Too Little Evidence on PAD Screening to Make Definitive Recommendation, Says USPSTF

The U.S. Preventive Services Task Force (USPSTF) has issued a draft recommendation statement indicating that current evidence is insufficient to assess the balance of benefits and harms of screening for peripheral artery disease (PAD) and cardiovascular disease (CVD) risk assessment using the ankle brachial index (ABI) in adults.

The recommendation applies to asymptomatic adults who have no known diagnosis of PAD, CVD, severe chronic kidney disease or diabetes.

USPSTF Co-vice Chair Michael LeFevre, M.D., M.S.P.H., of Columbia, Mo., told AAFP News Now that the task force concluded that evidence for screening for PAD using ABI in asymptomatic adults who have not been diagnosed as having CVD or diabetes is lacking, and, therefore, the balance of benefits and harms of screening asymptomatic adults cannot be determined. He also said the task force found no evidence indicating that screening for and treating PAD in asymptomatic patients leads to clinically important benefits.

"If you've got somebody who's on the line and might want to take cholesterol-lowering medications but isn't sure, or their risk is intermediate and you want to be sure, it's possible -- but we're not certain -- that some additional information might help you make a one-on-one decision with your individual patient. But across populations, we have no evidence to suggest that it's helpful," he said. "We just aren't sure yet."

The last time the USPSTF focused on screening for PAD, according to LeFevre, it did so solely with regard to detection and management of PAD.

"This time, we added screening for PAD as a way to screen for coronary artery disease and for preventing coronary artery disease events, rather than PAD symptoms," he said. "The gist of that is that this is a systemic disease, so if you find disease in the arteries of legs, does that need to be managed differently to prevent heart attack?

"So, for the most part, if family physicians are doing appropriate risk management to prevent heart attacks, you have to question whether or not your treatment is going to change based on what you find in legs."

LeFevre said he doesn't see himself changing how he approaches CVD prevention in his patients.

"Right now, even though the balance of benefits and harms is uncertain, it would be hard for me to imagine that there would be many circumstances in which my management of a patient to prevent coronary artery disease would be influenced by the results of this test," he said. "Of course, as often as not, it's not a question of whether the family physician decides to order (the test); instead, the patient comes in with results. The important question for the family physician to ask is: Do the results of this test help me to prevent heart disease in this patient?"

On a side note, LeFevre pointed out that development of the PAD recommendation statement represents the first time the USPSTF will have followed the full transparency process it initiated in 2007 from beginning to end.

"We posted our draft research plan and reached out to interest groups, and this is the first time we are posting the evidence report and the recommendation statement at the same time in draft form," he said. "Both the (draft) evidence report and the (draft) recommendation statement will be revised on the basis of public comment."

The draft recommendation statement is available for comment until April 15 at 5 p.m. EDT.

The AAFP Commission on Health of the Public and Science is reviewing the USPSTF draft recommendation and evidence report and will comment on the draft and make recommendations to the Academy's Board of Directors regarding any indicated changes in current AAFP policy.