Conducting economic evaluations alongside multinational clinical trials: toward a research consensus

Demand for economic evaluations in multinational clinical trials is increasing, but there is little consensus about how such studies should be conducted and reported. At a workshop in Durham, North Carolina, we sought to identify areas of agreement about how the primary findings of economic evaluations in multinational clinical trials should be generated and presented. In this paper, we propose a framework for classifying multinational economic evaluations according to (a) the sources of an analyst's estimates of resource use and clinical effectiveness and (b) the analyst's method of estimating costs. We review existing studies in the cardiology literature in the context of the proposed framework. We then describe important methodological and practical considerations in conducting multinational economic evaluations and summarize the advantages and disadvantages of each approach. Finally, we describe opportunities for future research. Delineation of the various approaches to multinational economic evaluation may assist researchers, peer reviewers, journal editors, and decision makers in evaluating the strengths and limitations of particular studies.     

Determinants of Diuretic Responsiveness and Associated Outcomes During Acute Heart Failure Hospitalization: An Analysis From the NHLBI Heart Failure Network Clinical Trials

Background

Poor response to loop diuretic therapy is a marker of risk during heart failure hospitalization. We sought to describe baseline determinants of diuretic response and to further explore the relationship between this response and clinical outcomes.

Incidence and prevalence of heart failure in elderly persons, 1994-2003

BACKGROUND: Recent analyses have presented conflicting evidence regarding the incidence and prevalence of heart failure in the United States. We sought to estimate the annual incidence and prevalence of heart failure and associated survival in elderly persons from January 1, 1994, through December 31, 2003. METHODS: We conducted a retrospective cohort study of 622,789 Medicare beneficiaries 65 years or older who were diagnosed as having heart failure between 1994 and 2003. The main outcome measures were incidence and prevalence of heart failure and survival following a heart failure diagnosis. RESULTS: The incidence of heart failure declined from 32 per 1000 person-years in 1994 to 29 per 1000 person-years in 2003 (P < .01). Incidence declined most sharply among beneficiaries aged 80 to 84 years (from 57.5 to 48.4 per 1000 person-years, P < .01) and increased slightly among beneficiaries aged 65 to 69 years (from 17.5 to 19.3 per 1000 person-years, P < .01). Although risk-adjusted mortality declined slightly from 1994 to 2003, the prognosis for patients diagnosed as having heart failure remains poor. In 2002, risk-adjusted 1-year mortality was 27.5%, more than 3 times higher than for age- and sex-matched patients. CONCLUSIONS: Although the incidence of heart failure has declined somewhat during the past decade, modest survival gains have resulted in an increase in the number of patients living with heart failure. Identifying optimal strategies for the treatment and management of heart failure will become increasingly important as the size of the Medicare population grows.     

Outcomes of cardiac surgery in patients > or = 80 years: results from the National Cardiovascular Network

OBJECTIVES: The purpose of this study was to evaluate characteristics and outcomes of patients age > or =80 undergoing cardiac surgery. BACKGROUND: Prior single-institution series have found high mortality rates in octogenarians after cardiac surgery. However, the major preoperative risk factors in this age group have not been identified. In addition, the additive risks in the elderly of valve replacement surgery at the time of bypass are unknown. METHODS: We report in-hospital morbidity and mortality in 67,764 patients (4,743 octogenarians) undergoing cardiac surgery at 22 centers in the National Cardiovascular Network. We examine the predictors of in-hospital mortality in octogenarians compared with those predictors in younger patients. RESULTS: Octogenarians undergoing cardiac surgery had fewer comorbid illnesses but higher disease severity and surgical urgency than younger patients. Octogenarians had significantly higher in-hospital mortality after cardiac surgery than younger patients: coronary artery bypass grafting (CABG) only (8.1% vs. 3.0%), CABG/aortic valve (10.1% vs. 7.9%), CABG/mitral valve (19.6% vs. 12.2%). In addition, they had twice the incidence of postoperative stroke and renal failure. The preoperative clinical factors predicting CABG mortality in the very elderly were quite similar to those for younger patients with age, emergency surgery and prior CABG being the powerful predictors of outcome in both age categories. Of note, elderly patients without significant comorbidity had in-hospital mortality rates of 4.2% after CABG, 7% after CABG with aortic valve replacement (CABG/AVR), and 18.2% after CABG with mitral valve replacement (CABG/MVR). CONCLUSIONS: Risks for octogenarians undergoing cardiac surgery are less than previously reported, especially for CABG only or CABG/AVR. In selected octogenarians without significant comorbidity, mortality approaches that seen in younger patients.