What is peripheral artery disease?
Walking more can help manage it
Peripheral artery disease (PAD) is a chronic condition in which arteries narrowed by plaque accumulation reduce blood flow to the legs (usually) and/or arms, especially during exertion. Symptoms include leg pain while moving about and sores. PAD predicts increased risk of death from cardiovascular disease. Lifestyle choices that can minimize PAD include Keep Moving and Eat Better.
Medical guidelines recommend supervised exercise in a clinical setting to increase walking ability for persons with PAD. Alas, few people with PAD participate in Medicare-funded, supervised walking programs. Plus, the dropout rate is high. Lack of interest in supervised exercise may reflect logistical difficulties (excessive distance to clinical sites, lack of appropriate equipment at those sites) and transient pain while exercising. It seems that relatively costly supervised, clinically based exercise programs provide few benefits. Could home-based walking programs, which eliminate logistical problems, provide better results?
Researchers in Oklahoma devised a home-based NEXT Step exercise program. A clinical trial of the Next Step program featured 180 patients with PAD randomized into one of three groups: 1) a 12-week home-based walking outside program, 2) a 12-week supervised, clinically based treadmill walking inside program, and 3) an attention-control 12-week program of light resistance training. All participants wore accelerometers, allowing the researchers to monitor participant activity levels and provide occasional feedback.
After 12 weeks, both the home-based and supervised, clinically based programs showed better results than the attention-control group. The home-based group showed greater increase in the 6-minute distance walked test than the supervised, clinically based group, an extra 45 vs. 10 meters. On the other hand, the supervised clinically based group had greater peak walking time (192 versus 110 seconds) and longer time to leg pain onset (170 versus 104 seconds) compared to the home-based group. In addition, the home-based group showed significant improvements in large artery elasticity and high-sensitivity C-reactive protein (a marker of inflammation), whereas the supervised, clinically based group did not. Both the home-based and supervised, clinically based groups had similar rates of program adherence and major adverse events. Thus, a home-based walking program may be an effective and practical alternative to a supervised, clinically based treadmill walking program to manage PAD.
A new study from UK researchers recruited 190 participants (average age 68 years) with PAD from six public hospitals in southwest England. Half of the participants were randomized to a largely home-based walking program, while half were allocated to usual care. A three-month walking program involved two, 60-minute in person sessions during weeks one and two followed by two, 20-minute phone calls during weeks 6 and 12 with physical therapists trained in motivational interviewing techniques. The sessions sought to 1) increase participant knowledge about PAD (its symptoms, causes, and treatments), 2) help participants understand their current walking abilities and challenges, 3) and identify strategies to overcome these challenges. Participants were instructed to walk 30 minutes each day on their own.
After three months, participants in the walking program showed statistically and clinically significant increases in the distance walked in six minutes (22.3 vs. 16.7 meters) compared to participants in the usual care control group. Walking may be a useful way to treat PAD, but long-term effects are not yet known. In any event, walking will likely produce other important benefits such as increased energy and reduced risk of dying from cardiovascular disease
Could a high-intensity home-based exercise program provide even better results? A team of researchers studied this question using data from a 12-month, randomized clinical trial with 305 participants with PAD at four clinical centers in the US. Participants were assigned to one of three groups: 1) high-intensity walking such that transient leg pain developed, 2) low-intensity walking such that no transient pain developed, and 3) a control group that received monthly health education information. All participants in the first two groups wore accelerometers to objectively determine walking intensity. The primary outcome of interest was the increase in the distance walked during a 6-minute period in a clinic.
At the end of 2 months, the high-intensity walking group showed statistically and clinically significant increases in the 6-minute walking distance compared to the low-intensity and control groups. In addition, the high-intensity group had significantly longer maximal effort treadmill walking time compared to the other two groups. This in spite of the high-intensity group meeting its walking intensity target less often than the low-intensity group, 63 vs. 92 percent. Thus, high-intensity walking may be an effective and possibly more attractive and lower-cost way to help manage PAD.
If you have peripheral artery disease, how about asking your medical provider for a referral to a home-based walking program? Walking more can do you a world of good.
