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C Bragg

Publications and source records attributed to C Bragg.

13 recordsLinked to original sources
PubMed2001

Long-term weight loss and changes in blood pressure: results of the Trials of Hypertension Prevention, phase II.

BACKGROUND: Weight loss appears to be an effective method for primary prevention of hypertension. However, the long-term effects of weight loss on blood pressure have not been extensively studied. OBJECTIVE: To present detailed results from the weight loss arm of Trials of Hypertension Prevention (TOHP) II. DESIGN: Multicenter, randomized dinical trial testing the efficacy of lifestyle interventions for reducing blood pressure over 3 to 4 years. Participants in TOHP II were randomly assigned to one of four groups. This report focuses only on participants assigned to the weight loss (n = 595) and usual care control (n = 596) groups. PATIENTS: Men and women 30 to 54 years of age who had nonmedicated diastolic blood pressure of 83 to 89 mm Hg and systolic blood pressure less than 140 mm Hg and were 110% to 165% of their ideal body weight at baseline. INTERVENTION: The weight loss intervention included a 3-year program of group meetings and individual counseling focused on dietary change, physical activity, and social support MEASUREMENTS: Weight and blood pressure data were collected every 6 months by staff who were blinded to treatment assignment RESULTS: Mean weight change from baseline in the intervention group was -4.4 kg at 6 months, -2.0 kg at 18 months, and -0.2 kg at 36 months. Mean weight change in the control group at the same time points was 0.1, 0.7, and 1.8 kg. Blood pressure was significantly lower in the intervention group than in the control group at 6, 18, and 36 months. The risk ratio for hypertension in the intervention group was 0.58 (95% CI, 0.36 to 0.94) at 6 months, 0.78 (CI, 0.62 to 1.00) at 18 months, and 0.81 (CI, 0.70 to 0.95) at 36 months. In subgroup analyses, intervention participants who lost at least 4.5 kg at 6 months and maintained this weight reduction for the next 30 months had the greatest reduction in blood pressure and a relative risk for hypertension of 0.35 (CI, 0.20 to 0.59). CONCLUSIONS: Clinically significant long-term reductions in blood pressure and reduced risk for hypertension can be achieved with even modest weight loss.

Adult↗
PubMed1998

Design of "High 5": a school-based study to promote fruit and vegetable consumption for reduction of cancer risk.

BACKGROUND: This paper describes the methods used in "High 5," a school-based study to increase fruit and vegetable consumption for cancer risk reduction. METHODS: Twenty-eight elementary schools were matched and randomized to intervention or control conditions. All students were assessed based on diet and psychosocial variables at baseline and one and two years post-baseline. The intervention included classroom, parent, and environmental components. RESULTS: The study recruited 1,698 families and retained 85%. The two conditions were equivalent at baseline; 50% female students, 81% to 84% European-American students, and 2.9 servings of fruit and vegetables per day. Good completion was achieved across the intervention components (e.g., 90% of lessons taught, 72% of parent materials read, 3.6 servings of fruit and vegetables offered in cafeterias). CONCLUSIONS: The use of school-based programs, with strong evaluation designs, will enhance knowledge about the modification of nutrition behavior and cancer risk in children. Lessons learned from the study are reported.

Analysis of Variance↗
PubMed1994

A study of the reliability and comparative validity of the cardia dietary history.

This study evaluated the reliability and comparative validity of the dietary history survey method developed for CARDIA, a longitudinal investigation of life-styles and the evolution of cardiovascular risk factors in young adults. The method was tested in a sample of 30 white men, 33 white women, 33 black men, and 32 black women, aged 18 to 35 years, in four regions reflecting the race, sex, age, and geographical distribution of CARDIA participants. For 64 of the participants, two dietary history interviews, 1 month apart, were conducted by trained nutritionists. These data were used to examine the reliability of the method. For all participants, seven telephone- assessed 24-hour dietary recalls were randomly scheduled during a 28-day period and were followed by a dietary history interview. These data were used to examine the comparative validity of the method. Calories, total fat, saturated fat, polyunsaturated fat, monounsaturated fat, dietary cholesterol, protein, carbohydrate, alcohol, potassium, calcium, and vitamin A were selected by the CARDIA Nutrition Working Group as the nutrients for comparison. Mean nutrient values from the first history tended to be higher than those obtained from the last history. However, for a majority of the nutrients, the differences were significant for blacks but not for whites. The correlations for the log-transformed nutrient values and calorie-adjusted nutrient values from the two histories were generally in the range of 0.50 to 0.80 for whites. For blacks, the correlations were lower, with a majority in the range of 0.30 to 0.70. The average nutrient values estimated from the histories were higher than those estimated from the average of the seven 24-hour recalls. The differences in blacks were larger than in whites. For both the log-transformed nutrient values and the calorie-adjusted nutrient values, the correlations between the two methods were generally larger than 0.50 for whites. However, for blacks, the correlations were lower, and for several macronutrients, the correlations were close to zero. These results suggest that the CARDIA dietary history is a reasonably reliable and valid dietary survey method for obtaining information about habitual intakes in whites. In blacks, the results are less consistent. The black-white differences remained when the analyses were stratified by education. These results raise a question about differences in reporting between blacks and whites.

Adolescent↗
PubMed1993

Inconsistent associations of caffeine-containing beverages with blood pressure and with lipoproteins. The CARDIA Study. Coronary Artery Risk Development in Young Adults.

The authors examined associations of caffeine and caffeinated beverage intakes with blood pressure and with lipoproteins in 5,115 black and white men and women aged 18-30 years during 1985-1986. Caffeine and beverage intakes were not consistently associated with blood pressure in analyses controlling for race, sex, Keys score, sucrose intake, physical activity, oral contraceptive use, body mass index, alcohol use, age, and smoking. Associations of caffeine and beverage intakes with cholesterol, triglycerides, high-density lipoprotein cholesterol, and high-density lipoprotein2 cholesterol were also inconsistent. There is little or no association of caffeine with lipoproteins or with blood pressure in this cohort of healthy young adults.

Adolescent↗
PubMed1992

Quality control of dietary data collection in the CARDIA study.

The Coronary Artery Risk Development in (Young) Adults (CARDIA) Study developed and implemented quality control (QC) measures to minimize misclassification associated with dietary data. Manual and automated data inspection were used to monitor quality. Of the 5111 participants who completed a dietary history, 717 (14%) had dietary forms reviewed and 153 (3%) had the interview audiotaped. Results show that for the 717 forms reviewed, the overall form completion error rate was 0.22% and the "critical" error rate (i.e., those errors impacting on nutrient computations) was 0.12%. The proportion of forms free of any type of error increased over time (p less than 0.0001). The discrepancy rate in recording and interviewing methods as estimated from the 153 audiotaped interviews was 0.7%. Inter-interviewer differences were small as indicated by the audiotaped interviews and the proportion of error-free forms completed by interviewers. The results indicate that the dietary data collected in CARDIA were completely and accurately recorded for use in analysis.

Adolescent↗
PubMed1991

Meat consumption and its associations with other diet and health factors in young adults: the CARDIA study.

Using cross-sectional data from the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) study, we assessed associations between meat consumption and other dietary- and health-status indicators. Less than one percent of this sample (n = 32) ate no red meat or poultry, and another 1% (n = 47) ate red meat or poultry less than once per week. Individuals who ate red meat and poultry less than once per week were less likely to drink alcohol (P = 0.003); reported more physical activity (P less than or equal to 0.001); had lower [corrected] Keys scores (P less than or equal to 0.001); consumed diets higher in carbohydrates, starch, fiber, vitamins A and C, and calcium and lower in energy, fat, and protein (P less than or equal to 0.001); had smaller body sizes as indicated by the body mass index [calculated as wt(kg)/ht(m2)] (P = 0.01); and had lower concentrations of total serum cholesterol (P = 0.001), low-density-lipoprotein cholesterol (P = 0.001), and triglycerides (P = 0.015) compared with individuals who consumed meat more frequently.

Adult↗
PubMed1991

Diet, body size, and plasma lipids-lipoproteins in young adults: differences by race and sex. The Coronary Artery Risk Development in Young Adults (CARDIA) study.

The Coronary Artery Risk Development in Young Adults (CARDIA) study completed baseline dietary assessment, measurement of body mass index, and lipid and lipoprotein analyses on 5,111 participants. CARDIA includes black and white men and women between 18 and 30 years of age at baseline (1985-1986), recruited in Birmingham, Alabama, Chicago, Illinois, Minneapolis, Minnesota, and Oakland, California. Diet was assessed by a detailed interviewer-administered diet history that measured the usual eating pattern over the past month. Possible sex, race, age, and educational differences in diet, body size, and lipids-lipoproteins were explored. Nutrient analyses indicate that the Keys score, a measure of dietary fat composition, is significantly correlated with plasma cholesterol in older (aged 25-30 years) white men (r = 0.12, p less than 0.01) and older white women (r = 0.12, p less than 0.001). In multiple linear regression analyses, body mass index was positively and significantly associated with total cholesterol and low density lipoprotein cholesterol and inversely associated with high density lipoprotein cholesterol across all race-sex groups. The Keys score was significantly associated with total cholesterol and low density lipoprotein cholesterol in white men and women. Education was associated with high density lipoprotein cholesterol in black and white women and white men. In these young adults, dietary fat intake and body mass index were related to blood lipids in certain subgroups. In black and white men and black women, blood cholesterol increased with age across race-sex groups independently of these covariates. In view of the many factors affecting plasma cholesterol and the limitations of the dietary history method, these cross-sectional data are useful in characterizing diet and lipid differences. There appears to be general disparity between recommended dietary intake of total fat, saturated fat, and other nutrients and actual dietary intake in young adults, regardless of age and educational level.

Adolescent↗
PubMed1991

The CARDIA dietary history: development, implementation, and evaluation.

To meet the objectives for dietary assessment in the Coronary Artery Risk Development in Young Adults (CARDIA) prospective study, we developed a dietary history to provide accurate and reliable quantitative data on habitual individual nutrient intakes at baseline. The CARDIA dietary history was an interviewer-administered method that included a short questionnaire regarding general dietary practices followed by a comprehensive food frequency questionnaire about typical intake of foods using the previous month as a reference for recall. For each broad category of foods, participants were questioned in detail about specific foods only if they indicated that they consumed foods from that category. Follow-up questions for selected foods concerned serving size, frequency of consumption, and common additions to these foods. Provision was made for reporting foods not found in the food frequency list. The interview took approximately 45 minutes. Cue cards prompted responses and plastic food models assisted in estimating usual amounts consumed. A precoded format standardized coding for reported items and established the detail needed for recall during the interview. Baseline nutrient analyses from the CARDIA dietary history provided estimates that agreed reasonably well with expected caloric intake for body mass index according to the age- and sex-specific Recommended Dietary Allowances, but were higher than those reported from 24-hour recalls for comparable age, sex, and race groups in the second National Health and Nutrition Examination Survey. The CARDIA dietary history is a comprehensive assessment tool that can provide a dietitian with detailed information regarding habitual eating patterns and nutrient intakes among adults.

Adult↗