Postdischarge international normalized ratio testing and long-term clinical outcomes of patients with heart failure receiving warfarin: findings from the ADHERE registry linked to Medicare claims.

BACKGROUND: Effective warfarin thromboprophylaxis requires maintaining anticoagulation within the recommended international normalized ratio (INR) range. INR testing rates and associations between testing and outcomes are not well understood. HYPOTHESIS: INR testing rates after hospitalization for acute decompensated heart failure are suboptimal, and testing is associated with lower risks of mortality and adverse clinical events. METHODS: We conducted a retrospective cohort study of patients who were long-term warfarin users and were hospitalized for heart failure, had a medical history of atrial fibrillation or valvular heart disease, and were enrolled in fee-for-service Medicare. INR testing was defined as ≥1 outpatient INR test within 45 days after discharge. Using Cox proportional hazards models, we examined associations between testing and all-cause mortality, all-cause readmission, and adverse clinical events at 1 year. RESULTS: Among 8558 patients, 7722 (90.2%) were tested. After 1 year, tested patients had lower all-cause mortality (23.5% vs 32.6%; P < 0.001) and fewer myocardial infarctions (2.0% vs 3.3%; P = 0.02). These differences remained significant after multivariable adjustment with hazard ratios of 0.72 (95% confidence interval [CI]: 0.63-0.84; P < 0.001) and 0.58 (95% CI: 0.41-0.83; P = 0.003), respectively. Differences in all-cause readmission, thromboembolic events, ischemic stroke, and bleeding events were not statistically significant. CONCLUSIONS: Postdischarge outpatient INR testing in patients with heart failure complicated by atrial fibrillation or valvular heart disease was high. INR testing was associated with improved survival and fewer myocardial infarctions at 1 year but was not independently associated with other adverse clinical events.

Outcomes associated with warfarin use in older patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device: findings from the ADHERE registry linked to Medicare claims.

BACKGROUND: Warfarin use and associated outcomes in patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device have not been described previously. HYPOTHESIS: We hypothesized that warfarin is underused and is associated with lower risks of mortality, thromboembolic events, and myocardial infarction. METHODS: Using data from a clinical registry linked with Medicare claims, we examined warfarin use at discharge and 30-day and 1-year Kaplan-Meier estimates of all-cause mortality and cumulative incidence rates of mortality, thromboembolic events, myocardial infarction, and bleeding events in patients 65 years or older, with a history of atrial fibrillation and a cardiovascular implantable electronic device admitted with heart failure between 2001 and 2006, who were naïve to anticoagulation therapy at admission. We compared outcomes between patients who were or were not prescribed warfarin at discharge and tested associations between treatment and outcomes. RESULTS: Of 2586 eligible patients in 252 hospitals, 2049 were discharged without a prescription for warfarin. At 1 year, the group discharged without warfarin had a higher mortality rate after discharge (37.4% vs 28.8%; P < 0.001) but similar rates of thromboembolism, myocardial infarction, and bleeding events. After adjustment, treatment with warfarin was associated with lower risk of all-cause death 1 year after discharge (hazard ratio: 0.76, 95% confidence interval: 0.63-0.92). CONCLUSIONS: Among older patients with heart failure and atrial fibrillation and a cardiovascular implantable electronic device, 4 of 5 were discharged without a prescription for warfarin. Warfarin nonuse was associated with a higher risk of death 1 year after discharge. Clin. Cardiol. 2011 DOI: 10.1002/clc.22064 Damon M. Seils, MA, Duke University, assisted with manuscript preparation. Mr. Seils did not receive compensation for his assistance apart from his employment at the institution where the study was conducted. This study was supported by a research agreement between Duke University and Janssen Pharmaceuticals. The authors have no other funding, financial relationships, or conflicts of interest to disclose.

Safety and effectiveness of antithrombotic strategies in older adult patients with atrial fibrillation and non-ST elevation myocardial infarction.

BACKGROUND: We aimed to study the comparative safety and effectiveness of various antithrombotic treatment strategies among older adults with non-ST elevation myocardial infarction (NSTEMI) and atrial fibrillation (AF). METHODS: Using the CRUSADE registry linked to longitudinal Medicare claims data, we examined NSTEMI patients aged ≥ 65 years with a concomitant diagnosis of AF. Multivariable Cox analysis was used to compare risk of rehospitalization for bleeding and a major cardiac composite end point of death, readmission for myocardial infarction, or stroke, according to discharge antithrombotic strategy. RESULTS: Among 7619 NSTEMI patients with AF, 29% were discharged on aspirin alone; 37%, on aspirin + clopidogrel; 7%, on warfarin alone; 17%, on aspirin + warfarin; and 10%, on warfarin + aspirin + clopidogrel. There was no difference in predicted stroke risk between groups. By 1 year, 12.2% of patients were rehospitalized for bleeding, and 33.1% had a major cardiac event. Relative to aspirin alone, antithrombotic intensification was associated with increased bleeding risk (aspirin + clopidogrel adjusted HR 1.22, 95% CI 1.03-1.46 and warfarin + aspirin HR 1.46, 95% CI 1.21-1.80). Patients treated with aspirin + clopidogrel + warfarin had the highest observed bleeding risk (HR 1.65, 95% CI 1.30-2.10). One-year risk of the major cardiac end point was similar between groups, although, relative to aspirin only, there was a trend toward lower risk for the warfarin + aspirin group (HR 0.88, 95% CI 0.78-1.00). CONCLUSIONS: Older NSTEMI patients with AF are at high risk for subsequent bleeding and major cardiac events. Increased antithrombotic management was associated with increased bleeding risk. Further investigation is needed to clarify whether these risks are counterbalanced by reduced thromboembolic events in this population.

Pharmacologic prophylaxis for venous thromboembolism and 30-day outcomes among older patients hospitalized with heart failure: an analysis from the ADHERE national registry linked to Medicare claims.

BACKGROUND: Hospitalized medically ill patients are at greater risk for venous thromboembolism (VTE). Although pharmacologic prophylaxis regimens have reduced VTE risk in medically ill patients, associations with early postdischarge adverse clinical outcomes among patients with heart failure are unknown. HYPOTHESIS: We hypothesized that patients receiving pharmacologic VTE prophylaxis during hospitalization for heart failure would have lower rates of postdischarge adverse clinical outcomes than patients not receiving prophylaxis. METHODS: Using data from the Acute Decompensated Heart Failure (ADHERE) registry linked to Medicare claims, we estimated 30-day postdischarge outcome rates for patients who received in-hospital subcutaneous heparin compared with patients who did not receive in-hospital VTE prophylaxis. We excluded patients who received warfarin or intravenous heparin. Outcomes included mortality, thromboembolic events, major adverse cardiovascular events, and all-cause readmission. We used propensity-score methods to estimate associations between VTE prophylaxis and each outcome. In a secondary analysis, we compared outcomes of patients receiving pharmacologic prophylaxis with unfractionated heparin (UFH) vs low-molecular-weight heparin (LMWH). RESULTS: Of 36 799 eligible patients in 265 hospitals, 12 169 (33%) received pharmacologic VTE prophylaxis during the hospitalization. In unadjusted analysis and after weighting by the inverse probability of treatment, VTE prophylaxis was not associated with 30-day postdischarge mortality, thromboembolic events, major adverse cardiovascular events, or all-cause readmission. There were no differences in outcomes between patients receiving UFH and those receiving LMWH. CONCLUSIONS: Pharmacologic VTE prophylaxis is provided to one-third of older patients hospitalized with heart failure. Treatment with LMWH or UFH did not have a statistically significant association with 30-day postdischarge outcomes.

Generalizability and longitudinal outcomes of a national heart failure clinical registry: Comparison of Acute Decompensated Heart Failure National Registry (ADHERE) and non-ADHERE Medicare beneficiaries.

BACKGROUND: Clinical registries are used increasingly to analyze quality and outcomes, but the generalizability of findings from registries is unclear. METHODS: We linked data from the Acute Decompensated Heart Failure National Registry (ADHERE) to 100% fee-for-service Medicare claims data. We compared patient characteristics and inpatient mortality of linked and unlinked ADHERE hospitalizations; patient characteristics, readmission, and postdischarge mortality of linked ADHERE patients to a random 20% sample of Medicare beneficiaries hospitalized for heart failure; and characteristics of Medicare sites participating and not participating in ADHERE. RESULTS: Among 135,667 ADHERE records for eligible patients ≥ 65 years, we matched 104,808 (77.3%) records to fee-for-service Medicare claims, representing 82,074 patients. Linked hospitalizations were more likely than unlinked hospitalizations to involve women and white patients; there were no meaningful differences in other patient characteristics. In-hospital mortality was identical for linked and unlinked hospitalizations. In Medicare, ADHERE patients had slightly lower unadjusted mortality (4.4% vs 4.9% in-hospital, 11.2% vs 12.2% at 30 days, 36.0% vs 38.3% at 1 year [P < .001]) and all-cause readmission (22.1% vs 23.7% at 30 days, 65.8% vs 67.9% at 1 year [P < .001]). After risk adjustment, modest but statistically significant differences remained. ADHERE hospitals were more likely than non-ADHERE hospitals to be teaching hospitals, have higher volumes of heart failure discharges, and offer advanced cardiac services. CONCLUSION: Elderly patients in ADHERE are similar to Medicare beneficiaries hospitalized with heart failure. Differences related to selective enrollment in ADHERE hospitals and self-selection of participating hospitals are modest.

Comparison of characteristics of treated and non-treated patients with Hepatitis C infection.

OBJECTIVES: This study compares the characteristics of treated and non-treated patients with Hepatitis C (HCV) infection. METHODS: Information on patient demographics, clinical data, and treatment regimens were collected from a retrospective medical record review of 998 patients diagnosed with HCV, representing a diverse geographic sample of 200 U.S. physicians including 130 gastroenterologists, 50 infectious disease physicians, and 20 hepatologists. A total of 551 patients were randomly selected and 447 were provided as an augmented sample in an intent-to-treat analysis based on treatment decisions. Pretreatment factors examined included age, gender, race, weight, HCV genotype, HCV viral load, serum ALT levels, liver biopsy results, cirrhosis, HIV co-infection, HBV co-infection, IV drug use, and insurance status. Univariate analyses were performed using Chi-squared or ANOVA tests. Factors that were significant in univariate analyses were entered into a multivariate logistic regression model with HCV treatment as the outcome variable. RESULTS: Of the 998 patients reviewed, 778 were treated for HCV and 220 were not treated. In univariate analyses, non-treated patients were more likely to be African American, HBV co-infected, HIV co-infected, IDUs, alcoholics, Medicaid insured, and were less likely to have had biopsies. The multivariate regression analysis demonstrated that performance of a liver biopsy, treatment with psychiatric medications (antidepressants and anxiolytics), and patient weight were independently associated with treatment, while Medicaid insurance and HIV co-infection were independently associated with a decreased likelihood of receiving HCV therapy. CONCLUSION: This study suggests that it is not the clinical stage of HCV infection but the patient's demographic characteristics and co-morbid conditions that impact the decision to initiate HCV therapy.

Review of cost-effectiveness studies of pegylated therapies for hepatitis C.

Hepatitis C virus is a worldwide public health problem and carries an increased economic burden that affects individuals, employers, insurers and health systems. Estimates suggest that by the year 2008, the yearly costs of hepatitis C virus will exceed US$1 billion. The authors conducted a literature search to identify studies on pharmacoeconomics and outcomes research for hepatitis C virus. According to the literature, the new standard for disease management is interferon-alpha, chemically linked with polyethylene glycol (pegylated interferon-alpha) as a monotherapy, or in combination with ribavirin. The authors reviewed a number of articles providing original research on outcomes related to pegylated therapies. Clinical outcomes and end points included sustained and early virologic response, disease progression, liver complications and mortality; economic outcomes included direct medical costs related to in- and outpatient costs, screening and diagnostics. Studies that consider health-related quality of life and fatigue were also identified. While most of the studies adopted Markov modeling to predict the likely outcomes and the effects of therapy, it is also important to consider indirect costs, such as productivity loss related to absenteeism. Future research on the use of pegylated interferons, weight-adjusted dosing of ribavirin, and the treatment of relapsers and nonresponders should provide valuable data that can be incorporated into cost-effectiveness studies.