Assault Deterrents and Educators' Risk of Physical Assault: A Case-Control Study.

The study purpose was to identify associations between assault deterrent presence in kindergarten through 12th (K-12) grade schools and physical assaults (PAs) against educators. Data collected through a two-phase study identified physical and nonphysical violent events and utilized a nested case-control study to identify PA risk/protective factors. Analyses included multivariable modeling. Adjusted analyses demonstrated a significant decreased risk of PA with routine locker searches (odds ratio [OR] = 0.49, 95% confidence interval [CI] [0.29, 0.82]). Also important, although not statistically significant, were presence of video monitors (OR = 0.72, 95% CI [0.50, 1.03]), intercoms (OR = 0.77, 95% CI [0.55, 1.06]), and required school uniforms/dress codes (OR = 0.74, 95% CI [0.52, 1.07]). These findings are integral to school nursing practice in which there is opportunity to influence application of relevant pilot intervention efforts as a first step in determining the potential efficacy of broad-based interventions that can positively impact the problem of school-related violence.

Bi-Directional Associations Between Real-Time Affect and Physical Activity in Weight-Discordant Siblings.

Pediatric obesity confers increased risk for a host of negative psychological and physical health consequences and is reliably linked to low levels of physical activity. Affective antecedents and consequences of physical activity are thought to be important for the development and maintenance of such behavior, though research examining these associations in youth across the weight spectrum remains limited. OBJECTIVE: This study examined bi-directional associations between affect and physical activity (i.e., moderate-to-vigorous physical activity [MVPA] and total activity counts), and the extent to which weight (body mass index z-score [z-BMI]) moderated these associations. METHODS: Participants were drawn from a prior study of siblings (N = 77; mean age = 15.4 ± 1.4 years) discordant for weight status (39 nonoverweight siblings, 38 siblings with overweight/obesity) who completed ecological momentary assessment (EMA) with accelerometer-assessed physical activity. RESULTS: Generalized linear mixed models indicated z-BMI moderated trait-level and momentary associations. When adolescents with higher z-BMI reported momentary negative affect, they evidenced less MVPA within the next hour. Across the sample, greater overall activity was associated with lower negative affect. However, at the momentary level, when adolescents with higher (but not lower) z-BMI evidenced greater activity, they reported decreases in negative affect. CONCLUSIONS: Findings indicate affective experiences surrounding physical activity differ according to z-BMI. Specifically, momentary negative affect may impede momentary MVPA among youth with higher z-BMI. Further research is warranted to elucidate factors influencing these momentary associations and the extent to which these momentary associations prospectively predict weight change.

Weight discordant siblings' ability to reduce energy intake at a meal as compensation for prior energy intake from sugar-sweetened beverages (SSBs).

BACKGROUND: Insufficient compensation for energy from sugar-sweetened beverages (SSBs) consumed prior to meals may promote greater overall energy intake. If so, ability to compensate for prior energy intake may account for difference in adiposity between adolescents with and without overweight. Studies of fraternal siblings discordant for weight status control for some genetic and shared within-family factors, which allows for testing how putative non-shared factors, such as parental control of feeding, predicts sibling weight differences. AIM: To determine whether same-sex weight-discordant (one with, one without overweight) adolescent siblings differ in ability to compensate for prior energy intake. METHODS: Same-sex biological sibling pairs (mean age = 15.4; 95% confidence interval (CI) 15.1, 15.7) (n = 38 pairs; 21 male pairs) consumed a sugar-sweetened (450 kcal) or a non-nutritive-sweetened (10 kcal) liquid preload of equal volumes on separate days, followed by an ad libitum lunch. Multilevel models examined ability to compensate, dietary restraint, and parental control of child's feeding. RESULTS: Siblings showed insufficient compensation and overate (with overweight = 44 kcal; without overweight = 32 kcal). Siblings shared little within-family similarity in compensation (intra-class correlation coefficient (ICC) = 0.20). Compensation was predicted by parental restriction and general restriction (p = 0.02) Differences in siblings' BMI z-scores were associated with differences in dietary restraint (p = 0.04) not with differences in compensation. CONCLUSION: Sibling differences in compensation for energy from sweetened beverages were not associated with differences in their adiposity. Compensation may be determined by a constellation of factors, including age, parental feeding practices, and food characteristics.

Food reinforcement and delay discounting in zBMI-discordant siblings.

OBJECTIVE: The interaction of food reinforcement and the inability to delay gratification are related to adult energy intake and obesity. This study was designed to test the association of sibling pair differences in relative reinforcing efficacy of food and delay discounting on sibling pair differences in zBMI scores of same-gender zBMI-discordant siblings. DESIGN AND METHODS: We tested main and interactive relationships between delay discounting and relative reinforcing efficacy of food on zBMI discordance in 14 zBMI-discordant biological sibling pairs (6 female pairs) using a discordant sibling study design. RESULTS: Sibling pair differences in relative reinforcing efficacy of food were associated with sibling pair differences in zBMI (p= 0.046); this effect was moderated by delay discounting (p <0.002). Sibling pairs with greater differences in relative reinforcing efficacy and delay discounting had greater differences in zBMI. CONCLUSIONS: The combination of greater sibling pair differences in delay discounting and relative reinforcing efficacy is associated with greater discordance in zBMI in adolescent sibling pairs.

Stress, behavior, and biology: risk factors for cardiovascular diseases in youth.

Psychological stress reactivity is associated with atherogenesis in youth. The novel hypothesis is that stress promotes atherogenic behaviors, including snacking on energy-dense food and reducing physical activity, and increases adiposity. Stress also increases systolic blood pressure cardiovascular reactivity, which also may be atherogenic. Exercise dampens stress reactivity and may be one mechanism by which it protects against the development of cardiovascular diseases.

Food reinforcement and parental obesity predict future weight gain in non-obese adolescents.

BACKGROUND: Food reinforcement, the extent to which people are willing to work to earn a preferred snack food, and parental obesity are risk factors for weight gain, but there is no research comparing the predictive effects of these factors for adolescent weight gain. METHODS: 130 non-obese adolescents (M age=15.2 ± 1.0; M BMI=20.7 ± 2.0; M zBMI=0.16 ± 0.64) at differential risk for weight gain based on parental obesity completed baseline food and money reinforcement tasks, and provided zBMI data over a 2-year follow-up. RESULTS: The number of obese (BMI ≥ 30) parents (p=0.007) and high food reinforcement (p=0.046) were both significant independent predictors of greater zBMI increases, controlling for age, sex, parent education and minority status. Having no obese parents or being low or average in food reinforcement was associated with reductions in zBMI, but those high in food reinforcement showed larger zBMI increases (0.102) than having one obese parent (0.025) but less than having two obese parents (0.177). DISCUSSION: Food reinforcement and parental obesity independently predict future weight gain among adolescents. It might be fruitful for obesity prevention programs to target both high risk groups.

Autonomy supportive environments and mastery as basic factors to motivate physical activity in children: a controlled laboratory study.

BACKGROUND: Choice promotes the experience of autonomy, which enhances intrinsic motivation. Providing a greater choice of traditional active toys may increase children's activity time. Mastery also increases intrinsic motivation and is designed into exergames, which may increase play time of a single exergame, reducing the need for choice to motivate activity compared to traditional active toys. Providing both choice and mastery could be most efficacious at increasing activity time. The energy expenditure (EE) of an active play session is dependent on the duration of play and the rate of EE during play. The rate of EE of exergames and the same game played in traditional fashion is not known. The purpose was to test the basic parameters of choice and mastery on children's physical activity time, activity intensity, and energy expenditure. METHODS: 44 children were assigned to low (1 toy) or high (3 toys) choice groups. Children completed 60 min sessions with access to traditional active toys on one visit and exergame versions of the same active toys on another visit. RESULTS: Choice had a greater effect on increasing girls' (146%) than boys' (23%) activity time and on girls' (230%) than boys' (minus 24%) activity intensity. When provided choice, girls' activity time and intensity were no longer lower than boys' activity time and intensity. The combination of choice and mastery by providing access to 3 exergames produced greater increases in physical activity time (1 toy 22.5 min, 3 toys 41.4 min) than choice alone via access to 3 traditional games (1 toy 13.6 min, 3 toys 19.5 min). Energy expenditure was 83% greater when engaging in traditional games than exergames. CONCLUSIONS: Boys and girls differ in their behavioral responses to autonomy supportive environments. By providing girls with greater autonomy they can be motivated to engage in physical activity equal to boys. An environment that provides both autonomy and mastery is most efficacious at increasing physical activity time. Though children play exergames 87% longer than traditional games, the rate of energy expenditure is 83% lower for exergames than traditional indoor versions of the same games.

Associations between objective physical activity and emotional eating among adiposity-discordant siblings using ecological momentary assessment and accelerometers.

BACKGROUND: Emotional eating is associated with obesity, though less is known regarding factors that predict emotional eating episodes in children and adolescents. OBJECTIVES: To investigate whether moderate to vigorous physical activity (MVPA) or total activity counts 60 minutes prior to psychological stress predicted stress-related eating and positive emotional eating (ie, eating while happy), and whether adiposity (z-BMI) moderated these associations. METHODS: Participants were drawn from a prior study of siblings (N = 77; mean age = 15.4 ± 1.4 years) discordant for weight status (39 non-overweight siblings, 38 siblings with overweight/obesity) who completed an ecological momentary assessment protocol with accelerometer-based assessment of physical activity. RESULTS: Greater MVPA was associated with lower stress-related eating across the sample. Lower total activity (between-person effects) and lower MVPA (within-person effects) were associated with greater stress-related eating for siblings with greater z-BMI. Greater total activity was associated with lower positive emotional eating for siblings with lower z-BMI (between- and within-person). CONCLUSIONS: Findings demonstrate potential regulating effects of prior physical activity on emotional eating at the individual and momentary level, though there are nuances depending on z-BMI. Future work is needed to examine underlying mechanisms and timescale of effects, and particularly the extent to which enhancing MVPA time among youth with z-BMI may mitigate momentary risk of stress-related eating episodes.

Eating Responses to External Food Cues in Weight Discordant Siblings.

PURPOSE: Heightened responsivity to external food cues may promote energy intake and account for differences in weight status between nonoverweight and overweight adolescents. Studies of weight-discordant fraternal siblings control for some genetic and shared within-family factors, which allow for testing of other nonshared factors relevant to sibling weight differences.The aim of the study was to determine whether same-sex weight-discordant (one nonoverweight and one overweight) adolescent siblings differ in responsiveness to external food cues. METHODS: Weight-discordant siblings' (n = 38 pairs) energy consumption was compared following both an appetizing food (pizza) on one day and a control activity (reading) on another day. Multilevel models examined intrafamily similarity, and regressions examined associations with adiposity. RESULTS: Siblings shared little similarity in cue responsivity (ρ = .10). However, sibling body mass index z-scores difference was not associated with differences in cue responsivity. Moreover, when tested as groups, nonoverweight and overweight siblings did not differ for cue responsivity (p > .84). CONCLUSION: Weight-discordant adolescent siblings show little similarity in responses to food cues. Differences in sibling weight status were not predicted by differences in responses to food cues. Thus, nonshared factors other than cue responsivity must contribute to weight differences of adolescent siblings.

The social context moderates the relationship between neighborhood safety and adolescents' activities.

Studies of neighborhood safety and physical activity have typically neglected to consider the youth's peer context as a modifier of these relationships. This study fills this gap in testing the independent and interactive effects of perceived neighborhood safety and time spent with friends and peers on young adolescents' physical activity and sedentary behavior. Participants (N = 80; ages 13-17) completed the Pedestrian/Traffic Safety and Crime Safety subscales of the adolescent version of the Neighborhood Environment Walkability Scale (NEWS). An experience sampling methodology was used to assess sedentary behaviors/screen time and the social context in which physical activity and sedentary time/behavior occurred. Physical activity was assessed via accelerometry. Multilevel models were used to estimate the relationships between predictors (neighborhood safety and social context) and outcomes (physical activity and sedentary time/behavior). Frequency of peer/friend interactions moderated the relationships between neighborhood safety and adolescents' physical activity and sedentary behavior. Specifically, physical activity was more strongly influenced by neighborhood safety among adolescents who reported spending less time with peers and friends than among those who reported frequent peer interactions. Among youths who perceived that their neighborhoods were safer, spending more time with friends and peers was related to greater engagement in sedentary activities, whereas this was not the case among adolescents who perceived that their neighborhoods were less safe. The peer social context moderates the relationship between perceived neighborhood safety and adolescents' physical activity and sedentary behavior. Improving social interactions at the individual level within neighborhoods may decrease concerns of safety.

Effect of Interpersonal and Cognitive Stressors on Habituation and the Utility of Heart Rate Variability to Measure Habituation.

Habituation is a decrease in responding to a repeated stimulus. Operant responding and salivation measure habituation in eating behaviour research. Stress may increase eating by acting as a distractor, yielding spontaneous recovery and prolonging responding for food. Our research tested differences in the ability of cognitive and interpersonal stressors to recover responding for food. We also tested heart rate variability (HRV) as a measure of habituation. Twenty women worked for portions of macaroni and cheese for 15 trials on three separate laboratory visits. Between the 12th and 13th trial, one of three different stressor types (speech, stroop and subtraction) was presented during each visit. HRV was measured continuously throughout the laboratory visits. Responding for food declined across the 12 trials with no difference in rate of habituation by visit (p > 0.8) There was no difference between stressor type in the magnitude of spontaneous recovery after each stressor (p > 0.8). Rates of habituation of HRV variables correlated (p < 0.02) with the rate of operant responding habituation. Cognitive and interpersonal stressors do not differ in their ability to recover reduced responding for food. HRV variables may measure habituation to food similar to operant responding. Copyright © 2014 John Wiley & Sons, Ltd.

Habituation to a stressor predicts adolescents' adiposity.

BACKGROUND AND OBJECTIVES: Stress is associated with gains in adiposity. One factor that determines how much stress is experienced is how quickly an adolescent reduces responding (habituates) across repeated stressors. The purpose of this study was to determine the association of body mass index (BMI) percentile and the rate of habituation to a stressor. DESIGN: Thirty-four adolescents completed anthropometric measures and a habituation protocol using a within study design. METHODS: The habituation protocol measured the rate of decline in perceived stress and heart rate (HR) across four, two-minute serial subtraction trials. RESULTS: Multivariate linear regression revealed the habituation rate of the HR predicted BMI percentile after adjusting for gender, socioeconomic status, and initial HR (ß = 17.2, p < .04). CONCLUSIONS: Slower habituation to a laboratory stressor was associated with greater BMI percentiles in adolescents.

Infant Temperament Is Associated with Relative Food Reinforcement.

OBJECTIVE: Food reinforcement refers to how hard someone is motivated to work to gain access to food. Infant temperament is defined as behavioral styles, or constitutionally based individual differences in reactive and regulatory aspects of behavior. Identifying correlates of food reinforcement, such as infant temperament, may help identify infants at risk for future negative health consequences (e.g., overweight or obesity) of high food reinforcement. METHODS: This study tested aspects of parent-reported negative reactivity and regulation and their associations with relative food reinforcement in a cross-sectional sample of 105 9- to 18-month-old infants. Hierarchical linear regression models were then used to predict infant food reinforcement for the temperament dimensions that were significantly related to it. RESULTS: Two temperament dimensions, cuddliness (regulatory aspect) (B = -0.050, ΔR2 = 0.074, p = 0.005) and rate of recovery from distress and arousal (reactive aspect) (B = -0.040, ΔR2 = 0.045, p = 0.031), were inversely associated with relative food reinforcement. CONCLUSION: Clarifying the nature of relationships between these two behavioral predictors, infant temperament and relative food reinforcement, and early obesity can elucidate the role of individual differences in early obesity risk and can further inform targets for early behavioral obesity preventive interventions.

Reducing relative food reinforcement in infants by an enriched music experience.

OBJECTIVE: The reinforcing value of food may be established early in life. Research shows that infant weight status is related to the relative reinforcing value of food versus non-food alternatives (food reinforcing ratio, FRR). The purpose of this pilot study was to assess the effects of a 6-week music enhancement program (Music Together®, n = 14) versus an active play date control group (n = 13) on the FRR in 9- to 16-month-old infants who were high in relative food reinforcement. METHODS: Participating parents and infants attended six weekly 45-min group classes. Parents in the music group and the play date group were encouraged to listen to the Music Together program CD or play with the play date group's toy with their infants at home, respectively. RESULTS: Intent-to-treat analysis showed a decrease in FRR for infants in the music group (mean ± SD: -0.13 ± 0.13) in comparison to a slight increase in the control group (0.04 ± 0.11) (F[1, 24] = 11.86, P = 0.002). CONCLUSIONS: These findings provide evidence that relative reinforcing value of food can be reduced by promoting alternative reinforcers at an early age.

The Effect of Increasing Autonomy Through Choice on Young Children's Physical Activity Behavior.

BACKGROUND: Increasing autonomy by manipulating the choice of available physical activity options in a laboratory setting can increase physical activity in older children and adults. However, the effect of manipulating the number of physically active choices has yet to be examined in young children in a gymnasium environment. METHODS: Twenty children (n = 10 girls, 6.1 ± 1.4 years old) individually participated in 2 [low choice (LC), high choice (HC)] free-choice activity conditions for 30 minutes in a 4360 square foot gymnasium. Children had access to 2 or 8 physical activity options in the LC and HC conditions, respectively. Physical activity behavior was measured via accelerometry. RESULTS: Children's 30-minute accelerometer counts increased (P < .03) from the LC (2675 ± 294 counts·min-1) to the HC (3224 ± 280 counts·min-1) condition. CONCLUSIONS: Providing greater autonomy through choice of a greater number of physically active options increased young children's physical activity participation by 20.5%.

Origins of food reinforcement in infants.

BACKGROUND: Rapid weight gain in infancy is associated with a higher risk of obesity in children and adults. A high relative reinforcing value of food is cross-sectionally related to obesity; lean children find nonfood alternatives more reinforcing than do overweight/obese children. However, to our knowledge, there is no research on how and when food reinforcement develops. OBJECTIVE: This study was designed to assess whether the reinforcing value of food and nonfood alternatives could be tested in 9- to 18-mo-old infants and whether the reinforcing value of food and nonfood alternatives is differentially related to infant weight status. DESIGN: Reinforcing values were assessed by using absolute progressive ratio schedules of reinforcement, with presentation of food and nonfood alternatives counterbalanced in 2 separate studies. Two nonfood reinforcers [Baby Einstein-Baby MacDonald shows (study 1, n = 27) or bubbles (study 2, n = 30)] were tested against the baby's favorite food. Food reinforcing ratio (FRR) was quantified by measuring the reinforcing value of food (Food Pmax) in proportion to the total reinforcing value of food and a nonfood alternative (DVD Pmax or BUB Pmax). RESULTS: Greater weight-for-length z score was associated with a greater FRR of a favorite food in study 1 (FRR-DVD) (r = 0.60, P < 0.001) and FRR of a favorite food in study 2 (FRR-BUB) (r = 0.49, P = 0.006), primarily because of the strong association between greater weight-for-length z score and lower DVD Pmax (r = -0.71, P < 0.0001) and BUB Pmax (r = -0.53, P = 0.003). Infant monthly weight gain was positively associated with FRR-DVD (r = 0.57, P = 0.009) and FRR-BUB (r = 0.37, P = 0.047). CONCLUSIONS: Our newly developed paradigm, which tested 2 different nonfood alternatives, demonstrated that lean infants find nonfood alternatives more reinforcing than do overweight/obese infants. This observation suggests that strengthening the alternative reinforcers may have a protective effect against childhood obesity.

Case-control study of student-perpetrated physical violence against educators.

PURPOSE: Although prior research focused primarily on student-on-student school violence, educators are also at risk. This study was designed to identify risk factors for assaults against educators. METHODS: Kindergarten-grade 12 educators (n = 26,000), randomly selected from a state license database, were screened for eligibility (6,469, eligible) by mailed questionnaire. Phase 1 (12-month recall) identified eligible assault cases (n = 372) and controls (n = 1,116), June 2004 to December 2005; phase 2 (case-control study; response, 78%) enabled identification of exposures through 1-month recall before student-perpetrated assaults (cases) and randomly selected months (controls). Directed acyclic graphs enabled confounder selection for multivariable logistic regression analyses; reweighting adjusted for potential biases. RESULTS: Risks (odds ratios, 95% confidence intervals) increased for working in: Special Education (5.84; 4.07-8.39) and School Social Work (7.18; 2.72-18.91); kindergarten to second grade (1.81; 1.18-2.77); urban (1.95; 1.38-2.76) schools; schools with less than 50 (8.40; 3.12-22.63), 50-200 (3.67; 1.84-7.34), 201-500 (2.09; 1.32-3.29), and 501-1000 (1.94; 1.25-3.01) students versus more than 1000; schools with inadequate resources always/frequently (1.62; 1.05-2.48) versus infrequently/never; inadequate building safety always/frequently (4.48; 2.54-7.90) versus infrequently/never; and environments with physical barriers (1.50; 1.07-2.10). Risks decreased with routine locker searches (0.49; 0.29-0.85) and accessible exits (0.36; 0.17-0.74). CONCLUSIONS: Identification of assault risk factors provides a basis for further investigation and interventions.

Effect of increasing the choice of active options on children's physically active play.

OBJECTIVES: To determine whether increasing the choice of physical activity options increases the duration and intensity of children's physically active play. DESIGN: This cross-sectional laboratory study included gender (male and female) and choice group [single toy (no choice), three toys (low choice), five toys (high choice)] as between participant factors. METHODS: Boys and girls (n=36, 8-12 y) were stratified, randomly assigned to a choice group that always provided access to each participant's most liked active toy(s), and allowed 60 min of free time. The same sedentary alternatives were freely available to all participants. Physical activity outcomes were measured by accelerometry, heart rate, and direct observation. RESULTS: The number of active toys the children played with increased (p<0.001) across each choice group. Minutes spent in MPA were greater in the low choice (p<0.05) and high choice (p<0.02) groups than the no choice group. Active playtime was greater (p<0.01) in the low choice (79%) and high choice (95%) groups compared to the no choice group. Girls in the low and high choice groups had greater (p<0.05) percent heart rate reserve when compared to girls in the no choice group. There was no difference in the boys' percent heart rate reserve between the no choice, low choice and high choice groups. CONCLUSIONS: Increasing the choice of active toys increases both the duration and intensity of physically active play, especially in girls.

Risk of physical assault against school educators with histories of occupational and other violence: a case-control study.

A case-control study design was used to investigate risks of work-related physical assault (PA) associated with a history of violent victimization among educators. A total of 6,469 state-licensed educators (Kindergarten - Grade 12) worked in the previous 12~months and were eligible to participate. Exposure data were collected from cases (reporting a PA event in previous 12 months, n=290) for the month before PA, and from controls (no work-related PA in previous 12 months; n=867) for a randomly selected working month. Odds ratios and 95% confidence intervals identified increased risks for educators with any prior history of work-related (17.3, 11.4-26.3) or non-work-related PA (2.0, 1.2-3.5). In addition, PA risk in the previous twelve months increased with the number of previous victimizations, and risk also increased for educators with histories of non-physical violence (work- and non work-related). The results present a compelling case for targeted interventions and further research.

Stress-induced cardiovascular reactivity and atherogenesis in adolescents.

OBJECTIVE: To examine the association between cardiovascular reactivity to a set of psychological stressors and carotid artery intima-media thickness, a marker of subclinical cardiovascular disease in healthy adolescents. METHODS: Participants were 25 boys and 23 girls age 14.2 ± 0.9 years who were measured for heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure reactivity to mirror-tracing, reaction time, speech preparation and ad lib speech tasks and for common carotid artery intima-media thickness. Sequential regression analyses were used to establish the incremental increase in R(2)(R(inc)(2)) for the prediction of intima-media thickness due to cardiovascular reactivity independent of age, BMI percentile, sex, socioeconomic status, and resting HR or BP. RESULTS: SBP reactivity while preparing (ß=0.0019, R(inc)(2)=0.09) and giving the speech (ß=0.0014, R(inc)(2)=0.10) and an aggregate reactivity score based on all 4 tasks (ß=0.0026, R(inc)(2)=0.11) independently predicted (p ≤ 0.05) mean carotid artery intima-media thickness. Neither DBP reactivity nor HR reactivity during any task were independent predictors of intima-media thickness. CONCLUSION: Stress-induced cardiovascular reactivity, and especially SBP reactivity, is associated with carotid intima-media thickness and the early pathogenesis of cardiovascular disease. The use of an aggregate stress reactivity index provides a more reliable reflection of trait SBP reactivity to psychological stress and increases the confidence that youth with greater cardiovascular stress reactivity may indeed have greater progression of subclinical cardiovascular disease.