Association between sex and perioperative mortality following endovascular repair for ruptured abdominal aortic aneurysms

A systematic review and meta-analysis on early mortality after abdominal aortic aneurysm repair in females in urgent and elective setting

OBJECTIVE

Females represent a group of patients with higher mortality after abdominal aortic aneurysm (AAA), endovascular (EVAR) or open (OSR), repair. This systematic review aimed to evaluate the 30-day mortality after AAA repair in females, comparing both EVAR and OSR, in elective and urgent settings.

METHODS

The protocol of the review was registered to the PROSPERO (CRD42021242686). A search of the English literature was conducted, using PubMed, EMBASE and CENTRAL databases, from inception to March 5, 2021, using the Systematic Reviews and Meta-Analysis guidelines (PRISMA). Only studies reporting on 30-day mortality of AAA repair, in urgent and elective setting, comparing EVAR and OSR, in female population were eligible. Patients were stratified according to the need for elective or urgent repair. Symptomatic and ruptured cases were included into the urgent group. Individual studies were assessed for risk of bias using the ROBINS-I tool. The GRADE approach was used to evaluate the quality of evidence. The primary outcome was 30-day mortality after AAA repair in the female population, comparing EVAR and OSR. The outcomes were summarized as odds ratio along with their 95% confidence intervals (CI), through a paired meta-analysis.

RESULTS

Eight studies reported data on 30-day mortality following AAA repair. A total of 56,982 females (22,995 EVAR vs. 33,987 OSR) were included. A significantly reduced total 30-day mortality rate was recorded among females that underwent EVAR compared to OSR (OR, 0.25; 95% CI, 0.23-0.27; P<.001, Ι²=86%). Also a reduced 30-day mortality was found in females that underwent elective EVAR compared to OSR (OR, 0.37; 95% CI, 0.33-0.41; P< .001, Ι²=48%). Despite that OSR was more frequently offered in the urgent setting (OR, 0.21; 95% CI, 0.19-0.23; P< .001, Ι²=84%), EVAR was associated with a reduced 30-day mortality (OR, 0.48; 95% CI, 0.40-0.57; P<.001, Ι²=0%).

CONCLUSIONS

In females, EVAR is associated with lower 30-day mortality in both elective and urgent AAA repair, although it appears as less likely to be offered in the setting of urgent AAA repair.

Sex differences in Japanese patients with ruptured aortic aneurysms

OBJECTIVE

This study aimed to assess the sex differences in clinical presentation and outcomes of Japanese patients with ruptured aortic aneurysm (rAA) using a large nationwide claims-based database in Japan.

METHODS

We identified patients hospitalized in certified teaching hospitals in Japan with rAA between April 1, 2012, and March 31, 2015. Patients' characteristics and in-hospital outcomes were compared between men and women. The Barthel index was used for evaluating functional status at discharge by examining the ability to perform basic daily activities.

RESULTS

Of 7086 eligible patients, 32.3% (2291/7086) were women. Women were older than men (81.9 years vs 76.1 years; P < .001), had higher prevalence of coma at admission (33.2% vs 25.2%; P < .001), and were less likely to undergo emergency operation including endovascular aneurysm repair (35.7% vs 51.1%; P < .001). The unadjusted mortality rate (62.5% vs 52.0%; P < .001) and Barthel index at discharge (78.7 vs 86.1; P < .001) were significantly worse in women than in men. However, multilevel mixed-effect logistic regression analyses showed that female sex itself was not an independent predictor for in-hospital death (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.78-1.04; P = .17). Older age, coma at admission, and vasopressor use were detected as independent predictors for in-hospital death. The same results were confirmed for each rupture site. Stratified analyses showed that older women (threshold, 80 years; OR, 0.81; 95% CI, 0.66-0.98; P = .028) and those who underwent emergency operation (OR, 0.75; 95% CI, 0.61-0.93; P = .009) showed significantly better outcomes than men.

CONCLUSIONS

In a univariate analysis, female patients with rAA showed worse mortality than men because of their older age, more severe clinical presentation, and low emergency operation rate. However, after adjustment for covariates, female sex itself was not associated with increased mortality.

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.

Gender differences in abdominal aortic aneurysm therapy - a systematic review

This article analyses if and to what extent gender differences exist in abdominal aortic aneurysm (AAA) therapy. For this purpose Medline (PubMed) was searched from January 1999 to January 2018. Keywords were: "abdominal aortic aneurysm", "gender", "prevalence", "EVAR", and "open surgery of abdominal aortic aneurysm". Regardless of open or endovascular treatment of abdominal aortic aneurysms, women have a higher rate of complications and longer hospitalizations compared to men. The majority of studies showed that women have a lower survival rate for surgical and endovascular treatment of abdominal aneurysms after both elective and emergency interventions. Women receive less surgical/interventional and protective medical treatment. Women seem to have a higher risk of rupture, a lower survival rate in AAA, and a higher rate of complications, regardless of endovascular or open treatment. The gender differences may be due to a higher age of women at diagnosis and therapy associated with higher comorbidity, but also because of genetic, hormonal, anatomical, biological, and socio-cultural differences. Strategies for treatment in female patients must be further defined to optimize outcome.

Gender differences in abdominal aortic aneurysms in Germany using health insurance claims data

Abstract. Background: Endovascular aortic repair (EVAR) has emerged as standard of care for abdominal aortic aneurysm (AAA). Real-world evidence is limited to compare this technology to open repair (OAR). Major gaps exist related to short-term and long-term outcomes, particularly in respect of gender differences. Materials and methods: Health insurance claims data from Germany’s third largest insurance provider, DAK-Gesundheit, was used to investigate invasive in-hospital treatment of intact (iAAA) and ruptured AAA (rAAA). Patients operated between October 2008 and April 2015 were included in the study. Results: A total of 5,509 patients (4,966 iAAA and 543 rAAA) underwent EVAR or OAR with a median follow-up of 2.44 years. Baseline demographics, comorbidities, and clinical characteristics of DAK-G patients were assessed. In total, 84.6 % of the iAAA and 79.9 % of the rAAA were male. Concerning iAAA repair, the median age (74 vs. 73 years, p < .001) compared to men was higher in females, but their EVAR-rate (66.8 % vs. 71.1 %, p = .018) was lower. Besides higher age of female patients (80 vs. 75 years, p < .001), no further statistically significant differences were seen following rAAA repair. In-hospital mortality was slightly lower in males compared to females following iAAA (2.3 % vs. 3.1 %, p = .159) and rAAA (37.3 % vs. 43.1 %, p = .273) repair. Concerning iAAA repair, a higher rate of female patients was transferred to another hospital (3.7 % vs. 2.0 %, p = 0.008) or discharged to rehabilitation (6.0 % vs. 2.7 %, p < .001) compared to male patients. Conclusions: In this large German claims data cohort, women are generally older and more often transferred to another hospital or discharged to rehab following iAAA repair. Nonetheless, no significantly increased risk of in-hospital or late death appeared for women in multivariate analyses. Further studies are necessary to evaluate the impact of recent gender-specific treatment strategies on overall outcome under real-world settings.

Influence of Gender on Abdominal Aortic Aneurysm Repair in the Community

BACKGROUND

Women have been shown to experience inferior outcomes following intact and ruptured abdominal aortic aneurysm (AAA) treatment in endovascular aneurysm repair (EVAR) and open surgical repair (OSR) groups. The goal of our study was to compare gender-specific presentation, management, and early outcomes after AAA repair using a statewide registry.

METHODS

We utilized the Washington State's Vascular Interventional Surgical Care and Outcomes Assessment Program registry data collected in 19 hospitals from July 2010 to September 2013. Demographics, presentation, procedural data, and outcomes in elective and emergent AAA repair groups were analyzed.

RESULTS

We identified 1,231 patients (19.6% women) who underwent intact (86.4%) or ruptured AAA (13.6%) repairs. Nine thousand seventy-two (79.0%) patients had EVAR and 259 (21.0%) had OSR. Men and women were of equivalent age and had similar comorbidities, except that women had less coronary artery disease (P < 0.01) and were more likely to suffer from chronic obstructive pulmonary disease (P = 0.05). Women had smaller aneurysm diameters (5.8 ± 1.1 vs. 6.2 ± 1.8 cm, P < 0.01) at the time of presentation and men had slightly higher incidence of rupture at larger aneurysm size. Men were more likely to undergo EVAR, with significant differences in elective (82.1% vs. 74.1%, P = 0.01), but not ruptured repair. Women had significantly higher mortality rates following elective EVAR (3.1% vs. 0.6%, P = 0.01), but not after ruptured or elective open repair. Following elective EVAR, women were less likely to be discharged to home after longer hospital stays (3 vs. 2 days, P < 0.01).

CONCLUSIONS

Despite presentation at a similar age, with a smaller aneurysm diameter, and similar medical comorbidities, women experience substantially worse hospital outcomes primarily driven by elective endovascular procedures. Utilization of endovascular techniques in women still remains lower compared with men. Improvement of elective outcomes in women will likely depend on technical advancements in repair techniques and management strategies that may differ between genders.