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.)     

The cost-effectiveness of repairing ruptured abdominal aortic aneurysms

BACKGROUND: Although advances in technology have reduced the operative risk of elective abdominal aortic aneurysm (AAA) repair, the surgical repair of ruptured AAAs is associated with a much poorer prognosis and a higher cost. Accordingly, it has been suggested that patients with predictably high rates of morbidity and mortality from ruptured AAA may not benefit from surgical intervention.Methods and Results: A cost-effectiveness analysis was performed with the use of a Markov decision-analytic model to compute long-term survival in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients with ruptured AAAs managed with either a strategy of open surgical repair or no intervention. Probability estimates for the various outcomes were based on a review of the literature. Average costs of (1) the immediate hospitalization ($28,356) and (2) complications resulting from the procedure were based on the average use of resources as reported in the literature and from a hospital's cost accounting system. Our measure of outcome was the incremental cost-effectiveness ratio. For our base-case analysis, the repair of ruptured AAAs was cost-effective with an incremental cost-effectiveness ratio of $10,754. (Society is usually willing to pay for interventions with cost-effectiveness ratios of less than $60,000; for example, the costeffectiveness ratios for coronary artery bypass grafting and dialysis are $9500 and $54,400, respectively.) In sensitivity analyses, the cost-effectiveness of repairing ruptured AAAs was influenced only by alterations in the operative mortality. If the operative mortality exceeded 88%, repair of ruptured AAAs was no longer cost-effective. As an independent variable, increasing age had no substantial impact on the cost-effectiveness, although it is reported to be associated with increased operative mortality. It was necessary that the patient's cost of the initial hospitalization for ruptured AAA exceed $195,000 before repairing ruptured AAAs was no longer cost-effective. CONCLUSIONS: Our analysis suggests that despite the high cost and poor outcomes, the surgical repair of ruptured AAAs is still cost-effective when compared with no intervention. The cost of repairing ruptured AAAs falls within society's acceptable limits and therefore should not be a consideration in the management of patients with AAAs.     

Cost-effectiveness of different screening strategies for abdominal aortic aneurysm

OBJECTIVE: The primary objective of this study was to develop a simulation model to assess the cost-effectiveness of different screening strategies for abdominal aortic aneurysms (AAAs) in men. METHODS: A systematic review of the literature was conducted for different screening strategies in terms of age (60, 65, or 70 years) and risk profiles (all men or specific high-risk groups) of the screened population, and rescreening after 5 or 10 years. These data were analyzed in a Markov simulation cohort model. RESULTS: The cost per life year gained for different screening strategies ranged from US 8,309 dollars to US 14,084 dollars and was estimated at US 10,474 dollars when 65-year-old men were screened once. Screening 60-year-old men was equally cost-effective, with the advantage of more life years gained. We demonstrated a trade-off between high prevalence of AAA and lower life expectancy, eliminating the expected benefits of screening high-risk groups such as smokers (US 10,695 dollars) or cardiovascular patients (US 10,392 dollars). Assuming general population utility resulted in a cost per quality-adjusted life year (QALY) gained of US 13,900 dollars, whereas a hypothetical 5% reduction in utility among men with a screening-detected AAA raised the cost per QALY gained to US 75,100 dollars. CONCLUSION: This Markov model, which was based on a systematic review of the literature, supplied information on the estimated cost-effectiveness of different screening strategies. Screening men for AAA may be cost-effective in the long-term. Different screening strategies and quality-of-life effects related to screening for AAA need to be evaluated in future clinical studies.     

Cost-effectiveness analysis of laparoscopic gastric bypass, adjustable gastric banding, and nonoperative weight loss interventions

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) and laparoscopic Roux-en-Y gastric bypass (LRYGB) are the two most commonly performed bariatric procedures. Although both procedures likely reduce healthcare expenditures related to the resolution of co-morbid conditions, they have different rates of perioperative risks and different rates of associated weight loss. We designed a model to evaluate the incremental cost-effectiveness of these procedures compared with nonoperative weight loss interventions and with each other. METHODS: We used a deterministic, payer-perspective model comparing the lifetime expected costs and outcomes of LAGB, LRYGB, and nonoperative treatment. The major endpoints were survival, health-related quality of life, and weight loss. Life expectancy and lifetime medical costs were calculated across age, gender, and body mass index (BMI) strata using previously published data. RESULTS: For both men and women, LRYGB and LAGB were cost-effective at <$25,000/quality-adjusted life-year (QALY) even when evaluating the full range of baseline BMI and estimates of adverse outcomes, weight loss, and costs. For base-case scenarios in men (age 35 y, BMI 40 kg/m(2)), the incremental cost-effectiveness was $11,604/QALY for LAGB compared with $18,543/QALY for LRYGB. For base-case scenarios in women (age 35 y, BMI 40 kg/m(2)), the incremental cost-effectiveness was $8878/QALY for LAGB compared with $14,680/QALY for LRYGB. CONCLUSION: The modeled cost-effectiveness analysis showed that both operative interventions for morbid obesity, LAGB and RYGB, were cost-effective at <$25,000 and that LAGB was more cost-effective than RYGB for all base-case scenarios.     

The cost-effectiveness of endovascular repair versus open surgical repair of abdominal aortic aneurysms: A decision analysis model

PURPOSE: Endovascular repair (EVR) is a less-invasive method for the treatment of abdominal aortic aneurysms (AAAs) as compared with open surgical repair (OSR). The potential benefits of EVR include increased patient acceptance, less resource utilization, and cost savings. This study was designed to determine whether the EVR of AAAs is a cost-effective alternative to OSR. METHODS: A cost-effectiveness analysis was performed using a Markov decision analysis model to compute long-term survival rates in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients who underwent either OSR or EVR. Probability estimates of the different outcomes of the two alternative strategies were made on the basis of a review of the literature. The average costs of (1) the immediate hospitalization ($16,016 for OSR, $20,083 for EVR), (2) the complications that resulted from each procedure, (3) the subsequent interventions, and (4) the surveillance protocol were determined on the basis of average resource utilization as reported in the literature and from our hospital's cost accounting system. Our measure of outcome was the cost-effectiveness ratio. RESULTS: For our base-case analysis (70-year-old men with 5-cm AAAs), EVR was cost-effective with a cost-effectiveness ratio of $22,826-society usually is willing to pay for interventions with cost-effectiveness ratios of less than $60,000 (eg, cost-effectiveness ratios for coronary artery bypass grafting and dialysis are $9500 and $54,400, respectively). This conclusion did not vary significantly with increases in procedural costs for EVR (ie, if the cost of the endograft increased from $8000 to $12,000, EVR remained cost-effective with a cost-effectiveness ratio of $32,881). The cost-effectiveness of EVR was critically dependent on EVR producing a large reduction in the combined mortality and long-term morbidity rate (stroke, dialysis-dependent renal failure, major amputation, myocardial infarction) as compared with OSR (ie, a reduction in the combined mortality and long-term morbidity rate of OSR from 9.1% to 4.7% made EVR no longer cost-effective). CONCLUSION: Despite the high cost of new technology and the need for close postoperative surveillance, EVR is a cost-effective alternative for the repair of AAAs. However, the cost-effectiveness of this new technology is critically dependent on its potential to reduce morbidity and mortality rates as compared with OSR. EVR may not be cost-effective in medical centers where OSR can be performed with low risk.     

Cost-effectiveness of screening women for abdominal aortic aneurysm

BACKGROUND: Women are usually not considered for abdominal aortic aneurysm (AAA) screening because of their lower prevalence of disease. This position may, however, be questioned given the higher risk of rupture and the longer life expectancy among women. The purpose of this study was to assess the cost-effectiveness of screening 65-year-old women for AAA. METHODS: A systematic review of the literature was conducted to obtain data of importance to evaluate the effectiveness of screening women for AAA. Data were entered into a Markov simulation cohort model. RESULTS: The review suggested some main assumptions for women with AAA. Prevalence is 1.1%. In 6.8%, the AAA is of a size that merits surgery, and the patients are fit for a procedure. For patients with an AAA, the yearly risk for elective surgery and the rupture incidence was 3.1% and 2.4%, respectively, in the invited group and 1.1% and 5.7% in the noninvited group. The operative mortality for elective surgery was 3.5%, and the total mortality for ruptured AAA was 86.3%. The long-term mortality for AAA patients was 3.6 times higher than for an age-matched healthy population. Screening reduced the AAA rupture incidence by 33% and the AAA-related death rate by 35%. The cost per life year gained was estimated at $5911. CONCLUSION: The incremental cost-effectiveness ratio was similar to that found for screening men, which reflects the fact that the lower AAA prevalence in women is balanced by a higher rupture rate. Screening women for AAA may be cost-effective, and future evaluations on screening for AAA should include women.     

Operative treatment of abdominal aortic aneurysms in octogenarians. When is it too much too late?

OBJECTIVE: This study evaluated the value of operation for treatment of all octogenarians with ruptured abdominal aortic aneurysms (AAA). SUMMARY BACKGROUND DATA: Elective AAA resection in octogenarians is safe, with published operative mortality rates of approximately 5%. Published operative mortality rates of ruptured AAA in this age group, however, vary from 27 to 92%. METHODS: To evaluate this question, we extracted the clinical course of the 34 octogenarians submitted to AAA resection by the authors from our total experience of 548 resections performed during the past 7 1/2 years. In this subgroup of octogenarians, 18 underwent elective AAA replacement, 5 were submitted to urgent resection of active but intact AAAs, and 11 had operations for ruptured AAAs. There were 23 males and 11 females in the group. The ages ranged from 80 to 91 years. RESULTS: Operative mortality in the patients managed electively was 5.6%. Two of the five patients (40%) submitted to operation for active yet unruptured aneurysms died in the preoperative period. Finally, 10 of the 11 patients (91%) with ruptured AAAs were operative mortalities. All of these operative mortalities in the ruptured AAA subgroup had severe hypotension preoperatively (mean systolic blood pressure: 23 mm Hg). The charges associated with the management of the ruptured AAA group averaged $84,486 (range $12,537-$199,233). CONCLUSIONS: Although elective replacement of AAA in properly selected octogenarians appears valuable to prolong worthwhile life expectancy, this experience leads us to consider observation only in the treatment of octogenarians with ruptured AAA who present with severe hemodynamic instability.     

Cost-utility analysis of emergency department thoracotomy for trauma victims

BACKGROUND: Our objective was to assess the cost-effectiveness of emergency department thoracotomy (EDT) performed on both penetrating and blunt trauma victims, using both published survival and outcome data and previously unaccounted for data on the cost of occupational exposure. METHODS: Cost-utility analysis was performed using decision-analytic models constructed for both penetrating and blunt trauma scenarios. Survival and impairment data, the rates and costs of occupational exposure, and the utilities of neurologic impairment and provider seroconversion were all based on published literature. Costs of EDT were estimated using the National Inpatient Sample (NIS) from the Health Care Utilization Project database. One-way sensitivity analyses on input parameters and probabilistic sensitivity analyses using Monte Carlo simulations were performed. RESULTS: The incremental cost-effectiveness ratio of EDT for penetrating trauma was $16,125 per quality-adjusted life year (QALY), and less than $50,000 per QALY with a 93.4% probability. The incremental cost-effectiveness ratio for blunt trauma was $163,136 per QALY, and less than $50,000 per QALY with a 37% probability. Neither model was sensitive to provider exposure. The penetrating model was insensitive to the probability of neurologically intact survival, the utility adjustment, procedure costs, and long-term care. The blunt model was sensitive to the probabilities of survival and of neurologic impairment. CONCLUSIONS: EDT is cost-effective for penetrating trauma, and not cost-effective for blunt trauma given current rates of survival and impairment. Occupational exposure does not significantly impact the cost-effectiveness of the procedure.     

Cost-effectiveness of conventional and endovascular repair of abdominal aortic aneurysms: results of a randomized trial

BACKGROUND: Two randomized trials have shown similar mid-term outcomes for survival and quality of life after endovascular and conventional open repair of abdominal aortic aneurysms (AAA). With reduced hospital and intensive care stay, endovascular repair has been hypothesized to be more efficient than open repair. The Dutch Randomized Endovascular Aneurysm Management (DREAM) trial was undertaken to assess the balance of costs and effects of endovascular vs open aneurysm repair. METHODS: We conducted a multicenter, randomized trial comparing endovascular repair with open repair in 351 patients with an AAA and studied costs, cost-effectiveness, and clinical outcome 1 year after surgery. In addition to clinical outcome, costs and quality of life were recorded up to 1 year in 170 patients in the endovascular repair group and in 170 in the open repair group. Incremental cost-effectiveness ratios were estimated for cost per life-year, event-free life-year, and quality adjusted life-year (QALY) gained. Uncertainty regarding these outcomes was assessed using bootstrapping. RESULTS: Patients in the endovascular repair group experienced 0.72 QALY vs 0.73 in the open repair group (absolute difference, 0.01; 95% confidence interval [CI], -0.038 to 0.058). Endovascular repair was associated with additional euro 4293 direct costs (euro 18,179 vs euro 13.886; 95% CI, euro 2,770 to euro 5,830). Most of the bootstrap estimates indicated that endovascular repair resulted in slightly longer overall and event-free survival associated with respective incremental cost-effectiveness ratios of euro76,100 and euro 171,500 per year gained. Open repair appeared the dominant strategy in costs per QALY. CONCLUSION: Presently, routine use of endovascular repair in patients also eligible for open repair does not result in a QALY gain at 1 year postoperatively, provides only a marginal overall survival benefit, and is associated with a substantial, if not prohibitive, increase in costs.     

Kidney transplantation in the elderly: a decision analysis

Transplantation offers superior life expectancy and quality of life compared with dialysis in young patients with end-stage renal failure. However, the initial risks of mortality and morbidity are high. This study used a decision analysis model to evaluate the costs and benefits of kidney transplantation versus continued dialysis for older patients with renal failure. A decision analytic model comparing cadaveric renal transplantation to continued hemodialysis treatment was developed. The base case considered a theoretical cohort of patients aged 65 yr without known comorbidity or contraindications to transplantation who would have to wait 2 yr for a cadaveric transplant. Separate models were constructed for patients with diabetes or cardiovascular disease and for patients receiving an organ after a variety of wait-list times. Probability, utility, and survival data were obtained from published reports and renal registries. For 65-yr-old patients, quality-adjusted life expectancy increased by 1.1 quality-adjusted life years (QALY) at an incremental cost of $67,778 per QALY. Assuming a 2-yr wait-listed time, transplantation remained economically attractive for 70-yr-old patients (incremental cost effectiveness [ICE], $79,359 per QALY) but was less economically attractive for those over 75 yr of age (ICE, $99,553) or for 70-yr-olds with either cardiovascular disease or diabetes (ICE, $126,751 and $161,090 per QALY, respectively). The analytic results were sensitive only to the time spent waiting for the graft. The cost-effectiveness reduced such that the costs associated with one QALY were in excess of $100,000/yr when the probability of a complication was > or = 50% per 3-mo cycle and when the utility of transplantation fell below 0.62. If available within a timely period, transplantation may offer substantial clinical benefits to older patients at a reasonable financial cost. Prolonged waiting times dramatically decrease the clinical benefits and economic attractiveness of transplantation, suggesting that living donor transplantation may be of particular benefit in this population.     

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.     

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.     

CAGS AND ACS EVIDENCE BASED REVIEWS IN SURGERY. 45: Cost-effectiveness of bariatric surgery for severely obese adults with diabetes

Objective: To analyze the cost-effectiveness of bariatric surgery in severely obese adults who have diabetes. Base case: Patients with body mass index (BMI) ≥ 35 who have diabetes. Methods: The Centre for Disease Control (CDC)-RTI Diabetes Cost-Effectiveness Model, which is a Markov simulation model of disease progression and cost-effectiveness for type 2 diabetes, was expanded to consider the effects of bariatric surgery. Interventions considered: Gastric bypass and gastric banding compared with usual diabetes care. Outcomes considered: Diabetes-related and surgical complications, diabetes remission and relapse rates, deaths, costs and quality of life. Results: Bariatric surgery increased quality-adjusted life years (QALYs) and increased costs. Bypass surgery had cost-effectiveness ratios of $7 000 per QALY and $12 000 per QALY for severely obese patients with newly diagnosed and established diabetes, respectively. Gastric banding had cost-effectiveness ratios of $11 000 per QALY and $13 000 per QALY, respectively. In sensitivity analyses, the cost-effectiveness ratios were most affected by assumptions about the direct gain in quality of life and by BMI reduction following surgery. Conclusion: The analysis indicates that gastric bypass and gastric banding are cost-effective methods of reducing mortality and diabetes-related complications in severely obese adults with diabetes.     

Tension-free repair versus watchful waiting for men with asymptomatic or minimally symptomatic inguinal hernias: a cost-effectiveness analysis

BACKGROUND: Watchful waiting (WW) has been shown to be an acceptable option in men with asymptomatic or minimally symptomatic inguinal hernias when clinical and patient-reported outcomes are considered. Although WW is likely to be less costly initially when compared with tension-free repair (TFR) because of the cost of the operation, it is not clear whether WW remains the least costly option when longer-term costs are considered. STUDY DESIGN: We conducted a cost-effectiveness analysis of a randomized controlled trial at six community and academic centers. We examined costs, quality-adjusted life-years (QALY), and cost-effectiveness at 2 years of followup. Costs were assessed by applying Medicare reimbursement rates to patients' health-care use, which was obtained by contacting patients' health-care providers. Quality of life was assessed using the Short Form-36 version 2 health-related quality-of-life survey. Of the 724 men randomized, 641 were available for the economic analysis: 317 were randomized to TFR and 324 were randomized to watchful waiting. RESULTS: At 2 years, TFR patients had $1,831 higher mean costs than WW patients (95% CI, $409-$3,044), with 0.031 higher QALY (95% CI, 0.001-0.058). The cost per additional QALY for TFR patients was $59,065 (95% CI, $1,358-$322,765). The probability that TFR was cost-effective at the $50,000 per QALY level was 40%. CONCLUSION: At 2 years, WW was a cost-effective treatment option for men with minimal or no hernia symptoms.     

Cost-effectiveness of surgical treatment of adult spinal deformity: comparison of posterior-only versus anteroposterior approach

BACKGROUND CONTEXTConsiderable debate exists regarding the optimal surgical approach for adult spinal deformity (ASD). It remains unclear which approach, posterior-only or combined anterior-posterior (AP), is more cost-effective. Our goal is to determine the 2-year cost per quality-adjusted life year (QALY) for each approach.PURPOSETo compare the 2-year cost-effectiveness of surgical treatment for ASD between the posterior-only approach and combined AP approach.STUDY DESIGNRetrospective economic analysis of a prospective, multicenter databasePATIENT SAMPLEFrom a prospective, multicenter surgical database of ASD, patients undergoing five or more level fusions through a posterior-only or AP approach were identified and compared.METHODSQALYs gained were determined using baseline, 1-year, and 2-year postoperative Short Form 6D. Cost was calculated from actual, direct hospital costs including any subsequent readmission or revision. Cost-effectiveness was determined using cost/QALY gained.RESULTSThe AP approach showed significantly higher index cost than the posterior-only approach ($84,329 vs. $64,281). This margin decreased at 2-year follow-up with total costs of $89,824 and $73,904, respectively. QALYs gained at 2 years were similar with 0.21 and 0.17 in the posterior-only and the AP approaches, respectively. The cost/QALY at 2 years after surgery was significantly higher in the AP approach ($525,080) than in the posterior-only approach ($351,086).CONCLUSIONSWe assessed 2-year cost-effectiveness for the surgical treatment through posterior-only and AP approaches. The posterior-only approach is less expensive both for the index surgery and at 2-year follow-up. The QALY gained at 2-years was similar between the two approaches. Thus, posterior-only approach was more cost-effective than the AP approach under our study parameters. However, both approaches were not cost-effective at 2-year follow-up.     

The cost-effectiveness of a "quick-screen" program for abdominal aortic aneurysms

BACKGROUND: The incidence of abdominal aortic aneurysm (AAA) is increasing, and the prognosis of ruptured AAA remains dismal. Early diagnosis and intervention are crucial. We designed this study to determine whether selected population screening with a brief "quick-screen" ultrasound could be cost-effective. METHODS: A series of 25 patients with risk factors for AAA were evaluated in a blinded fashion by a quick-screen ultrasound and a full conventional study. Times and accuracy for the 2 approaches were compared. An analysis of the cost-effectiveness of screening for AAA was then performed using a Markov model. We determined the long-term survival in quality-adjusted life years and lifetime costs for a hypothetical cohort of 70-year-old males undergoing either AAA screening or not. Our measure of outcome was the cost-effectiveness ratio (CER). RESULTS: The average time for a quick screen was one-sixth that of a conventional study (4 vs 24 minutes). The accuracy of the quick screen was 100%. In our base-case analysis, screening for AAA was cost-effective with a CER of $11,215. Society usually is willing to pay for interventions with CER of less than $60,000 (eg, CER for coronary artery bypass grafting, $9500; breast cancer screening, $16,000). In sensitivity analysis, reducing the cost of screening from $259 (approximate Medicare reimbursement) to $40 (the quick screen) improved the CER to $6850. Moreover, screening populations with increased prevalence of AAA (eg, male with family history [18%]) further improved the CER. CONCLUSIONS: Our analysis demonstrates that ultrasound screening for AAA should be offered to all males above the age of 60. Widespread screening for AAA should be adopted and reimbursed by Medicare and other insurers.     

Cost-effectiveness of hepatic metastasectomy in patients with metastatic colorectal carcinoma: a state-transition Monte Carlo decision analysis

OBJECTIVE: To evaluate the cost-effectiveness of hepatic resection ("metastasectomy") in patients with metachronous liver metastases from colorectal carcinoma (CRC), and to investigate the impact of operative and follow-up strategies on outcomes, cost, and cost-effectiveness. SUMMARY BACKGROUND DATA: There is substantial evidence that resection of CRC liver metastases can result in long-term survival in some patients. However, several unresolved issues are difficult to address using currently available clinical data. These include the appropriate threshold for resection, whether to perform repeat resection, and the relative cost-effectiveness of the procedure(s). METHODS: The authors developed a state-transition Monte Carlo decision model to evaluate the (societal) cost-effectiveness of hepatic metastasectomy in patients with metachronous CRC liver metastases. The model tracks the presence, number, size, location, growth, detection, and removal of up to 15 individual metastases in each patient. Survival, quality of life, and cost are predicted on the basis of disease extent. Imaging and surgery affect outcomes via detection and removal of individual metastases. Several patient management strategies were developed and compared with respect to cost, effectiveness, and incremental cost-effectiveness ($/quality-adjusted life year [QALY]). A reference strategy in which metastasectomy is not offered and imaging is not performed for the purpose of assessing resectability or operative planning ("no-surgery" strategy) was included for comparison. Extensive sensitivity analysis was performed to evaluate the impact of alternative model assumptions on results. RESULTS: A strategy permitting resection of up to six metastases and one repeat resection, with CT follow-up every 6 months, resulted in a gain of 2.63 QALYs relative to the no-test/no-treat strategy, at an incremental cost of 18,100 US dollars/QALY. When additional surgical strategies were considered, the incremental cost-effectiveness ratio (ICER; relative to the next least effective strategy) of the six metastases, one repeat, 6-month strategy was 31,700 US dollars/QALY. Across a range of model assumptions, more aggressive treatment strategies (i.e., resection of more metastases, resection of recurrent metastases) were superior to less aggressive strategies and had ICERs below 35,000 US dollars/QALY. Findings were insensitive to changes in most model parameters but somewhat sensitive to changes in surgery and treatment costs. CONCLUSIONS: Hepatic metastasectomy is a cost-effective option for selected patients with metachronous CRC metastases limited to the liver. When considering metastasectomy, more aggressive approaches are generally preferred to less aggressive approaches. Overall, surgeons should be encouraged to consider resection for all patients whose metastases can technically be removed.     

Influence of presentation on outcome in abdominal aortic aneurysm repair.

OBJECTIVES: In the absence of formal screening abdominal aortic aneurysms (AAA) are detected in an opportunistic manner. Many remain asymptomatic and undetected until they rupture. Incidentally discovered small AAAs are entered into a surveillance programme until they reach a suitable size for repair. The aim of this study was to examine trends in the management of AAA and whether the method of presentation had an effect on subsequent mortality. DESIGN: Observational study in UK district general hospital. MATERIALS/METHODS: This study reports a single surgeon case series identified using a prospectively maintained database. Data on mode of presentation, management and mortality were retrieved from case notes, PIMS hospital database and the Office of National Statistics. RESULTS: Two hundred and five patients were referred with AAAs between 1992 and 2004, 78% presenting in elective circumstances. The surveillance programme fed 33% of the operated cases. Two aneurysms ruptured whilst under surveillance. Overall elective operative mortality was 11.8% and has progressively decreased over time. Thirty-day operated mortality was significantly lower in patients having a period of surveillance than those having immediate elective repair (2.3 vs. 16.3%, p=0.018). A slight reduction in emergency AAA repairs was noted over the study period (r2=0.6) although registered aneurysm deaths continue to increase (r2=0.83). CONCLUSIONS: Elective mortality following AAA surgery decreased over the study period. Outcome was better in those patients who had surgery for aneurysms that had been under surveillance. Despite opportunistic screening the population adjusted mortality rate of aortic aneurysms showed a progressive increase. A reduction in deaths from aneurysms is unlikely without a formal screening programme.     

Active Surveillance, Radiofrequency Ablation, or Cryoablation for the Nonsurgical Management of a Small Renal Mass: A Cost-Utility Analysis

Background

Patients with a cortical small (≤4 cm) renal mass often are not candidates for or choose not to undergo surgery. The optimal management strategy for such patients is unclear.

Methods

A decision-analytic Markov model was developed from the perspective of a third party payer to compare the quality-adjusted life expectancy and lifetime costs for 67-year-old patients with a small renal mass undergoing premanagement decision biopsy, immediate percutaneous radiofrequency ablation or percutaneous cryoablation (without premanagement biopsy), or active surveillance with serial imaging and subsequent ablation if needed.

Results

The dominant strategy (most effective and least costly) was active surveillance with subsequent cryoablation if needed. On a quality-adjusted and discounted basis, immediate cryoablation resulted in a similar life expectancy (3 days fewer) but cost $3,010 more. This result was sensitive to the relative rate of progression to metastatic disease. Strategies that employed radiofrequency ablation had decreased quality-adjusted life expectancies (82–87 days fewer than the dominant strategy) and higher costs ($3,231–$6,398 more).

Conclusions

Active surveillance with delayed percutaneous cryoablation, if needed, may be a safe and cost-effective alternative to immediate cryoablation. The uncertainty in the relative long-term rate of progression to metastatic disease in patients managed with active surveillance versus immediate cryoablation needs to be weighed against the higher cost of immediate cryoablation. A randomized trial is needed directly to evaluate the nonsurgical management of patients with a small renal mass, and could be limited to the most promising strategies identified in this analysis.