VANCOUVER, B.C. — Emerging data all point in the same direction: The intensive lifestyle modification program developed by Dean Ornish, M.D., reduces cardiovascular risk, including that of patients with diabetes.
The Ornish program—consisting of a low-fat vegetarian diet, stress management, moderate exercise, smoking cessation, psychological group support, and encouragement of partner participation—has been shown to bring about regression of even severe coronary atherosclerosis (Lancet 1990;336:129-33).
Since 1998, the Ornish program has been studied in the ongoing Multisite Cardiac Lifestyle Intervention Program (MCLIP), which now includes more than 1,600 participants in more than 22 U.S. sites.
An earlier demonstration project involving 440 subjects in eight U.S. sites showed that women benefit as much as men (Am. J. Cardiol. 2003;91:1316-22); data from 250 of those subjects showed that the program works just as well in places like West Virginia and Nebraska as it does in California. Dr. Ornish presented the findings at the annual meeting of the American Heart Association (FAMILY PRACTICE NEWS, Jan. 1, 2004, p. 20).
Now, new MCLIP findings by three of Dr. Ornish's associates at the Preventive Medicine Research Institute (PMRI), Sausalito, Calif., suggest that the regimen—officially called The Dr. Dean Ornish Program for Reversing Heart Disease—works in diabetic patients with coronary heart disease, and that each of the program's individual components appears to play a significant role in overall benefit. The data were presented in posters at the annual meeting of the American Psychosomatic Society.
Adherence Helps Diabetic Patients
Michael D. Sumner, Ph.D., was the lead author of the diabetes study, which included 461 patients, of whom 10% had type 1 diabetes, 48% had diagnosed coronary heart disease (the rest had other risk factors), and 56% were female.
The patients achieved good adherence to the intervention: a plant-based diet with just 10% of calories from fat, at least 3 hours of moderate exercise per week, 7 hours per week of yoga and other stress-management techniques, and twice-weekly professionally supervised group support sessions. Mean dietary fat levels dropped from almost 30% of total calories to just 10%, weekly exercise levels increased from 1.3 to 3.8 hours, and weekly stress management practices rose from 0.4 to 6.3 hours. Mean support group attendance was 94%.
After 12 weeks, the group lost an average of 5.6 kg, and dropped from an average body mass index of 35.6 kg/m
The drop in triglycerides was significant only in the men, but the changes in all other variables were significant for both genders, Dr. Sumner and his associates noted.
Diabetes-related changes included a drop in hemoglobin A1c from a mean of 7.5% to 6.7% and fasting glucose levels from 159 to 126 mg/dL, with similar results for both type 1 and type 2 diabetic patients. More than a third (39%) were able to reduce their use of diabetic medications. Quality of life measures, such as physical function, bodily pain, general health, vitality, and social functioning, also improved significantly, along with significant declines in measures of depression, hostility, and perceived stress.
Analyzing the Interventions
A second study, led by Jennifer Daubenmier, Ph.D., sought to determine the relative contributions of the program's individual behavior changes to reductions in coronary risk among 1,245 participants who had coronary heart disease (55%), diabetes, and/or at least three other risk factors (hypertension, hyperlipidemia, and obesity).
Changes at 12 weeks included significant reductions in weight (92.4 to 87.2 kg), functional capacity (9.0 to 10.9 metabolic equivalents), systolic blood pressure (133 to 123 mm Hg), diastolic blood pressure (79 to 73 mm Hg), total cholesterol (189 to 165 mg/dL), LDL cholesterol (108 to 92 mg/dL), and triglycerides (187 to 173 mg/dL). The group also had fewer depressive symptoms, lower hostility scores, and lower perceived stress after 12 weeks on the Ornish plan.
Regression analysis revealed significant additive effects of the health behaviors on decreases in weight, perceived stress, and depression at 12 weeks. For example, participants lost about 1.7% of body weight (1.53 kg) by reducing dietary fat, 1.2% (1.1 kg) through stress management practices, and 0.2% (0.18 kg) by exercising. (Remaining weight loss may have been due to other factors such as reduction in calories from sugar and alcohol.)
Reductions in dietary fat, exercise, and stress management also contributed significantly to levels of perceived stress, while improved diet and stress management contributed to lower depression scores.
The stress management component might indirectly boost the effects of diet and exercise in several ways. Yoga and meditation, for example, may facilitate healthier eating habits by increasing responsiveness to bodily cues and reducing stress-induced eating. Those practices might also mitigate cortisol-induced insulin resistance and weight gain.