Among a large sample of Veterans Affairs health care patients with peripheral artery disease, researchers found African Americans were 43% more likely to lose a limb to amputation--and it is likely not because of socioeconomic or behavioral factors.
Peripheral artery disease (PAD) is more likely to get out of control and result in limb amputation in African Americans than Caucasian patients, researchers said today presenting a study at the American Heart Association’s Scientific Sessions 2016 in New Orleans, LA.
Like coronary artery disease (CAD) the condition also puts patients at higher risk for heart attack and stroke.
Shipra Arya, MD, a vascular surgeon at Emory University in Atlanta, GA and colleagues looked at a group of 208,194 patients with PAD of whom 16.2% were black and 82.5% were white. Nearly all (98.1%) were men.
All were in the Veterans Affairs database from 2003 to 2014.
Though demographic differences that resulted in different degrees of access to health care were found, even allowing for those, the black veterans had a 43% higher amputation risk than the white patients, Arya said.
The actual cause could be a sign of a “true biological difference” she said in an interview, possibly a tendency to have smaller branch blood vessels that could be more prone to PAD.
Or there could be a genetic difference resulting a different accumulation of plaque in the arteries.
“The VA is a rich data set and the physicians and the patients are both very engaged,” she said, so it will be possible to do future studies, including a microscopic tissue examination to look for clues into the phenomenon.
The study is important not just because limb loss can be devastating, but because PAD if treated early can be halted or slowed before causes major damage. That includes heart attack and stroke, events that people with PAD risk having.
Though the black patients were also more likely to be in zip codes with high rates of poverty and to have habits that put them at risk like smoking, diabetes, high blood pressure and high cholesterol, they were still more likely to need amputations than the white patients in the study with the same risk factors.
The good news is that PAD responds to treatment, particularly to walking. Thirty minutes three times a week is enough to get healthier, she said.
“You walk until you feel pain [in legs and feet] then you rest and walk a little more,” she said.
For more advanced PAD surgeons can use an endovascular approach “and just go into the artery and scoop it out,” she said.
But once there is pain at rest, or tissue loss, wounds or gangrene, the prognosis changes.
In early disease the risk of amputation is 1% but it will steadily rise by 1 % a year, she said. If it progresses to tissue loss, there is a 25% chance of amputation within two years.
Curiously she said, her PAD patients seem to be less likely to make lifestyle changes when told they are threatened with eventual amputation than heart patients with CAD are to take similar action when they are told they are at risk of a heart attack.
“Telling someone you might lose a leg doesn’t seem to be a deterrent,” she said.