Variability in utilization of drug eluting stents in United States: Insights from nationwide inpatient sample.

OBJECTIVES: We studied the trends and predictors of drug eluting stent (DES) utilization from 2006 to 2011 to further expound the inter-hospital variability in their utilization. BACKGROUND: We queried the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) between 2006 and 2011 using ICD-9-CM procedure code, 36.06 (bare metal stent) or 36.07 (drug eluting stents) for Percutaneous Coronary Intervention (PCI). Annual hospital volume was calculated using unique identification numbers and divided into quartiles for analysis. METHODS AND RESULTS: We built a hierarchical two level model adjusted for multiple confounding factors, with hospital ID incorporated as random effects in the model. About 665,804 procedures (weighted n = 3,277,884) were analyzed. Safety concerns arising in 2006 reduced utilization DES from 90% of all PCIs performed in 2006 to a nadir of 69% in 2008 followed by increase (76% of all stents in 2009) and plateau (75% in 2011). Significant between-hospital variation was noted in DES utilization irrespective of patient or hospital characteristics. Independent patient level predictors of DES were (OR, 95% CI, P-value) age (0.99, 0.98-0.99, <0.001), female(1.12, 1.09-1.15, <0.001), acute myocardial infarction(0.75, 0.71-0.79, <0.001), shock (0.53, 0.49-0.58, <0.001), Charlson Co-morbidity index (0.81,0.77-0.86, <0.001), private insurance/HMO (1.27, 1.20-1.34, <0.001), and elective admission (1.16, 1.05-1.29, <0.001). Highest quartile hospital (1.64, 1.25-2.16, <0.001) volume was associated with higher DES placement. CONCLUSION: There is significant between-hospital variation in DES utilization and a higher annual hospital volume is associated with higher utilization rate of DES. © 2015 Wiley Periodicals, Inc.

Impact of Hospital Volume on Outcomes of Lower Extremity Endovascular Interventions (Insights from the Nationwide Inpatient Sample [2006 to 2011]).

Our primary objective was to study postprocedural outcomes and hospitalization costs after peripheral endovascular interventions and the multivariate predictors affecting the outcomes with emphasis on hospital volume. The study cohort was derived from Healthcare Cost and Utilization Project Nationwide Inpatient Sample database (2006 to 2011). Peripheral endovascular interventions were identified using appropriate International Classification of Diseases, Ninth Revision diagnostic and procedural codes. Annual institutional volumes were calculated using unique identification numbers and then divided into quartiles. Two-level hierarchical multivariate mixed models were created. The primary outcome was inhospital mortality; secondary outcome was a composite of inhospital mortality and postprocedural complications. Amputation rates and hospitalization costs were also assessed. Multivariate analysis (odds ratio, 95% confidence interval, p value) revealed age (1.46, 1.37 to 1.55, p <0.001), female gender (1.28, 1.12 to 1.46, p <0.001), baseline co-morbidity status as depicted by a greater Charlson co-morbidity index score (≥2: 4.32, 3.45 to 5.40, p <0.001), emergent or urgent admissions(2.48, 2.14 to 2.88, p <0.001), and weekend admissions (1.53, 1.26 to 1.86, p <0.001) to be significant predictors of primary outcome. An increasing hospital volume quartile was independently predictive of improved primary (0.65, 0.52 to 0.82, p <0.001 for the fourth quartile) and secondary (0.85, 0.73 to 0.97, 0.02 for the fourth quartile) outcomes and lower amputation rates (0.52, 0.45 to 0.61, p <0.001). A significant reduction hospitalization costs ($-3,889, -5,318 to -2,459, p <0.001) was also seen in high volume centers. In conclusion, a greater hospital procedural volume is associated with superior outcomes after peripheral endovascular interventions in terms of inhospital mortality, complications, and hospitalization costs.

Effect of Hospital Volume on Outcomes of Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve implantation (TAVI) is associated with a significant learning curve. There is paucity of data regarding the effect of hospital volume on outcomes after TAVI. This is a cross-sectional study based on Healthcare Cost and Utilization Project's Nationwide Inpatient Sample database of 2012. Subjects were identified by International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes, 35.05 (Trans-femoral/Trans-aortic Replacement of Aortic Valve) and 35.06 (Trans-apical Replacement of Aortic Valve). Annual hospital TAVI volumes were calculated using unique identification numbers and then divided into quartiles. Multivariate logistic regression models were created. The primary outcome was inhospital mortality; secondary outcome was a composite of inhospital mortality and periprocedural complications. Length of stay (LOS) and cost of hospitalization were assessed. The study included 1,481 TAVIs (weighted n = 7,405). Overall inhospital mortality rate was 5.1%, postprocedural complication rate was 43.4%, median LOS was 6 days, and median cost of hospitalization was $51,975. Inhospital mortality rates decreased with increasing hospital TAVI volume with a rate of 6.4% for lowest volume hospitals (first quartile), 5.9% (second quartile), 5.2% (third quartile), and 2.8% for the highest volume TAVI hospitals (fourth quartile). Complication rates were significantly higher in hospitals with the lowest volume quartile (48.5%) compared to hospitals in the second (44.2%), third (39.7%), and fourth (41.5%) quartiles (p <0.001). Increasing hospital volume was independently predictive of shorter LOS and lower hospitalization costs. In conclusion, higher annual hospital volumes are significantly predictive of reduced postprocedural mortality, complications, shorter LOS, and lower hospitalization costs after TAVI.

Comparison of Inhospital Outcomes and Hospitalization Costs of Peripheral Angioplasty and Endovascular Stenting.

The comparative data for angioplasty and stenting for treatment of peripheral arterial disease are largely limited to technical factors such as patency rates with sparse data on clinical outcomes like mortality, postprocedural complications, and amputation. The study cohort was derived from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database from 2006 to 2011. Peripheral endovascular interventions were identified using appropriate International Classification of Diseases, Ninth Revision (ICD-9) Diagnostic and procedural codes. Two-level hierarchical multivariate mixed models were created. The primary outcome includes inhospital mortality, and secondary outcome was a composite of inhospital mortality and postprocedural complications. Amputation was a separate outcome. Hospitalization costs were also assessed. Endovascular stenting (odds ratio, 95% confidence interval, p value) was independently predictive of lower composite end point of inhospital mortality and postprocedural complications compared with angioplasty alone (0.96, 0.91 to 0.99, 0.025) and lower amputation rates (0.56, 0.53 to 0.60, <0.001) with no significant difference in terms of inhospital mortality alone. Multivariate analysis also revealed stenting to be predictive of higher hospitalization costs ($1,516, 95% confidence interval 1,082 to 1,950, p <0.001) compared with angioplasty. In conclusion, endovascular stenting is associated with a lower rate of postprocedural complications, lower amputation rates, and only minimal increase in hospitalization costs compared with angioplasty alone.

Trends of Hospitalizations in the United States from 2000 to 2012 of Patients >60 Years With Aortic Valve Disease.

In recent years, there has been an increased emphasis on the diagnosis and treatment of valvular heart disease and, in particular, aortic stenosis. This has been driven in part by the development of innovative therapeutic options and by an aging patient population. We hypothesized an increase in the number of hospitalizations and the economic burden associated with aortic valve disease (AVD). Using Nationwide Inpatient Sample from 2000 to 2012, AVD-related hospitalizations were identified using International Classification of Diseases, Ninth Revision, Clinical Modification, code 424.1, as the principal discharge diagnosis. Overall AVD hospitalizations increased by 59% from 2000 to 2012. This increase was most significant in patients >80 years and those with higher burden of co-morbidities. The most frequent coexisting conditions were hypertension, heart failure, renal failure, anemia, and diabetes. Overall inhospital mortality of patients hospitalized for AVD was 3.8%, which significantly decreased from 4.5% in 2000 to 3.5% in 2012 (p <0.001). The largest decrease in mortality was seen in the subgroup of patients who had heart failure (62% reduction), higher burden of co-morbidities (58% reduction), and who were >80 years (53% reduction). There was a substantial increase in the cost of hospitalization in the last decade from $31,909 to $38,172 (p <0.001). The total annual cost for AVD hospitalization in the United States increased from $1.3 billion in 2001 to $2.1 billion in 2011 and is expected to increase to nearly 3 billion by 2020. The last decade has witnessed a significant increase in hospitalizations for AVD in the United States. The associated decrease in inhospital mortality and increase in the cost of hospitalization have considerably increased the economic burden on the public health system.

Comparison of inhospital mortality, length of hospitalization, costs, and vascular complications of percutaneous coronary interventions guided by ultrasound versus angiography.

Despite the valuable role of intravascular ultrasound (IVUS) guidance in percutaneous coronary interventions (PCIs), its impact on clinical outcomes remains debatable. The aim of the present study was to compare the outcomes of PCIs guided by IVUS versus angiography in the contemporary era on inhospital outcomes in an unrestricted large, nationwide patient population. Data were obtained from the Nationwide Inpatient Sample from 2008 to 2011. Hierarchical mixed-effects logistic regression models were used for categorical dependent variables like inhospital mortality, and hierarchical mixed-effects linear regression models were used for continuous dependent variables like length of hospital stay and cost of hospitalization. A total of 401,571 PCIs were identified, of which 377,096 were angiography guided and 24,475 (weighted n = 119,102) used IVUS. In a multivariate model, significant predictors of higher mortality were increasing age, female gender, higher baseline co-morbidity burden, presence of acute myocardial infarction, shock, weekend and emergent admission, or occurrence of any complication during hospitalization. Significant predictors of reduced mortality were the use of IVUS guidance (odds ratio 0.65, 95% confidence interval 0.52 to 0.83; p <0.001) for PCI and higher hospital volumes (third and fourth quartiles). The use of IVUS was also associated with reduced inhospital mortality in subgroup of patients with acute myocardial infarction and/or shock and those with a higher co-morbidity burden (Charlson's co-morbidity index ≥2). In one of the largest studies on IVUS-guided PCIs in the drug-eluting stent era, we demonstrate that IVUS guidance is associated with reduced inhospital mortality, similar length of hospital stay, and increased cost of care and vascular complications compared with conventional angiography-guided PCIs.

Comparison of outcomes of balloon aortic valvuloplasty plus percutaneous coronary intervention versus percutaneous aortic balloon valvuloplasty alone during the same hospitalization in the United States.

The use of percutaneous aortic balloon balvotomy (PABV) in high surgical risk patients has resurged because of development of less invasive endovascular therapies. We compared outcomes of concomitant PABV and percutaneous coronary intervention (PCI) with PABV alone during same hospitalization using nation's largest hospitalization database. We identified patients and determined time trends using the International Classification of Diseases, Ninth Revision, Clinical Modification, procedure code for valvulotomy from Nationwide Inpatient Sample database 1998 to 2010. Only patients >60 years with aortic stenosis were included. Primary outcome included in-hospital mortality, and secondary outcomes included procedural complications, length of stay (LOS), and cost of hospitalization. Total 2,127 PABV procedures were identified, with 247 in PABV + PCI group and 1,880 in the PABV group. Utilization rate of concomitant PABV + PCI during same hospitalization increased by 225% from 5.1% in 1998 to 1999 to 16.6% in 2009 to 2010 (p <0.001). Overall in-hospital mortality rate and complication rates in PABV + PCI group were similar to that of PABV group (10.3% vs 10.5% and 23.4% vs 24.7%, respectively). PABV + PCI group had similar LOS but higher hospitalization cost (median [interquartile range] $30,089 [$21,925 to $48,267] versus $18,421 [$11,482 to $32,215], p <0.001) in comparison with the PABV group. Unstable condition, occurrence of any complication, and weekend admission were the main predictors of increased LOS and cost of hospital admission. Concomitant PCI and PABV during the same hospitalization are not associated with change in in-hospital mortality, complications rate, or LOS compared with PABV alone; however, it increases the cost of hospitalization.

Influence of hospital volume on outcomes of percutaneous atrial septal defect and patent foramen ovale closure: a 10-years US perspective.

BACKGROUND: Contemporary data regarding percutaneous closure of atrial septal defect/patent foramen ovale (ASD/PFO) are lacking. We evaluated the current trends in utilization of ASD/PFO closure in adults and investigated the effect of annual hospital volume on in-hospital outcomes. METHODS: We queried the Nationwide Inpatient Sample between the years 2001 and 2010 using the International Classification of Diseases (ICD-9-CM) procedure code for percutaneous closure of ASD/PFO with device. Hierarchical mixed effects models were generated to identify the independent multivariate predictors of outcomes. RESULTS: A total of 7,107 percutaneous ASD/PFO closure procedures (weighted n = 34,992) were available for analysis. A 4.7-fold increase in the utilization of this procedure from 3/million in 2001 to 14/million adults in 2010 in US (P < 0.001) was noted. Overall, percutaneous ASD/PFO closure was associated with 0.5% mortality and 12% in-hospital complications. The utilization of intracardiac echocardiography (ICE) increased 15 fold (P < 0.001) during the study period. The procedures performed at the high volume hospitals [2nd (14-37 procedures/year) and 3rd (>38 procedures/year) tertile] were associated with significant reduction in complications, length of stay and cost of hospitalization when compared to those performed at lowest volume centers (<13 procedures/year). Majority (70.5%) of the studied hospitals were found to be performing <10 procedures/year hence deviating from the ACC/AHA/SCAI clinical competency guidelines. CONCLUSIONS: Low hospital volume is associated with an increased composite (mortality and procedural complications) adverse outcome following ASD/PFO closure. In the interest of patient safety, implementation of the current guidelines for minimum required annual hospital volume to improve clinical outcomes is warranted.