β-Blocker Trials Seem to Be in Conflict
Two studies of β-blockers in the same issue of the New England Journal of Medicine seem to have conflicting conclusions, but the differences could result from the alternate effects of the drugs studied (N Engl J Med. 2001;344:1659–1667 and N Engl J Med. 2001;344:1651–1658).
The studies were performed in patients with advanced chronic heart failure, whereas previous β-blocker studies concentrated on patients with mild to moderate heart failure. The first study, the Beta-Blocker Evaluation of Survival Trials (BEST), compared the investigational drug bucindolol with placebo in a randomly assigned group of 2708 patients designated as New York Heart Association functional class III or IV who had ejection fractions ≤35%. The end point of the study was death from any cause. Interim analyses were performed, and the Data Safety and Monitoring Board recommended ending the study at the seventh such period because no difference in mortality had been identified.
In the second study, researchers randomly assigned 1133 patients to placebo and 1156 patients to treatment with the β-blocker carvedilol. In this study, 190 patients in the placebo group died compared with 130 in the carvedilol group, a 35% decrease in the risk of death with the β-blocker. The researchers concluded that treatment with carvedilol had benefit in this population, although “the mechanisms by which carvedilol reduces mortality among patients with heart failure remain unclear.” The group, which was led by Milton Packer, MD, of the College of Physicians and Surgeons at Columbia University in New York, noted that although carvedilol and bucindolol will both block β1 receptors, the latter drug did not have a favorable effect on mortality. “How can this difference be explained?” they asked. They theorize that the additional properties of carvedilol, such as α-adrenergic blockade, antioxidant activity, and antiendothelin effects may account for the differences in the patients with severe heart failure.
In an accompanying editorial (N Engl J Med. 2001;344:1711–1712), Eugene Braunwald, MD, of Brigham and Women’s Hospital in Boston, noted that at first, the 2 studies seem to have opposite conclusions. However, “differences among the β-blockers studied in these trials should also be noted. Metoprolol and bisoprolol are both β1-receptor–selective agents, whereas bucindolol and carvedilol are nonselective agents with vasodilator properties. Carvedilol also has an affinity for α1-receptors and possesses antioxidant and antiendothelin properties. Because of its potent β2-receptor–blocking activity, bucindolol also blocks the release of norepinephrine and thus exerts a profound sympatholytic response, which may limit its efficacy.”
“When the 2 new trials reported here are considered along with the previous studies, it is clear that β-blockers represent another important arrow in the physician’s quiver for the management of heart failure,” Braunwald wrote. However, the contraindications for the drugs, including reactive airway disease, sinus-node dysfunction, and abnormalities of the cardiac conduction system, along with the potential effects of the adrenergic nervous system’s role in supporting the heart’s circulation, make prescribing these drugs a difficult problem that should be approached cautiously with slow dose escalation, particularly in patients with severe heart failure. Dr Braunwald also chaired the Data Safety and Monitoring Board for the BEST trial.
Participation Deadline Extended 10 Weeks for Medicare Managed Care Organizations
Managed care plans have been given a 10-week extension on their deadline to decide whether they will continue to participate in the Medicare+Choice program and in what areas. In a May 29, 2001, announcement, the Bush administration said the extra time will allow the managed care programs to analyze cost data and other information crucial to determining their continued participation in the program.
In the year 2000, 118 such plans had announced that they would either withdraw from the Medicare program or leave areas of the country where such programs had proved unprofitable. Their decisions affected nearly 1 million Medicare beneficiaries, according to experts from the Health Care Financing Administration.
Enrolling seniors in the managed care plans has been a major focus of cost-cutting programs for the Medicare program and has been endorsed by both Democratic and Republican administrations. However, the decision to extend the managed care organizations’ deadline will make it more difficult for beneficiaries to find new coverage if the managed care programs to which they belong decide to leave the market.
Christopher Reeve and 7 Scientists Sue Bush Administration Over Lagging Stem Cell Funds
A federal lawsuit filed by paralyzed actor Christopher Reeve and 7 scientists accuses the Bush Administration of doing “irreparable harm” by withholding funds for stem cell research and delaying the development of life-saving therapies, according to the May 31, 2001, issue of the St Paul Pioneer-Press (Minnesota).
The Bush administration has halted the implementation of rules proposed for such research by the National Institutes of Health and subsequent funding while it reviews the issue. President Bush has indicated opposition to such research, although Health and Human Services Secretary Tommy Thompson has been equivocal on the subject. Secretary Thompson was governor of Wisconsin when scientists there first isolated the embryonic pluripotent stem cells. Mr Reeve has been a proponent of the stem cell research since he was paralyzed in a horse-riding accident.
Retirees Now Less Likely to Have Employer-Based Insurance
Although 70% of those who retired in the early 1980s had some kind of retiree health benefits, fewer than half of such former employees now enjoy that kind of protection, according to a report by the federal General Accounting Office (GAO).
The GAO estimates that 37% of early retirees aged 55 to 64 years have employer-based coverage, and only 26% of Medicare-eligible retirees receive such benefits. The GAO report predicted that the trend will continue because the cost of health premiums is rising greater than the inflation rate, the economy is slowing, changes in Medicare have been proposed, and the number of retirees in increasing. The GAO report is located at http://www.gao.gov
- Copyright © 2001 by American Heart Association