR = 1.85, 95% CI 1.16-2.94, p = .01), but not for EVAR (OR = 1.46, 95% CI 0.72-2.95, p = .29).

CONCLUSIONS

Peri-operative mortality after elective repair of an asymptomatic AAA in the Netherlands is higher in women than in men. This disparity might be explained by the higher peri-operative mortality in women undergoing OSR, because no such difference was found in patients undergoing EVAR. Yet, it is likely that there are unaccounted factors at play since female sex remained significantly associated with mortality after adjusting for type of repair.

Screening women aged 65 years or over for abdominal aortic aneurysm: a modelling study and health economic evaluation

BACKGROUND

Abdominal aortic aneurysm (AAA) screening programmes have been established for men in the UK to reduce deaths from AAA rupture. Whether or not screening should be extended to women is uncertain.

OBJECTIVE

To evaluate the cost-effectiveness of population screening for AAAs in women and compare a range of screening options.

DESIGN

A discrete event simulation (DES) model was developed to provide a clinically realistic model of screening, surveillance, and elective and emergency AAA repair operations. Input parameters specifically for women were employed. The model was run for 10 million women, with parameter uncertainty addressed by probabilistic and deterministic sensitivity analyses.

SETTING

Population screening in the UK.

PARTICIPANTS

Women aged ≥ 65 years, followed up to the age of 95 years.

INTERVENTIONS

Invitation to ultrasound screening, followed by surveillance for small AAAs and elective surgical repair for large AAAs.

MAIN OUTCOME MEASURES

Number of operations undertaken, AAA-related mortality, quality-adjusted life-years (QALYs), NHS costs and cost-effectiveness with annual discounting.

DATA SOURCES

AAA surveillance data, National Vascular Registry, Hospital Episode Statistics, trials of elective and emergency AAA surgery, and the NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP).

REVIEW METHODS

Systematic reviews of AAA prevalence and, for elective operations, suitability for endovascular aneurysm repair, non-intervention rates, operative mortality and literature reviews for other parameters.

RESULTS

The prevalence of AAAs (aortic diameter of ≥ 3.0 cm) was estimated as 0.43% in women aged 65 years and 1.15% at age 75 years. The corresponding attendance rates following invitation to screening were estimated as 73% and 62%, respectively. The base-case model adopted the same age at screening (65 years), definition of an AAA (diameter of ≥ 3.0 cm), surveillance intervals (1 year for AAAs with diameter of 3.0-4.4 cm, 3 months for AAAs with diameter of 4.5-5.4 cm) and AAA diameter for consideration of surgery (5.5 cm) as in NAAASP for men. Per woman invited to screening, the estimated gain in QALYs was 0.00110, and the incremental cost was £33.99. This gave an incremental cost-effectiveness ratio (ICER) of £31,000 per QALY gained. The corresponding incremental net monetary benefit at a threshold of £20,000 per QALY gained was -£12.03 (95% uncertainty interval -£27.88 to £22.12). Almost no sensitivity analyses brought the ICER below £20,000 per QALY gained; an exception was doubling the AAA prevalence to 0.86%, which resulted in an ICER of £13,000. Alternative screening options (increasing the screening age to 70 years, lowering the threshold for considering surgery to diameters of 5.0 cm or 4.5 cm, lowering the diameter defining an AAA in women to 2.5 cm and lengthening the surveillance intervals for the smallest AAAs) did not bring the ICER below £20,000 per QALY gained when considered either singly or in combination.

LIMITATIONS

The model for women was not directly validated against empirical data. Some parameters were poorly estimated, potentially lacking relevance or unavailable for women.

CONCLUSION

The accepted criteria for a population-based AAA screening programme in women are not currently met.

FUTURE WORK

A large-scale study is needed of the exact aortic size distribution for women screened at relevant ages. The DES model can be adapted to evaluate screening options in men.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015020444 and CRD42016043227.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Should Abdominal Aortic Aneurysms in Women be Repaired at a Lower Diameter Threshold?

Abdominal aortic aneurysm (AAA) primarily affects male patients; however, female patients with AAA have a faster rate of aneurysm growth, have higher risk of rupture even at smaller diameters, and have worse outcomes following repair of ruptured and intact aneurysms. Furthermore, early natural history studies and randomized controlled trials evaluating surveillance versus repair in small aneurysms were conducted primarily in male patients. Therefore, there are limited data regarding the ideal threshold for elective repair of AAA in women, either by aortic diameter or by alternative measures. We review the existing literature regarding AAA in women and consider the most appropriate threshold for repair.

Indications, risk factors, and outcomes of 30-day readmission after infrarenal abdominal aneurysm repair

OBJECTIVE

Reducing readmissions is an important target for improving patient care and enhancing health care quality and cost-effectiveness. The aim of this study was to assess rates, risk factors, and indications of 30-day readmission after open aortic repair (OAR) and endovascular aneurysm repair (EVAR) of infrarenal abdominal aortic aneurysms (AAAs).

METHODS

A retrospective analysis of the Premier Healthcare Database from 2009 to 2015 was performed. Indications for readmission after the index procedure, risk factors, and outcomes of the index admission and rehospitalization were evaluated. Multivariate logistic models were used to assess the association between 30-day readmission and different patient and hospital factors.

RESULTS

A total of 33,332 AAA repair procedures were identified: 27,483 (82.5%) EVAR and 5849 (17.5%) OAR. The overall rate of 30-day readmission was 8.1%, and it was greater after OAR (12.9% vs 7.1% in EVAR; P < .001). In general, the most common specific readmission diagnoses were infectious complications (16.1%), followed by respiratory and cardiac complications (11.8% and 11.3%, respectively). After multivariate adjustment, OAR was associated with higher 30-day readmission compared with EVAR (adjusted odds ratio, 1.11; 95% confidence interval, 1.0-1.2; P = .04). Other risk factors of 30-day readmission included female gender, emergency and urgent procedures, certain patient comorbidities (dyslipidemia, congestive heart failure, history of transient ischemic attack, previous cardiac surgery, chronic obstructive pulmonary disease, asthma, chronic kidney disease, peripheral vascular disease, and history of malignant disease), and hemorrhage/shock/bleeding occurring during the index admission as well as nonhome discharge. Readmitted patients had an overall in-hospital mortality of 3.6% and paid a median rehospitalization cost of $7757.

CONCLUSIONS

Our study shows that around 8.1% of patients undergoing infrarenal AAA repair were readmitted within 30 days. Because many readmissions are unrelated to the index procedure or caused by factors that are nonmodifiable or nonidentifiable at discharge, efforts should focus on discharge planning and improving the decision process regarding discharge destination as well as postdischarge coordination of care for high-risk patients.

Morphological suitability for endovascular repair, non-intervention rates, and operative mortality in women and men assessed for intact abdominal aortic aneurysm repair: systematic reviews with meta-analysis

BACKGROUND

Prognosis for women with abdominal aortic aneurysm might be worse than the prognosis for men. We aimed to systematically quantify the differences in outcomes between men and women being assessed for repair of intact abdominal aortic aneurysm using data from study periods after the year 2000.

METHODS

In these systematic reviews and meta-analysis, we identified studies (randomised, cohort, or cross-sectional) by searching MEDLINE, Embase, CENTRAL, and grey literature published between Jan 1, 2005, and Sept 2, 2016, for two systematic reviews and Jan 1, 2009, and Sept 2, 2016, for one systematic review. Studies were included if they were of both men and women, with data presented for each sex separately, with abdominal aortic aneurysms being assessed for aneurysm repair by either endovascular repair (EVAR) or open repair. We conducted three reviews based on whether studies reported the proportion morphologically suitable (within manufacturers' instructions for use) for EVAR (EVAR suitability review), non-intervention rates (non-intervention review), and 30-day mortality (operative mortality review) after intact aneurysm repair. Studies had to include at least 20 women (for the EVAR suitability review), 20 women (for the non-intervention review), and 50 women (for the operative mortality review). Studies were excluded if they were review articles, editorials, letters, or case reports. For the operative review, studies were also excluded if they only provided hazard ratios or only reported in-hospital mortality. We assessed the quality of the studies using the Newcastle-Ottawa scoring system, and contacted authors for the provision of additional data if needed. We combined results across studies by random-effects meta-analysis. This study is registered with PROSPERO, number CRD42016043227.

FINDINGS

Five studies assessed the morphological eligibility for EVAR (1507 men, 400 women). The overall pooled proportion of women eligible (34%) for EVAR was lower than it was in men (54%; odds ratio [OR] 0·44, 95% CI 0·32-0·62). Four single-centre studies reported non-intervention rates (1365 men, 247 women). The overall pooled non-intervention rates were higher in women (34%) than men (19%; OR 2·27, 95% CI 1·21-4·23). The review of 30-day mortality included nine studies (52 018 men, 11 076 women). The overall pooled estimate for EVAR was higher in women (2·3%) than in men (1·4%; OR 1·67, 95% CI 1·38-2·04). The overall estimate for open repair also was higher in women (5·4%) than in men (2·8%; OR 1·76, 95% CI 1·35-2·30).

INTERPRETATION

Compared with men, a smaller proportion of women are eligible for EVAR, a higher proportion of women are not offered intervention, and operative mortality is much higher in women for both EVAR and open repair. The management of abdominal aortic aneurysm in women needs improvement.

FUNDING

National Institute for Health Research (UK).