Comparing hospital performance within and across countries: an illustrative study of coronary artery bypass graft surgery in England and Spain

Spillover effects and other determinants of medical device uptake in the presence of a medical guideline: An analysis of drug-eluting stents in Germany and Italy

We investigated the role of spillover effects among hospitals in the diffusion of drug-eluting stents (DES) in Germany and Italy during a period in which the relevant medical guideline clearly recommended their use over bare-metal stents. We used administrative data of hospitalized patients treated with ST-elevation myocardial infarction from 2012 to 2016 to estimate spatial panel models allowing for global spillover effects. We used an inverse-distance weights matrix to capture the geographical proximity between neighboring hospitals and assigned a lower weight to more distant neighbors. For both countries, we found significant positive spatial autocorrelation in most years based on the global Moran's I test, and a significant, positive spatial lag parameter across model specifications, indicating positive spillover effects among neighboring hospitals. We found that private for-profit hospital ownership and hospital competition in Germany and the number of inpatient cases with circulatory system diseases in Italy were other significant determinants of DES adoption. Our results underline the importance of spillover effects among peers for the diffusion of medical devices even in the presence of a positive guideline recommendation. Policymakers might therefore consider promoting various forms of exchange and collaboration among medical staff and hospitals to ensure the appropriate use of medical technologies.

Institutional variation in early mortality following isolated coronary artery bypass graft surgery

BACKGROUND

Thirty-day mortality following coronary artery bypass grafting (CABG) is a widely accepted marker for quality of care. Although surgical mortality has declined, the utility of this measure to profile quality has not been questioned. We assessed the institutional variation in risk-standardised mortality rates (RSMR) following isolated CABG within Australia and New Zealand (ANZ).

METHODS

We used an administrative dataset from all public and most private hospitals across ANZ to capture all isolated CABG procedures recorded between 2010 and 2015. The primary outcome was all-cause death occurring in-hospital or within 30-days of discharge. Hospital-specific RSMRs and 95% CI were estimated using a hierarchical generalised linear model accounting for differences in patient characteristics.

RESULTS

Overall, 60,953 patients (mean age 66.1 ± 10.1y, 18.7% female) underwent an isolated CABG across 47 hospitals. The observed early mortality rate was 1.69% (n = 1029) with 81.8% of deaths recorded in-hospital. The risk-adjustment model was developed with good discrimination (C-statistic = 0.81). Following risk-adjustment, a 3.9-fold variation was observed in RSMRs among hospitals (median:1.72%, range:0.84-3.29%). Four hospitals had RSMRs significantly higher than average, and one hospital had RSMR lower than average. When in-hospital mortality alone was considered, the median in-hospital RSMR was 1.40% with a 5.6-fold variation across institutions (range:0.57-3.19%).

CONCLUSIONS

Average mortality following isolated CABG is low across ANZ. Nevertheless, in-hospital and 30-day mortality vary among hospitals, highlighting potential disparities in care quality and the enduring usefulness of 30-day mortality as an outcome measure. Clinical and policy intervention, including participating in clinical quality registries, are needed to standardise CABG care.

Mortality risk prediction in high-risk patients undergoing coronary artery bypass grafting: Are traditional risk scores accurate?

Background

The performance of traditional scores is significantly limited to predict mortality in high-risk cardiac surgery. The aim of this study was to compare the performance of STS, ESII and HiriSCORE models in predicting mortality in high-risk patients undergoing CABG.

Methods

Cross-sectional analysis in the international prospective database of high-risk patients: HiriSCORE project. We evaluated 248 patients with STS or ESII (5–10%) undergoing CABG in 8 hospitals in Brazil and China. The main outcome was mortality, defined as all deaths occurred during the hospitalization in which the operation was performed, even after 30 days. Five variables were selected as predictors of mortality in this cohort of patients. The model’s performance was evaluated through the calibration-in-the-large and the receiver operating curve (ROC) tests.

Results

The mean age was 69.90±9.45, with 52.02% being female, 25% of the patients were on New York Heart Association (NYHA) class IV and 49.6% had Canadian Cardiovascular Society (CCS) class 4 angina, and 85.5% had urgency or emergency status. The mortality observed in the sample was 13.31%. The HiriSCORE model showed better calibration (15.0%) compared to ESII (6.6%) and the STS model (2.0%). In the ROC curve, the HiriSCORE model showed better accuracy (ROC = 0.74) than the traditional models STS (ROC = 0.67) and ESII (ROC = 0.50).

Conclusion

Traditional models were inadequate to predict mortality of high-risk patients undergoing CABG. However, the HiriSCORE model was simple and accurate to predict mortality in high-risk patients.

Retrospective cohort analysis of Spanish national trends of coronary artery bypass grafting and percutaneous coronary intervention from 1998 to 2017

INTRODUCTION

Spain is one of the countries with the lowest rates of revascularisation and highest ratio of percutaneous coronary intervention (PCI) to coronary artery bypass grafting (CABG).

OBJECTIVES

To investigate the changes and trends in the two revascularisation procedures between 1998 and 2017 in Spain.

DESIGN

Retrospective cohort study. Analysis of in-hospital outcomes.

SETTING

Minimum basic data set from the Spanish National Department of Health: mandatory database collecting information of patients who are attended in the Spanish public National Health System.

PARTICIPANTS

603 976 patients who underwent isolated CABG or PCI in the Spanish National Health System. The study period was divided in four 5-year intervals. Patients with acute myocardial infarction on admission were excluded.

PRIMARY AND SECONDARY OUTCOMES

We investigated the volume of procedures nationwide, the changes of the risk profile of patients and in-hospital mortality of both techniques.

RESULTS

We observed a 2.2-fold increase in the rate of any type of myocardial revascularisation per million inhabitants-year: 357 (1998) to 776 (2017). 93 682 (15.5%) had a coronary surgery. PCI to CABG ratio rose from 2.2 (1998-2002) to 8.1 (2013-2017). Charlson's index increased by 0.8 for CABG and 1 for PCI. The median annual volume of PCI/hospital augmented from 136 to 232, while the volume of CABG was reduced from 137 to 74. In the two decades, we detected a significant reduction of CABG in-hospital mortality (6.5% vs 2.6%, p<0.001) and a small increase in PCI (1.2% vs 1.5%, p<0.001). Risk adjusted mortality rate was reduced for both CABG (1.51 vs 0.48, p<0.001), and PCI (1.42 vs 1.05, p<0.001).

CONCLUSION

We detected a significant increase in the volume of revascularisations (particularly PCI) in Spain. Risk-adjusted in-hospital mortality was significantly reduced.

Off-pump versus on-pump coronary artery surgery in octogenarians (from the KROK Registry)

Background

According to the medical literature, both on-pump and off-pump coronary artery surgery is safe and effective in octogenarians.

Objectives

The aim of our study was to examine the epidemiology, in-hospital outcomes and long-term follow-up results in octogenarians undergoing off-pump and on-pump coronary artery surgery utilizing nationwide registry data.

Methods

All octogenarians (≥ 80 years) enrolled in the Polish National Registry of Cardiac Surgical Procedures (KROK Registry), who underwent isolated coronary surgery between January 2006 and September 2017 were identified. Preoperative data, perioperative complications, hospital mortality and long-term mortality were analyzed. Unadjusted and propensity-matched comparisons were performed between octogenarians undergoing off-pump and on-pump coronary artery bypass surgery.

Results

Octogenarians accounted for 4.1% of the total population undergoing coronary artery surgery in Poland during the analyzed period (n = 152,631) and this percentage is increasing. Among 6,006 analyzed patients, 2,744 (45.7%) were operated on-pump and 3,262 (54.3%) were operated off-pump. Propensity-matched analysis revealed that patients operated on-pump were more often reoperated due to postoperative bleeding and their in-hospital mortality was higher (6.6% vs 4.5%, p = 0.006 and 8.7% vs 5.8%, p = 0.001, respectively). Long-term all-cause mortality was lower among patients operated off-pump (p = 0.013).

Conclusion

On the basis of our findings we suggest that off pump technique should be considered as perfectly acceptable in octogenarians.

Isolated aortic valve replacement in Spain: national trends in risks, valve types, and mortality from 1998 to 2017

INTRODUCTION AND OBJECTIVES

To help to illustrate the trends in isolated surgical aortic valve replacement (SAVR) in Spain, we performed a national-level analysis to investigate the changes from 1998 to 2017 in a) SAVR volume, b) patients' risk profiles, c) in-hospital mortality, and d) types of aortic valve prostheses.

METHODS

We included all episodes of patients undergoing isolated SAVR from January 1998 to December 2017 recorded in the Minimum Basic Data Set (Ministry of Health, Consumer Affairs, and Social Welfare, Spain). The study duration was divided into four 5-year periods. We analyzed the trends in SAVR volume, comorbidity prevalence, and in-hospital mortality. Through multivariate logistic regression, we identified factors associated with mortality and type of prosthesis. The risk-adjusted mortality rate was compared over the study period.

RESULTS

In total, 73 668 patients underwent an isolated SAVR from 1998 to 2017. The annual volume of procedures increased from 16 363 between 1998 and 2002 to 22 685 between 2013 and 2017. The prevalence of all investigated comorbidities increased, except for history of previous myocardial infarction and unplanned admission. The Charlson comorbidity index worsened from 1998-2002 (2.3; SD, 1.4) to 2013-2017 (3.6; SD, 1.7) (P <.001). In-hospital mortality decreased from 7.2% to 3.3% (P <.001) while the risk-adjusted mortality index improved from 1.3 to 0.7. The proportion of bioprostheses increased from 20.7% (1998-2002) to 59.6% (2013-2017) (P <.001).

CONCLUSIONS

We detected an increase in the annual SAVR volume in Spain, with more patients receiving bioprostheses. Despite an increased risk profile of the patients, in-hospital mortality substantially reduced.

Coronary artery bypass grafting in Spain. Influence of procedural volume on outcomes

INTRODUCTION AND OBJECTIVES

To analyze the association between volume and outcomes in coronary artery bypass grafting (CABG) in the Spanish National Health System.

METHODS

We analyzed CABG episodes from 2013 to 2015. The selected outcome variables were in-hospital mortality in the index episode, 30-day cardiac-related readmissions, and mortality during readmission. Risk-adjusted rates of in-hospital mortality (RAMR) and 30-day readmissions (RARR) were calculated using multilevel logistic regression. High- and low-volume hospitals for CABG were identified by a nonconditioned analysis (k-means) and by compliance with the volume recommendation of clinical practice guidelines.

RESULTS

A total of 17 335 CABG index episodes were included, with a crude in-hospital mortality rate of 5.0%. Episodes attended in low-volume centers for CABG (< 155 CABG per year) showed 17% higher RAMR (5.81%±2.07% vs 4.96%±1.76%; P <.001) and a negative linear correlation between volume and RARR (r=-0.318; P=.029), as well as a higher percentage of complications during the episode. The same association between volume and more favorable outcomes was found in isolated CABG.

CONCLUSIONS

The mean CABG volume is low in Spanish National Health System hospitals. Higher volume was associated with better outcomes in CABG, both total and isolated. The findings of this study indicate the need for a higher concentration of CABG programs, as well as the publication of risk-adjusted outcomes of coronary intervention.

Exploring the role of hospitals and office-based physicians in timely provision of statins following acute myocardial infarction: a secondary analysis of a nationwide cohort using cross-classified multilevel models

OBJECTIVES

To examine the role of hospitals and office-based physicians in empirical networks that deliver care to the same population with regard to the timely provision of appropriate care after hospital discharge.

DESIGN

Secondary data analysis of a nationwide cohort using cross-classified multilevel models.

SETTING

Transition from hospital to ambulatory care.

PARTICIPANTS

All patients discharged for acute myocardial infarction (AMI) from Germany's largest statutory health insurance fund group in 2011.

MAIN OUTCOME MEASURE

Patients' odds of receiving a statin prescription within 30 days after hospital discharge.

RESULTS

We found significant variation in 30-day statin prescribing between hospitals (median OR (MOR) 1.40; 95% credible interval (CrI) 1.36 to 1.45), hospital-physician pairs caring for the same patients (MOR 1.32; 95% CrI 1.26 to 1.38) and to a lesser extent between physicians (MOR 1.14; 95% CrI 1.11 to 1.19). About 67% of the variance between hospital-physician pairs and about 45% of the variance between hospitals was explained by hospital characteristics including a rural location, teaching status and the number of beds, the number of patients shared between a hospital and an office-based physician as well as 16 patient characteristics, including multimorbidity and dementia. We found no impact of physician characteristics.

CONCLUSIONS

Timely prescription of appropriate secondary prevention pharmacotherapy after AMI is subject to considerable practice variation which is not consistent with clinical guidelines. Hospitals contribute more to the observed variation than physicians, and most of the variation lies at the patient level. To ensure care continuity for patients, it is important to strengthen hospital capacity for discharge management and coordination between hospitals and office-based physicians.

Percutaneous cardiological intervention and cardiac surgery: patient-centered care. Position statement of the Spanish Society of Cardiology

The percutaneous treatment of coronary artery disease and some structural cardiovascular diseases has undergone spectacular changes. More and more patients with different types of heart disease are being treated by percutaneous or transcatheter interventions, with no such increase in patients undergoing cardiac surgery. This situation has led to different types of approach, requiring an objective analysis that includes all the factors possibly influencing these changes. This document assesses the 2 scenarios where this problem is most evident: coronary revascularization and the treatment of aortic stenosis. The document analyzes the situation of coronary revascularization in Spain, and the causes that may explain the differences between the number of patients who currently undergo percutaneous revascularization and those who undergo coronary surgery. In contrast, treatment of aortic stenosis through transcatheter aortic valve implantation will lead to a foreseeable reduction in the number of candidates for surgical replacement. Several international scientific societies have published the requirements on training and experience and the necessary operator and center volumes to implement a transcatheter aortic valve implantation program, conditions that the Spanish Society of Cardiology, adopting a patient-centered approach, considers absolutely essential. Given that the 2 forms of intervention (percutaneous and surgical) are complementary, multidisciplinary patient assessment (Heart Team) remains crucial to offer the best treatment option. In this scenario of diverse approaches, a key figure is the clinical cardiologist. Finally, the changes currently occurring in the treatment of structural heart disease will, in future, lead to the performance of procedures requiring the participation of professionals from both specialties. This approach will require a redesign of current training programs.

Predicting operative mortality in octogenarians for isolated coronary artery bypass grafting surgery: a retrospective study

Background

Available cardiac surgery risk scores have not been validated in octogenarians. Our objective was to compare the predictive ability of the Society of Thoracic Surgeons (STS) score, EuroSCORE I, and EuroSCORE II in elderly patients undergoing isolated coronary artery bypass grafting surgery (CABG).

Methods

All patients who underwent isolated CABG (2002 – 2008) were identified from the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease (APPROACH) registry. All patients aged 80 and older (n = 304) were then matched 1:2 with a randomly selected control group of patients under age 80 (n = 608 of 4732). Risk scores were calculated. Discriminatory accuracy of the risk models was assessed by plotting the areas under the receiver operator characteristic (AUC) and comparing the observed to predicted operative mortality.

Results

Octogenarians had a significantly higher predicted mortality by STS Score (3 ± 2% vs. 1 ± 1%; p < 0.001), additive EuroSCORE (8 ± 3% vs. 4 ± 3%; p < 0.001), logistic EuroSCORE (15 ± 14% vs. 5 ± 6%; p < 0.001), and EuroSCORE II (4 ± 3% vs. 2 ± 2%; p < 0.001) compared to patients under age 80 years. Observed mortality was 2% and 1% for patients age 80 and older and under age 80, respectively (p = 0.323). AUC revealed areas for STS, additive and logistic EuroSCORE I and EuroSCORE II, respectively, for patients age 80 and older (0.671, 0.709, 0.694, 0.794) and under age 80 (0.829, 0.750, 0.785, 0.845).

Conclusion

All risk prediction models assessed overestimated surgical risk, particularly in octogenarians. EuroSCORE II demonstrated better discriminatory accuracy in this population. Inclusion of new variables into these risk models, such as frailty, may allow for more accurate prediction of true operative risk.

Hospital Surgical Volumes and Mortality after Coronary Artery Bypass Grafting: Using International Comparisons to Determine a Safe Threshold

OBJECTIVE

To estimate a safe minimum hospital volume for hospitals performing coronary artery bypass graft (CABG) surgery.

DATA SOURCE

Hospital data on all publicly funded CABG in five European countries, 2007-2009 (106,149 patients).

DESIGN

Hierarchical logistic regression models to estimate the relationship between hospital volume and mortality, allowing for case mix. Segmented regression analysis to estimate a threshold.

FINDINGS

The 30-day in-hospital mortality rate was 3.0 percent overall, 5.2 percent (95 percent CI: 4.0-6.4) in low-volume hospitals, and 2.1 percent (95 percent CI: 1.8-2.3) in high-volume hospitals. There is a significant curvilinear relationship between volume and mortality, flatter above 415 cases per hospital per year.

CONCLUSIONS

There is a clear relationship between hospital CABG volume and mortality in Europe, implying a "safe" threshold volume of 415 cases per year.

Variation between Hospitals with Regard to Diagnostic Practice, Coding Accuracy, and Case-Mix. A Retrospective Validation Study of Administrative Data versus Medical Records for Estimating 30-Day Mortality after Hip Fracture

BACKGROUND

The purpose of this study was to assess the validity of patient administrative data (PAS) for calculating 30-day mortality after hip fracture as a quality indicator, by a retrospective study of medical records.

METHODS

We used PAS data from all Norwegian hospitals (2005-2009), merged with vital status from the National Registry, to calculate 30-day case-mix adjusted mortality for each hospital (n = 51). We used stratified sampling to establish a representative sample of both hospitals and cases. The hospitals were stratified according to high, low and medium mortality of which 4, 3, and 5 hospitals were sampled, respectively. Within hospitals, cases were sampled stratified according to year of admission, age, length of stay, and vital 30-day status (alive/dead). The final study sample included 1043 cases from 11 hospitals. Clinical information was abstracted from the medical records. Diagnostic and clinical information from the medical records and PAS were used to define definite and probable hip fracture. We used logistic regression analysis in order to estimate systematic between-hospital variation in unmeasured confounding. Finally, to study the consequences of unmeasured confounding for identifying mortality outlier hospitals, a sensitivity analysis was performed.

RESULTS

The estimated overall positive predictive value was 95.9% for definite and 99.7% for definite or probable hip fracture, with no statistically significant differences between hospitals. The standard deviation of the additional, systematic hospital bias in mortality estimates was 0.044 on the logistic scale. The effect of unmeasured confounding on outlier detection was small to moderate, noticeable only for large hospital volumes.

CONCLUSIONS

This study showed that PAS data are adequate for identifying cases of hip fracture, and the effect of unmeasured case mix variation was small. In conclusion, PAS data are adequate for calculating 30-day mortality after hip-fracture as a quality indicator in Norway.