Differences between women and men in surgical treatment and case fatality rates for ruptured aortic abdominal aneurysm in England

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.

Strategy of endovascular versus open repair for patients with clinical diagnosis of ruptured abdominal aortic aneurysm: the IMPROVE RCT

BACKGROUND

Ruptured abdominal aortic aneurysm (AAA) is a common vascular emergency. The mortality from emergency endovascular repair may be much lower than the 40-50% reported for open surgery.

OBJECTIVE

To assess whether or not a strategy of endovascular repair compared with open repair reduces 30-day and mid-term mortality (including costs and cost-effectiveness) among patients with a suspected ruptured AAA.

DESIGN

Randomised controlled trial, with computer-generated telephone randomisation of participants in a 1 : 1 ratio, using variable block size, stratified by centre and without blinding.

SETTING

Vascular centres in the UK (n = 29) and Canada (n = 1) between 2009 and 2013.

PARTICIPANTS

A total of 613 eligible participants (480 men) with a ruptured aneurysm, clinically diagnosed at the trial centre.

INTERVENTIONS

A total of 316 participants were randomised to the endovascular strategy group (immediate computerised tomography followed by endovascular repair if anatomically suitable or, if not suitable, open repair) and 297 were randomised to the open repair group (computerised tomography optional).

MAIN OUTCOME MEASURES

The primary outcome measure was 30-day mortality, with 30-day reinterventions, costs and disposal as early secondary outcome measures. Later outcome measures included 1- and 3-year mortality, reinterventions, quality of life (QoL) and cost-effectiveness.

RESULTS

The 30-day mortality was 35.4% in the endovascular strategy group and 37.4% in the open repair group [odds ratio (OR) 0.92, 95% confidence interval (CI) 0.66 to 1.28; p = 0.62, and, after adjustment for age, sex and Hardman index, OR 0.94, 95% CI 0.67 to 1.33]. The endovascular strategy appeared to be more effective in women than in men (interaction test p = 0.02). More discharges in the endovascular strategy group (94%) than in the open repair group (77%) were directly to home (p < 0.001). Average 30-day costs were similar between groups, with the mean difference in costs being -£1186 (95% CI -£2997 to £625), favouring the endovascular strategy group. After 1 year, survival and reintervention rates were similar in the two groups, QoL (at both 3 and 12 months) was higher in the endovascular strategy group and the mean cost difference was -£2329 (95% CI -£5489 to £922). At 3 years, mortality was 48% and 56% in the endovascular strategy group and open repair group, respectively (OR 0.73, 95% CI 0.53 to 1.00; p = 0.053), with a stronger benefit for the endovascular strategy in the subgroup of 502 participants in whom repair was started for a proven rupture (OR 0.62, 95% CI 0.43 to 0.89; p = 0.009), whereas aneurysm-related reintervention rates were non-significantly higher in this group. At 3 years, considering all participants, there was a mean difference of 0.174 quality-adjusted life-years (QALYs) (95% CI 0.002 to 0.353 QALYs) and, among the endovascular strategy group, a cost difference of -£2605 (95% CI -£5966 to £702), leading to 88% of estimates in the cost-effectiveness plane being in the quadrant showing the endovascular strategy to be 'dominant'.

LIMITATIONS

Because of the pragmatic design of this trial, 33 participants in the endovascular strategy group and 26 in the open repair group breached randomisation allocation.

CONCLUSIONS

The endovascular strategy was not associated with a significant reduction in either 30-day mortality or cost but was associated with faster participant recovery. By 3 years, the endovascular strategy showed a survival and QALY gain and was highly likely to be cost-effective. Future research could include improving resuscitation for older persons with circulatory collapse, the impact of local anaesthesia and emergency consent procedures.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN48334791 and NCT00746122.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 31. See the NIHR Journals Library website for further project information.

Persisting disparities between sexes in outcomes of ruptured abdominal aortic aneurysm hospitalizations

We sought to describe and analyze discrepancies between sexes in the outcomes of patients hospitalized for ruptured abdominal aortic aneurysms (rAAA) by conducting a retrospective analysis of the Nationwide Inpatient Sample. The review included all adult patients (≥18 years old) hospitalized with a primary diagnosis of rAAA between January 2002 and December 2014. In-hospital mortality differences between females and males were analyzed overall and separately among those receiving endovascular AAA repair (EVAR) or open AAA repair (OAR). In-hospital mortality for females declined from 61.0% in 2002 to 49.0% in 2014 (P for trend <0.001), while mortality for males declined from 48.6% in 2002 to 32.2% in 2014 (P for trend <0.001). Among those receiving EVAR, females were significantly more likely to die in the hospital than males (adjusted odds ratio [OR], 1.44; 95% CI, 1.12-1.84). In addition, the odds of mortality among those receiving OAR were higher for females than males (adjusted OR, 1.14; 95% CI: 1.00-1.31). These data provide evidence that despite overall decreasing trends in mortality for both sexes, females remain at higher risk of death compared with males regardless of surgical repair procedure.

Emerging strategies to treat ruptured abdominal aortic aneurysms

Population screening programmes and a falling population prevalence of smoking have led to a declining incidence of ruptured abdominal aortic aneurysms in men. However, ruptured abdominal aortic aneurysms remain a common vascular surgical emergency, with an increasing proportion of ruptures being in women. About one quarter of the ruptures have a juxta-renal aneurysm and are more challenging to repair using endovascular technologies. Endovascular technologies may not reduce the overall mortality, compared with open surgical repair, but appear to offer early benefits with respect to patient quality of life at acceptable cost. Challenges over the next 5 years include widening the access to repair, developing an accurate bedside risk scoring tool, as well as optimising strategies for pre-operative resuscitation, standardising peri-operative care and the management of post-operative complications.

Mortality from ruptured abdominal aortic aneurysms: clinical lessons from a comparison of outcomes in England and the USA

BACKGROUND

The outcome of patients with ruptured abdominal aortic aneurysm (rAAA) varies by country. Study of practice differences might allow the formulation of pathways to improve care.

METHODS

We compared data from the Hospital Episode Statistics for England and the Nationwide Inpatient Sample for the USA for patients admitted to hospital with rAAA from 2005 to 2010. Primary outcomes were in-hospital mortality, mortality after intervention, and decision to follow non-corrective treatment. In-hospital mortality and the rate of non-corrective treatment were analysed by binary logistic regression for each health-care system, after adjustment for age, sex, year, and Charlson comorbidity index.

FINDINGS

The study included 11,799 patients with rAAA in England and 23,838 patients with rAAA in the USA. In-hospital mortality was lower in the USA than in England (53·05% [95% CI 51·26-54·85] vs 65·90%; p<0·0001). Intervention (open or endovascular repair) was offered to a greater proportion of cases in the USA than in England (19,174 [80·43%] vs 6897 [58·45%]; p<0·0001) and endovascular repair was more common in the USA than in England (4003 [20·88%] vs 589 [8·54%]; p<0·0001). Postintervention mortality was similar in both countries (41·77% for England and 41·65% for USA). These observations persisted in age-matched and sex-matched comparisons. In both countries, reduced mortality was associated with increased use of endovascular repair, increased hospital caseload (volume) for rAAA, high hospital bed capacity, hospitals with teaching status, and admission on a weekday.

INTERPRETATION

In-hospital survival from rAAA, intervention rates, and uptake of endovascular repair are lower in England than in the USA. In England and the USA, the lowest mortality for rAAA was seen in teaching hospitals with larger bed capacities and doing a greater proportion of cases with endovascular repair. These common factors suggest strategies for improving outcomes for patients with rAAA.

FUNDING

None.

Transfer of patients with ruptured abdominal aortic aneurysm from general hospitals to specialist vascular centres: results of a Delphi consensus study

Aim

To explore areas of consensus and disagreement concerning the interhospital transfer of patients with a clinical diagnosis of ruptured abdominal aortic aneurysm.

Methods

A three-round Delphi questionnaire approach was used among vascular and endovascular surgery and emergency medicine specialists to explore patient characteristics and clinical management issues for emergency interhospital transfer. Analysis is based on 38 responses to rounds 2 and 3 (19 vascular surgeons, 6 interventional radiologists, 13 emergency care specialists) with agreement reported when 70% of respondents were in agreement.

Results

Initially there was agreement that transfer patients should be <85 years of age, either alert or with fluctuating consciousness, with moderate or minimal systemic disease, needing no/some help with daily living. Round 3 clarified that patients requiring inotropes and those institutionalised for mental infirmity should be transferred. Those with cardiac arrest in current episode should not be transferred. There was no agreement as to whether those institutionalised with physical infirmities, unconscious/intubated patients or those with severe systemic disease should be transferred. Speed was accepted as important, with agreement for specialty trainees to arrange transfer if consultants were not on site. Consultant–consultant discussion was recommended for patients with severe systemic disease. CT confirmation of diagnosis was considered unnecessary before transfer but ultrasound assessment was desirable, and transfers should not be delayed by waiting for specific tests. There was no agreement about blood tests and ECG before transfer or whether blood should accompany the patient being transferred. There was no agreement as to whether specific staff/facilities needed to be in place at the specialist hospital. A systolic blood pressure ≥70 mm Hg was sufficient for transfer without the need for intravenous fluids unless deterioration occurred.

Conclusions

There is broad agreement about the type of patient who should be eligible for transfer but disagreements about patient management before and during transfer remain.

Explaining the decrease in mortality from abdominal aortic aneurysm rupture

BACKGROUND

A steady rise in mortality from abdominal aortic aneurysm (AAA) was reported in the 1980s and 1990 s, although this is now declining rapidly. Reasons for the recent decline in mortality from AAA rupture are investigated here.

METHODS

Routine statistics for mortality, hospital admissions and procedures in England and Wales were investigated. All data were age-standardized. Trends in smoking, hypertension and treatment for hypercholesterolaemia (statins), together with regression coefficients for mortality, were available from public sources for those aged at least 65 years. Deaths from ruptured AAA avoided in this age group were estimated by using the IMPACT equation: deaths avoided = (deaths in index year) × (risk factor decline) × β-coefficient.

RESULTS

From 1997, deaths from ruptured AAA have decreased sharply, almost twofold in men. Hospital admissions for elective AAA repair have increased modestly (from 40 to 45 per 100,000 population), attributable entirely to more procedures in those aged 75 years and over (P < 0.001). Admissions for ruptured AAA have declined from 18.6 to 13.5 per 100,000 population, across all ages, with the proportion offered and surviving emergency repair unchanged. From 1997, mortality from ruptured aneurysm in those aged at least 65 years has fallen from 65.9 to 44.6 per 100,000 population. An estimated 8-11 deaths per 100,000 population were avoided by a reduced prevalence of smoking and a similar number from an increase in the number of elective AAA repairs. Estimates for the effects of blood pressure and lipid control are uncertain.

CONCLUSION

The reduction in incidence of ruptured AAA since 1997 is attributable largely to changes in smoking prevalence and increases in elective AAA repair in those aged 75 years and over.

Use of Hospital Episode Statistics to investigate abdominal aortic aneurysm surgery

BACKGROUND

A coding framework was evaluated to study patients undergoing open surgical replacement of an abdominal aortic aneurysm (AAA) in the English Hospital Episode Statistics (HES) database. The objective was to create groups of patients who are homogeneous with respect to diagnosis, prognosis and treatment.

METHODS

The frequency and consistency of potentially relevant diagnosis (International Classification of Diseases, 10th revision) and procedure (Office of Population Censuses and Surveys Classification, 4th revision) codes were assessed in patients admitted to English National Health Service hospitals between April 2003 and March 2008. Administrative codes were compared with diagnosis and procedure codes to check that patients who had undergone emergency surgery for a ruptured AAA were admitted as an emergency.

RESULTS

Of 20 290 patients undergoing AAA replacement, 19 250 (94·9 per cent) had a consistent diagnosis (unruptured or ruptured AAA); 79·3 per cent of patients with an emergency replacement were coded as having a ruptured AAA and 95·7 per cent of those with a non-emergency replacement as having an unruptured AAA. Of patients who had undergone emergency replacement of a ruptured AAA, 93·3 per cent were coded as having been admitted as an emergency.

CONCLUSION

Coding consistency was high. The proposed framework could define homogeneous groups by combining diagnosis, procedure and administrative codes. It also allows an assessment of potential miscoding at national and hospital level.

Outcome after open repair of ruptured abdominal aortic aneurysm in patients>80 years old: a systematic review and meta-analysis

BACKGROUND

The role of open repair in the management of ruptured abdominal aortic aneurysm (RAAA) in patients>80 years old is questioned by the perceived high operative risk of these patients. This issue has been investigated in the present meta-analysis of observational studies.

METHODS

Studies on open repair of RAAA in patients>80 years old were identified in July 2010. The immediate and intermediate results were expressed as pooled proportions with 95% confidence interval (95% CI). Linear regression and meta-regression were performed to evaluate the impact of variables on the immediate postoperative mortality.

RESULTS

Pooled analysis of 29 studies showed that the risk of immediate postoperative mortality in patients>80 years old was significantly higher than in younger patients (risk ratio 1.440, 95%CI 1.365-1.519, I2 36.8%, P=0.002; risk difference 19.4%, 95% CI 16.4-22.4%, I2 38.8%, P=0.019). Pooled analysis of 36 studies showed an immediate postoperative mortality rate of 59.2% (95% CI 55.7-62.5, I2 35.62). Immediate postoperative mortality in patients<80 years old positively correlated with that of patients>80 years old (rho: 0.686, P<0.0001). Intermediate survival data of 111 operative survivors were available from six studies, and their pooled survival rates at 1-, 2-, and 3-year were 82.4, 75.6, and 68.7%, respectively.

CONCLUSIONS

Immediate and intermediate survival rates of patients>80 years old after open repair of RAAA are acceptable. These findings suggest a more confident approach toward emergency repair of RAAA in the very elderly.

All-cause mortality after first ERCP in England: clinically guided analysis of hospital episode statistics with linkage to registry of death

BACKGROUND

All-cause death within 30 days of ERCP is a candidate indicator of care, but institutional-level statistics require careful interpretation. National-scale, population-based outcome studies of unselected patients undergoing ERCP are needed to define expected levels of real-world mortality risk and the case-mix factors that predict poor outcome.

OBJECTIVE

To develop methods for analyzing administrative data for English hospitals with linkage to death registration to study all-cause mortality after first ERCPs and explore predictors of death and institutional variation.

DESIGN

Hospital episode statistics for 2006 to 2007 and 2007 to 2008 were linked to the statutory death register. First ERCP episodes were extracted and analyzed for demographic characteristics, admission method, diagnoses, and comorbidities. Additional linkages identified the last-coded diagnosis before death. Factors associated with 30-day death were identified by univariate and multiple logistic analyses. Pilot data and a survey were sent to clinicians at each institution. Crude and case-mix adjusted mortality were analyzed at the institutional level.

MAIN OUTCOME MEASUREMENTS

Death within 30 days of the first ERCP procedure.

RESULTS

We analyzed 20,246 first ERCPs from 2006 to 2007 and 20,422 from 2007 to 2008. Diagnostic profile: gallstone related 57.3%; cancer 12.6%; gallstone and cancer 2%; others 28.1%. All-cause 30-day death was 5.3% (2.4% in non-cancer cases). Predictors of 30-day death (adjusted odds ratio [OR]) were as follows: age (OR 6.2, for ≥85 years vs <55 years), male sex (OR 1.2 vs female), emergency admission (OR 2.0 vs elective), cancer (OR 8.6 vs no cancer), and non-cancer comorbidity (OR 1.5 vs none). A mortality risk estimator (look-up table) based on pooled data for >40,000 first ERCPs is provided. Specific procedural complication codes were identified in 1.2% of deaths (0.06% of ERCPs). At the institutional level, analysis of mortality rates was within expected statistical funnel limits, and we found no correlation with ERCP volume (Pearson r = -0.05; P > .05).

LIMITATIONS

The completeness and accuracy of coding may vary between different hospitals. Routine coding does not capture information about procedural complexity or severity of illness.

CONCLUSION

Linkage analysis of hospital episode statistics data for England provides a powerful tool for studying mortality risk after ERCP on an unselected and truly nationwide scale. Institutional-level statistics suggest that the mortality risk for patients requiring ERCP was comparable across English hospitals.

Systematic review and meta-analysis of sex differences in outcome after intervention for abdominal aortic aneurysm

Background

The aim of this study was to assess possible differences in mortality between men and women with an abdominal aortic aneurysm (AAA) treated either by elective repair or following aneurysm rupture.

Methods

A systematic literature search was performed using the MEDLINE, Cochrane and Embase databases. Data were analysed by means of bivariate random-effects meta-analysis. Data were pooled and odds ratios (ORs) calculated for women compared with men.

Results

Sixty-one studies (516 118 patients) met the predetermined inclusion criteria. Twenty-six reported on elective open AAA repair, 21 on elective endovascular repair, 25 on open repair for ruptured AAA and one study on endovascular repair for ruptured AAA. Mortality rates for women compared with men were 7·6 versus 5·1 per cent (OR 1·28, 95 per cent confidence interval (c.i.) 1·09 to 1·49) for elective open repair, 2·9 versus 1·5 per cent (OR 2·41, 95 per cent c.i. 1·14 to 5·15) for elective endovascular repair, and 61·8 versus 42·2 per cent (OR 1·16, 95 per cent c.i. 0·97 to 1·37) in the group that had open repair for rupture. The group that had endovascular repair for ruptured AAA was too small for meaningful analysis.

Conclusion

Women with an AAA had a higher mortality rate following elective open and endovascular repair.

Outcome from abdominal aortic aneurysms in Scotland, 1991-2006

BACKGROUND

This study assessed the impact of sex, presentation and treatment on outcome from abdominal aortic aneurysm (AAA) in Scotland.

METHODS

All patients admitted from January 1991 to December 2006 with a primary diagnosis of AAA were identified. Patients were stratified by age, sex, admission diagnosis (ruptured versus intact) and procedure performed (endovascular versus open repair). Multivariable logistic regression analysis was used to determine predictors of mortality.

RESULTS

Some 9779 men and 2927 women were admitted with a principal diagnosis of AAA. Women were significantly older than men (median (range) age 75 (35-97) versus 71 (17-96) years; P < 0.001). A higher proportion of women presented with a ruptured AAA (29.5 versus 27.5 per cent; P = 0.043). Age (odds ratio (OR) 2.52 (95 per cent confidence interval 2.36 to 2.74); P < 0.001), female sex (OR 1.63 (1.48 to 1.78); P < 0.001) and admission diagnosis (OR 10.49 (9.53 to 11.54); P < 0.001) were independent predictors of early death, whereas endovascular repair predicted survival (OR 0.67 (0.58 to 0.76); P < 0.001).

CONCLUSION

Women presenting with an AAA were older and more likely to be admitted with a ruptured aneurysm. Female sex was an independent risk factor for death from AAA.

Abdominal aortic aneurysm in women: Prevalence, risk factors, and implications for screening

OBJECTIVE

Accurate data regarding the prevalence and associated risk factors for aneurysmal disease is essential when determining the appropriateness of screening for abdominal aortic aneurysms (AAA). Although women are poorly represented in most large studies of AAA prevalence, the US Preventative Services Task Force recently recommended against primary screening for AAA in women. The purpose of this analysis was to define the prevalence and risk factors associated with the development of AAA in women.

METHODS

A free duplex ultrasound screening was offered to men and women with cardiovascular risk factors or a family history of AAA. Patients were recruited through advertising at local screening centers and screenings were performed between 2004 and 2006. Demographic information and cardiovascular and aneurysmal disease risk factors were obtained for each patient through a questionnaire. A total of 17,540 subjects were screened for AAA, including 10,012 women (mean age 69.6 years) and 7528 men (mean age 70.0 years). Univariate and multivariable logistic regression analysis was performed on the subset of women that were screened to determine risk factors for and prevalence of AAA.

RESULTS

Seventy-four aneurysms were detected in women (including four aneurysms >5 cm diameter and 70 aneurysms 3 to 5 cm diameter) while 291 were detected in men, resulting in prevalence rates of 0.7% and 3.9%, respectively. Increasing age (odds ratio [OR]= 4.57, 95% confidence interval [CI] 1.98 to 10.54, P < .0001), history of tobacco use (OR = 3.29, 95% CI 1.86 to 5.80, P < .0001), and cardiovascular disease (OR= 3.57, 95% CI 2.19 to 5.84, P < .0001) were independently associated with AAA in women on univariate and multivariable analysis. Women with multiple atherosclerotic risk factors were more commonly found to have AAAs and had a prevalence rate of AAA as high as 6.4%.

CONCLUSION

Although the medical literature suggests a low prevalence rate of AAA in women in the general population, specific risk factors are associated with the development of AAA, and subgroups of women can be identified that are at a substantially increased risk of aneurysmal disease. In particular, elevated rates of AAA were found among women of advanced age (> or =65 years) with a history of smoking or heart disease. These data support the notion that women with such risk factors should be considered for AAA screening.