Trends in mortality and hospital admission rates for abdominal aortic aneurysm in England and Wales, 1979-1999

BACKGROUND: The aim of this study was to investigate trends in population-based mortality, hospital admission and case fatality rates for abdominal aortic aneurysm (AAA) from 1979 to 1999. METHODS: This was an analysis of routine statistics from 79 495 death certificates in England and Wales and 3217 hospital inpatient admissions in the Oxford Region. RESULTS: Mortality rates for all AAAs increased between 1979 and 1999 from 13 to 25 per million in women and from 80 to 115 per million in men. Admission rates increased in the same time interval from three to 22 admissions per million per year in women, and from 52 to 149 per million per year in men. Case fatality rates for all non-ruptured AAAs that were operated on decreased from 25.8 to 9.0 per cent and for all ruptured AAAs from 69.9 to 54.4 per cent. CONCLUSION: Mortality rates and hospital admission rates for AAA rose in men and even more so in women between 1979 and 1999. Perioperative mortality for ruptured AAA declined a little during the study but nonetheless was still very high at the end. This reinforces the importance of detecting and treating AAA before rupture occurs.     

Influence of gender on outcome from ruptured abdominal aortic aneurysm

BACKGROUND: The aim of the present study was to compare outcomes following ruptured abdominal aortic aneurysm (AAA) in men and women. METHODS: Overall mortality from ruptured AAA was compared in men and women using the Western Australia Health Services Research Database. The linked chains of de-identified hospital morbidity and death records were selected using the ICD-9-CM (International Classification of Diseases - Clinical Modification) diagnostic and procedure codes pertaining to AAA. Cases were divided into three groups for analysis: patients who died without admission to hospital, those admitted to hospital with a ruptured AAA but who did not undergo operation, and patients who underwent operation for ruptured AAA. RESULTS: Ruptured AAA occurred in 648 men and 225 women over the age of 55 years during the decade 1985-1994. Only 50 per cent of women, compared with 59 per cent of men, were admitted to hospital. Of those admitted to hospital only 37 per cent of women underwent operation, compared with 63 per cent of men. The overall mortality rate from ruptured AAA was 90 per cent in women and 76 per cent in men (chi2 = 50.34, 1 d.f., P < 0.0001). Although women were, on average, 6 years older than men, this unfavourable pattern occurred across all age groups. CONCLUSION: Women with a ruptured AAA are more likely to die than men. More research is required to identify the causes of this sex difference.     

Predictors of repair and effect of gender on treatment of ruptured abdominal aortic aneurysm

OBJECTIVE: The purpose of this study was to determine factors associated with increased likelihood of patients undergoing surgery to repair ruptured abdominal aortic aneurysms (AAAs). Specifically, we investigated whether men were more likely than women to be selected for surgery after rupture of AAAs. METHODS: All patients with a ruptured AAA who came to a hospital in Ontario between April 1, 1992, and March 31, 2001, were included in this population-based retrospective study. Administrative data were used to identify patients, patient demographic data, and hospital variables. RESULTS: Crude 30-day mortality for the 3570 patients who came to a hospital with a ruptured AAA was 53.4%. Of the 2602 patients (72.9%) who underwent surgical repair, crude 30-day mortality was 41.0%. Older patients (odds ratio [OR], 0.649 per 5 years of age; P<.0001), with a higher Charlson Comorbidity Index (OR, 0.848; P<.0001), were less likely to undergo AAA repair. Patients treated at high-volume centers (OR, 2.674 per 10 cases; P<.0001) and men (OR, 2.214; P<.0001) were more likely to undergo AAA repair. CONCLUSION: Men are more likely to undergo repair of a ruptured AAA than women are, for reasons that are unclear. Given the large magnitude of the effect, further studies are clearly indicated.     

Glasgow Aneurysm Score as a predictor of immediate outcome after surgery for ruptured abdominal aortic aneurysm

BACKGROUND: The aim of the study was to assess the value of the Glasgow Aneurysm Score in predicting postoperative death after repair of a ruptured abdominal aortic aneurysm (AAA). METHODS: Between 1991 and 1999, 836 patients underwent surgery for ruptured AAA. Their operative risk at presentation was evaluated retrospectively using the Glasgow Aneurysm Score, based on data from the nationwide Finnvasc registry. RESULTS: The operative mortality rate was 47.2 per cent (395 of 836); 164 patients (19.6 per cent) had cardiac complications and 164 (19.6 per cent) required intensive care treatment for more than 5 days. Predictors of postoperative death in univariate analysis were: coronary artery disease (P = 0.005), preoperative shock (P < 0.001), age (P < 0.001), and the Glasgow Aneurysm Score (P < 0.001). In multivariate analysis the predictors were: preoperative shock (odds ratio (OR) 2.13 (95 per cent confidence interval (c.i.) 1.45 to 3.11); P < 0.001) and the Glasgow Aneurysm Score (for an increase of ten units: OR 1.81 (95 per cent c.i. 1.54 to 2.12); P < 0.001). Receiver-operator characteristic (ROC) curves showed that the best cut-off value of the Glasgow Aneurysm Score in predicting postoperative death was 84 (area under the curve 0.75 (95 per cent c.i. 0.72 to 0.78), standard error 0.17; P < 0.001). The operative mortality rate was 28.2 per cent (114 of 404) in patients with a Glasgow Aneurysm Score of 84 or less, compared with 65.0 per cent (281 of 432) in those with a score greater than 84 (P < 0.001). CONCLUSION: The Glasgow Aneurysm Score predicted postoperative death after repair of ruptured AAA in this series.     

The impact of gender on presentation, therapy, and mortality of abdominal aortic aneurysm in the United States, 2001-2004

INTRODUCTION: The elective repair of abdominal aortic aneurysms (AAA) may decrease a patient's risk of rupture and confers a significantly lower in-hospital mortality rate than emergency repair. Previous works have shown that AAA rupture rates are higher in women compared to men, and that women have higher associated in-hospital mortality rates. This study was performed to evaluate, currently, to what extent patient gender influences presentation and treatment of AAA and the associated outcomes in the United States. METHODS: The Nationwide Inpatient Sample was used, with pertinent ICD-9 codes, to identify all patient-discharges that occurred with the primary diagnosis of intact (iAAA) or ruptured/dissecting (rAAA) abdominal aortic aneurysms between the years 2001 and 2004. Univariate and multiple logistic regression analyses of variables were performed. RESULTS: An estimated 220,403 AAA patient-discharges were identified during the study period. 37,016 (17%) patients presented with rAAA. A higher percentage of women with AAA presented with rupture compared to men (21% vs 16%; odds ratio [OR] 1.40, 95% confidence interval [CI], 1.27-1.54). This rupture rate did not significantly change from 2001 to 2004 (P = .85 for trend). For iAAA, women had higher odds of in-hospital mortality than men (OR 1.60; 95% CI, 1.24-2.07). Compared to men, in-hospital mortality rates for women with iAAA were higher for both endovascular (2.1% vs 0.83%, P < .0001) and open repairs (6.1% vs 4.0%, P < .0001). For iAAA, fewer women underwent endovascular repair (32.4% vs 46.7%, P < .0001; O.R. 0.59, 95% CI, 0.52-0.67). For patients who presented with rAAA, women were less likely to undergo surgical intervention compared to men (59% vs 70%, P < .0001). For those that underwent repair, women had higher in-hospital mortality rates than men (43% vs 36%, P < .0001; OR 1.49, 95% CI, 1.16-1.91). CONCLUSION: A higher percentage of women currently present with aneurysm rupture. They have higher in-hospital mortality rates for both iAAA and rAAA. This gender difference in the outcomes following repair of abdominal aortic aneurysm has persisted over time, the cause of which is not explained by these or previous data, a fact that warrants further investigation.     

Abdominal aortic aneurysms in the New Zealand Maori population

BACKGROUND: Abdominal aortic aneurysm (AAA) is believed to be a rare disease in people of non-European descent. Maori, New Zealand's indigenous people, are thought to originate from South East Asia, so their incidence of AAA might also be expected to be low. The aim was to investigate the incidence and phenotypic factors associated with AAA in the New Zealand Maori population. METHODS: A retrospective study was performed using the audit database of the New Zealand Society of Vascular Surgeons. Age-standardized rates of admission and death were calculated for Maori and non-Maori. RESULTS: Maori comprised 3.9 per cent of the population who had an AAA repaired, similar to the percentage of the Maori population aged over 65 years. However, the death rate from AAA in Maori was 2.4 times the rate in non-Maori. Maori were younger at diagnosis than non-Maori (65.2 versus 71.8 years; P < 0.001), had more emergency procedures (46.6 versus 30.2 per cent; P = 0.018) and a significantly higher proportion of Maori admissions were for a ruptured aneurysm. CONCLUSION: Maori had a higher mortality rate from AAA than non-Maori New Zealanders. Although admission rates between Maori and non-Maori were similar, the earlier age of onset and the increased proportion of ruptured aneurysms may indicate that the disease is more severe in Maori.     

Quantification of mortality risk after abdominal aortic aneurysm repair

BACKGROUND: The study was designed to evaluate the Acute Physiology And Chronic Health Evaluation (APACHE) II risk scoring system in abdominal aortic aneurysm (AAA) surgery. The aim was to create an APACHE-based risk stratification model for postoperative death. METHODS: Prospective postoperative APACHE II data were collected from patients undergoing AAA repair over a 9-year interval from 24 intensive care units (ICUs) in the Thames region. A multilevel logistic regression model (APACHE-AAA) for in-hospital mortality was developed to adjust for both case mix and the variation in outcome between ICUs. RESULTS: A total of 1896 patients were studied. The in-hospital mortality rate among the 1289 patients who had elective AAA repair was 9.6 (95 per cent confidence interval (c.i.) 8.0 to 11.2) per cent and that among the 605 patients who had an emergency repair was 46.9 (95 per cent c.i. 43.0 to 50.9) per cent. Four independent predictors of death were identified: age (odds ratio (OR) 1.05 (95 per cent c.i. 1.03 to 1.07) per year increase), Acute Physiology Score (OR 1.14 (95 per cent c.i. 1.12 to 1.17) per unit increase), emergency operation (OR 4.86 (95 per cent c.i. 3.64 to 6.52)) and chronic health dysfunction (OR 1.43 (95 per cent c.i. 1.04 to 1.97)). The APACHE-AAA model was internally valid, as shown by calibration (Hosmer-Lemeshow C statistic: chi(2) = 6.14, 8 d.f., P = 0.632), discrimination properties (area under receiver-operator characteristic curve 0.845) and subgroup analysis. There was no significant variation in outcome between hospitals. CONCLUSION: APACHE-AAA was shown to be an accurate risk-stratification model that could be used to quantify the risk of death after AAA surgery. It might also be used to determine the relative impact of ICU over high-dependency unit care.     

Epidemiological study of the relationship between volume and outcome after abdominal aortic aneurysm surgery in the UK from 2000 to 2005

BACKGROUND: The aim was to assess the relationship between hospital volume and outcome after abdominal aortic aneurysm (AAA) surgery in the UK. METHODS: Hospital Episode Statistics (2000-2005) were classified as elective, urgent or ruptured AAA repair. Analysis was by modelling of mortality rate, complication rate and length of hospital stay with regard to the annual operative volume, after risk adjustment. RESULTS: There were 112,545 diagnoses, or repairs, of AAAs, of which 26,822 were infrarenal aneurysms. The mean mortality rate was 7.4, 23.6 and 41.8 per cent for elective, urgent and ruptured AAA repair respectively. Elective AAA repair undertaken at high-volume hospitals showed volume-related improvements in mortality (P < 0.001). Patients were discharged from hospital earlier (P < 0.001). The critical volume threshold was 32 elective AAA repairs per year. For urgent repair, patients at high-volume hospitals had a reduced mortality rate (P = 0.017) with an increased length of stay (P = 0.041). There was no relationship between volume and outcome for ruptured AAA repairs. CONCLUSION: Increased annual volumes were associated with significant reductions in mortality for elective and urgent AAA repair, but not for repair of ruptured AAAs.     

Validity of the Glasgow Aneurysm Score and the Hardman Index in predicting outcome after ruptured abdominal aortic aneurysm repair

BACKGROUND: The Glasgow Aneurysm Score and the Hardman Index have been recommended as predictors of outcome after repair of ruptured abdominal aortic aneurysm (AAA). This study aimed to assess their validities. METHODS: Patients admitted to a single unit with a ruptured AAA over a 2-year interval (2000-2001) were identified from a prospectively compiled database. Hospital records of all patients undergoing attempted operative repair were reviewed. The Glasgow Aneurysm Score and the Hardman Index were calculated retrospectively and related to clinical outcome. RESULTS: One hundred patients were admitted with a ruptured AAA. Of these, 82 underwent attempted operative repair and were included in the study: 68 men and 14 women, of median age 73 (range 54-87) years. Thirty (37 per cent) patients died after the operation. The Glasgow Aneurysm Score was a poor predictor of postoperative mortality. The area under the Receiver-Operator Characteristic curve was 0.606 (P = 0.112, 95 per cent c.i. 0.483-0.729). Similarly, the Hardman Index failed to predict postoperative mortality accurately (P = 0.211, chi(2) for trend). Of nine patients in this series with three or more Hardman criteria, generally held to be fatal, six survived. CONCLUSION: Contrary to previous reports, The Glasgow Aneurysm Score and the Hardman Index were poor predictors of postoperative mortality after repair of a ruptured AAA in this study.     

Different disease profiles for women and men with abdominal aortic aneurysms.

OBJECTIVE: The overall aim with this study was to investigate causes of death and mortality rates for women and men treated for abdominal aortic aneurysm (AAA) in Sweden. MATERIALS AND METHOD: All patients treated for ruptured and non-ruptured AAA 1987-2002 in Sweden were identified in national registries (n=12917). Age, sex, diagnosis, surgical procedure and mortality were analysed on a patient specific level. Logistic regression and analysis of standardised mortality rates (SMR) were performed. RESULTS: Post operative mortality was similar between the sexes. Age (p<0.0001), and surgery for rupture (p=0.0005), but not gender (p=0.65) were significant risk factor for poor long term survival. SMR revealed increased risk for both sexes compared to the population with significantly higher values for women than men (2.26, CI 2.10-2.43 vs. 1.63, CI 1.57-1.68, p<0.0001). The higher risk for women could be explained by the higher risk for aneurysm related death (ie.thoracic or abdominal aorta) compared to men (Hazard ratio 1.57 vs. 1.0, p<0.0001). CONCLUSION: Women do not have an increased surgical risk compared to men, but treated women have an increased risk of premature death compared to men and women in the population. They also have a higher risk for aneurysm related death compared to men with AAA.     

Randomized clinical trial of screening for abdominal aortic aneurysm in women

BACKGROUND: Screening for abdominal aortic aneurysm (AAA) is commonly restricted to men. Recent studies have indicated a possible increase in deaths due to ruptured AAA in women, and a higher rate of rupture in women than in men. The present report details results from a randomized controlled trial that assessed the effects of screening women for AAA. METHODS: Some 9342 women aged 65-80 years were entered into the trial and randomized to age-matched screen and control groups. A single ultrasonographic scan was offered to women in the screening arm of the study. Women with an AAA received follow-up scans, and were considered for elective surgery if certain criteria were met. RESULTS: The prevalence of AAA was six times lower in women (1.3 per cent) than in men (7.6 per cent). Over 5- and 10-year follow-up intervals, the incidence of rupture was the same in the screened and control groups of women. CONCLUSION: Screening women for AAA is neither clinically indicated nor economically viable.     

Operative mortality rates for intact and ruptured abdominal aortic aneurysms in Michigan: An eleven-year statewide experience

Purpose: The purposes of this study were (1) to determine the current population-based mortality rate for the surgical treatment of abdominal aortic aneurysms (AAA) in Michigan, (2) to document changes in mortality rates over 11 years, and (3) to identify risk factors for operative mortality.Methods: A statewide database provided clinical information on all Michigan hospital admissions with a diagnosis of AAA from 1980 to 1990. The mortality rate analysis included all admissions with a primary diagnosis of AAA that underwent repair. Determination of diagnoses and comorbidities were based on International Classification of Diseases-ninth revision-Clinical Modification codes.Results: Conventional surgical repairs were performed on 8185 intact and 1829 ruptured AAA. Hospital mortality rates accompanying operation for intact AAA decreased from 13.6% in 1980 to 5.6% in 1990 (p < 0.001). Mortality rates over the 11 years averaged 10.7% in women and 6.8% in men (p < 0.001). Mortality rates averaged 10.7% in 4170 admissions of patients 70 years old or older and 4.2% in 4015 admissions of patients 69 years old or younger. Preexistent kidney failure was associated with an average mortality rate of 41.2% compared with 6.2% without this comorbidity. Preexistent dysrhythmia increased mortality rates from 6.6% to 13.6%. Uncomplicated hypertension, cerebrovascular disease, chronic obstructive pulmonary disease, diabetes, arterial occlusive disease, and ischemic heart disease in recent years were not associated with increased mortality rates. Hospitals with an annual volume of 21 or more intact AAA repairs had a surgical mortality rate of 6.2%, compared with 8.9% in hospitals with lower surgical volume (p < 0.001). Mortality rates for surgical repair of ruptured AAA averaged 49.8% and did not improve significantly over the 11 years studied.Conclusion: Despite a dramatic drop in surgical mortality rates, repair of intact AAA remains a formidable undertaking. This population-based series documents a substantially higher mortality rate than most selected series. The unchanged mortality rate for ruptured AAA suggests that development of better algorithms to identify those AAA most apt to rupture and earlier intervention in those instances is likely to improve patient survival rates. (J VASC SURG 1994;19:804-17.)     

Twelve-year experience of the management of ruptured abdominal aortic aneurysm

Background The operative mortality rate for elective repair of asymptomatic abdominal aortic aneurysm (AAA) is falling but the fate of patients with ruptured AAA may have changed little over the past decade. Methods This study was an analysis of a prospectively gathered computerized database. Results In the 12 years to 31 December 1994, 1144 patients underwent (attempted) repair of AAA. In 514 patients (44·9 per cent) who had an operation for ruptured AAA there was no significant change in the mean age, male: female ratio (418:96), or operative mortality rate (35·0 per cent) over the interval of the study. Forty-seven patients died before reaching the operating theatre, giving an ‘intention to operate’ mortality rate of 405 per cent. A further 68 patients (10·8 per cent of all patients who presented with a ruptured AAA) were not offered operation because of poor medical condition (n = 34) or extreme age (n = 34); three patients refused operation. A greater proportion of patients had surgery between 1989 and 1994 (276 of 323, 85·4 per cent) than between 1983 and 1988 (238 of 309, 77·0 per cent) (P <0·01, X² test). Conclusion The proportion of aneurysms operated on for rupture in this unit remains high (almost 50 per cent). The results of surgery for ruptured AAA have not improved in the past 12 years.     

Feasibility of preoperative computer tomography in patients with ruptured abdominal aortic aneurysm: a time-to-death study in patients without operation

INTRODUCTION: Despite advances in surgery, anaesthesia, and critical care, mortality from ruptured abdominal aortic aneurysms (AAAs) has not decreased over the last 20 years. Endovascular aneurysm repair (EVAR) of ruptured AAAs is an alternative to open repair, which may improve outcome. However, a computed tomography (CT) scan is usually required to assess the anatomic suitability of the aneurysm for EVAR. This may result in delay in transferring patients to the operating room. We evaluated all patients admitted to hospital with a ruptured AAA who died without undergoing surgery, to determine time to death after AAA rupture and thus the potential time available for obtaining a CT scan. METHODS: A retrospective case note review was conducted of 56 patients admitted to a single center with ruptured AAAs who did not undergo surgery because of advanced age or associated comorbidity over 8 years from 1995 to 2003. Statistical analysis was performed with the Fisher exact test. RESULTS: The 56 patients (33 men, 59%; 23 women, 41%) had a median age of 85 years (range, 71-98 years). Reasons for no operation being performed were shock (9%), cardiac arrest (11%), quality of life (29%), malignancy (7%), cardiac disease (15%), respiratory disease (16%) and age (14%). Median systolic blood pressure at admission was 110 mm Hg, heart rate was 88 beats per minute, and hemoglobin concentration was 10.5 g/dL. Patients were not aggressively resuscitated once a decision was made to not perform surgery. Death within 2 hours of hospital admission occurred in 7 (12.5%) patients, and 49 (87.5%) patients died more than 2 hours after admission. Median interval between onset of symptoms and admission to hospital was 2 hours 30 minutes (range, 44 minutes-36 hours), and the median interval between admission and death was 10 hours 45 minutes (range, 1 hour 1 minute-143 hours 55 minutes). The median total time to death from onset of symptoms was 16 hours 38 minutes (range, 2 hours 6 minutes-146 hours 50 minutes). CONCLUSION: Most (87.5%) patients admitted to hospital with a ruptured AAA died after more than 2 hours. These data show that most patients with a ruptured AAA who reach the hospital alive are sufficiently stable to undergo CT and consideration of EVAR.     

Meta-analysis and systematic review of the relationship between volume and outcome in abdominal aortic aneurysm surgery

BACKGROUND: This study investigated the volume-outcome relationship for abdominal aortic aneurysm (AAA) surgery and quantified critical volume thresholds. METHODS: PubMed, EMBASE and the Cochrane library were searched for articles on the operation volume-outcome relationship in elective and ruptured AAA surgery. UK Hospital Episode Statistics data were also considered. Elective and ruptured AAA repairs were dealt with separately. The data were meta-analysed, and the odds ratios (95 per cent confidence interval) for mortality at higher- and lower-volume hospitals were compared. Volume thresholds were identified from each paper. RESULTS: The analysis included 421,299 elective and 45,796 ruptured AAA operations. Significant relationships between mortality and annual volume were noted for both groups. Overall, the weighted odds ratio was 0.66 (0.65 to 0.67) for elective repair at a threshold of 43 AAAs per annum and 0.78 (0.73 to 0.82) for ruptured aneurysm repair at a threshold of 15 AAAs per annum, both in favour of high-volume institutions. CONCLUSION: Higher annual operation volumes are associated with significantly lower mortality in both elective and ruptured AAA repair. This suggests that AAA surgery should be performed only at higher-volume centres.     

To what extent has endovascular aneurysm repair influenced abdominal aortic aneurysm management in the state of Illinois?

PURPOSE: This study was performed using population-based data to determine the changing trends in the techniques for abdominal aortic aneurysm (AAA) repair in the state of Illinois during the past 9 years and to examine the extent to which endovascular aneurysm repair (EVAR) has influenced overall AAA management. METHODS: All records of patients who underwent AAA repair (1995 to 2003 inclusive) were retrieved from the Illinois Hospital Association COMPdata database. The outcome as determined by in-hospital mortality was analyzed according to intervention type (open vs EVAR) and indication (elective repair vs ruptured AAA). Data were stratified by age, gender, and hospital type (university vs community setting) and then analyzed using both univariate (chi 2 , t tests) and multivariate (stepwise logistic regression) techniques. RESULTS: Between 1995 and 2003, 14,517 patients underwent AAA repair (85% for elective and 15% for ruptured AAA). The average age was 71.4 +/- 7.9 years, and 76% were men. For elective cases, open repair was performed in 86% and EVAR in 14%; and for ruptured cases, open repair in 97% and EVAR in 3%. Elective EVAR was associated with lower in-hospital mortality compared with open repair regardless of age. No differences were observed with age after either type of repair for a ruptured aneurysm. Men had a lower in-hospital mortality compared with women for open repair of both elective and ruptured aneurysms. For EVAR, the mortality of an elective repair was lower in men, but there was no difference after a ruptured AAA. In men, the difference in mortality between elective open repair and EVAR was significant; the type of institution did not influence outcome. Patients >80 years of age had a higher mortality after open repair for both elective and ruptured AAA and after EVAR of a ruptured AAA. The average length of stay was 9.9 days for open elective repair, 13.1 days after open repair of a ruptured AAA, and 3.6 days for EVAR. The independent predictors of higher in-hospital mortality were female gender, age >80 years, diagnosis (ruptured vs open), and procedure (open vs EVAR). The year of the procedure and type of hospital (university vs community) were not predictive of outcome. CONCLUSIONS: EVAR has had a significant impact on AAA management in Illinois over a relatively short time period. In this population-based review, EVAR was associated with a significantly decreased in-hospital mortality and length of stay. Octogenarians had higher mortality after both types of repair, with the exception of elective EVAR.     

A decade of change in abdominal aortic aneurysm repair in the United States: Have we improved outcomes equally between men and women?

OBJECTIVES: Abdominal aortic aneurysm (AAA) repair has undergone vast changes in the last decade. We reviewed a national database to evaluate the effect on utilization of services and rupture rates. METHODS: From the Centers for Medicare Services (CMS), a 5% inpatient sample was obtained for 1994 to 2003 as beneficiary encrypted files (5% BEF) and as a limited data set file after 2001. Files were translated into Microsoft Access by using a custom program. Queries were performed using International Classification of Diseases (9th Revision) (ICD-9) diagnosis codes 441.3 (ruptured AAA) or 441.4 (non-ruptured AAA) and ICD-9 procedure codes 38.34, 38.36, 38.44, 38.64, 39.25, 39.52 for open, and 39.71 (available after October 2000) for endovascular repair. The 5% BEF totals were multiplied by 20 to calculate yearly volumes. Total cases were divided into the yearly CMS population of elderly Medicare recipients for repair rates per capita and are reported as cases per 100,000 elderly Medicare recipients. Statistics were performed using chi2, Student's t test, nonparametric tests, and multiple regression analysis; P < or = .05 was considered significant. RESULTS: Elective AAA repairs declined from 94.4/100,000 in 1994 to 87.7/100,000 in 2003. AAA rupture surgery declined from 18.7/100,000 (1994) to 13.6/100,000 (2003). Rupture repairs from 1994 to 2003 decreased by 29% for men and by 12% for women (P < .001). Rupture mortality has not changed, but the average is significantly higher for women at 52.8%, with men averaging 44.2% (P < .001). Mortality for elective AAA repair has decreased from 5.57% (1994) to 3.20% (2003) in men (P < .001) and from 7.48% (1994) to 5.45% (2003) in women (P < .001). Multivariate analysis demonstrated increasing age, female sex, and open surgery (vs endovascular) were significant predictors of elective and ruptured AAA repair mortality. For 2003 elective AAA repairs, the average length of stay was 6.9 days in men and 8.9 days in women (P < .01) For 2003, men were more likely to be discharged to home after rupture (32.9% of men vs 23.3% of women; P < .001) and elective repair (84.5% of men vs 70.1% of women; P < .001). CONCLUSIONS: Improvements in AAA management in the last decade have decreased aneurysm-related deaths and reduced the incidence of aneurysm ruptures, with a lower utilization of services. Women, however, continue to have a consistently higher mortality for open and ruptured AAA repair and are less likely to return to home after either.     

Mortality from ruptured abdominal aortic aneurysm in Wales.

BACKGROUND: The aim of this study was to identify the incidence of, and mortality in, patients with a ruptured abdominal aortic aneurysm (AAA) reaching hospital alive in Wales. METHODS: Patients who presented with a ruptured AAA between September 1996 and August 1997 were analysed. Data were collected prospectively by an independent body, observing strict confidentiality. RESULTS: Some 233 patients with a confirmed ruptured AAA were identified, giving an incidence of eight per 100 000 total population. Some 133 patients (57 per cent) underwent attempted operative repair; 85 (64 per cent) of these died within 30 days. Of the 233 patients, 92 were admitted under the care of a vascular surgeon and 141 under a non-vascular surgeon. Vascular surgeons operated on 82 patients (89 per cent), of whom 50 (61 per cent) died, whereas non-vascular surgeons operated on 51 patients (36 per cent), of whom 35 (69 per cent) died. DISCUSSION: This study is unique as it is an independent prospective study of mortality in patients with a ruptured AAA who reached hospital alive. Mortality was independent of the operating surgeon, but vascular surgeons turned down significantly fewer patients than non-vascular surgeons (11 versus 64 per cent, P < 0.001).     

Variation in death rate after abdominal aortic aneurysmectomy in the United States: impact of hospital volume, gender, and age

OBJECTIVE: To determine whether high-volume hospitals (HVHs) have lower in-hospital death rates after abdominal aortic aneurysm (AAA) repair compared with low-volume hospitals (LVHs). SUMMARY BACKGROUND DATA: Select statewide studies have shown that HVHs have superior outcomes compared with LVHs for AAA repair, but they may not be representative of the true volume-outcome relationship for the entire United States. METHODS: Patients undergoing repair of intact or ruptured AAAs in the Nationwide Inpatient Sample (NIS) for 1996 and 1997 were included (n = 13,887) for study. The NIS represents a 20% stratified random sample representative of all U.S. hospitals. Unadjusted and case mix-adjusted analyses were performed. RESULTS: The overall death rate was 3.8% for intact AAA repair and 47% for ruptured AAA repair. For repair of intact AAAs, HVHs had a lower death rate than LVHs. The death rate after repair of ruptured AAA was also slightly lower at HVHs. In a multivariate analysis adjusting for case mix, having surgery at an LVH was associated with a 56% increased risk of in-hospital death. Other independent risk factors for in-hospital death included female gender, age older than 65 years, aneurysm rupture, urgent or emergent admission, and comorbid disease. CONCLUSIONS: This study from a representative national database documents that HVHs have a significantly lower death rate than LVHs for repair of both intact and ruptured AAA. These data support the regionalization of patients to HVHs for AAA repair.     

Abdominal aortic aneurysm repair in Veterans Affairs medical centers

Purpose: This study was performed to define outcomes after abdominal ortic aneurysm (AAA) repair in Veterans Affairs (VA) medical centers during fiscal years 1991 through 1993.Methods: With VA patient treatment file data, patients were selected from diagnosis-related groups 110 and 111 and were then classified in a patient management category. In the categories of repair of nonruptured and ruptured AAA, mortality and postoperative complication rates were defined for patients who underwent AAA repair in VA medical centers during the 3-year study period.Results: Hospital mortality rates were 4.86% (166 of 3419) after repair of nonruptured AAA and 47.0% (126 of 268) after repair of ruptured AAA ( p < 0.001). Of 292 deaths after AAA repair, 126 (43.2%) followed repair of ruptured AAA, even though ruptured AAA comprised only 7.3% of total AAA surgical volume. AAA repairs were performed at 116 VA medical centers, with 31.8 ± 23.1 (range, 1 to 140) procedures performed at each center. Although many lower-volume centers had excellent results, centers that performed ≥32 AAA repairs tended to have lower in-hospital mortality rates after repair of nonruptured AAA than those that performed ≤31 procedures (4.2% ± 3.5% compared with 6.7% ± 7.8%; p < 0.05). Poisson regression analysis revealed an inverse relationship between the volume of AAA repairs and individual hospital mortality ( p = 0.001) and a direct relationship between illness severity and hospital mortality ( p = 0.008). The proportion of ruptured AAAs treated in a hospital was also directly related to individual hospital mortality rates ( p < 0.005). Postoperative complications were associated with an increased hospital mortality rate (11.7% with complication compared with 6.5% without; p < 0.001) and length of stay (23.6 ± 17.1 days compared with 18.0 ± 12.4 days; p < 0.0001). In a logistic regression model, increased mortality rates after AAA repair were associated with hospital type (adjusted odds ratio [OR] = 0.6), increasing age (OR = 1.1), patient management category severity score (OR = 2.2), hemorrhage (OR = 2.3), myocardial infarction (OR = 2.6), disseminated intravascular coagulation (OR = 4.7), AAA rupture (OR = 6.0), postoperative shock (OR = 10.7), cardiopulmonary arrest (OR = 15.4), central nervous system complications (OR = 16.0) and urologic complications (OR = 2.4).Conclusions: Mortality rates after AAA repair in VA hospitals were comparable with those previously reported in other large series. Outcomes for veterans with AAA may improve by referring patients eligible for elective repair to VA medical centers with a greater operative volume or to lower-volume centers that have had excellent results. (J VASC SURG 1996;23:191-200.)