Participants' evaluation of a weight-loss program.

OBJECTIVE: The purpose of this study was to evaluate participants' perceptions of the weight-loss intervention used in a hypertension prevention clinical trial. DESIGN: A total of 308 overweight and moderately obese subjects participated in the weight-management intervention. After the 18-month program, 281 participants completed a questionnaire designed to evaluate their perceptions of the program's effectiveness. SUBJECTS/SETTING: Adult participants (224 men and 84 women) in the weight-loss modality of the Trials of Hypertension Prevention Phase I, surveyed in 1991. STATISTICAL ANALYSES PERFORMED: chi 2 Analyses were used to test for statistical significance of group differences. RESULTS: Intervention components that were most useful are presented. Older participants (older than 50 years) were most likely to attend sessions and women were most likely to identify stress and frustration because of disappointing results. Successful participants were more likely to incorporate exercise into their daily activities, exercise regularly, and use self-monitoring strategies. Few participants found group exercise to be useful. CONCLUSION: These findings suggest that interventionists in weight-loss programs need to find flexible and creative ways to maintain contact with participants, continue to develop better methods of self-monitoring, obtain the skills needed to recognize frustration and provide timely support, continue to couple the message of diet and exercise, and emphasize helping participants develop their problem-solving skills. This may require training outside the traditional field of dietetics.

Feasibility and efficacy of sodium reduction in the Trials of Hypertension Prevention, phase I. Trials of Hypertension Prevention Collaborative Research Group.

Phase I of the Trials of Hypertension Prevention was a multicenter, randomized trial of the feasibility and efficacy of seven nonpharmacologic interventions, including sodium reduction, in lowering blood pressure in 30- to 54-year-old individuals with a diastolic blood pressure of 80 to 89 mm Hg. Six centers tested an intervention designed to reduce dietary sodium to 80 mmol (1800 mg)/24 h with a total of 327 active intervention and 417 control subjects. The intervention consisted of eight group and two one-to-one meetings during the first 3 months, followed by less-intensive counseling and support for the duration of the study. The mean net decrease in sodium excretion was 43.9 mmol/24 h at 18 months. Women had lower sodium intake at baseline and were therefore more likely to decrease to less than 80 mmol/24 h. Black subjects were less likely to decrease to less than 80 mmol/d, independent of sex or baseline sodium excretion. The mean (95% confidence interval) net decrease associated with treatment was -2.1 (-3.3, -0.8) mm Hg for systolic blood pressure and -1.2 (-2.0, -0.3) mm Hg for diastolic blood pressure at 18 months (both P < .01). Multivariate analyses indicated a larger systolic blood pressure effect in women (-4.44 versus -1.23 mm Hg in men), adjusted for age, race, baseline blood pressure, and baseline 24-hour urinary sodium excretion (P = .02). Dose-response analyses indicated an adjusted decrease of -1.4 mm Hg for systolic blood pressure and -0.9 mm Hg for diastolic blood pressure for a decrease of 100 mmol/24 h in 18-month sodium excretion. These results support the utility of sodium reduction as a population strategy for hypertension prevention and raise questions about possible differences in dose response associated with gender and initial level of sodium intake.

Weight loss intervention in phase 1 of the Trials of Hypertension Prevention. The TOHP Collaborative Research Group.

BACKGROUND: Phase 1 of the Trials of Hypertension Prevention was a collaborative, randomized controlled clinical trial designed to determine the feasibility and efficacy of selected nonpharmacologic interventions in reducing or preventing an increase in diastolic blood pressure. METHODS: Participants aged 30 to 54 years who had a high-normal diastolic blood pressure (80 to 89 mm Hg), and were between 115% and 165% of their desirable body weight, were randomly assigned to either an 18-month weight loss intervention (n = 308) or a usual-care control condition (N = 256). Intervention consisted of 14 weekly group meetings followed by monthly maintenance sessions. Intervention participants received training in behavioral self-management technique and were asked to make life-style changes aimed at achieving a moderate reduction in energy intake and an increase in physical activity. RESULTS: The average weight losses in the intervention group at 6, 12, and 18 months of follow-up were 6.5, 5.6, and 4.7 kg for men and 3.7, 2.7, and 1.6 kg for women. The mean (+/- SE) change in diastolic blood pressure for intervention participants compared with controls at termination was -2.8 +/- 0.6 mm Hg for men and -1.1 +/- 0.9 mm Hg for women. For systolic blood pressure, the corresponding change was -3.1 +/- 0.7 mm Hg for men and -2.0 +/- 1.3 mm Hg for women. Blood pressure reductions were greater for those who lost larger amounts of weight. Sex-related differences in blood pressure response were largely due to the smaller amount of weight lost by women, and sex differences in weight loss could be accounted for by differences in baseline body weight. CONCLUSIONS: During an 18-month follow-up period, this weight reduction program was shown to be an effective nonpharmacologic intervention for reducing blood pressure in overweight adults with high-normal blood pressure.

Treatment in the Hypertension Prevention Trial. Hypertension Prevention Trial Research Group.

The Hypertension Prevention Trial (HPT) was a randomized, controlled, multicenter (four clinics, four resource centers) trial designed to test the feasibility of achieving and sustaining dietary changes in the intake of calories, sodium, and potassium and to assess the effect of those changes on blood pressure in a normotensive population. The trial involved 841 men and women (plus a test cohort of 78) who, at the first baseline (BL) examination were in the age range of 25-49 years and had diastolic blood pressure (DBP) greater than or equal to 76 but less than 100 mm Hg (average of two readings), and at the examination prior to randomization (BL 2) had DBP greater than or equal to 78 but less than 90 mm Hg (also averaged). Participants were randomly assigned to a control treatment group (no dietary counseling) or to one of four dietary treatment groups involving counseling designed to reduce calorie intake, reduce sodium intake, reduce sodium and calorie intake, and reduce sodium and increase potassium intake. This chapter describes the counseling methods employed to help participants achieve the desired dietary changes. Counseling was provided to groups by trained interventionists and included instruction in food selection, food preparation, and behavior management skills. Counseling groups met weekly for the first 10 weeks of the trial, twice the following month, and bimonthly thereafter. Techniques used in the counseling program included group discussions, instructions for dietary record keeping, goal setting, individual diet analysis for each participant, cooking demonstrations, and taste testing of new foods.