Mass screening on abdominal aortic aneurysm in men aged 60 to 65 years in The Netherlands. Impact on life expectancy and cost-effectiveness using a Markov model.

OBJECTIVES: To predict the costs and effects on life expectancy of an AAA screening programme. METHODS: A Markov model was designed to compare the effects of a single screening for a cohort of men 60-65 years with the current no screening strategy. The following health states were distinguished: no AAA, unknown small AAA, follow-up small AAA, unknown large AAA, repaired AAA, rejected large AAA and death. Transition rates between the health states were simulated using cycle times of one year. Transition probabilities were derived from literature and a previous feasibility study. Incremental costs per life year saved were calculated. Sensitivity analyses and discounting for future effects were performed. RESULTS: The expected individual AAA costs for non-screening and AAA screening were euro; 196 and euro; 530 respectively. A difference of 3.5 months life expectancy was found in favour of screening leading to euro; 1176/life-year gained. Costs increased as compliance fell. With a discount rate of 4% the costs are euro; 2021/life-year gained. CONCLUSIONS: One-time ultrasonographic screening for AAA in men aged 60-65 years appears to be cost-effective.     

Effectiveness and cost of screening for abdominal aortic aneurysm: results of a population screening program

OBJECTIVES: We undertook this study to calculate the cost per life-year gained in the first round of a screening program for abdominal aortic aneurysm (AAA) and to estimate the costs in a subsequent round. METHODS: This was an intervention study, with follow-up for ruptured aneurysms. Men older than 50 years were screened for asymptomatic AAA. Outcome measures included cost per life-year saved and number of men needed to be screened to save one life. RESULTS: The incidence of ruptured AAA was 2.6 per 10,000 person- years in the screening group and 7.1 per 10,000 person-years in the control group. Screening is estimated to have prevented 10.8 ruptured AAA and 8 deaths per year, gaining 51 life-years per year for the study population, and to have reduced the incidence of ruptured AAA by 64% (95% CI, 42%-77%). Each life-year gained during the first screening round cost $1107. To save one life, 1000 men need to be screened and 5 elective operations performed. We predict that a second round of screening can be cost neutral. CONCLUSIONS: The cost-effectiveness of screening for AAA compares favorably with screening programs for other disorders in adults.     

Perioperative outcomes after open and endovascular repair of intact abdominal aortic aneurysms in the United States during 2001

OBJECTIVE: Small patient numbers, mixed data from clinical trials, and longitudinal series representing institutional learning curves have characterized previous studies of early outcomes after endovascular abdominal aortic aneurysm (AAA) repair. We compared the perioperative outcomes of endovascular and open surgical AAA repair in an unselected sample of patients in a single calendar year using a national administrative database. METHODS: The 2001 National Inpatient Sample database was retrospectively reviewed. This database represents 20% of all-payer stratified sample of non-federal US hospitals. Patients older than 49 years were identified by primary diagnostic codes (International Classification of Disease, ninth revision [ICD-9], 441.4, intact, nonruptured AAA) and procedure codes (ICD-9 38.44 for open, 39.71 for endovascular repair). Patient demographic data (age, sex), comorbid conditions (ICD-9 coded), inpatient complications (ICD-9 coded), length of stay, final discharge disposition (home vs institution vs death), and hospital charges were examined with univariate and multivariate analyses. RESULTS: In calendar year 2001, 7172 patients underwent either open (64%) or endovascular (36%) repair of intact, nonruptured AAAs. Despite comparable rates of preoperative comorbid conditions and a greater proportion of octogenarians (23% vs 16%%; P =.0001), morbidity (18% vs 29%; P =.0001) and mortality (1.3% vs 3.8%; P =.0001) were significantly lower for endovascular repair than for open repair. The median length of stay (2 vs 7 days; P =.0001) and the rate of discharge to an institutional facility versus home (6% vs 14%; P =.0001) were also much lower in the endovascular group than in the open repair group. At multivariate analysis, open AAA repair and age older than 80 years were strong independent predictors (P =.0001 for all) for death (open repair: odds ratio [OR], 3.3; 95% confidence interval [CI], 2.3-4.9; age: OR, 14.2; 95% CI, 3.5-58.1), complications (open repair: OR, 1.9; 95% CI, 1.7-2.1; age: OR, 1.9; 95% CI, 1.5-2.5), and not being discharged to home (open repair: OR, 3.4; 95% CI, 2.9-4.1; age: OR, 12.0; 95% CI, 7.0-20.4). Mean hospital charges were significantly greater (difference, $3337; P =.0009) for endovascular repair than for open repair. Extrapolated to the total number of endovascular AAA repairs performed during the single 2001 calendar year, this resulted in a staggering $50.3 million in additional hospital charges. CONCLUSIONS: Endovascular repair of intact AAAs results in a significantly lower number of complications and deaths, shorter hospital stay, and improved likelihood of discharge to home, even in older patients, when compared with open surgical repair. These impressive gains in clinical outcome, however, are achieved at similarly impressive increases in health care costs.     

Lifetime gain related to cost of repair of ruptured abdominal aortic aneurysm in octogenarians.

OBJECTIVE: To report cost related to gained life years after repair of ruptured abdominal aortic aneurysms in patients aged 80 or older. DESIGN: A retrospective study based on prospectively registered data. PATIENTS AND METHODS: Fifty-three patients aged 80 or older were operated on for ruptured abdominal aortic aneurysm over a 20-year period from 1983 to 2002. Thirty-one (58%) patients had systolic BT <80 mmHg. Operative mortality (<30 days) and long-term survival were studied. The number of life-years gained from the operations was estimated. Based on diagnose related group (DRG) values, the cost of each gained life-year was calculated. RESULTS: The operative mortality was 47%. Long-term survival of those patients who survived the operation was similar to that of an age and sex matched population. The 53 operations resulted in 145 gained life-years, which leaves a mean survival of 2.7 years of all the patients and 5.2 years of those who survived the operation. The estimated cost per gained life year was euro6817. CONCLUSIONS: The operative mortality of ruptured abdominal aortic aneurysm remains high. The long-term survival of patients who survive the operation is acceptable. The price of each gained life-year is low, as compared to other established treatment modalities. Improved results with endovascular treatment may even decrease the cost per gained life year.     

Cost-effectiveness of endovascular abdominal aortic aneurysm repair

BACKGROUND: The rapid introduction of endovascular abdominal aortic aneurysm repair (EVAR) has considerable implications for the management of abdominal aortic aneurysm (AAA). This study was undertaken to determine an optimal strategy for the use of EVAR based on the best currently available evidence. METHODS: Economic modelling and probabilistic sensitivity analysis considered reference cases representing a fit 70-year-old with a 5.5-cm diameter AAA (RC1) and an 80-year-old with a 6.5-cm AAA unfit for open surgery (RC2). Results were assessed as incremental cost-effectiveness ratio (ICER) compared with open repair (RC1) or conservative management (RC2). RESULTS: In RC1 EVAR produced a gain of 0.10 quality-adjusted life years (QALYs) for an estimated cost of 11,449 pound, giving an ICER of 110,000 pound per QALY. EVAR consistently had an ICER above 30,000 pound per QALY over a range of sensitivity analyses and alternative scenarios. In RC2 EVAR produced an estimated benefit of 1.64 QALYs for an incremental cost of 14,077 pound giving an incremental cost per QALY of 8579 pound. CONCLUSION:: It is unlikely that EVAR for fit patients suitable for open repair is within the commonly accepted range of cost-effectiveness for a new technology. For those unfit for conventional open repair it is likely to be a cost-effective alternative to non-operative management. Sensitivity analysis suggests that research efforts should concentrate on determining accurate rates for late complications and reintervention, particularly in patients with high operative risks.     

The Dutch Randomised Endovascular Aneurysm Management (DREAM) trial. Background,design and methods

After the introduction of endovascular repair of abdominal aortic aneurysms (AAA), both benefits and drawbacks of this new technique have been reported. To assess whether the new technique is an adequate substitute of conventional AAA repair, a randomised study is due. The Dutch Randomised Endovascular Aneurysm Management (DREAM) trial is a randomised multicenter trial enrolling patients eligible for elective treatment of infrarenal AAAs. In this study, the cost-effectiveness of endovascular aneurysm repair (EAR) is compared with that of conventional transabdominal surgery, in patients that are considered suitable for both types of treatment. The primary endpoint is combined operative mortality and morbidity. Secondary endpoints and additional assessments include event free survival, quality of life, length of hospital stay and costs. It is expected that the DREAM-trial will lead to a safe and controlled introduction of a new technology. Also, the medical community will obtain valid scientific evidence of the merits of endovascular AAA repair. Finally, policy makers will be provided with accurate cost-effectiveness data for the Dutch healthcare system. The aim of the present paper is to describe the background, methods and design of the DREAM-trial.     

The cost-effectiveness of early surgery versus watchful waiting in the management of small abdominal aortic aneurysms

Purpose: The purpose of this study was to compare the relative cost-effectiveness of two clinical strategies for managing 4 to 5 cm diameter abdominal aortic aneurysms (AAAs): early surgery (repair 4 cm AAA when diagnosed) versus watchful waiting (monitor AAA with ultrasound size measurements every 6 months and repair if the diameter reaches 5 cm).Methods: We used a Markov decision tree to compute the expected survival in quality-adjusted life years (QALYs) for each strategy, based on literature-derived estimates for the probabilities of different outcomes in this model. We determined hospital costs for patients undergoing elective and emergency AAA repair at our center. With standard methods of cost accounting, we then calculated the additional cost per year of life saved by early surgery compared with watchful waiting (cost-effectiveness ratio, dollars/QALY).Results: Mean hospital costs for elective and emergency AAA repair were $24,020 and $43,208, respectively (1992 dollars). For our base-case analysis (60-year-old men with 4 cm diameter AAAs, with 5% elective operative mortality rate and 3.3% annual rupture rate), early surgery improved survival by 0.34 QALYs compared with watchful waiting, at an incremental cost of $17,404/QALY. Increased elective surgical mortality rate, decreased AAA rupture risk, and increased patient age all reduced the cost-effectiveness of early surgery. Future increases in elective operative risk, noncompliance with ultrasound follow-up and increased threshold size for elective AAA repair during watchful waiting all improved the cost-effectiveness of early surgery. Future increases in elective operative risk, noncompliance with ultrasound follow-up and increased threshold size for elective AAA repair during watchful waiting all improved the cost-effectiveness of early surgery.Conclusions: The cost effectiveness of early surgery for 4 cm diameter AAAs in carefully selected patients compares favorably with that of other commonly accepted preventive interventions such as hypertension screening and treatment. With an upper limit of $40,000/QALY as an "acceptable" cost-effectiveness ratio, early surgery appears to be justified for patients 70 years old or younger, if the AAA rupture risk is 3%/year or more and the elective operative mortality rate is 5% or less. Although not a substitute for clinical judgment, this cost-effectiveness analysis delineates the essential tradeoffs and uncertainties in treating patients with small AAAs. (J VASC SURG 1994;19:980–91.)     

Evaluation of the effect of endovascular options on infrarenal abdominal aortic aneurysm repair

Endovascular devices designed to exclude flow to infrarenal abdominal aortic aneurysms (AAA) were approved by the Food and Drug Administration in the United States in 1999. This action allowed widespread use of this technology for AAA exclusion. The purpose of this report is to examine trends for use of these modalities, rates of rupture of AAA, and to compare results of open AAA repair with endovascular repair. Results were collected for all hospitals, except for Veterans Administration hospitals, by a state-wide repository. Data for the years 1996 through 1998 and 2001 through 2002 were evaluated, and data from 1999 through 2000 were excluded because no separate codes were available to distinguish between open and endovascular repair. The information gathered is based on the All Patient Refined Diagnostic Related Group (APRDRG; 3M, St. Paul, MN). An average of 718 open, elective AAA was performed between 1996 and 1998. This dropped to 503 open repairs from 2001 to 2002 (P < 0.005). During that same interval, 308 endovascular elective AAA repairs were performed, therefore the total rate of elective repair increased by 100. The average rate of ruptured AAA repairs from 1996 to 1998 was 121 per year, and this dropped to 89 from 2001 to 2002 (P < 0.005). The mortality of open AAA repair during the 1996 to 1998 and 2001 to 2002 intervals was unchanged (4.7%). Mortality from endovascular AAA repair between 2001 and 2002 was 1.9 per cent (P = 0.003). Major morbidity was 14.5 per cent for open, elective AAA repair and 6.3 per cent for endovascular elective repair from 2001 to 2002 (P < 0.001). These data suggest that the advent of endovascular AAA repair has contributed to a reduction in the rate of ruptured AAA repairs, an increase in total procedures performed, and a significant decrease in perioperative deaths and major complications when compared with open AAA repair.     

Durability of benefits of endovascular versus conventional abdominal aortic aneurysm repair

PURPOSE: Endovascular abdominal aortic aneurysm (AAA) repair is reported to result in less initial patient morbidity and a shorter hospital length of stay (LOS) when compared with conventional AAA repair. We sought to examine the durability of this result during the intermediate follow-up interval. METHODS: The records of all admissions for all patients who underwent AAA repair during a 26-month interval were reviewed. RESULTS: Three hundred thirty-seven (337) patients underwent procedures to repair AAAs (163 open and 174 endovascular). Endovascular procedures were performed with a variety of devices (Talent, 108; Ancure, 36; AneuRx, 26; Zenith, 2; and Cordis, 2) and configurations (141 bifurcated and 33 aortomonoiliac). The mean follow-up period was 10.6 months (endovascular repair) and 12.3 months (open repair). LOS did not significantly vary by device (P =.24 to P =.92) or configuration (P =.24). The initial median LOS for procedures was significantly shorter (P =.009) for endovascular repairs (5 days) than for open procedures (8 days). However, the patients who underwent endovascular repair were more likely to be readmitted during the follow-up interval when compared with patients who underwent open procedure. The readmission-free survival rate after AAA repair at 12 months was 95% for patients for open AAA repair versus 71% for patients for endovascular repair (P <.001). If the total hospital days were compared, including the initial and all subsequent AAA-related admissions, there was no significant difference for mean LOS for patients who underwent endovascular versus open AAA procedures (11 days versus 13.6 days; P =.21). The patients for endovascular AAA repair most commonly needed readmission for treatment of endoleak (n = 31), wound infection (n = 12), and graft limb thrombosis (n = 9). Although women had similar LOS to men for endovascular repair (P =.44), they had longer initial LOS for open AAA repair (15 versus 10 days; P =.03). After endovascular repair, women were more likely than men to be readmitted by 12 months (51% versus 71% readmission-free survival rate; P =.03) and they had longer LOS on readmission (13.2 versus 5.2 days; P =.006). No gender differences were identified for patients after open AAA repair regarding readmission-free survival rate (P =.09) or LOS on readmission (P =.98). CONCLUSION: Although initial LOS was shorter for the patients who underwent endovascular as compared with conventional AAA repair, this advantage was lost during the follow-up interval because of frequent readmission for the treatment of procedure-related complications, chiefly endoleak. These readmissions frequently involved the performance of additional invasive procedures. Gender differences existed regarding LOS and the likelihood of complications after open and endovascular AAA repair.     

Zenith AAA endovascular graft: intermediate-term results of the US multicenter trial

PURPOSE: The intent of this study was to assess the safety and effectiveness of the Zenith AAA Endovascular Graft compared with conventional aneurysm repair. MATERIAL AND METHODS: The study was conducted in a prospective, multicenter, nonrandomized, concurrent control manner. Physiologically similar patients with infrarenal abdominal aortic aneurysms (AAAs) underwent either open surgery or repair with the Zenith AAA Endovascular Graft. Separate analyses of physiologically challenged patients were performed. Follow-up was conducted at hospital discharge and at 1, 6, and 12 months (endovascular repair group) or 1 and 12 months (open surgical repair group). Evaluation included computed tomography, abdominal radiography, laboratory tests, and physical examination. Mortality (AAA-related and overall), morbidity, in-hospital recovery, renal function, and secondary interventions were assessed. Patients in the endovascular repair group were evaluated for change in aneurysm size, endoleak, graft migration, conversion, rupture, and device integrity. Statistical analyses were performed with the Kaplan-Meier method, Blackwelder test, propensity score assessment, two-sample t test, Yates-corrected Pearson chi(2) test, and Fisher exact test. RESULTS: Conventional open surgery was used in 80 patients, and 200 patients underwent repair with the Zenith AAA Endovascular Graft. Technical success was accomplished in 98.8% of patients in the open repair group and 99.5% in the endovascular repair group. Patients in the endovascular repair group had fewer significant adverse events within 30 days (80% vs 57%; P <.001). All-cause mortality was similar (endovascular, 3.5%; open surgery, 3.8%). Aneurysm-related mortality was higher with conventional surgery at 12 months (3.8% vs 0.5%; P =.04). In-hospital recovery and procedural measures were better for endovascular repair in all categories (P <.001). The incidence of endoleak was 17% at 30 days, 7.4% at 12 months, and 5.4% at 24 months. Aneurysm shrinkage (>5 mm) was noted in more than two thirds of patients at 12 months and three fourths of patients at 24 months. Renal dysfunction rate did not differ between groups. Migration (>5 mm) was detected in four (2%) patients through 12 months; none was greater than 10 mm or associated with adverse events through 24 months. Three conversions were performed within 12 months, one because of aneurysm rupture. Secondary procedures were more common in the endovascular group (11% vs 2.5%; P =.03). In total, 351 patients had endografts implanted, and 6 patients were noted to have barb separations through 12-month follow-up. No stent fractures were noted. CONCLUSIONS: The Zenith AAA Endovascular Graft is safe and effective for treatment of infrarenal AAAs. The high likelihood of decrease in aneurysm size provides evidence that treatment of aneurysms with this device reverses the natural history of aneurysmal disease. The importance of long-term follow-up is underscored by the small but defined incidence of barb separation and the potential for unforeseen failure modes.     

An analysis of standard open and endovascular surgical repair of abdominal aortic aneurysms in octogenarians

While elective open abdominal aortic aneurysm (AAA) repair has been shown to be safe in selected octogenarians, very little is known about the role of endovascular AAA exclusion in this high-risk cohort. A retrospective review of our vascular surgical registry from January 1996 to December 2001 revealed 51 octogenarians that underwent infrarenal AAA repair. Since 1999 all octogenarians who presented for AAA repair were evaluated for preferential endovascular stent graft placement. Over the 6-year period, 35 patients underwent standard open repair while 16 patients were found to be anatomic candidates for and were treated with an endovascular stent graft. Hospital and office charts were reviewed to compare the endovascular cohort to the standard open cohort. Factors considered included patient comorbidities, perioperative data, and operative outcomes. Statistical analysis was done using Wilcoxon rank sum test and Fisher exact test. The median age for the entire group was 83 years. There were 11 females in the open group and 1 female in the endovascular group. There were no statistically significant differences in preoperative patient comorbidities between groups. Total mortality for the entire series was 11.8 per cent but this included 5 ruptured AAAs, all of which patients died, and 11 additional AAAs that were symptomatic, of which 1 patient died. Total nonruptured mortality for the entire series was 2.2 per cent (0% for the endo-group and 3.3% for the open group). There were statistically significant differences between the endovascular versus the open groups when comparing aneurysm diameter (5.6 cm vs. 6.2 cm; P = 0.016), estimated blood loss (225 cc vs. 2100 cc; P < 0.001), ICU days (0 vs. 3; P < 0.001), length of hospital stay (2 days vs. 12 days; P < 0.001), and patients with blood transfusions (1 vs. 27; P < 0.001). When comparing postoperative morbidities, 4 of the endovascular patients (25%) and 25 of the open patients (68.6%) had a complication (P = 0.006). In conclusion, endovascular stent graft treatment of nonruptured infrarenal AAAs in octogenarians led to significantly better outcomes and should probably be considered the preferred treatment whenever anatomically appropriate. Endovascular exclusion of ruptured AAAs may potentially improve future outcomes in this high-risk group.     

Cost of endovascular versus open surgical repair of abdominal aortic aneurysms

BACKGROUND: Endovascular repair of abdominal aortic aneurysms (AAA) is a new minimally invasive method of aneurysm exclusion that has been adopted with increasing enthusiasm, and with acceptable clinical results. It is important, however, to assess new health-care technologies in terms of their economic as well as their clinical impact. The aim of the present study was to compare the total treatment costs for endovascular (EVR) and open surgical repair (OSR) for AAA. METHODS: A retrospective review of patient hospital and outpatient records for 62 patients undergoing either EVR (n = 31) or OSR (n = 31) was carried out between June 1996 and October 1999. Resource utilization was determined by a combination of patient clinical and financial accounting data. Costs were determined for preoperative assessment, inpatient hospital stay, cost of readmissions and follow up, and predicted lifetime follow-up costs. RESULTS: The two groups were well matched, with no significant difference with respect to age, gender, maximum aneurysm diameter or comorbid factors. Endovascular treatment resulted in a shorter intensive care unit (ICU) and hospital stay (mean: 0.07 vs 2.9 days, P < 0.001; mean: 6.0 vs 13.4 days, P < 0.001; respectively) and fewer postoperative complications (P = 0.003). The cost of hospitalization was less for EVR ($7614 vs $15092, P < 0.001), but this was offset by the more costly vascular prosthesis ($10284 vs $686). Costs were higher for the EVR group for preoperative assessment ($2328 vs $1540, P < 0.001) and follow up ($1284 vs $70, P < 0.001). Lifelong follow up could be expected to cost an additional $4120 per patient after EVR. Total lifetime treatment costs including costs associated with readmission for procedure-related complications were higher for EVR ($26909 vs $17650). CONCLUSION: Treatment costs for endovascular repair are higher than conventional surgical repair due to the cost of the vascular prosthesis and the greater requirement for radiological imaging studies.     

Cost-effectiveness of fracture prevention in established osteoporosis

This study presents the results of a computer simulation model for calculating the cost-effectiveness and cost-utility of treating patients with established osteoporosis in order to reduce the risk of fractures. The results are based on Swedish data for risk of fracture and costs. The treatment intervention modelled is based on treatment of a 62-year-old woman with established osteoporosis. The cost per hip fracture avoided is 350000 SEK, assuming a 50% reduction in the risk of fracture due to 5 years of treatment. A sensitivity analysis for changes in the cost and effectiveness of treatment, the risk of fracture and the discount rate is performed. The cost per life-year gained and the cost per quality-adjusted life-year (QALY) gained is presented to enable comparison of the cost-effectiveness of treating osteoporosis with that of other health care interventions. A comparison between treating the same woman for osteoporosis and mild hypertension shows a cost per life-year gained of 220000 SEK and 128000 SEK respectively. Cost per QALY gained is very similar for the two interventions: 105 000 SEK and 103 000 SEK respectively. This model provides a tool to enable clinicians, administrators and health policy makers to analyze and understand the economic aspects of a major health policy issue.     

Mortality,Morbidity, and Costs of Ruptured and Elective Abdominal Aortic Aneurysm Repairs in Nova Scotia,Canada

Ruptured abdominal aortic aneurysms (RAAA) have a 78-94% mortality rate. If cost-effectiveness of screening programs for abdominal aortic aneurysms (AAA) are to be assessed, direct costs for RAAA repairs and elective AAA (EAAA) repairs are required. This study reports mortality, morbidity, and direct costs for RAAA and EAAA repairs in Nova Scotia in 1997-1998 and also compares Nova Scotia and U.S. costs. We performed a retrospective study of 41 consecutive RAAA and 48 randomly selected EAAA patients. Average total costs for RAAA repair were significantly greater than those for EAAA repair (direct costs: $15,854 vs. $9673; direct plus overhead costs: $18,899 vs. $12,324 [pricing in 1998 Canadian dollars]). Intensive care unit length of stay and blood product usage were the most substantial direct cost differentials ($3593 and $2106). Direct cost for preoperative testing and surveillance was greater in the EAAA group ($839 vs. $33). Estimates of U.S. in-hospital RAAA and EAAA repair costs are more than 1.5 times Nova Scotia costs. Direct in-hospital RAAA repair costs are $6181 more than EAAA repair costs. These in-hospital cost data are key cost elements required to assess the cost-effectiveness of various screening strategies for earlier detection and monitoring of AAA within high-risk populations in Canada. Further studies are required to estimate cost per quality-adjusted-life-year gained for various AAA screening and monitoring strategies in Canada.     

A prospective study of subclinical myocardial damage in endovascular versus open repair of infrarenal abdominal aortic aneurysms

BACKGROUND: Endovascular repair of abdominal aortic aneurysms (AAAs) is considered to be less invasive and better tolerated by the cardiovascular system than open repair. Our aim was to assess the true incidence of perioperative myocardial damage associated with endovascular vs open infrarenal AAA repair. METHODS: Between July 1999 and June 2001, preoperative and postoperative serum troponin T (TnT) levels were measured in all patients presenting for elective AAA repair at Royal Prince Alfred Hospital. The incidence of myocardial damage was recorded on the basis of standard clinical, biochemical, and electrocardiographic changes or a subclinical increase of 50% or more in serum TnT. Patients were excluded if the TnT increase was associated with a significant increase of serum creatinine (> or =50%) with no other evidence of myocardial ischemia. The differences between the two groups were analyzed with the chi 2 test and odds ratios. RESULTS: A total of 35 open and 112 endovascular AAA repairs were included in the study. There was no significant difference in age, sex, preoperative serum creatinine, or preoperative serum TnT between the two treatment groups. Seventeen patients had biochemical evidence of myocardial damage, which was clinically obvious in only one patient. Even though the incidence of previous myocardial infarction was significantly higher in patients undergoing endovascular repair (41%) than open repair (22%; P < .05), the overall incidence of myocardial damage (clinical or subclinical) was significantly higher in the open group compared with the endovascular group (8 [25%] of 32 vs 9 [8%] of 109, respectively; odds ratio, 3.7; 95% confidence interval, 1.28-10.49; P < .02). CONCLUSIONS: There is a previously underestimated incidence of subclinical myocardial damage associated with surgery for infrarenal AAA which is lower after endovascular than open repair.     

Quality of life before and after endovascular and retroperitoneal abdominal aortic aneurysm repair

PURPOSE: This study was undertaken to evaluate changes in quality of life and to compare conventional outcomes in patients undergoing endovascular and open retroperitoneal abdominal aortic aneurysm (AAA) repair. METHODS: Between October 2000 and May 2003, 129 patients underwent elective AAA repair, endovascular repair in 22 patients and open retroperitoneal repair in 107 patients. The Short-Form Health Survey, 12 items (SF-12) was administered preoperatively and at 3 weeks, 4 months, and 1 year after discharge. Quality of life, hospital and intensive care unit stay, perioperative complications, discharge disposition, readmission, and hospital cost were statistically evaluated. RESULTS: For the total group, significant differences were observed for both Physical Component Summary scores (P<.001) and Mental Component Summary scores (P=.001) between time points. There were no significant differences for either Component Summary score between open and endovascular procedures for any time period. Number of weeks required to return to baseline functional status was similar after either open or endovascular repair (7.22 vs 5.47 weeks, respectively; P=.09). Mean hospital and intensive care unit stay was 4.4 and 1 days, respectively, for open repair versus 1.9 and 0 days, respectively, for endovascular repair (P<.0001). No significant difference between groups was observed in terms of perioperative complications, discharge disposition, or hospital readmission (P> or =.54). Mean total hospital cost for endovascular repair was 1.60 times that for open repair (mean difference, $11,662; P<.0001; 95% confidence interval, $17,799-$5525). CONCLUSIONS: Hospital stay is significantly shorter after endovascular AAA repair. However, hospital cost is almost twice that for open retroperitoneal repair. Perioperative complications, discharge disposition, and hospital readmission are not statistically different between the two groups. Effect on health-related quality of life is similar after either open retroperitoneal or endovascular AAA repair.     

Cost-Effectiveness of Preventing Hip Fracture in the General Female Population

The aims of this study were to determine whether treatments that reduce the incidence of hip fracture might be used in the general female population rather than screening or case-finding strategies. Cost-effectiveness, measured as cost per quality-adjusted life-year (QALY) gained using threshold values for cost-effectiveness of $20.000 or $30.000/QALY gained, was assessed during and after treatment using a computer simulation model applied to the female population of Sweden. The base case assumed a 5-year intervention that reduced the risk of hip fracture by 35% during the treatment period, and an effect that reversed to the pretreatment risk during the next 5 years. Sensitivity analyses included the effects of age, different treatment costs and effectiveness. Cost-effectiveness was critically dependent upon the age and costs of intervention. Reasonable cost-effectiveness was shown even with relatively high intervention costs for women at average risk at the age of 84 years or more. For the cheapest interventions ($63/year) cost-effectiveness could be found from the age of 53 years. Variations in effectiveness (15–50% risk reduction) had marked effects on the age that treatment was worthwhile. We conclude that segments of the apparently healthy population could be advantaged by treatment if efficacy were supported by randomized controlled studies. Received: May 2000 / Accepted: November 2000     

Decision-analytical model with lifetime estimation of costs and health outcomes for one-time screening for abdominal aortic aneurysm in 65-year-old men

BACKGROUND: Abdominal aortic aneurysm (AAA) causes about 2 per cent of all deaths in men over the age of 65 years. A major improvement in operative mortality would have little impact on total mortality, so screening for AAA has been recommended as a solution. The cost-effectiveness of a programme that invited 65-year-old men for ultrasonographic screening was compared with current clinical practice in a decision-analytical model. METHODS: In a probabilistic Markov model, costs and health outcomes of a screening programme and current clinical practice were simulated over a lifetime perspective. To populate the model with the best available evidence, data from published papers, vascular databases and primary research were used. RESULTS: The results of the base-case analysis showed that the incremental cost per gained life-year for a screening programme compared with current practice was 7760, and that for a quality-adjusted life-year was 9700. The probability of screening being cost-effective was high. CONCLUSION: A financially and practically feasible screening programme for AAA, in which men are invited for ultrasonography in the year in which they turn 65, appears to yield positive health outcomes at a reasonable cost.     

An economic evaluation of lung transplantation

OBJECTIVE: This study was undertaken to determine the cost per quality-adjusted life-year gained with lung transplantation relative to medical treatment for end-stage lung disease in the United Kingdom. METHODS: Patients on the transplant waiting list were used to represent medical treatment. Four-year national survival data were extrapolated to 15 years by means of parametric techniques. Quality-adjusted life-years were derived by means of utility scores obtained from a cross-section of patients. Resource consumption and costs were based on local and national sources. Costs and benefits were discounted at an annual rate of 6%. RESULTS: Across a 15-year period lung transplantation yielded mean benefits (relative to medical treatment) of 2.1, 3.3, and 3.6 quality-adjusted life-years for single-lung, double-lung, and heart-lung transplantation, respectively. During the same period the mean cost of medical treatment was estimated at $73,564, compared with $176,640, $180,528, and $178,387 for single-lung, double-lung, and heart-lung transplantation, respectively. The costs per quality-adjusted life-year gained were $48,241 for single-lung, $32,803 for double-lung, and $29,285 for heart-lung transplantation. Sensitivity analysis found the principal determinants of cost-effectiveness to be quality of life and maintenance costs after transplantation. CONCLUSIONS: Lung transplantation results in survival and quality of life gains but remains expensive, with cost-effectiveness limited by substantial mortality and morbidity and high costs. The cost-effectiveness of lung transplantation can be improved with lowered immunosuppression costs and improvements in quality of life after transplantation.     

Analysis of renal function after aneurysm repair with a device using suprarenal fixation (Zenith AAA Endovascular Graft) in contrast to open surgical repair

PURPOSE: This study was undertaken to assess the effect on renal function of open surgery and endovascular abdominal aortic aneurysm (AAA) repair with suprarenal fixation with the Zenith device. METHODS: Data for 279 patients with similar preoperative comorbid conditions were prospectively analyzed after AAA repair. One hundred ninety-nine patients underwent endografting with the Zenith AAA Endovascular Graft, which incorporates suprarenal fixation (Zenith standard risk group, ZSR), and 80 patients underwent open surgery (standard surgical risk group, SSR). Endovascular repair was also performed in 100 patients considered poor candidates for open repair (Zenith high risk group, ZHR). Serum creatinine concentration (SCr) and anatomic defects were assessed before the procedure, before discharge, and at 1, 6, 12, and 24 months in all patients who underwent endovascular repair, and before the procedure and at 1 and 12 months in patients who underwent open surgical repair (only SCr was measured before discharge). Renal function was also analyzed, with a creatinine clearance calculation (Cockcraft-Gault). Renal insufficiency was defined as an increase in SCr greater than 30% from a preoperative baseline value, any SCr concentration in excess of 2.0 mg/dL, or any need for dialysis. Cumulative renal infarction and arterial occlusion rates were calculated with computed tomographic, ultrasonographic, and angiographic data, and reported as cumulative values. RESULTS: Despite the initially superior renal function in the ZSR group at the pre-discharge evaluation (P =.01), there were no differences at 12 months with respect to rise in SCr greater than 30% (ZSR, 16%, vs SSR, 12%; P =.67), SCr rise greater than 2.0 mg/dL (ZSR, 2.5%, vs SSR, 3.4%; P =.66), incidence of renal artery occlusion (ZSR, 1%, vs SSR, 1.4%; P >.99), or infarction (ZSR, 1.5%, vs SSR, 1.4%; P >.99). Only one patient in each group required hemodialysis. Of note, both groups of patients demonstrated a reduction in creatinine clearance over 12 months, which then stabilized or improved by 24 months for ZSR patients. CONCLUSIONS: Renal dysfunction occurs in a subset of patients regardless of type of repair (open or endovascular with suprarenal fixation). The cause of renal dysfunction after open or endovascular repair with a suprarenal stent is probably multifactorial. The observed dysfunction occurs in a small number of patients, and the effect in the endovascular group (no data for the surgical group at 24 months) appears to be transient. The initial dysfunction, apparent in both groups over 12 months of follow-up, stabilizes or improves at 12 to 24 months.