The core diet. Whole grains, legumes, lentils, other vegetables, and fruit comprised the major portion of the diet. We reassured patients that balanced and varied plant-based nutrition would cover their needs for amino acids, and we encouraged them to take a multivitamin and vitamin B12 supplement. We also advised the use of flax seed meal, which served as an additional source of omega-6 and omega-3 essential fatty acids.
Foods prohibited. Initially the intervention avoided all added oils and processed foods that contain oils, fish, meat, fowl, dairy products, avocado, nuts, and excess salt. Patients were also asked to avoid sugary foods (sucrose, fructose, and drinks containing them, refined carbohydrates, fruit juices, syrups, and molasses). Subsequently, we also excluded caffeine and fructose.
Exercise was encouraged but not required. The plan also did not require the practice of meditation, relaxation, yoga, or other psychosocial support approaches. Patients continued to use cardiac medications as prescribed, monitored by their (other) physicians.
Pre-intervention training. Each participant attended a single-day 5-hour counseling seminar (9 am-2 pm) with, at most, 11 other participants. Each participant was encouraged to invite a spouse or partner. The 5-hour program profiled plant-based cultures that have virtually no cardiovascular illness, in contrast to non-plant-based cultures where CAD is ubiquitous (confirmed by autopsy of young adults).14 We referenced the plummeting death rates from strokes and heart attacks in Norway during World War II when the German occupying forces confiscated their livestock, limiting Norwegians to plant-based nutrition.15
We emphasized the cellular components and mechanisms responsible for vascular health: the endothelial cell, endothelial progenitor cell, high-density lipoprotein cholesterol (HDL-C), and inhibition of dimethylarginine dimethylaminohydrolase that causes vasoconstriction. These were discussed in considerable detail, as were nutrition strategies to enhance endothelial health and to avoid endothelial dysfunction and injury. Participants viewed angiograms of CAD reversal from prior intervention participants.
An associate with several decades of experience with plant-based nutrition discussed plant food acquisition (including food label reading) and preparation. Participants learned how to alter common recipes to meet program standards. They received a 44-page plant-based recipe handout, 2 scientific articles confirming plant-based nutrition effectiveness,4,16 and, after 2007, a copy of Prevent and Reverse Heart Disease.2 The seminar concluded with a testimonial by a prior participant, a plant-based meal, and a question-and-answer session. We asked participants to complete and return a 3-week diet diary following the seminar. They were invited to communicate concerns via e-mail or phone, and to forward copies of subsequent lipid profiles, stress tests, cardiac events, angiograms, and interventions.
Study data acquisition
In 2011 and 2012 we contacted all participants by telephone to gather data. If a participant had died, we obtained follow-up medical and dietary information from the spouse, sibling, offspring, or responsible representative. Patients who avoided all meat, fish, dairy, and, knowingly, any added oils throughout the program were considered adherent. We inquired about weight change, lipid profiles, further stress tests or angiograms, major cardiac events, interventions, and any change in symptoms.
RESULTS
Characteristics of participants
Baseline characteristics of participants are shown in TABLE 1. (Two patients from the original group of 200 were lost to follow-up.) The remaining 198 participants for whom data were available had CVD, were mostly men (91%), averaged 62.9 years of age, and were followed for an average of 44.2 months (3.7 years).
Three patients had noncoronary vascular disease: 1 cerebral vascular disease, 1 carotid artery disease, and 1 peripheral arterial disease. In the remaining 195 patients, angiogram results confirmed the diagnosis of CAD in 180 (92%). With the other 15 participants, electrocardiography, failed stress tests, or a history of enzyme-documented MI confirmed the diagnosis of CAD. Of the 195-patient cohort, 44 (23%) had an MI prior to counseling.
Outcomes for nonadherent CVD participants
Twenty-one patients (11%) were nonadherent with dietary intervention. Thirteen of these patients experienced at least 1 adverse event each—2 sudden cardiac deaths, 1 heart transplant, 2 ischemic strokes, 4 PCIs with stent placement, 3 coronary artery bypass graftings (CABGs), and 1 endarterectomy for peripheral arterial disease—for a patient event rate of 62% (TABLE 2).
Outcomes of adherent CVD participants
In the group of 177 (89%) adherent patients, 112 reported angina at baseline and 104 (93%) experienced improvement or resolution of symptoms during the follow-up period. An additional patient with claudication also experienced symptom relief (TABLE 2). Of adherent patients with CAD, radiographic or stress testing results were available to document disease reversal in 39 (22%). Twenty-seven CAD participants were able to avoid PCI or CABG that was previously recommended. Adherent patients experienced worse outcomes significantly less frequently than nonadherent patients (P<.001, Fisher’s exact test). In addition, for 135 patients for whom body weight was available, the average weight loss was 18.7 lbs.