The Effects of Diet and Exercise Interventions in Peripheral Artery Disease

PROJECT SUMMARY Objective. Our objective is to build on our preliminary work that demonstrates a modified dietary approaches to stop hypertension (modDASH) eating plan combined with a standard exercise program will be a better overall treatment for patients with peripheral artery disease (PAD) to improve walking, local microvascular function, and vascular inflammation. Specific Aims. We propose to test the efficacy of a modDASH dietary program combined with an exercise program (modDASH+Ex) to improve exercise and vascular outcome measures in patients with PAD and claudication beyond that of the standard treatment of an exercise program (Ex). Our central hypothesis is that the modDASH+Ex program improves the efficacy to rehabilitate PAD patients by improving exercise outcomes, health-related quality of life (HRQoL), local microvascular function, and vascular inflammation more than the standard Ex program. This clinically relevant hypothesis will be tested through the following aims: Aim 1 (Exercise Outcomes). To compare the changes in ambulation and HRQoL in PAD patients following the combined modDASH+Ex program, and following the Ex program which represents standard of care treatment. Aim 2 (Local and Systemic Vascular Outcomes). To compare the changes in local microvascular function of the lower extremities and inflammation in patients following the combined modDASH+Ex program, and following the Ex program. Aim 3. To explore the causal mechanism that changes in local microvascular function and vascular inflammation are physiologic mechanisms that precede changes in ambulation following the modDASH+Ex and Ex programs, and whether changes are more predictive following modDASH+Ex program. Methods. This is a 3-month, patient-oriented, translational, comparative effectiveness randomized controlled trial. A total of 184 patients will be randomized into either the modDASH+Ex program (N=92) or the Ex program (N=92). All patients will perform home-based walking for 3 months, and patients randomized to the modDASH+Ex program will progressively increase their daily servings of fruits and vegetables by up to 3-4 servings above baseline during the program. Clinical Significance. If successful, combining the modDASH eating plan with a home-based exercise program will be a novel and innovative behavioral paradigm to optimally improve peak walking time, HRQoL, local microvascular function and vascular inflammation in PAD patients. These improvements could impact the clinical course of PAD by reducing long-term risks of major adverse cardiovascular and lower extremity events.