Modifiable factors associated with sleep dysfunction in adults with heart failure

BACKGROUND

Sleep dysfunction contributes to poor quality of life in adults with heart failure (HF). The purpose of this study was to identify factors associated with sleep dysfunction that may be modifiable.

METHODS

Data were collected from 266 subjects enrolled from three sites in the U.S. Sleep dysfunction was measured over the past month with the Pittsburgh sleep quality index, using a score > 10 to indicate sleep dysfunction. Potentially modifiable clinical, behavioral, and psychological factors thought to be associated with sleep dysfunction were analyzed with hierarchical logistic regression analysis.

RESULTS

When covariates of age, gender, race, data collection site, and New York Heart Association (NYHA) functional class were entered on the first step, only NYHA was a significant correlate of sleep dysfunction. When the clinical, behavioral, and psychological factors were entered, correlates of sleep dysfunction were the number of drugs known to cause daytime somnolence (OR = 2.08), depression (OR = 1.83), worse overall perceived health (OR = 1.64), and better sleep hygiene (OR = 1.40). Although most (54%) subjects had sleep disordered breathing (SDB), SDB was not a significant predictor of sleep dysfunction.

DISCUSSION

Factors associated with sleep dysfunction in HF include medications with sleepiness as a side-effect, depression, poorer health perceptions, and better sleep hygiene. Sleep dysfunction may motivate HF patients to address sleep hygiene. Eliminating medications with sleepiness as a side-effect, treating depression and perceptions of poor health may improve sleep quality in HF patients.

Patterns of warfarin use and subsequent outcomes in atrial fibrillation in primary care practices

BACKGROUND

Warfarin is recommended for stroke prevention in high-risk patients with atrial fibrillation. However, it is often underutilized and inadequately managed in actual clinical practice.

OBJECTIVES

To examine the patterns of warfarin use and their relationship with stroke and bleeding in atrial fibrillation patients in community-based primary care practices.

DESIGN

Retrospective longitudinal cohort study.

PARTICIPANTS

A total of 1141 atrial fibrillation patients were selected from 17 primary care practices with a shared electronic medical record and characterized by stroke risk, potential barriers to anticoagulation, and comorbid conditions.

MAIN MEASURES

Duration and number of warfarin exposures, interruptions in warfarin exposure > 45 days, stroke, and bleeding events.

RESULTS

Among 1141 patients with a mean age of 70 years (standard deviation 13.3) and mean follow-up of 3.4 years (standard deviation 3.0), 764 (67%) were treated with warfarin. Warfarin was discontinued within 1 year in 194 (25.4%), and 349 (45.7%) remained on warfarin at the end of follow-up. Interruptions in warfarin use were common, occurring in 32.6% (249 of 764) of patients. Those with two or more interruptions were younger and at lower baseline stroke risk when compared to those with no interruptions. There were 76 first strokes and 73 first-bleeding events in the follow-up period. When adjusted for baseline stroke risk, time to warfarin start, and total exposure time, two or more interruptions in warfarin use was associated with an increased risk of stroke (relative risk, 2.29; 95% confidence interval: 1.29-4.07). There was no significant association between warfarin interruptions and bleeding events.

CONCLUSION

Warfarin was underutilized in a substantial portion of eligible atrial fibrillation patients in these community-based practices. In addition, prolonged interruptions in anticoagulation were common in this population, and multiple interruptions were associated with over twice the risk of stroke when compared to those treated continuously.

Cost of Heart Failure in Patients Receiving beta-Blockers and Angiotensin-Converting Enzyme Inhibitors

OBJECTIVE

Numerous studies support the benefit of beta-blockers and angiotensin-converting enzyme inhibition (ACE-I) in the management of heart failure. However, the real-world cost of heart failure in patients who take these medications is not well documented; furthermore, it is unclear if heart failure costs remain significant when current, appropriately aggressive care is delivered.

DESIGN

This study describes 1-year medical costs in patients hospitalised for heart failure who received these therapies, alone or in combination.

METHODS

The study population was derived from 2.5 million patients with at least 3 years' continuous eligibility in Pharmetrics((R)), an integrated claims and pharmacy database on approximately 25 million covered lives from 40 US health plans. The enrolment period was from 1 January 1996 to 31 December 2000. Costs included all recorded payments over a 1-year period. A total of 3073 patients (age >18 years) hospitalised with heart failure were identified (mean [+/- SD] age 72 +/- 13 years; 46% female).

RESULTS

The 1-year cost was $US16 786 in patients who received neither ACE inhibitors nor beta-blockers as compared with $US19 567, $US22 785 and $US27 078 in patients who received ACE inhibitors, beta-blockers or both drugs at maximum dosage, respectively (p < 0.001) [year of costing 2000]. Follow-up costs were substantial, representing almost twice the initial hospitalisation cost. Adjusted for age, sex, diabetes mellitus, coronary disease, hypertension and renal failure, costs remained significant in heart failure patients who received ACE inhibitors and/or beta-blockers.

CONCLUSIONS

The 1-year cost of therapy for patients with heart failure is substantial, and there remains considerable need for more effective therapy to reduce the societal economic burden.

What is the best measure of daytime sleepiness in adults with heart failure?

PURPOSE

To identify the best screening measure of daytime sleepiness in adults with heart failure (HF).

DATA SOURCES

A total of 280 adults with HF completed the Epworth Sleepiness Scale, the Stanford Sleepiness Scale, and a single Likert item measuring daytime sleepiness. The sensitivity and specificity of these self-report measures were assessed in relation to a measure of daytime dysfunction from poor sleep quality.

CONCLUSIONS

Only 16% of the sample reported significant daytime dysfunction because of poor sleep quality. Those reporting daytime dysfunction were likely to be younger (p < .001), to be unmarried (p = .002), to have New York Heart Association (NYHA) functional class IV HF (p = .015), and to report low income (p = .006) and fewer hours of sleep (p = .015). The measure of daytime sleepiness that was most sensitive to daytime dysfunction was a single Likert item measured on a 10-point (1-10) scale. Patients with a score ≥4 were 2.4 times more likely to have daytime dysfunction than those with a score <4.

IMPLICATIONS FOR PRACTICE

Complaints of daytime dysfunction because of poor sleep are not common in adults with HF. Routine use of a single question about daytime sleepiness can help nurse practitioners to identify those HF patients with significant sleep issues that may require further screening.

Baseline stress myocardial perfusion imaging results and outcomes in patients with stable ischemic heart disease randomized to optimal medical therapy with or without percutaneous coronary intervention

BACKGROUND

The COURAGE trial reported similar clinical outcomes for patients with stable ischemic heart disease (SIHD) receiving optimal medical therapy (OMT) with or without percutaneous coronary intervention (PCI). The current post hoc substudy analysis examined the relationship between baseline stress myocardial ischemia and clinical outcomes based on randomized treatment assignment.

METHODS

A total of 1,381 randomized patients (OMT n = 699, PCI + OMT n = 682) underwent baseline stress myocardial perfusion single-photon emission computed tomographic imaging. Site investigators interpreted the extent of ischemia by the number of ischemic segments using a 6-segment myocardial model. Patients were divided into those with no to mild (<3 ischemic segments) and moderate to severe ischemia (≥ 3 ischemic segments). Cox proportional hazards models were calculated to assess time to the primary end point of death or myocardial infarction.

RESULTS

At baseline, moderate to severe ischemia occurred in more than one-quarter of patients (n = 468), and the incidence was comparable in both treatment groups (P = .36). The primary end point, death or myocardial infarction, was similar in the OMT and PCI + OMT treatment groups for no to mild (18% and 19%, P = .92) and moderate to severe ischemia (19% and 22%, P = .53, interaction P value = .65). There was no gradient increase in events for the overall cohort with the extent of ischemia.

CONCLUSIONS

From the COURAGE trial post hoc substudy, the extent of site-defined ischemia did not predict adverse events and did not alter treatment effectiveness. Currently, evidence supports equipoise as to whether the extent and severity of ischemia impact on therapeutic effectiveness.

Safety profile of statins alone or combined with ezetimibe: a pooled analysis of 27 studies including over 22,000 patients treated for 6-24 weeks

Aims:  The aim of this analysis was to assess the overall safety and tolerability profiles of various statins + ezetimibe vs. statin monotherapy and to explore tolerability in sub-populations grouped by age, race, and sex. Methods:  Study-level data were combined from 27 double-blind, placebo-controlled or active-comparator trials that randomized adult hypercholesterolemic patients to statin or statin + ezetimibe for 6-24 weeks. In the full cohort, % patients with AEs within treatment groups (statin: N = 10,517; statin + ezetimibe: N = 11,714) was assessed by logistic regression with terms for first-/second-line therapy (first line = drug-naïve or rendered drug-naïve by washout at study entry; second line = ongoing statin at study entry or statin run-in), trial within first-/second-line therapy, and treatment. The same model was fitted for age (< 65, ≥ 65 years), sex, race (white, black, other) and first-/second-line subgroups with additional terms for subgroup and subgroup-by-treatment interaction. Results:  In the full cohort, the only significant difference between treatments was consecutive AST or ALT elevations ≥ 3 × upper limit of normal (ULN) (statin: 0.35%, statin + ezetimibe: 0.56%; p = 0.017). Significantly more subjects reported ≥ 1 AE; drug-related, hepatitis-related and gastrointestinal-related AEs; and CK elevations ≥ 10 × ULN (all p ≤ 0.008) in first-line vs. second-line therapy studies with both treatments. AEs were generally similar between treatments in subgroups, and similar rates of AEs were reported within age and race subgroups; however, women reported generally higher AE rates. Conclusions:  In conclusion, in second-line studies, ongoing statin treatment at study entry likely screened out participants for previous statin-related AEs and tolerability issues. These results describe the safety profiles of widely used lipid-lowering therapies and encourage their appropriate and judicious use in certain subpopulations.

Predictors of objectively measured medication nonadherence in adults with heart failure

BACKGROUND

Medication nonadherence rates are high. The factors predicting nonadherence in heart failure remain unclear.

METHODS AND RESULTS

A sample of 202 adults with heart failure was enrolled from the northeastern United States and followed for 6 months. Specific aims were to describe the types of objectively measured medication adherence (eg, taking, timing, dosing, drug holidays) and to identify contributors to nonadherence 6 months after enrollment. Latent growth mixture modeling was used to identify distinct trajectories of adherence. Indicators of the 5 World Health Organization dimensions of adherence (socioeconomic, condition, therapy, patient, and healthcare system) were tested to identify contributors to nonadherence. Two distinct trajectories were identified and labeled persistent adherence (77.8%) and steep decline (22.3%). Three contributors to the steep decline in adherence were identified. Participants with lapses in attention (adjusted OR, 2.65; P=0.023), those with excessive daytime sleepiness (OR, 2.51; P=0.037), and those with ≥2 medication dosings per day (OR, 2.59; P=0.016) were more likely to have a steep decline in adherence over time than to have persistent adherence.

CONCLUSIONS

Two distinct patterns of adherence were identified. Three potentially modifiable contributors to nonadherence have been identified.

ACCF/SCAI/STS/AATS/AHA/ASNC/HFSA/SCCT 2012 appropriate use criteria for coronary revascularization focused update: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, American Association for Thoracic Surgery, American Heart Association, American Society of Nuclear Cardiology, and the Society of Cardiovascular Computed Tomography

The American College of Cardiology Foundation (ACCF), Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, and the American Association for Thoracic Surgery, along with key specialty and subspecialty societies, conducted an update of the appropriate use criteria (AUC) for coronary revascularization frequently considered. In the initial document, 180 clinical scenarios were developed to mimic patient presentations encountered in everyday practice and included information on symptom status, extent of medical therapy, risk level as assessed by noninvasive testing, and coronary anatomy. This update provides a reassessment of clinical scenarios the writing group felt to be affected by significant changes in the medical literature or gaps from prior criteria. The methodology used in this update is similar to the initial document, and the definition of appropriateness was unchanged. The technical panel scored the clinical scenarios on a scale of 1 to 9. Scores of 7 to 9 indicate that revascularization is considered appropriate and likely to improve patients' health outcomes or survival. Scores of 1 to 3 indicate revascularization is considered inappropriate and unlikely to improve health outcomes or survival. Scores in the mid-range (4 to 6) indicate a clinical scenario for which the likelihood that coronary revascularization will improve health outcomes or survival is uncertain. In general, as seen with the prior AUC, the use of coronary revascularization for patients with acute coronary syndromes and combinations of significant symptoms and/or ischemia is appropriate. In contrast, revascularization of asymptomatic patients or patients with low-risk findings on noninvasive testing and minimal medical therapy are viewed less favorably. The technical panel felt that based on recent studies, coronary artery bypass grafting remains an appropriate method of revascularization for patients with high burden of coronary artery disease (CAD). Additionally, percutaneous coronary intervention may have a role in revascularization of patients with high burden of CAD. The primary objective of the appropriate use criteria is to improve physician decision making and patient education regarding expected benefits from revascularization and to guide future research.

Progression of atrial fibrillation in the REgistry on Cardiac rhythm disORDers assessing the control of Atrial Fibrillation cohort: clinical correlates and the effect of rhythm-control therapy

INTRODUCTION

Paroxysmal atrial fibrillation (AF) may progress to persistent AF. We studied the clinical correlates and the effect of rhythm-control strategy on AF progression.

METHODS

RecordAF was a worldwide prospective survey of AF management. Consecutive eligible patients with recent-onset AF were included and allocated to rate or rhythm control according to patient/physician choice. A total of 2,137 patients were followed up for 12 months. Atrial fibrillation progression was defined as a change from paroxysmal to persistent/permanent AF.

RESULTS

Progression of AF occurred in 318 patients (15%) after 1 year. Patients with AF progression were older; had a higher diastolic blood pressure; and more often had a history of coronary artery disease, stroke or transient ischemic attack, hypertension, or heart failure. Patients treated with rhythm control were less likely to show progression than those treated only with rate control (164/1542 [11%] vs 154/595 [26%], P < .001). Multivariable analysis showed that history of heart failure (odds ratio [OR] 2.2, 95% CI 1.7-2.9, P < .0001), history of hypertension (OR 1.5, 95% CI 1.1-2.0, P = .01), and rate control rather than rhythm control (OR 3.2, 95% CI 2.5-4.1, P < .0001) were independent predictors of AF progression. The propensity score-adjusted OR of AF progression in patients with rate rather than rhythm control was 3.3 (95% CI 2.4-4.6, P < .0001).

CONCLUSIONS

Although heart failure and hypertension are associated with AF progression, rhythm control is associated with lower risk of AF progression.

Comparative effectiveness of revascularization strategies

BACKGROUND

Questions persist concerning the comparative effectiveness of percutaneous coronary intervention (PCI) and coronary-artery bypass grafting (CABG). The American College of Cardiology Foundation (ACCF) and the Society of Thoracic Surgeons (STS) collaborated to compare the rates of long-term survival after PCI and CABG.

METHODS

We linked the ACCF National Cardiovascular Data Registry and the STS Adult Cardiac Surgery Database to claims data from the Centers for Medicare and Medicaid Services for the years 2004 through 2008. Outcomes were compared with the use of propensity scores and inverse-probability-weighting adjustment to reduce treatment-selection bias.

RESULTS

Among patients 65 years of age or older who had two-vessel or three-vessel coronary artery disease without acute myocardial infarction, 86,244 underwent CABG and 103,549 underwent PCI. The median follow-up period was 2.67 years. At 1 year, there was no significant difference in adjusted mortality between the groups (6.24% in the CABG group as compared with 6.55% in the PCI group; risk ratio, 0.95; 95% confidence interval [CI], 0.90 to 1.00). At 4 years, there was lower mortality with CABG than with PCI (16.4% vs. 20.8%; risk ratio, 0.79; 95% CI, 0.76 to 0.82). Similar results were noted in multiple subgroups and with the use of several different analytic methods. Residual confounding was assessed by means of a sensitivity analysis.

CONCLUSIONS

In this observational study, we found that, among older patients with multivessel coronary disease that did not require emergency treatment, there was a long-term survival advantage among patients who underwent CABG as compared with patients who underwent PCI. (Funded by the National Heart, Lung, and Blood Institute.).

Double jeopardy: the influence of excessive daytime sleepiness and impaired cognition on health-related quality of life in adults with heart failure

AIMS

To determine how excessive daytime sleepiness (EDS) and impaired cognition contribute to health-related quality of life (HRQL) in heart failure (HF).

METHODS AND RESULTS

Adults with chronic HF were enrolled into a prospective cohort study. Data were obtained from 280 subjects enrolled from three sites in the northeastern USA; 242 completed the 6-month study. At baseline, cohorts with and without EDS were identified using the Epworth Sleepiness Scale. Each EDS group was further subdivided into those with and without impaired cognition using a battery of five neuropsychological tests. Two disease-specific measures, the Kansas City Cardiomyopathy Questionnaire (KCCQ) and the Functional Outcomes of Sleep Questionnaire (FOSQ), were used to measure HRQL. General linear modelling of square-transformed variables was used to test the hypothesis that cohort membership was a significant predictor of HRQL. At 6 months the remaining sample was 62.5 [standard deviation (SD) 12] years old, mostly male (63%), white (65%), and functionally compromised [72% New York Heart Association (NYHA) class III/IV]. The cohort with both EDS and impaired cognition had the lowest KCCQ overall summary score (60.5 ± 22.5) compared with the cohort without EDS or impaired cognition (74.6 ± 17.4, P ≤ 0.001). A similar effect was seen on the FOSQ (16.0 ± 2.8 vs. 18.5 ± 2.2, P < 0.001).

CONCLUSION

Impaired cognition alone did not explain poor HRQL, but the addition of EDS poses a significant risk for poor HRQL. Interventions designed to influence EDS may improve HRQL in this population.

Abstract 49: The Effect of Gender, Obesity, and Chronic Kidney Disease on Cardiovascular Events

Background: Obesity and chronic kidney disease (CKD) are well known risk factors for cardiovascular (CV) events. Studies have shown that in patients with end-stage renal disease, the rate of CV events decreases as body mass index (BMI) increases. These studies, however, used only one measurement of BMI to predict CV events. The objective of this study was to assess whether rates of CV events changed according to variations in BMI and glomerular filtration rate (GFR) over time.

Methods: A retrospective cohort of patients followed in outpatient practices from 1995 to 2010 was evaluated. Adult patients with at least 2 records of serum creatinine were included. The practices’ electronic health records (EHRs) were linked to the hospital EHR to assess CV events. GFR (mL/min/1.73m 2 ) was calculated using the Modification of Diet in Renal Disease equation and stratified according to the Kidney Disease Outcomes Quality Initiative guidelines as Normal (≥ 60), CKD stage 3 (30-59) and stage 4-5 (< 30) at each patient’s encounter. Outcomes were identified using ICD9 codes for myocardial infarction, congestive heart failure, coronary heart disease, dysrhythmia, stroke and peripheral vascular disease. The data spanned up to 10 years from a patient’s index to last visit. CV events were modeled as a function of age, gender, race, BMI and CKD status by negative binomial regression for count data. The model included interactions of age, gender, race, BMI and CKD.

Results: Over the 10-year period, there were a total of 1,024,891 observations from 39,605 patients with 8,901 CV events. There was a significant age by gender by race by BMI interaction as well as a significant CKD main effect (p < 0.01). Increasing age, being male, black, overweight and having CKD, were associated with higher event rates. However, this association between BMI and event rates was not present for black females over 70, thus the 4-way sex by race by age by BMI interaction (Figure).

Conclusion: These results support the hypothesis that overweight / obesity is not protective of CV events in CKD patients.

Effectiveness of percutaneous coronary intervention in patients with silent myocardial ischemia (post hoc analysis of the COURAGE trial)

Previous studies have suggested that percutaneous coronary intervention (PCI) decreases long-term mortality in patients with silent myocardial ischemia (SMI), but whether PCI specifically decreases mortality when added to intensive medical therapy is unknown. We performed a post hoc analysis of clinical outcomes in patients in the COURAGE trial based on the presence or absence of anginal symptoms at baseline. Asymptomatic patients were classified as having SMI by electrocardiographic ischemia at rest or reversible stress perfusion imaging (exercise-induced or pharmacologic). Study end points included the composite primary end point (death or myocardial infarction [MI]); individual end points of death, MI, and hospitalization for acute coronary syndrome; and need for revascularization. Of 2,280 patients 12% (n = 283) had SMI and 88% were symptomatic (n = 1,997). There were no between-group differences in age, gender, cardiac risk factors, previous MI or revascularization, extent of angiographic disease, or ischemia by electrocardiogram or imaging. Compared to symptomatic patients, those with SMI had fewer subsequent revascularizations (16% vs 27%, p <0.001) regardless of treatment assignment and fewer hospitalizations for acute coronary syndrome (7% vs 12%, p <0.04). No significant differences in outcomes were observed between the 2 treatment groups, although there was a trend toward fewer deaths in the PCI group (n = 7, 5%) compared to the optimal medical therapy (OMT) group (n = 16, 11%, p = 0.12). In conclusion, addition of PCI to OMT did not decrease nonfatal cardiac events in patients with SMI but showed a trend toward fewer deaths. Although underpowered, given similar outcomes in other small studies, these findings suggest the need for an adequately powered trial of revascularization versus OMT in SMI patients.

Abstract 6: A Validated Contemporary Risk Model of Acute Kidney Injury in Patients Undergoing Percutaneous Coronary Interventions: Insights From the NCDR Cath-PCI Registry

Background: Acute Kidney Injury (AKI) is a serious complication of percutaneous coronary intervention (PCI) and is associated with adverse outcomes. Accurately estimating this risk may help clinicians better inform patients considering PCI of their potential risk of this complication.

Methods: Data were analyzed from 985,737 consecutive PCI patients performed at 1253 sites participating in the NCDR-Cath-PCI registry. AKI was defined as an absolute increase of ≥ 0.3 mg/dL or a relative increase of 50% in serum creatinine or a new requirement for dialysis following PCI (AKIN Stage 1 or greater). A parsimonious multivariable model in a 70% training cohort identified factors associated with AKI and assigned weighted integer scores. This score was validated in the remaining 30% of the population.

Results: Overall, 69,658 (7.1%) patients developed AKI with an associated in-hospital mortality of 9.7% versus 0.5% in those without AKI. The model identified 16 variables predictive of AKI (Figure 1). The parsimonious integer showed good discrimination in validation (c-statistic = 0.72). Patients with increasing risk score had increasing risk of predicted and observed rates of AKI across low, medium and high risk groups (Figure 2)

Conclusion: The NCDR AKI prediction model is a simple, contemporary and robust tool for predicting AKI in patients undergoing PCI. In certain clinical scenarios, the use of this tool may aid clinicians in counseling patient regarding the risk of PCI and identify patients for targeted interventions.

Abstract 220: Longer Door to Balloon Time: Effect of Chronic Kidney Disease on Each Step Leading to PCI

Purpose: Primary percutaneous coronary intervention (PCI) is a time-sensitive process. In high risk populations this time could be longer and affect the reperfusion results. The aim of this study was to examine the door-to-balloon time in patients with chronic kidney disease (CKD) and determine the influence of CKD at each step leading to PCI.

Methods: We conducted a retrospective study of patients admitted at an academic medical center for suspicion of acute coronary syndrome from 2004 to 2011. ICD9 codes were used to identify patients with myocardial infarction (MI) and comorbidities. CKD was defined using an estimated glomerular filtration rate (GFR) <60 mL/min/1.73 m 2 . ST segment elevation (STEMI) status was ascertained at hospital admission. In our hospital, date-times of each step (diagnostic ECG, alert for potential MI) are monitored. Non-parametric tests were used to compare time intervals according to GFR. Because the door-to-balloon time is right skewed, we log transformed time and modeled it as gamma distributed using a generalized estimating equation (GEE) to examine its association with CKD, after adjusting for age, gender, race, hypertension, congestive heart failure, and diabetes.

Results: Our study population included 712 patients with STEMI, of whom 138 (19.4%) had CKD (see table). Door-to-balloon time was longer in patients with GFR <30. Likewise diagnostic ECG-to-MI alert time was longer in patients with GFR <30 whereas MI alert-to-balloon time was not different between those with and without CKD. Results from the GEE showed that GFR<30 was an independent predictor of door-to-balloon time.

Conclusion: Patients with severe CKD have a longer door-to-balloon time than patients without CKD. This difference seems to be due to a longer time-interval between the time the diagnostic ECG is made and the time the MI alert is called. This delay in initiating PCI could be related to the misleading ECG (left ventricular hypertrophy, electrolyte and conduction abnormalities) frequently found in patients with CKD.

Abstract 260: Components of Change Processes of Quality of Life among Stable Coronary Patients with or without Percutaneous Coronary Intervention

Background: Percutaneous coronary intervention (PCI) plus intensive pharmacologic and lifestyle intervention (optimal medical therapy, OMT) to OMT alone was compared in reducing the risk of cardiovascular events in a total of 2,287 patients with stable coronary disease in the COURAGE trial, in which health related quality of life data were measured repeatedly over time for a median of 4.6 years. We examined components of changes in angina-related quality of life over time.

Methods: Angina-specific health status was assessed with the Seattle Angina Questionnaire (SAQ). Scores range from 0 to 100; higher scores indicate better health status. Linear piece-wise latent growth curve modeling was conducted to reveal the components of process and risk factors of SAQ score changes over time.

Results: For each domain the change process can be divided into two components: a process of improvement from baseline to 6 or 12 months during which the scores significantly increase with a steep upward trajectory till reaching the maximum score value; and followed by a process of stabilization during which the scores kept stable or in a downward slope until the end of the follow-up. Patients in both PCI and OMT alone groups experienced significant increase on SAQ scores over time in each domain. PCI had significant impact in the process of improvement: patients with PCI had about 0.603 (SE=0.193, p-value=0.002) and 0.442(SE=0.22, p-value =0.044) points increase per month in scores in the domains of physical limitation and angina frequency, respectively; the benefit of PCI decreased in the process of stabilization until it disappeared so that the scores in both groups were eventually similar (Table 1). The important risk factors of change in SAQ scores were the use of long-acting nitrates at randomization, the Charlson comorbidity index, and several additional factors that differed by domain.

Conclusions: Mechanism and processes of change in angina-related quality of life and health status were significantly related to the impact of adding PCI to OMT. Piece-wise growth curve modeling can be used to capture advantages of PCI over OMT and identify patient characteristics associated with subsequent measures of angina.

Prediction of long-term mortality after percutaneous coronary intervention in older adults: results from the National Cardiovascular Data Registry

BACKGROUND

The purpose of this study was to develop a long-term model to predict mortality after percutaneous coronary intervention in both patients with ST-segment elevation myocardial infarction and those with more stable coronary disease.

METHODS AND RESULTS

The American College of Cardiology Foundation CathPCI Registry data were linked to the Centers for Medicare and Medicaid Services 100% denominator file by probabilistic matching. Preprocedure demographic and clinical variables from the CathPCI Registry were used to predict the probability of death over 3 years as recorded in the Centers for Medicare and Medicaid Services database. Between 2004 and 2007, 343 466 patients (66%) of 518 195 patients aged ≥65 years undergoing first percutaneous coronary intervention in the CathPCI Registry were successfully linked to Centers for Medicare and Medicaid Services data. This study population was randomly divided into 60% derivation and 40% validation cohorts. Median follow-up was 15 months, with mortality of 3.0% at 30 days and 8.7%, 13.4%, and 18.7% at 1, 2, and 3 years, respectively. Twenty-four characteristics related to demographics, clinical comorbidity, prior history of disease, and indices of disease severity and acuity were identified as being associated with mortality. The C indices in the validation cohorts for patients with and without ST-segment elevation myocardial infarction were 0.79 and 0.78. The model calibrated well across a wide range of predicted probabilities.

CONCLUSIONS

On the basis of the large and nationally representative CathPCI Registry, we have developed a model that has excellent discrimination, calibration, and validation to predict survival up to 3 years after percutaneous coronary intervention.

Economic outcome of cardiac CT-based evaluation and standard of care for suspected acute coronary syndrome in the emergency department: a decision analytic model

RATIONALE AND OBJECTIVES

Cardiac computed tomography (CCT) in the emergency department may be cost saving for suspected acute coronary syndrome (ACS), but economic outcome data are limited. The objective of this study was to compare the cost of CCT-based evaluation versus standard of care (SOC) using the results of a clinical trial.

MATERIALS AND METHODS

We developed a decision analytic cost-minimization model to compare CCT-based and SOC evaluation costs to obtain a correct diagnosis. Model inputs, including Medicare-adjusted patient costs, were primarily obtained from a cohort study of 102 patients at low to intermediate risk for ACS who underwent an emergency department SOC clinical evaluation and a 64-channel CCT. SOC costs included stress testing in 77% of patients. Data from published literature completed the model inputs and expanded data ranges for sensitivity analyses.

RESULTS

Modeled mean patient costs for CCT-based evaluation were $750 (24%) lower than the SOC ($2384 and $3134, respectively). Sensitivity analyses indicated that CCT was less expensive over a wide range of estimates and was only more expensive with a CCT specificity below 67% or if more than 44% of very low risk patients had CCT. Probabilistic sensitivity analysis suggested that CCT-based evaluation had a 98.9% probability of being less expensive compared to SOC.

CONCLUSION

Using a decision analytic model, CCT-based evaluation resulted in overall lower cost than the SOC for possible ACS patients over a wide range of cost and outcome assumptions, including computed tomography-related complications and downstream costs.

Predictors of long-term survival after coronary artery bypass grafting surgery: results from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (the ASCERT study)

BACKGROUND

Most survival prediction models for coronary artery bypass grafting surgery are limited to in-hospital or 30-day end points. We estimate a long-term survival model using data from the Society of Thoracic Surgeons Adult Cardiac Surgery Database and Centers for Medicare and Medicaid Services.

METHODS AND RESULTS

The final study cohort included 348 341 isolated coronary artery bypass grafting patients aged ≥65 years, discharged between January 1, 2002, and December 31, 2007, from 917 Society of Thoracic Surgeons-participating hospitals, randomly divided into training (n=174 506) and validation (n=173 835) samples. Through linkage with Centers for Medicare and Medicaid Services claims data, we ascertained vital status from date of surgery through December 31, 2008 (1- to 6-year follow-up). Because the proportional hazards assumption was violated, we fit 4 Cox regression models conditional on being alive at the beginning of the following intervals: 0 to 30 days, 31 to 180 days, 181 days to 2 years, and >2 years. Kaplan-Meier-estimated mortality was 3.2% at 30 days, 6.4% at 180 days, 8.1% at 1 year, and 23.3% at 3 years of follow-up. Harrell's C statistic for predicting overall survival time was 0.732. Some risk factors (eg, emergency status, shock, reoperation) were strong predictors of short-term outcome but, for early survivors, became nonsignificant within 2 years. The adverse impact of some other risk factors (eg, dialysis-dependent renal failure, insulin-dependent diabetes mellitus) continued to increase.

CONCLUSIONS

Using clinical registry data and longitudinal claims data, we developed a long-term survival prediction model for isolated coronary artery bypass grafting. This provides valuable information for shared decision making, comparative effectiveness research, quality improvement, and provider profiling.

Linking the National Cardiovascular Data Registry CathPCI Registry With Medicare Claims Data

Background—

The National Cardiovascular Data Registry CathPCI Registry was recently linked with longitudinal Centers for Medicare & Medicaid (CMS) claims data. The degree to which this linked cohort is representative of the overall CathPCI Registry and CMS PCI populations is unknown.

Methods and Results—

CathPCI Registry records were linked to CMS inpatient claims using indirect identifiers. We examined the degree to which hospitals and patients in the linked cohort are representative of the elderly (≥65 years) CathPCI Registry and CMS populations. From 2004 to 2006, 1492 hospitals filed CMS PCI claims and 663 contributed CathPCI Registry data. Of these hospitals, 643 (97%) were linked across data sources. Compared with all CMS PCI hospitals, the linked data set contained fewer governmental, northeastern, southern, and low-volume (<200 beds) sites. Among CMS beneficiaries, 993 351 PCI procedures were performed, including 398 508 (40.1%) at centers in the linked database. Of these, 341 916 (86%) were linked to CathPCI Registry records. Linked and unlinked CMS patients had similar demographic and clinical features. In the CathPCI Registry database, 477 456 elderly patients underwent PCI, with 359 077 (75%) linked to CMS claims. Linked and unlinked National Cardiovascular Data Registry patients were similar, except for less commercial or health maintenance organization insurance in the linked cohort.

Conclusions—

By using deterministic matching strategies, a large and representative cohort with detailed clinical data from the CathPCI Registry and longitudinal follow-up from CMS claims has been created.