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Abstract: We studied 944 hospitalized heart failure patients 65 years and older to examine the impact of incident atrial fibrillation on mortality. Patients were categorized into four groups based on past medical history and admission electrocardiogram: (1) no (neither past nor current), (2) incident (newly diagnosed), (3) past and (4) chronic (past and current) atrial fibrillation. The primary outcome was 4-year all-cause mortality. Bivariate and multivariable Cox proportion hazards analyses were used to determine risk of all-cause mortality. In the multivariable model, we adjusted for various demographic and clinical covariates. Compared with patients who never had atrial fibrillation, those with incident atrial fibrillation had a 57% higher risk of death (unadjusted hazard ratio, 1.57; 95% confidence interval, 1.22–2.03). After adjustment for other covariates the association remained unchanged (adjusted hazard ratio, 1.41; 95% confidence interval, 1.08–1.83). Past or chronic atrial fibrillation was not associated with increased risk of death. [Copyright &y& Elsevier]

Background: Atrial fibrillation is common in older adults with heart failure. It is known to adversely affect outcomes. Aim: To examine the associations of atrial fibrillation with 4-year mortality and 30-day readmission in older adults hospitalized with heart failure. Methods: Patients were Medicare beneficiaries 65 years of age and older discharged with a primary diagnosis of heart failure. Baseline data were obtained by retrospective chart reviews and data on mortality and readmission were obtained from Medicare administrative files. Presence of atrial fibrillation was confirmed using electrocardiogram during hospital admission. Using Cox proportional hazards models we estimated bivariate and multivariable (adjusted for various patient and care covariates) hazards ratios (HR) and 95% confidence intervals (CI) for 4-year mortality and 30-day readmission of patients with atrial fibrillation compared with those without. Results: Patients (n=944) had a mean age (±S.D.) of 79 (±7) years, 61% were women, 18% African–Americans, 25% had atrial fibrillation by admission electrocardiogram, 64% died within 4 years, and 8% were readmitted. Patients with atrial fibrillation had a 52% increased risk of 4-year mortality (adjusted HR=1.52; 95%CI=1.11–2.07). Atrial fibrillation was also associated with higher risk of readmission (unadjusted HR=1.64; 95%CI=1.01–2.68). However, the association lost its statistical significance after adjustment for various patient and care variables (adjusted HR=2.09; 95%CI=0.94–4.65). Conclusion: Presence of atrial fibrillation was associated with significant increased risk of long-term mortality in older adults hospitalized with heart failure and was associated with a non-significant higher risk of hospital readmission. [Copyright &y& Elsevier]

Abstract: Background: Compared with serum potassium levels 4–5.5 mEq/L, those <4 mEq/L have been shown to increase mortality in chronic heart failure (HF). Expert opinions suggest that serum potassium levels >5.5 mEq/L may be harmful in HF. However, little is known about the safety of serum potassium 5–5.5 mEq/L. Methods: Of the 7788 chronic HF patients in the Digitalis Investigation Group trial, 5656 had serum potassium 4–5.5 mEq/L. Of these, 567 had mild hyperkalemia (5–5.5 mEq/L) and 5089 had normokalemia (4–4.9 mEq/L). Propensity scores for mild hyperkalemia were used to assemble a balanced cohort of 548 patients with mild hyperkalemia and 1629 patients with normokalemia. Cox regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for association between mild hyperkalemia and mortality during a median follow-up of 38 months. Results: All-cause mortality occurred in 36% and 38% of matched patients with normokalemia and mild hyperkalemia respectively (HR, 1.07; 95% CI, 0.90–1.26; P =0.458). Unadjusted, multivariable-adjusted, and propensity-adjusted HRs for mortality associated with mild hyperkalemia were 1.33 (95% CI, 1.15–1.52; P <0.0001), 1.16 (95% CI, 1.01–1.34; P =0.040) and 1.13 (95% CI, 0.98–1.31; P =0.091) respectively. Mild hyperkalemia had no association with cardiovascular or HF mortality or all-cause or cardiovascular hospitalization. Conclusion: Serum potassium 4–4.9 mEq/L is optimal and 5–5.5 mEq/L appears relatively safe in HF. Despite lack of an intrinsic association , the bivariate association of mild-hyperkalemia with mortality suggests that it may be useful as a biomarker of poor prognosis in HF. [ABSTRACT FROM AUTHOR]

Abstract: Background: Hypokalemia is common in heart failure (HF) and is associated with increased mortality. Potassium supplements are commonly used to treat hypokalemia and maintain normokalemia. However, their long-term effects on outcomes in chronic HF are unknown. We used a public-use copy of the Digitalis Investigation Group (DIG) trial dataset to determine the associations of potassium supplement use with outcomes using a propensity-matched design. Methods: Of the 7788 DIG participants with chronic HF, 2199 were using oral potassium supplements at baseline. We estimated propensity scores for potassium supplement use for each patient and used them to match 2131 pairs of patients receiving and not receiving potassium supplements. Matched Cox regression models were used to estimate associations of potassium supplement use with mortality and hospitalization during 40 months of median follow-up. Results: All-cause mortality occurred in 818 (rate, 1327/10,000 person-years) and 802 (rate, 1313/10,000 person-years) patients respectively receiving and not receiving potassium supplements (hazard ratio {HR} when potassium supplement use was compared with nonuse, 1.05; 95% confidence interval {CI}, 0.94–1.18; P =0.390). All-cause hospitalizations occurred in 1516 (rate, 4777/10,000 person-years) and 1445 (rate, 4120/10,000 person-years) patients respectively receiving and not receiving potassium supplements (HR, 1.15; 95% CI, 1.05–1.26; P =0.004). HRs (95% CI) for hospitalizations due to cardiovascular causes and worsening HF were respectively 1.19 (95% CI, 1.08–1.32; P =0.001) and 1.27 (1.12–1.43; P <0.0001). Conclusion: The use of potassium supplements in chronic HF was not associated with mortality. However, their use was associated with increased hospitalization due to cardiovascular causes and progressive HF. [Copyright &y& Elsevier]

Cardiovascular disease is the major cause of mortality in patients with end-stage renal disease (ESRD). This study examined the all-cause mortality in 3,698 patients with ESRD evaluated for kidney transplantation at our institution from 2001 to 2004. Mean age for the cohort was 48 ± 12 years, and 42% were women. Stress myocardial perfusion imaging was done in 2,207 patients (60%) and coronary angiography in 260 patients (7%). There were 622 deaths (17%) during a mean follow-up period of 30 ± 15 months. The presence and severity of coronary disease on angiography was not predictive of survival. Coronary revascularization did not impact survival (p = 0.6) except in patients with 3-vessel disease (p = 0.05). The best predictor of death was left ventricular ejection fraction, measured by gated myocardial perfusion imaging, with 2.7% mortality increase for each 1% ejection fraction decrease. In conclusion, left ventricular ejection fraction is a strong predictor of survival in patients with ESRD awaiting renal transplantation. Strategies to improve cardiac function or earlier renal transplantation deserve further studies. [Copyright &y& Elsevier]

Chronic kidney disease (CKD) is common and is associated with increased mortality in heart failure (HF). However, it is unknown whether the effect of CKD on mortality varies by left ventricular ejection fraction (LVEF). We evaluated the effect of CKD on mortality in patients with systolic (LVEF ≤45%) and diastolic (LVEF >45%) HF. Of the 7,788 patients in the Digitalis Investigation Group trial, 3,527 (45%) had CKD (estimated glomerular filtration rate <60 ml/min/1.73 m2). We calculated the propensity score for CKD for each patient, using a multivariate logistic regression model (c statistic 0.76, postmatch absolute standardized differences <5% for all 32 co-variates). We matched 2,399 pairs of patients with and without CKD with similar propensity scores. There were 757 (rate 1,049/10,000 person-years) and 882 (rate 1,282/10,000 person-years) deaths, respectively, in patients without and with CKD (hazard ratio 1.22, 95% confidence interval 1.09 to 1.36, p <0.0001). CKD-associated mortality was higher in those with diastolic HF (371 extra deaths/10,000 person-years, hazard ratio 1.71, 95% confidence interval 1.21 to 2.41, p = 0.002) than in systolic HF (214 extra deaths/10,000 person-years, hazard ratio 1.19, 95% confidence interval 1.07 to 1.32, p = 0.001), which was significant (adjusted p for interaction = 0.034). A graded association was found between CKD-related deaths and LVEF. The hazard ratios for CKD-associated mortality for the LVEF subgroups of <35%, 35% to 55%, and >55% were 1.15 (95% confidence interval 1.02 to 1.29), 1.35 (95% confidence interval 1.11 to 1.64), and 2.33 (95% confidence interval 1.34 to 4.06). In conclusion, CKD-associated mortality was higher in those with diastolic than systolic HF. Patients with diastolic HF should be evaluated for CKD, and the role of inhibitors of the renin-angiotensin system in these patients needs to be investigated. [Copyright &y& Elsevier]