Blood Pressure Drugs Counter Cancer?
Fewer Colon, Pancreatic, and Esophageal Cancers Seen in People Taking ACE Inhibitors
May 23, 2006 -- Certain cancers may be less common among people taking a
type of blood pressure drug called ACE inhibitors, new studies show.
"ACE" stands for angiotensin converting enzyme. ACE inhibitors widen
or dilate the blood vessels, lowering blood pressure and increasing blood flow.
The drugs are prescribed for high blood
pressurehigh blood pressure,
failureheart failure, heart
attackheart attack, diabetesdiabetes, and heart
diseaseheart disease prevention
in high-risk individuals.
The new studies -- presented in Los Angeles, at Digestive Disease Week 2006
-- showed fewer cancers of the colon, pancreas, and esophagus in people taking
However, researcher Vikas Khurana, MD, stresses that it's too early to start
using ACE inhibitors to ward off those cancers, or even to favor ACE inhibitors
in picking a high blood pressure drug.
Khurana works at the Overton Brooks VA Medical Center in Shreveport, La.
"Although our studies are very interesting they are still
case-controlled studies and should not be used for clinical decisions at this
time," Khurana told reporters, in a teleconference.
He notes that the data doesn't show the dose, duration, or specific drugs
that were used and doesn't make any recommendations for people who need drugs
to treat high blood pressure.
Treating high blood pressure is "a very specialized field," Khurana
says, adding that drug decisions "need to be made based on individual
patients and their cardiologist or general internist."
"What we're studying is whether we have additional benefits out of these
agents, and I think still we need more time and more research on this to change
any clinical decisions at this time," Khurana says.
Tracking Cancer, ACE Inhibitors.
Data covered 483,733 veterans cared for from October 1998 to June 2004 in
the South Central VA Health Care Network, which covers eight states in the
south-central U.S. More than 184,700 of those veterans were taking ACE
A total of 6,697 veterans had colon and rectal cancer, 475 had pancreatic cancer, and 659 had esophageal cancer.
Khurana and colleagues checked which veterans had been prescribed ACE
inhibitors before diagnosis with colon, esophageal, or pancreatic cancer. The
researchers also adjusted for factors that might influence cancer risk,
including age, race, gender, BMI (body mass index), smoking, alcohol use, diabetes, and statin
Statins are cholesterol-cutting drugs that may lower the risk of some
cancers. Khurana and colleagues had previously reported that statin users were
less likely to have certain cancers. In their new study they separated the
effects of ACE inhibitors and statins and found that ACE inhibitors were
associated with a reduced risk of colon, pancreatic, and esophageal
Risk Reduction Estimates
After crunching the numbers, the risk reduction in veterans taking ACE
inhibitors was 53% for colon cancer, 52% for pancreatic cancer, and 46% for
esophageal cancer, Khurana told reporters.
The data doesn't prove that ACE inhibitors were responsible for those
results. The figures simply tracked those three cancers and use of ACE
inhibitors prior to diagnosis with any of those three cancers.
"We can't take the database studies as the definitive answer. We need to
have randomized, placebo-controlled trials before we use these agents as
chemoprotective agents against cancer," Khurana says.
In randomized, placebo-controlled trials, researchers randomly assign people
to take either an active drug (ACE inhibitors, in this case) or a pill
containing no medicine (placebo). That wasn't done in this study; none of the
veterans was asked to take any drugs for the sake of research.
Khurana notes that he is on the speakers' bureau for AstraZeneca, which
makes drugs including ACE inhibitors.