A long-term nutrition intervention experience: lipid responses and dietary adherence patterns in the Multiple Risk Factor Intervention Trial.

Nutrition counselors in the Multiple Risk Factor Intervention Trial (MRFIT) were able to help middle-aged men who were at high risk for coronary heart disease change their dietary habits, maintain those changes over time, and decrease their serum cholesterol levels. Most of a 7.5% mean serum cholesterol reduction achieved after 6 years of nutrition intervention occurred during the first year of the trial and was thereafter sustained. Total cholesterol and low-density lipoprotein cholesterol fraction decreases indicated improvement in terms of coronary heart disease risk. The food record rating, a numerical, semi-objective adherence technique that assesses a 3-day food record with respect to lipid-lowering potential, was used throughout the trial to measure adherence to recommended food patterns. Participants with lower food record rating scores, which indicate better adherence, demonstrated greater reductions in serum total cholesterol, plasma total cholesterol, and low-density lipoprotein fraction cholesterol determinations on a group basis. Subjective evaluations of the suitability of home and working environments, evidence of deviation from the MRFIT food patterns, and overall nutrition program motivation also showed that as ratings in each category became more favorable, lower food record rating scores and greater blood lipid reductions were consistently observed. The subgroup of participants who were non-smokers and not hypertensive demonstrated greater lipid responses and better dietary adherence. Continued smoking and antihypertensive medications appeared to adversely influence dietary adherence and/or lipid reductions. The MRFIT experience, however, demonstrated for the first time that dietary changes and blood lipid reductions can be achieved after the initial intervention effect, despite a continued emphasis on high blood pressure management and smoking cessation.

Nutrition in the Multiple Risk Factor Intervention Trial (MRFIT).

The Multiple Risk Factor Intervention Trial (MRFIT) is a clinical trial to determine whether primary prevention of coronary heart disease (CHD) is achievable. The main objective is to learn whether a special intervention program for men at increased risk of death from CHD can result in a significant reduction in mortality from this disease. For this investigation, 12,866 men, ages thirty-five to fifty-seven years, have been enrolled, after having been identified at increased risk because of a combination of risk factors: Elevated serum cholesterol, elevated diastolic blood pressure, and cigarette smoking. MRFIT provides an excellent opportunity for nutritionists to work closely with physicians, behavioral scientists, nurses, and other scientists in a program to change food habits, reduce blood pressure, and achieve cessation of smoking.