Peter J. Hannan

Low Heart Rate Variability in a 2-Minute Rhythm Strip Predicts Risk of Coronary Heart Disease and Mortality From Several Causes The ARIC Study

BackgroundLow heart rate variability (HRV) is associated with a higher risk of death in patients with heart disease and in elderly subjects and with a higher incidence of coronary heart disease (CHD) in the general population. Methods and ResultsWe studied the predictive value of HRV for CHD and death from several causes in a population study of 14 672 men and women without CHD, aged 45 to 65, by using the case-cohort design. At baseline, in 1987 to 1989, 2-minute rhythm strips were recorded. Time-domain measures of HRV were determined in a random sample of 900 subjects, for all subjects with incident CHD (395 subjects), and for all deaths (443 subjects) that occurred through 1993. Relative rates of incident CHD and cause-specific death in tertiles of HRV were computed with Poisson regression for the case-cohort design. Subjects with low HRV had an adverse cardiovascular risk profile and an elevated risk of incident CHD and death. The increased risk of death could not be attributed to a specific cause and could not be explained by other risk factors. ConclusionsLow HRV was associated with increased risk of CHD and death from several causes. It is hypothesized that low HRV is a marker of less favorable health.

Weight-teasing among adolescents: Correlations with weight status and disordered eating behaviors

OBJECTIVES: This study aimed to assess the prevalence of perceived weight-teasing and associations with unhealthy weight-control behaviors and binge eating in a population-based sample of youth. Particular focus was placed on overweight youth, who may be most vulnerable to weight-teasing.METHODS: The study population included 4746 adolescents from St Paul/Minneapolis public schools who completed surveys and anthropometric measurements as part of Project EAT, a population-based study of eating patterns and weight concerns among teens.RESULTS: There were statistically significant associations between perceived weight-teasing and weight status; both overweight and underweight youth reported higher levels of teasing than average weight youth. Very overweight youth (body mass index (BMI) ≥95th percentile) were most likely to be teased about their weight; 63% of very overweight girls, and 58% of very overweight boys reported being teased by their peers, while weight-teasing by family members was reported by 47% of these girls and 34% of these boys. Youth who were teased about their weight, particularly overweight girls, reported that it bothered them. Perceived weight-teasing was significantly associated with disordered eating behaviors among overweight and non-overweight girls and boys. For example, among overweight youth, 29% of girls and 18% of boys who experienced frequent weight-teasing reported binge-eating as compared to 16% of girls and 7% of boys who were not teased.CONCLUSIONS: Many adolescents, in particular those who are overweight, report being teased about their weight and being bothered by the teasing. Weight-teasing is associated with disordered eating behaviors that may place overweight youth at increased risk for weight gain. Educational interventions and policies are needed to curtail weight-related mistreatment among youth.

Pricing and Promotion Effects on Low-Fat Vending Snack Purchases: The CHIPS Study.

OBJECTIVES This study examined the effects of pricing and promotion strategies on purchases of low-fat snacks from vending machines. METHODS Low-fat snacks were added to 55 vending machines in a convenience sample of 12 secondary schools and 12 worksites. Four pricing levels (equal price, 10% reduction, 25% reduction, 50% reduction) and 3 promotional conditions (none, low-fat label, low-fat label plus promotional sign) were crossed in a Latin square design. Sales of low-fat vending snacks were measured continuously for the 12-month intervention. RESULTS Price reductions of 10%, 25%, and 50% on low-fat snacks were associated with significant increases in low-fat snack sales; percentages of low-fat snack sales increased by 9%, 39%, and 93%, respectively. Promotional signage was independently but weakly associated with increases in low-fat snack sales. Average profits per machine were not affected by the vending interventions. CONCLUSIONS Reducing relative prices on low-fat snacks was effective in promoting lower-fat snack purchases from vending machines in both adult and adolescent populations.

Ethnic/racial differences in weight-related concerns and behaviors among adolescent girls and boys Findings from Project EAT

OBJECTIVE To compare weight-related concerns and behaviors across ethnicity/race among a population-based sample of adolescent boys and girls. METHODS The study population included 4746 adolescents from urban public schools in the state of Minnesota who completed surveys and anthropometric measurements as part of Project EAT (Eating Among Teens), a population-based study focusing on eating patterns and weight concerns among teenagers. Main outcome measures included measured body mass index (BMI), weight-related concerns (perceived weight status, weight disparity, body satisfaction and attitudes about weight control) and weight-related behaviors (general/specific weight control behaviors and binge eating). RESULTS In comparison to White girls, African American girls tended to report fewer weight-related concerns/behaviors, while Hispanic, Asian American and Native American girls tended to report similar or more concerns/behaviors. Among boys, weight-related concerns/behaviors were equally or more prevalent among all non-Whites than among Whites. In particular, African American and Asian American boys were at greater risk for potentially harmful weight-related concerns/behaviors than White boys. CONCLUSIONS Weight-related concerns and behaviors are prevalent among adolescents, regardless of their ethnic/racial background, indicating a need for prevention and treatment efforts that reach adolescents of different ethnic backgrounds. However, ethnic differences demonstrate a need for ensuring that the specific needs of different groups are addressed in the development of such interventions.

Longitudinal and Secular Trends in Physical Activity and Sedentary Behavior During Adolescence

OBJECTIVE. There is little epidemiologic research on longitudinal and secular trends in weight-related health behaviors throughout the stages of adolescence. In particular, few data are available to assess secular trends in various sedentary behaviors. The objective of this research was to investigate longitudinal and secular trends in physical activity and sedentary behavior in a large, diverse cohort of adolescents. METHODS. Project EAT-II is a 5-year longitudinal study (N = 2516) that includes 2 cohorts that allow for the observation of longitudinal changes from early to midadolescence (junior high to high school; n = 806; mean baseline age: 12.8 ± 0.8 years) and mid- to late adolescence (high school to post–high school; n = 1710; mean baseline age: 15.8 ± 0.8 years). EAT-II also examined secular trends in health behavior from 1999 to 2004 in midadolescence. The main outcome measures of the mixed-model regression analyses used in this research were self-reported weekly hours of moderate to vigorous physical activity, television/video viewing, and leisure-time computer use. RESULTS. Our findings indicate substantial longitudinal changes in moderate to vigorous physical activity, particularly among girls (decreasing 5.9–4.9 hours/week from early to midadolescence and 5.1–3.5 hours/week from mid- to late adolescence), and leisure-time computer use, particularly among boys (increasing 11.4–15.2 hours/week from early to midadolescence and 10.4–14.2 hours/week from mid- to late adolescence). Secular trends further indicate dramatic increases in midadolescent computer use from 1999 to 2004; girls increased from 8.8 to 11.1 hours/week, and boys increased from 10.4 to 15.2 hours/week. CONCLUSIONS. These adolescents experienced unfavorable shifts in activity patterns, such as longitudinal decreases in moderate to vigorous physical activity, coupled with longitudinal and secular increases in leisure-time computer use. Developing effective health promotion strategies that address a wide array of changing behavioral patterns will be important in promoting long-term health and active lifestyles among adolescents and young adults.

Overweight Status and Eating Patterns Among Adolescents: Where Do Youths Stand in Comparison With the Healthy People 2010 Objectives?

OBJECTIVES This study determined the prevalence of Minnesota urban youths reaching the Healthy People 2010 objectives for obesity and intake of fat, calcium, fruits, vegetables, and grains and compared prevalence rates across sociodemographic characteristics. METHODS The study sample included 4746 adolescents (aged 11-18 years) from the Minneapolis/St. Paul area who completed dietary surveys and participated in anthropometric measurements as part of a school-based population study. RESULTS Considerable gaps were seen between the existing prevalence rates for obesity and nutrient and food patterns and the targeted Healthy People 2010 prevalence rates. For example, 12.5% of the girls and 16.6% of the boys had body mass index values at or greater than the 95th percentile (target = 5%). Only 29.5% of the girls and 42.5% of the boys were meeting the daily recommended intakes for calcium (target = 75%). Similarly, percentages of youths consuming the recommended amounts of fat, fruits, vegetables, and grains were lower than the targeted percentages. There were large sociodemographic disparities in obesity and eating patterns, particularly across race/ethnicity and socioeconomic status. CONCLUSIONS Concerted public health efforts are needed to achieve the Healthy People 2010 objectives for obesity and nutrition and to reduce racial/ethnic and socioeconomic disparities.

Body Dissatisfaction Prospectively Predicts Depressive Mood and Low Self-Esteem in Adolescent Girls and Boys

This research examined whether body dissatisfaction prospectively predicted depressive mood and low self-esteem in adolescent girls and boys 5 years later. Participants were early-adolescent girls (n = 440, Time 1 M age = 12.7 years) and boys (n = 366, Time 1 M age = 12.8 years) and midadolescent girls (n = 946, Time 1 M age = 15.8 years) and boys (n = 764, Time 1 M age = 15.9 years). After controlling for Time 1 of the relevant dependent variable, ethnicity, socioeconomic status, and body mass index, Time 1 body dissatisfaction was a unique predictor of Time 2 depressive mood and low self-esteem in early-adolescent girls (depressive mood: F = 4.80, p < .05; self-esteem: F = 9.64, p < .01) and midadolescent boys (depressive mood: F = 12.27, p < .001; self-esteem: F = 9.38, p < .01) but not in early-adolescent boys or midadolescent girls. These findings are consistent with the hypothesis that body dissatisfaction is a risk factor for depressive mood and low self-esteem in both girls and boys but in different phases of adolescence.

New Moves: a school-based obesity prevention program for adolescent girls.

BACKGROUND This study tests the feasibility of an innovative school-based program for obesity prevention among adolescent girls. New Moves was implemented as a multicomponent, girls-only, high-school physical education class. METHODS Six schools were equally randomized into intervention and control conditions. Data were collected at baseline, postintervention, and 8-month follow-up to assess program impact on physical activity, eating patterns, self-perceptions, and body mass index (BMI) among 89 girls in the intervention and 112 girls in the control conditions. Program evaluation also included interviews with school staff, parent surveys, and participant interviews and process evaluation surveys. RESULTS The feasibility of implementing New Moves was high, as indicated by strong satisfaction among participants, parents, and school staff, and by program sustainability. Participants perceived a positive program impact on their physical activity, eating patterns, and self-image. Girls in the intervention significantly progressed in their stage of behavioral change for physical activity from baseline to follow-up. However, for the majority of outcome variables, differences between intervention and control schools at postintervention and follow-up were not statistically significant. CONCLUSIONS New Moves was well received and fills a needed niche within school physical education programs. An expanded intervention and evaluation is needed to enhance and assess long-term program effectiveness.

Effects of Thiazide Diuretics on Plasma Lipids and Lipoproteins in Mildly Hypertensive Patients: A Double-Blind Controlled Trial

A blood lipid-lipoprotein elevating effect of the diuretics hydrochlorothiazide and chlorthalidone in mildly hypertensive men has been established by a cross-over, randomized controlled trial, confirming previous clinical observations. Compared to baseline, plasma total cholesterol increased 6% and 8% and triglycerides 17% and 15% under treatment with hydrochlorothiazide and chlorthalidone, respectively. A cholesterol-lowering diet largely prevents this increase. Because these effects may be long-lasting and may cancel part of the potential benefit of blood pressure control in mildly hypertensive patients, with thiazide diuretics attention should be given to prescription of a cholesterol-lowering diet and to periodic monitoring of blood lipid levels. Different antihypertensive agents might be considered in patients with elevated blood lipid levels. Other antihypertensive agents currently in use need to be studied for potential effects on lipid metabolism.

A pricing strategy to promote low-fat snack choices through vending machines

OBJECTIVES This study examined the role of price on purchases of low-fat snacks from vending machines. METHODS Sales of low-fat and regular snacks were monitored in nine vending machines during a 4-week baseline, a 3-week intervention in which prices of low-fat snacks were reduced 50%, and 3 weeks postintervention. RESULTS The proportion of low-fat snacks purchased was 25.7%, 45.8%, and 22.8% in the three periods, respectively. Total snack purchases did not vary by period. CONCLUSIONS Reducing relative prices may be effective in promoting lower-fat food choices in the population. Vending machines may be a feasible method for implementing such nutrition interventions.