Determinants of cardiac catheterization use in older Medicare patients with acute myocardial infarction

Hospital-Level Variation in Ticagrelor Use in Patients With Acute Coronary Syndrome

Background

Despite improved outcomes associated with ticagrelor compared with clopidogrel in acute coronary syndrome (ACS), many studies have demonstrated slow adoption of ticagrelor in the United States because of its increased cost. Less is known about how ticagrelor is adopted when there is no added cost consideration. Our objectives were to determine patterns of use of ticagrelor, hospital‐level adoption of ticagrelor use, and factors associated with its use after ACS in a publicly funded health care system.

Methods and Results

We conducted a population‐based cohort study including patients (≥65 years) hospitalized with their first ACS from April 2014 to March 2018 in Ontario, Canada. We determined temporal trends in ticagrelor use and hospital‐level adoption of its use post‐ACS discharge. Using hierarchical regression models, we identified significant predictors of ticagrelor use. There were 23 962 patients with ACS (mean age 76.3 years, 59.7% men) hospitalized in 156 hospitals. Overall ticagrelor use increased from 32.6% in 2014/2015 to 51.8% in 2017/2018. There was substantial variation in ticagrelor use post‐ACS across hospitals, with hospital‐specific prescribing rates ranging from 0% to 83.6%. Lower odds of ticagrelor use was associated with advanced age and the presence of comorbidities. Besides patient factors, being admitted to a rurally located hospital more than halved the odds of being prescribed ticagrelor (odds ratio [OR], 0.49; 95% CI, 0.32–0.77). Being managed by a cardiologist during the index ACS hospitalization was associated with higher odds of having a ticagrelor prescription after ACS (OR, 2.80; 95% CI, 2.36–3.33).

Conclusions

Ticagrelor use rates varied substantially across hospitals and were strongly associated with physician and hospital factors independent of patient characteristics.

Trends in the magnitude of chronic conditions in patients hospitalized with a first acute myocardial infarction

Background:

Among adults with heart disease, there is a high prevalence of concomitant chronic medical conditions. We studied patients with a first acute myocardial infarction to describe: sample population characteristics; trends of the most prevalent pairs of chronic conditions; and differences in hospital management according to burden of these morbidities.

Methods and Results:

Patients (n = 1,564) hospitalized with an incident AMI at the 3 major medical centers in central Massachusetts during 2005, 2011, and 2015 comprised the study population. Hospital medical records were reviewed to identify 11 more prevalent chronic conditions. The median age of this population was 68 years and 56% were men. The median number of previously diagnosed chronic conditions was 2. Patients hospitalized during 2015 were more likely to be younger than those hospitalized in the earliest study cohorts. The most common pairs of chronic conditions for those hospitalized in 2005 were: anemia-chronic kidney disease (31%), chronic kidney disease-heart failure (30%), and stroke-atrial fibrillation (27%). Among patients hospitalized during 2011, chronic kidney disease-heart failure (29%), hypertension-hyperlipidemia (27%), and hypertension-diabetes (27%) were the most common pairs whereas hypertension-hyperlipidemia (43%), diabetes-heart failure (30%), and chronic kidney disease-diabetes (23%) were the most frequent pairs recorded in 2015. There was a significant decrease in the odds of undergoing cardiac catheterization and a percutaneous coronary intervention in those with higher chronic disease burden in the most recent as compared to earliest study years.

Conclusions:

Our findings highlight the magnitude of chronic conditions in patients with AMI and the challenges of caring for this vulnerable population.

Does renal function affect the efficacy or safety of a pharmacoinvasive strategy in patients with ST-elevation myocardial infarction? A meta-analysis

BACKGROUND

The efficacy and safety of pharmacoinvasive strategy following fibrinolysis for ST-elevation myocardial infarction (STEMI) in relation to renal function have not been established.

METHODS

Using patient-level data from 4 randomized controlled trials, we examined the efficacy and safety of pharmacoinvasive versus standard treatment after fibrinolysis for STEMI. Patients were stratified based on the estimated glomerular filtration rate (eGFR) on presentation (<60 mL/min/1.73 m² vs ≥60 mL/min/1.73 m²). The primary outcome was the composite of death or reinfarction at 30 days.

RESULTS

Of 2,029 patients, 457 (23%) had an eGFR<60 mL/min/1.73 m². Patients with eGFR<60 mL/min/1.73 m² were older and had higher Thrombolysis in Myocardial Infarction risk scores. Compared with patients with eGFR≥60 mL/min/1.73 m², patients with renal dysfunction had higher rates of the primary outcome (5.3% vs 11.8%, respectively; P<.001). There was no significant heterogeneity in the treatment effect of pharmacoinvasive strategy on the primary outcome (P heterogeneity=.73) or the rate of death or reinfarction at 1 year (P heterogeneity=.64) in relation to eGFR. Patients with renal dysfunction had higher rates of in-hospital major bleeding compared with patients with eGFR ≥60 mL/min/1.73 m² (7.7% vs 4.3%, respectively; P=.004); however, there was no difference in bleeding events between treatment arms in the overall cohort or in relation to eGFR (P heterogeneity=.67).

CONCLUSIONS

Renal impairment is associated with increased rates of adverse events in STEMI patients treated with fibrinolysis. However, the safety and efficacy of pharmacoinvasive strategy are preserved in patients with renal impairment on presentation.

Determinants of invasive strategy in elderly patients with non-ST elevation myocardial infarction

Background

Knowledge gaps across literature prevent current guidelines from providing the profile of elderly patients most likely to derive benefit from invasive strategy (IS) in non ST-elevation myocardial infarction (NSTEMI). Furthermore, the benefit of IS in a real-world elderly population with NSTEMI remains unclear. The aims of this study were to determine factors that lead the cardiologist to opt for an IS in elderly patients with NSTEMI, and to assess the impact of IS on the 6-month all-cause mortality.

Methods

This multicenter prospective study enrolled all consecutive patients aged ≥ 75 years old who presented a NSTEMI and were hospitalized in cardiology intensive care unit between February 2014 and February 2015. Patients were compared on the basis of reperfusion strategy (invasive or conservative) and living status at six months, in order to determine multivariate predictors of the realization of an IS and multivariate predictors of 6-month mortality.

Results

A total of 141 patients were included; 87 (62%) underwent an IS. The strongest independent determinants of IS were younger age [odds ratio (OR): 0.85, 95%-confidence interval (CI): 0.78–0.92; P < 0.001) and lower “Cumulative Illness Rating Scale-Geriatric” number of categories score (OR: 0.83, 95%CI: 0.73–0.95; P = 0.002). IS was not significantly associated with 6-month survival (OR: 0.80, 95%CI: 0.27–2.38; P = 0.69).

Conclusions

In real-world elderly patients with NSTEMI, younger patients with fewer comorbidities profited more often from an IS. However, IS did not modify 6-month all-cause mortality.

Race/Ethnicity and overuse of care: a systematic review

POLICY POINTS: Racial/ethnic differences in the overuse of care (specifically, unneeded care that does not improve patients' outcomes) have received little scholarly attention. Our systematic review of the literature (59 studies) found that the overuse of care is not invariably associated with race/ethnicity, but when it was, a substantial proportion of studies found greater overuse of care among white patients. The absence of established subject terms in PubMed for the overuse of care or inappropriate care impedes the ability of researchers or policymakers to synthesize prior scientific or policy efforts.

CONTEXT

The literature on disparities in health care has examined the contrast between white patients receiving needed care, compared with racial/ethnic minority patients not receiving needed care. Racial/ethnic differences in the overuse of care, that is, unneeded care that does not improve patients' outcomes, have received less attention. We systematically reviewed the literature regarding race/ethnicity and the overuse of care.

METHODS

We searched the Medline database for US studies that included at least 2 racial/ethnic groups and that examined the association between race/ethnicity and the overuse of procedures, diagnostic (care) or therapeutic care. In a recent review, we identified studies of overuse by race/ethnicity, and we also examined reference lists of retrieved articles. We then abstracted and evaluated this information, including the population studied, data source, sample size and assembly, type of care, guideline or appropriateness standard, controls for clinical confounding and financing of care, and findings.

FINDINGS

We identified 59 unique studies, of which 11 had a low risk of methodological bias. Studies with multiple outcomes were counted more than once; collectively they assessed 74 different outcomes. Thirty-two studies, 6 with low risks of bias (LRoB), provided evidence that whites received more inappropriate or nonrecommended care than racial/ethnic minorities did. Nine studies (2 LRoB) found evidence of more overuse of care by minorities than by whites. Thirty-three studies (6 LRoB) found no relationship between race/ethnicity and overuse.

CONCLUSIONS

Although the overuse of care is not invariably associated with race/ethnicity, when it was, a substantial proportion of studies found greater overuse of care among white patients. Clinicians and researchers should try to understand how and why race/ethnicity might be associated with overuse and to intervene to reduce it.

Relationship between care gaps and projected life expectancy after acute myocardial infarction

BACKGROUND

Higher-risk patients may not receive evidence-based therapy because of limited life expectancy, which is a composite measure that encompasses many patient factors, including age, frailty, and comorbidities. In this study, we evaluated the extent to which treatment care gaps can be explained by a difference in projected life expectancy.

METHODS AND RESULTS

An observational cohort study was conducted on acute myocardial infarction patients hospitalized in Ontario, Canada. Projected life expectancy was estimated using actual survival data with extrapolation using proportional hazard models adjusting for important covariates. The relationship between projected life expectancy with statins and reperfusion therapy was examined using generalized linear models. Among the 7001 acute myocardial infarction patients, 84.3% were prescribed statins and 72.9% were treated with reperfusion therapy. When projected life expectancy was <10 years, the likelihood of receiving either treatment declined progressively with reduction in life expectancy (P<0.001). At the 25th percentile of projected life expectancies, the likelihood of receiving a statin decreased by 1.4% (95% confidence interval, 1.0-1.8%), and acute reperfusion therapy decreased by 2.6% (95% confidence interval, 1.8-3.3%) for each year decline in projected life expectancy.

CONCLUSIONS

Life expectancy of a patient strongly influences evidence-based treatment in acute myocardial infarction. It was seen not only among patients with limited life expectancies but also among those with many years to live. Treatment care gaps may reflect clinicians' synthesis about frailty and life-expectancy gains.

Regional density of cardiologists and rates of mortality for acute myocardial infarction and heart failure

BACKGROUND

Cardiologists are distributed unevenly across regions of the United States. It is unknown whether patients in regions with fewer cardiologists have worse outcomes after hospitalization for acute myocardial infarction (AMI) or heart failure (HF).

METHODS AND RESULTS

Using Medicare administrative claims data from 2010, we examined the relationship between regional density of cardiologists and risk of death after hospitalization for AMI and HF using hospitalizations for pneumonia as a comparison. We defined density as the number of cardiologists divided by population aged≥65 years within hospital referral regions, categorized into quintiles. Among 171 126 admissions for AMI, 352 853 admissions for HF, and 343 053 admissions for pneumonia, we tested associations between density of cardiologists and 30-day and 1-year mortality for each condition. We used 2-level hierarchical logistic regression models that adjusted for characteristics of patients and hospital referral regions. Patients hospitalized for AMI (odds ratios [OR], 1.13; 95% confidence interval [CI], 1.06-1.21) and HF (OR, 1.19; 95% CI, 1.12-1.27) in the lowest quintile of density had modestly higher 30-day mortality risk compared with patients in the highest quintile, unlike patients hospitalized for pneumonia (OR, 1.02; 95% CI, 0.96-1.09). Patients hospitalized for AMI (OR, 1.06; 95% CI, 1.00-1.12) and HF (OR, 1.09; 95% CI, 1.04-1.13) in the lowest quintile had slightly higher 1-year mortality risk, unlike patients hospitalized for pneumonia (OR, 1.00; 95% CI, 0.95-1.05).

CONCLUSIONS

Patients hospitalized for AMI and HF in regions with a low density of cardiologists experienced modestly higher 30-day and 1-year mortality risk, unlike patients with pneumonia.

External adjustment sensitivity analysis for unmeasured confounding: an application to coronary stent outcomes, Pennsylvania 2004-2008

BACKGROUND

Assessing the real-world comparative effectiveness of common interventions is challenged by unmeasured confounding.

OBJECTIVE

To determine whether the mortality benefit shown for drug-eluting stents (DES) over bare metal stents (BMS) in observational studies persists after controls for/tests for confounding.

DATA SOURCES/STUDY SETTING

Retrospective observational study involving 38,019 patients, 65 years or older admitted for an index percutaneous coronary intervention receiving DES or BMS in Pennsylvania in 2004-2005 followed up for death through 3 years.

STUDY DESIGN

Analysis was at the patient level. Mortality was analyzed with Cox proportional hazards models allowing for stratification by disease severity or DES use propensity, accounting for clustering of patients. Instrumental variables analysis used lagged physician stent usage to proxy for the focal stent type decision. A method originating in work by Cornfield and others in 1954 and popularized by Greenland in 1996 was used to assess robustness to confounding.

PRINCIPAL FINDINGS

DES was associated with a significantly lower adjusted risk of death at 3 years in Cox and in instrumented analyses. An implausibly strong hypothetical unobserved confounder would be required to fully explain these results.

CONCLUSIONS

Confounding by indication can bias observational studies. No strong evidence of such selection biases was found in the reduced risk of death among elderly patients receiving DES instead of BMS in a Pennsylvanian state-wide population.

Most important outcomes research papers in cardiovascular disease in the elderly

The following are highlights from the new series, Circulation: Cardiovascular Quality and Outcomes Topic Review. This series will summarize the most important manuscripts, as selected by the Editor, that have published in the Circulation portfolio. The objective of this new series is to provide our readership with a timely, comprehensive selection of important papers that are relevant to the quality and outcomes and general cardiology audience. The studies included in this article represent the most significant research in the area of cardiovascular disease in the elderly.