Data from a long-running trial finds no increased rate of cancer among patients taking any blood pressure medication, alone or in combination, says a report in the Aug. 18 issue of The Lancet.
"The issue was whether people treated with certain drugs run a higher or lower risk of cancer. Our study found an absolute negative -- no increased risk in any group of patients," says study leader Dr. Lars H. Lindholm, professor of medicine at Umea University."He says the study was done because of scattered reports saying there might be an increased incidence of cancer in some people taking medication for hypertension -- high blood pressure. Those studies generally included a small number of patients who were diagnosed with cancer, he says.
The Swedish study used data on more than 6,600 patients taking a variety of medications in the STOP-Hypertension trial. Their cancer incidence rates were compared with those from the Swedish Cancer Registry, Lindholm says.
"No difference in cancer risk was seen between patients randomly assigned to conventional drugs, calcium antagonists or ACE inhibitors," the report says. "Thus, the general message to the practicing physician is that more attention should be given to getting the blood pressure down than to the risk of cancer."
The results of the study were predictable but nonetheless are welcome, says Dr. Richard A. Stein, chief of cardiology at the Brooklyn Medical Center and a spokesman for the American Heart Association.
"I don't think there has been any concern on our part that being treated for hypertension is associated with an increased risk of cancer," Stein says.
"Whenever you talk about rest-of-your-life medication, there is always a concern, and it is always great when studies come out to say there is no risk," Stein says.
Lindholm says a probable reason why some earlier studies suggested a link was the presence of confounding factors, for example reports about a possible higher incidence of breast cancer in women being treated for hypertension. In that case, the confounding factor appears to be obesity, which is associated with both an increased incidence of high blood pressure and of breast cancer, he says.
"In other studies, the link seems to be due to pure chance," Lindholm says.
What To Do
"The risk of drugs is trivial compared to the risk of leaving hypertension untreated," says Klein.