Medical College of Wisconsin

Coronary Artery Disease (CAD) remains a leading cause of morbidity and mortality worldwide despite improved mitigation of traditional risk factors. Large association studies have linked the gut microbiome alterations with inflammation, CAD, and traditional CAD risk factors. Subsequent studies have shown concomitant improvements in gut dysbiosis, inflammation, and cardiometabolic diseases using probiotics and other gut-modulating therapies. To date, many studies have shown a correlative relationship between intestinal bacteria composition and the presence of CAD, or severity of heart attacks, but few have begun to elucidate potential metabolic and immunologic mechanisms.
The investigator's recently supplemented Lactobacillus plantarum 299v in men with stable CAD, which improved systemic inflammation and brachial artery flow-mediated dilation (BA-FMD) - a measure of endothelial function and a predictive CAD precursor. Improvement in BA-FMD positively correlated with increased serum propionic acid (PA) concentrations. PA is a gut microbiome-derived short chain fatty acid (SCFA) with known human vascular receptors and implicated in endothelial function, innate immunity, and glucose homeostasis.
Whether PA is mediating improvement in endothelial dysfunction or inflammation in the investigator's prior experiment remains unknown. The investigator's objective is to determine whether endothelial cell function is improved by dietary supplementation of sodium propionate in patients with established coronary artery disease. Furthermore, the investigators wish to elucidate to what extent inflammation is reduced by this therapy, by both measuring serum inflammatory markers and by seeing if plasma from treated patients induces anti-inflammatory transcriptomic responses from cultured endothelial cells and peripheral blood mononuclear cells, both of which are involved in atherosclerosis.
Specific Aim 1 will determine the impact of dietary PA supplementation on endothelial function and traditional CAD risk factors in patients with CAD. The investigators will utilize ultrasound to assess the percent change in BA-FMD before and after dietary PA supplementation. The extent of endothelium-dependency of these responses will be tested by measuring BA-FMD following nitroglycerin administration. The investigators will also measure markers representative of traditional CAD risk factors, such as lipid levels and HgbA1C.
Specific Aim 2 will determine anti-inflammatory changes in vivo and in transcriptomic signatures of cultured EC and PBMCs induced by dietary PA. The investigators will measure changes to systemic serum inflammatory markers involved in atherosclerotic processes using a targeted metabolomics approach, using plasma from the investigator's cohort before and after PA supplementation. Plasma samples will be used to incubate aforementioned cells to compare transcriptomic signatures of cells subjected to pre-supplementation plasma versus post-supplementation plasma. The investigators will use Ingenuity Pathway Analysis to determine changes to inflammatory pathways and i.i.com to determine whether more anti-inflammatory signatures were induced.
Specific Aim 3 will determine the impact of PA supplementation on gut microbiome taxonomy and diversity. As an optional additional clinical study activity, the investigators will collect stool samples before and after dietary PA supplementation, subject samples to multiplex 16S RNA sequencing, and calculate the Shannon Diversity Index. This will help us determine changes in individual gut microbiome constituents and diversity of the entire population.

Cardiometabolic diseases are major causes of morbidity and mortality in the state of Wisconsin and are expected to pose an increasing burden over the next few decades. A crucial initial step in preventing or delaying the onset of these diseases is to assess disease risk at the individual level. However, the accuracy of risk prediction of disease events based on conventional risk factors remains modest. Incorporating a polygenic risk score (PRS) into risk equations improves risk prediction but there is uncertainty about how best to integrate PRSs into primary care settings, given the lack of familiarity with PRSs among patients and providers. Probabilistic estimates for risks of cardiometabolic diseases may be misunderstood, and genetic risk assessment may not be trusted by those in low resource rural or inner-city settings. The potential for using PRSs to refine disease risk estimates has led to numerous studies to assess their clinical utility; however, the vast majority have been conducted in tertiary academic medical centers, raising concern that communities with diminished access to care could be left behind. The study team will investigate how the use of PRSs for such diseases influences health outcomes in rural and inner-city settings. The study team will leverage prior experience in conducting the MIGENES randomized clinical trial (RCT) of disclosing polygenic risk of CHD in a preventive cardiology setting of an academic center. In the proposed study, the investigators will conduct a pragmatic RCT to extend the investigation to 'real-world' settings of primary care clinics in a rural medical center and an urban Federally Qualified Health Center (FQHC). The investigators will engage a Community Advisory Board (CAB) through focus groups to gather feedback on implementing PRS-guided screening, related medical and lifestyle interventions, and public health strategies to reduce CHD risk. Feedback will inform provider education, targeted outreach to Wisconsin residents, and identification of barriers to adoption. The study team will also assess primary care physicians' and patients' familiarity with polygenic risk, their attitudes toward PRS testing, and intended actions based on results, comparing responses across rural and urban settings. The 10-yr risk of CHD will be estimated based on pooled cohort equations (PCE). Participants will view a video describing how cardiovascular risk was estimated and how lifestyle changes and drug therapy could reduce such risk and, in those randomized to receive PRS, the probabilistic nature of genetic risk. Patients will then see their PCP to review the 10-yr CHD risk estimate and engage in shared decision-making regarding statin therapy. Patient and clinician understanding of polygenic risk information will be assessed, as well as health-related and behavioral outcomes.

This is a single-center, double-arm, open-label, randomized feasibility study that will determine whether a novel clinical decision aid accessed via the electronic health record will be acceptable to both cancer survivors and their cardiologists, will favorably impact appropriate medication use and cardiac imaging surveillance, and will improve clinician and patient decision-making, perception, and behavior towards cardioprotective medication usage and cardiovascular disease imaging utilization.