Understanding Accelerated Summer Body Mass Index Gain by Tracking Changes in Children's Height, Weight, and Body Mass Index Throughout the Year

Background: Drivers of summer body mass index (BMI) gain in children remain unclear. The Circadian and Circannual Rhythm Model (CCRM) posits summer BMI gain is biologically driven, while the Structured Days Hypothesis (SDH) proposes it is driven by reduced structure. Objectives: Identify the mechanisms driving children's seasonal BMI gain through the CCRM and SDH. Methods: Children's (N = 147, mean age = 8.2 years) height and weight were measured monthly during the school year, and once in summer (July-August). BMI z-score (zBMI) was calculated using CDC growth charts. Behaviors were measured once per season. Mixed methods regression estimated monthly percent change in children's height (%HΔ), weight (%WΔ), and monthly zBMI for school year vs. summer vacation, seasonally, and during school months with no breaks vs. school months with a break ≥1 week. Results: School year vs. summer vacation analyses showed accelerations in children's %WΔ (Δ = 0.9, Standard Error (SE) = 0.1 vs. Δ = 1.4, SE = 0.1) and zBMI (Δ = -0.01, SE = 0.01 vs. Δ = 0.04, SE = 0.3) during summer vacation, but %HΔ remained relatively constant during summer vacation compared with school (Δ = 0.3, SE = 0.0 vs. Δ = 0.4, SE = 0.1). Seasonal analyses showed summer had the greatest %WΔ (Δ = 1.8, SE = 0.4) and zBMI change (Δ = 0.05, SE = 0.03) while %HΔ was relatively constant across seasons. Compared with school months without a break, months with a break showed higher %WΔ (Δ = 0.7, SE = 0.1 vs. Δ = 1.6, SE = 0.2) and zBMI change (Δ = -0.03, SE = 0.01 vs. Δ = 0.04, SE = 0.01), but %HΔ was constant (Δ = 0.4, SE = 0.0 vs. Δ = 0.3, SE = 0.1). Fluctuations in sleep timing and screen time may explain these changes. Conclusions: Evidence for both the CCRM and SDH was identified but the SDH may more fully explain BMI gain. Interventions targeting consistent sleep and reduced screen time during breaks from school may be warranted no matter the season.

Diet Quality among Pre-Adolescent African American Girls in a Randomized Controlled Obesity Prevention Intervention Trial

Consuming an unhealthy diet increases health risks. This study assessed the impact of a culturally adapted behaviorally innovative obesity prevention intervention (The Butterfly Girls and the Quest for Founder's Rock) on diet quality in pre-adolescent non-Hispanic Black/African American girls. The RCT consisted of three groups (experimental, comparison, and waitlist control); block randomization allocated participants to each group. The two treatment groups varied in terms of whether or not they set goals. Data were collected at baseline (prior to receiving the intervention), post 1 (3 months post-baseline), and post 2 (6 months post-baseline). Two dietitian-assisted 24 h dietary recalls were collected at each timepoint. Healthy Eating Index 2015 (HEI-2015) was used to determine diet quality. A total of 361 families were recruited; 342 completed baseline data collection. No significant differences in overall HEI score or component scores were observed. To attain more equitable health outcomes, future efforts to promote dietary intake change among at-risk children should explore other behavior change procedures and employ more child-friendly dietary assessment methods.

Examination of parent-reported differences in children's daily screen use, sleep, and sleep hygiene behaviors during the school year and summer and their association with BMI

OBJECTIVE

The current study examined school-summer differences in children's sleep patterns and sleep hygiene. Cross-sectional relationships with children's sleep, sleep hygiene, and weight status were explored during the school year and summer.

METHODS

Children (5-8 years) and their parents (n = 197 dyads) were recruited from 4 schools in southeastern Texas and via Facebook. Parents reported children's school year and summer sleep, sleep hygiene, and screen media use. Children's body mass index (BMI) was objectively assessed at the beginning and end of the summer. Associations between children's sleep hygiene and screen media use, sleep duration, and weight status were explored.

RESULTS

Children's sleep midpoint was earlier during the school year (1:54 AM ± 0.03) than in the summer (2:06 AM ± 0.03; t = 4.07, p < .0001). During summer, children increased their screen media use by 38 minutes (t = 2.32, p = .023) and decreased their caffeine intake from 7.43 to 7.0 (with scores ranging from 3 to 15; t = 2.83, p = .006). Greater sleep-inhibiting (β = 0.40, p = .011) and fewer sleep-promoting (β = -0.28, p = .049) behaviors during the school year were associated with having a higher BMI. There were no associations among sleep patterns, sleep hygiene and BMI during summer.

CONCLUSIONS

More positive school year sleep hygiene behaviors were supportive of having a healthier weight status. Changes in these behaviors during the summer did not portend worse weight outcomes. Supporting families in the establishment of sleep-promoting behaviors, particularly during the school year may help address the child obesity epidemic.

Validation of the Entrainment Signal Regularity Index and associations with children's changes in BMI

OBJECTIVE

This study examined the validity of a novel metric of circadian health, the Entrainment Signal Regularity Index (ESRI), and its relationship to changes in BMI during the school year and summer.

METHODS

In a longitudinal observational data set, this study examined the relationship between ESRI score and children's (n = 119, 5- to 8-year-olds) sleep and physical activity levels during the school year and summer, differences in ESRI score during the school year and summer, and the association of ESRI score during the school year and summer with changes in BMI across those time periods.

RESULTS

The ESRI score was higher during the school year (0.70 ± 0.10) compared with summer (0.63 ± 0.11); t(111) = 5.484, p < 0.001. Whereas the ESRI score at the beginning of the school year did not significantly predict BMI change during the school year (β = 0.05 ± 0.09 SE, p = 0.57), having a higher ESRI score during summer predicted smaller increases in BMI during summer (β = -0.22 ± 0.10 SE, p = 0.03).

CONCLUSIONS

Overall, children demonstrated higher entrainment regularity during the school year compared with the summer. During summer, having a higher entrainment signal was associated with smaller changes in summertime BMI. This effect was independent of the effects of children's sleep midpoint, sleep regularity, and physical activity on children's BMI.

The Role of Sleep and Eating Patterns in Adiposity Gain among Preschool-Aged Children

BACKGROUND

Short sleep duration is related to risk for obesity in preschool children. However, the underlying mechanism(s) are not clear.

OBJECTIVE

We evaluated the relationship between sleep characteristics with body composition, energetics and weight-regulating behaviors in preschool-aged children; and the longitudinal associations between children's sleep and eating patterns with body composition at 1-year follow-up.

METHODS

Data were drawn from a longitudinal study of 118 children aged 3-5 years. Sleep (duration, midpoint, regularity) and physical activity (PA) were measured by accelerometry over 6 consecutive days; total energy expenditure (TEE) using the doubly-labeled water method; body composition (fat mass, fat-free mass, and %body fat) by dual energy x-ray absorptiometry; and dietary intake (energy intake, timing) using two 24-h recalls. Multivariable regression was used to estimate interindividual associations of sleep parameters with body composition, PA, TEE and dietary outcomes; and to examine the relationship between sleep and dietary behaviors with body composition one year later.

RESULTS

Cross-sectionally, later sleep midpoint was associated with greater fat mass (0.33; 95% CI: 0.05, 0.60) and %body fat (0.92; 95% CI: 0.15, 1.70). Later sleep midpoint was associated with delayed morning (0.51; 95% CI: 0.28, 0.74) and evening meal times (0.41; 95% CI: 0.29, 0.53), higher nighttime (45.6; 95% CI: 19.7, 71.4), and lower morning (-44.8; 95% CI: -72.0, -17.6) energy intake. Longitudinally, shorter sleep duration (-0.02; 95% CI: -0.03, -0.00) and later meal timing (0.83; 95% CI: 0.24, 1.42) were associated with higher %body fat 1 year later.

CONCLUSIONS

Shorter sleep duration and later meal timing are associated with adiposity gain in preschoolers.

Estimating circadian phase in elementary school children: leveraging advances in physiologically informed models of circadian entrainment and wearable devices

STUDY OBJECTIVES

Examine the ability of a physiologically based mathematical model of human circadian rhythms to predict circadian phase, as measured by salivary dim light melatonin onset (DLMO), in children compared to other proxy measurements of circadian phase (bedtime, sleep midpoint, and wake time).

METHODS

As part of an ongoing clinical trial, a sample of 29 elementary school children (mean age: 7.4 ± .97 years) completed 7 days of wrist actigraphy before a lab visit to assess DLMO. Hourly salivary melatonin samples were collected under dim light conditions (<5 lx). Data from actigraphy were used to generate predictions of circadian phase using both a physiologically based circadian limit cycle oscillator mathematical model (Hannay model), and published regression equations that utilize average sleep onset, midpoint, and offset to predict DLMO. Agreement of proxy predictions with measured DLMO were assessed and compared.

RESULTS

DLMO predictions using the Hannay model outperformed DLMO predictions based on children's sleep/wake parameters with a Lin's Concordance Correlation Coefficient (LinCCC) of 0.79 compared to 0.41-0.59 for sleep/wake parameters. The mean absolute error was 31 min for the Hannay model compared to 35-38 min for the sleep/wake variables.

CONCLUSION

Our findings suggest that sleep/wake behaviors were weak proxies of DLMO phase in children, but mathematical models using data collected from wearable data can be used to improve the accuracy of those predictions. Additional research is needed to better adapt these adult models for use in children.

CLINICAL TRIAL

The i Heart Rhythm Project: Healthy Sleep and Behavioral Rhythms for Obesity Prevention https://clinicaltrials.gov/ct2/show/NCT04445740.

Seasonality of Children’s Height and Weight and Their Contribution to Accelerated Summer Weight Gain

Background: While children have been shown to have increased BMI during the summer compared to the school year, it is not known if this may be due to seasonal variations in height or weight separately.

Methods: Trained nurses measured heights (cm) and weights (kg) in a cohort of Kindergarteners (n = 7648) twice per year from the beginning of kindergarten through 5th grade. Variation in height and weight by season (school year vs. summer) was examined using separate mixed-effects models. Season, sex, and BMI trajectory group were tested as fixed effects. Random effects included repeated measurements of time, students nested within a school, intercept, and slope for growth over time. Similar models using BMIz as the outcome examined the interaction of height or weight with season.

Results: The rate of height gain was greater during the school year (∼Sept to April) compared to summer (∼April to Sept) (β = -0.05, SE = 0.013, p < 0.0001). The rate of weight gain did not differ seasonally. Height gain was more strongly associated with increased BMIz during summer compared to the school year (β =.02, SE = 0.005, p <0 .0001), mainly among children who remained healthy weight throughout elementary school (β = 0.014, SE = 0.003, p < 0.0001) and those who transitioned to a healthier weight status (β = 0.026, SE = 0.008, p = 0.004). We found a similar seasonal effect for the association between weight with BMIz among children who maintained a healthy weight status (β = 0.014, SE = 0.014, p < 0.0001).

Conclusion: This study indicates seasonality in children’s height gain, gaining height at a faster rate during the school year compared to the summer, while weight gain remained relatively more consistent throughout the year. Seasonality in height and weight gain had the greatest impact on BMIz among children with a healthy weight status. Future research with more frequent measurements is needed to better understand the seasonal regulation of children’s growth and weight gain.

Evaluation of Circadian Rhythm and Sleep Focused mHealth Intervention for the Prevention of Accelerated Summer Weight Gain among Elementary School-Age Children: Protocol for a Randomized Controlled Feasibility Study (Preprint)

Background

The i♥rhythm project is a mobile health adaptation of interpersonal and social rhythm therapy designed to promote healthy sleep and behavioral rhythms among 5-8-year olds during summer for the prevention of accelerated summer weight gain.

Objective

This pilot study will examine the feasibility, acceptability, and preliminary efficacy of the i♥rhythm intervention. This will ensure that the research protocol and procedures work as desired and are acceptable to families in preparation for the fully powered randomized controlled trial. The proposed study will examine the willingness of participants to participate in the intervention and determine whether modifications to the intervention, procedures, and measures are needed before conducting a fully powered study. We will assess our ability to (1) recruit, consent, and retain participants; (2) deliver the intervention; (3) implement the study and assessment procedures; (4) assess the reliability of the proposed measures; and (5) assess the acceptability of the intervention and assessment protocol.

Methods

This study will employ a single-blinded 2-group randomized control design (treatment and no-treatment control) with randomization occurring after baseline (Time 0) and 3 additional evaluation periods (postintervention [Time 1], and 9 months [Time 2] and 12 months after intervention [Time 3]). A sample of 40 parent-child dyads will be recruited.

Results

This study was approved by the institutional review board of Baylor College of Medicine (H-47369). Recruitment began in March 2021. As of March 2022, data collection and recruitment are ongoing.

Conclusions

This study will address the role of sleep and circadian rhythms in the prevention of accelerated summer weight gain and assess the intervention’s effects on the long-term prevention of child obesity.

Trial Registration

ClinicalTrials.gov NCT04445740; https://clinicaltrials.gov/ct2/show/NCT04445740.

International Registered Report Identifier (IRRID)

DERR1-10.2196/37002

Later sleep timing predicts accelerated summer weight gain among elementary school children: a prospective observational study

OBJECTIVES AND BACKGROUND

Social demands of the school-year and summer environment may affect children's sleep patterns and circadian rhythms during these periods. The current study examined differences in children's sleep and circadian-related behaviors during the school-year and summer and explored the association between sleep and circadian parameters and change in body mass index (BMI) during these time periods.

METHODS

This was a prospective observational study with 119 children ages 5 to 8 years with three sequential BMI assessments: early school-year (fall), late school-year (spring), and beginning of the following school-year in Houston, Texas, USA. Sleep midpoint, sleep duration, variability of sleep midpoint, physical activity, and light exposure were estimated using wrist-worn accelerometry during the school-year (fall) and summer. To examine the effect of sleep parameters, physical activity level, and light exposure on change in BMI, growth curve modeling was conducted controlling for age, race, sex, and chronotype.

RESULTS

Children's sleep midpoint shifted later by an average of 1.5 h during summer compared to the school-year. After controlling for covariates, later sleep midpoints predicted larger increases in BMI during summer, (γ = .0004, p = .03), but not during the school-year. Sleep duration, sleep midpoint variability, physical activity levels, and sedentary behavior were not associated with change in BMI during the school-year or summer. Females tended to increase their BMI at a faster rate during summer compared to males, γ = .06, p = .049. Greater amounts of outdoor light exposure (γ = -.01, p = .02) predicted smaller increases in school-year BMI.

CONCLUSIONS

Obesity prevention interventions may need to target different behaviors depending on whether children are in or out of school. Promotion of outdoor time during the school-year and earlier sleep times during the summer may be effective obesity prevention strategies during these respective times.

Variability of Sleep and Relations to Body Weight Among First-Year College Students

BACKGROUND

Existing research suggests that greater sleep variability may increase risk for weight gain. College often marks a transition to a less consistent daily schedule, which may adversely impact sleep routines and further increase risk for weight gain. The current study is among the first to explore relations between nighttime sleep variability and daytime sleep (napping) and body weight among first-year college students.

METHODS

Using daily diary methods, first-year college students (N = 307; 84.7% female) self-reported their sleep for seven days. Several indices were created to capture sleep variability for reported bedtime, wake time, and sleep duration, including weekday versus weekend differences (WvW), day to day differences (D2D), and overall standard deviation (SD). Napping was also assessed. Based on body mass index (BMI), individuals were categorized as underweight, healthy weight, overweight, and obese.

RESULTS

Across indices, students' sleep varied over an hour on average across the week. Hierarchical regressions revealed that greater differences in wake time D2D, wake time SD, and sleep duration WvW were all associated with higher BMI, after accounting for gender, depressive symptoms, and sleep duration. Longer napping was also associated with higher BMI, using the same covariates. Finally, greater sleep variability was reported by overweight and obese than healthy weight individuals.

CONCLUSION

These findings suggest that sleep variability, particularly wake times and napping may be important modifiable sleep behaviors to investigate in future studies. More longitudinal research is needed to explore relations between multiple facets of sleep variability and weight gain, including possible mechanisms.

Integrating wearable data into circadian models

The emergence of wearable health sensors in the last decade has the potential to revolutionize the study of sleep and circadian rhythms. In particular, recent progress has been made in the use of mathematical models in the prediction of a patient's internal circadian state using data measured by wearable devices. This is a vital step in our ability to identify optimal circadian timing for health interventions. We review the available data for fitting circadian phase models with a focus on wearable data sets. Finally, we review the current modeling paradigms and explore avenues for developing personalized parameter sets in limit cycle oscillator models in order to further improve prediction accuracy.

Physiological mechanisms underlying children's circannual growth patterns and their contributions to the obesity epidemic in elementary school age children

Several studies since the 1990s have demonstrated that children increase their body mass index at a faster rate during summer months compared with the school year, leading some to conclude that the out-of-school summer environment is responsible. Other studies, however, have suggested that seasonality may play a role in children's height and weight changes across the year. This article reviews evidence for seasonal differences in the rate of children's height and weight gain and proposes potential physiological mechanisms that may explain these seasonal variations.

Symptom prevalence differences of depression as measured by BDI and PHQ scales in the Look AHEAD study

OBJECTIVE

To compare depressive symptomatology as assessed by two frequently used measures, the Beck Depression Inventory (BDI-1A) and Patient Health Questionnaire (PHQ-9).

METHODS

Investigators conducted a cross-sectional secondary analysis of data collected as part of the follow-up observational phase of the Look AHEAD study. Rates of agreement between the BDI-1A and PHQ-9 were calculated, and multivariable logistic regression was used to examine the relationship between differing depression category classifications and demographic factors (ie, age, sex, race/ethnicity) or comorbidities (ie, diabetes control, cardiovascular disease).

RESULTS

A high level of agreement (κ = 0.47, 95% CI (0.43 to 0.50)) was found in the level of depressive symptomatology between the BDI-1A and PHQ-9. Differing classifications (minimal, mild, moderate, and severe) occurred in 16.8% of the sample. Higher scores on the somatic subscale of the BDI-1A were significantly associated with disagreement as were having a history of cardiovascular disease, lower health-related quality of life, and minority racial/ethnic classification.

CONCLUSIONS

Either the BDI-1A or PHQ-9 can be used to assess depressive symptomatology in adults with overweight/obesity and type 2 diabetes. However, further assessment should be considered in those with related somatic symptoms, decreased quality of life, and in racial/ethnic minority populations.

Potential circadian and circannual rhythm contributions to the obesity epidemic in elementary school age children

Children gain weight at an accelerated rate during summer, contributing to increases in the prevalence of overweight and obesity in elementary-school children (i.e., approximately 5 to 11 years old in the US). Int J Behav Nutr Phys Act 14:100, 2017 explained these changes with the "Structured Days Hypothesis" suggesting that environmental changes in structure between the school year and the summer months result in behavioral changes that ultimately lead to accelerated weight gain. The present article explores an alternative explanation, the circadian clock, including the effects of circannual changes and social demands (i.e., social timing resulting from societal demands such as school or work schedules), and implications for seasonal patterns of weight gain. We provide a model for understanding the role circadian and circannual rhythms may play in the development of child obesity, a framework for examining the intersection of behavioral and biological causes of obesity, and encouragement for future research into bio-behavioral causes of obesity in children.

Multi-etiological Perspective on Child Obesity Prevention

PURPOSE OF REVIEW

The simple energy balance model of obesity is inconsistent with the available findings on obesity etiology, prevention, and treatment. Yet, the most commonly stated causes of pediatric obesity are predicated on this model. A more comprehensive biological model is needed upon which to base behavioral interventions aimed at obesity prevention. In this light, alternative etiologies are little investigated and thereby poorly understood.

RECENT FINDINGS

Three candidate alternate etiologies are briefly presented: infectobesity, the gut microbiome, and circadian rhythms. Behavioral child obesity preventive investigators need to collaborate with biological colleagues to more intensively analyze the behavioral aspects of these etiologies and to generate innovative procedures for preventing a multi-etiological problem, e.g., group risk analysis, triaging for likely causes of obesity.

School-Based Weight Management Program Curbs Summer Weight Gain Among Low-Income Hispanic Middle School Students

BACKGROUND

Research shows that elementary students gain weight over the summer. It is unknown if these findings apply to Hispanic adolescents. We evaluated school and summer standardized body mass index (zBMI) changes in Hispanic middle school students.

METHODS

Hispanic middle school students were randomly assigned to a weight management program (N = 230) or control condition (N = 195). Paired sample t-tests compared zBMI change scores during the school year versus summer when not enrolled in a weight management program (eg, control group). We used 2 × 2 repeated measures analysis of variances to determine program group differences in zBMI scores across school versus summer periods separately for normal and overweight/obese students.

RESULTS

In the control group, students' zBMI change scores decreased during the school year, but increased during summer for both normal weight and overweight/obese students. Program effects on zBMI indicated school year decreases and summer increases for both normal and overweight/obese students. However, zBMI scores did not differ by program status for normal weight students. Overweight/obese students in the program compared to the control group increased zBMI to a lesser extent over the summer.

CONCLUSION

For all students, zBMI increased during the summer. A school-based weight management program protected overweight/obese students against potentially greater summer weight gain.

Integrating CHWs as Part of the Team Leading Diabetes Group Visits: A Randomized Controlled Feasibility Study

Purpose The purpose of the study was to evaluate the feasibility of integrating Community Health Workers (CHWs) as part of the team leading diabetes group visits. Methods This was a randomized controlled study that integrated CHWs as part of the team leading diabetes group visits for low-income Hispanic adults (n = 50). Group visits met for 3 hours each month for a 6-month duration. Main measures included baseline and 6-month clinical outcomes (ie, A1C, lipids), concordance with 8 standard of care guidelines (ie, screens for cervical, breast, and colon cancer) from the US Preventive Task Force and American Diabetes Association, and participant acceptability. Results Compared to control participants, the intervention group resulted in significantly better clinical outcomes or guideline concordance for the following areas: target A1C levels, retinal eye exams, diabetes foot exams, mammograms, and urine microalbumin. Significantly more individuals in the control group gained weight, whereas a greater number of participants in the intervention group lost weight. Intervention participants found the group visits highly acceptable. Conclusions Integrating CHWs as part a comprehensive diabetes group visit program is a feasible and effective system-level intervention to improve glycemic control and achieve guideline concordance.

Impact of child summertime obesity interventions on body mass index, and weight-related behaviours: a systematic review and meta-analysis protocol

INTRODUCTION

In previous studies, it has been found that on average, children consistently gained weight during the summer months at an increased rate compared with the 9-month school year. This contributed to an increased prevalence of overweight and obesity in children. Several obesity-related interventions have occurred during or targeting the summer months. We propose to conduct a systematic review and meta-analysis of the impact of obesity prevention and treatment interventions for school-age children conducted during the summer or targeting the summer months when children are not in school on their body mass index (BMI), or weight-related behaviours.

METHODS AND ANALYSES

A literature search will be conducted by the first author (JPM) using MEDLINE/PubMed, Cochrane Library, Scopus, CINAHL, PsycINFO, EMBASE and Proquest Dissertations and Theses databases from the date of inception to present. Studies must examine interventions that address the modification or promotion of weight-related behaviours (eg, dietary patterns, eating behaviours, physical activity (PA), sedentary behaviour or sleep) and target school-age children (ages 5-18). The primary outcomes will be changes from baseline to postintervention and/or the last available follow-up measurement in weight, BMI, BMI percentile, standardised BMI or per cent body fat. Secondary outcomes will include changes in dietary intake, PA, sedentary behaviour or sleep. Risk of bias will be assessed using the Cochrane risk of bias tool for randomised and non-randomised studies, as appropriate.

ETHICS AND DISSEMINATION

Because this is a protocol for a systematic review, ethics approval will not be required. The findings will be disseminated via presentations at scientific conferences and published in a peer-reviewed journal. All amendments to the protocol will be documented and dated and reported in the PROSPERO trial registry.

PROSPERO REGISTRATION NUMBER

CRD42016041750.

Compañeros: High School Students Mentor Middle School Students to Address Obesity Among Hispanic Adolescents

INTRODUCTION

Promotoras, Hispanic community health workers, are frequently employed to promote health behavioral change with culturally bound Hispanic lifestyle behaviors. Peer health mentors have been used in schools to promote healthy nutrition and physical activity behaviors among students. This study investigates the efficacy of combining these 2 approaches by training high school health mentors, called compañeros, to engage Hispanic middle school students in a school-based obesity intervention as a strategy to promote and sustain reductions in standardized body mass index (zBMI).

METHODS

High school compañeros were trained to participate in a 6-month obesity program alongside middle school students in Houston, Texas. Middle school students were randomized to participate in the program either with compañeros (n = 94) or without compañeros (n = 95). The intervention was conducted from 2013 through 2016 in 3 cohorts of students, 1 each school year. Students were followed for 12 months. The primary outcome was zBMI, which was analyzed at baseline, 6 months, and 12 months.

RESULTS

Significant differences were found between conditions across time (F = 4.58, P = .01). After the 6-month intervention, students in the condition with compañeros had a larger decrease in zBMI (F = 6.94, P = .01) than students in the condition without compañeros. Furthermore, students who received the intervention with compañeros showed greater sustained results at 12 months (F = 7.65, P = .01).

CONCLUSION

Using high school compañeros in an obesity intervention for Hispanic middle school students could be effective in promoting and maintaining reductions in zBMI.

Individual, social and environmental determinants of sleep among women: protocol for a systematic review and meta-analysis

INTRODUCTION

Sleep is important to promote optimal health and avoid negative health outcomes. Short-duration and low-quality sleep may be more common and more detrimental among women compared with men. Identifying the determinants of behaviour is one of the first steps in designing effective interventions. To our knowledge, no systematic review has identified the individual, social and environmental determinants of sleep among adult women.

METHODS AND ANALYSIS

Studies reporting data on adult women from 18 to 64 years of age will be included. On the basis of ecological models of health behaviour and sleep, the types of determinants that will be included in the review are individual (eg, demographic, psychological and behavioural), social (eg, family) and environmental (eg, physical environment and policies) determinants. Observational (cross-sectional and longitudinal) and experimental studies will be included. MEDLINE/PubMed, PsycINFO, CINAHL, EMBASE and Proquest Dissertations and Theses will be investigated. Data will be extracted independently by two reviewers using a standardised data extraction form. The quality of observational studies will be assessed using the National Institute of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and the quality of experimental studies will be assessed using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Study. If there is a sufficient number of studies reporting data on a similar determinant among a similar population (k>5), a meta-analysis of the results will be performed with a random-effects model. If between-study heterogeneity is high (I² ≥75%), it will be investigated through sensitivity analyses and meta-regression.

ETHICS AND DISSEMINATION

Formal ethical approval is not required as no primary data will be collected. The results will be published in a peer-reviewed journal. This review will provide valuable information to those interested in developing empirically based sleep interventions among women.

PROSPERO REGISTRATION NUMBER

CRD42017056894.

Efficacy of oral versus insulin therapy for newly diagnosed diabetes in low-income settings

BACKGROUND

There are conflicting recommendations and highly variable practices regarding the level of A1c to initiate insulin for individuals with newly diagnosed diabetes. This is complicated in low-income settings where adverse reactions or negative perceptions of insulin are often magnified.

OBJECTIVES

Compare the clinical outcomes of insulin and Oral Agents (OAs) in low-income settings in the United States.

METHODS

We conducted a retrospective chart review in community clinics serving low -income individuals with newly diagnosed type 2 diabetes who were initiated on insulin or OAs. The primary outcome was change of hemoglobin A1c (A1c) from baseline to 12 months. Secondary outcomes consisted of other clinical measures including Emergency Department (ED) visits.

RESULTS

A total of 18% (88/489) of patients were started on insulin. The adjusted average decrease of A1c from baseline was greater in the OA group (insulin: -1.97% vs. OA: -2.52%; p<0.001). In a subset analysis of individuals with A1cs >11%, significantly more patients were started on OAs (insulin: n=51, OA: n=93; p<0.001) and A1c improvements were similar at 12 months (insulin: -5.06% [12.94% to 7.88%] OA: -4.62% [12.57% to 7.96%]; p=0.846). Baseline A1c predicted insulin initiation (p<0.001): For every one-unit increase in baseline A1c, the odds of insulin initiation increased by 47.5%. Individuals in the insulin group had more ED visits per year (0.169 vs. 0.0025; p<0.005).

CONCLUSIONS

Given the positive clinical outcomes of OAs even with markedly elevated A1c levels in addition to the healthcare system benefits, they are a promising initial therapy for low-income adults with newly diagnosed type 2 diabetes.

Impact of parental weight status on a school-based weight management programme designed for Mexican-American children

BACKGROUND

While overweight and obese children are more likely to have overweight or obese parents, less is known about the effect of parental weight status on children's success in weight management programmes.

OBJECTIVES

This study was a secondary data analysis of a randomized controlled trial and investigated the impact of having zero, one or two obese parents on children's success in a school-based weight management programme.

METHODS

Sixty-one Mexican-American children participated in a 24-week school-based weight management intervention which took place in 2005-2006. Children's heights and weights were measured at baseline, 3, 6 and 12 months. Parental weight status was assessed at baseline. Repeated measures anova and ancova were conducted to compare changes in children's weight within and between groups, respectively.

RESULTS

Within-group comparisons revealed that the intervention led to significant decreases in standardized body mass index (zBMI) for children with zero (F = 23.16, P < .001) or one obese (F = 4.99, P < .05) parent. Between-group comparisons indicated that children with zero and one obese parents demonstrated greater decreases in zBMI compared to children with two obese parents at every time point.

CONCLUSIONS

The school-based weight management programme appears to be most efficacious for children with one or no obese parents compared to children with two obese parents. These results demonstrate the need to consider parental weight status when engaging in childhood weight management efforts.

Obesity status trajectory groups among elementary school children

BACKGROUND

Little is known about patterns in the transition from healthy weight to overweight or obesity during the elementary school years. This study examined whether there were distinct body mass index (BMI) trajectory groups among elementary school children, and predictors of trajectory group membership.

METHODS

This is a secondary analysis of 1651 elementary school children with complete biannual longitudinal data from kindergarten to the beginning of 5(th) grade. Heights and weights were measured by trained school nurses using standard procedures at the beginning and end of each school year for 11 consecutive assessments. Group-based trajectory clustering and multinomial logit modeling were conducted.

RESULTS

When using BMIz score, six trajectory groups were identified revealing substantial consistency in BMIz score across time. When using a categorical variable separating overweight/obese children (BMI ≥ 85%ile) from the rest, five developmental trajectories (persistently non-overweight/obese weight: 51.1 %; early-onset overweight/obese: 9.2 %; late-onset overweight/obese: 9.7 %; becoming healthy weight: 8.2 %; and chronically overweight/obese: 21.8 %) were identified. When using a categorical variable separating obese children (BMI ≥ 95%ile) from the rest, three trajectories (persistently non-obese: 74.1 %, becoming obese: 12.8 %; and chronically obese: 13.2 %) were identified. For both cutoffs (≥ BMI percentile 85 % or 95 %), girls were more likely than boys to be classified in the persistently non-overweight and/or obese group (odds ratios (OR) ranged from 0.53 to 0.67); and Hispanic children and non-Hispanic Black children were more likely to be chronically overweight and/or obese than non-Hispanic White children (OR ranged from 1.57 to 2.44). Hispanic children were also more likely to become obese (OR: 1.84) than non-Hispanic White children when ≥ BMI percentile 95 % was used.

CONCLUSIONS

Boys, Hispanic and non-Hispanic Black children were at higher risk of being overweight or obese throughout their elementary school years, supporting the need for obesity treatment. Post kindergarten and post second grade summer months were times when some children transitioned into overweight/obesity. It will be important to identify which behavioral factors (e.g., diet, physical activity, sedentary behaviors, and/or sleep) predisposed children to becoming overweight/obese, and whether these factors differ by time (Kindergarten versus second grade). If behavioral predisposing factors could be identified early, targeted obesity prevention should be offered.

Obesity status transitions across the elementary years: use of Markov chain modelling

OBJECTIVE

The objective of this study was to assess overweight and obesity status transition probabilities using first-order Markov transition models applied to elementary school children.

METHOD

Complete longitudinal data across 11 assessments were available from 1494 elementary school children (from 7599 students in 41 out of 45 schools in a Southeast Texas school district) from kindergarten to the beginning of the fifth grade. Heights and weights were measured by trained school nurses using standard procedures at the beginning and end of each school year for the 11 consecutive assessments. To estimate the transition probabilities, first-order three-state (healthy weight, overweight and obese) Markov transition models were fit to the longitudinal weight status data of all assessment periods.

RESULTS

While there was a gradual shift to more children in the overweight or obese category over 5 years, children were most likely to stay in the same weight category as the previous assessment. A consistent seasonal difference in the probability of changing weight status category was seen, with a greater probability of becoming overweight and obese during the summer compared with the school year. The transition probabilities to obesity were higher among boys, Hispanic and non-Hispanic Black, and lower socioeconomic status children.

CONCLUSIONS

This study provides the first application of a Markov transition model to child weight status data. The transitions into the overweight and obese categories were small, but persistent, with smaller percentages transitioning out of overweight or obese. Early monitoring and summer intervention strategies are needed to prevent the slow, but relentless, transition into the overweight and obese categories.

Bridging the Science-Practice Gap in Obesity Treatment

The number of putative causes of obesity continues to increase at a rapid rate. As science identifies novel causes of obesity, innovations in the treatment of obesity also evolve. These innovations have important implications for clinical practice; however, a gap exists between research and the clinical application of research. Practical considerations about how to address this gap between research and practice are discussed.

The Difficulty of Prevention: A Behavioral Perspective

Behavioral medicine provides insight in to the problem of injury prevention. Society often views unintentional injuries as only an accident when in reality many accident-related injuries are preventable. However, barriers to behavioral change in injury prevention exist for both patients (eg, inconvenience, perceived risk-benefit ratio) and health care providers (eg, feeling of badgering nonadherent patients, patient misinformation). To overcome barriers, the article discusses strategies for health care providers to address injury prevention such as choosing active over passive strategies, informing patients of predictable injury-prone circumstances, and individualizing patient risks.

Creating Behavioral Vacuums

Screen media use has increased dramatically in children in the past decade, contributing to increasing rates of sedentary behavior in children. Excessive screen media use is related to poor social skills and increased likelihood of being overweight and obese. Behavioral economic theory has been used to examine the relationship between sedentary behavior and physical activity and whether an increase or decrease in one leads to a reciprocal response in the other. Health care providers should be aware of the behavioral “vacuum” that is created when patients are told to decrease sedentary behavior and assist patients with filling that void with nonsedentary behaviors.

Utilizing the One-Minute Preceptor for Patient Education

Providing thorough responses to patient questions is an important part of the provider–patient relationship and key to good communication. Failure to do so puts patients at risk of looking for alternative and possibly harmful answers. Mindfulness is a popular topic, but due to its vague definition and variable outcomes, it may be difficult for health care providers to know how to answer patient questions or to identify patient needs. Using the One-Minute Preceptor model as a template provides health care providers a thorough yet organized and time-efficient method while also giving patients answers to their questions.

Smoking Cessation

Smoking prevalence rates have substantially decreased among both adults and adolescents in the past 15 years. The decreasing rates are largely because of the effectiveness of tobacco control initiatives, including bans on smoking, increases in tobacco taxes, and behavioral interventions; yet a minority of people continue to smoke. It is possible that these individuals may be more resistant than others to smoking cessation interventions. As a result, it is important to intervene systematically. Brief advice offered in a primary care setting is well established as an effective strategy to promote smoking cessation. Barriers to providing smoking cessation in a primary care setting are discussed, and methods to enhance these efforts through consistent screening for tobacco use, use of motivational techniques, brief follow-up after quit attempts, and use of pharmacotherapy are provided.

Seasonal variability in weight change during elementary school

OBJECTIVE

To examine seasonal variation in weight gain across elementary school (kindergarten-5th grade) among children who are healthy weight, overweight, or obese and from different racial and ethnic groups.

METHODS

The sample included 7,599 ethnically diverse students ages 5-7 years at baseline (Caucasian: 21.1%, Black: 36.2%, Hispanic: 26.0%, Asian 16.7%). Heights and weights were measured by school nurses at the beginning and end of each school year from kindergarten through the beginning of 5th grade.

RESULTS

Beginning the summer after 1st grade, all children demonstrated a pattern of standardized BMI (zBMI) increases during the summer (0.04 to 0.09) and zBMI decreases across the school years (-0.06 to 0.00; P<0.0001). Hispanic children and children who were overweight and obese exhibited this pattern in kindergarten while children of other ethnicities and with a healthy weight did not (P<0.0001).

CONCLUSIONS

Beginning the summer after 1st grade, a consistent pattern of relative weight gain during the summer months (Δ in BMI percentile=1.04) and weight loss during the school year (Δ in BMI percentile=-0.34) emerged. This pattern appeared earlier for children who were overweight, obese, or Hispanic. These findings suggest a need to better understand the causes of the problematic increases in weight during the summer.

Impact of human leukocyte antigen molecules E, F, and G on the outcome of transplantation

BACKGROUND

HLA class I molecules are divided into classic (Ia) and nonclassic (Ib). Nonclassic HLA molecules (E, F, and G) have acquired relevance owing to their immunomodulatory properties and possible repercussions for induction of tolerance in organ transplantation. The objective of this study was to identify the impact of these molecules on transplant success or failure.

METHODS

A systematic review of literature was performed with the use of MeSH terms in Pubmed. Clinical trials, randomized clinical trials, case-control studies, and reviews from the past 15 years were included.

RESULTS

HLA-E*0103/E*0103 genotype is associated with lower risk of graft-versus-host disease, decreased mortality, and greater disease-free survival after bone marrow transplantation. There were no significant associations between HLA-F and clinical outcomes in any of the studies. Elevated serum levels of HLA-G were associated with a lower incidence of rejection in hepatic and renal transplantation during the 1st year and lower T-cell response after bone marrow, liver, and kidney transplantation. Detection of mRNA of HLA-G1 was also associated with less graft rejection.

CONCLUSIONS

Current literature suggests that nonclassic HLA Ib molecules play an important role in immunotolerance in organ transplantation; however, more studies are required to predict outcomes related to specific genotypes.

Sleep Is Not for Slackers

Sufficient sleep is as important as healthy eating and regular exercise to maintain a healthy lifestyle. However, many individuals do not obtain enough sleep or follow healthy sleep hygiene recommendations. The interaction of both biological and behavioral factors may affect sleep. Recommendations of healthy sleep habits that may assist in improving sleep quality and quantity are discussed in this article.

Considering the Impact of Acculturation on Lifestyle Interventions for Latinos

Individuals of Latino descent are one of the fastest growing groups in the United States. They also experience multiple health disparities. To effectively treat individuals from these cultures, several issues should be considered. Assessing the degree of an individual’s acculturation and tailoring interventions to be more compatible with a patient’s cultural values are important steps to be taken.

Promotion of Long-Term Adherence to a Healthy Lifestyle

The prevalence of chronic diseases including dyslipidemia has increased as the prevalence of healthy lifestyles has decreased. Intensive interventions targeting lifestyle management of chronic diseases have proven effective in producing meaningful outcomes in research settings. However, it is not clear whether the comprehensive and intensive components of these interventions could be translated into real-world clinical and community settings. There are certain barriers that health care providers should consider when counseling patients.

Barriers to Physical Activity in Women

Despite the clear benefits of physical activity for women, few women obtain the recommended levels of physical activity. To address adherence to physical activity in this group, it is important to understand the barriers to physical activity that affect women. These barriers may include lack of time; anticipated lack of enjoyment; self-consciousness about body size, shape, and physical activity ability; and urinary incontinence. By addressing barriers to physical activity, health care providers may experience greater success in their efforts to increase physical activity in their female patients.

Pregnancy

Pregnancy is a time when women are at increased risk to gain substantial weight. It is also a time when women are more health conscious and may be more likely to engage in healthier behaviors. Because of these factors, women are primed to engage in lifestyle strategies to promote healthy weight gain during pregnancy. Similarly, mothers of newborns also have an increased readiness for change, making infancy an ideal time to begin obesity prevention efforts in families. Health care providers are encouraged to take advantage of the increased health awareness and the behavioral momentum that is present surrounding pregnancy in order to promote healthy lifestyle changes for both pregnant women and new mothers.

A randomized controlled trial of a community-based behavioral counseling program

BACKGROUND

The US Preventive Services Task Force (USPSTF) recommends that clinicians refer obese adults for intensive, multicomponent behavioral counseling, yet most obese Americans choose a self-help approach to lose weight. The current study examined weight loss between a community-based, intensive behavioral counseling program (Weight Watchers program) and a self-help condition.

METHODS

A total of 292 participants were randomized to either a Weight Watchers condition (WW) (n = 147) or a self-help condition (n = 145). Participants in the WW condition were provided with 3 ways to access the treatment: weekly meetings; WW mobile application; and WW online tools. Weights were measured at baseline and at 3 and 6 months. Additionally, self-report use of access modes was collected at 3 and 6 months.

RESULTS

Participants in the WW condition significantly decreased their body mass index at 6 months (F = 36.7, P <.001) and were 8.0 and 8.8 times more likely to achieve a 5% and 10% reduction in weight, respectively, compared with those in the self-help condition. In a secondary analysis, high usage of all 3 access modes resulted in the greatest weight loss (P <.001).

CONCLUSION

Use of the WW program yielded significantly greater weight loss than a self-help approach, suggesting it is a viable community-based provider of weight loss treatment, as recommended by the USPSTF. Further, high usage of 3 access modes was associated with greater weight loss results.

Changes in weight over the school year and summer vacation: results of a 5-year longitudinal study

BACKGROUND

Evidence suggests that children gain more weight during the summer months compared with the school year. To examine the impact of the school and summer environment on children's weight further, we conducted a 5-year longitudinal study examining changes in standardized BMI (zBMI) of students entering kindergarten.

METHODS

Heights and weights were obtained at the beginning and end of each school year for 3,588 ethnically diverse (Caucasian: 27.2%, Black: 29.0%, Hispanic: 26.4%, and Asian 17.4%) students aged 5-7.

RESULTS

A significant difference in change in zBMI during the school and summer months was found (-0.52, 95% CI: -0.59 to -0.45, p < .001; Wald χ2 = 171.89, p < .001). Overall, children decreased BMI percentile during time spent in school by 1.5 percentile points and increased by 5.2 percentile points during summer months. Differences in the velocity of weight gain were found across weight classification categories with only overweight and obese children decreasing their zBMI during the school year.

CONCLUSION

Time spent in school was shown to have a beneficial impact on students' weight, especially for students who were overweight or obese. However, these results are alarming because weight gain during elementary school occurs primarily during the relatively short span of summer break.

Impact of a school-based pediatric obesity prevention program facilitated by health professionals

BACKGROUND

This study evaluated a school-based obesity intervention for elementary school children (N = 835) where health professionals assisted teachers with the integration of healthy messages into the school curriculum.

METHODS

Schools were randomized into a professional-facilitated intervention (PFI; N = 4) or a self-help (SH; N = 3) condition. Changes in weight-based outcomes were assessed in students enrolled in the second grade from all 7 schools (overall: N = 835 students; PFI: N = 509 students, SH: N = 326 students). Students were between ages 7 and 9 and from diverse ethnic backgrounds (Asian = 25.3%, Black = 23.3%, Hispanic = 23.1%, White = 28.3%). The sample included 321 overweight/obese (BMI ≥ 85th percentile), 477 normal-weight (BMI ≥ 5th percentile and <85th percentile), and 37 underweight (BMI < 5th percentile) students.

RESULTS

After 2 years, children who were overweight/obese in the PFI condition significantly reduced their standardized BMI (zBMI) compared to children in the SH condition (Wald χ(2)  = 28.7, p < .001). End-of-year grades decreased for overweight/obese students in both conditions; however, students in the PFI exhibited a smaller decrease in grades compared to the SH condition (Wald χ(2)  = 80.3, p < .001).

CONCLUSION

The results indicate that an obesity prevention program where health professionals assist teachers by integrating healthy messages into existing curriculum was effective in reducing zBMI compared to the SH condition.

School lunches and lunches brought from home: a comparative analysis

BACKGROUND

Considerable effort has been put forth to improve the nutritional quality of school meals by the National School Lunch Program (NSLP). However, a large percentage of children do not obtain their meals from school and instead bring lunch from home. Little research has focused on the content of these lunches. The purpose of the current study was to examine differences between school lunch and lunch brought from home.

METHODS

Children in the 2nd grade from seven schools in a large suburban school district were observed on three separate days. A total of 2107 observations were made, with 38.5% of these being lunches brought from home. Chi-squared analyses evaluated differences in the presence of specific food items between school lunch and lunch brought from home.

RESULTS

Compared to children with a school lunch, children with a lunch brought from home were significantly less likely to have fruits (75.9% vs. 45.3%), vegetables (29.1% vs. 13.2%), and dairy (70.0% vs. 41.8%) (p < 0.001). Children with a lunch from home were more likely to have snacks high in sugar and/or fat (17.5% vs. 60.0%) and non 100% fruit juice/fruit drink (0.3% vs. 47.2%) (p < 0.001) than children with a school lunch.

CONCLUSIONS

The NSLP has been widely criticized; however, conducting a comparison in this manner demonstrates advantages to children obtaining school lunches. Although it was beyond the scope of this study to examine diet quality (e.g., actual intake and nutrient/caloric density), these results provide compelling evidence that lunches brought from home should be an area of emphasis for research and intervention.

Obese Mexican American children have elevated MCP-1, TNF-α, monocyte concentration, and dyslipidemia

BACKGROUND AND OBJECTIVE

Obesity is an independent risk factor for chronic disease. The prevalence of obesity is especially high among Mexican American children. Peripheral blood monocytes are altered with obesity contributing to elevated systemic inflammation and increased risk of chronic disease. In addition, obesity alters the circulating levels of cytokines/chemokines that influence monocyte behavior. The study objective was to investigate alterations in blood monocytes and plasma cytokines/chemokine levels among healthy weight (standardized BMI [zBMI] ≤85th percentile; n = 66), overweight (zBMI 85th-95th percentile; n = 23), and obese (zBMI ≥95th percentile; n = 39) Mexican American children.

METHODS

Blood samples were analyzed for total and subset monocyte concentration via flow cytometry. Serum monocyte chemoattractant protein-1 (MCP-1), fractalkine, interleukin-8, and tumor necrosis factor α (TNF-α) were measured by using a Milliplex MagPix assay. Serum cholesterol, high-density lipoproteins, triglycerides, and glucose were measured by using an enzymatic assay.

RESULTS

Total monocyte concentration (P = .012), classic monocyte concentration (P = .045), MCP-1 (P = .015), and TNF-α (P = .002) were significantly greater in obese children compared with healthy weight children. Also, overweight and obese children had elevated triglycerides (P = .001) and reduced high-density lipoproteins (P = .033) compared with healthy weight children.

CONCLUSIONS

Childhood obesity alters monocytes and circulating chemokines, putting children at a greater risk of developing obesity-related chronic diseases in adulthood. Further characterization of early immune alterations in childhood obesity may provide additional clinical insight into the assessment of obesity-related disease risk.

Lifestyle Modification

Early detection of cancer through screening is an important step in decreasing both morbidity and mortality. Likewise, specific modifiable lifestyle behaviors are associated with reduced risk of colorectal cancer. Lifestyle practices have also been shown to maximize health after the primary treatment of cancer. Both these roles for lifestyle interventions are discussed.