Indications, risk factors, and outcomes of 30-day readmission after infrarenal abdominal aneurysm repair

Risk factors for readmission after open abdominal aortic aneurysms repair and its outcome in chronic kidney disease patients

OBJECTIVE

Readmission after vascular procedures is a burden to hospitals and the Medicare system. Therefore, identifying risk factors leading to readmission is vital. We examined the frequency of and risk factors for 30-day readmission after open aneurysm repair (OAR) and explored post-operative outcomes with special attention for those with preexisting chronic kidney disease (CKD).

METHODS

Patients who underwent OAR were identified in the National Readmission Database (2016-2018). Demographic information and comorbidities were collected. Patients readmitted within 30 days after their index hospitalization were identified and compared to patients without readmission records.

RESULTS

A total of 5090 patients underwent OAR during the study timeframe with 488 patients (9.6%) were readmitted within 30 days. Females were more readmitted than males (F = 11.1% vs M = 9.0%, P < 0.001). Readmitted patients had more comorbidities (median ECI 12, P < 0.05), were on Medicare (73.7%, P < 0.001), had higher surgery admission cost ($146,844, P < 0.001), longer length of stay (8 days, P < 0.001), and were discharged to a lower level care facility (62.7%, P < 0.001). Comorbidities that predisposed patients for readmission include: peripheral arterial disease (OR 2.15, P < 0.01), asthma (OR 1.87, P < 0.01), chronic heart failure (OR 1.74, P < 0.05). On readmission visit, acute renal failure (23.8%) was the most common diagnosis, while intestinal surgery (13.7%) was the most common procedure. Patients with CKD (n = 968, 18.9% of total population) had double the mortality rate compared to non-CKD patients on surgery admission (10.4%, P < 0.001) and readmission (10.1%, P < 0.001).

CONCLUSION

Certain factors were noted to increase readmission rate, special attention need to be paid when dealing with such group of patients requiring OAR. Vascular surgeons should meticulously weigh benefits and risks when considering OAR in patients with CKD who are not a candidate for endovascular repair, and optimize their kidney function before considering such approach.

Depression Is Associated With Non-Home Discharge After Coronary Artery Bypass Graft

INTRODUCTION

Depression is disproportionately high in patients with coronary artery disease and has been associated with adverse outcomes following coronary artery bypass graft (CABG). One quality metric, non-home discharge (NHD), can have substantial implications for patients and health care resource utilization. Depression increases the risk of NHD after many operations, but it has not been studied after CABG. We hypothesized that a history of depression would be associated with an increased risk of NHD following CABG.

METHODS

CABG cases were identified from the 2018 National Inpatient Sample using ICD-10 codes. Depression, demographic data, comorbidities, length of stay (LOS), rate of NHD were analyzed using appropriate statistical tests where a P-value < 0.05 was defined as statistically significant. Adjusted multivariable logistic regression models were used to assess independent association between depression and NHD as well as LOS while controlling for confounders.

RESULTS

There were 31,309 patients, of which 2743 (8.8%) had depression. Depressed patients were younger, females, in a lower income quartile, and more medically complex. They also demonstrated more frequent NHD and prolonged LOS. After adjusted multivariable analysis, depressed patients had a 70% increased odds of NHD (adjusted odds ratio: 1.70 [1.52-1.89] P < 0.001) and a 24% increased odds of prolonged LOS (AOR: 1.24 [1.12-1.38] P < 0.001).

CONCLUSIONS

From a national sample, depressed patients were associated with more frequent NHD following CABG. To our knowledge, this is the first study to demonstrate this, and it highlights the need for improved preoperative identification in order to improve risk stratification and timely allocation of discharge services.

Risk for surgical interventions following endovascular aneurysm repair with Endologix AFX or AFX2 Endovascular AAA Systems compared to other devices

OBJECTIVE

To evaluate the risk for 90-day returns to care and long-term subsequent surgical interventions following primary endovascular aneurysm repair (EVAR) with an Endologix AFX Endovascular AAA System compared to three other high-volume endograft devices.

METHODS

We conducted a matched cohort study using data from an integrated healthcare system's Endovascular Stent Graft Registry. Patients aged ≥18 years who underwent primary EVAR for AAA in the healthcare system from 1/1/2011-12/31/2017 comprised the eligible study sample. The treatment group included patients who received an Endologix AFX or AFX2 device (n=470). Patients who received one of three other high-volume endograft devices used within the healthcare system comprised the eligible comparison group (n=2122). These patients were 2:1 propensity score matched without replacement to patients who received an Endologix device based on a number of patient and procedure characteristics. After the application of matching, conditional logistic regression was used to evaluate the likelihood for 90-day emergency department (ED) visit and readmission. Cause-specific Cox regression was used to evaluate the long-term risk of endoleak, graft revision, secondary reintervention (not including revision), conversion to open repair, and rupture during follow-up. Cox proportional hazards regression was used to evaluate the risk of mortality (overall and aneurysm-related).

RESULTS

The final matched study sample included 470 patients who received an Endologix AFX or AFX2 device and 940 patients who received a different high-volume device. Compared to the other devices, AFX/AFX2 had a higher risk for type III endoleak (hazard ratio [HR]=38.79, 95% confidence interval [CI]=14.51-103.67), revision surgery more than 1-year following the primary EVAR (HR=4.50, 95% CI=3.10-6.54), rupture (HR=6.52, 95% CI=1.73-24.63), and aneurysm-related mortality (HR=2.43, 95% CI=1.32-4.47) was observed with use of AFX/AFX2.

CONCLUSION

In our matched cohort study, patients who received an Endologix AFX System during their primary EVAR had a higher risk for several adverse longitudinal outcomes, as well as aneurysm-related mortality, when compared to patients who received other high-volume devices. Patients who have received these devices should be closely monitored following EVAR.

Social Vulnerability And Outcomes For Access-Sensitive Surgical Conditions Among Medicare Beneficiaries

Concerns have been raised over wide variation in rates of unplanned (emergency or urgent) surgery for access-sensitive surgical conditions-diagnoses requiring surgery that preferably is planned (elective) but, when access is limited, may be delayed until worsening symptoms require riskier and costlier unplanned surgery. Yet little is known about geographic and community-level factors that may increase the likelihood of unplanned surgery with adverse outcomes. We examined the relationship between community-level social vulnerability and rates of unplanned surgery for three access-sensitive conditions in 2014-18 among fee-for-service Medicare beneficiaries ages 65-99. Compared with patients from communities with the lowest social vulnerability, those from communities with the highest vulnerability were more likely, overall, to undergo unplanned surgery (36.2 percent versus 33.5 percent). They were also more likely to experience worse outcomes largely attributable to differential rates of unplanned surgery, including higher rates of mortality (5.4 percent versus 5.0 percent) and additional surgery within thirty days (19.6 percent versus 18.1 percent). Our findings suggest that policy addressing community-level social vulnerability may mitigate the observed differences in surgical procedures and outcomes for access-sensitive conditions.

Impact of high-risk features and timing of repair for acute type B aortic dissections

OBJECTIVE

The new Society for Vascular Surgery/Society for Thoracic Surgery reporting standards for type B aortic dissection (TBAD) categorize clinical presentations of aortic dissection into uncomplicated, high-risk features (HRF), and complicated groups. Although it is accepted that complicated dissections require immediate repair, the optimal timing of repair for HRF has yet to be established. This study aims to identify the ideal timing of thoracic endovascular aortic repair (TEVAR) for HRF, as well as outcomes associated with specific HRF.

METHODS

The Vascular Quality Initiative was queried for TEVARs performed for acute and subacute TBAD with HRF from 2014 to 2020. Rupture, malperfusion, and uncomplicated patients were excluded. HRF were defined per the guidelines as refractory hypertension, pain, or rapid expansion/aneurysm of more than 40 mm. The primary outcomes were in-hospital/30-day mortality and 1-year survival with primary exposure variables being days from symptoms to repair and number of HRFs. Secondary outcomes were spinal cord ischemia, stroke, and retrograde type A dissection (RTAD).

RESULTS

Of the 1100 patients who met inclusion criteria, 811 had one HRF, 249 had two, and 40 had three. There were no significant differences in primary or secondary outcomes based on number of HRFs. There were 309 patients who underwent repair at 0 to 2 days, 262 at 3 to 6 days, 270 at 7 to 14 days, and 259 at 15 days or more. TEVAR performed at 15 days or more was independently associated with lower in-hospital/30-day mortality (odds ratio, 0.38; P = .0388) and improved 1-year survival. Postoperative stroke was associated with earlier repair (0-2 days). There was no association of timing of repair with spinal cord ischemia, retrograde type A dissection or reintervention.

CONCLUSIONS

TEVAR for TBAD with HRF delayed at least 15 days from symptom onset is associated with improved survival, supporting the theory that it is best to delay TEVAR until the subacute phase. Additionally, TEVAR delayed at least 3 days is associated with a decrease in stroke. Having more than one HRF was not associated statistically with worse outcomes. Because the classification of HRF is relatively new and without guidelines for repair, this study highlights the risks of early intervention for HRF and suggests that these patients seem to benefit from at least a short stabilization period before TEVAR.

Predictors of Rehospitalization and Mortality in Diabetes-Related Hospital Admissions

The risk factors of rehospitalization and death post-discharge in diabetes-related hospital admissions are not fully understood. To determine them, a population-based retrospective epidemiological survey was performed on diabetes-related admissions from the Polish national database. Logistic regression models were used, in which the dependent variables were rehospitalization due to diabetes complications and death within 90 days after the index hospitalization. In 2017, there were 74,248 hospitalizations related to diabetes. A total of 11.3% ended with readmission. Risk factors for rehospitalization were as follows: age < 35 years; male sex; prior hospitalization due to acute diabetic complications; weight loss; peripheral artery disease; iron deficiency anemia; kidney failure; alcohol abuse; heart failure; urgent, emergency, or weekend admission; length of hospitalization; and hospitalization in a teaching hospital with an endocrinology/diabetology unit. Furthermore, 7.3% of hospitalizations resulted in death within 90 days following discharge. Risk factors for death were as follows: age; neoplastic disease with/without metastases; weight loss; coagulopathy; alcohol abuse; acute diabetes complications; heart failure; kidney failure; iron deficiency anemia; peripheral artery disease; fluid, electrolytes, and acid–base balance disturbances; urgent or emergency and weekend admission; and length of hospitalization. We concluded that of all investigated factors, only hospitalization within an experienced specialist center may reduce the frequency of the assessed outcomes.

Influence of shape-memory stent grafts on local aortic compliance

The effect of repair techniques on the biomechanics of the aorta is poorly understood, resulting in significant levels of postoperative complications for patients worldwide. This study presents a computational analysis of the influence of Nitinol-based devices on the biomechanical performance of a healthy patient-specific human aorta. Simulations reveal that Nitinol stent-grafts stretch the artery wall so that collagen is stretched to a straightened high-stiffness configuration. The high-compliance regime (HCR) associated with low diastolic lumen pressure is eliminated, and the artery operates in a low-compliance regime (LCR) throughout the entire cardiac cycle. The slope of the lumen pressure–area curve for the LCR post-implantation is almost identical to that of the native vessel during systole. This negligible change from the native LCR slope occurs because the stent-graft increases its diameter from the crimped configuration during deployment so that it reaches a low-stiffness unloading plateau. The effective radial stiffness of the implant along this unloading plateau is negligible compared to the stiffness of the artery wall. Provided the Nitinol device unloads sufficiently during deployment to the unloading plateau, the degree of oversizing has a negligible effect on the pressure–area response of the vessel, as each device exerts approximately the same radial force, the slope of which is negligible compared to the LCR slope of the native artery. We show that 10% oversizing based on the observed diastolic diameter in the mid descending thoracic aorta results in a complete loss of contact between the device and the wall during systole, which could lead to an endoleak and stent migration. 20% oversizing reaches the Dacron enforced area limit (DEAL) during the pulse pressure and results in an effective zero-compliance in the later portion of systole.

Depression Predicts Non-Home Discharge After Abdominal Aortic Aneurysm Repair

BACKGROUND

Mental health's impact on vascular surgical patients has long been overlooked. While outside the expertise of most surgeons, understanding the role that depression plays in the postoperative course could provide additional insight into opportunities to improve surgical outcomes and healthcare value. Additionally, non-home discharge (NHD) to a rehabilitation or skilled nursing facility after surgery is associated with impaired quality of life and higher postdischarge complications, readmissions, and mortality. We hypothesized that depression would be associated with an increased risk for NHD following abdominal aortic aneurysm (AAA) repair.

METHODS

Nonruptured AAA repair cases were identified from the National Inpatient Sample (NIS) using ICD-9 codes between 2005 and 2014. Depression, comorbidities, postoperative complications, and discharge destination were evaluated using statistical tests as appropriate to the data. A hierarchical multivariable logistic regression controlling for hospital level variation was used to examine the independent association between depression, and the primary outcome of NHD controlling for median income and confounders meeting P < 0.05 on univariate analysis.

RESULTS

There were 99,934 total cases analyzed, of which 4,755 (4.8%) were diagnosed with depression and 10,618 (11.9%) required NHD. Patients with depression were younger, more likely to be women, white, have diabetes, chronic obstructive pulmonary disease, hypertension, tobacco use, and more likely to experience a postoperative complication. On adjusted multivariable analysis, patients with depression were more likely to require NHD (odds ratio [OR] 1.87, 95% confidence interval [CI]: 1.68-2.08, c-statistic = 0.82). On stratified analysis by operative approach, depression had a larger effect estimate in endovascular repair (OR 2.19; 95% CI: 1.90-2.52) versus open repair (OR 1.60; 95% CI: 1.38-1.87).

CONCLUSIONS

In a nationally representative sample, patients with depression were more likely to require NHD after AAA repair. This study highlights the importance that depression plays in postoperative outcomes after AAA repair. Furthermore, addressing mental health preoperatively has the potential to improve outcomes in patients undergoing AAA repair.

Patients with depression are less likely to go home after critical limb revascularization

BACKGROUND

Although often overlooked during the preoperative evaluation, recent evidence has suggested that depression in patients with peripheral artery disease is associated with increased postoperative complications, including decreased primary and secondary patency after revascularization and an increased risk of major amputation and mortality. Postoperative nonhome discharge (NHD) is an important outcome for patients and has also been associated with other adverse outcomes; however, the effect that depression has on NHD after vascular surgery has remained unexplored. We hypothesized that depression would be associated with an increased risk of NHD after revascularization for chronic limb threatening ischemia (CLTI).

METHODS

Endovascular, open, and hybrid (combined open and endovascular) cases of revascularization for CLTI were identified from the 2012 to 2014 National (Nationwide) Inpatient Sample. CLTI, diagnoses of depression, and medical comorbidities were defined using the corresponding International Classification of Diseases, Ninth Revision, Clinical Modification codes. A hierarchical multivariable binary logistic regression controlling for hospital level variation and for confounders meeting P <.01 on bivariate analysis was used to examine the association between depression and NHD. A sensitivity analysis after coarsened exact matching for baseline characteristics that differed between the two groups was performed to reduce any imbalance.

RESULTS

A total of 64,817 cases were identified, of which 5472 (8.4%) included a diagnosis of depression and 16,524 (25.5%) NHD. The patients with depression were younger and more likely to be women and white, have multiple comorbidities and a nonelective admission, and experience a postoperative complication (P <.05). On unadjusted analyses, patients with depression had an 8% absolute increased risk of requiring NHD (32.1% vs 24.9%; P <.001). On multivariable analysis, patients with depression had an increased odds for NHD (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.40-1.61; c-statistic, 0.81) compared with those without depression. After stratification by operative approach, depression had a larger effect estimate in endovascular revascularization (OR, 1.57; 95% CI, 1.42-1.74) compared with open (OR, 1.45; 95% CI, 1.30-1.62). A test for interaction between depression and gender identified that men with depression had greater odds of NHD compared with women with depression (OR, 1.68; 95% CI, 1.51-1.88; vs OR, 1.37; 95% CI, 1.25-1.51; interaction P <.01). A sensitivity analysis after coarsened exact matching confirmed these findings.

CONCLUSIONS

To the best of our knowledge, the present study is the first to identify an association between depression and NHD after revascularization for CLTI. These results provide further evidence of the negative effects that comorbid depression has on patients undergoing revascularization for CLTI. Future studies should examine whether treating depression can improve the outcomes in this patient population.

A novel preoperative risk score for nonhome discharge after elective thoracic endovascular aortic repair

BACKGROUND

Nonhome discharge (NHD) to a rehabilitation or skilled nursing facility after vascular surgery is poorly described despite its large impact on patients. Understanding postsurgical NHD risk is essential to providing adequate preoperative counseling and shared decision making, particularly for elective surgeries. We aimed to identify independent predictors of NHD after elective thoracic endovascular aortic repair (TEVAR) for thoracic aortic aneurysms (TAA) and to create a clinically useful preoperative risk score.

METHODS

Elective TEVAR cases for descending TAA were queried from the Society for Vascular Surgery Vascular Quality Initiative from 2014 to 2018. A risk score was created by splitting the dataset into two-thirds for model development and one-third for validation. A parsimonious stepwise hierarchical multivariable logistic regression controlling for hospital level variation was performed in the development dataset, and the beta-coefficients were used to assign points for a risk score. This score was then cross-validated and model performance assessed.

RESULTS

Overall, 1469 patients were included and 213 (14.5%) required NHD. At baseline, patients who required NHD were more likely to be ≥80 years old (35.2% vs 19.4%), female (58.7% vs 40.6%), functionally dependent (42.3% vs 24.0%), and anemic (46.5% vs 27.8%), and to have chronic obstructive pulmonary disease (41.3% vs 33.4%), congestive heart failure (18.8% vs 11.1%), and American Society of Anesthesiologists class ≥4 (51.6% vs 39.8%; all P < .05). Multivariable analysis in the development group identified independent predictors of NHD that were used to create an 18-point risk score. Patients were stratified into three groups based upon their risk score: low risk (0-7 points; n = 563) with an NHD rate of 4.3%, moderate risk (8-11 points; n = 701) with an NHD rate of 17.0%, and high risk (≥12 points; n = 205) with an NHD rate of 34.2%. The risk score had good predictive ability with a c-statistic of 0.75 for model development and a c-statistic of 0.72 in the validation dataset.

CONCLUSIONS

This novel risk score can predict NHD after TEVAR for TAA using characteristics that can be identified preoperatively. The use of this score may allow for improved risk assessment, preoperative counseling, and shared decision making.

Impact of patient factors and procedure on readmission after aortic dissection admission in the states of Florida and New York

BACKGROUND

Readmissions after aortic dissection (AD) admission are not well described. Using state-based administrative claims data, we sought to define readmission rates after AD and to identify factors associated with them.

METHODS

State Inpatient Databases for Florida (2007-2012) and New York (2008-2012) were queried for AD index admissions. Admissions were stratified by initial treatment strategy: type A open surgery repair (TAOR), type B open surgery repair (TBOR), thoracic endovascular aortic repair (TEVAR), or medical management (MM). All-cause readmission rates were calculated at 30 days, 90 days, and 2 years. Logistic regression was used to identify factors associated with readmission at each time point for all type A admissions (TAOR) or type B admissions (TBOR, TEVAR, MM).

RESULTS

We identified 4670 patients with an AD index admission. Treatment was with TAOR in 1031 (22%), TBOR in 761 (16%), TEVAR in 412 (9%), and MM in 2466 (53%). Patients were predominantly male (59.4%) and white (61.9%), with a median age of 66 years. Overall mortality during AD index admission was 14.8% (TAOR, 15.8%; TBOR, 17.1%; TEVAR, 9.0%; MM, 14.7%; P = .002 across all groups). All-cause readmission rates were similar across treatment groups at 30 days (9.6%-11%; P = .56), 90 days (15.2%-20%; P = .26), and 2 years (49.2%-54.4%; P = .15). Higher income quartile (vs lowest) was associated with lower odds of early readmission (at 30 days and 90 days) after type B admissions but not after type A admissions. At 2 years, self-pay (vs Medicare) was associated with lower odds of readmission in both type A and type B admissions, whereas higher comorbidity count and black race (vs white) were associated with higher odds of readmission. TEVAR (vs MM) was also associated with higher odds of readmission. Cardiovascular disease was the most common cause for readmission at all time points. Emergency department readmission counts were highest after MM admissions, and ambulatory surgical admissions were highest after TBOR. Both TEVAR and MM initial costs were lower than TAOR and TBOR costs, but at 2 years, costs remained significantly lower only for MM.

CONCLUSIONS

In-state 30-day, 90-day, and 2-year readmission rates after AD were not associated with initial treatment type. Two-year readmissions are common. Strategies to target socioeconomic, race, and geographic factors may reduce variations in readmission patterns after AD admission.

Frequency of 30-Day Readmission and Its Causes After Endovascular Aneurysm Intervention of Abdominal Aortic Aneurysm (from the Nationwide Readmission Database)

Endovascular aneurysm intervention (EVAI) is one of the most commonly performed vascular interventions for abdominal aortic aneurysm (AAA). Data regarding 30-day readmission rates after EVAI are poorly reported in the literature. We used the United States Nationwide Readmission Database from 2010 to 2014 to identify all patients ≥18 years who were readmitted within 30 days after a hospital discharge for EVAI of the AAA. Incidence, etiologies, predictors of 30-day readmission, and trends of readmission rates were analyzed. In 138,014 patients who survived to discharge after an EVAI procedure for AAA, 14,146 (10.24%) were readmitted within 30 days. Median time to readmission was 11 days. Cardiac causes (16.34%) followed by infections (15.40%) and vascular complications (12.86%) were common etiologies of readmission. Greater patient age, female sex, coexisting co-morbidities such as heart failure, atrial fibrillation, peripheral vascular disease, lung disease, and chronic kidney disease were independent predictors of 30-day readmission. In-hospital complications during an index admission such as major bleeding or vascular complications were also predictive of 30-day readmission. Trend analysis showed a progressive decline in readmission rates from 11.3% in 2010 to 9.6% in 2014 (p_trend <0.0001), 20% lower odds in 2014 compared with 2010 (odds ratio 0.80, 95% confidence interval 0.72 to 0.87, p <0.0001). In this contemporary study of EVAI for AAA, nearly 1 in 10 patients was readmitted within 30 days of discharge after an index admission. Cardiac complications and infections were common causes of readmission within 30 days.

Predictors of in-hospital adverse events after endovascular aortic aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) offered outstanding survival benefit but at the expense of cost, periodic radiographic monitoring, and higher reinterventions rates. Perioperative complications, although rare, can occur after EVAR, contributing to longer hospitalization, higher cost, and significant comorbidity and mortality. Therefore, the aim of this study was to identify the predictors of in-hospital events (IHEs) after elective EVAR.

METHODS

The Vascular Quality Initiative database was explored from 2003 to 2017. Patients who had converted to open repair were excluded. IHEs were defined as any in-hospital myocardial infarction, dysrhythmia, congestive heart failure (CHF), stroke, pneumonia, respiratory failure, renal failure, lower extremity ischemia, bowel ischemia, or reoperation. Stepwise backward selection based on the Akaike information criterion statistic was implemented to select the predictors of IHE from the multivariable logistic regression models. Bootstrapping was performed with 1000 replications to internally validate the model and to obtain bias-corrected estimates. Receiver operating characteristic curves (area under the curve [AUC]) and Hosmer-Lemeshow tests were used to assess the discrimination and calibration of the models.

RESULTS

A total of 28,240 patients with full information about IHEs were included. Any IHE took place in 2365 (8.4%) patients. Patients who had an IHE were slightly older (mean age ± standard deviation, 75.6 ± 8.1 years vs 73.3 ± 8.5 years; P < .001]. A higher proportion of women had an IHE (25.6% vs 17.9%; P < .001). Comorbid conditions were more prevalent in patients who developed an IHE (chronic kidney disease, 49.1% vs 33.2%; coronary artery disease, 34.3% vs 29.0%; moderate to severe CHF, 3.9% vs 1.4%; chronic obstructive pulmonary disease, 42.5% vs 31.9%; hypertension, 87.0% vs 83.1%; and diabetes, 18.0% vs 16.1%; all P ≤ .015). An IHE was associated with high in-hospital (5.6% vs 0.03%) and 30-day mortality (6.3% vs 0.3%; both P < .001) and worse 3-year survival beyond the perioperative period (81.1% [79.3%-82.9%] vs 91.1% [90.7%-91.5%]; P < .001). Two models were constructed, one from preoperative factors and the second from preoperative and intraoperative factors. The selected predictors of IHEs were female sex, moderate or severe CHF, chronic kidney disease, coronary artery disease, chronic obstructive pulmonary disease, hypertension, and aneurysm diameter. Intraoperative factors were contrast material volume, operative time, and packed red blood cell transfusion. Nomograms were constructed from the final models. AUC significantly improved after adding intraoperative factors (AUC [95% confidence interval], 0.71 [0.70-0.73] vs 0.65 [0.64-0.66]; P < .001].

CONCLUSIONS

In-hospital adverse events can complicate the perioperative course of EVAR and increase the risk of operative and long-term mortality. Predicting IHEs and identifying their risk factors can potentially mitigate their development in patients at high risk. Predicting IHE risk can have tremendous prognostic value and help disposition planning. This study introduces an internally validated tool to enable vascular surgeons to identify patients' chance of having an IHE.

A Unique All-Payer Rate-Setting System Controls the Cost but Not the Racial Disparity in Lower Extremity Revascularization Procedures

BACKGROUND

Patients with peripheral arterial disease often have high comorbidity burden that may complicate post-interventional course and drive increased health-care expenditures. Racial disparity had been observed in lower extremity revascularization (LER) patterns and outcomes. In 2014, Maryland adopted an all-payer rate-setting system to limit the rising hospitalization costs. This resulted in an aggregate payment system in which hospital compensation takes place as an overall per capita expenditure for hospital services. We sought to examine racial differences and other patient-level factors that might lead to discrepancies in LER hospital costs in the State of Maryland.

METHODS

We used International Classification of Diseases, Ninth Revision codes to identify patients who underwent infrainguinal open bypass (open) and endovascular repair (endo) in the Maryland Health Services Cost Review Commission database (2009-2015). Multivariable generalized linear model regression analysis was conducted to report cost differences adjusting for patient-specific demographics, comorbidities, and insurance status. Logistic regression analysis was used to assess quality metrics: intensive care unit (ICU) admission, 30-day readmission, protracted length of stay (pLOS) (endo: pLOS >9, open: pLOS > 10 days) and in-hospital mortality.

RESULTS

Among patients undergoing open, costs were higher for nonwhite patients (African-American [AA]: $6,092 [4,682-7,501], other: $3,324 [437-6,212]; both P ≤ 0.024), diabetics ($2,058 [837-3,279]; P < 0.001), and patients with Medicaid had an increased cost over Medicare patients by $4,325 (1,441-7,209). Critical limb ischemia (CLI) was associated with $5,254 (4,014-6,495) risk-adjusted cost increment. In addition, AA patients demonstrated higher risk-adjusted odds of ICU admission (adjusted odds ratio [aOR] [95% confidence interval {CI}]:1.65 [1.46-1.86]; P < 0.001) and pLOS (aOR [95% CI]: 1.56 [1.37-1.79]; P < 0.001) than their white counterparts. For patients undergoing endo, costs were higher for nonwhite patients (AA: $2,642 [1,574-3,711], other: $4,124 [2,091-6,157]; both P < 0.001). Patients with CLI and heart failure had increased costs after endo. AA patients were more likely to be readmitted or stayed longer after endo (1.16 [1.03-1.29], 1.34 [1.21-1.49]; both P < 0.010, respectively). The overall cost trend was rapidly increasing before all-payer rate policy implementation but it dramatically plateaued after 2014.

CONCLUSIONS

This study showed that the all-payer rate-setting system has curbed the LER rising costs, but these costs remained disproportionally higher for disadvantaged populations such as AA and Medicaid communities. This underpins the existing racial disparity in LER. AA patients had higher LER costs, most likely driven by extended hospitalization and ICU admission. Efforts could be directed to evaluate the contributing socioeconomic factors, invest in primary prevention of comorbid conditions that had shown to be associated with prohibitive costs, and identify mechanisms to overcome the existing racial disparity in LER within the promising cost-saving payment system at the State of Maryland.