Imaging modality for left ventricular ejection fraction estimation and effect of implantable cardioverter-defibrillator on mortality in patients with heart failure.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) improve outcomes in patients with heart failure (HF) with left ventricular ejection fraction (LVEF) ≤35%. Less is known about whether outcomes varied between the 2 noninvasive imaging modalities used to estimate LVEF-2-dimensional echocardiography (2DE) and multigated acquisition radionuclide ventriculography (MUGA)-which use different principles (geometric vs count-based, respectively). OBJECTIVE: The purpose of this study was to examine whether the effect of ICD on mortality in patients with HF and LVEF ≤35% varied on the basis of LVEF measured by 2DE or MUGA. METHODS: Of the 2521 patients with HF with LVEF ≤35% in the Sudden Cardiac Death in Heart Failure Trial, 1676 (66%) were randomized to either placebo or ICD, of whom 1386 (83%) had LVEF measured by 2DE (n = 971) or MUGA (n = 415). Hazard ratios (HRs) and 97.5% confidence intervals (CIs) for mortality associated with ICD were estimated overall, checking for interaction, and within the 2 imaging subgroups. RESULTS: Of the 1386 patients in the present analysis, all-cause mortality occurred in 23.1% (160 of 692) and 29.7% (206 of 694) of patients randomized to ICD or placebo, respectively (HR 0.77; 97.5% CI 0.61-0.97), which is consistent with that in 1676 patients in the original report. HRs (97.5% CIs) for all-cause mortality in the 2DE and MUGA subgroups were 0.79 (0.60-1.04) and 0.72 (0.46-1.11), respectively (P = .693 for interaction). Similar associations were observed for cardiac and arrhythmic mortalities. CONCLUSION: We found no evidence that in patients with HF and LVEF ≤35%, the effect of ICD on mortality varied by the noninvasive imaging method used to measure LVEF.

Hydroxychloroquine and Risk of Long QT Syndrome in Rheumatoid Arthritis: A Veterans Cohort Study With Nineteen-Year Follow-up.

OBJECTIVE: Recent evidence suggests that hydroxychloroquine use is not associated with higher 1-year risk of long QT syndrome (LQTS) in patients with rheumatoid arthritis (RA). Less is known about its long-term risk, the examination of which was the objective of this study. METHODS: We conducted a propensity score-matched active-comparator safety study of hydroxychloroquine in 8,852 veterans (mean age 64 ± 12 years, 14% women, 28% Black) with newly diagnosed RA. A total of 4,426 patients started on hydroxychloroquine and 4,426 started on another nonbiologic disease-modifying antirheumatic drug (DMARD) and were balanced on 87 baseline characteristics. The primary outcome was LQTS during 19-year follow-up through December 31, 2019. RESULTS: Incident LQTS occurred in 4 (0.09%) and 5 (0.11%) patients in the hydroxychloroquine and other DMARD groups, respectively, during the first 2 years. Respective 5-year incidences were 17 (0.38%) and 6 (0.14%), representing 11 additional LQTS events in the hydroxychloroquine group (number needed to harm 403; [95% confidence interval (95% CI)], 217-1,740) and a 181% greater relative risk (95% CI 11%-613%; P = 0.030). Although overall 10-year risk remained significant (hazard ratio 2.17; 95% CI 1.13-4.18), only 5 extra LQTS occurred in hydroxychloroquine group over the next 5 years (years 6-10) and 1 over the next 9 years (years 11-19). There was no association with arrhythmia-related hospitalization or all-cause mortality. CONCLUSIONS: Hydroxychloroquine use had no association with LQTS during the first 2 years after initiation of therapy. There was a higher risk thereafter that became significant after 5 years of therapy. However, the 5-year absolute risk was very low, and the absolute risk difference was even lower. Both risks attenuated during longer follow-up. These findings provide evidence for long-term safety of hydroxychloroquine in patients with RA.

Cardiovascular Safety of Hydroxychloroquine in US Veterans With Rheumatoid Arthritis.

OBJECTIVE: Hydroxychloroquine (HCQ) may prolong the QT interval, a risk factor for torsade de pointes, a potentially fatal ventricular arrhythmia. This study was undertaken to examine the cardiovascular safety of HCQ in patients with rheumatoid arthritis (RA). METHODS: We conducted an active comparator safety study of HCQ in a propensity score-matched cohort of 8,852 US veterans newly diagnosed as having RA between October 1, 2001 and December 31, 2017. Patients were started on HCQ (n = 4,426) or another nonbiologic disease-modifying antirheumatic drug (DMARD; n = 4,426) after RA diagnosis, up to December 31, 2018, and followed up for 12 months after therapy initiation, up to December 31, 2019. RESULTS: Patients had a mean ± SD age of 64 ± 12 years, 14% were women, and 28% were African American. The treatment groups were balanced with regard to 87 baseline characteristics. There were 3 long QT syndrome events (0.03%), 2 of which occurred in patients receiving HCQ. Of the 56 arrhythmia-related hospitalizations (0.63%), 30 occurred in patients in the HCQ group (hazard ratio [HR] associated with HCQ 1.16 [95% confidence interval (95% CI) 0.68-1.95]). All-cause mortality occurred in 144 (3.25%) and 136 (3.07%) of the patients in the HCQ and non-HCQ groups, respectively (HR associated with HCQ 1.06 [95% CI, 0.84-1.34]). During the first 30 days of follow-up, there were no long QT syndrome events, 2 arrhythmia-related hospitalizations (none in the HCQ group), and 13 deaths (6 in the HCQ group). CONCLUSION: Our findings indicate that the incidence of long QT syndrome and arrhythmia-related hospitalization is low in patients with RA during the first year after the initiation of HCQ or another nonbiologic DMARD. We found no evidence that HCQ therapy is associated with a higher risk of adverse cardiovascular events or death.

Association between lifetime risk of atrial fibrillation and mortality in the oldest old.

BACKGROUND: Age is the strongest predictor of atrial fibrillation (AF), yet little is known about AF incidence in the oldest old. HYPOTHESIS: AF incidence declines after age 90 years, and morbidity is compressed into a brief period at the end of life. METHODS: In this retrospective, longitudinal cohort study of patients (born 1905-1935), we examined cumulative lifetime incidence of AF and its impact on mortality. Data included records from 1 062 610 octogenarians, 317 161 nonagenarians, and 3572 centenarians. Kaplan-Meier curves were used to estimate cumulative incidence of AF by age group, incidence rates were compared using log-rank tests, and Cox proportional hazards model was used to estimate unadjusted hazard ratios. The primary outcome was AF incidence at age > 80 years; the secondary outcome was mortality. RESULTS: The cumulative AF incidence rate was 5.0% in octogenarians, 5.4% in nonagenarians, and 2.3% in centenarians. Octogenarians and nonagenarians had a higher risk of AF incidence compared to centenarians (adjusted hazard ratio 8.74, 95% confidence interval [CI]: 6.31-12.04; and 2.98, 95% CI: 2.17-4.1, respectively). The lowest hazard ratio for mortality in patients with AF compared to those without was 2.3 (95% CI: 2.3-2.4) in patients who were on antiplatelet and anticoagulant medication and had a score of 0 on the Elixhauser comorbidity index score. CONCLUSIONS: Although AF incidence increased with age, being a centenarian was associated with reduced incidence and compression of morbidity. Patients with AF had a higher adjusted mortality rate. However, data suggest that a regimen of anticoagulants and antiplatelets may reduce risk of mortality in patients over 80 with an AF diagnosis.

Similar clinical benefits from below-target and target dose enalapril in patients with heart failure in the SOLVD Treatment trial.

AIMS: To examine associations of below-target and target dose of enalapril, an angiotensin-converting enzyme (ACE) inhibitor, with outcomes in patients with heart failure and reduced ejection fraction (HFrEF) in the Studies of Left Ventricular Dysfunction (SOLVD) Treatment trial. METHODS AND RESULTS: Two thousand five hundred and sixty-nine patients with HFrEF (ejection fraction ≤35%) were randomized to below-target (5-10 mg/day) dose placebo (n = 1284) or enalapril (n = 1285). One month post-randomization, blind up-titration to target (20 mg/day) dose was attempted for both study drugs in 2458 patients. Among the 1444 patients who achieved dose up-titration (placebo, n = 748; enalapril, n = 696; mean dose for both groups, 20.0 mg/day), target dose enalapril (vs. target dose placebo) was associated with a 9% absolute lower risk of the combined endpoint of heart failure hospitalization or all-cause mortality [adjusted hazard ratio (HR) 0.70; 95% confidence interval (CI) 0.60-0.81; P < 0.001] during 4 years of follow-up. Among the 1014 patients who could not achieve target dose (placebo, n = 486; enalapril, n = 528; mean dose for both groups, 8.8 mg/day), below-target dose enalapril (vs. below-target dose placebo) was associated with a 12% absolute lower risk of the combined endpoint of heart failure hospitalization or all-cause mortality (adjusted HR 0.68; 95% CI 0.57-0.81; P < 0.001). Among the 1224 patients receiving enalapril, target (vs. below-target) dose had no association with the combined endpoint of heart failure hospitalization or all-cause mortality (adjusted HR 1.04; 95% CI 0.87-1.23; P = 0.695). CONCLUSION: In patients with HFrEF, the clinical benefits of ACE inhibitors appear to be similar at both below-target and target doses.

Time in Therapeutic Range, as a Determinant of All-Cause Mortality in Patients With Hypertension.

BACKGROUND: Accumulating evidence indicates that reducing systolic blood pressure (BP) to <140 mm Hg improves health outcomes; however, an optimal level has not yet been determined. Many population studies or post hoc analyses suggest a target systolic BP between 120 and 140 mm Hg with increased risk above and below that range. We tested the hypothesis that consistent control of systolic BP between 120 and 140 mm Hg-time in therapeutic range-is a strong determinant of all-cause mortality among US veterans. METHODS AND RESULTS: A total of 689 051 individuals from 15 Veterans Administration Medical Centers were followed over a 10-year period. Participants were classified as hypertensive, intermediate hypertensive, and normotensive according to the number of elevated BP recordings (>3, 1 or 2, and none, respectively). Time within, above, or below therapeutic range (120-140 mm Hg) was considered in quartiles and related to all-cause mortality. The study population consisted of 54% hypertensive, 19.9% intermediate, and 26.1% normotensive participants; the corresponding mortality rates for the 3 groups were 11.5%, 8%, and 1.9%, respectively (P<0.0001 for all comparisons). Mortality rates for hypertensive participants with BP consistently within, above, or below the therapeutic range were 6.5%, 21.9%, and 33.1%, respectively (P<0.0001 for all comparisons). Mortality rates in hypertensive participants increased from 6.5% in the most consistently controlled quartile (>75%) to 8.9%, 15.6%, and 23.5% towards the less consistently controlled quartiles (50-75%, 25-50%, and <25%, respectively; P<0.0001 for all comparisons). CONCLUSIONS: An inverse and gradual association between time in therapeutic range and all-cause mortality was observed in this large veteran cohort. Consistency of BP control over time is a strong determinant of all-cause mortality, and consistency of BP control should be monitored in everyday clinical practice.

Digoxin and 30-Day All-Cause Readmission in Long-Term Care Residents Hospitalized for Heart Failure.

BACKGROUND: Digoxin use has been shown to be associated with a lower risk of 30-day all-cause hospital readmissions in older patients with heart failure (HF). In the current study, we examined this association among long-term care (LTC) residents hospitalized for HF. METHODS: Of the 8049 Medicare beneficiaries discharged alive after hospitalization for HF from 106 Alabama hospitals, 545 (7%) were LTC residents, of which 227 (42%) received discharge prescriptions for digoxin. Propensity scores for digoxin use, estimated for each of the 545 patients, were used to assemble a matched cohort of 158 pairs of patients receiving and not receiving digoxin who were balanced on 29 baseline characteristics. Hazard ratios (HRs) and 95% confidence intervals (CIs) for outcomes associated with digoxin among matched patients were estimated using Cox regression models. RESULTS: Matched patients (n = 316) had a mean age of 83 years, 74% were women, and 18% African American. Thirty-day all-cause readmission occurred in 21% and 20% of patients receiving and not receiving digoxin, respectively (HR, 1.02; 95% CI, 0.63-1.66). Digoxin had no association with all-cause mortality (HR, 0.90; 95% CI, 0.48-1.70), HF readmission (HR, 0.90; 95% CI, 0.38-2.12), or a combined endpoint of all-cause readmission or all-cause mortality (HR, 0.97; 95% CI, 0.65-1.45) at 30 days. These associations remained unchanged at 1 year postdischarge. CONCLUSIONS: The lack of an association between digoxin and 30-day all-cause readmission in older nursing home residents hospitalized for HF is intriguing and needs to be interpreted with caution given the small sample size.

Systolic-diastolic hypertension versus isolated systolic hypertension and incident heart failure in older adults: Insights from the Cardiovascular Health Study.

BACKGROUND: Isolated systolic hypertension (ISH) is common in older adults and is a risk factor for incident heart failure (HF). We examined the association of systolic-diastolic hypertension (SDH) with incident HF and other outcomes in older adults. METHODS: In the Cardiovascular Health Study (CHS), 5776 community-dwelling adults≥65years had data on baseline systolic and diastolic blood pressure (SBP and DBP). We excluded those with DBP<60mmHg (n=821), DBP≥90 and SBP<140mmHg (n=28), normal BP, taking anti-hypertensive drugs (n=1138), normal BP, not taking anti-hypertensive drugs, history of hypertension (n=193), and baseline HF (n=101). Of the remaining 3495, 1838 had ISH (SBP≥140 and DBP<90mmHg) and 240 had SDH (SBP≥140 and DBP≥90mmHg). The main outcome was centrally-adjudicated incident HF over 13years of follow-up. RESULTS: Participants had a mean (±SD) age of 73 (±6)years, 57% were women, and 16% African American. Incident HF occurred in 25%, 22% and 11% of participants with ISH, SDH and no hypertension, respectively. Compared to no hypertension, multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for incident HF associated with ISH and SDH were 1.86 (1.51-2.30) and 1.73 (1.23-2.42), respectively. Cardiovascular mortality occurred in 22%, 24% and 9% of those with ISH, SDH and no hypertension, respectively with respective multivariable-adjusted HRs (95% CIs) of 1.88 (1.49-2.37) and 2.30 (1.64-3.24). CONCLUSION: Among older adults with hypertension, both SDH and ISH have similar associations with incident HF and cardiovascular mortality.

Cardiorespiratory Fitness and Incidence of Major Adverse Cardiovascular Events in US Veterans: A Cohort Study.

OBJECTIVE: To assess the association between exercise capacity and the risk of major adverse cardiovascular events (MACEs). PATIENTS AND METHODS: A symptom-limited exercise tolerance test was performed to assess exercise capacity in 20,590 US veterans (12,975 blacks and 7615 whites; mean ± SD age, 58.2±11.0 years) from the Veterans Affairs medical centers in Washington, District of Columbia, and Palo Alto, California. None had a history of MACE or evidence of ischemia at the time of or before their exercise tolerance test. We established quintiles of cardiorespiratory fitness (CRF) categories based on age-specific peak metabolic equivalents (METs) achieved. We also defined the age-specific MET level associated with no risk for MACE (hazard ratio [HR], 1.0) and formed 4 additional CRF categories based on METs achieved below (least fit and low fit) and above (moderately fit and highly fit) that level. Multivariate Cox models were used to estimate HR and 95% CIs for mortality across fitness categories. RESULTS: During follow-up (median, 11.3 years; range, 0.3-33.0 years), 2846 individuals experienced MACEs. The CRF-MACE association was inverse and graded. The risk for MACE declined precipitously for those with a CRF level of 6.0 METs or higher. When considering CFR categories based on the age-specific MET threshold, the risk increased for those in the 2 CFR categories below that threshold (HR, 1.95; 95% CI, 1.73-2.21 and HR, 1.41; 95% CI, 1.27-1.56 for the least-fit and low-fit individuals, respectively) and decreased for those above it (HR, 0.77; 95% CI, 0.68-0.87 and HR, 0.57; 95% CI, 0.48-0.67 for moderately fit and highly fit, respectively). CONCLUSION: Increased CRF is inversely and independently associated with the risk for MACE. When an age-specific MET threshold was defined, the risk for MACE increased significantly for those below that threshold and decreased for those above it (P<.001).

A Comprehensive Multimorbidity Index for Predicting Mortality in Intensive Care Unit Patients.

BACKGROUND: Accurate prediction of mortality for patients admitted to the intensive care units (ICUs) is an important component of medical care. However, little is known about the role of multimorbidity in predicting end of life for high-risk and vulnerable patients. OBJECTIVE: The aim of the study was to derive and validate a multimorbidity risk model in an attempt to predict all-cause mortality at 6 and 12 months posthospital discharge. METHODS: This is a retrospective, observational, clinical cohort study. Data were collected on 442,692 ICU patients who received care through the Veterans Administration between January 2003 and December 2013. The primary outcome was all-cause mortality at 6 and 12 months posthospital discharge. We divided the data into derivation (80%) and validation (20%) sets. Using multivariable logistic regression models, we compared prognostic models based on age, principal diagnosis groups, physiological markers, immunosuppressants, comorbidity categories, and a newly developed multimorbidity index (MMI) based on 5695 comorbidities. The cross-validated area under the receiver operating characteristic curve (AUC) was used to report the accuracy of predicting all-cause mortality at 6 and 12 months of hospital discharge. RESULTS: The average age of patients was 68.87 years (standard deviation = 12.1), 95.9% were males, 44.9% were widowed, divorced, or separated. The relative order of accuracy in predicting mortality was the MMI (AUC = 0.84, CI = 0.83-0.84), VA Inpatient Evaluation Center index (AUC = 0.80, CI = 0.79-0.81), principal diagnosis groups (AUC = 0.74, CI = 0.73-0.74), comorbidities (AUC = 0.69, CI = 0.68-0.70), physiological markers (AUC = 0.65, CI = 0.64-0.65), age (AUC = 0.60, CI = 0.60-0.61),and immunosuppressant use (AUC = 0.59, CI = 0.58-0.59). CONCLUSIONS: The MMI improved the accuracy of predicting short- and long-term all-cause mortality for ICU patients. Further prospective studies are needed to validate the index in different clinical settings and test generalizability of results in patients outside the VA system of care.

Higher risk for incident heart failure and cardiovascular mortality among community-dwelling octogenarians without pneumococcal vaccination.

AIMS: Octogenarians have the highest incidence of heart failure (HF) that is not fully explained by traditional risk factors. We explored whether lack of pneumococcal vaccination is associated with higher risk of incident HF among octogenarians. METHODS AND RESULTS: In the Cardiovascular Health Study (CHS), 5290 community-dwelling adults, ≥65 years of age, were free of baseline HF and had data on pneumococcal vaccination. Of these, 851 were octogenarians, of whom, 593 did not receive pneumococcal vaccination. Multivariable-adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for associations of lack of pneumococcal vaccination with incident HF and other outcomes during 13 years of follow-up were estimated using Cox regression models, adjusting for demographics and other HF risk factors including influenza vaccination. Octogenarians had a mean (±SD) age of 83 (±3) years; 52% were women and 17% African American. Overall, 258 participants developed HF and 662 died. Lack of pneumococcal vaccination was associated with higher relative risk of incident HF (aHR, 1.37; 95% CI, 1.01-1.85; P = 0.044). There was also higher risk for all-cause mortality (aHR, 1.23; 95% CI, 1.02-1.49; P = 0.028), which was mostly driven by cardiovascular mortality (aHR, 1.45; 95% CI, 1.06-1.98; P = 0.019). Octogenarians without pneumococcal vaccination had a trend toward higher risk of hospitalization due to pneumonia (aHR, 1.34; 95% CI, 0.99-1.81; P = 0.059). These associations were not observed among those 65-79 years of age. CONCLUSIONS: Among community-dwelling octogenarians, lack of pneumococcal vaccination was associated with a significantly higher independent risk of incident HF and mortality, and trend for higher pneumonia hospitalization.

Association of 30-Day All-Cause Readmission with Long-Term Outcomes in Hospitalized Older Medicare Beneficiaries with Heart Failure.

BACKGROUND: Heart failure is the leading cause for 30-day all-cause readmission. We examined the impact of 30-day all-cause readmission on long-term outcomes and cost in a propensity score-matched study of hospitalized patients with heart failure. METHODS: Of the 7578 Medicare beneficiaries discharged with a primary diagnosis of heart failure from 106 Alabama hospitals (1998-2001) and alive at 30 days after discharge, 1519 had a 30-day all-cause readmission. Using propensity scores for 30-day all-cause readmission, we assembled a matched cohort of 1516 pairs of patients with and without a 30-day all-cause readmission, balanced on 34 baseline characteristics (mean age 75 years, 56% women, 24% African American). RESULTS: During 2-12 months of follow-up after discharge from index hospitalization, all-cause mortality occurred in 41% and 27% of matched patients with and without a 30-day all-cause readmission, respectively (hazard ratio 1.68; 95% confidence interval 1.48-1.90; P <.001). This harmful association of 30-day all-cause readmission with mortality persisted during an average follow-up of 3.1 (maximum, 8.7) years (hazard ratio 1.33; 95% confidence interval 1.22-1.45; P <.001). Patients with a 30-day all-cause readmission had higher cumulative all-cause readmission (mean, 6.9 vs 5.1; P <.001), a longer cumulative length of stay (mean, 51 vs 43 days; P <.001), and a higher cumulative cost (mean, $38,972 vs $34,025; P = .001) during 8.7 years of follow-up. CONCLUSIONS: Among Medicare beneficiaries hospitalized for heart failure, 30-day all-cause readmission was associated with a higher risk of subsequent all-cause mortality, higher number of cumulative all-cause readmission, longer cumulative length of stay, and higher cumulative cost.

Renin-Angiotensin System Inhibition and Lower 30-Day All-Cause Readmission in Medicare Beneficiaries with Heart Failure.

BACKGROUND: Heart failure is the leading cause for 30-day all-cause readmission, the reduction of which is a goal of the Affordable Care Act. There is a growing interest in understanding the impact of evidence-based heart failure therapy on 30-day all-cause readmission. In the current study, we examined the impact of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACEI-ARBs) on 30-day all-cause readmission in heart failure. METHODS: Of the 1384 hospitalized Medicare beneficiaries with heart failure and left ventricular ejection fraction <45% discharged alive from 106 Alabama hospitals (1998-2001) without prior ACEI-ARB use and without known contraindications to ACEI-ARB use; 734 received new predischarge prescriptions for these drugs. Using propensity scores for ACEI-ARB initiation, we assembled a matched cohort of 477 pairs of patients balanced on 32 baseline characteristics (mean age 75 years, 46% women, 26% African American). RESULTS: Thirty-day all-cause readmissions occurred in 18% and 24% of matched patients receiving and not receiving ACEI-ARBs, respectively (hazard ratio [HR] 0.74; 95% confidence interval [CI], 0.56-0.97; P = .030). ACEI-ARB use was also associated with lower risk of 30-day all-cause mortality (HR 0.56; 95% CI, 0.33-0.98; P = .041) and of the combined endpoint of 30-day all-cause readmission or 30-day all-cause mortality (HR 0.73; 95% CI, 0.56-0.94; P = .017). All associations remained significant at 1 year post discharge. CONCLUSIONS: Among hospitalized patients with heart failure and reduced ejection fraction, the use of ACEI-ARBs was associated with a significantly lower risk of 30-day all-cause readmission and 30-day all-cause mortality; both beneficial associations persisted during long-term follow-up.

Causal Analysis of Emergency Department Delays.

BACKGROUND: Improvement teams make causal inferences, but the methods they use are based on statistical associations. This article shows how data and statistical models can be used to help improvement teams make causal inferences and find the root causes of problems. METHODS: This article uses attribution data, competing risk survival analysis, and Bayesian network probabilities to analyze excessive emergency department (ED) stays within one hospital. We use data recorded by ED clinicians that attributed the cause of excessive ED stays to 23 causes for the 70 049 ED visits between March 2011 and April 2014. We use competing risk survival analysis to identify contribution of each cause to the delay. We use Bayesian network models to analyze interaction among different causes of excessive stays and find the root causes of this problem. RESULTS: This article shows the utility of causal analysis to help improvement teams focus on the root causes of problems. For the example analyzed in the article, most causes for patients' excessive ED stays were related to the hospital operations outside the ED. Therefore, improvement projects inside the ED such as expanding ED, increasing staff at the ED, or improving operations are less likely to have a positive impact on reducing excessive ED stays. On the contrary, interventions that improve hospital occupancy (better discharge, expansion of beds, etc) or improve laboratory response times are more likely to result in positive outcomes.

SCD-HeFT: Use of R-R interval statistics for long-term risk stratification for arrhythmic sudden cardiac death.

BACKGROUND: In the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), a significant fraction of the patients with congestive heart failure ultimately did not die suddenly of arrhythmic causes. Patients with CHF will benefit from better tools to identify if implantable cardioverter-defibrillator (ICD) therapy is needed. OBJECTIVES: We aimed to identify predictor variables from baseline SCD-HeFT patients' R-R intervals that correlate to arrhythmic sudden cardiac death (SCD) and mortality and to design an ICD therapy screening test. METHODS: Ten predictor variables were extracted from prerandomization Holter data from 475 patients enrolled in the ICD arm of the SCD-HeFT by using novel and traditional heart rate variability methods. All variables were correlated to SCD using the Mann-Whitney-Wilcoxon test and receiver operating characteristic analysis. ICD therapy screening tests were designed by minimizing the cost of false classifications. Survival analysis, including log-rank test and Cox models, was also performed. RESULTS: A short-term fractal exponent, α1, and a long-term fractal exponent, α2, from detrended fluctuation analysis, the ratio of low- to high-frequency power, the number of premature ventricular contractions per hour, and the heart rate turbulence slope are all statistically significant for predicting the occurrences of SCD (P < .001) and survival (log-rank, P < .01). The most powerful multivariate predictor tool using the Cox proportional hazards regression model was α2 with a hazard ratio of 0.0465 (95% confidence interval 0.00528-0.409; P < .01). CONCLUSION: Predictor variables extracted from R-R intervals correlate to the occurrences of SCD and distinguish survival functions among patients with ICDs in SCD-HeFT. We believe that SCD prediction models should incorporate Holter-based R-R interval analysis to refine ICD patient selection, especially to exclude patients who are unlikely to benefit from ICD therapy.

Risk of Heart Failure and Death After Prolonged Smoking Cessation: Role of Amount and Duration of Prior Smoking.

BACKGROUND: According to the 2004 Surgeon General's Report on Health Consequences of Smoking, after >15 years of abstinence, the cardiovascular risk of former smokers becomes similar to that of never-smokers. Whether this health benefit of smoking cessation varies by amount and duration of prior smoking remains unclear. METHODS AND RESULTS: Of the 4482 adults ≥65 years without prevalent heart failure (HF) in the Cardiovascular Health Study, 2556 were never-smokers, 629 current smokers, and 1297 former smokers with >15 years of cessation, of whom 312 were heavy smokers (highest quartile; ≥32 pack-years). Age-sex-race-adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for centrally adjudicated incident HF and mortality during 13 years of follow-up were estimated using Cox regression models. Compared with never-smokers, former smokers as a group had similar risk for incident HF (aHR, 0.99; 95% CI, 0.85-1.16) and all-cause mortality (aHR, 1.08; 95% CI, 0.96-1.20), but former heavy smokers had higher risk for both HF (aHR, 1.45; 95% CI, 1.15-1.83) and mortality (aHR, 1.38; 95% CI, 1.17-1.64). However, when compared with current smokers, former heavy smokers had lower risk of death (aHR, 0.64; 95% CI, 0.53-0.77), but not of HF (aHR, 0.97; 95% CI, 0.74-1.28). CONCLUSIONS: After >15 years of smoking cessation, the risk of HF and death for most former smokers becomes similar to that of never-smokers. Although this benefit of smoking cessation is not extended to those with ≥32 pack-years of prior smoking, they have lower risk of death relative to current smokers.

Discharge Hospice Referral and Lower 30-Day All-Cause Readmission in Medicare Beneficiaries Hospitalized for Heart Failure.

BACKGROUND: Heart failure (HF) is the leading cause for hospital readmission. Hospice care may help palliate HF symptoms but its association with 30-day all-cause readmission remains unknown. METHODS AND RESULTS: Of the 8032 Medicare beneficiaries hospitalized for HF in 106 Alabama hospitals (1998-2001), 182 (2%) received discharge hospice referrals. Of the 7850 patients not receiving hospice referrals, 1608 (20%) died within 6 months post discharge (the hospice-eligible group). Propensity scores for hospice referral were estimated for each of the 1790 (182+1608) patients and were used to match 179 hospice-referral patients with 179 hospice-eligible patients who were balanced on 28 baseline characteristics (mean age, 79 years; 58% women; 18% non-white). Overall, 22% (1742/8032) died in 6 months, of whom 8% (134/1742) received hospice referrals. Among the 358 matched patients, 30-day all-cause readmission occurred in 5% and 41% of hospice-referral and hospice-eligible patients, respectively (hazard ratio associated with hospice referral, 0.12; 95% confidence interval, 0.06-0.24). Hazard ratios (95% confidence intervals) for 30-day all-cause readmission associated with hospice referral among the 126 patients who died and 232 patients who survived 30-day post discharge were 0.03 (0.04-0.21) and 0.17 (0.08-0.36), respectively. Although 30-day mortality was higher in the hospice referral group (43% versus 27%), it was similar at 90 days (64% versus 67% among hospice-eligible patients). CONCLUSIONS: A discharge hospice referral was associated with lower 30-day all-cause readmission among hospitalized patients with HF. However, most patients with HF who died within 6 months of hospital discharge did not receive a discharge hospice referral.

Heart failure prognosis: comorbidities matter.

BACKGROUND: Prior risk prediction models have included a selective group of broad comorbidities in scoring prognosis of heart failure (HF) patients. OBJECTIVE: We examined whether scoring a comprehensive set of comorbidities separately, could improve the performance and accuracy of predicting HF prognosis. METHODS: This is a cross-validated, longitudinal, retrospective, observational study. Data were collected on 602,050 unique HF patients, who received care through the Veterans Administration (VA) between October 1, 2006 and September 31, 2011. The dependent variable was mortality in six months. The independent variables were all International Classification of Disease (ICD) comorbidities, without grouping into broad disease categories. RESULTS: The area under the receiver-operating curve (AROC) for the multimorbidity (MM) index was 0.784 (95% confidence interval [CI]: 0.781-0.786). The MM index was significantly (alpha <0.05) more accurate than the Quan variant of the Charlson Index (AROC=0.656), the comorbidity categories within the Care Assessment of Need (CAN) Index (AROC=0.677), the von Walraven variant of the Elixhauser Index (AROC=0.639), chronological age (AROC=0.649), or ejection fraction (EF) (AROC=0.533). CONCLUSION: Inclusion of additional comorbidities improves the accuracy of HF prognostic indices. Future studies are needed to drive HF prognostic indices with the MM index as a component.