Browsing by Subject "Peripheral artery disease"

Now showing 1 - 5 of 5
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    Body composition, nutrient intake and MTHFR genotype in patients with peripheral arterial disease
    (2014-05) Brostow, Diana P.
    Background: Peripheral artery disease (PAD) is a progressive disease characterized by its impact on physical mobility, and a high rate of vascular comorbidities and events. Despite its inclusion in the same grouping of conditions as cardiovascular (CVD) and cerebrovascular diseases, PAD garners much less attention, both in a clinical setting and in research. There is a significant body of research on the roles of nutrition and lifestyle in CVD and stroke etiology, yet the equivalent data for PAD is sparse. The impact of nutrition and related factors on PAD is poorly understood, and in need of expansive clarification.Methods: We conducted a literature review of all available research on nutrition and body composition in PAD, and used our assessments to design a cross-sectional study of these variables in a sample of PAD patients. We created a conceptual model of how nutrition-related variables may be associated with various aspects of PAD severity, and examined these associations within recruited participants.Results: Participants diets' were characterized by relatively high intakes of fat, sugar and sodium, as well as by low or inadequate intakes of crucial micronutrients. Several dietary factors were found to be significantly associated with more severe physical or psychosocial PAD symptoms. The majority of participants were also overweight or obese, and total body weight and abdominal obesity were associated with worse scores on tests of PAD severity. Additionally, we encountered several key obstacles to identifying and recruiting patients for this study. Conclusions: Although our sample size was relatively small, there is evidence to suggest that there are nutrition-related factors that are associated with the severity of PAD patients' symptoms and overall quality of life. Recruitment methods are in need of revision to obtain larger, more statistically powered samples, and we have outlined potential approaches for doing so. Lastly, this study establishes a precedent for future studies to implement interventions in PAD patients using already-established vascular guidelines for nutrition.
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    Characterization of the peripheral artery disease symptom experience
    (2013-08) Schorr, Erica Nicole
    Background: Claudication is the most commonly recognized symptom of PAD. It is classically described as an aching, cramping, painful, or tired feeling in the buttock or leg muscles. However, classic claudication is only reported in 7.5% to 33% of patients with PAD. Symptoms beyond classic claudication have been reported and suspected as being part of the symptom experience, but have not been validated as directly relating to changes in calf tissue oxygenation during exercise and subsequent recovery. Objective: The purpose of this study was to characterize the symptom experience of individuals diagnosed with PAD. Specific aims were to: (a) understand the symptom experience of individuals with PAD through in-depth qualitative interviews, and (b) simultaneously evaluate calf tissue oxygenation and self-reported symptoms experienced during treadmill exercise and throughout recovery. Method: Adults experiencing lower extremity symptoms during exercise due to underlying PAD were asked to participate. They were asked to: (a) complete a semi-structured interview to report their symptoms and describe their symptom experience in detail; (b) use a numeric rating scale (NRS) (0 to 5) to rate their symptoms during exercise and recovery; (c) provide descriptions of their symptom(s) during exercise and recovery; and (d) wear a near-infrared spectroscopy device to obtain information on tissue oxygenation during the exercise and recovery phases. Data were analyzed using content analysis, exploration of individual graphical trajectories, grouping trajectories, and multilevel modeling to examine the relationship between self-reported symptoms and calf tissue oxygenation. Results: A total of 40 participants were enrolled in this study. Participants were predominately Caucasian males. The average age of participants was 67.55 years (SD 9.18). Six themes emerged from 27 participant interviews: symptom descriptors, maintaining equilibrium, temporal fluctuations, the role of exercise, the perceived impact on QOL, and disease presence and treatment. During interviews, participants provided 24 symptom descriptors in 10 lower extremity locations. During treadmill exercise, participants provided 22 symptom descriptors in eight lower extremity locations. Under static and dynamic conditions, classic and `atypical' descriptors were used to describe discomfort in typical and `atypical' lower extremity locations. During three successive bouts of treadmill exercise, the largest drop in calf tissue oxygenation occurred between the start of exercise and the onset of symptom(s). During recovery, calf tissue re-saturation occurred steadily between maximum discomfort (i.e., a rating of 5 out of 5) and full symptom recovery. Individual changes in tissue oxygenation were related to total exercise time, baseline calf tissue oxygenation, exercise and recovery ratings, disease severity, and body-mass index. Conclusions: This study provides a preliminary understanding of the relationship between subjective symptom reporting and calf tissue oxygenation with a variety of PAD risk factors and individual characteristics. Continued research is necessary to validate `atypical' participant symptom reporting and broaden the currently accepted PAD symptom locations and descriptors. Despite the under-reporting of `atypical' symptoms compared to classic claudication, they do exist and they are no less important for the early detection, diagnosis, and treatment of PAD to minimize the impact of this painful, debilitating, and deadly disease.
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    The effects of two modes of exercise training on plasma biomarkers of inflammation and oxidative stress in patients with symptomatic peripheral artery disease
    (2014-08) Salisbury, Dereck Lee
    Introduction: Peripheral Artery Disease (PAD) is a manifestation of progressive atherosclerosis involving the main conduit arteries supplying the lower extremities. It is well known that atherosclerotic cardiovascular disease including PAD, is related partly to vascular inflammation and oxidative stress. Treadmill walking exercise to moderate claudication pain is considered the gold standard for improving walking distance in patients with PAD and claudication. Our group had previously reported that non-ischemia inducing upper body ergometry exercise training improves pain-free and maximal walking distance similar to ischemic inducing treadmill exercise training in patients with claudication. The influence of ischemic and non-ischemic inducing exercise training on systemic inflammation and vascular oxidative stress remains to be fully elucidated. Methods: A total of 75 patients (59 male and 16 female) with symptomatic PAD from the randomized controlled trial, Exercise Training to Reduce Claudication (EXERT), were used in a secondary analysis of inflammation and oxidative stress. Analysis of plasma for TNF alpha, IL-10, and F2 Isoprostane were performed at baseline and following 12 weeks of moderate intensity, claudication inducing treadmill training (T), upper body ergometry training (UBE), or usual care (C). Analysis of covariance was used to evaluate changes among groups for all biomarkers following intervention, using baseline level as a covariate. Pearson's correlation coefficient was used to assess correlation among baseline plasma biomarkers and physical and physiological variables. Results: After 12 weeks of intervention, all patients, regardless of the group increased TNF alpha levels. In particular, patients randomized to the UBE group significantly increased TNF alpha levels compared to the control group after adjusting for baseline TNF alpha and allopurinol (a significant covariate). Participants in the treadmill group had non-significant increases in IL-10, while all groups showed non-significant decreases in F2 Isoprostanes. Additionally there was no significant correlation between baseline plasma inflammatory and oxidative stress biomarkers, with physical and physiological variables such as ankle-brachial index, pain-free walking distance, and maximal walking distance at baseline. However, body mass index was significantly correlated to baseline TNF alpha levels (r=0.228, p=0.05). Conclusion: Moderate intensity UBE training appears to significantly increase the proinflammatory cytokine TNF alpha compared to a control group in patients with symptomatic PAD. However, all groups increased TNF alpha after 12 weeks of intervention, which contradicts the deemed anti-inflammatory effect of aerobic exercise training. It is clear that further study is required to establish if exercise training in patients with claudication is anti-inflammatory.
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    Peripheral Artery Disease: The Silent Killer
    (2012-07-26) Handley, Nathan
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    Understanding Lower Extremity Symptoms for Improved Detection of Peripheral Artery Disease: The PREDICT PAD Study
    (2021-08) Brown, Rebecca
    Background Of all the major manifestations of atherosclerosis, peripheral artery disease (PAD) is one of the most underdiagnosed and undertreated vascular diseases, due, in part, to the large number of individuals who experience atypical symptoms, yet our current screening tools are designed to detect those with classic symptoms. PAD causes functional decline and disability, low quality of life, and increased risk of all-cause mortality and cardiovascular death, therefore there is an immediate need to improve detection methods. Aims This dissertation is aimed to 1) Comprehensively describe the range of atypical symptom characteristics in individuals with PAD, how atypical symptoms are defined, and examine potential factors associated with atypical symptoms reported in the literature. 2) Identify characteristics that discriminate between PAD and non-PAD in a group of previously undiagnosed individuals with any type of lower extremity symptoms. 3) Measure the effects of exercise on symptom reporting and calf muscle ischemia and 4) elucidate the experience of individuals with undiagnosed PAD and explore differences in symptomatology in those with and without PAD. Methods Aim 1. A critical review of the published literature on symptom description in PAD was conducted with a particular focus on articles delineating classic or typical symptoms from atypical symptoms. Studies were analyzed based on methodological approach including a) questionnaire-based, b) clinician assessment, and c) qualitative interview. The definitions and associated conditions are discussed. Aim 2. One-time study visit was conducted to evaluate lower extremity symptoms at rest, during, and post exercise in adults 60 years and older with persistent lower extremity symptoms, not previously diagnosed with PAD (n = 25). Symptom assessment included validated questionnaires, a symptom adjective checklist, measurement of muscle tissue oxygenation, and an exploratory semi-structured interview. The visit concluded with a diagnostic vascular assessment using the ankle brachial index (ABI) test. Results were analyzed by naturally occurring groups based off the ABI (abnormal vs normal ABI). Aim 3. Symptoms were measured pre and post six-minute walk test to determine whether exercise elicits symptoms that more closely resemble classic PAD symptoms. Muscle tissue oxygen saturation was measured using near infrared spectroscopy to determine differences in recovery time post exercise between the PAD and non-PAD group. Aim 4. A qualitative content analysis of the audio-recorded semi-structured interviews was conducted to gain a deeper understanding of the differences between those with and without PAD and to understand the experience of individuals with undiagnosed PAD. Results Aim 1. Twenty-four articles were included in the review and was comprised of 8,169 unique individuals with PAD, with an average age of 68.0 years (42.3% female). The definition of atypical symptoms varied across the literature, as did the prevalence ranging from 7.9% - 50.3%. Atypical symptoms were more often associated with increased rates of comorbid diseases, coexisting conditions affecting ambulation, and a greater number of PAD risk factors. The majority of participants reported atypical symptoms and as well as interference with activities of daily living, physical function, and social and personal lives. Aim 2. Four questions were statistically significantly different between participants in the PAD group vs. the non-PAD group. Two of the four questions are contrary to the expected findings. The questions that best differentiated PAD from non-PAD were “Do your symptoms disappear while walking?”, “Do you have difficulty keeping up with your friends or family?”, “Do you have symptoms while sitting?”, “Where are your symptoms?”. Participants in the PAD group reported that their symptoms did not disappear while walking, they had difficulty keeping up with friends and family, had pain while sitting, and were less likely to experience calf or thigh pain. Aim 3. Exercise did not yield symptoms that more closely resembled classic PAD symptoms. Post exercise, the sensitivity and specificity of the validated screening questionnaires were either unchanged or worse. Participants in the PAD group took longer to recover based off return to normal muscle tissue oxygenation levels. Aim 4. The content analysis revealed eight concepts, two of which were unique to the PAD group. These were: Breath of Physical Findings and Confounding Factors, Coping Strategies, Impact on Activities of Daily Living, Determinants of Behavior, Communication Barriers, Symptoms Threaten, Credibility Feels at Risk (PAD only), and Unexplained Symptoms are Distressing (PAD only). Conclusion This dissertation examined discriminating characteristics of PAD in a sample of participants who were previously undiagnosed. Four screening questions may improve detection of PAD, however there are many communication barriers, atypical symptoms, and overlapping symptoms which continuously plague this approach to screening. Participants with undiagnosed PAD experienced discomfort, social limitations, and were distressed over their symptoms. The results emphasize the need to use definitions that serve to meet the needs of the patients who experience them. A broader definition of claudication beyond classic claudication is needed to improve access to vascular testing and enhance detection of PAD.