Doctors reacting to a study that suggests some blood pressure drugs might increase the risk of a heart attack are urging patients to continue taking the medication until more is known.
The study, presented March 10 at an American Heart Association meeting, found that the drugs, called calcium channel blockers, were associated with a 60 percent increase in heart attack risk.
While the risk to any individual in the short term is small, the overall risk to the estimated 6 million Americans taking the drugs for an extended period is significant, said the author of the study, Dr. Bruce Psaty, an epidemiologist and internist at the University of Washington in Seattle.
Some doctors said the report’s conclusions were overstated. Others said the study was important and underscored the need for further research. One drug maker said it believes newer forms of the drugs, which weren’t in the study, are safe.
“It’s not going to change my prescribing pattern for calcium blockers,” said Dr. Michael Marmulstein, a cardiologist in private practice in Albany. “I’m not saying, ‘The heck with this study and I’m going to use them anyway.’ The decision has to be made on an individual basis, taking into account any one person’s health.”
The study “raises some interesting questions,” but does not necessarily mean that calcium blockers are dangerous, he said.
Many other doctors interviewed agreed. They said that many factors contribute to the decision to prescribe a particular drug, and the study, while interesting, is not enough by itself to change treatment patterns.
Doctors reported that some patients had stopped taking calcium blockers after hearing about the study. The doctors agreed that patients should continue to take their medication until they consult with their doctors.
“The frustration that all of us in the practice of medicine are encountering right now is that patients are alarmed,” said Dr. Vincent W. Dennis, chairman of the department of nephrology and hypertension at the Cleveland Clinic Foundation.
“If you have been put on these drugs, presumably for good reason, don’t panic,” said Dr. Norman Kaplan, a hypertension specialist and endocrinologist at the University of Texas Southwestern Medical School in Dallas.
Kaplan noted that the study was a “casecontrol” study. Researchers collected information on patients who had had heart attacks (cases) and others who hadn’t (controls). The researchers then examined records of medication use in each group and calculated the heart attack risks associated with various drugs. The study found only that patients taking calcium blockers were statistically more likely to have heart attacks. Such a study cannot actually prove that calcium blockers cause heart attacks, Kaplan said.