Blog | Thursday, April 10, 2014

PADs impact exceeds that of many other cardiovascular conditions, expert says

Peripheral artery disease (PAD) has a bigger public health impact than many better known coronary vascular diseases, but awareness of symptoms and interventions lag behind, an expert said.

Medicine has made unbelievable progress in treating heart disease, said Alan T. Hirsch, MD, at his presentation on noncoronary vascular conditions here at Internal Medicine 2014. The technologies for screening, diagnosing and caring for heart disease are expensive—and used, he said.

He told his audience, “If I were to drop here and have an ST-segment elevation anywhere between the great blue seas of this country, likely my door-to-balloon time would be very fast, because we measure it, we pay for it and you’re good at it.”

Dr. Hirsch is a University of Minnesota professor and researcher who wears many hats, including primary care internal medicine, cardiology and vascular medicine. So he’s in a position to judge when he observes that patients who have family histories of PAD and amputations never see this information included as part of the family history in the medical record. In general, physicians generally don’t conduct an ankle-brachial index until severe claudication occurs.

He also notes that fellows get 1 hour a year of training about noncoronary disease, and 500 hours about heart disease.

Yet, PAD has more of an impact than atrial fibrillation or hypertension, and is the “highest risk, most costly, most impactful disease that no one cares for,” he said.

He related more metrics:
• Between 12 million to 15 million Americans have PAD;
• 1 in 4 adults over the age of 50 will develop it, even if they don’t smoke or have diabetes; and
• It costs more than twice as much as stroke or heart disease.

Dr. Hirsch advised internists to understand that the numbers are a clear benchmark for when to begin treatment. ABI greater than 1.4 is noncompressible; 1 to 1.4 is normal; 0.91 to 0.99 is borderline; and less than 0.9 is abnormal.

Then understand that there is no qualifying these values as “mild,” for example. There is no relationship between the ABI value and the severity of leg symptoms. An abnormal ABI doubles to quadruples mortality risk, and even a borderline value can double morality rates, Dr. Hirsch said.

“There’s no such thing as a slightly abnormal ABI,” he said. “That disrespects the patient’s future.”

The U.S. Preventive Services Task Force issued guidelines in 2011. While these are useful from a public health standpoint, Dr. Hirsch advised internists to use clinical judgment to be sensitive to warning signs. Focus on PAD management via smoking cessation, exercise, lipid management, blood pressure control, blood sugar control and use of medications.