Supervised Exercise Therapy for Symptomatic Peripheral Artery Disease: A REVIEW OF CURRENT EXPERIENCE AND PRACTICE-BASED RECOMMENDATIONS

Socioeconomic factors predict successful supervised exercise therapy completion

OBJECTIVE

Supervised exercise therapy (SET) for patients with intermittent claudication (IC) can lower the risk of progression to chronic limb-threatening ischemia and amputation, while preserving and restoring functional status. Despite supporting evidence, it remains underutilized, and among those who initiate programs, attrition rates are extremely high. We hypothesize that socioeconomic factors may represent significant barriers to SET completion.

METHODS

Patients with IC referred to SET at a multi-hospital, single-institution health care system (2018-2022) from a prospectively maintained database were retrospectively analyzed. Our primary endpoint was SET program completion and graduation, defined as completion of 36 sessions. Our secondary endpoints were vascular intervention within 1 year of referral and change in ankle-brachial index (ABI). Baseline demographics were assessed using standard statistical methods. Predictors of SET graduation were analyzed using multivariable logistic regression generating adjusted odds ratios (aORs) with 95% confidence intervals (CIs). Change in ABI was analyzed using t-test between subgroups. Reasons for attrition were tabulated. Patient Health Questionnaire-9 (PHQ-9), metabolic equivalent level, Vascular QOL, Duke Activity Status, and ABI were analyzed using paired t-tests across the entire cohort.

RESULTS

Fifty-two patients met inclusion criteria: mean age 67.85 ± 10.69 years, 19 females (36.54%), mean baseline ABI of 0.77 ± 0.16. The co-pays for 100% of patients were fully covered by primary and secondary insurance plans. Twenty-one patients (40.38%) completed SET. On multivariable analysis, residence in a ZIP code with median household income <$47,000 (aOR, 0.10; 95% CI, 0.01-0.76; P = .03) and higher body mass index (aOR, 0.81; 95% CI, 0.67-0.99; P = .04) were significant barriers to SET graduation. There were no differences in ABI change or vascular intervention within 1 year between graduates and non-graduates. Non-graduates reported transportation challenges (25.00%), lack of motivation (20.83%), and illness/functional limitation (20.83%) as primary reasons for SET attrition. Metabolic Equivalent Level (P ≤ .01) and Duke Activity Status scores (P = .04) were significantly greater after participating in a SET program.

CONCLUSIONS

Although SET participation improves lower extremity and functionality outcomes, only 40% of referred patients completed therapy in our cohort. Our findings suggest that both socioeconomic and functional factors influence the odds of completing SET programs, indicating a need for holistic pre-referral assessment to facilitate enhanced program accessibility for these populations.

Uptake and outcomes of supervised exercise therapy for peripheral artery disease: The importance of vascular medicine specialists at a large midwestern health care system during the first 5 years of CMS reimbursement

BACKGROUND

Supervised exercise therapy (SET) is the cornerstone of medical therapy for symptomatic peripheral artery disease (PAD). Despite the efficacy of SET, initial reports following the 2017 Centers for Medicare and Medicaid Services (CMS) reimbursement decision indicate low SET uptake, referral, and completion. Vascular medicine specialists are key to the success of such programs. We examined rates of SET referral, completion, and outcomes in a health system with a robust SET program during the first 5 years of CMS reimbursement.

METHODS

A retrospective chart review of patients with PAD referred to SET between October 1, 2017 and December 31, 2022 was conducted. Patient demographic and medical characteristics, SET indication, referring provider specialty, SET participation (e.g., exercise modality, number of sessions, treadmill prescription), and outcomes were abstracted. Descriptive statistics, t-tests, and multiple linear regression were used to examine the sample, evaluate outcomes, and explore outcomes by relevant covariates (i.e., age, sex, referring provider specialty).

RESULTS

Of 5320 patients with PAD, N = 773 were referred to SET; N = 415 enrolled and were included in the present study. Vascular medicine and vascular surgery specialists were the two primary sources of referrals (30.6% and 51.6%, respectively). A total of 207 patients (49.9%) completed SET. Statistically significant and clinically meaningful improvements were observed in all outcomes.

CONCLUSION

SET referral and completion rates are low in the 5 years following CMS reimbursement, despite the advocacy of vascular medicine specialists. SET is effective in improving patient functional capacity and quality of life. Additional efforts are needed to increase both SET availability and referrals as part of comprehensive treatment of PAD.

Pre-participation Withdrawal and Noncompletion of Cardiac Rehabilitation in Peripheral Artery Disease: MATCHED COMPARISONS TO CORONARY ARTERY DISEASE

PURPOSE

Despite the mortality benefit of cardiac rehabilitation (CR) participation, as well as its cost-effectiveness for people with peripheral artery disease (PAD), there are limited data on adherence and completion of CR in those with and without concomitant coronary artery disease (CAD). The objective of this study was to compare CR pre-participation withdrawal and noncompletion between patients with PAD and concomitant PAD and CAD (PAD/CAD) versus matched and unmatched patients with CAD (uCAD).

METHODS

Consecutively referred patients between 2006-2017 with PAD (n = 271) and PAD/CAD (n = 610) were matched to CAD by age, sex, diabetes, smoking status, and referral year. The uCAD (n = 14 487) group was included for comparison. Reasons for withdrawal were ascertained by interview.

RESULTS

There were no significant differences in pre-participation withdrawal between PAD and matched CAD (46 vs 43%, P = .49), nor in noncompletion (22 vs 18%, P = .28). Results were similar for PAD/CAD and matched CAD (withdrawal: 36 vs 34%, P = .37) and (noncompletion: 25 vs 23%, P = .46). A smaller proportion of patients with uCAD withdrew (28%) than patients with PAD ( P < .001) and PAD/CAD ( P < .001), with no difference in noncompletion ( P > .40, both). There were no differences between PAD and PAD/CAD and their matched counterparts for medical and nonmedical reasons for withdrawal and noncompletion ( P ≥ .25, all).

CONCLUSION

Pre-participation withdrawal rates were similar between patients with PAD, PAD/CAD, and their matched cohorts but greater than patients with uCAD. Once patients started CR, there were similar completion rates among all groups. Reports that patients with PAD are less likely to start CR may be related to their complex medical profile rather than PAD alone. Strategies to improve participation among patients with PAD should focus on the immediate post-referral period.

Exercise Training for Patients With Peripheral Arterial Occlusive Disease

BACKGROUND

One-third of all persons with peripheral arterial occlusive disease (PAOD) suffer from intermittent claudication. Exercise training under appropriate supervision is recommended in the pertinent guidelines, but physicians order it too rarely, and so-called vascular exercise groups are not available everywhere. This situation needs improvement in view of the impor - tance of walking ability and cardiorespiratory fitness for patients' quality of life and long-term disease outcome.

METHODS

We review the scientific evidence on exercise training and on ways to lower barriers to the ordering of exercise training and to patient participation, on the basis of pertinent articles retrieved by a search of PubMed and in specialized sports science journals.

RESULTS

10 meta-analyses, 12 randomized controlled trials (RCTs), and 7 cohort studies were considered for this review. Largescale cohort studies have shown that exercise is associated with a lower risk of death (relative risk 0.65-0.78 after 12 months of exercise training, compared to an inactive lifestyle). Exercise training also improves the maximal walking distance by a mean of 136 m (training at home) or 180-310 m (supervised training). An additional improvement by a mean of 282 m can be expected from a combination of exercise training and endovascular revascularization. Further behavior-modifying interventions, such as goal-setting, planning, and feedback, increase both the maximum walking distance and the weekly duration of exercise.

CONCLUSION

Exercise improves walking ability and lowers mortality. To attract patients with intermittent claudication to exercise training, a broad assortment of analog, digital and telemetric tools and a dense network of vascular exercise groups should be made available, along with regular contact between physicians and patients.

Clinical Effectiveness of a Supervised Exercise Therapy Program for Treatment of Peripheral Artery Disease: A Translational Study

PURPOSE

National guidelines for the treatment and management of symptomatic peripheral artery disease (PAD) recommend supervised exercise therapy (SET) as a first line of therapy. However, it is unknown how these expert opinion-based SET guidelines work in clinical practice as SET programs become established following the 2017 Centers for Medicare & Medicaid Services coverage announcement. The purpose of this prospective, nonrandomized translational study was to evaluate the clinical effectiveness of a SET program and specifically walking exercise modalities that did not incorporate a treadmill (TM).

METHODS

Participants enrolled in a 12-wk SET program housed in four rural Midwest cardiac rehabilitation settings and were prescribed an exercise program by an exercise physiologist or nurse based on current SET guidelines. Groups included TM walking, total body recumbent stepping (TBRS), TM walking + TBRS, and multimodal. Pre- and post-tests of walking capacity, physical function, and quality of life were administered.

RESULTS

The sample (n = 93) was all White, with 55% female representation, age of 73.7 ± 9.0 yr, and mild-moderate PAD (ankle-brachial index = 0.71 ± 0.19). Collectively, SET significantly improved the 6-min walk test (32.1 ± 6.6 m; P < .01). Within-group changes in the 6-min walk test were seen for all groups except the multimodal group; there were no significant between-group differences in change scores ( P = .30). No significant between-group changes were seen for the TM walking, TBRS, and TM walking + TBRS groups for physical function measures.

CONCLUSION

This study demonstrates the clinical effectiveness of SET programs following current guidelines and potential utilization of non-TM walking modalities in SET programs.

Longitudinal Pathways Between Physical Activity, Depression, and Perceived Stress in Peripheral Artery Disease

BACKGROUND

One-fifth of the patients with peripheral artery disease (PAD) experience depression and stress. Depression and stress may impact patients' abilities to be physically active, a key recommendation for supporting overall PAD management to improve symptoms and reduce the risk of cardiovascular events. We aimed to study interrelationships between 1-year longitudinal trajectories of depression, stress, and physical activity following a PAD diagnosis.

METHODS

Patients with new or worsening PAD symptoms enrolled at 10 US PORTRAIT study (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) vascular specialty clinics (CT, LA, MI, MO, NC, OH, and RI) were assessed at baseline, 3, 6, and 12 months between June 2, 2011 and December 3, 2015. Depressive symptoms were measured with the 8-item Patient Health Questionnaire, perceived stress with the 4-item Perceived Stress Scale and physical activity with items from the INTERHEART study. Path analysis was used to examine the longitudinal relationship between depression and physical activity and perceived stress and physical activity.

RESULTS

A total of 766 patients were included (mean age of 68.2 [±9.4] years; 57.7% male). Overall, 17.8% reported significant depressive symptoms, 36.0% experienced increased perceived stress, and 44.1% were sedentary upon PAD diagnosis. A decrease in physical activity preceded a rise in subsequent depressive symptoms (β ranges -0.45 [95% CI, -0.80 to -0.09]; -0.81 [95% CI, -1.19 to 0.42]) over the course of 1 year. Low physical activity scores at the initial presentation were followed by high perceived stress at 3 months (β=-0.44 [95% CI, -0.80 to -0.07]).

CONCLUSIONS

In symptomatic PAD, a decrease in physical activity was followed by an increased risk of depressive symptoms and perceived stress at subsequent intervals over the course of 1 year following PAD diagnosis and treatment. Integrated behavioral health approaches for PAD, addressing physical activity and managing depression or distress, are indicated as collective PAD treatment goals.

Selected Plant-Derived Polyphenols as Potential Therapeutic Agents for Peripheral Artery Disease: Molecular Mechanisms, Efficacy and Safety

Vascular diseases, such as peripheral artery disease (PAD), are associated with diabetes mellitus and a higher risk of cardiovascular disease and even death. Surgical revascularization and pharmacological treatments (mainly antiplatelet, lipid-lowering drugs, and antidiabetic agents) have some effectiveness, but the response and efficacy of therapy are overly dependent on the patient’s conditions. Thus, the demand for new cures exists. In this regard, new studies on natural polyphenols that act on key points involved in the pathogenesis of vascular diseases and, thus, on PAD are of great urgency. The purpose of this review is to take into account the mechanisms that lead to endothelium dysfunction, such as the glycoxidation process and the production of advanced glycation end-products (AGEs) that result in protein misfolding, and to suggest plant-derived polyphenols that could be useful in PAD. Thus, five polyphenols are considered, baicalein, curcumin, mangiferin, quercetin and resveratrol, reviewing the literature in PubMed. The key molecular mechanisms and preclinical and clinical studies of each selected compound are examined. Furthermore, the safety profiles of the polyphenols are outlined, together with the unwanted effects reported in humans, also by searching the WHO database (VigiBase).