Results of a Three-Year Community Study - NCBI - NIH

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Nov 29, 1982 - adult women's groups which strive to improve homemaking skills) in Harris County ... Spouses and friends of club members were also encouraged to join. ... sion Service of the Texas A&M University System. Address reprint ...
Effects of a Low Cholesterol Eating Plan on Plasma Lipids: Results of a Three-Year Community Study REBECCA S. REEVES, MPH, RD, JOHN P. FOREYT, PHD, LYNNE W. SCOTT, MA, RD, ROBERT E. MITCHELL, PHD, JAMES WOHLLEB, MS, AND ANTONIO M. GOTTO, JR., MD Abstract: In an attempt to demonstrate whether individuals with average plasma lipids would accept a diet low in saturated fat and cholesterol, members of a community organization were taught the HELP Your Heart Eating Plan. Results of 282 individuals suggest that reduced dietary cholesterol from selected foods could be sustained for up to 36 months. While both plasma cholesterol and

triglycerides fell during a year of instruction, both rose to above initial values by 36 months. Overall, the results suggest that adults may be willing to accept a new style of eating temporarily but are not committed to making permanent dietary changes. (Am J Public Health 1983; 73:873-877.)

Introduction Various authoritative groups'.2 including the Steering Committee for the Medical and Community Program of the American Heart Association3 have recommended that the American public follow a diet aimed at lowering plasma cholesterol and maintaining ideal body weight. The majority of studies demonstrating the effect of diet on lowering serum cholesterol levels have been conducted with patients in institutions,45 people with abnormally high lipids,-8 or individuals who already have coronary heart disease.-" The results of these studies tell us little about the acceptance of low-cholesterol diets by free-living, normolipemic community members. In the few investigations'2-'4 that have attempted to study free-living populations, results have been equivocal. Most of them included individualized diet instructions and counseling and as such are not cost-effective in reaching large numbers of people. The Stanford Three Community Study'5-'7 attempted to influence dietary habits primarily through the use of media, including public service announcements on radio and television, a newspaper column, and direct mailings to participants. Lipid results were disappointing, with mean plasma cholesterol lowering of about 1 per cent at one year post-treatment in the most successful group. The present study was designed to determine whether free-living groups of individuals with average plasma lipids would accept a diet low in saturated fat and cholesterol.

more women than men were able to attend the programs. The study was explained to them, and interested individuals signed informed consent forms. A total of 409 persons initially enrolled, 292 females and 117 males. Demographic data on the original 409 participants and those who completed the 12-, 24-, and 36-month blood visits are presented in Table 1. Nine participants were excluded because they were taking lipid altering medications. The average initial triglyceride for this group was 161 mg/dl compared to 133 mg/dl for the remaining 400 participants; their average initial cholesterol was 256 mg/dl while the average initial cholesterol for the remaining 400 participants was 217 mg/dl. Educational Materials

Educational materials were designed to teach participants how to decrease their intake of cholesterol and saturated fat. These materials included the HELP Your Heart Eating Plan'8 and the Brand Name Shopper's Guide'9 (a booklet listing commercial products allowed on the Eating Plan). Educational pamphlets providing supplementary diet information and a cookbook were also used. The HELP Your Heart Eating Plan recommends that no more than 35 per cent of total calories come from fat (no more than 10 per cent from saturated [S] fat, at least 10 per cent from polyunsaturated [P], and the remainder from monounsaturated fat, with a P/S of 1.0). Dietary cholesterol is limited to 300 mg per day. Calories are adjusted to achieve and maintain ideal body weight.

Methods

Procedure

Population

During the initial 12 months (the primary intervention period) the cookbook and pamphlets were mailed monthly to all individuals to help maintain their awareness of the study. In the spring and fall, participants were invited to attend two cooking demonstrations conducted by a home economist who prepared foods and demonstrated cooking techniques recommended by the eating plan. Tasting sessions followed the demonstrations and copies of the recipes were distributed. Media coverage of the HELP Your Heart program publicized the study to the Houston community. The daily morning newspaper printed an article with photographs of the first group of participants joining the study. The cooking demonstrations were written up in the daily afternoon newspaper. Suburban newspapers regularly carried articles on local Home Demonstration Clubs in their area and their involvement in the program. The state publication of the Texas Home Demonstration Association printed a story

With the cooperation of the Texas Agricultural Extension Service, all 16 Home Demonstration Clubs (organized adult women's groups which strive to improve homemaking skills) in Harris County (Houston), Texas (total membership approximately 420) were invited to participate in this study. Spouses and friends of club members were also encouraged to join. However, since meetings occurred during the day, From the Diet Modification Section of the National Heart and Blood Vessel Research and Demonstration Center, Baylor College of Medicine and The Methodist Hospital, Houston, Texas, and the Texas Agricultural Extension Service of the Texas A&M University System. Address reprint requests to Rebecca S. Reeves, MPH, RD, Diet Modification Clinic, 6535 Fannin, M.S. F-700, Houston, TX 77030. This paper, submitted to the Journal November 23, 1981, was revised and accepted for publication November 29, 1982.

© 1983 American Journal of Public Health, 0090-0036/83 $1.50

AJPH August 1983, Vol. 73, No. 8

873

REEVES, ET AL. TABLE 1-Characteristics of Sample Population

Characteristics Sex Male Female Race/Ethnicity White Black Mexican-American Marital Status Married Separated Divorced Widowed Never married Mean Age (years)

Original Sample n 117 292

0, 12, 24, 26 Month Sample

(n = 409)

(n =

282)

% 28.6 71.4

n 70 212

376 29 4

91.9 7.1 1.0

256 24 2

90.8 8.5 0.7

336 3 6 59 5 53.7

82.2 0.7 1.5 14.4 1.2

231 2 1 44 4 56.6

81.9 0.7 0.3 15.6

% 24.8 75.2

1.4

about the participation of the Harris County clubs, accompanied by pictures on the magazine cover. A registered dietitian presented one-hour nutrition education programs to each of the 16 clubs four times during the first 12 months and again at the 24-month and 36-month follow-up periods. The initial visit was conducted in January and February, the 3-month visit in April and May, the 6month visit during July and August, and the 12-month visit the following January and February. The 24-month and 36month follow-up visits were held during January and February of the following two years. At the initial visit, the dietitian instructed club members how to modify their eating habits in order to follow the eating plan. During the 3-month visit she showed a film on how to read and interpret nutrition labeling especially as it related to the eating plan. Food labels were distributed and discussed. At the 6-month visit, basic principles of the eating plan were reviewed and reemphasized. The dietitian presented a program on weight control at the 12-month visit which included an explanation of the low calorie eating plan and basic behavior modification principles. These behavioral principles included training in self-monitoring, stimulus control, and contingency management.20 During the 24-month follow-up visit, the dietitian presented the lipid results of the study from the first year. Participants completed a food quiz covering principles of the eating plan, followed by group discussion of the answers. To conclude the visit, a slide tape show on "Special Occasions" was shown. At the 36-month follow-up visit, the dietitian presented the lipid results that the study had generated over the past two years. Another food quiz was administered and discussed on a group basis. Measures Before each educational program (initial, 3, 6, 12, 24, and 36-months), a 12 to 14-hour fasting blood sample was collected from each participant in a 15 ml tube containing EDTA as an anticoagulant. Total plasma cholesterol and triglyceride concentrations were determined from a Zeolitetreated isopropanol extract of plasma analyzed by an Auto Analyzer II following the procedures described in the Lipid Research Clinics Manual of Laboratory Operations.2' At each visit weight, blood pressure, and triceps skinfold were measured; height was measured at first visit only. Blood pressure was taken while the subject was seated after 15 874

minutes of rest. Triceps skinfold was measured to the nearest 0.5 mm with a Lange skinfold caliper at the midpoint of the triceps. In a questionnaire containing a food freqency table, participants were asked to indicate the number of servings (serving size was indicated) of each of 19 food groups they ate either daily, weekly, monthly, or yearly. The majority of husbands reported around 6:00 am before going to work. Most of the women participants arrived at 9:00 am and remained afterwards for the meetings. Lipid results were mailed to participants and their private physicians if requested by the participants. Results Data from the participants who attended all four of the yearly evaluation sessions were analyzed. Results from the 3- and 6-month evaluations are reported elsewhere.22 Possible differences with respect to lipids between those who dropped out after the initial evaluation or after the 24-month evaluation and those who remained in the program were investigated by 3-way analyses of variance (ANOVA) with drop-out status, age group, and sex as the three factors. There were too few drop-outs at 12 months to permit an analysis. Results revealed that there were no differences in lipids attributable to drop-outs (both Fs < 1.00).

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.05). Older subjects generally lost more weight and retained their loss longer than younger subjects. At 36 months, weights of those