Effect of the Smart Moms intervention on targeted mediators of change in child sugar-sweetened beverage intake.

OBJECTIVE: Few parent-targeted interventions have examined the mechanisms of action by which the intervention changes child behavior. The purpose of this study was to test the theoretical and behavioral mediators of the Smart Moms intervention on changes in child sugar-sweetened beverage and juice (SSB/juice) consumption. STUDY DESIGN: This is a secondary mediation analysis of data from a 6-month randomized controlled trial (N = 51 mother-child dyads) of a mobile phone-based program to reduce child SSB/juice intake compared with a waitlist control group. METHODS: Linear mixed models compared changes in intervention targets from baseline to 3 months between treatment groups. Intervention targets that changed significantly between groups were tested in a multiple mediation model to evaluate their significance as mediators of change in child SSB/juice at 6 months. RESULTS: Maternal beverage consumption but no other behavioral or theoretical intervention targets mediated the effect of the intervention on the reduction in child SSB/juice at 6 months. There were few mediators of the intervention on child SSB/juice change. CONCLUSION: Greater longitudinal research is needed to understand predictors of child dietary changes to inform future intervention efforts. In addition, a greater focus on the measurement of theoretical constructs in family-based child obesity prevention research is needed.

The physical environment in family childcare homes and children's physical activity.

BACKGROUND: Family childcare homes (FCCHs) are the second largest provider of childcare in the United States, yet little is known about how this setting influences children's physical activity, particularly related to the physical environment. Thus, the purpose of this study was to determine what aspects of the FCCH physical environment facilitate or hinder children's physical activity. METHODS: Data were collected from 166 FCCH providers and 496 preschool-aged children in 2013-2014 as part of the Keys to Healthy FCCHs study. Children's moderate-to-vigorous physical activity (MVPA) was measured using Actigraph GT3X+ accelerometers. Wear data from the childcare day were isolated, and cut-points were applied in order to calculate children's minutes of MVPA per hour. FCCH-level estimates of child MVPA per hour were calculated. Indoor and outdoor physical environment characteristics were assessed during a 2-day observation using the Environment and Policy Assessment and Observation modified for FCCHs. General linear models were used to examine the relationship between indoor, portable play equipment, and outdoor FCCH physical environment characteristics and children's MVPA per hour. RESULTS: Only indoor play space was significantly associated with children's MVPA (ß = 0.33; p = .034), indicating that when provided with more indoor space for active play, children were more physically active. No significant associations were noted between portable play equipment or the outdoor environment and children's MVPA. CONCLUSIONS: Indoor space was the only physical environment characteristic associated with children's MVPA, suggesting that teaching FCCH providers how to best utilize their indoor play space for active play may be a way to promote children's physical activity. Futures studies should explore the impact of other environmental characteristics of the FCCH (e.g., provider practices and policies) on children's physical activity.

Preventing childhood obesity in early care and education settings: lessons from two intervention studies.

BACKGROUND: Obesity prevention in young children is a public health priority. In the USA, nearly 10% of children less than 5 years of age are obese, and most attend some form of out-of-home child care. While a number of interventions have been conducted in early care and education settings, few have targeted the youngest children in care or the less formal types of child care like family child care homes. Additionally, only two previous studies provided recommendations to help inform future interventions. METHODS: This paper presents lessons learned from two distinct intervention studies in early care and education settings to help guide researchers and public health professionals interested in implementing and evaluating similar interventions. We highlight two studies: one targeting children ages 4 to 24 months in child care centres and the other intervening in children 18 months to 4 years in family child care homes. We include lessons from our pilot studies and the ongoing larger trials. RESULTS: To date, our experiences suggest that an intervention should have a firm basis in behaviour change theory; an advisory group should help evaluate intervention materials and plan for delivery; and realistic recruitment goals should recognize economic challenges of the business of child care. A flexible data collection approach and realistic sample size calculations are needed because of high rates of child (and sometimes facility) turnover. An intervention that is relatively easy to implement is more likely to appeal to a wide variety of early care and education providers. CONCLUSIONS: Interventions to prevent obesity in early care and education have the potential to reach large numbers of children. It is important to consider the unique features and similarities of centres and family child care homes and take advantage of lessons learned from current studies in order to develop effective, evidence-based interventions.

Effects of providing personalized feedback of child's obesity risk on mothers' food choices using a virtual reality buffet.

BACKGROUND: Providing personalized genetic-risk feedback of a child's susceptibility to adult-onset health conditions is a topic of considerable debate. Family health history (FHH), specifically parental overweight/obesity status, is a useful assessment for evaluating a child's genetic and environmental risk of becoming obese. It is unclear whether such risk information may influence parents' efforts to reduce their child's risk of obesity. PURPOSE: To evaluate whether telling mothers the magnitude of their child's risk of becoming obese based on personal FHH influenced food choices for their young child from a virtual reality-based buffet restaurant. METHODS: Overweight/obese mothers of a child aged 4-5 years who met eligibility criteria (N=221) were randomly assigned to one of three experimental arms, which emphasized different health information: arm 1, food safety control (Control); arm 2, behavioral-risk information (BRI) alone or arm 3, behavioral-risk information plus personal FHH-based risk assessment (BRI+FHH). Mothers donned a head-mounted display to be immersed in a virtual restaurant buffet, where they selected virtual food and beverages as a lunch for their child. RESULTS: Mothers who were randomized to BRI+FHH filled the index child's plate with an average of 45 fewer calories than those in the Control arm (P<0.05); those in the BRI arm filled the plate with 35 fewer calories than the Control arm, a non-significant difference. Calorie restriction was greatest among mothers in the BRI+FHH arm who received the weaker-risk message (that is, only one overweight parent). CONCLUSIONS: The influence of communicating a child's inherited risk of obesity on mothers' feeding practices may vary by the risk level conveyed. High-risk messages may best be coupled with strategies to increase mother's perceptions that efforts can be undertaken to reduce risk and build requisite behavioral skills to reduce risk.

Assessing sustainability of Lifestyle Education for Activity Program (LEAP).

Sustained intervention effects are needed for positive health impacts in populations; however, few published examples illustrate methods for assessing sustainability in health promotion programs. This paper describes the methods for assessing sustainability of the Lifestyle Education for Activity Program (LEAP). LEAP was a comprehensive school-based intervention that targeted change in instructional practices and the school environment to promote physical activity (PA) in high school girls. Previous reports indicated that significantly more girls in the intervention compared with control schools reported engaging in vigorous PA, and positive long-term effects on vigorous PA also were observed for girls in schools that most fully implemented and maintained the intervention 3 years following the active intervention. In this paper, the seven steps used to assess sustainability in LEAP are presented; these steps provide a model for assessing sustainability in health promotion programs in other settings. Unique features of the LEAP sustainability model include assessing sustainability of changes in instructional practices and the environment, basing assessment on an essential element framework that defined complete and acceptable delivery at the beginning of the project, using multiple data sources to assess sustainability, and assessing implementation longitudinally.

Hypoxia: developments in basic science, physiology and clinical studies.

Airway management is primarily designed to avoid hypoxia, yet hypoxia remains the main ultimate cause of anaesthetic-related death and morbidity. Understanding some of the physiology of hypoxia is therefore essential as part of a 'holistic' approach to airway management. Furthermore, it is strategically important that national specialist societies dedicated to airway management do not only focus upon the technical aspects of airway management, but also embrace some of the relevant scientific questions. There has been a great deal of research into causation of hypoxia and the body's natural protective mechanisms and responses to it. This enables us to think of ways in which we might manipulate the cellular and molecular responses to confer greater protection against hypoxia-induced tissue injury. This article reviews some of those aspects.

The effects of wakefulness state on the temporal characteristics of ventilatory variables in man.

The effects of audiovisual stimulation on the temporal patterns of V(T), T(I), T(E) were studied in 11 healthy subjects. 75 datasets of steady-state breathing each of eight minutes in duration were obtained during low wakefulness (lying still, eyes closed), low wakefulness with calibrated thermal pain stimulation and high wakefulness (playing a computer game). The analysis included removal of trend and mean, interpolation and re-sampling of the data to provide an equi-spaced time basis, test for normal distribution of datasets, power spectral estimation, estimation of the parameters of 1st and 2nd order autocorrelation models and estimation of the same parameters on the residuals following subtraction of the 1st or 2nd order models. All power spectra showed the highest power at the lowest frequencies; correspondingly the 1st order autocorrelation coefficients were significant at the 5% level except for T(E) (p = 0.12). The 2nd order coefficients were non-significant for all series. The 1st order autocorrelation coefficients of the residuals (after subtraction of the 1st order autocorrelation component) were all non-significant. With 1st order autocorrelation coefficients averaging between .12 and .37 the non-random part of the variation explained by the 1st order autocorrelation structure is between 1.4% and 13.7% and independent of stimulation of breathing by thermal or mental stimuli.

A mHealth randomized controlled trial to reduce sugar-sweetened beverage intake in preschool-aged children.

BACKGROUND: Sugar-sweetened beverages and maternal weight are strong drivers of child obesity, but few studies have targeted these risk factors as an obesity prevention strategy in children. OBJECTIVE: The objective of this study was to test the efficacy of a smartphone-delivered intervention to reduce parent-provided sugar-sweetened beverage and juice (SSB/juice) consumption among children ages 3-5 and maternal weight. METHODS: Mothers with overweight or obesity, who had a child ages 3-5 that consumed at least 12 fl. oz./day of SSB/juice (N = 51 dyads) were randomized to the Smart Moms group that received one group session, lessons on a mobile website, and text messages, or to a waitlist control group. Mothers self-monitored their children's beverages in addition to their own beverages, high-calorie foods, and weight. Assessments at baseline, 3, and 6 months included dietary recalls to measure SSB/juice intake and objectively measured maternal weight. RESULTS: Using linear mixed models controlling for baseline values, child age and race, there was a greater reduction in child SSB/juice in Smart Moms compared with control at 6 months (-9.7 oz./day vs. 1.7 oz./day, p < .01). Mothers in Smart Moms lost 2.4 kg at 6 months compared with a 0.9-kg gain in the control group (p < .01). CONCLUSIONS: An intervention delivered using mHealth technologies can target mothers to change child dietary behaviours and improve maternal weight, which suggests a novel approach to family-based obesity prevention.

Social marketing approaches to nutrition and physical activity interventions in early care and education centres: a systematic review.

INTRODUCTION: Social marketing is a promising planning approach for influencing voluntary lifestyle behaviours, but its application to nutrition and physical activity interventions in the early care and education setting remains unknown. METHODS: PubMed, ISI Web of Science, PsycInfo and the Cumulative Index of Nursing and Allied Health were systematically searched to identify interventions targeting nutrition and/or physical activity behaviours of children enrolled in early care centres between 1994 and 2016. Content analysis methods were used to capture information reflecting eight social marketing benchmark criteria. RESULTS: The review included 135 articles representing 77 interventions. Two interventions incorporated all eight benchmark criteria, but the majority included fewer than four. Each intervention included behaviour and methods mix criteria, and more than half identified audience segments. Only one-third of interventions incorporated customer orientation, theory, exchange and insight. Only six interventions addressed competing behaviours. We did not find statistical significance for the effectiveness of interventions on child-level diet, physical activity or anthropometric outcomes based on the number of benchmark criteria used. CONCLUSION: This review highlights opportunities to apply social marketing to obesity prevention interventions in early care centres. Social marketing could be an important strategy for early childhood obesity prevention efforts, and future research investigations into its effects are warranted.

Exaggerated blood pressure response to dynamic exercise and risk of future hypertension.

This study examined the association between an exaggerated blood pressure response to treadmill exercise and the risk of developing hypertension. Subjects were healthy normotensive men (n = 5386) who had a baseline graded maximal exercise test between 1971 and 1982, and completed a mailed follow-up questionnaire. At follow-up in 1986, cases (n = 151) reported physician diagnosed hypertension and controls (n = 201) reported normotension. Those who had developed hypertension at follow-up were more likely to have had an exaggerated blood pressure response to exercise (OR = 2.4, 1.4-4.3). In multiple logistic regression analysis an exaggerated response was significantly associated (OR = 3.0, 1.5-6.1) with future hypertension after controlling for sitting systolic and diastolic blood pressure, weight change from age 21 to follow-up, entry age, family history of hypertension, body mass index, treadmill time, alcohol consumption, and years of follow-up. These results suggest that an exaggerated blood pressure response to exercise is independently associated with increased risk of future hypertension, and therefore, may be an important factor in determining hypertension risk.

Levels of consciousness and ventilatory parameters in young children during sedation with oral midazolam and nitrous oxide.

OBJECTIVE: To determine the ventilatory effects and levels of consciousness achieved during sedation with the combination of oral midazolam and inhaled nitrous oxide. DESIGN: Case series. SETTING: Surgical suite. PATIENTS: Twenty-two consecutive children, aged 1 to 3 years, were seen for elective, ambulatory surgery. INTERVENTIONS: Patients were premedicated with oral midazolam hydrochloride, 0.5 mg/kg, and then breathed 4 concentrations of nitrous oxide (N2O) in oxygen (15%, 30%, 45%, and 60%) for 4 minutes at each concentration prior to induction of general anesthesia. MAIN OUTCOME MEASURES: Levels of consciousness (conscious vs deep sedation) and ventilatory parameters: respiratory rate, end-tidal carbon dioxide tension (PETCO2), and oxyhemoglobin saturation (SPO2). Upper airway obstruction was diagnosed by clinical assessment by an experienced pediatric anesthesiologist (R.S.L.) and respiratory impedance plethysmography. RESULTS: During inhalation of N2O, 12 of the 20 children demonstrated a mild degree of ventilatory depression; PETCO2 values were equal to or greater than 45 mm Hg during at least 2 concentrations of N2O studied. There were no significant changes in SPO2 or PETCO2 with increasing concentrations of N2O (P > .05). Respiratory rates tended to be lower during inhalation of 15% N2O than at higher concentrations (P = .05). No child developed upper airway obstruction or hypoxemia (SPO2 < 92%) at any level of N2O inhalation. Sedation scores were significantly higher at 60% N2O than at all other concentrations of N2O (P < .02) At 15% N2O, 12 children were not clinically sedated, 8 children met the American Academy of Pediatrics definition of conscious sedation, and no child met the definition of deep sedation. At 30% N2O, 10 children were not clinically sedated, 9 met the definition of conscious sedation, and 1 child met the definition of deep sedation. At 45% N2O, 9 children were not clinically sedated, 9 met the definition of conscious sedation, and 2 met the definition of deep sedation. At 60% N2O, 6 children were not clinically sedated, 6 met the definition of conscious sedation, 6 met the definition of deep sedation, and 1 child progressed to a deeper level of sedation in that there was no response to a painful stimulus. One child was withdrawn from the study during inhalation of 45% N2O because of emesis. CONCLUSIONS: The combination of oral midazolam, 0.5 mg/kg, and up to 60% inhaled N2O caused mild ventilatory depression in some children and resulted in a progression from conscious to deep sedation beginning at 30% N2O. When using this particular combination of sedatives, practitioners should monitor each child's mental status continuously and adhere to the appropriate published guidelines for the monitoring and management of such patients.

Effect of dopamine on transient ventilatory response to exercise.

The effect of exogenous dopamine on the development of exercise hyperpnea was studied. Using a bicycle ergometer, five subjects performed repetitive square-wave work-load testing from unloaded pedaling to 80% of each subject's estimated anaerobic threshold. The breath-by-breath ventilation (VE), CO2 production (VCO2), and O2 consumption (VO2) responses were analyzed by curve fitting a first-order exponential model. Comparisons were made between control experiments and experiments with a 3-micrograms X kg-1 X min-1 intravenous infusion of dopamine. Steady-state VE, VCO2 and VO2 were unchanged by the dopamine infusion, both during unloaded pedaling and at the heavier work load. The time constants for the increase in VE (tau VE) and VCO2 (tau CO2) were significantly (P less than 0.05) slowed (tau VE = 56.5 +/- 16.4 s for control, and tau VE = 76.4 +/- 26.6 s for dopamine; tau CO2 = 51.5 +/- 10.6 s for control, and tau CO2 = 64.8 +/- 17.4 s for dopamine) (mean +/- SD), but the time constant for VO2 (tau O2) was not significantly affected (tau O2 = 27.5 +/- 11.7 s for control, and tau O2 = 31.0 +/- 10.1 s for dopamine). We conclude that ablation of carotid body chemosensitivity with dopamine slows the transient ventilatory response to exercise while leaving the steady-state response unaffected.

Dynamics of the ventilatory response to central hypoxia in cats.

The dynamics of the effect of central hypoxia on ventilation were investigated by the technique of artificial perfusion of the brain stem in alpha-chloralose-urethan-anesthetized cats. A two-channel roller pump and a four-way valve allowed switching the gas exchanger into and out of the extracorporeal circuit which controlled the brain stem perfusion. When isocapnic hypoxia (arterial PO2 range 18-59 Torr) was limited to the brain stem, a decline in ventilation was consistently found. In 12 cats 47 steps into and 48 steps out of central hypoxia were made. The ventilatory response was fitted using least squares with a model that consisted of a latency followed by a single-exponential function. The latencies for the steps into and out of hypoxia were not significantly different (P = 0.14) and were 32.3 +/- 4.0 and 25.1 +/- 3.6 (SE) s, respectively. The time constant for the steps into hypoxia (149.7 +/- 8.5 s) was significantly longer (P = 0.0002) than for the steps out of hypoxia (105.5 +/- 10.1 s). The time constants for the increase and decrease in ventilation after step changes in the central arterial PCO2 found in a previous study (J. Appl. Physiol. 66: 2168-2172, 1989) were not significantly different (P greater than 0.2) from the corresponding time constants in this study (for 7 cats common to both studies). Theories of the mechanisms behind hypoxic ventilatory decline need to account for the long latency, the similarity between the time constants for the ventilatory response to O2 and CO2, and the differences between the time constants for increasing and decreasing ventilation.

Dynamic response of the peripheral chemoreflex loop to changes in end-tidal O2.

We studied the peripheral ventilatory response dynamics to changes in end-tidal O2 tension (PETO2) in 13 cats anesthetized with alpha-chloralose-urethan. The arterial O2 tension in the medulla oblongata was kept constant using the technique of artificial perfusion of the brain stem. At constant end-tidal CO2 tension, 72 ventilatory on-responses due to stepwise changes in PETO2 from hyperoxia (45-55 kPa) to hypoxia (4.7-9.0 kPa) and 62 ventilatory off-responses due to changes from hypoxia to hyperoxia were assessed. We fitted two exponential functions with the same time delay to the breath-by-breath ventilation and found a fast and a slow component in 85% of the ventilatory on-responses and in 76% of the off-responses. The time constant of the fast component of the ventilatory on-response was 1.6 +/- 1.5 (SD) s, and that of the off-response was 2.4 +/- 1.3 s; the gain of the on-response was smaller than that of the off-response (P = 0.020). For the slow component, the time constant of the on-response (72.6 +/- 36.4 s) was larger (P = 0.028) than that of the off-response (43.7 +/- 28.3 s), whereas the gain of the on-response exceeded that of the off-response (P = 0.031). We conclude that the ventilatory response of the peripheral chemoreflex loop to stepwise changes in PETO2 contains a fast and a slow component.

Comparison of chemoreflex gains obtained with two different methods in cats.

This study investigates the correspondence between results of the ventilatory response to CO2 obtained using the technique of dynamic end-tidal CO2 forcing (DEF) and results obtained using the technique of artificial brain stem perfusion (ABP). The DEF technique separates the dynamic ventilatory response into a slow and fast component with gains g1 and g2 as well as the extrapolated CO2 tension at zero ventilation (Bk). The ABP technique results in steady-state central (Sc) and peripheral (Sp) chemoreflex gains and extrapolated CO2 tension at zero ventilation (B). Experiments were performed on 14 alpha-chloralose-urethan anesthetized cats. A wide range of relative peripheral chemosensitivities was obtained by subjecting eight cats to normoxic and three cats to hypoxic CO2 challenges and three cats to both conditions. Statistical analysis of the experimental data showed that the vectors (g1, g2, Bk) and (Sc, Sp, B) for each cat did not differ significantly (P = 0.56). This was also the case for the vectors [g2/(g1 + g2), Bk] and [Sp/(Sc + Sp), B] (P = 0.21). We conclude that in the DEF experiments the slow ventilatory response to isoxic changes in end-tidal CO2 can be equated with the central chemoreflex loop and the faster ventilatory response to the peripheral chemoreflex loop. The agreement between the two techniques is good.

Dynamics of ventilatory response to step changes in PCO2 of blood perfusing the brain stem.

The technique of artificial brain stem perfusion was used to assess the ventilatory response to step changes in PCO2 of the blood perfusing the brain stem of the cat. A two-channel roller pump and a four-way valve allow switching the gas exchanger into and out of the extracorporeal circuit, which controlled the perfusion to the brain stem. Seven alpha-chloralose-urethan-anesthetized cats were studied, and 25 steps of increasing and 23 steps of decreasing PCO2 were analyzed. A model consisting of a single-exponential function with time delay best described the ventilatory response. The time delays 11.7 +/- 8.1 and 6.4 +/- 6.8 (SD) s (obtained from mean values per cat) for the step into and out of hypercapnia, respectively, were not significantly different (P = 0.10) and were of the order of the transit time of the tubing from valve to brain stem. The steady-state CO2 sensitivities obtained from the on- and off-responses were also not significantly different (P = 0.10). The time constants 87 +/- 25 and 150 +/- 51 s, respectively, were significantly different (P = 0.0002). We conclude that the central chemoreflex is adequately modeled by a single component with a different time constant for on- and off-responses.

Dynamic response of peripheral chemoreflex loop to changes in end-tidal CO2.

The dynamic ventilatory response of the peripheral chemoreflex loop after isoxic step changes in end-tidal PCO2 (PETCO2) (range 5-30 Torr) was studied in 12 alpha-chloralose-urethan-anesthetized cats. The technique of artificial brain stem perfusion allowed the response to be observed in isolation from the central chemoreflex loop. The data were fitted by an exponential with time delay. During normoxia the mean time constant and time delay (with SD) were 8.6 +/- 7.3 and 3.3 +/- 0.9 s, respectively (9 cats, 56 runs). During hypoxia [arterial PO2 (PaO2) approximately 60 Torr] these values were 6.0 +/- 4.5 and 2.9 +/- 0.9 s (6 cats, 38 runs). In 17 of the 94 runs an augmented breath occurred in the first three breaths after the stepwise increase in PETCO2. For these augmented breaths, tidal volume, inspiratory time, and expiratory time were not different from the next augmented breath occurring in the same run in the steady state. Neither a rate-sensitive component nor a central neural mechanism (central afterdischarge), with the property of maintaining an increased but slowly declining respiratory activity for some minutes after cessation of the PETCO2 challenge, was found. We conclude that the description of the ventilatory response of the peripheral chemoreflex loop to step changes in PETCO2 with a single exponential and time delay is adequate.

Correlates of objectively measured physical activity in preadolescent youth.

OBJECTIVE: The purpose of this study was to identify the psychosocial and environmental correlates of objectively measured physical activity behavior in a diverse sample of sixth-grade students. DESIGN: Cross-sectional. PARTICIPANTS AND SETTINGS: One hundred ninety-eight sixth-grade students from 4 public middle schools in Columbia, South Carolina. The study group was 52.0% female, 55.1% African-American, with a mean age of 11.4 +/- 0.6 years. MAIN OUTCOME MEASURES: Time spent in moderate physical activity (MPA) and vigorous physical activity (VPA) was assessed using a uniaxial accelerometer (CSA WAM 7164) (Computer Science and Applications Inc., Shalimar, FL). Determinant variables included: age, gender, race/ethnicity (demographic); physical activity self-efficacy, social norms related to physical activity, and beliefs regarding physical activity outcomes (psychosocial); and perceived physical activity habits of parents and peers, involvement in community physical activity organizations, involvement in community-based sports programs, access to fitness/sporting equipment at home, and self-reported hours spent watching television or playing video games (environmental). RESULTS: For boys, physical activity self-efficacy, social norms related to physical activity, and involvement in community physical activity organizations were salient predictors of MPA and VPA. Among girls, only physical activity self-efficacy emerged as a clear predictor of objectively measured physical activity. CONCLUSIONS: These findings are consistent with previous studies using self-reported physical activity and suggest that interventions to increase physical activity in preadolescent youth should endeavor to boost physical activity self-efficacy by offering a wide selection of enjoyable, developmentally-appropriate physical activity options.