QRS duration, bundle-branch block morphology, and outcomes among older patients with heart failure receiving cardiac resynchronization therapy

IMPORTANCE

The benefits of cardiac resynchronization therapy (CRT) in clinical trials were greater among patients with left bundle-branch block (LBBB) or longer QRS duration.

OBJECTIVE

To measure associations between QRS duration and morphology and outcomes among patients receiving a CRT defibrillator (CRT-D) in clinical practice.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of Medicare beneficiaries in the National Cardiovascular Data Registry's ICD Registry between 2006 and 2009 who underwent CRT-D implantation. Patients were stratified according to whether they were admitted for CRT-D implantation or for another reason, then categorized as having either LBBB or no LBBB and QRS duration of either 150 ms or greater or 120 to 149 ms.

MAIN OUTCOMES AND MEASURES

All-cause mortality; all-cause, cardiovascular, and heart failure readmission; and complications. Patients underwent follow-up for up to 3 years, with follow-up through December 2011.

RESULTS

Among 24 169 patients admitted for CRT-D implantation, 1-year and 3-year mortality rates were 9.2% and 25.9%, respectively. All-cause readmission rates were 10.2% at 30 days and 43.3% at 1 year. Both the unadjusted rate and adjusted risk of 3-year mortality were lowest among patients with LBBB and QRS duration of 150 ms or greater (20.9%), compared with LBBB and QRS duration of 120 to 149 ms (26.5%; adjusted hazard ratio [HR], 1.30 [99% CI, 1.18-1.42]), no LBBB and QRS duration of 150 ms or greater (30.7%; HR, 1.34 [99% CI, 1.20-1.49]), and no LBBB and QRS duration of 120 to 149 ms (32.3%; HR, 1.52 [99% CI, 1.38-1.67]). The unadjusted rate and adjusted risk of 1-year all-cause readmission were also lowest among patients with LBBB and QRS duration of 150 ms or greater (38.6%), compared with LBBB and QRS duration of 120 to 149 ms (44.8%; adjusted HR, 1.18 [99% CI, 1.10-1.26]), no LBBB and QRS duration of 150 ms or greater (45.7%; HR, 1.16 [99% CI, 1.08-1.26]), and no LBBB and QRS duration of 120 to 149 ms (49.6%; HR, 1.31 [99% CI, 1.23-1.40]). There were no observed associations with complications.

CONCLUSIONS AND RELEVANCE

Among fee-for-service Medicare beneficiaries undergoing CRT-D implantation in clinical practice, LBBB and QRS duration of 150 ms or greater, compared with LBBB and QRS duration less than 150 ms or no LBBB regardless of QRS duration, was associated with lower risk of all-cause mortality and of all-cause, cardiovascular, and heart failure readmissions.

Association of single- vs dual-chamber ICDs with mortality, readmissions, and complications among patients receiving an ICD for primary prevention

IMPORTANCE

Randomized trials of implantable cardioverter-defibrillators (ICDs) for primary prevention predominantly used single-chamber devices. In clinical practice, patients often receive dual-chamber ICDs, even without clear indications for pacing. The outcomes of dual- vs single-chamber devices are uncertain.

OBJECTIVE

To compare outcomes of single- and dual-chamber ICDs for primary prevention of sudden cardiac death.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of admissions in the National Cardiovascular Data Registry's (NCDR) ICD registry from 2006-2009 that could be linked to Centers for Medicare & Medicaid Services fee-for-service Medicare claims data. Patients were included if they received an ICD for primary prevention and did not have a documented indication for pacing.

MAIN OUTCOMES AND MEASURES

Adjusted risks of 1-year mortality, all-cause readmission, heart failure readmission, and device-related complications within 90 days were estimated with propensity-score matching based on patient, clinician, and hospital factors.

RESULTS

Among 32,034 patients, 12,246 (38%) received a single-chamber device and 19,788 (62%) received a dual-chamber device. In a propensity-matched cohort, rates of complications were lower for single-chamber devices (3.51% vs 4.72%; P < .001; risk difference, -1.20 [95% CI, -1.72 to -0.69]), but device type was not significantly associated with 1-year mortality (unadjusted rate, 9.85% vs 9.77%; hazard ratio [HR], 0.99 [95% CI, 0.91 to 1.07]; P = .79), 1-year all-cause hospitalization (unadjusted rate, 43.86% vs 44.83%; HR, 1.00 [95% CI, 0.97-1.04]; P = .82), or hospitalization for heart failure (unadjusted rate, 14.73% vs 15.38%; HR, 1.05 [95% CI, 0.99-1.12]; P = .19).

CONCLUSIONS AND RELEVANCE

Among patients receiving an ICD for primary prevention without indications for pacing, the use of a dual-chamber device compared with a single-chamber device was associated with a higher risk of device-related complications and similar 1-year mortality and hospitalization outcomes. Reasons for preferentially using dual-chamber ICDs in this setting remains unclear.

Abstract 91: Temporal Trends in Patient Characteristics and Outcomes Among Medicare Beneficiaries Undergoing Primary Prevention Implantable Cardioverter-Defibrillator Placement in the United States: 2006-2010 Results from the NCDR ®

Background: Trends in the use and outcomes of ICDs in community practice settings are not well characterized. Our objective was to determine the temporal trends in characteristics and outcomes among patients undergoing primary prevention ICD therapy.

Methods: We identified Medicare beneficiaries aged 65 years and older with an ejection fraction <35% undergoing ICD implantation for primary prevention between 2006 and 2010 in the NCDR ICD Registry™. Using a probabilistic method, eligible subjects were matched to Medicare claims data to capture outcomes using age, gender, admission date or procedure date, and hospital Medicare provider number. We tested the significance of trends in characteristics over time with χ2 tests for categorical variables and ANOVA for continuous variables. Standardized outcome rates were calculated adjusting for demographics and characteristics.

Results: A total of 117,100 patients were included in the analysis. Between 2006 and 2010, small but significant increases were observed in the prevalence of hypertension, diabetes, and NYHA Class III symptoms, and decreases in the prevalence of ischemic heart disease and NYHA Class IV symptoms (Table 1). There was minimal change in age, gender, and race of patients receiving ICDs over the study period; fewer single lead and more biventricular devices were used over time. Risk-standardized six-month re-hospitalization and complication rates decreased and risk-standardized six-month all-cause mortality was stable over the study period (Table 1).

Conclusions: Modest changes in patient characteristics undergoing primary prevention ICD implantation were observed between 2006 and 2010. There have simultaneously been significant improvements in outcomes after accounting for these patient trends, suggesting the possibility that there have been improvements in care of this patient population.

Abstract 327: Gender Differences In The Association Between Hemoglobin Change After Acute Myocardial Infarction And Outcomes

Background: Hemoglobin decline following acute myocardial infarction (AMI) is associated with long-term morbidity. Since women have lower baseline hemoglobin levels than men, whether the same absolute change in hemoglobin after AMI similarly affects outcomes in women and men is unknown.

Methods: We examined patients discharged after AMI in the TRIUMPH registry between 2005 and 2008 who had admission and discharge hemoglobin levels. We compared the relationship between absolute change in hemoglobin during hospitalization with 6- and 12-month mortality and re-hospitalization by gender after adjusting for clinical variables including admission hemoglobin.

Results: Of the 4,243 patients with AMI, 33% (1,400 of 4,243) were women. Women were older, had more co-morbidities, and were less likely to present with STEMI, or receive catheterization. Women had lower admission hemoglobin (12.9 g/dL ± 1.9 vs 14.5 ± 2.0, p= <0.01) and a smaller mean absolute change in hemoglobin during hospitalization (-1.5 g/dL ± 1.8 vs -1.6 ±1.8, p = 0.01) compared to men. The association between hemoglobin declines during hospitalization and mortality and re-hospitalization rates at 6 and 12-months were of a similar magnitude between men and women (all interaction p > 0.05). (Figure 1)

Conclusion: Although women with AMI had lower admission hemoglobin values, similar declines in hemoglobin during hospitalization were associated with increases in mortality and re-hospitalization in women and men. These findings suggest that absolute change in hemoglobin is equally important at predicting outcomes in women and men, regardless of admission hemoglobin levels.

Abstract 141: Incremental Prognostic Value Of Serial Health Status Measures For Ambulatory Patients With Heart Failure

Background: Existing heart failure (HF) risk models have only moderate performance for adverse outcomes. Whether serial health status measurements can improve risk stratification is unknown.

Methods: In 2007 and again in 2008, we administered Kansas City Cardiomyopathy Questionnaires (KCCQ) to ambulatory Kaiser Permanente Colorado enrollees with a history of HF hospitalization between 2001 and 2007 who survived through 2008. The primary endpoint was hospitalization or death in the 6 months following the 2008 KCCQ administration. C-statistics, integrated discrimination indices (IDI), and net reclassification indices (NRI) were calculated; event rate thresholds for NRI were low (30%).

Results: Survey response rates were 71% in 2007 and 69% in 2008, resulting in a cohort of 629 patients who completed both questionnaires, of which 153 experienced the endpoint. Mean age was 75 years, 51% were women, mean LVEF was 49%, and mean KCCQ score was 69. Compared with a base model using well accepted demographic and clinical covariates (Model 3, Table), the 2008 KCCQ score appropriately reclassified a large percentage of patients (NRI 13.0%). Adding the change in KCCQ did not further improve reclassification (NRI -3.0%).

Conclusions: A recent measure of health status, added to traditional prognostic markers, significantly improved risk stratification among a broad ambulatory HF population. Although important patient-centered outcomes in their own right, temporal trends in health status did not further improve prognostication, as compared with the most recent health status assessment. Thus serial health status assessments provide an ‘up-to-date’ assessment of a patient’s prognoses by focusing on the latest values, rather than previous ones.

Longitudinal study of implantable cardioverter-defibrillators: methods and clinical characteristics of patients receiving implantable cardioverter-defibrillators for primary prevention in contemporary practice

BACKGROUND

Implantable cardioverter-defibrillators (ICDs) are increasingly used for primary prevention after randomized, controlled trials demonstrating that they reduce the risk of death in patients with left ventricular systolic dysfunction. The extent to which the clinical characteristics and long-term outcomes of unselected, community-based patients with left ventricular systolic dysfunction undergoing primary prevention ICD implantation in a real-world setting compare with those enrolled in the randomized, controlled trials is not well characterized. This study is being conducted to address these questions.

METHODS AND RESULTS

The study cohort includes consecutive patients undergoing primary prevention ICD placement between January 1, 2006 and December 31, 2009 in 7 health plans. Baseline clinical characteristics were acquired from the National Cardiovascular Data Registry ICD Registry. Longitudinal data collection is underway, and will include hospitalization, mortality, and resource use from standardized health plan data archives. Data regarding ICD therapies will be obtained through chart abstraction and adjudicated by a panel of experts in device therapy. Compared with the populations of primary prevention ICD therapy randomized, controlled trials, the cohort (n=2621) is on average significantly older (by 2.5-6.5 years), more often female, more often from racial and ethnic minority groups, and has a higher burden of coexisting conditions. The cohort is similar, however, to a national population undergoing primary prevention ICD placement.

CONCLUSIONS

Patients undergoing primary prevention ICD implantation in this study differ from those enrolled in the randomized, controlled trials that established the efficacy of ICDs. Understanding a broad range of health outcomes, including ICD therapies, will provide patients, clinicians, and policy makers with contemporary data to inform decision-making.

Effects of mineralocorticoid receptor antagonists on the risk of sudden cardiac death in patients with left ventricular systolic dysfunction: a meta-analysis of randomized controlled trials

BACKGROUND

Sudden cardiac death (SCD) is an important cause of death in patients with left ventricular systolic dysfunction. Mineralocorticoid receptor antagonists (MRAs) may attenuate this risk. The objective of this meta-analysis was to assess the impact of MRAs on SCD in patients with left ventricular systolic dysfunction.

METHODS AND RESULTS

We systematically searched PubMed, EMBASE, Cochrane, and other databases through March 30, 2012, without language restrictions. We included trials that enrolled patients with left ventricular ejection fraction of ≤45%, randomized subjects to MRAs versus control and reported outcomes on SCD, total and cardiovascular mortality. Eight published trials that enrolled 11 875 patients met inclusion criteria. Of these, 6 reported data on SCD and cardiovascular mortality, and 7 reported data on total mortality. No heterogeneity was observed among the trials. Patients treated with MRAs had 23% lower odds of experiencing SCD compared with controls (odds ratio, 0.77; 95% confidence interval, 0.66-0.89; P=0.001). Similar reductions were observed in cardiovascular (0.75; 95% confidence interval, 0.68-0.84; P<0.001) and total mortality (odds ratio, 0.74; 95% confidence interval, 0.63-0.86; P<0.001). Although publication bias was observed, the results did not change after a trim and fill test, suggesting that the impact of this bias was likely insignificant.

CONCLUSIONS

MRAs reduce the risk of SCD in patients with left ventricular systolic dysfunction. Comparative effectiveness studies of MRAs on SCD in usual care as well as studies evaluating the efficacy of other therapies to prevent SCD in patients receiving optimal MRA therapy are needed to guide clinical decision-making.

Patterns of beta-blocker intensification in ambulatory heart failure patients and short-term association with hospitalization

Background

In response to the short-term negative inotropic and chronotropic effects of β-blockers, heart failure (HF) guidelines recommend initiating β-blockers at low dose with gradual uptitration as tolerated to doses used in clinical trials. However, patterns and safety of β-blocker intensification in routine practice are poorly described.

Methods

We described β-blocker intensification among Kaiser Colorado enrollees with a primary discharge diagnosis of HF between 2001–2009. We then assessed β-blocker intensification in the 30 days prior to first hospital readmission for cases compared to the same time period following index hospitalization for non-rehospitalized matched controls. In separate analysis of the subgroup initiated on β-blocker after index hospital discharge, we compared adjusted rates of 30-day hospitalization following initiation of high versus low dose β-blocker.

Results

Among 3,227 patients, median age was 76 years and 37% had ejection fraction ≤40% (LVSD). During a median follow up of 669 days, 14% were never on β-blocker, 21% were initiated on β-blocker, 43% were discharged on β-blocker but never uptitrated, and 22% had discharge β-blocker uptitrated; 63% were readmitted and 49% died. β-blocker intensification occurred in the 30 days preceding readmission for 39 of 1,674 (2.3%) readmitted cases compared to 27 (1.6%) of matched controls (adjusted OR 1.36, 95% CI 0.81-2.27). Among patients initiated on therapy, readmission over the subsequent 30 days occurred in 6 of 155 (3.9%) prescribed high dose and 9 of 513 (1.8%) prescribed low dose β-blocker (adjusted OR 3.10, 95% CI 1.02-9.40). For the subgroup with LVSD, findings were not significantly different.

Conclusion

While β-blockers were intensified in nearly half of patients following hospital discharge and high starting dose was associated with increased readmission risk, the prevailing finding was that readmission events were rarely preceded by β-blocker intensification. These data suggest that β-blocker intensification is not a major precipitant of hospitalization, provided recommended dosing is followed.

Variation in use of dual-chamber implantable cardioverter-defibrillators: results from the national cardiovascular data registry

BACKGROUND

Among patients without an indication for a pacemaker, current evidence is inconclusive whether a dual-chamber implantable cardioverter-defibrillator (ICD) is superior to a single-chamber ICD. The current use of dual-chamber ICDs is not well characterized.

METHODS

We conducted a cross-sectional study exploring hospital-level variation in the use of dual-chamber ICDs across the United States. Patients receiving a primary prevention ICD from 2006 through 2009 without a documented indication for a pacemaker were included. Multivariate hierarchical logistic regression was used to explore patient, health care provider, and physician factors related to the use of a dual-chamber device.

RESULTS

Dual-chamber devices were implanted in 58% of the 87,115 patients without a pacing indication among 1293 hospitals, with hospital rates ranging from 0% in 33 centers to 100% in 109 centers. In multivariate analysis, geographic region was a strong independent predictor of dual-chamber device use, ranging from 36.4% in New England (reference region) to 66.4% in the Pacific region (odds ratio [OR], 5.25; 95% CI, 3.35-8.21). Hospital clustering was assessed using a median OR which was 3.96, meaning that 2 identical patients at different hospitals would have nearly a 4-fold difference in their chance of receiving a dual-chamber ICD.

CONCLUSIONS

Use of dual-chamber ICDs for the primary prevention of sudden cardiac death among patients without an indication for permanent pacing varies markedly at the hospital level in the United States. This is a clear example of how practice can vary independent of patient factors.

Abstract 75: Practice-level Variation in use of Recommended Medications among Outpatients with Heart Failure: Insights from the NCDR PINNACLE Program

Background: Beta-blockers (BB) and angiotensin converting enzyme inhibitors (ACE)/angiotensin receptor blockers (ARB) are guideline recommended therapies for ambulatory heart failure patients with reduced left ventricular ejection fraction (HFREF). Real-world use of these therapies is suboptimal. Whether variations in treatment are dominated by practice-level or patient-level factors is unknown.

Methods: Practices participating in the NCDR PINNACLE program, a national office-based cardiac quality improvement registry, between July 2008 and December 2010 were evaluated. Rates of treatment with BB and ACE/ARB were evaluated in patients with HFREF (EF ≤40%) and no documented contraindication. Multivariable hierarchical relative risk regression models, including demographics, insurance status, comorbidities and a random effect for practice were used to determine 1) patient-level and 2) practice-level variation in treatment rates. To quantify practice-level variation, the median rate ratio (MRR) was calculated, which estimates the typical rate ratio between two randomly selected practices for patients with identical covariates. In general, MRRs ≥ 1.2 indicate significant variation by practice. The MRR is always >1.0 but can be compared in magnitude to patient-level risks.

Results: We studied 12384 patients in 45 practices. The mean practice rate for BB treatment was 87% (IQR 83%-95%; range: 43%-100%), and the mean practice rate of ACE/ARB treatment was 90% (IQR 75%-88%; range: 18%-100%). The MRR was 1.09 for BB and 1.16 for ACE/ARB therapy. For both BB and ACE/ARB, the adjusted MRR for site level variation was larger than the rate ratio for other patient factors. (Table)

Conclusions: Although rates of BB and ACE/ARB treatment among outpatients with HFREF are high, clinically meaningful variation by practice is present and explains a larger amount of the observed variance than any patient characteristic. This suggests that addressing practice-level factors represents an important opportunity to improve the use of evidence-based HF therapy.

Abstract 18: Aldosterone Antagonists Prevent Sudden Cardiac Death in patients with Left Ventricular Systolic Dysfunction: a Meta-Analysis of Randomized Controlled Trials

Background: Sudden Cardiac Death (SCD) is a leading cause of mortality in patients with left ventricular systolic dysfunction (LVSD). The renin-angiotensin-aldosterone pathway has been implicated in the pathogenesis of SCD. A meta-analysis of randomized controlled trials (RCTs) to assess the impact of aldosterone antagonists (AA) on SCD in patients with LVSD has been lacking.

Methods: We systematically searched PubMed, EMBASE, Cochrane, US Food and Drug Administration and Clinical Trials databases through March 31, 2011 without language restrictions. We included trials that enrolled patients with LVSD (LV ejection fraction ≤ 45%), randomized subjects to an AA vs. placebo, and reported outcomes of SCD. Pooled odds ratios were calculated using DerSimonian and Laird random effects model. Heterogeneity was measured by Cochran’s Q test and I 2 statistic. Sensitivity analysis was performed to evaluate the strength of our model. Publication bias was explored with a funnel plot and Eggers test. A two sided p-value of < 0.05 was considered statistically significant.

Results: We identified six published trials, which enrolled 11,654 patients, and met inclusion criteria (Table 1). No significant heterogeneity was observed among the trials. Patients with LVSD treated with AA had 23% lower odds of experiencing SCD compared with controls. Similar results were observed with secondary outcomes of total and cardiovascular mortality. Sensitivity analysis did not significantly change the odds ratio. Significant publication bias was observed (asymmetrical funnel plot and Eggers test p = 0.01) due to the inclusion of small trials with less precision and large trials with high effect size in the final synthesis. We found a trivial shift in the effect size from 0.770 to 0.776 after a trim and fill test to account for hypothetically missed studies suggesting that the impact of the publication bias on these findings is probably insignificant.

Conclusions: AA reduce the risk of SCD in patients with LVSD. Comparative effectiveness studies of AA on SCD in the usual care setting as well as other SCD-prevention strategies in the setting of AA use are needed.

Abstract 24: Outcomes of Single and Dual Chamber ICDs for Primary Prevention of Sudden Cardiac Death

Background: Randomized trials demonstrating the efficacy of implantable cardioverter defibrillator (ICD) therapy for primary prevention of sudden cardiac death in patients with systolic heart failure (HF) predominantly used single chamber devices. However, in clinical practice, patients often receive dual chamber ICDs even in the absence of indications for pacing. The long-term safety of dual chamber devices relative to single chamber devices is uncertain.

Methods: We identified all Medicare patients in the National Cardiovascular Data Registry's (NCDR®) ICD Registry™ from 2006-2009 who received an ICD for primary prevention that could be matched to CMS claims data. Patients were excluded if they had an EF >35%, received a bi-ventricular device or had a documented indication for pacing. Adjusted risks of complications, mortality, all cause readmission and HF readmission were estimated with propensity-score matching based on demographic, clinical and diagnostic information.

Results: Among 32,034 eligible patients, 38% (n=12,246) received single chamber device and 62% (n=19,788) received a dual chamber device. Unadjusted rates of complications and 6-month all-cause readmission were lower among patients who received a single chamber device (3.5% vs. 4.8%; p <0.001, and 31.7% vs. 33.2%; p=0.004). According to analysis of matched pairs (12,133 single and 12,133 dual), rates of complications were lower among patients who received a single chamber device (3.5% vs.4.6%; p<0.001), but rates of all other outcomes did not differ significantly between the two groups. (Table)

Conclusions: Dual chamber ICDs are associated with higher rates of complications. No significant differences between single and dual chamber ICDs were observed for death, all-cause readmission or HF readmission. Future studies should evaluate the potential benefit of dual chamber devices in reducing inappropriate shocks. In Medicare patients undergoing primary prevention ICD placement without clear indications for pacing, the decision to implant a dual chamber device should be considered carefully given the higher risk of complications with this strategy.

Adherence to risk factor management instructions after acute myocardial infarction: the role of emotional support and depressive symptoms

BACKGROUND

Emotional support and depression may influence adherence to risk factor management instructions after acute myocardial infarction (AMI), but their role requires further investigation.

PURPOSE

To examine the longitudinal association between perceived emotional support and risk factor management adherence and assess depressive symptoms as a moderator of this association.

METHODS

Among 2,202 AMI patients, we assessed adherence to risk factor management instructions over the first recovery year. Modified Poisson mixed-effects regression evaluated associations, with adjustment for demographic and clinical factors.

RESULTS

Patients with low baseline support had greater risk of poor adherence over the first year than patients with high baseline support (relative risk [RR] = 1.20, 95% confidence interval [CI] = 1.02-1.43). In stratified analyses, low support remained a significant predictor of poor adherence for non-depressed (RR = 1.41, 95% CI = 1.23-1.61) but not depressed (RR = 1.01, 95% CI = 0.78-1.30) patients (p for interaction < 0.001).

CONCLUSIONS

Low emotional support is associated with poor risk factor management adherence after AMI. This relationship is moderated by depression, with a significant relationship observed only among non-depressed patients.

Abstract 257: Practice Variation is a Significant Contributor to Secondary Prevention Medication Use: Insights from the NCDR PINNACLE Program

Background: Secondary prevention medications for eligible CAD patients include antiplatelets, lipid lowering agents, beta-blockers (BB) and angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). However, use of these therapies is variable. The contribution of practice-level factors to variation in medication use is unknown. In addition, the contribution of practice-level factors relative to patient factors is also unknown.

Methods: We evaluated CAD patients in cardiology practices participating in the NCDR PINNACLE program, a national office-based cardiac quality improvement registry, between July 2008 and December 2010. Patients eligible for treatment were grouped by Class I indications for therapy: antiplatelets and lipid lowering agents in all, BBs in post-MI patients, and ACEIs/ARBs in those with diabetes or with reduced left ventricular ejection fraction (≤40%). Mean practice rates of therapy use were calculated. Next, hierarchical regression models assessed the effect of practice on therapy use, adjusted for patient factors, using the median rate ratio (MRR). The MRR compares the likelihood of treatment for identical patients from two randomly selected practices. In general, MRRs ≥ 1.2 indicate significant variation by practice. Finally, the magnitude of contribution of patient factors, expressed in ORs, to variation in therapy use was assessed.

Results: Our cohort consisted of 277,526 patients in 62 practices. The mean practice rate was 80.8% for antiplatelets (range 41.2–100%), 79.5% for lipid lowering agents (range 33.9–100%), 77.6% for BBs (range 35.2–100%), and 73.8% for ACEI/ARBs (range 39.1–100%). Adjusted MRR between practices was 1.19 for antiplatelets, 1.19 for lipid lowering agents, 1.20 for BBs, and 1.19 for ACEIs/ARBs. Almost all patient-level factors were smaller in magnitude than the MRR for practice-level variation (see Table).

Conclusions: Among practices participating in the PINNACLE program, significant variation in guideline recommended treatments among CAD outpatients exists. Practice setting, independent of patient factors, was associated with variation in treatment and was similar in magnitude to most patient factors. Our findings suggest that practice setting is an important contributor to variability in secondary prevention medication use. Accordingly, to improve the use of evidence-based CAD therapies, quality improvement efforts targeting practice-level factors should be evaluated.

Acculturation and outcomes among patients with heart failure

BACKGROUND

Acculturation to US society among minority patients may-beyond race and ethnicity alone-influence health outcomes beyond race and ethnicity alone. In particular, those who are foreign-born and who do not speak English as their primary language may have greater challenges interacting with the health care system and thus be at greater risk for adverse outcomes.

METHODS AND RESULTS

We studied patients hospitalized with a principal discharge diagnosis of heart failure between January 2000 and December 2007 in an integrated delivery system that cares for minority patients. Individuals were defined as having low acculturation if their primary language was not English and their country of birth was outside of the United States. Multivariable logistic regression and Cox proportional hazards regression were used to determine the independent risk of 30-day rehospitalization and 1-year mortality, respectively. Candidate adjustment variables included demographics (age, sex, race/ethnicity), coexisting illnesses, laboratory values, left ventricular systolic function, and characteristics of the index admission. Of 1268 patients, 30% (n=379) were black, 39% (n=498) were Hispanic, and 27% (n=348) were white. Eighteen percent (n=228) had low acculturation. After adjustment, low acculturation was associated with a higher risk of readmission at 30 days (odds ratio, 1.70; 95% confidence interval, 1.07-2.68) but not 1-year all-cause mortality (hazard ratio, 0.69; 95% confidence interval, 0.42-1.14).

CONCLUSIONS

Patients with heart failure who are foreign-born and do not speak English as their primary language have a greater risk of rehospitalization, independent of clinical factors and race/ethnicity. Future studies should evaluate whether culturally concordant interventions focusing on such patients may improve outcomes for this patient population.

Abstract P206: Changes in Social Support Within the Early Recovery Period and Outcomes After Acute Myocardial Infarction

Background: Baseline social support is associated with outcomes after AMI. However, little is known about changes in social support during the early AMI recovery period and whether changes influence outcomes over the first year.

Methods: Using data from 1951 AMI patients enrolled in the 19-center PREMIER study, we longitudinally examined whether changes in social support between baseline (index hospitalization) and 1 month post-AMI were associated with health status and depressive symptom outcomes. Using 5 items from the ENRICHD Social Support Inventory, we categorized patients into low (score <=18) and high (score >18) support and examined changes between these categories during the first month of recovery. Health status and depressive symptoms were assessed at baseline, 6, and 12 months using the Seattle Angina Questionnaire (SAQ), Short Form-12 (SF-12), and the Patient Health Questionnaire-9 (PHQ-9). Associations were evaluated using hierarchical repeated-measures regression, adjusting for site, baseline health status, depressive symptoms, and other sociodemographic and clinical factors.

Results: During the first month of recovery, 5.6% of patients had persistently low support, 6.4% had worsened support, 8.1% had improved support, and 80.0% had persistently high support. In risk-adjusted analyses, patients with persistently low or worsened support (versus those with persistently high support) had greater risk of angina, worse SAQ quality of life (QOL), worse SF-12 mental component summary (MCS), and more PHQ-9 depressive symptoms ( table ). Patients with improved support had outcomes consistent with those of patients with persistently high support ( table ). Similarly, patients with worsened support had outcomes comparable to patients with persistently low support (p>0.50 for all comparisons).

Conclusion: Changes in social support within the early recovery period are not uncommon and are important for predicting patient-centered outcomes.

Outcome Social Support Status at 1 Month Persistently Low Worsened Improved Persistently High SAQ Angina * 1.39 (1.09, 1.78) 1.46 (1.08, 1.97) 1.13 (0.89, 1.43) reference SAQ QoL † -7.63 (-10.96, -4.30) -7.44 (-10.54, -4.34) -0.85 (-3.49, 1.80) reference SF-12 PCS † -0.14 (-2.20, 1.91) -0.20 (-2.14, 1.73) -0.44 (-2.07, 1.18) reference SF-12 MCS † -5.63 (-7.33, -3.92) -4.82 (-6.42, -3.22) -1.54 (-2.88, -0.20) reference PHQ-9 † 2.29 (1.51, 3.06) 1.94 (1.22, 2.66) 0.81 (0.19, 1.43) reference *

Abstract P73: Social Support and Adherence to Cardiac Risk Factor Management Instructions during the First Year after Acute Myocardial Infarction

Background: Adherence to risk factor management (RFM) instructions after AMI can promote recovery. The prognostic importance of social support for adherence is not well understood. We examined the relationship between baseline social support and post-AMI RFM adherence, and tested whether depression moderates this association.

Methods: Using data from 2202 AMI patients enrolled in the 19-site PREMIER study, we longitudinally examined whether low baseline social support (index hospitalization; score <=18 on 5 items from ENRICHD Social Support Inventory) is associated with poor adherence to 13 RFM instructions (medication adherence, warfarin use, follow-up plan/appointments, whom to call, cholesterol monitoring and therapy, diabetes management, weight monitoring and loss, smoking cessation, diet, exercise, cardiac rehabilitation) within the first year of recovery. Patients were asked at 1, 6, and 12 months if they received any of the RFM instructions since their last interview. Poor adherence was defined a priori as adhering “very carefully” to less than 50% of the patient-appropriate instructions. Hierarchical repeated-measures Poisson regression evaluated the association between support and adherence, with adjustment for site, sociodemographics, clinical history and presentation, hospital and outpatient care, and depression. Whether depression (PHQ-9 score >=10) modified the association was evaluated by stratifying the risk-adjusted model by depression status and including a support*depression interaction term.

Results: Patients with low social support had greater unadjusted risk of poor adherence than patients with high social support (RR 1.46, 95% CI 1.27-1.67). This association did not vary with time and remained significant after full risk adjustment (RR 1.24, 95% CI 1.05-1.47). In depression-stratified analyses, the risk-adjusted association of low support with poor adherence was significant among nondepressed (RR 1.44, 95% CI 1.26-1.66) but not depressed (RR 1.03, 95% CI 0.79-1.33) patients (p<0.001 for support*depression interaction).

Conclusion: Good social support may improve adherence among nondepressed AMI patients, but more research is needed to understand the role of social support among depressed patients.