Comparing AMI mortality among hospitals in patients 65 years of age and older: evaluating methods of risk adjustment

Sex Differences and Temporal Trends in Revascularization and Outcomes of ST-Elevation Myocardial Infarction in Older Adults in the United States

BACKGROUND

Previous studies have suggested that in-hospital mortality is higher in younger women with ST-segment elevation myocardial infarction (STEMI) than in men. However, more coronary artery disease diagnoses occurred in patients older than 60 years.

AIM OF THE STUDY

This study sought to investigate the temporal trends and sex differences in revascularization and in-hospital outcomes in older STEMI patients.

METHODS

National Inpatient Sample databases from 2005-2014 were utilized to identify all STEMI patients with age greater than 60 years old. We studied the temporal trends and sex differences in revascularization therapies and in-hospital mortality.

RESULTS

From 2005-2014, there were 192,204 older adults diagnosed with STEMI. Older women with STEMI were less likely to receive reperfusion (percutaneous coronary intervention (PCI) adjusted OR: 0.90; 95% CI: 0.87-0.92) compared to older men. Also, the adjusted odds ratio comparing the likelihood of receiving PCI between women and men decreased by an annual average of 0.9% (p = 0.028). Older women had higher in-hospital mortality than men (adjusted OR: 1.12; 95% CI: 1.08 to 1.17). There was no significant change of adjusted in-hospital mortality in both genders (all p >0.05).

CONCLUSIONS

Older women were less likely to receive revascularization for STEMI, and this gap was increasing during the study period. Older women had higher in-hospital mortality as compared with older men, but there was no significant temporal change for both genders. These findings present an opportunity to bridge the gender-gap in providing care to older patients with STEMI.

Associations between initial American Board of Internal Medicine certification and maintenance of certification status of attending physicians and in-hospital mortality of patients with acute myocardial infarction or congestive heart failure: a retrospective cohort study of hospitalisations in Pennsylvania, USA

OBJECTIVE

To determine whether internists' initial specialty certification and the maintenance of that certification (MOC) is associated with lower in-hospital mortality for their patients with acute myocardial infarction (AMI) or congestive heart failure (CHF).

DESIGN

Retrospective cohort study of hospitalisations in Pennsylvania, USA, from 2012 to 2017.

SETTING

All hospitals in Pennsylvania.

PARTICIPANTS

All 184 115 hospitalisations for primary diagnoses of AMI or CHF where the attending physician was a self-designated internist.

PRIMARY OUTCOME MEASURE

In-hospital mortality.

RESULTS

Of the 2575 physicians, 2238 had initial certification and 820 were eligible for MOC. After controlling for patient demographics and clinical characteristics, hospital-level factors and physicians' demographic and medical school characteristics, both initial certification and MOC were associated with lower mortality. The adjusted OR for initial certification was 0.835 (95% CI 0.756 to 0.922; p<0.001). Patients cared for by physicians with initial certification had a 15.87% decrease in mortality compared with those cared for by non-certified physicians (mortality rate difference of 5.09 per 1000 patients; 95% CI 2.12 to 8.05; p<0.001). The adjusted OR for MOC was 0.804 (95% CI 0.697 to 0.926; p=0.003). Patients cared for by physicians who completed MOC had an 18.91% decrease in mortality compared with those cared for by MOC lapsed physicians (mortality rate difference of 6.22 per 1000 patients; 95% CI 2.0 to 10.4; p=0.004).

CONCLUSIONS

Initial certification was associated with lower mortality for AMI or CHF. Moreover, for patients whose physicians had initial certification, an additional advantage was associated with its maintenance.

Generalizability of Cardiovascular Disease Clinical Prediction Models: 158 Independent External Validations of 104 Unique Models

Background:

While clinical prediction models (CPMs) are used increasingly commonly to guide patient care, the performance and clinical utility of these CPMs in new patient cohorts is poorly understood.

Methods:

We performed 158 external validations of 104 unique CPMs across 3 domains of cardiovascular disease (primary prevention, acute coronary syndrome, and heart failure). Validations were performed in publicly available clinical trial cohorts and model performance was assessed using measures of discrimination, calibration, and net benefit. To explore potential reasons for poor model performance, CPM-clinical trial cohort pairs were stratified based on relatedness, a domain-specific set of characteristics to qualitatively grade the similarity of derivation and validation patient populations. We also examined the model-based C-statistic to assess whether changes in discrimination were because of differences in case-mix between the derivation and validation samples. The impact of model updating on model performance was also assessed.

Results:

Discrimination decreased significantly between model derivation (0.76 [interquartile range 0.73–0.78]) and validation (0.64 [interquartile range 0.60–0.67], P<0.001), but approximately half of this decrease was because of narrower case-mix in the validation samples. CPMs had better discrimination when tested in related compared with distantly related trial cohorts. Calibration slope was also significantly higher in related trial cohorts (0.77 [interquartile range, 0.59–0.90]) than distantly related cohorts (0.59 [interquartile range 0.43–0.73], P=0.001). When considering the full range of possible decision thresholds between half and twice the outcome incidence, 91% of models had a risk of harm (net benefit below default strategy) at some threshold; this risk could be reduced substantially via updating model intercept, calibration slope, or complete re-estimation.

Conclusions:

There are significant decreases in model performance when applying cardiovascular disease CPMs to new patient populations, resulting in substantial risk of harm. Model updating can mitigate these risks. Care should be taken when using CPMs to guide clinical decision-making.

Are medical record front page data suitable for risk adjustment in hospital performance measurement? Development and validation of a risk model of in-hospital mortality after acute myocardial infarction

OBJECTIVES

To develop a model of in-hospital mortality using medical record front page (MRFP) data and assess its validity in case-mix standardisation by comparison with a model developed using the complete medical record data.

DESIGN

A nationally representative retrospective study.

SETTING

Representative hospitals in China, covering 161 hospitals in modelling cohort and 156 hospitals in validation cohort.

PARTICIPANTS

Representative patients admitted for acute myocardial infarction. 8370 patients in modelling cohort and 9704 patients in validation cohort.

PRIMARY OUTCOME MEASURES

In-hospital mortality, which was defined explicitly as death that occurred during hospitalisation, and the hospital-level risk standardised mortality rate (RSMR).

RESULTS

A total of 14 variables were included in the model predicting in-hospital mortality based on MRFP data, with the area under receiver operating characteristic curve of 0.78 among modelling cohort and 0.79 among validation cohort. The median of absolute difference between the hospital RSMR predicted by hierarchical generalised linear models established based on MRFP data and complete medical record data, which was built as 'reference model', was 0.08% (10th and 90th percentiles: -1.8% and 1.6%). In the regression model comparing the RSMR between two models, the slope and intercept of the regression equation is 0.90 and 0.007 in modelling cohort, while 0.85 and 0.010 in validation cohort, which indicated that the evaluation capability from two models were very similar.

CONCLUSIONS

The models based on MRFP data showed good discrimination and calibration capability, as well as similar risk prediction effect in comparison with the model based on complete medical record data, which proved that MRFP data could be suitable for risk adjustment in hospital performance measurement.

Peri-Procedural Blood Pressure Changes and Their Relationship with MACE in Patients Undergoing Percutaneous Coronary Intervention: A Cross-Sectional Study

Background

Peri-procedural blood-pressure (BP) changes were investigated and correlated to Major adverse cardiovascular events (MACE) as predictor of outcome for patients undergoing percutaneous coronary intervention (PCI); whether acute coronary syndrome (Unstable angina, or MI; STEMI or NSTEMI) or scheduled for elective PCI.

Methods

Resting BP in the 204 recruited patients undergoing PCI throughout 2018 was measured thrice – in the ward before transferring to the cardiac catheterization lab (cath lab), in the cath lab, and after transfer to the recovery room. Patients were categorized based on their systolic and diastolic BP peri-procedural difference as systolic (SBP): with a large difference (>20 mmHg, n=47), with a small difference (≤20 mmHg, n=157) (shock patients excluded); diastolic (DBP): with a large difference (>10 mmHg, n=65), and with a small difference (≤10 mmHg, n=139). The primary end-points were MACE including all-cause mortality, non-fatal myocardial infarction, and stroke during the hospital stay. The Mann–Whitney U and Chi-square tests were used to analyze the data accordingly (p<0.005).

Results

Within the category of MACE, cardiac mortality was the only adverse cardiac event encountered in the study sample. Cardiac mortality was significantly higher in both the large SBP-difference group versus the other group (10.6% vs 0.6%, p=0.003) and the large DBP-difference group versus the small-difference group (7.7% vs 0.7%, p=0.013).

Conclusion

Peri-procedural systolic and diastolic BP differences, greater than 20 mmHg and 10 mmHg, respectively, correlated with MACE in all patients undergoing PCI.

Differential Outcomes With Edetate Disodium-Based Treatment Among Stable Post Anterior vs. Non-Anterior Myocardial Infarction Patients

BACKGROUND

The Trial to Assess Chelation Therapy (TACT) found that chelation therapy significantly reduced clinical events in patients with a history of myocardial infarction (MI). The initial report of TACT included the observation of an interaction between edetate disodium infusions and MI location, as well as diabetes. Thus, we examined in greater detail the effect of edetate disodium chelation therapy as a function of MI location and diabetes.

METHODS

Patients (n = 1708) at least 6 weeks post-MI and age ≥ 50 were randomized to receive 40 infusions of a 500 mL chelation solution or placebo (median follow-up 55 months). The effect of edetate disodium on the primary outcome (all-cause mortality, MI, stroke, hospitalization for angina, or coronary revascularization) was assessed as a function of MI location using log-rank test and Cox regression model, adjusting for other prognostic variables.

RESULTS

Among patients with post anterior MI (n = 674), chelation was associated with a lower risk of the primary endpoint (HR 0.63, 95% CI 0.47-0.86, p = 0.003) among anterior MI patients, but not in post non-anterior MI (n = 1034) patients (HR 0.96, 95% CI 0.77-1.20, p = 0.702) (p-for-interaction = 0.032). The point estimates for each component of the primary endpoint favored chelation therapy. The differing treatment effect in patients with post anterior vs. non-anterior MI was consistent among patients with or without diabetes and remained significant after adjusting for other prognostic variables (p < 0.01).

CONCLUSIONS

Edetate disodium infusions reduced the risk of cardiovascular events among patients with a prior anterior MI. Future studies should focus on replicating these results and understanding the mechanisms of benefit.

The Value of Claims-Based Nontraditional Risk Factors in Predicting Long-term Mortality After MitraClip Procedure

BACKGROUND

We sought to identify nontraditional risk factors coded in administrative claims data and evaluate their ability to improve prediction of long-term mortality in patients undergoing percutaneous mitral valve repair.

METHODS

Patients undergoing transcatheter mitral valve repair using MitraClip implantation between September 28, 2010, and September 30, 2015 were identified among Medicare fee-for-service beneficiaries. We used nested Cox regression models to identify claims codes predictive of long-term mortality. Four groups of variables were introduced sequentially: cardiac and noncardiac risk factors, presentation characteristics, and nontraditional risk factors.

RESULTS

A total of 3782 patients from 280 clinical sites received treatment with MitraClip over the study period. During the follow-up period, 1114 (29.5%) patients died with a median follow-up time period of 13.6 (9.6 to 17.3) months. The discrimination of a model to predict long-term mortality including only cardiac risk factors was 0.58 (0.55 to 0.60). Model discrimination improved with the addition of noncardiac risk factors (c = 0.63, 0.61 to 0.65; integrated discrimination improvement [IDI] = 0.038, P < 0.001), and with the subsequent addition of presentation characteristics (c = 0.67, 0.65 to 0.69; IDI = 0.033, P < 0.001 compared with the second model). Finally, the addition of nontraditional risk factors significantly improved model discrimination (c = 0.70, 0.68 to 0.72; IDI = 0.019, P < 0.001, compared with the third model).

CONCLUSIONS

Risk-prediction models, which include nontraditional risk factors as identified in claims data, can be used to predict long-term mortality risk more accurately in patients who have undergone MitraClip procedures.

Temporal Trends in the Clinical Acuity of Patients with ST-Segment Elevation Myocardial Infarction

BACKGROUND

Despite advances in ST-segment elevation myocardial infarction (STEMI) systems of care over the last decade, studies have shown no improvement in risk-adjusted mortality. It has been hypothesized that the population presenting to the catheterization laboratory has become sicker over time, in ways not accurately captured by current mortality models. The objective of this study was to examine changes in the clinical characteristics and in-hospital case fatality rate of the STEMI population treated with early percutaneous coronary intervention (PCI).

METHODS

We conducted a retrospective analysis of a nationwide inpatient database for the period 2004-2012. All patients with a diagnosis of STEMI who underwent PCI within 24 hours of admission were identified. The primary outcome was in-hospital mortality.

RESULTS

From 2004 to 2012 there was a consistent increase in unadjusted in-hospital mortality (3.9% in 2004 and 4.7% in 2012, odds ratio_year 1.03; 95% confidence interval 1.01-1.04). During this time there was an increase in the proportion of patients with ≥3 Elixhauser comorbidities (14.8% vs 29.0%, P_trend < .001). Intubation or cardiac arrest on presentation increased from 3.2% to 7.8% (P_trend < .001) and had a strong, independent association with mortality. After multivariable adjustment using a model that incorporated the increasing trend in intubation/cardiac arrest, mortality decreased over time (odds ratio_year 0.95; 95% confidence interval 0.94-0.97).

CONCLUSIONS

During a period that corresponds to improvement in STEMI quality of care, risk-adjusted in-hospital mortality declined. An increase in comorbidities, and more importantly in the proportion of patients presenting with extreme-risk features, may explain the overall "null" effect regarding in-hospital mortality despite improvements in timely reperfusion.

Prognostic impact of blood pressure and heart rate at admission on in-hospital mortality after primary percutaneous intervention for acute myocardial infarction with ST-segment elevation in western Romania

Background

The purpose of this retrospective study was to evaluate the prognostic impact of systolic blood pressure (SBP) and heart rate (HR) on in-hospital mortality in ST-segment elevation acute myocardial infarction (STEMI) patients, after primary percutaneous intervention (PCI).

Patients and methods

The study included 294 patients admitted for STEMI. They were divided into five groups according to the SBP at admission: group I, <105 mmHg; group II, 105–125 mmHg; group III, 126–140 mmHg; group IV, 141–158 mmHg; and group V, ≥159 mmHg. Increased HR was defined as ≥80 beats per minute (bpm). In-hospital death was defined as all-cause death during admission and classified into cardiac and noncardiac death.

Results

Among the 294 patients admitted for STEMI, 218 (74%) were men. The mean age was 62±17 years. In-hospital mortality rate was 6% (n=18), with 11 (3.7%) deaths having cardiac causes. The highest mortality was registered in group I (n=9, 16%, P=0.018). Compared to the other groups, group I patients were older (P=0.033), more often smokers (P=0.026), and had a history of myocardial infarction (P=0.003), systemic hypertension (P=0.023), diabetes (P=0.041), or chronic kidney disease (P=0.0200). They more often had a HR ≥80 bpm (P=0.028) and a Killip class 3 or 4 at admission (P=0.020). The peak creatine phosphokinase-MB level was significantly higher in this group (P=0.005), while the angiographic findings more often identified as culprit lesions were the right coronary artery (P=0.005), the left main trunk (P=0.040), or a multivessel coronary artery disease (P=0.044). Multivariate analysis showed that group I patients had a significantly higher risk for both all-cause death (P=0.006) and cardiac death (P=0.003). Patients with HR ≥80 bpm also had higher mortality rates (P=0.0272 for general mortality and P=0.0280 for cardiac mortality).

Conclusion

The present study suggests that SBP <105 mmHg and HR ≥80 bpm at admission of STEMI patients are associated with a higher risk of in-hospital death, even after primary PCI.

Predicting In-Hospital Mortality in Patients With Acute Myocardial Infarction

BACKGROUND

As a foundation for quality improvement, assessing clinical outcomes across hospitals requires appropriate risk adjustment to account for differences in patient case mix, including presentation after cardiac arrest.

OBJECTIVES

The aim of this study was to develop and validate a parsimonious patient-level clinical risk model of in-hospital mortality for contemporary patients with acute myocardial infarction.

METHODS

Patient characteristics at the time of presentation in the ACTION (Acute Coronary Treatment and Intervention Outcomes Network) Registry-GWTG (Get With the Guidelines) database from January 2012 through December 2013 were used to develop a multivariate hierarchical logistic regression model predicting in-hospital mortality. The population (243,440 patients from 655 hospitals) was divided into a 60% sample for model derivation, with the remaining 40% used for model validation. A simplified risk score was created to enable prospective risk stratification in clinical care.

RESULTS

The in-hospital mortality rate was 4.6%. Age, heart rate, systolic blood pressure, presentation after cardiac arrest, presentation in cardiogenic shock, presentation in heart failure, presentation with ST-segment elevation myocardial infarction, creatinine clearance, and troponin ratio were all independently associated with in-hospital mortality. The C statistic was 0.88, with good calibration. The model performed well in subgroups based on age; sex; race; transfer status; and the presence of diabetes mellitus, renal dysfunction, cardiac arrest, cardiogenic shock, and ST-segment elevation myocardial infarction. Observed mortality rates varied substantially across risk groups, ranging from 0.4% in the lowest risk group (score <30) to 49.5% in the highest risk group (score >59).

CONCLUSIONS

This parsimonious risk model for in-hospital mortality is a valid instrument for risk adjustment and risk stratification in contemporary patients with acute myocardial infarction.

Using nationwide ‘big data’ from linked electronic health records to help improve outcomes in cardiovascular diseases: 33 studies using methods from epidemiology, informatics, economics and social science in the ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER) programme

Background

Electronic health records (EHRs), when linked across primary and secondary care and curated for research use, have the potential to improve our understanding of care quality and outcomes.

Objective

To evaluate new opportunities arising from linked EHRs for improving quality of care and outcomes for patients at risk of or with coronary disease across the patient journey.

Design

Epidemiological cohort, health informatics, health economics and ethnographic approaches were used.

Setting

230 NHS hospitals and 226 general practices in England and Wales.

Participants

Up to 2 million initially healthy adults, 100,000 people with stable coronary artery disease (SCAD) and up to 300,000 patients with acute coronary syndrome.

Main outcome measures

Quality of care, fatal and non-fatal cardiovascular disease (CVD) events.

Data platform and methods

We created a novel research platform [ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER)] based on linkage of four major sources of EHR data in primary care and national registries. We carried out 33 complementary studies within the CALIBER framework. We developed a web-based clinical decision support system (CDSS) in hospital chest pain clinics. We established a novel consented prognostic clinical cohort of SCAD patients.

Results

CALIBER was successfully established as a valid research platform based on linked EHR data in nearly 2 million adults with > 600 EHR phenotypes implemented on the web portal (seehttps://caliberresearch.org/portal). Despite national guidance, key opportunities for investigation and treatment were missed across the patient journey, resulting in a worse prognosis for patients in the UK compared with patients in health systems in other countries. Our novel, contemporary, high-resolution studies showed heterogeneous associations for CVD risk factors across CVDs. The CDSS did not alter the decision-making behaviour of clinicians in chest pain clinics. Prognostic models using real-world data validly discriminated risk of death and events, and were used in cost-effectiveness decision models.

Conclusions

Emerging ‘big data’ opportunities arising from the linkage of records at different stages of a patient’s journey are vital to the generation of actionable insights into the diagnosis, risk stratification and cost-effective treatment of people at risk of, or with, CVD.

Future work

The vast majority of NHS data remain inaccessible to research and this hampers efforts to improve efficiency and quality of care and to drive innovation. We propose three priority directions for further research. First, there is an urgent need to ‘unlock’ more detailed data within hospitals for the scale of the UK’s 65 million population. Second, there is a need for scaled approaches to using EHRs to design and carry out trials, and interpret the implementation of trial results. Third, large-scale, disease agnostic genetic and biological collections linked to such EHRs are required in order to deliver precision medicine and to innovate discovery.

Study registration

CALIBER studies are registered as follows: study 2 – NCT01569139, study 4 – NCT02176174 and NCT01164371, study 5 – NCT01163513, studies 6 and 7 – NCT01804439, study 8 – NCT02285322, and studies 26–29 – NCT01162187. Optimising the Management of Angina is registered as Current Controlled Trials ISRCTN54381840.

Funding

The National Institute for Health Research (NIHR) Programme Grants for Applied Research programme (RP-PG-0407-10314) (all 33 studies) and additional funding from the Wellcome Trust (study 1), Medical Research Council Partnership grant (study 3), Servier (study 16), NIHR Research Methods Fellowship funding (study 19) and NIHR Research for Patient Benefit (study 33).

China PEACE risk estimation tool for in-hospital death from acute myocardial infarction: an early risk classification tree for decisions about fibrinolytic therapy

OBJECTIVES

As the predominant approach to acute reperfusion for ST segment elevation myocardial infarction (STEMI) in many countries, fibrinolytic therapy provides a relative risk reduction for death of ∼16% across the range of baseline risk. For patients with low baseline mortality risk, fibrinolytic therapy may therefore provide little benefit, which may be offset by the risk of major bleeding. We aimed to construct a tool to determine if it is possible to identify a low-risk group among fibrinolytic therapy-eligible patients.

DESIGN

Cross-sectional study.

SETTING

The China Patient-centered Evaluative Assessment of Cardiac Events (PEACE) study includes a nationally representative retrospective sample of patients admitted with acute myocardial infarction (AMI) in 162 hospitals.

PARTICIPANTS

3741 patients with STEMI who were fibrinolytic-eligible but did not receive reperfusion therapy.

MAIN OUTCOME MEASURES

In-hospital mortality, which was defined as a composite of death occurring within hospitalisation or withdrawal from treatment due to a terminal status at discharge.

RESULTS

In the study cohort, the in-hospital mortality was 14.7%. In the derivation cohort and the validation cohort, the combination of systolic blood pressure (≥100 mm Hg), age (<60 years old) and gender (male) identified one-fifth of the cohort with an average mortality rate of <3.0%. Half of this low risk group-those with non-anterior AMI-had an average in-hospital death risk of 1.5%.

CONCLUSIONS

Nearly, one in five patients with STEMI who are eligible for fibrinolytic therapy are at a low risk for in-hospital death. Three simple factors available at the time of presentation can identify these individuals and support decision-making about the use of fibrinolytic therapy.

TRIAL REGISTRATION NUMBER

NCT01624883.

Comparing Risk-adjusted Hospital Mortality for CABG and AMI Patients

The objectives of this study were to compare the risk-adjusted mortality of coronary artery bypass graft (CABG) and acute myocardial infarction (AMI) patients simultaneously in six hospitals in Seoul, Korea, and to investigate the relationship between these performance measures by developing a predictive model of mortality. The medical records of 749 AMI and 564 CABG patients were reviewed. A predictive model was developed using logistic regression, including 170 variables selected as risk factors for risk adjustment. The validity of our predictive model was demonstrated to be within an acceptable range. The results showed that one hospital with a significantly low AMI mortality rate also had a low CABG mortality rate, while another hospital with a significantly high AMI mortality rate also had a high CABG mortality rate. Our results implied that hospitals providing good-quality medical management of coronary artery disease also provided a good-quality surgical service.

Evaluation of Acute Myocardial Infarction In-hospital Mortality Using a Risk-adjustment Model Based on Japanese Administrative Data

This study aimed to develop a new risk-adjustment method to assess acute myocardial infarction (AMI) in-hospital mortality. Risk-adjustment was based on variables obtained from administrative data from Japanese hospitals, and included factors such as age, gender, primary diagnosis and co-morbidity. The infarct location was determined using the criteria of the International Classification of Diseases (10th version). Potential co-morbidity risk factors for mortality were selected based on previous studies and their critical influence analysed to identify major co-morbidities. The remaining minor co-morbidities were then divided into two groups based on their medical implications. The major co-morbidities included shock, pneumonia, cancer and chronic renal failure. The two minor co-morbidity groups also demonstrated a substantial impact on mortality. The model was then used to assess clinical performance in the participating hospitals. Our model reliably employed the available data for the risk-adjustment of AMI mortality and provides a new approach to evaluating clinical performance.

Trends in Coronary Angiography, Revascularization, and Outcomes of Cardiogenic Shock Complicating Non-ST-Elevation Myocardial Infarction

Early revascularization is the mainstay of treatment for cardiogenic shock (CS) complicating acute myocardial infarction. However, data on the contemporary trends in management and outcomes of CS complicating non-ST-elevation myocardial infarction (NSTEMI) are limited. We used the 2006 to 2012 Nationwide Inpatient Sample databases to identify patients aged ≥ 18 years with NSTEMI with or without CS. Temporal trends and differences in coronary angiography, revascularization, and outcomes were analyzed. Of 2,191,772 patients with NSTEMI, 53,800 (2.5%) had a diagnosis of CS. From 2006 to 2012, coronary angiography rates increased from 53.6% to 60.4% in patients with NSTEMI with CS (ptrend <0.001). Among patients who underwent coronary angiography, revascularization rates were significantly higher in patients with CS versus without CS (72.5% vs 62.6%, p <0.001). Patients with NSTEMI with CS had significantly higher risk-adjusted in-hospital mortality (odds ratio 10.09, 95% confidence interval 9.88 to 10.32) as compared to those without CS. In patients with CS, an invasive strategy was associated with lower risk-adjusted in-hospital mortality (odds ratio 0.43, 95% confidence interval 0.42 to 0.45). Risk-adjusted in-hospital mortality, length of stay, and total hospital costs decreased over the study period in patients with and without CS (ptrend <0.001). In conclusion, we observed an increasing trend in coronary angiography and decreasing trend in in-hospital mortality, length of stay, and total hospital costs in patients with NSTEMI with and without CS. Despite these positive trends, overall coronary angiography and revascularization rates remain less than optimal and in-hospital mortality unacceptably high in patients with NSTEMI and CS.

Development of a Hospital Outcome Measure Intended for Use With Electronic Health Records: 30-Day Risk-standardized Mortality After Acute Myocardial Infarction

BACKGROUND

Electronic health records (EHRs) offer the opportunity to transform quality improvement by using clinical data for comparing hospital performance without the burden of chart abstraction. However, current performance measures using EHRs are lacking.

METHODS

With support from the Centers for Medicare & Medicaid Services (CMS), we developed an outcome measure of hospital risk-standardized 30-day mortality rates for patients with acute myocardial infarction for use with EHR data. As no appropriate source of EHR data are currently available, we merged clinical registry data from the Action Registry-Get With The Guidelines with claims data from CMS to develop the risk model (2009 data for development, 2010 data for validation). We selected candidate variables that could be feasibly extracted from current EHRs and do not require changes to standard clinical practice or data collection. We used logistic regression with stepwise selection and bootstrapping simulation for model development.

RESULTS

The final risk model included 5 variables available on presentation: age, heart rate, systolic blood pressure, troponin ratio, and creatinine level. The area under the receiver operating characteristic curve was 0.78. Hospital risk-standardized mortality rates ranged from 9.6% to 13.1%, with a median of 10.7%. The odds of mortality for a high-mortality hospital (+1 SD) were 1.37 times those for a low-mortality hospital (-1 SD).

CONCLUSIONS

This measure represents the first outcome measure endorsed by the National Quality Forum for public reporting of hospital quality based on clinical data in the EHR. By being compatible with current clinical practice and existing EHR systems, this measure is a model for future quality improvement measures.

Optimal use of available claims to identify a Medicare population free of coronary heart disease

We examined claims-based approaches for identifying a study population free of coronary heart disease (CHD) using data from 8,937 US blacks and whites enrolled during 2003-2007 in a prospective cohort study linked to Medicare claims. Our goal was to minimize the percentage of persons at study entry with self-reported CHD (previous myocardial infarction or coronary revascularization). We assembled 6 cohorts without CHD claims by requiring 6 months, 1 year, or 2 years of continuous Medicare fee-for-service insurance coverage prior to study entry and using either a fixed-window or all-available look-back period. We examined adding CHD-related claims to our "base algorithm," which included claims for myocardial infarction and coronary revascularization. Using a 6-month fixed-window look-back period, 17.8% of participants without claims in the base algorithm reported having CHD. This was reduced to 3.6% using an all-available look-back period and adding other CHD claims to the base algorithm. Among cohorts using all-available look-back periods, increasing the length of continuous coverage from 6 months to 1 or 2 years reduced the sample size available without lowering the percentage of persons with self-reported CHD. This analysis demonstrates approaches for developing a CHD-free cohort using Medicare claims.

Characteristics and Outcomes of Patients with Acute Myocardial Infarction at Non-PCI Capable Hospitals in 2007 and in 2014

Background. There is little known about whether characteristics and outcomes of patients with acute myocardial infarction (AMI) have changed over the years in non-PCI capable hospitals in real-life. Our aim was to assess them between 2007 and 2014. Methods. It was a retrospective cohort study. Characteristics and in-hospital mortality (standardized in cases of different characteristics between the groups by original simple method) were assessed for all patients with non-ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction (STEMI) at two non-PCI capable hospitals: one in 2007 (n = 104) and another in 2014 (n = 58). Results. In 2014, females were older than in 2007 (80.18 ± 7.54 versus 76.15 ± 8.77, p = 0.011), males were younger (71.61 ± 11.22 versus 79.20 ± 7.63, p = 0.019), less had renal failure (RF) (19% versus 34.6%, p < 0.0001) and reinfarction (13.8% versus 35.6%, p < 0.0001), and the proportion of males (31% versus 43.3%, p = 0.001) and the proportion of NSTEMI (60.3 versus 69.2, p < 0.0001) decreased. In cases of STEMI there were no differences in patient characteristics. STEMI (18.8% versus 21.7%) and standardized mortalities by gender, RF, and reinfarction NSTEMI (19.47%, 15.34%, and 17.5%, resp., versus 17.1%) showed no differences between 2007 and 2014. Conclusions. There were some differences in patient characteristics but not in mortality for AMI at non-PCI capable hospitals between 2007 and 2014.

Patterns of use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers among patients with acute myocardial infarction in China from 2001 to 2011: China PEACE-Retrospective AMI Study

Background

Chinese and U.S. guidelines recommend angiotensin‐converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) for all patients with acute myocardial infarction (AMI) in the absence of contraindications as either a Class I or Class IIa recommendation. Little is known about the use and trends of ACEI/ARB therapy in China over the past decade.

Methods and Results

Using nationally representative data from the China Patient‐centered Evaluative Assessment of Cardiac Events Retrospective Study of Acute Myocardial Infarction (China PEACE‐Retrospective AMI Study), we assessed use of ACEI/ARB therapy in 2001, 2006, and 2011, overall and across geographic regions and strata of estimated mortality risk, and predictors of ACEI/ARB therapy, among patients with Class I indication by Chinese guidelines. The weighted rate of ACEI/ARB therapy increased from 62.0% in 2001 to 71.4% in 2006, decreasing to 67.6% in 2011. Use was low across all 5 geographic regions. By strata of estimated mortality risk, in 2001, rates of therapy increased with increasing risk; however, by 2011, this reversed and those at higher risk were less likely to be treated (70.7% in lowest‐risk quintile vs. 63.5% in the highest‐risk quintile; P<0.001).

Conclusion

One third of Chinese AMI patients with Class I indications do not receive ACEI/ARB therapy during hospitalization, with little improvement in rates over time. Patients at higher mortality risk in 2011 were less likely to be treated, highlighting important opportunities to optimize the use of this cost‐effective therapy.

Clinical Trial Registration

URL: ClinicalTrials.gov. Unique identifier: NCT01624883.

GRACE score predicts heart failure admission following acute coronary syndrome

BACKGROUND

Congestive heart failure (CHF) is a common and preventable complication of acute coronary syndrome (ACS). Nevertheless, ACS risk scores have not been shown to predict CHF risk. We investigated whether the at-discharge Global Registry of Acute Coronary Events (GRACE) score predicts heart failure admission following ACS.

METHODS AND RESULTS

Five-year mortality and hospitalization data were obtained for patients admitted with ACS from June 1999 to September 2009 to a single centre of the GRACE registry. CHF was defined as any admission assigned WHO International Classification of Diseases 10 diagnostic code I50. The hazard ratio (HR) for CHF according to GRACE score was estimated in Cox models adjusting for age, gender and the presence of CHF on index admission. Among 1,956 patients, CHF was recorded on index admission in 141 patients (7%), and 243 (12%) were admitted with CHF over 3.8 median years of follow-up. Compared to the lowest quintile, patients in the highest GRACE score quintile had more CHF admissions (116 vs 17) and a shorter time to first admission (1.2 vs 2.0 years, HR 9.87, 95% CI 5.93-16.43). Per standard deviation increment in GRACE score, the instantaneous risk was more than two-fold higher (HR 2.28; 95% CI 2.02-2.57), including after adjustment for CHF on index admission, age and gender (HR 2.49; 95% CI 2.06-3.02). The C-statistic for CHF admission at 1-year was 0.74 (95% CI 0.70-0.79).

CONCLUSIONS

The GRACE score predicts CHF admission, and may therefore be used to target ACS patients at high risk of CHF with clinical monitoring and therapies.

Rankings versus reality in pancreatic cancer surgery: a real-world comparison

BACKGROUND

Patients are increasingly confronted with systems for rating hospitals. However, the correlations between publicized ratings and actual outcomes after pancreatectomy are unknown.

METHODS

The Massachusetts Division of Health Care Finance and Policy Hospital Inpatient Discharge Database was queried to identify pancreatic cancer resections carried out during 2005-2009. Hospitals performing fewer than 10 pancreatic resections in the 5-year period were excluded. Primary outcomes included mortality, complications, median length of stay (LoS) and a composite outcomes score (COS) combining primary outcomes. Ranks were determined and compared for: (i) volume, and (ii) ratings identified from consumer-directed hospital ratings including the US News & World Report (USN), Consumer Reports, Healthgrades and Hospital Compare. An inter-rater reliability analysis was performed and correlation coefficients (r) between outcomes and ratings, and between rating systems were calculated.

RESULTS

Eleven hospitals in which a total of 804 pancreatectomies were conducted were identified. Surgical volume correlated with overall outcome, but was not the strongest indicator. The highest correlation referred to that between USN rank and overall outcome. Mortality was most strongly correlated with Healthgrades ratings (r = 0.50); however, Healthgrades ratings demonstrated poorer correlations with all other outcomes. Consumer Reports ratings showed inverse correlations.

CONCLUSIONS

The plethora of publicly available hospital ratings systems demonstrates heterogeneity. Volume remains a good but imperfect indicator of surgical outcomes. Further systematic investigation into which measures predict quality outcomes in pancreatic cancer surgery will benefit both patients and providers.

Validity of the Global Registry of Acute Coronary Events risk score in prediction of acute myocardial infarction mortality in hospitalised Chinese patients aged 80 and over

AIM

To detect the validity of the Global Registry of Acute Coronary Events (GRACE) risk score in predicting acute myocardial infarction (AMI) mortality of Chinese inpatients aged 80 and over.

METHOD

Hospital mortality was defined as all-cause death rate of patients during hospitalisation. Using GRACE risk score to predict death risk, both discrimination (C statistic) and calibration (the predicted vs observed mortality based on the population with predicted risks) were evaluated.

RESULTS

Three hundred eighty-six patients presenting with ST segment elevation AMI (STEMI) and non-STEMI were enrolled. The GRACE risk score ranged between 151 and 297, and the mortality was 23.3%. The overall discriminatory capacity of the GRACE model was high (C statistic 0.767, CI: 0.712-0.822). There was a high correlation (R(2) = 0.833) between the predicted and observed hospitalised AMI mortality.

CONCLUSION

The GRACE score is a useful risk prediction model for hospital mortality of Chinese AMI patients aged 80 and over.

Does admission to a teaching hospital affect acute myocardial infarction survival?

PURPOSE

Previous studies have found that teaching hospitals produce better acute myocardial infarction (AMI) outcomes than nonteaching hospitals. However, these analyses generally excluded patients transferred out of nonteaching hospitals and did not study outcomes by patient risk level. The objective of this study was to determine whether admission to a teaching hospital was associated with greater survival after accounting for patient transfers and patient severity.

METHOD

This observational study used logistic models to examine the association between hospital teaching status and 30-day mortality of AMI patients, adjusting for patient comorbidities and common time trends. The sample included 1,309,554 Medicare patients admitted from 1996 to 2004 to 3,761 acute care hospitals for AMI. The primary outcome was 30-day all-cause, all-location mortality.

RESULTS

Mortality was slightly lower in minor teaching hospitals compared with nonteaching hospitals (odds ratio [OR] 0.97; 95% confidence interval [CI] 0.95-0.99) but not different between major teaching and nonteaching hospitals (OR 1.01; 95% CI 0.96-1.03). The odds of mortality in minor teaching hospitals decreased 4.2% relative to nonteaching hospitals during the seven-year period (OR from 0.98 to 0.94). There was no consistent pattern of association between teaching status and patient severity.

CONCLUSIONS

After correctly accounting for the ability of nonteaching hospitals to appropriately transfer patients in need of different care, there was no survival benefit on average for initial admission to a teaching hospital for AMI. Further more, higher-risk patients did not benefit from initial admission to teaching hospitals.

Relationship between hospital readmission and mortality rates for patients hospitalized with acute myocardial infarction, heart failure, or pneumonia

IMPORTANCE

The Centers for Medicare & Medicaid Services publicly reports hospital 30-day, all-cause, risk-standardized mortality rates (RSMRs) and 30-day, all-cause, risk-standardized readmission rates (RSRRs) for acute myocardial infarction, heart failure, and pneumonia. The evaluation of hospital performance as measured by RSMRs and RSRRs has not been well characterized.

OBJECTIVE

To determine the relationship between hospital RSMRs and RSRRs overall and within subgroups defined by hospital characteristics.

DESIGN, SETTING, AND PARTICIPANTS

We studied Medicare fee-for-service beneficiaries discharged with acute myocardial infarction, heart failure, or pneumonia between July 1, 2005, and June 30, 2008 (4506 hospitals for acute myocardial infarction, 4767 hospitals for heart failure, and 4811 hospitals for pneumonia). We quantified the correlation between hospital RSMRs and RSRRs using weighted linear correlation; evaluated correlations in groups defined by hospital characteristics; and determined the proportion of hospitals with better and worse performance on both measures.

MAIN OUTCOME MEASURES

Hospital 30-day RSMRs and RSRRs.

RESULTS

Mean RSMRs and RSRRs, respectively, were 16.60% and 19.94% for acute myocardial infarction, 11.17% and 24.56% for heart failure, and 11.64% and 18.22% for pneumonia. The correlations between RSMRs and RSRRs were 0.03 (95% CI, -0.002 to 0.06) for acute myocardial infarction, -0.17 (95% CI, -0.20 to -0.14) for heart failure, and 0.002 (95% CI, -0.03 to 0.03) for pneumonia. The results were similar for subgroups defined by hospital characteristics. Although there was a significant negative linear relationship between RSMRs and RSRRs for heart failure, the shared variance between them was only 2.9% (r2 = 0.029), with the correlation most prominent for hospitals with RSMR <11%.

CONCLUSION AND RELEVANCE

Risk-standardized mortality rates and readmission rates were not associated for patients admitted with an acute myocardial infarction or pneumonia and were only weakly associated, within a certain range, for patients admitted with heart failure.

Hospital strategies for reducing risk-standardized mortality rates in acute myocardial infarction

BACKGROUND

Despite recent improvements in survival after acute myocardial infarction (AMI), U.S. hospitals vary 2-fold in their 30-day risk-standardized mortality rates (RSMRs). Nevertheless, information is limited on hospital-level factors that may be associated with RSMRs.

OBJECTIVE

To identify hospital strategies that were associated with lower RSMRs.

DESIGN

Cross-sectional survey of 537 hospitals (91% response rate) and weighted multivariate regression by using data from the Centers for Medicare & Medicaid Services to determine the associations between hospital strategies and hospital RSMRs.

SETTING

Acute care hospitals with an annualized AMI volume of at least 25 patients.

PARTICIPANTS

Patients hospitalized with AMI between 1 January 2008 and 31 December 2009.

MEASUREMENTS

Hospital performance improvement strategies, characteristics, and 30-day RSMRs.

RESULTS

In multivariate analysis, several hospital strategies were significantly associated with lower RSMRs and in aggregate were associated with clinically important differences in RSMRs. These strategies included holding monthly meetings to review AMI cases between hospital clinicians and staff who transported patients to the hospital (RSMR lower by 0.70 percentage points), having cardiologists always on site (lower by 0.54 percentage points), fostering an organizational environment in which clinicians are encouraged to solve problems creatively (lower by 0.84 percentage points), not cross-training nurses from intensive care units for the cardiac catheterization laboratory (lower by 0.44 percentage points), and having physician and nurse champions rather than nurse champions alone (lower by 0.88 percentage points). Fewer than 10% of hospitals reported using at least 4 of these 5 strategies.

LIMITATION

The cross-sectional design demonstrates statistical associations but cannot establish causal relationships.

CONCLUSION

Several strategies, which are currently implemented by relatively few hospitals, are associated with significantly lower 30-day RSMRs for patients with AMI.

PRIMARY FUNDING SOURCE

The Agency for Healthcare Research and Quality, the United Health Foundation, and the Commonwealth Fund.

Validation of the GRACE score for prognosis in Indian patients with acute coronary syndromes

AIM

To validate the global registry of acute coronary events (GRACE) score in acute coronary syndromes (ACS) patients and study its angiographic correlation.

METHODS AND RESULTS

Two-hundred and thirty-five ACS patients were studied for the combined endpoint of all-cause in-hospital mortality and non-fatal infarction/reinfarction. We tested the predictive accuracy of the composite GRACE score using the receiver operating characteristics (ROC) curve. Lower systolic blood pressure (SBP) (odds ratio [OR] 7.93, P=0.005), ST-segment deviation (OR 7.79, P=0.02) and cardiac biomarker positivity (OR > 6.52, P=0.01) were significantly associated with events. Serum creatinine > 1.4 mg/dL showed a trend towards statistical significance (OR 4.14, P=0.05), whereas age > 50 years (OR 3.62, P=not significant [NS]) and Killips class 4 (OR 2.71, P=NS) showed good association. The best value for predicting events was a GRACE score of > 217 and these patients were more likely to have double/triple vessel disease (P = 0.0009). The C statistic for the GRACE score was 0.75.

CONCLUSION

Higher GRACE score predicts in-hospital events and more severe angiographic coronary artery disease (CAD).

Large between-center differences in outcome after moderate and severe traumatic brain injury in the international mission on prognosis and clinical trial design in traumatic brain injury (IMPACT) study

BACKGROUND

Differences between centers in patient outcome after traumatic brain injury are of importance for multicenter studies and have seldom been studied.

OBJECTIVE

To quantify the differences in centers enrolling patients in randomized clinical trials (RCTs) and surveys.

METHODS

We analyzed individual patient data from 9578 patients with moderate and severe traumatic brain injury enrolled in 10 RCTs and 3 observational studies. We used random-effects logistic regression models to estimate the between-center differences in unfavorable outcome (dead, vegetative state, or severe disability measured with the Glasgow Outcome Scale) at 6 months adjusted for differences in patient characteristics. We calculated the difference in odds of unfavorable outcome between the centers at the higher end vs those at the lower end of the outcome distribution. We analyzed the total database, Europe and the United States separately, and 4 larger RCTs.

RESULTS

The 9578 patients were enrolled at 265 centers, and 4629 (48%) had an unfavorable outcome. After adjustment for patient characteristics, there was a 3.3-fold difference in the odds of unfavorable outcome between the centers at the lower end of the outcome distribution (2.5th percentile) vs those at the higher end of the outcome distribution (97.5th percentile; P<.001). In the 4 larger RCTs, the differences between centers were similar. However, differences were smaller between centers in the United States (2.4-fold) than between centers in Europe (3.8-fold).

CONCLUSION

Outcome after traumatic brain injury differs substantially between centers, particularly in Europe. Further research is needed to study explanations for these differences to suggest where quality of care might be improved.

Impact of abciximab in elderly patients with high-risk acute coronary syndrome undergoing percutaneous coronary intervention: an observational registry study

BACKGROUND

An increasing proportion of patients with acute coronary syndrome (ACS) requiring percutaneous coronary intervention (PCI) are classified as elderly (aged ≥70 years). The glycoprotein IIb/IIIa inhibitor abciximab is known to reduce adverse outcomes in patients aged <70 years with high-risk ACS undergoing PCI, but conflicting findings relating to its effects in the elderly have been reported.

OBJECTIVE

The aim of this study was to evaluate the effect of abciximab in elderly high-risk ACS patients undergoing PCI.

METHODS

From our dedicated PCI registry we identified 2068 ACS patients with high-risk lesions that were treated with PCI. Baseline data were collected prospectively. All-cause mortality, target vessel revascularization (TVR), myocardial infarction (MI), and the combination of these were primary study endpoints. All endpoints within 1 year after PCI were registered and validated. The population was subsequently stratified according to age and use of abciximab.

RESULTS

Elderly patients constituted 42% of the total population. They presented with more co-morbidities, were less frequently treated with abciximab and had a higher risk of reaching the combined endpoint and higher all-cause mortality than younger patients. The age/abciximab stratified analysis revealed no effect of abciximab on any of the endpoints in elderly patients (combined endpoint: no abciximab 22.6% vs abciximab 23.4%, p=0.85; all-cause mortality: no abciximab 15.4% vs abciximab 15.9%, p=0.91; TVR: no abciximab 3.4% vs abciximab 5.5%, p=0.21; MI: no abciximab 7.0% vs abciximab 8.5%, p=0.54), whereas all-cause mortality and the risk of reaching the combined endpoint were significantly reduced in younger patients (combined endpoint: no abciximab 14.0% vs abciximab 9.4%, p=0.03; all-cause mortality: no abciximab 4.5% vs abciximab 1.7%, p=0.02; TVR: no abciximab 5.5% vs abciximab 4.3%, p=0.39; MI: no abciximab 7.2% vs abciximab 6.6%, p=0.80). These findings were confirmed in our adjusted analyses.

CONCLUSIONS

In this large observational study we found no benefit of abciximab treatment in elderly high-risk ACS patients who underwent PCI. These findings should be taken into consideration when deciding on the treatment strategy for elderly ACS patients undergoing PCI.

Mortality and revascularization following admission for acute myocardial infarction: implication for rural veterans

INTRODUCTION

Annually, over 3,000 rural veterans are admitted to Veterans Health Administration (VA) hospitals for acute myocardial infarction (AMI), yet no studies of AMI have utilized the VA rural definition.

METHODS

This retrospective cohort study identified 15,870 patients admitted for AMI to all VA hospitals. Rural residence was identified by either Rural-Urban Commuting Area (RUCA) codes or the VA Urban/Rural/Highly Rural (URH) system. Endpoints of mortality and coronary revascularization were adjusted using administrative laboratory and clinical variables.

RESULTS

URH codes identified 184 (1%) veterans as highly rural, 6,046 (39%) as rural, and 9,378 (60%) as urban; RUCA codes identified 1,350 (9%) veterans from an isolated town, 3,505 (22%) from a small or large town, and 10,345 (65%) from urban areas. Adjusted mortality analyses demonstrated similar risk of mortality for rural veterans using either URH or RUCA systems. Hazards of revascularization using the URH classification demonstrated no difference for rural (HR, 0.96; 95% CI, 0.94-1.00) and highly rural veterans (HR, 1.13; 0.96-1.31) relative to urban veterans. In contrast, rural (relative to urban) veterans designated by the RUCA system had lower rates of revascularization; this was true for veterans from small or large towns (HR, 0.89; 0.83-0.95) as well as veterans from isolated towns (HR, 0.86; 0.78-0.93).

CONCLUSION

Rural veterans admitted for AMI care have a similar risk of 30-day mortality but the adjusted hazard for receipt of revascularization for rural veterans was dependent upon the rural classification system utilized. These findings suggest potentially lower rates of revascularization for rural veterans.

Development of a Medicaid behavioral health case-mix model

Many Medicaid programs have either fully or partially carved out mental health services. The evaluation of carved out plans requires a case-mix model that accounts for differing health status across Medicaid managed care plans. This article develops a diagnosis-based case-mix adjustment system specific to Medicaid behavioral health care. Several different model specifications are compared that use untransformed, square root transformed, and log-transformed expenditures.

Acute coronary syndromes: Diagnosis and management, part II

At the most severe end of the spectrum of acute coronary syndromes is ST-segment elevation myocardial infarction (STEMI), which usually occurs when a fibrin-rich thrombus completely occludes an epicardial coronary artery. The diagnosis of STEMI is based on clinical characteristics and persistent ST-segment elevation as demonstrated by 12-lead electrocardiography. Patients with STEMI should undergo rapid assessment for reperfusion therapy, and a reperfusion strategy should be implemented promptly after the patient's contact with the health care system. Two methods are currently available for establishing timely coronary reperfusion: primary percutaneous coronary intervention and fibrinolytic therapy. Percutaneous coronary intervention is the preferred method but is not always available. Antiplatelet agents and anticoagulants are critical adjuncts to reperfusion. This article summarizes the current evidence-based guidelines for the diagnosis and management of STEMI. This summary is followed by a brief discussion of the role of noninvasive stress testing in the assessment of patients with acute coronary syndrome and their selection for coronary revascularization.

Development and validation of a risk-adjustment tool in acute asthma

OBJECTIVE

To develop and prospectively validate a risk-adjustment tool in acute asthma.

DATA SOURCES

Data were obtained from two large studies on acute asthma, the Multicenter Airway Research Collaboration (MARC) and the National Emergency Department Safety Study (NEDSS) cohorts. Both studies involved >60 emergency departments (EDs) and were performed during 1996-2001 and 2003-2006, respectively. Both included patients aged 18-54 years presenting to the ED with acute asthma.

STUDY DESIGN

Retrospective cohort studies.

DATA COLLECTION

Clinical information was obtained from medical record review. The risk index was derived in the MARC cohort and then was prospectively validated in the NEDSS cohort.

PRINCIPLE FINDINGS

There were 3,515 patients in the derivation cohort and 3,986 in the validation cohort. The risk index included nine variables (age, sex, current smoker, ever admitted for asthma, ever intubated for asthma, duration of symptoms, respiratory rate, peak expiratory flow, and number of beta-agonist treatments) and showed satisfactory discrimination (area under the receiver operating characteristic curve, 0.75) and calibration ( p=.30 for Hosmer-Lemeshow test) when applied to the validation cohort.

CONCLUSIONS

We developed and validated a novel risk-adjustment tool in acute asthma. This tool can be used for health care provider profiling to identify outliers for quality improvement purposes.

Combination Therapy Improves Survival After Acute Myocardial Infarction in the Elderly with Chronic Kidney Disease

BACKGROUND

Individuals with chronic kidney disease have a high mortality rate after acute myocardial infarction. It is not known how frequently these individuals are prescribed combination cardioprotective therapy and if survival is affected by such therapy after acute myocardial infarction.

METHODS

A retrospective cohort study of 1,342 Medicare recipients with acute myocardial infarction. Data were collected by medical chart abstraction as part of the Cooperative Cardiovascular Project in 60 hospitals in North Carolina during 5/30/1996-12/28/1997. We categorized cardioprotective medication use as aspirin alone, aspirin with beta-blockers, and aspirin with beta-blockers and ace-inhibitors. Chronic kidney disease was defined as a derived glomerular filtration rate (GFR) ranging from 15-89 mL/min/1.73 m2. Cox proportional hazards regression analyses were performed to determine the effect of cardioprotective medication use on survival while controlling for potential explanatory variables.

RESULTS

The prevalence of cardioprotective medication use differed among levels of chronic kidney disease. Those with severe kidney disease (GFR 15-29 mL/min/1.73 m2) were less frequently prescribed aspirin with beta-blockers, 27.1%, and only 8.6% were prescribed aspirin with beta-blockers and ace-inhibitors. Survival was improved with prescribed cardioprotective medication use. In severe kidney disease (GFR 15-29 mL/min/1.73 m2), the hazards risk for death was 0.21 (0.08, 0.53) for aspirin alone, 0.17 (0.06, 0.51) for aspirin with beta-blockers, and 0.35 (0.09, 1.42) for aspirin with beta-blockers and ace-inhibitors.

CONCLUSIONS

Individuals with chronic kidney disease benefit from combination cardioprotective therapy, but are less likely to be prescribed them after acute myocardial infarction. Further investigation is warranted to identify possible reasons for these observed treatment disparities.

Explicit risk in acute coronary syndrome management

At least implicitly, most clinical decisions represent an integration of disease and treatment-based risk assessments. Often, as is the case with acute coronary syndrome (ACS), these decisions need to be made quickly at a time when data elements are limited, and published risk models are very useful in clarifying time-dependent determinants of risk. The present review emphasizes the value of explicit risk assessment and reinforces the fact that patients at highest risk are often those most likely to benefit from newer and more invasive therapies. Suggested ways to incorporate published ACS risk models into clinical practice are included. In addition, the need to adopt a longer-term view of risk in ACS patients is stressed, with particular regard to the important role of heart failure prediction and treatment.

Does interhospital transfer improve outcome of acute myocardial infarction? A propensity score analysis from the Cardiovascular Cooperative Project

BACKGROUND

Many patients suffering acute myocardial infarction (AMI) are transferred from one hospital to another during their hospitalization. There is little information about the outcomes related to interhospital transfer. The purpose of this study was to compare processes and outcomes of AMI care among patients undergoing interhospital transfer with special attention to the impact on mortality in rural hospitals.

METHODS

National sample of Medicare patients in the Cooperative Cardiovascular Study (n = 184,295). Retrospective structured medical record review of AMI hospitalizations. Descriptive study using a retrospective propensity score analysis of clinical and administrative data for 184,295 Medicare patients admitted with clinically confirmed AMI to 4,765 hospitals between February 1994 and July 1995. Main outcome measure included: 30-day mortality, administration of aspirin, beta-blockers, ACE-inhibitors, and thrombolytic therapy.

RESULTS

Overall, 51,530 (28%) patients underwent interhospital transfer. Transferred patients were significantly younger, less critically ill, and had lower comorbidity than non-transferred patients. After propensity-matching, patients who underwent interhospital transfer had better quality of care anlower mortality than non-transferred patients. Patients cared for in a rural hospital had similar mortality as patients cared for in an urban hospital.

CONCLUSION

Transferred patients were vastly different than non-transferred patients. However, even after a rigorous propensity-score analysis, transferred patients had lower mortality than non-transferred patients. Mortality was similar in rural and urban hospitals. Identifying patients who derive the greatest benefit from transfer may help physicians faced with the complex decision of whether to transfer a patient suffering an acute MI.

Socioeconomic disparities in outcomes after acute myocardial infarction

BACKGROUND

Patients of low socioeconomic status (SES) have higher mortality after acute myocardial infarction (AMI). Little is known about the underlying mechanisms or the relationship between SES and rehospitalization after AMI.

METHODS

We analyzed data from the PREMIER observational study, which included 2142 patients hospitalized with AMI from 18 US hospitals. Socioeconomic status was measured by self-reported household income and education level. Sequential multivariable modeling assessed the relationship of socioeconomic factors with 1-year all-cause mortality and all-cause rehospitalization after adjustment for demographics, clinical factors, and quality-of-care measures.

RESULTS

Both household income and education level were associated with higher risk of mortality (hazard ratio 2.80, 95% CI 1.37-5.72, lowest to highest income group) and rehospitalization after AMI (hazard ratio 1.55, 95% CI 1.17-2.05). Patients with low SES had worse clinical status at admission and received poorer quality of care. In multivariable modeling, the relationship between household income and mortality was attenuated by adjustment for demographic and clinical factors (hazard ratio 1.19, 95% CI 0.54-2.62), with a further small decrement in the hazard ratio after adjustment for quality of care. The relationship between income and rehospitalization was only partly attenuated by demographic and clinical factors (hazard ratio 1.38, 95% CI 1.01-1.89) and was not influenced by adjustment for quality of care.

CONCLUSIONS

Patients' baseline clinical status largely explained the relationship between SES and mortality, but not rehospitalization, among patients with AMI.

Prediction of risk of death and myocardial infarction in the six months after presentation with acute coronary syndrome: prospective multinational observational study (GRACE)

OBJECTIVE

To develop a clinical risk prediction tool for estimating the cumulative six month risk of death and death or myocardial infarction to facilitate triage and management of patients with acute coronary syndrome.

DESIGN

Prospective multinational observational study in which we used multivariable regression to develop a final predictive model, with prospective and external validation.

SETTING

Ninety four hospitals in 14 countries in Europe, North and South America, Australia, and New Zealand.

POPULATION

43,810 patients (21,688 in derivation set; 22,122 in validation set) presenting with acute coronary syndrome with or without ST segment elevation enrolled in the global registry of acute coronary events (GRACE) study between April 1999 and September 2005.

MAIN OUTCOME MEASURES

Death and myocardial infarction.

RESULTS

1989 patients died in hospital, 1466 died between discharge and six month follow-up, and 2793 sustained a new non-fatal myocardial infarction. Nine factors independently predicted death and the combined end point of death or myocardial infarction in the period from admission to six months after discharge: age, development (or history) of heart failure, peripheral vascular disease, systolic blood pressure, Killip class, initial serum creatinine concentration, elevated initial cardiac markers, cardiac arrest on admission, and ST segment deviation. The simplified model was robust, with prospectively validated C-statistics of 0.81 for predicting death and 0.73 for death or myocardial infarction from admission to six months after discharge. The external applicability of the model was validated in the dataset from GUSTO IIb (global use of strategies to open occluded coronary arteries).

CONCLUSIONS

This risk prediction tool uses readily identifiable variables to provide robust prediction of the cumulative six month risk of death or myocardial infarction. It is a rapid and widely applicable method for assessing cardiovascular risk to complement clinical assessment and can guide patient triage and management across the spectrum of patients with acute coronary syndrome.

Present-at-admission diagnoses improved mortality risk adjustment among acute myocardial infarction patients

OBJECTIVE

Hospital mortality outcomes for acute myocardial infarction (AMI) patients are a focus of quality improvement programs conducted by government agencies. AMI mortality risk-adjustment models using administrative data typically adjust for baseline differences in mortality risk with a limited set of common and definite comorbidities. In this study, we present an AMI mortality risk-adjustment model that adjusts for comorbid disease and for AMI severity using information from secondary diagnoses reported as present at admission for California hospital patients.

STUDY DESIGN AND SETTING

AMI patients were selected from California hospital administrative data for 1996 through 1999 according to criteria used by the California Hospital Outcomes Project Report on Heart Attack Outcomes, a state-mandated public report that compares hospital mortality outcomes. We compared results for the new model to two mortality risk-adjustment models used to assess hospital AMI mortality outcomes by the state of California, and to two other models used in prior research.

RESULTS

The model using present-at-admission diagnoses obtained substantially better discrimination between predicted survival and inpatient death than the other models we considered.

CONCLUSION

AMI mortality risk-adjustment methods can be meaningfully improved using present-at-admission diagnoses to identify comorbid disease and conditions related closely to AMI.

Acute, severe noncardiac conditions in patients with acute myocardial infarction

PURPOSE

The study's purpose was to determine the prevalence and prognostic importance of acute, severe, noncardiac conditions present at the time of an acute myocardial infarction (AMI).

METHODS

We identified consecutive patients with AMI who were discharged from Yale-New Haven Hospital between January 1, 1997, and June 30, 2000. Acute, noncardiac conditions that were present at admission were abstracted from patient records and graded by severity (imminent threat to life; other significant condition that would warrant admission). We examined the prognostic importance of these conditions on hospital mortality in multivariable logistic models. The study included 1145 patients with AMI, of whom 8.5% (n=97) presented with an acute, life-threatening, noncardiac condition at admission and 19.5% (n=223) presented with another significant noncardiac condition.

RESULTS

Hospital mortality was 25.8% and 9.0%, respectively, for patients who presented with life-threatening and other significant noncardiac conditions, compared with 4.6% for patients without either of these conditions. In multivariable analysis, life-threatening noncardiac conditions were associated with increased hospital mortality after adjusting for demographic factors, medical history, clinical presentation, cardiac severity, and initial therapy (odds ratio 2.5; 95% confidence interval [CI], 1.2-5.2). No increased hospital mortality risk was found for other significant noncardiac conditions in the risk-adjusted analyses (odds ratio 1.0; 95% CI, 0.5-1.7).

CONCLUSIONS

A subgroup of patients with AMI presented with a life-threatening noncardiac condition, which was associated with a marked increase in the risk of death during the hospitalization. Despite the excessive mortality risk associated with concomitant noncardiac conditions, this subset of patients with AMI are poorly described in current literature.

Clinical laboratory findings associated with in-hospital mortality

The diagnostic approach and the clinical management of critically ill patients is challenging. The recognition of biomarkers related to in-hospital mortality is of importance for identification of patients at increased risk of death. Many prediction models assessing the severity of illness and likelihood of hospital survival were developed using logistic regression analyses. These models include several laboratory parameters, such as white blood cell counts, serum bilirubin, serum albumin, blood glucose, serum electrolytes and markers which reflect acid-base disturbances. Recently, several other biomarkers, including troponin, B-type natriuretic peptide (BNP), N-terminal proBNP, C-reactive protein, procalcitonin, cholesterol and coagulation related markers have emerged as clinically useful tools for risk stratification and mortality prediction of heterogeneous and more specific subgroups of critically ill patients. More investigations are required to verify whether risk stratification based on mortality-related biomarkers may translate into targeted treatment strategies to improve clinical outcome of the critical illness. Biomarkers which are related to in-hospital mortality are highlighted in the current review.