Abstract 170: Worse Patency in Women After Endovascular Peripheral Vascular Intervention

Objectives: Women are suspected to have worse outcomes after lower extremity revascularization. We sought to study how patency differed among men and women undergoing endovascular peripheral vascular intervention (PVI).

Methods: We studied patients in the Vascular Quality Initiative who underwent a PVI (angioplasty, stent, or atherectomy) between January 2010 to October 2016. We excluded all reinterventions on a previously treated artery. The primary exposure was gender (men vs women) and our outcomes were reintervention or occlusion in each artery treated. We studied outcomes through 1-year post-procedure using Kaplan Meier survival analysis and Cox regression, stratified by artery treated. We adjusted for patient demographics and disease characteristics.

Results: Our cohort included 106,073 eligible arteries treated in 58,247 patients across 66,045 procedures. Among these patients, the mean age was 68 years old, 15% were African-American, and 41% were women. Half (50%) of the arteries were treated with stents, 39% were treated with PTA alone, and 11% were treated with atherectomy. Follow-up data on patency was available in 64% of patients (n=37,442 patients, 67,292 arteries). Women experienced lower reintervention-free survival in the iliac (98.4% vs 98.8%, log rank p=0.01) and femoropopliteal (94.7% vs 95.6%, log rank p<0.001) vascular beds ( Figure ). After adjusted Cox regression, gender difference in the femoropopliteal arteries alone remained statistically significant, where women were 30% more likely to need reintervention to maintain artery patency than men (HR: 1.31, 95% CI: 1.18-1.44). Similarly, women experienced lower occlusion-free survival in iliac (95.0% vs 95.9%, log rank p<0.001) and femoropopliteal (88.5% vs 90.9%, log rank p<0.001) arteries. Again, after adjustment, the gender difference remained statistically significant only in the femoropopliteal arteries, where women were 33% more likely than men to have an artery occlude after intervention (HR: 1.33, 95% CI: 1.16-1.53).

Conclusions: Women undergoing PVI in the femoropopliteal arteries are more likely to develop an occlusion or need a reintervention in the treated artery within 1-year after intervention. We need further research and improved follow-up data on patency to understand how and why these sex differences arise.

Claims-based surveillance for reintervention after endovascular aneurysm repair among non-Medicare patients

OBJECTIVE

Many patients who undergo endovascular aortic aneurysm repair (EVR) also undergo repeat procedures, or reinterventions, to address suboptimal device performance and prevent aneurysm rupture. Quality improvement initiatives measuring reintervention after EVR has focused on fee-for-service Medicare patients. However, because patients aged less than 65 years and those with Medicare Advantage represent an important growing subgroup, we used a novel approach leveraging a state data source that captures patients of all ages and with all types of insurance.

METHODS

We identified patients who underwent EVR (2011-2015) within the Vascular Quality Initiative registry and were also listed in the Statewide Planning and Research Cooperative System all-payer claims database of New York. We linked patients in the Vascular Quality Initiative to their Statewide Planning and Research Cooperative System claims file at the patient level with a 96% match rate. We compared outcomes between fee-for-service Medicare eligible, defined as age 65 or older or on dialysis, versus ineligible patients, defined as those younger than 65 and not on dialysis. Our primary outcome was reintervention. We used Cox proportional hazards regression and propensity score matching for risk adjustment.

RESULTS

We studied 1285 patients with a median follow-up of 16 months (range, 1-57 months). The mean age was 74 years, 79% were male, and 84% of procedures were elective. Nearly one in six patients were not Medicare eligible (14%), and the remainder (86%) were Medicare eligible. Medicare-eligible patients were less likely to be male (77% vs 91%; P < .001), have a history of smoking (79% vs 93%; P < .001), and have a nonelective procedure (15% vs 23%; P = .013). The 3-year Kaplan-Meier rate of reintervention was 21%. We found similar rates of reintervention between Medicare-eligible patients and those who were not (19% vs 20%, log-rank P = .199; unadjusted hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.49-1.16). This finding persisted in both the adjusted and propensity-matched analyses (adjusted HR, 0.82; 95% CI, 0.50-1.34; propensity-matched HR, 0.70; 95% CI, 0.36-1.37).

CONCLUSIONS

Reintervention can be monitored using administrative claims from both Medicare and non-Medicare payers, and serve as an important outcome metric after EVR in patients of all ages. The rate of reintervention seems to be similar between older, Medicare-eligible individuals, and those who are not yet eligible.

Regional variation in use and outcomes of combined carotid endarterectomy and coronary artery bypass

OBJECTIVE

In treating concomitant carotid and coronary disease, some recommend staged carotid endarterectomy (CEA) and coronary artery bypass grafting, whereas others favor the combined approach (CCAB). Pressure to reduce surgical variation and to improve quality is real, yet little is known about how geographic practice differences affect outcomes. Using the Vascular Quality Initiative (VQI), this study evaluated regional variation in use and outcomes of CCAB.

METHODS

All CCAB procedures in the VQI from 2003 to 2017 were reviewed and stratified into four regions, as defined by the United States Census Bureau. Primary outcomes included perioperative stroke, death, myocardial infarction (MI), and these as composite (SDM). A χ² analysis was performed.

RESULTS

There were 1495 CCAB procedures identified, representing 1.8% of the VQI CEAs. Regions included the following: Midwest (MW), 32%; Northeast (NE), 39%; South (S), 25%; and West (W), 4%. Most were male (70%) and white (92%). There was significant regional variation in proportional volume of CCABs to all CEAs (0.7% [W] to 2.5% [MW]; P < .001). Regional variation in patch use (78% [W] to 93% [MW]; P < .001), shunting (29% [W] to 71% [MW]; P < .001), and electroencephalography monitoring (13% [W] to 52% [NE]; P < .001) was also significant. Overall perioperative stroke was 3.6%; death, 3.0%; and SDM, 6.8%. No regional difference was seen in outcomes of mortality (1.5% [MW] to 4.2% [NE]; P = .05), stroke (2.8% [NE] to 4.4% [MW]; P = .52), and MI (0.6% [MW] to 1.8% [W]; P = .62). When the Bonferroni correction was used, there remained no difference in stroke, MI, or SDM across regions, but mortality became significant. Using the Society for Vascular Surgery guidelines for consideration of CCAB, the minority of patients fell within the symptomatic carotid stenosis (SYMP, 15%; n = 218) or severe (≥70%) asymptomatic bilateral carotid disease (BIL, 18%; n = 267) categories. The most common indication was asymptomatic unilateral severe carotid stenosis (UNI, 37%; n = 552). There were no differences in regional outcomes stratified by indication (SYMP, BIL, UNI). Overall, when SYMP and BIL were compared with UNI, UNI had lower rates of stroke (2.4% vs 4.9%; P = .03) but similar MI (0.7% vs 1.2%; P = .40) and mortality (2.2% vs 2.5%; P = .75).

CONCLUSIONS

Significant variation exists across VQI centers in the use of CCAB. Despite differences in volume and practices, regional perioperative outcomes are similar. UNI is the most commonly used indication and has lower stroke rates relative to SYMP and BIL. CCAB is performed well across the United States, but most patients fall outside of Society for Vascular Surgery guidelines.

Cardiovascular morbidity and mortality after aortic dissection, intramural hematoma, and penetrating aortic ulcer

OBJECTIVE

The nonaortic cardiovascular morbidity and mortality of patients with aortic dissection (AD), intramural hematoma (IMH), and penetrating aortic ulcer (PAU) is unknown. We aimed to define the rates of cardiovascular (CV) events in a cohort of patients with newly diagnosed AD, IMH, and PAU.

METHODS

We performed a retrospective review of all Olmsted County, Minnesota, residents diagnosed with AD, IMH, and PAU from 1995 to 2015. The primary outcome was nonaortic CV death. The secondary outcome was a first-time nonfatal CV event (myocardial infarction, heart failure [HF], or stroke). The outcomes were compared with age- and sex-matched population referents using Cox proportional hazards regression, with adjustment for comorbidities.

RESULTS

A total of 133 patients (77 with AD, 21 with IMH, 35 with PAU; 57% male) with a mean age of 71.8 ± 14.1 years were identified. The median follow-up was 10 years. Compared with the population referents, the patients with AD/IMH/PAU had an increased risk of CV death (adjusted hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.4-4.2; P = .003) and an increased risk of any first-time nonfatal CV event (adjusted HR, 3.0; 95% CI, 1.9-4.8; P < .001), mainly resulting from an increased risk of first-time HF (adjusted HR, 2.7; 95% CI, 1.7-4.3; P < .001). When excluding events within 14 days of the diagnosis, the patients with AD/IMH/PAU remained at increased risk of CV death (adjusted HR, 2.6; 95% CI, 1.4-4.7; P = .002), any first-time nonfatal CV event (adjusted HR, 2.6; 95% CI, 1.5-4.4, P <.001), and first-time HF (adjusted HR 2.5, 95% CI 1.5-4.3; P < .001).

CONCLUSIONS

Compared with the population referents, the patients with AD/IMH/PAU had a two- to threefold risk of nonaortic CV death, any first-time nonfatal CV event, and first-time HF. These data implicate the need for long-term cardiovascular management for patients with AD/IMH/PAU.

National practice trends for the surgical management of lung cancer in the CMS population: an atlas of care

BACKGROUND

Video-assisted thoracoscopic surgery (VATS) has been established as a safe and effective alternative to an open approach for the treatment of early-stage lung cancer. Despite this, differences in utilization across the nation are present. The aims of this study were to: (I) characterize trends in the use of open surgery and VATS for the management of lung cancer across the United States, and (II) describe if particular regions of the country utilize minimally invasive surgery more frequently.

METHODS

We studied all Medicare beneficiaries from the ages of 65 to 99 years with full Part A and B coverage and no HMO coverage for the years of 2006 and 2014 (the most recent year available at the time of this analysis). Beneficiaries with a diagnosis of lung cancer (ICD-9 codes: 162.0 162.2 162.3 162.4 162.5 162.8 162.9) were selected. Rates of thoracoscopic surgery (CPT codes: 32663, 32666, 32667, 32668, 32669, 32670, 32671) and open lung resections (32505, 32506, 32507, 32608, 32440, 32442, 32445, 32480, 32482, 32484, 32486, 32488) were calculated by year and region. Rates in 2006 and 2014 with descriptive statistics and a univariate analysis were performed using Student's t-test and chi-square, as appropriate. A two-sided P value <0.05 was considered statistically significant.

RESULTS

A total of 24,368,333 and 23,921,059 beneficiaries for the years of 2006 and 2014 were analyzed. A diagnosis of lung cancer was detected in claims of 167,418 patients (0.7%) in 2006 and 167,506 patients in 2014 (0.7%), which was not significantly different (P=0.7). Among these lung cancer patients, a surgical intervention was performed in 17,249 patients (10.3%) during 2006 and 18,603 patients (11.1%) in 2014 (P=0.01). Among those undergoing surgery, a VATS approach was performed in 2,512 patients (15%) during 2006 and 9,578 patients (54%) during 2014 (P=0.001). In 2006, California, New York, and New Jersey performed the most VATS procedures, in comparison to 2014, when New York, Florida, and California performed the highest number of VATS procedures.

CONCLUSIONS

While the prevalence of lung cancer in the United States was unchanged between 2006 and 2014, the use of VATS techniques increased five-fold. Further studies to better understand the adoption or availability of new surgical techniques in lung cancer populations across geographic regions and patient populations are necessary.

A Review of Decision Aids for Patients Considering More Than One Type of Invasive Treatment

With continuous advances in medicine, patients are faced with several medical or surgical treatment options for their health conditions. Decision aids may be useful in helping patients navigate these options and choose based on their goals and values. We reviewed the literature to identify decision aids and better understand the effect on patient decision-making. We identified 107 decision aids designed to help patients make decisions between medical treatment or screening options; 39 decision aids were used to help patients choose between a medical and surgical treatment, and five were identified that aided patients in deciding between a major open surgical procedure and a less invasive option. Many of the decision aids were used to help patients decide between prostate, colorectal, and breast cancer screening or treatment options. Although most decision aids were not associated with a significant effect on the actual decision made, they were largely associated with increased patient knowledge, decreased decisional conflict, more accurate perception of risks, increased satisfaction with their decision, and no increase in anxiety surrounding their decision. These data identify a gap in use of decision aids in surgical decision-making and highlight the potential to help surgical patients make value-based, knowledgeable decisions regarding their treatment.

Comparing Long-term Mortality After Carotid Endarterectomy vs Carotid Stenting Using a Novel Instrumental Variable Method for Risk Adjustment in Observational Time-to-Event Data

IMPORTANCE

Choosing between competing treatment options is difficult for patients and clinicians when results from randomized and observational studies are discordant. Observational real-world studies yield more generalizable evidence for decision making than randomized clinical trials, but unmeasured confounding, especially in time-to-event analyses, can limit validity.

OBJECTIVES

To compare long-term survival after carotid endarterectomy (CEA) and carotid artery stenting (CAS) in real-world practice using a novel instrumental variable method designed for time-to-event outcomes, and to compare the results with traditional risk-adjustment models used in observational research for survival analyses.

DESIGN, SETTING, AND PARTICIPANTS

A multicenter cohort study was performed. The Vascular Quality Initiative, an observational quality improvement registry, was used to compare long-term mortality after CEA vs CAS. The study included 86 017 patients who underwent CEA (n = 73 312) or CAS (n = 12 705) between January 1, 2003, and December 31, 2016. Patients were followed up for long-term mortality assessment by linking the registry data to Medicare claims. Medicare claims data were available through September 31, 2015.

EXPOSURE

Procedure type (CEA vs CAS).

MAIN OUTCOMES AND MEASURES

The hazard ratios (HRs) of all-cause mortality using unadjusted, adjusted, propensity-matched, and instrumental variable methods were examined. The instrumental variable was the proportion of CEA among the total carotid procedures (endarterectomy and stenting) performed at each hospital in the 12 months before each patient's index operation and therefore varies over the study period.

RESULTS

Participants who underwent CEA had a mean (SD) age of 70.3 (9.4) years compared with 69.1 (10.4) years for CAS, and most were men (44 191 [60.4%] for CEA and 8117 [63.9%] for CAS). The observed 5-year mortality was 12.8% (95% CI, 12.5%-13.2%) for CEA and 17.0% (95% CI, 16.0%-18.1%) for CAS. The unadjusted HR of mortality for CEA vs CAS was 0.67 (95% CI, 0.64-0.71), and Cox-adjusted and propensity-matched HRs were similar (0.69; 95% CI, 0.65-0.74 and 0.71; 95% CI, 0.65-0.77, respectively). These findings are comparable with published observational studies of CEA vs CAS. However, the association between CEA and mortality was more modest when estimated by instrumental variable analysis (HR, 0.83; 95% CI, 0.70-0.98), a finding similar to data reported in randomized clinical trials.

CONCLUSIONS AND RELEVANCE

The study found a survival advantage associated with CEA over CAS in unadjusted and Cox-adjusted analyses. However, this finding was more modest when using an instrumental variable method designed for time-to-event outcomes for risk adjustment. The instrumental variable-based results were more similar to findings from randomized clinical trials, suggesting this method may provide less biased estimates of time-dependent outcomes in observational analyses.

Extent of Risk-Aligned Surveillance for Cancer Recurrence Among Patients With Early-Stage Bladder Cancer

IMPORTANCE

Cancer care guidelines recommend aligning surveillance frequency with underlying cancer risk, ie, more frequent surveillance for patients at high vs low risk of cancer recurrence.

OBJECTIVE

To assess the extent to which such risk-aligned surveillance is practiced within US Department of Veterans Affairs facilities by classifying surveillance patterns for low- vs high-risk patients with early-stage bladder cancer.

DESIGN SETTING AND PARTICIPANTS

US national retrospective cohort study of a population-based sample of patients diagnosed with low-risk or high-risk early-stage bladder between January 1, 2005, and December 31, 2011, with follow-up through December 31, 2014. Analyses were performed March 2017 to April 2018. The study included all Veterans Affairs facilities (n = 85) where both low-and high-risk patients were treated.

EXPOSURES

Low-risk vs high-risk cancer status, based on definitions from the European Association of Urology risk stratification guidelines and on data extracted from diagnostic pathology reports via validated natural language processing algorithms.

MAIN OUTCOMES AND MEASURES

Adjusted cystoscopy frequency for low-risk and high-risk patients for each facility, estimated using multilevel modeling.

RESULTS

The study included 1278 low-risk and 2115 high-risk patients (median [interquartile range] age, 77 [71-82] years; 99% [3368 of 3393] male). Across facilities, the adjusted frequency of surveillance cystoscopy ranged from 3.7 to 6.2 (mean, 4.8) procedures over 2 years per patient for low-risk patients and from 4.6 to 6.0 (mean, 5.4) procedures over 2 years per patient for high-risk patients. In 70 of 85 facilities, surveillance was performed at a comparable frequency for low- and high-risk patients, differing by less than 1 cystoscopy over 2 years. Surveillance frequency among high-risk patients statistically significantly exceeded surveillance among low-risk patients at only 4 facilities. Across all facilities, surveillance frequencies for low- vs high-risk patients were moderately strongly correlated (r = 0.52; P < .001).

CONCLUSIONS AND RELEVANCE

Patients with early-stage bladder cancer undergo cystoscopic surveillance at comparable frequencies regardless of risk. This finding highlights the need to understand barriers to risk-aligned surveillance with the goal of making it easier for clinicians to deliver it in routine practice.

Military Service and Decision Quality in the Management of Knee Osteoarthritis

Background

Decision quality measures the degree to which care decisions are knowledge-based and value-aligned. Because military service emphasizes hierarchy, command, and mandates some healthcare decisions, military service may attenuate patient autonomy in healthcare decisions and lower decision quality. VA is the nation's largest provider of orthopedic care. We compared decision quality in a sample of VA and non-VA patients seeking care for knee osteoarthritis.

Methods

Our study sample consisted of patients newly referred to our orthopedic clinic for the management of knee osteoarthritis. None of the study patients were exposed to a knee osteoarthritis decision aid. Consenting patients were administered the Hip/Knee Decision Quality Instrument (HK-DQI). In addition, they were surveyed about decision-making preferences and demographics. We compared results to a non-VA cohort from our academic institution's arthroplasty database.

Results

The HK-DQI Knowledge Score was lower in the VA cohort (45%, SD = 22, n = 25) compared with the non-VA cohort (53%, SD = 21, n = 177) (p = 0.04). The Concordance Score was lower in the VA cohort (36%, SD = 49%) compared with the control cohort (70%, SD 46%) (p = 0.003). Non-VA patients were more likely to make a high-quality decision (p = 0.05). Non-VA patients were more likely to favor a shared decision-making process (p = 0.002).

Conclusions

Decision quality is lower in Veterans with knee osteoarthritis compared with civilians, placing them at risk for lower treatment satisfaction and possibly unwarranted surgical utilization. Our future work will examine if this difference is from conditioned military service behaviors or confounding demographic factors, and if conventional shared decision-making techniques will correct this deficiency.

Patients with end-stage renal disease have poor outcomes after endovascular abdominal aortic aneurysm repair

OBJECTIVE

Although endovascular repair of abdominal aortic aneurysms (AAAs) has been demonstrated to have favorable outcomes, not all cohorts of patients with AAA fare equally well. Our goal was to investigate perioperative and 1-year outcomes in patients with end-stage renal disease (ESRD) on dialysis, who have traditionally fared worse after vascular interventions, to assess how ESRD affects outcomes in a large modern cohort of endovascular aneurysm repair (EVAR) patients.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing EVAR from 2010 to 2017. ESRD patients were compared with patients not on dialysis. Propensity-matched scoring and multivariable analysis were used to isolate the effects of ESRD.

RESULTS

Of 28,683 EVARs identified, there were 321 (1.12%) patients with ESRD on dialysis. Patients with ESRD had no difference in presenting AAA size (57.5 ± 12.7 mm vs 56.7 ± 17.2 mm; P = .44); however, they had more urgent/emergent repairs (20.6% vs 13.6%; P = .002) than those without ESRD. ESRD patients were more often younger, nonwhite, and nonobese and less likely to have commercial insurance (P < .05). ESRD patients more often had hypertension, coronary artery disease, congestive heart failure, previous lower extremity bypass, aneurysm repair, and carotid interventions (P < .05). There was no difference in the rate of concomitant procedures. Matching based on demographics, comorbidities, and operative details showed that ESRD patients had longer hospital length of stay (4.8 ± 9.4 days vs 4.1 ± 12.6 days; P = .026) and higher 30-day mortality (7% vs 2.4%; P < .001). There was no difference in cardiac, pulmonary, lower extremity, bowel, and stroke complications or return to the operating room. On multivariable analysis, ESRD was associated with 30-day mortality (odds ratio, 4.1; 95% confidence interval, 2.6-6.7; P < .001). Of the 24,750 elective EVARs, 1.04% had ESRD on dialysis. Matched data for elective EVAR show increased postoperative length of stay, hospital mortality, and 30-day mortality for ESRD patients on dialysis compared with those who are not. There was no association with postoperative myocardial infarction or pulmonary complications. At 1 year, patients with ESRD on dialysis had worse survival (78% vs 94%; P < .001), and ESRD was associated with higher mortality (hazard ratio, 3.3; 95% confidence interval, 2.5-4.2; P < .001).

CONCLUSIONS

Among patients undergoing EVAR, ESRD is independently associated with higher perioperative and 1-year mortality despite not being associated with higher postoperative complications. This should be taken into account during informed consent for EVAR and risk-benefit considerations in this high-risk population, particularly for elective repair.