ORLANDO – Peripheral artery disease constitutes “a health crisis that is largely unnoticed” by the public and all too often by physicians as well – but that’s all about to change, Dr. Mark A. Creager said in his presidential address at the American Heart Association scientific sessions.
In the coming months, look for rollout of major AHA initiatives on peripheral vascular disease. These programs grew out of a summit meeting of thought leaders in the field of vascular disease convened recently by the AHA in order to find ways to boost public awareness and improve the quality of care for patients with peripheral artery disease (PAD), venous thromboembolism, and aortic aneurysm.
Bruce Jancin/Frontline Medical news
Dr. Mark A. Creager
PAD is all too often thought of as a disease of the legs, when in fact it is a clinical manifestation of systemic atherosclerosis, Dr. Creager noted. PAD affects on estimated 200 million people worldwide. In the United States alone, it accounts for $20 billion per year in health care costs. The mortality risk in affected patients is two- to fourfold greater than in individuals without PAD. Moreover, the risk of acute MI, stroke, or cardiovascular death among patients with PAD exceeds that of patients with established cerebrovascular disease.
“Clearly the unrecognized epidemic of vascular disease requires our attention,” observed Dr. Creager, professor of medicine and director of the Heart and Vascular Center at Dartmouth-Hitchcock Medical Center in Lebanon, N.H.
Indeed, he made it clear that improved diagnosis and treatment of PAD will be a major AHA priority during his term as president. Noting that the annual rate of deaths due to cardiovascular disease and stroke has already dropped by 13.7% in the 5 years since the AHA set the ambitious goal of a 20% reduction by the year 2020, he emphasized that a critical element in getting the rest of the way there involves addressing peripheral vascular diseases more effectively.
Improved public awareness about PAD has to be a priority. One survey found that 75% of the public is unaware of PAD. It’s a condition which Dr. Creager and others have shown has its highest prevalence in Americans in the lowest income and educational strata, largely independent of traditional cardiovascular risk factors.
“Even physicians often fail to consider PAD, chalking up leg pain to age or arthritis. In one study, physicians missed the diagnosis of PAD half the time. And even when physicians diagnose PAD, they often don’t treat it adequately,” according to Dr. Creager.
The use of statins and antiplatelet therapy in patients with PAD each reduces the risk of MI, stroke, or cardiovascular death by about 25%. Yet when Dr. Creager and coworkers analyzed National Health and Nutrition Examination Survey data, they found only 19% of patients with PAD who didn’t have previously established coronary or cerebrovascular disease were on a statin, just 21% were on an ACE inhibitor or angiotensin receptor blocker, and 27% were on antiplatelet therapy (Circulation. 2011 Jul 5;124[1]:17-23).
Among patients with symptomatic PAD, studies have shown that supervised exercise training can double walking distance. That’s a major quality of life benefit, yet one that goes unconsidered if the diagnosis is missed. “It’s rarely instituted even with the diagnosis, largely because of the lack of reimbursement,” according to Dr. Creager.
He painted a picture of PAD as a field ripe with opportunities for improved outcomes.
“Our ability to diagnose and treat vascular diseases has never been greater. The field of vascular biology has virtually exploded in recent years,” he said. “I’d like to focus not only on the extent of this crisis, but also on the importance of using what we know to treat it and prevent it, and on the urgency of intensifying our research efforts to better understand it.”
In the diagnostic arena, optical coherence tomography, intravascular ultrasound, PET-CT, and contrast-enhanced MRI provide an unprecedented ability to image plaques and assess their vulnerability to rupture.
On the interventional front, innovative bioengineering has led to the development of drug-coated balloons and bioabsorbable vascular scaffolds with the potential to curb restenosis and preserve patency following endovascular treatment of critical lesions.
In terms of medical management, the novel, super-potent LDL cholesterol–lowering inhibitors of PCSK9 (proprotein convertase subtilisin-kexin type 9) will need to be studied in order to see if they have a special role in the treatment and/or prevention of PAD.
Roughly 2 decades ago, Dr. Creager and coinvestigators showed that endothelial function typically drops by 30% in our twenties and then in our thirties, and by 50% once we’re in our forties. A high research priority in PAD will be to learn how to more effectively prolong endothelial health and prevent vascular stiffness, he said.