Tracie C. Collins

Supervised Exercise Versus Primary Stenting for Claudication Resulting From Aortoiliac Peripheral Artery Disease Six-Month Outcomes From the Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) Study

Background— Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise (SE), or stent revascularization (ST). Methods and Results— We randomly assigned 111 patients with aortoiliac peripheral artery disease to receive 1 of 3 treatments: optimal medical care (OMC), OMC plus SE, or OMC plus ST. The primary end point was the change in peak walking time on a graded treadmill test at 6 months compared with baseline. Secondary end points included free-living step activity, quality of life with the Walking Impairment Questionnaire, Peripheral Artery Questionnaire, Medical Outcomes Study 12-Item Short Form, and cardiovascular risk factors. At the 6-month follow-up, change in peak walking time (the primary end point) was greatest for SE, intermediate for ST, and least with OMC (mean change versus baseline, 5.8±4.6, 3.7±4.9, and 1.2±2.6 minutes, respectively; P <0.001 for the comparison of SE versus OMC, P =0.02 for ST versus OMC, and P =0.04 for SE versus ST). Although disease-specific quality of life as assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire also improved with both SE and ST compared with OMC, for most scales, the extent of improvement was greater with ST than SE. Free-living step activity increased more with ST than with either SE or OMC alone (114±274 versus 73±139 versus −6±109 steps per hour), but these differences were not statistically significant. Conclusions— SE results in superior treadmill walking performance than ST, even for those with aortoiliac peripheral artery disease. The contrast between better walking performance for SE and better patient-reported quality of life for ST warrants further study. Clinical Trial Registration— URL: . Unique identifier: [NCT00132743][1]. # Clinical Perspective {#article-title-36} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00132743&atom=%2Fcirculationaha%2F125%2F1%2F130.atomBackground Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise or stent revascularization.Background— Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise (SE), or stent revascularization (ST). Methods and Results— We randomly assigned 111 patients with aortoiliac peripheral artery disease to receive 1 of 3 treatments: optimal medical care (OMC), OMC plus SE, or OMC plus ST. The primary end point was the change in peak walking time on a graded treadmill test at 6 months compared with baseline. Secondary end points included free-living step activity, quality of life with the Walking Impairment Questionnaire, Peripheral Artery Questionnaire, Medical Outcomes Study 12-Item Short Form, and cardiovascular risk factors. At the 6-month follow-up, change in peak walking time (the primary end point) was greatest for SE, intermediate for ST, and least with OMC (mean change versus baseline, 5.8±4.6, 3.7±4.9, and 1.2±2.6 minutes, respectively; P<0.001 for the comparison of SE versus OMC, P=0.02 for ST versus OMC, and P=0.04 for SE versus ST). Although disease-specific quality of life as assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire also improved with both SE and ST compared with OMC, for most scales, the extent of improvement was greater with ST than SE. Free-living step activity increased more with ST than with either SE or OMC alone (114±274 versus 73±139 versus −6±109 steps per hour), but these differences were not statistically significant. Conclusions— SE results in superior treadmill walking performance than ST, even for those with aortoiliac peripheral artery disease. The contrast between better walking performance for SE and better patient-reported quality of life for ST warrants further study. Clinical Trial Registration— URL: http://clinicaltrials.gov/ct/show/NCT00132743?order=1. Unique identifier: NCT00132743.

Peripheral Arterial Disease Is Associated With Higher Rates of Hip Bone Loss and Increased Fracture Risk in Older Men

Background— Peripheral arterial disease (PAD) and osteoporosis are chronic illnesses that increase in prevalence with aging and certain metabolic disorders. The association between PAD, rates of bone loss, and fracture risk in older men is uncertain. Methods and Results— We sought to test the hypothesis that PAD is associated with higher rates of bone loss and increased fracture risk. We analyzed data from a prospective cohort study involving 6 US centers and 5781 men at least 65 years of age. We assessed ankle-brachial index and hip bone mineral density, followed up prospectively for changes in hip bone mineral density and fractures. PAD was defined as a baseline ankle-brachial index <0.9. Hip bone mineral density was measured with dual x-ray absorptiometry at baseline and again an average of 4.6 years later. Incident nonspine fractures were ascertained by self-report and confirmed with radiography reports during an average of 5.4 years of follow-up. At baseline, the prevalence of PAD was 6.2%. After adjustment for age, race, site, and baseline bone mineral density, the mean annualized rate of bone loss at the total hip was −0.66% per year (95% confidence interval −0.78 to −0.54) in men with PAD compared with −0.34% per year (95% confidence interval −0.36 to −0.31) in men without PAD (P<0.001). After further adjustment for multiple potential confounders, the difference was attenuated (−0.49% in men with PAD versus −0.35% in men without PAD) but remained significant (P=0.02). Findings were similar at hip subregions. Twelve percent of men with PAD and 7.9% of those without PAD experienced an incident nonspine fracture (hazard ratio adjusted for age, race, and site=1.47, 95% confidence interval 1.07 to 2.04); this association was not altered substantially by further adjustment for multiple confounders. Conclusions— In community-dwelling older men, PAD was associated with higher rates of hip bone loss and increased risk of nonspine fractures. Further research should examine the biological mechanisms underlying the association between reduced limb blood flow and fractures.

Effects of a Home-Based Walking Intervention on Mobility and Quality of Life in People With Diabetes and Peripheral Arterial Disease: A randomized controlled trial

OBJECTIVE Determine the efficacy of a home-based walking intervention to improve walking ability and quality of life in people with diabetes and peripheral arterial disease (PAD). RESEARCH DESIGN AND METHODS We conducted a randomized, controlled, single-blind trial within university-affiliated clinics in our local community. We randomized 145 participants (45 women) with diabetes and PAD to our intervention—a 6-month behavioral intervention targeting levels of readiness to engage in routine walking for exercise—versus attention control. Our primary outcome was 6-month change in maximal treadmill walking distance. Secondary outcomes included 3-month change in maximal walking distance, lower limb function (i.e., walking impairment scores), quality of life (Medical Outcomes Short Form Survey), exercise behaviors, depressive symptoms, and self-efficacy at 3 and 6 months. RESULTS The mean age of participants was 66.5 (SD 10.1) years. Intervention and control groups did not differ significantly in 6-month change in maximal treadmill walking distance (average [SE] 24.5 [19.6] meters vs. 39.2 [19.6] meters; P = 0.60). Among secondary outcomes, for the intervention and control groups, respectively, average walking speed scores increased by 5.7 [2.2] units and decreased by 1.9 [2.8] units (P = 0.03); the mental health quality of life subscale score increased by 3.2 [1.5] and decreased by 2.4 [1.5] units (P = 0.01). CONCLUSIONS A home-based walking intervention did not improve walking distance but did improve walking speed and quality of life in people with diabetes and PAD. Clinicians should consider recommending home-based walking therapy for such patients.

Design of the multicenter standardized supervised exercise training intervention for the 'CLaudication: Exercise Vs Endoluminal Revascularization (CLEVER) study'

Abstract The CLaudication: Exercise Vs Endoluminal Revascularization (CLEVER) study is the first randomized, controlled, clinical, multicenter trial that is evaluating a supervised exercise program compared with revascularization procedures to treat claudication. In this report, the methods and dissemination techniques of the supervised exercise training intervention are described. A total of 217 participants are being recruited and randomized to one of three arms: (1) optimal medical care; (2) aortoiliac revascularization with stent; or (3) supervised exercise training. Of the enrolled patients, 84 will receive supervised exercise therapy. Supervised exercise will be administered according to a protocol designed by a central CLEVER exercise training committee based on validated methods previously used in single center randomized control trials. The protocol will be implemented at each site by an exercise committee member using training methods developed and standardized by the exercise training committee. The exercise training committee reviews progress and compliance with the protocol of each participant weekly. In conclusion, a multicenter approach to disseminate the supervised exercise training technique and to evaluate its efficacy, safety and cost-effectiveness for patients with claudication due to peripheral arterial disease (PAD) is being evaluated for the first time in CLEVER. The CLEVER study will further establish the role of supervised exercise training in the treatment of claudication resulting from PAD and provide standardized methods for use of supervised exercise training in future PAD clinical trials as well as in clinical practice.

The role of nutrition and body composition in peripheral arterial disease.

Peripheral arterial disease (PAD) has not been as extensively investigated as other cardiovascular diseases. However, the available data suggest that nutrition-based treatment strategies have the potential to reduce the cost-economic burden of PAD substantially. Abdominal obesity is associated with PAD and prospective and cross-sectional studies have shown that a low dietary intake of folate and reduced synthesis of vitamin D are associated with an increased risk of PAD and severe walking impairment in patients who have the disease. However, dietary patterns that are associated with decreased cardiovascular risk might protect against PAD. A small number of clinical trials have provided evidence that increased intakes of niacin and insoluble fiber might be associated with decreased levels of LDL cholesterol and thrombogenic biomarkers, as well as increased serum levels of HDL cholesterol in patients with PAD. However, little evidence that antioxidants, vitamins B6 and B12, or essential fatty acid supplements improve clinical outcomes in these patients exists. Overall, data on the effects of nutrition, body composition, and nutritional supplementation on the risk, progression, and prognosis of PAD are scarce. Further research into these areas is required to allow the development of evidence-based nutritional guidelines for the prevention and treatment of the disease.

Predictors of smoking reduction among Blacks

INTRODUCTION Blacks who smoke have increased tobacco-related health risks. Cessation decreases the likelihood of many health problems. Smoking reduction may be important in the cessation process and potentially reduce health risks. METHODS Because little is known about specific predictors of smoking reduction, we investigated factors predicting reduction among Black light smokers enrolled in a 26-week cessation trial. Specifically, we compared (a) reducers (reduced cigarettes per day [cpd] >or=50%) with nonreducers and (b) reducers with quitters. Baseline demographic, smoking-related, and psychosocial variables were collected, and Week 26 smoking status was assessed. RESULTS Among 539 participants, 41.0% (n = 221) reduced their smoking, 17.6% (n = 95) quit, and 41.4% (n = 223) did not reduce their smoking by >or=50%. In comparison with reducers, nonreducers were more likely to have their first cigarette within 30 min of waking (odds ratio [OR] = 2.4, 95% CI = 1.47-3.93), lower baseline cpd (OR = 0.84, 95% CI = 0.77-0.93), higher baseline cotinine levels (OR = 1.002, 95% CI = 1.000-1.003), lower perceived stress (OR = 0.86, 95% CI = 0.78-0.95), and higher Smoking Consequences Questionnaire (SCQ) negative social impression scores (OR = 1.04, 95% CI = 1.01-1.06), after controlling for treatment arm, gender, and age. Significant predictors of smoking cessation versus reduction included lower baseline cpd (OR = 0.85, 95% CI = 0.75-0.95), higher nicotine dependence (OR = 1.47, 95% CI = 1.09-1.98), lower baseline cotinine levels (OR = 0.996, 95% CI = 0.994-0.998), higher body mass index (OR = 1.05, 95% CI = 1.01-1.08), lower perceived stress (OR = 0.82, 95% CI = 0.72-0.95), and higher SCQ negative social impression scores (OR = 1.05, 95% CI = 1.01-1.08). DISCUSSION Distinct predictors are associated with different trajectories of smoking behavior change (i.e., reduction vs. cessation vs. no change).

Self-efficacy is associated with walking ability in persons with diabetes mellitus and peripheral arterial disease

Self-efficacy is a known predictor for behavior change. Little is known about the association of self-efficacy with walking ability in individuals with diabetes mellitus and peripheral arterial disease (PAD). The objective of this study was to determine the association of self-efficacy with walking ability in individuals with diabetes mellitus and PAD. In this cross-sectional study, baseline data were analyzed from individuals with diabetes mellitus type 1 or 2 and PAD who were enrolled in a walking intervention clinical trial. As part of the baseline assessment, individuals completed questionnaires to ascertain self-efficacy and co-existing illnesses. In addition, participants completed a treadmill walking test and a 6-minute walking test. A total of 145 individuals were enrolled (mean age 66.5 ± 10.1 years) with diabetes mellitus and PAD; 45 (31%) were women. The mean ankle—bracial index was 0.70 (range − 0.18—2.20) and the mean glycosylated hemoglobin value was 7.1 (SD 1.2). The mean distance walked, as per the treadmill walking test, was 418 meters (SD 258) and the mean distance walked, as per the 6-minute walking test, was 272 meters (SD 74). As measured by the treadmill walking test and the 6-minute walking test, self-efficacy was associated with treadmill walking distance, coefficient 33.0 (95% CI 11.0, 55.1; p = 0.0036), and the 6-minute walking test, coefficient 10.4 (95% CI 3.0, 17.7; p = 0.0061), after adjusting for comorbidities, social habits, and disease severity. In conclusion, self-efficacy, a psychosocial mediator for behavior change, was significantly associated with walking ability in individuals with diabetes mellitus and PAD. Future studies should determine the benefits of targeting self-efficacy to improve adherence to walking therapy in patients with PAD.

Unsupervised walking therapy and atherosclerotic risk-factor management for patients with peripheral arterial disease: A pilot trial

Background: Although only a small percentage of patients with peripheral arterial disease (PAD) have claudication, many more suffer from atypical leg symptoms.Purpose: This pilot trial evaluated a risk-factor modification program to improve walking ability in patients with PAD and leg symptoms other than intermittent claudication.Methods: Patients 18 years or older with an ankle-brachial index (ABI) of 0.50 to 0.89 completed a baseline assessment of current walking ability, physical activity level, health-related quality of life, glycosylated hemoglobin values, and fasting lipid profiles. Patients were randomized to usual care (control group) versus usual care plus an educational intervention on risk-factor management (intervention group). We compared functional outcomes between and within groups using the Student’s t test and control and intervention group outcomes at 12 weeks using analysis of covariance with the baseline value as the covariate.Results: We randomized 50 patients into two treatment arms. There was no difference in the mean age of patients in each group. At baseline, mean ABI for the control versus the intervention group was 0.72 (SD=0.10) and 0.75 (SD=0.10), respectively, and mean stair-climbing values did not differ between groups. At 12 weeks, mean stair-climbing values were 40.2 (SD=30.2) for the control and 61.2 (SD=32.8) for the intervention group. The difference in adjusted mean walking distance between groups at 12 weeks was not significant. Analysis of covariance associated assignment to the intervention versus the control arm with a significant increase at 12 weeks in the ABI (p=.008) and stair-climbing ability (p=.02).Conclusions: Patients in the intervention group improved objective measures of blood flow and reported stair-climbing ability.

Change in Smoking, Diet, and Walking for Exercise in Blacks

Positive changes in one health behavior may be accompanied by other constructive health behavior changes. Thus, the authors investigated the association of smoking reduction and cessation to changes in fruit and vegetable (FV) intake and engaging in walking for exercise. This study included 539 Black light smokers (≤10 cigarettes per day ≥25 days/month) enrolled in a 2 × 2 factorial study (placebo vs. nicotine gum, health education vs. motivational interviewing). Reducing cigarette consumption (p = .02) and quitting smoking (p < .01), as well as receiving the nicotine gum (p = .04), was associated with increased FV intake, after controlling for baseline FV intake. Compared with those who did not reduce their smoking, both reducers (p < .001) and quitters (p < .001) were more likely to walk for exercise at follow-up, after controlling for baseline walking status (p = .01). Thus, addressing one health risk behavior may prompt other positive health behaviors, which may argue for developing interventions targeting multiple health risk behaviors.

Mortality following operations for lower extremity peripheral arterial disease

Background We sought to identify risk factors associated with mortality following surgery for peripheral arterial disease (PAD). Methods We evaluated the association between levels of control of atherosclerotic risk factors and time to mortality following either lower extremity bypass surgery or lower extremity amputation using Cox proportional hazards regression. Results Among 796 patients with PAD (defined by an ankle-brachial index [ABI] < 0.9), 230 (28.9%) underwent an operation for PAD (136, lower-extremity bypasses; 111, lower-extremity amputations). Participants were followed for up to six years after their diagnosis of PAD. A total of 107 (46.5% of the 230) died during the period of follow-up. Factors associated with mortality following lower extremity bypass surgery included age 70 years and older hazard ratio [HR] 1.88; 95% confidence interval [CI]: 1.01–3.51) and of African American race (HR 1.94; 95% CI: 1.04–3.62). Renal insufficiency was significantly associated with mortality following lower extremity amputation (HR 2.19; 95% CI: 1.16–4.13). Conclusion Our data provide information on preoperative risk variables to consider when assessing long-term mortality in persons with PAD who are undergoing surgery for PAD.