Results Summary

What was the research about?

Peripheral artery disease, or PAD, affects 8 million people in the United States. PAD narrows arteries in the legs. When this happens, the muscles don’t get enough oxygen-rich blood. People with PAD may have leg cramping, pain, or tiredness while walking or climbing stairs. Walking regularly for exercise may help reduce symptoms of PAD.

In this study, the research team created a program to help patients with PAD walk for exercise. Patients in the program walked at home and wore a Fitbit® activity tracker to record the number of steps walked per day. Trained coaches helped patients set walking exercise goals and record their activity on the study website. Patients also practiced walking with the coach. Coaches called patients regularly to check on their progress with the walking program.

The research team compared the walking ability of patients in the at-home walking exercise program with those who weren't in the program. Walking ability includes how far and fast people can walk and whether they have pain when walking. The team also looked at patients’ ability to carry out physical and social activities and how much pain interfered with their daily lives.

What were the results?

Patients in the program and those who weren't in the program didn’t differ in walking ability, physical function, or social activities. At the end of the study, patients in the at-home walking exercise program reported more pain than patients who weren’t in the program.

Who was in the study?

The study included 200 patients with PAD. Of these, 50 percent were African American, 47 percent were white, 2 percent reported other race, and 1 percent declined to provide information on race. The average patient age was 70, and 53 percent were women. Patients received care at clinics in three states.

What did the research team do?

The research team assigned patients by chance to one of two groups: the at-home walking exercise program plus usual care provided by their doctors, or usual care alone.

At the start of the study and nine months later, the research team tested how far patients could walk in six minutes. The team also asked all patients in the study to wear a device on their right hips for seven days to record patients’ rest and physical activity. Patients took surveys that asked about pain; physical and social function; and walking distance, speed, and stair climbing.

Doctors and patients with PAD helped the research team design the study and recruit people to be in the study.

What were the limits of the study?

Only 79 percent of patients in the at-home walking exercise program completed all follow-up calls. Results may have differed if more patients in the program had completed the calls.

Future research could look at other ways of helping patients with PAD find ways to walk for exercise.

How can people use the results?

Doctors can use the results when considering ways to help patients with PAD walk for exercise.

Final Research Report

View this project's final research report.

Peer-Review Summary

Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.

The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments. 

Peer reviewers commented, and the researchers made changes or provided responses. The comments and responses included the following:

  • Reviewers asked for a clearer picture of the depth and scope of feedback obtained from focus groups. Researchers said they did not record quantitative data from the focus groups nor did they perform a formal qualitative analysis of the discussions. The researchers revised the report to include more detail on the feedback obtained, and they noted the lack of quantitative analysis of focus group data as a study limitation.
  • Reviewers expressed curiosity about the fact that five people in the intervention group had leg revascularization treatment, while none of those in the control group did. The researchers responded that they did not anticipate this difference and agreed that this might have had the potential to bias the study in favor of the intervention group. Since the findings showed no benefit from the intervention, the researchers concluded that the different rates of lower extremity revascularization did not affect the conclusions.
  • Reviewers asked why the researchers added an accelerometer as a study outcome for Aim 2. The researchers explained that this decision was the result of two on-site stakeholder meetings, where participants decided to add a second objective outcome measure, in addition to the six-minute walk test.
  • Reviewers suggested that changing from a single-center study to a multicenter study should be noted as a limitation. The researchers addressed the issue in the revised report but disagreed that this change was a limitation, since they said multicenter trials are generally considered more generalizable and more valid than single-center trials. The researchers added that they discussed the switch with stakeholders, who agreed that it was important to reach the target sample size and complete the trial in a reasonable amount of time. Also, training was uniform across research sites.

Conflict of Interest Disclosures

Project Information

Mary McDermott, MD
Northwestern University
Patient-Centered Home Exercise Program for Peripheral Artery Disease

Key Dates

July 2014
April 2019

Study Registration Information


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Last updated: March 14, 2024