Among the 177 patients who reported adherence to the dietary intervention, there were 5 noncardiac deaths (3 cancers, 1 pulmonary embolus, and 1 case of pneumonia). Also, 9 CAD patients required vascular intervention: 1 CABG for disease progression, 1 CABG for malpositioned dissecting stents placed just prior to enrollment into the program, 1 stenting procedure and 2 CABGs before valve repair, 2 stenting procedures to correct grafted artery closing, and 2 CABGs for asymptomatic patients persuaded of the need by their primary caregivers. Two patients experienced a nonfatal stroke (one after refusing warfarin for atrial fibrillation, the second because of progression of CVD, and one had stent thrombosis with acute MI after discontinuing clopidogrel as advised by the primary care physician. One patient had 3 stents placed before entering our study; 1 occluded at 3 years into the study, necessitating restenting (TABLE 2).
Thus, only 1 major cardiovascular event (stroke) was related to disease progression in patients adherent with the dietary intervention. This is a recurrent event rate of 0.6%. Thus, 99.4% of adherent patients avoided major cardiac events. This result clearly contrasts with that of other key peer-reviewed studies of nutrition interventions for patients with CAD6,17-22 (TABLE W3), although the disease burden and the presence of comorbid conditions may not be comparable. Even if all events had been attributable to diet, the 10% (18/177) event rate (“Worse” group in TABLE 2) over an average of 3.7 years is much below that reported in the literature23 and the 62% of the nonadherent group.
DISCUSSION
This program of treating the presumed cause of CAD has yielded significant findings and raised practice implications. First, and quite compelling, is that 89% of patients were willing to make a substantial lifestyle transition to plant-based nutrition and sustain it for an average of 3.7 years (for some patients up to 13 years). Most participants saw this as taking control of their disease (anecdotal reports).
Second, the results of this evaluation provide further evidence that plant-based nutrition may prevent, halt, and reverse CAD. This process of halting and reversing CAD has been validated with a high probability by epidemiologic studies, including those of wartime deprivation, our previous noncontrolled study, and both randomized and nonrandomized controlled studies where a similar plant-based diet was a part of a comprehensive lifestyle modification in conjunction with otherwise standard pharmaceutical medical therapy.3,15,17,18,24-26
Large cohort studies support nutritional intervention. In addition, 2 large prospective cohort studies have recently emphasized the importance of nutrition in decreasing the risk of recurrent CVD events in people with CVD or diabetes and decreasing the risk of developing CVD among healthy individuals. Dehghan and colleagues27 followed 31,546 participants with CVD or diabetes over 4.5 years and divided them into quintiles of nutritional quality. Reduction in CVD-related risk within the healthiest quintile was 35% for death, 14% for MI, and 19% for stroke. They found this protective association was maintained whether or not patients were receiving medications.
Crowe and colleagues28 followed 44,561 men and women enrolled in the European Prospective Investigation into Cancer and Nutrition. Thirty-four percent (15,151) were vegetarians, consuming neither meat nor fish. During an 11.6-year follow-up, they found vegetarians had a lower mean body mass index, lower non-HDL-C level, lower systolic blood pressure, and a 32% lower risk of developing ischemic heart disease.28 These combined studies of 76,107 individuals support an assertion of the power of nutrition for primary and secondary prevention of cardiovascular illness.
By way of contrast are findings associated with a typical western diet. Wilkins and colleagues29 assessed lifetime risk and years lived free of total CVD by reviewing data from 905,115 person-years from 1964 to 2008. They assessed risk factor presence and subsequent CVD. While lifetime risk estimates for total CVD for all individuals was >30%, the study found that even those men and women 55 years of age with optimal risk factors had a 40% and 30% likelihood of total CVD, respectively, by age 85. It would appear that even optimal risk factors are no guarantee that the typical western diet won’t eventually result in CVD.
Why are our results particularly favorable? While nutritional modification is beneficial, the question remains whether it has been optimized to its fullest potential in other studies. First, no other nutrition study has completely eliminated oils (including food products that may contain even small quantities of added oil of any kind), and all animal, fish, and dairy products, which would avoid foods known to injure endothelial cells, as well as exogenous cholesterol and saturated fat. In avoiding exposure to lecithin and carnitine contained in eggs, milk and dairy products, liver, red meat, poultry, shellfish and fish, participants in our study were unlikely to have intestinal flora capable of producing trimethylamine oxide (TMAO), a recently identified atherogenic compound produced by the intestinal flora unique to omnivores that ingest animal products.30-32 (Vegans do not possess the detrimental bacterial flora.)