In search of a heart drug for diabetics
Heart disease is the bane of diabetics. Fully 80% of diabetics die of cardiovascular disease, and efforts to lower the risk by reducing blood pressure, lowering cholesterol and eliminating other risk factors have had minimal success. Only about 7% of diabetics are able to bring cardiac risk factors to desired levels.
One big problem is that drugs that lower blood pressure can be counterproductive, exacerbating diabetes as they reduce hypertension. The key class of drugs known as beta blockers, for example, has repeatedly been demonstrated to be more effective at lowering blood pressure in diabetics than in those without the disease. But beta blockers tend to raise blood sugar levels, slow the heart rate and increase levels of triglycerides, a form of cholesterol.
“Side effects are the big Achilles heel of beta blockers,” said Dr. George Bakris of Rush University Medical Center in Chicago.
But a study presented last week at a New Orleans meeting of the American Heart Assn. showed that one of the newest beta blockers, carvedilol, successfully lowers blood pressure without the side effects associated with other beta blockers. The results were also reported Wednesday in the Journal of the American Medical Assn.
Bakris and his colleagues studied 1,235 Type 2 diabetics with hypertension who were receiving conventional diabetes therapy, along with either ACE inhibitors or angiotension II receptor blockers to reduce their hypertension. All still had above-normal blood pressure, however.
Half the patients received carvedilol, sold by GlaxoSmithKline under the brand name Coreg, and half received an older beta blocker called metoprolol. Both groups of patients achieved their desired blood pressure, although it took higher doses of metoprolol than is normally prescribed.
But patients receiving carvedilol showed no increase in their blood sugar levels, while those receiving metoprolol had an average 13% rise. Those receiving carvedilol had a 9% drop in insulin resistance; those receiving the other drug had no drop.
The drug could be regularly prescribed to the 18 million Americans who suffer from diabetes and high blood pressure “without the added baggage of worrying about those other cardiovascular risk factors getting worse,” Bakris said.
Among other results presented at the meeting:
* American jobs are not the only thing being outsourced to India. So are clinical trials, , said Dr. Salim Yusuf of McMaster University in Ontario, Canada. He and his colleagues studied an inexpensive, blood-thinning agent on 15,000 heart attack patients in India and China, comparing it with a placebo.
They found that the drug, a member of the heparin family, reduced deaths, heart attacks and stroke by a minimum of 13% when given in conjunction with standard therapies. One advantage of conducting the study abroad was that patients could be hospitalized and monitored for seven days, which could not have been accomplished in North America because of the pressure to get patients out of the hospital quickly.
* The first study of cholesterol-lowering drugs called statins conducted exclusively on African Americans showed that a new drug called Crestor is more effective than the more commonly used Lipitor. The trial was the second major study to be conducted on blacks and reported at the heart meeting. The first was about a new combination drug, called BiDil, directed at blacks with advanced heart failure. Both reflect a growing interest in conducting trials in groups other than middle-aged white men. Statins were chosen for the second trial because an estimated 42% of African Americans have high cholesterol levels.
Dr. Keith Ferdinand of Heartbeats Life Center in New Orleans and his colleagues studied 774 men and women. After six weeks, Crestor lowered the level of so-called bad cholesterol by 46%; Lipitor lowered it 39%.
* Women suffering a heart attack do not get to the hospital as quickly as men and, once there, do not receive treatment as quickly, said a study by Dr. Mauro Moscucci of the University of Michigan and a colleague.
In a study of 1,551 heart attack patients who had emergency angioplasty, they found that men reached the emergency room in an average of 85 minutes, compared with 105 minutes for women -- who often don’t recognize the symptoms as quickly. Once there, treatment began within 105 minutes for men, compared with 118 minutes for women.
As a consequence, one in 13 women in the study died, compared with one in 32 men.