Open versus Endovascular Repair of Abdominal Aortic Aneurysm.

BACKGROUND: Elective endovascular repair of an abdominal aortic aneurysm results in lower perioperative mortality than traditional open repair, but after 4 years this survival advantage is not seen; in addition, results of two European trials have shown worse long-term outcomes with endovascular repair than with open repair. Long-term results of a study we conducted more than a decade ago to compare endovascular repair with open repair are unknown. METHODS: We randomly assigned patients with asymptomatic abdominal aortic aneurysms to either endovascular repair or open repair of the aneurysm. All the patients were candidates for either procedure. Patients were followed for up to 14 years. RESULTS: A total of 881 patients underwent randomization: 444 were assigned to endovascular repair and 437 to open repair. The primary outcome was all-cause mortality. A total of 302 patients (68.0%) in the endovascular-repair group and 306 (70.0%) in the open-repair group died (hazard ratio, 0.96; 95% confidence interval [CI], 0.82 to 1.13). During the first 4 years of follow-up, overall survival appeared to be higher with endovascular repair than with open repair; from year 4 through year 8, overall survival was higher in the open-repair group; and after 8 years, overall survival was once again higher in the endovascular-repair group (hazard ratio for death, 0.94; 95% CI, 0.74 to 1.18). None of these trends were significant. There were 12 aneurysm-related deaths (2.7%) in the endovascular-repair group and 16 (3.7%) in the open-repair group (between-group difference, -1.0 percentage point; 95% CI, -3.3 to 1.4); most deaths occurred during the perioperative period. Aneurysm rupture occurred in 7 patients (1.6%) in the endovascular-repair group, and rupture of a thoracic aneurysm occurred in 1 patient (0.2%) in the open-repair group (between-group difference, 1.3 percentage points; 95% CI, 0.1 to 2.6). Death from chronic obstructive lung disease was just over 50% more common with open repair (5.4% of patients in the endovascular-repair group and 8.2% in the open-repair group died from chronic obstructive lung disease; between-group difference, -2.8 percentage points; 95% CI, -6.2 to 0.5). More patients in the endovascular-repair group underwent secondary procedures. CONCLUSIONS: Long-term overall survival was similar among patients who underwent endovascular repair and those who underwent open repair. A difference between groups was noted in the number of patients who underwent secondary therapeutic procedures. Our results were not consistent with the findings of worse performance of endovascular repair with respect to long-term survival that was seen in the two European trials. (Funded by the Department of Veteran Affairs Office of Research and Development; OVER ClinicalTrials.gov number, NCT00094575.).

Lifetime Risk and Risk Factors for Abdominal Aortic Aneurysm in a 24-Year Prospective Study: The ARIC Study (Atherosclerosis Risk in Communities).

OBJECTIVE: Abdominal aortic aneurysm (AAA) is an important vascular disease in older adults, but data on lifetime risk of AAA are sparse. We examined lifetime risk of AAA in a community-based cohort and prospectively assessed the association between midlife cardiovascular risk factors and AAAs. APPROACH AND RESULTS: In ARIC study (Atherosclerosis Risk in Communities), 15 792 participants were recruited at visit 1 in 1987 to 1989 and followed up through 2013. Longitudinal smoking status was defined using smoking behavior ascertained from visit 1 (1987-1989) to visit 4 (1996-1998). We followed up participants for incident, clinical AAAs using hospital discharge diagnoses, Medicare outpatient diagnoses, or death certificates through 2011 and identified 590 incident AAAs. An abdominal ultrasound was conducted in 2011 to 2013 in 5911 surviving participants, and 75 asymptomatic AAAs were identified. We estimated the lifetime risk of AAA from the index age 45 years through 85 years of age. At age 45, the lifetime risk for AAA was 5.6% (95% confidence interval, 4.8-6.1) and was higher in men (8.2%) and current smokers (10.5%). Smokers who quit smoking between visit 1 and visit 4 had a 29% lower AAA lifetime risk compared with continuous smokers but had a higher risk than pre-visit 1 quitters. The lifetime risk of rupture or medical intervention was 1.6% (95% confidence interval, 1.2-1.8). Smoking, white race, male sex, greater height, and greater low-density lipoprotein or total cholesterol were associated with an increased risk of clinical AAA and asymptomatic AAA. CONCLUSIONS: At least 1 in 9 middle-aged current smokers developed AAA in their lifetime. Smoking cessation reduced the lifetime risk of AAA.

Circulating Biomarkers and Abdominal Aortic Aneurysm Incidence: The Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: The pathogenesis of abdominal aortic aneurysm (AAA) is complex. Cross-sectional studies have connected circulating biomarkers with AAA, but prospective evidence is limited. METHODS AND RESULTS: In the Atherosclerosis Risk in Communities Study cohort, we measured multiple blood biomarkers of inflammation, hemostasis, thrombin generation, cardiac dysfunction, and vascular stiffness and identified incident AAAs during follow-up using hospital discharge codes. Six biomarkers (white blood cell count, fibrinogen, D-dimer, troponin T, N-terminal pro-brain natriuretic peptide, and high-sensitivity C-reactive protein) were strongly associated positively with AAA incidence. Compared with having none of these 6 biomarkers in the highest quartile, the hazard ratios of AAA for those with 1, 2, 3, or 4 to 6 biomarkers in the highest quartile were 2.2, 3.3, 4.0, and 9.9, respectively (P for trend < 0.0001) after adjustment for other risk factors. CONCLUSIONS: This prospective study found that higher concentrations of 6 biomarkers were associated with increased risk of AAA. The more markers that fell into the highest quartile, the higher the AAA risk was. Multiple positive biomarkers identify a subgroup of patients at high risk of AAA.

Long-term mortality after screening for colorectal cancer.

BACKGROUND: In randomized trials, fecal occult-blood testing reduces mortality from colorectal cancer. However, the duration of the benefit is unknown, as are the effects specific to age and sex. METHODS: In the Minnesota Colon Cancer Control Study, 46,551 participants, 50 to 80 years of age, were randomly assigned to usual care (control) or to annual or biennial screening with fecal occult-blood testing. Screening was performed from 1976 through 1982 and from 1986 through 1992. We used the National Death Index to obtain updated information on the vital status of participants and to determine causes of death through 2008. RESULTS: Through 30 years of follow-up, 33,020 participants (70.9%) died. A total of 732 deaths were attributed to colorectal cancer: 200 of the 11,072 deaths (1.8%) in the annual-screening group, 237 of the 11,004 deaths (2.2%) in the biennial-screening group, and 295 of the 10,944 deaths (2.7%) in the control group. Screening reduced colorectal-cancer mortality (relative risk with annual screening, 0.68; 95% confidence interval [CI], 0.56 to 0.82; relative risk with biennial screening, 0.78; 95% CI, 0.65 to 0.93) through 30 years of follow-up. No reduction was observed in all-cause mortality (relative risk with annual screening, 1.00; 95% CI, 0.99 to 1.01; relative risk with biennial screening, 0.99; 95% CI, 0.98 to 1.01). The reduction in colorectal-cancer mortality was larger for men than for women in the biennial-screening group (P=0.04 for interaction). CONCLUSIONS: The effect of screening with fecal occult-blood testing on colorectal-cancer mortality persists after 30 years but does not influence all-cause mortality. The sustained reduction in colorectal-cancer mortality supports the effect of polypectomy. (Funded by the Veterans Affairs Merit Review Award Program and others.).

Longer Withdrawal Time Is Associated With a Reduced Incidence of Interval Cancer After Screening Colonoscopy.

BACKGROUND & AIMS: Withdrawal times and adenoma detection rates are widely used quality indicators for screening colonoscopy. More rapid withdrawal times have been associated with undetected adenomas, which can increase risk for interval colorectal cancer. METHODS: We analyzed records of 76,810 screening colonoscopies performed between 2004 and 2009, by 51 gastroenterologists practicing in Minneapolis and St Paul, MN. Colonoscopy records were linked electronically to the state cancer registry (Minnesota Cancer Surveillance System) to identify incident interval cancers that were diagnosed within 5.5 years after the screening examination. RESULTS: The physicians' mean ± SD withdrawal time was 8.6 ± 1.7 minutes and adenoma detection rates were 25% ± 9%. Longer mean withdrawal times were associated with higher adenoma detection rates (3.6% per minute; 95% confidence interval: 2.4% to 4.8%; P < .0001). We identified 78 cancers during 410,687 person-years of follow-up, for an annual rate of 0.19/1000 person-years. Physicians' mean annual withdrawal times were inversely associated with cancer incidence (P < .0001). Compared with withdrawal times ≥6 minutes, the adjusted incidence rate ratio for withdrawal times of <6 minutes was 2.3 (95% confidence interval: 1.5-3.4; P < .0001). CONCLUSIONS: Shorter mean annual withdrawal times during screening colonoscopies were independently associated with lower adenoma detection rates and increased risk of interval colorectal cancer.

Long-term comparison of endovascular and open repair of abdominal aortic aneurysm.

BACKGROUND: Whether elective endovascular repair of abdominal aortic aneurysm reduces long-term morbidity and mortality, as compared with traditional open repair, remains uncertain. METHODS: We randomly assigned 881 patients with asymptomatic abdominal aortic aneurysms who were candidates for both procedures to either endovascular repair (444) or open repair (437) and followed them for up to 9 years (mean, 5.2). Patients were selected from 42 Veterans Affairs medical centers and were 49 years of age or older at the time of registration. RESULTS: More than 95% of the patients underwent the assigned repair. For the primary outcome of all-cause mortality, 146 deaths occurred in each group (hazard ratio with endovascular repair versus open repair, 0.97; 95% confidence interval [CI], 0.77 to 1.22; P=0.81). The previously reported reduction in perioperative mortality with endovascular repair was sustained at 2 years (hazard ratio, 0.63; 95% CI, 0.40 to 0.98; P=0.04) and at 3 years (hazard ratio, 0.72; 95% CI, 0.51 to 1.00; P=0.05) but not thereafter. There were 10 aneurysm-related deaths in the endovascular-repair group (2.3%) versus 16 in the open-repair group (3.7%) (P=0.22). Six aneurysm ruptures were confirmed in the endovascular-repair group versus none in the open-repair group (P=0.03). A significant interaction was observed between age and type of treatment (P=0.006); survival was increased among patients under 70 years of age in the endovascular-repair group but tended to be better among those 70 years of age or older in the open-repair group. CONCLUSIONS: Endovascular repair and open repair resulted in similar long-term survival. The perioperative survival advantage with endovascular repair was sustained for several years, but rupture after repair remained a concern. Endovascular repair led to increased long-term survival among younger patients but not among older patients, for whom a greater benefit from the endovascular approach had been expected. (Funded by the Department of Veterans Affairs Office of Research and Development; OVER ClinicalTrials.gov number, NCT00094575.).

Predictors and outcomes of endoleaks in the Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms.

OBJECTIVE: The Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms study was a randomized controlled trial comparing open vs endovascular repair (EVAR) in standard-risk patients with infrarenal aortic aneurysms. The analysis reported here identifies characteristics, risk factors, and long-term outcome of endoleaks in patients treated with EVAR in the OVER cohort. METHODS: The OVER trial enrolled 881 patients, of whom 439 received successful EVAR. Logistic regression analysis was used to identify predictors for endoleaks and secondary interventions. Kaplan-Meier survival analysis, longitudinal plots, and generalized linear mixed models methods were used to describe time to endoleak detection, resolution, or death. RESULTS: During a mean follow-up of 6.2 ± 2.4 years, 135 patients (30.5%) developed 187 endoleaks. Four patients with EVAR went on to rupture; these four patients did not all have an endoleak. Mortality between patients who did and did not develop endoleaks was not significantly different. The 187 endoleaks included 12% type I, 76% type II, 3% type III, 3% type IV, and 6% indeterminate. Patient demographics and vascular risk factors were not associated with endoleak development. The presence of endoleaks resulted in an increase in aneurysm diameter over time (P < .0001). Fifty-three percent of endoleaks resolved spontaneously, and 31.9% received secondary interventions. The initial aneurysm size independently predicted a need for secondary interventions (P < .0003). Delayed type II endoleaks (detected >1 year after EVAR) were associated with aneurysm enlargement compared with the early counterpart. There was no difference in aneurysm size or length of survival between type II and other types of endoleak. CONCLUSIONS: We present one of the most comprehensive and longest follow-up analyses of patients treated with aortic endografts. Endoleaks were common and negatively affected aneurysm diameter reduction. Delayed type II endoleaks were associated with late aneurysm diameter enlargement. Endoleaks and aneurysm diameter enlargement were not associated with excess mortality compared with those without these features.

Costs of repair of abdominal aortic aneurysm with different devices in a multicenter randomized trial.

OBJECTIVE: Prior analysis in the Open vs Endovascular Repair Veterans Affairs (VA) Cooperative Study (CSP #498) demonstrated that survival, quality of life, and total health care costs are not significantly different between the open and endovascular methods of repair of abdominal aortic aneurysm. The device is a major cost of this method of repair, and the objective of this study was to evaluate the costs of the device, abdominal aortic aneurysm repair, and total health care costs when different endograft systems are selected for the endovascular repair (EVR). Within each selected system, EVR costs are compared with open repair costs. METHODS: The study randomized 881 patients to open (n = 437) or EVR (n = 444). Device selection was recorded before randomization; therefore, open repair controls were matched to each device cohort. Data were excluded for two low-volume devices, implanted in only 13 individuals, leaving 423 control and 431 endovascular patients: 166 Zenith (Cook Medical, Bloomington, Ind), 177 Excluder (W. L. Gore & Associates, Flagstaff, Ariz), and 88 AneuRx (Medtronic, Minneapolis, Minn). Mean device, hospitalization, and total health care costs from randomization to 2 years were compared. Health care utilization data were obtained from patients and national VA and Medicare data sources. VA costs were determined using methods previously developed by the VA Health Economics Resource Center. Non-VA costs were obtained from Medicare claims data and billing data from the patient's health care providers. RESULTS: Implant costs were 38% of initial hospitalization costs. Mean device (range, $13,600-$14,400), initial hospitalization (range, $34,800-$38,900), and total health care costs at 2 years in the endovascular (range, $72,400-$78,200) and open repair groups (range, $75,600-$82,100) were not significantly different among device systems. Differences between endovascular and corresponding open repair cohorts showed lower mean costs for EVR (range, $3200-$8300), but these were not statistically different. CONCLUSIONS: The implant costs of endovascular aneurysm repair are substantial. When evaluating total health care system expenditures, there is large individual variability in costs, and there is no significant difference at 2 years among systems or when an individual system is compared with open repair.

Screening for liver cancer: the rush to judgment.

In 2005, a professional society issued a level I recommendation to use ultrasonography to screen the 3 million Americans with cirrhosis for hepatocellular carcinoma (HCC) every 6 months. This designation was based on a large randomized trial from China that reported a reduction in HCC deaths from screening in carriers of hepatitis B surface antigen. However, besides the difference in population, this trial did not report all deaths, excluded patients after randomization, and would almost certainly have found no significant difference if the cluster randomization had been accounted for in the analysis. Misplaced confidence in the Chinese trial has led many writers to accept the effectiveness of HCC screening as proven, making it more difficult to conduct the high-quality randomized trials that are needed to ensure optimal patient care.

Cost-effectiveness of open versus endovascular repair of abdominal aortic aneurysm in the OVER trial.

OBJECTIVE: This study was conducted to determine the costs and comparative cost-effectiveness of two methods of abdominal aortic aneurysm (AAA) repair in the Open Versus Endovascular Repair (OVER) Veterans Affairs (VA) Cooperative Study, a multicenter randomized trial of 881 patients. METHODS: The primary outcomes of this analysis were mean total health care cost per life-year and per quality-adjusted life-year (QALY) from randomization to 2 years after. QALYs were calculated from EuroQol (EQ)-5D questionnaires collected at baseline and annually. Health care utilization data were obtained directly from patients and from national VA and Medicare data sources. VA costs were obtained from national VA sources using methods previously developed by the VA Health Economics Resource Center. Costs for non-VA care were determined from Medicare claims data or billing data from the patient's health care providers. RESULTS: After 2 years of follow-up, mean life-years were 1.78 in the endovascular repair group and 1.74 in the open repair group (difference, 0.04; 95% confidence interval [CI], -0.03 to 0.09; P = .29). Mean QALYs were 1.462 in the endovascular group and 1.461 in the open group (difference adjusting for baseline EQ-5D score, 0.006; 95% CI, -0.038 to 0.052; P = .78). Mean graft costs were higher in the endovascular group ($14,052 vs $1363; P < .001), but length of stay was shorter (5.0 vs 10.5 days; P < .001), resulting in a lower mean cost of the hospital admission for the AAA procedure in the endovascular repair group of $37,068 vs $42,970 (difference, -$5901; 95% CI, -$12,135 to -$821; P = .04). After 2 years, total health care costs remained lower in the endovascular group, but the difference was no longer significant (-$5019; 95% CI, -$16,720 to $4928; P = .35). The probability of endovascular repair being less costly and more effective was 70.9% for life-years and 51.4% for QALYs. CONCLUSIONS: In this multicenter randomized trial, endovascular AAA repair resulted in lower cost and better survival than open repair after the initial hospitalization for repair; but after 2 years, survival, quality of life, and costs were not significantly different between the two treatments.

Is ulcerative colitis associated with survival among older persons with colorectal cancer in the US? A population-based case-control study.

BACKGROUND: While ulcerative colitis (UC) is a risk factor for colorectal cancer, the association of UC with survival after colorectal cancer has not been studied in an older population. AIMS: The objective of our study was to compare the survival of colorectal cancer between persons with and without UC. METHODS: All cases of colorectal cancer (CRC) in persons 67 and older residing in a SEER catchment area and enrolled in the Medicare between 1993 and 1999 were assessed. We identified diagnosis of UC using ICD-9 codes on Medicare outpatient, office, and inpatient claims in the 2 years prior to the date of diagnosis. We used Cox proportional hazards model and Kaplan-Meier curves to compare survival between individuals with UC and CRC (UC-CRC) and sporadic CRC RESULTS: We identified 47,543 cases of colorectal cancer. Cases with UC-CRC tend to be diagnosed at earlier stages compared to sporadic CRC (42 vs. 37% local (TNM stage 1 and 2) and 11 vs. 17% distant spread (TNM stage 4), respectively; P value = 0.04). Controlling for age, gender, race and stage, diagnosis of UC did not affect the 3-year survival for CRC. CONCLUSIONS: Colorectal cancers tend to be diagnosed at earlier stages among persons with UC, but there is no difference in 3-year survival rates for colorectal cancer among individuals with and without UC.

Venous thromboembolism prophylaxis in hospitalized medical patients and those with stroke: a background review for an American College of Physicians Clinical Practice Guideline.

BACKGROUND: Venous thromboembolism prophylaxis has been recommended for nonsurgical patients, but its effectiveness remains uncertain. PURPOSE: To assess the benefits and harms of prophylaxis in hospitalized adult medical patients and those with acute stroke. DATA SOURCES: MEDLINE and the Cochrane Library from 1950 through April 2011, reference lists, and study authors. STUDY SELECTION: English-language randomized trials were included if they provided clinical outcomes and evaluated therapy with low-dose heparin or related agents or mechanical measures compared with placebo, no treatment, or other active prophylaxis in the target population. DATA EXTRACTION: Two independent investigators extracted data on study characteristics and clinical outcomes up to 120 days after randomization. The primary outcome was total mortality. DATA SYNTHESIS: In medical patients, heparin prophylaxis did not reduce total mortality but did result in fewer pulmonary embolisms (PEs) (odds ratio [OR], 0.69 [95% CI, 0.52 to 0.90], but with evidence of publication bias) and an increase in all bleeding events (risk ratio [RR], 1.34 [CI, 1.08 to 1.66]). Heparin prophylaxis had no statistically significant effect on any outcome in patients with acute stroke except for an increase in major bleeding events (OR, 1.66 [CI, 1.20 to 2.28]). When trials of medical patients and those with stroke were considered together (18 studies; 36,122 patients), heparin prophylaxis reduced the incidence of PE (OR, 0.70 [CI, 0.56 to 0.87]; absolute reduction, 3 events per 1000 patients treated [CI, 1 to 5 events]) but increased the incidence of all bleeding (RR, 1.28 [CI, 1.05 to 1.56]) and major bleeding events (OR, 1.61 [CI, 1.23 to 2.10]), with an absolute increase of 9 bleeding events per 1000 patients treated (CI, 2 to 18 events), 4 of which were major (CI, 1 to 7 events). A reduction in total mortality approached statistical significance (RR, 0.93 [CI, 0.86 to 1.00]; P = 0.056; absolute decrease, 6 deaths per 1000 patients treated [CI, 0 to 11 deaths]). No statistically significant differences in clinical outcomes were observed in the 14 trials that compared unfractionated heparin with low-molecular-weight heparin. No improvements in clinical outcomes were seen in the 3 studies of mechanical prophylaxis in patients with stroke, but more patients had lower-extremity skin damage (RR, 4.02 [CI, 2.34 to 6.91])-an increase of 39 events per 1000 patients treated (CI, 17 to 77 events). LIMITATION: Non-English-language studies were not included, but these were few and small. CONCLUSION: Heparin prophylaxis had no significant effect on mortality, may have reduced PE in medical patients and all patients combined, and led to more bleeding and major bleeding events, thus resulting in little or no net benefit. No differences in benefits or harms were found according to type of heparin used. Mechanical prophylaxis provided no benefit and resulted in clinically important harm to patients with stroke. PRIMARY FUNDING SOURCE: American College of Physicians.

The effect of ticagrelor on growth of small abdominal aortic aneurysms-a randomized controlled trial.

AIMS: To evaluate if ticagrelor, an effective platelet inhibitor without known non-responders, could inhibit growth of small abdominal aortic aneurysms (AAAs). METHODS AND RESULTS: In this multi-centre randomized controlled trial, double-blinded for ticagrelor and placebo, acetylic salicylic acid naïve patients with AAA and with a maximum aortic diameter 35-49 mm were included. The primary outcome was mean reduction in log-transformed AAA volume growth rate (%) measured with magnetic resonance imaging (MRI) at 12 months compared with baseline. Secondary outcomes include AAA-diameter growth rate and intraluminal thrombus (ILT) volume enlargement rate. A total of 144 patients from eight Swedish centres were randomized (72 in each group). MRI AAA volume increase was 9.1% for the ticagrelor group and 7.5% for the placebo group (P = 0.205) based on intention-to-treat analysis, and 8.5% vs. 7.4% in a per-protocol analysis (P = 0.372). MRI diameter change was 2.5 mm vs. 1.8 mm (P = 0.113), US diameter change 2.3 mm vs. 2.2 mm (P = 0.778), and ILT volume change 12.9% vs. 10.4% (P = 0.590). CONCLUSION: In this RCT, platelet inhibition with ticagrelor did not reduce growth of small AAAs. Whether the ILT has an important pathophysiological role for AAA growth cannot be determined based on this study due to the observed lack of thrombus modulating effect of ticagrelor. TRIAL REGISTRATION: The TicAAA trial is registered at the US National Institutes of Health (ClinicalTrials.gov) #NCT02070653.