ABSTRACT
Background: Cardiac Rehabilitation (CR) is a supervised exercise and risk factor modification program for patients with cardiac conditions. Endothelial dysfunction is often present and is associated with worsening cardiac prognosis, and several studies have indicated that standard onsite CR has improved endothelial function in heart disease patients. However, during the COVID-19 pandemic, many CR programs transitioned to a virtual or hybrid model of care to increase safety of CR programs. Objective(s): The objective of this study was to determine vascular function of patients with coronary artery disease (CAD) measured before and after 4 months of outpatient CR using a virtual model of care. Method(s): Virtual CR included 1 virtual group session/week by videoconferencing and hybrid CR included 1 session/week (4 on-site and 12 virtual group sessions) for a total of 16 weeks. CAD patients (6 females, 4 males) mean age 68.1+/-7.5 years rested in a supine position to measure 1) brachial artery flow-mediated dilation (FMD), 2) microvascular function, and 3) augmentation index (AI) using ultrasound sonography (n=8) and an EndoPAT 2000 (n=9). Two patients completed virtual CR and the rest underwent hybrid CR. These measurements were obtained concurrently using an ultrasound transducer at the brachial artery proximal to a blood pressure cuff on the forearm with EndoPAT cuffs on the index fingers during 5-minute intervals of baseline, occlusion, and recovery. FMD results were analyzed using automated Cardiovascular Suite software. AI and Reactive Hyperemia Index (LnRHI) were determined using automatic analysis via the EndoPAT 2000. Anthropometrics, blood pressure, and food intake were recorded at each visit. Patients were advised to refrain from strenuous exercise, alcohol, caffeine, and highly saturated foods at least 12 hours prior to the study appointment. One tailed paired t-tests were conducted between baseline and completion. Result(s): Adherence to CR averaged 10.3+/-3.2 out of 16 sessions. FMD improved from (2.75+/-1.71% to 5.63+/-4.37%, p=0.048) while there was no improvement in AI (14.2+/-18.8 to 13.2+/-19.6, p=0.45) or LnRHI (0.56+/-0.12 to 0.52+/-0.20, p=0.24). Conclusion(s): While there was no improvement in LnRHI or AI after CR, FMD improved in CAD patients after 4 months of adapted CR. Our results indicate that while virtual and hybrid models of CR may not be sufficient for improving microvascular function and aortic stiffness in CAD, there is an improvement of endothelial function. Future studies should examine the effects of adherence, duration and exercise intensity within these alternative models of CR on aortic and microvascular improvements.
ABSTRACT
BACKGROUND: Healthy diet and exercise are associated with reduced risk of dementia in older adults. The impact of diet and exercise interventions on brain health is less consistent, especially with dietary interventions which rely on varying approaches. Our objective was to evaluate the feasibility and preliminary efficacy of a 6-month intervention combining exercise with a novel dietary counseling approach to improve hippocampal volume among older adults at-risk for dementia. METHODS: Participants with vascular risk factors and subjective cognitive decline or early mild cognitive impairment were cluster randomized in groups of 3-4 to the diet intervention (DIET) or control education (ED) group. All participants engaged in 1 h of supervised exercise per week and additional exercise at home. DIET involved 1 h per week of group-based dietary counseling comprising education, goal setting, and strategy training. ED involved 1 h per week of group-based brain health education classes. Our primary outcome was change in hippocampal volume from baseline to 6 months. Secondary outcomes included changes in cognitive function, blood biomarkers, diet, and fitness. Recruitment challenges and early discontinuation of the trial due to COVID-19 necessitated a revised focus on feasibility and preliminary efficacy. RESULTS: Of 190 older adults contacted, 14 (7%) were eligible and enrolled, constituting 21% of our recruitment target. All participants completed the intervention and attended 90% of exercise and DIET/ED sessions on average. All 6-month assessments prior to COVID-19 were completed but disruptions to in-person testing resulted in incomplete data collection. No serious adverse events occurred and all participants expressed positive feedback about the study. Preliminary findings did not identify any significant changes in hippocampal volume; however, substantial improvements in diet and HbA1c were observed with DIET compared to ED (d = 1.75 and 1.07, respectively). CONCLUSIONS: High adherence and retention rates were observed among participants and preliminary findings illustrate improvements in diet quality and HbA1c. These results indicate that a larger trial is feasible if difficulties surrounding recruitment can be mitigated. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03056508 .