SUNDAY, June 24, 2012 (HealthDay News) -- Millions of Americans take a low-dose aspirin each day to help protect their hearts, but a new study suggests the pill's benefit may not extend to some people with type 2 diabetes.
Heart disease and stroke are the leading causes of death among people with type 2 diabetes. The American Diabetes Association currently recommends low-dose aspirin therapy for people with the disease, but the new research found that more than half of people with type 2 diabetes were "aspirin resistant."
The researchers assessed aspirin resistance in nearly 150 men with an average age of 48 who had type 2 diabetes. Aspirin resistance was identified by measuring levels of a chemical called 11-dehydro-thromboxane beta-2 (11DhTx2), which is formed during the clotting process.
High levels of this chemical in the urine indicate resistance to aspirin and its anti-clotting benefits.
The team found that 53 percent of the diabetic patients were aspirin-resistant. They also found that 11DhTx2 levels were higher in patients who'd had diabetes for a longer time and who had higher urinary levels of a protein called micro albumin, an indicator of early kidney disease in people with diabetes.
There was no association between 11DhTx2 concentrations and insulin levels, insulin resistance or certain markers of inflammation, according to the study, which was scheduled to be presented Sunday at the Endocrine Society's annual meeting in Houston.
There was one surprise: Patients with higher blood-pressure readings and wider waistlines actually had lower 11DhTx2 levels compared to other patients -- suggesting that aspirin might work for them.
"These results provide new information about the factors associated with aspirin resistance," lead author Dr. Subhashini Yaturu, section chief of the Endocrinology and Metabolism Department at Stratton VA Medical Center in Albany, N.Y., said in an Endocrine Society news release.
"This may help doctors identify people who are likely to be aspirin resistant, so higher doses or different drugs can be prescribed to prevent blood clots," Yaturu added. "Further studies are required to clarify the appropriate dose of aspirin and/or other therapies for subjects with diabetes to prevent clots."
One expert found the results intriguing, but said it's premature to tell diabetics to quit their daily aspirin.
"Aspirin resistance is a growing concern, but until we have better ways to identify it in the office setting the current [American Diabetes Association] guidelines recommending low-dose aspirin therapy are reasonable," said Dr. Tracy Breen, director of diabetes care for North Shore-LIJ Health System in New Hyde Park, N.Y.
She said, however, that the study "is an example of where we are heading in the field of genomic medicine or personalized medicine -- the ability to truly tailor therapy to the individual in order to maximize positive effects of therapeutic agents [and minimize negative effects]."
Data and results presented at medical meetings should be viewed as preliminary until published in a peer-reviewed journal.
The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about type 2 diabetes.