Popular Blood Pressure Medicine May Do More Harm Than Good
Pahor and Furberg say the calcium channel blockers were as effective at lowering blood pressure as the other medicines, but the findings suggest that the other drugs may offer some additional advantages over the calcium channel blockers in "the way they lower the blood pressure."
Pahor says many doctors believe that simply obtaining a reduction in blood pressure can predict the risk of future heart attacks or strokes. But, he says, even though calcium channel blockers do "lower the [blood pressure] number," the drugs may affect the body in other ways that "offset the benefit of a lowered blood pressure." Another possibility, he says, is that the other blood pressure-lowering agents, like beta-blockers, "offer some non-blood pressure action that by itself is protective."
Furberg says the findings provide clear evidence that calcium channel blockers should not be the first drug that patients get for their high blood pressure. "We now have a large body of evidence from large, randomized trials and the evidence speaks for itself," Furberg tells WebMD.
"Our recommendation is that [the other blood pressure-lowering medicines] ... diuretics, beta-blockers, and ACE-inhibitors, remain the clear choice for ... hypertension. Due to their clinical inferiority and high costs, calcium channel blockers should be considered when [other standard] drugs have failed or cannot be tolerated. A few large, ongoing trials may modify the findings, but it is unlikely they will reverse them," Furberg says.
Milton Packer, MD, says that before we assume that all calcium channel blockers are inferior to other antihypertensives, more studies need to be performed. "I think Dr. Furberg has presented data here today that raise a concern about the use of [calcium channel blockers]. The definitive answer is not in place ... I think this is the first step in an evolving process to find out what truly represents first ... therapy [for hypertension]." Packer, a professor of medicine at the Columbia University College of Physicians and Surgeons in New York, did not participate in the study.
Robert Temple, MD, associate director of medical policy at the FDA's Center for Drug Evaluation and Research, tells WebMD that the FDA does not plan any immediate action on long-acting calcium channel blockers.