School Poverty Level Moderates the Effectiveness of a Physical Activity Intervention.

PURPOSE: To explore whether school poverty level and funding modified the effectiveness of an evidence-based Comprehensive School Physical Activity Program called Health Empowers You! implemented in elementary schools in Georgia. DESIGN: Secondary data analysis of a multi-level, cluster-randomized controlled trial. SETTING: 40 elementary schools in Georgia in 2018-2019. SUBJECTS: 4th grade students in Georgia. MEASURES: Intervention schools implemented the Health Empowers You! program to increase school-day physical activity. The outcome was average daily moderate-to-vigorous physical activity, school free-reduced price lunch (FRPL) percentage and per pupil expenditures were effect modifiers. ANALYSIS: Separate linear mixed regression models estimated the effect of the intervention on average daily moderate-to-vigorous physical activity, with interaction terms between intervention status and (1) school FRPL percentage or (2) per pupil expenditures. RESULTS: The effect of the intervention was significantly higher in schools with higher FRPL percentage (intervention*school % FRPL ß (95% CI): .06 (.01, .12)), and was modestly, but not statistically significantly, higher in schools with lower per pupil expenditures. CONCLUSION: Findings support the use of the Health Empowers You! intervention, which was effective in lower income schools, and may potentially reduce disparities in students' physical activity levels.

The Association of Sleep Duration with Grade Point Averages and Absences Among 9th Graders in Georgia, USA.

This study aimed to examine the association between sleep measures (self-reported sleep duration and weekend catch-up sleep) and grade point average (GPA) and absences among 9th grade students from two racially and economically diverse high schools in a semi-rural county of north-central Georgia. Linear and Poisson regression models estimated the association between sleep measures and GPA and absences (separately), respectively. Analyses adjusted for gender, race/ethnicity, free/reduced-price school lunch status, and parental education. Sleep duration was significantly associated with both GPA and absences, such that for every one additional hour of sleep, GPA increased by 0.8 percentage points (b=0.8, 95% CI:0.1,1.5) while the number of absences was lower by 6% (b=-0.05; OR=0.94, 95% CI:0.91,0.98). Weekend catch-up sleep was also significantly and positively associated with absences (b=0.04; OR=1.04, 95% CI; 1.02, 1.07). Increasing sleep may be a strategy to improve GPA and reduce absences among teenagers. Future research should identify effective measures to lengthen sleep.

Factors That Influence Sleep Behaviors of High School Students: Findings From a Semi-Rural Community in Georgia.

BACKGROUND: Inadequate sleep has been shown to have detrimental effects on academic performance, physical, mental, and emotional health among adolescents. Factors that influence sleep have been identified. However, most literature is currently limited to urban settings. This study sought to identify factors that influence sleep habits among high school students in a semi-rural community. METHODS: Twelve focus groups were conducted in-person with separate groups of students, parents, and school staff in October 2019. Discussions focused on sleep experiences, knowledge, environment, and factors influencing sleep. Data were coded using grounded theory approach. Themes were identified through summative content analysis. RESULTS: Four major themes were identified: (1) inadequate sleep adversely affects academic performance and emotional health; (2) students face a gap in knowledge regarding sleep duration; (3) academic and nonacademic activities compete with sleep needs; and (4) night-time use of technology negatively influences sleep habits. CONCLUSIONS: Our findings suggest that high school students do not get adequate sleep, largely due to the demands of academic and extracurricular activities and the use of electronics at night. These results can guide the development of targeted sleep education and intervention programs.

Epidemiology beyond its limits.

In 1995, journalist Gary Taubes published an article in Science titled "Epidemiology faces its limits," which questioned the utility of nonrandomized epidemiologic research and has since been cited more than 1000 times. He highlighted numerous examples of research topics he viewed as having questionable merit. Studies have since accumulated for these associations. We systematically evaluated current evidence of 53 example associations discussed in the article. Approximately one-quarter of those presented as doubtful are now widely viewed as causal based on current evaluations of the public health consensus. They include associations between alcohol consumption and breast cancer, residential radon exposure and lung cancer, and the use of tanning devices and melanoma. This history should inform current debates about the reproducibility of epidemiologic research results.

The Relationships between Childhood Bullying, School Connectedness, and Adolescent Adiposity, the Fragile Families Child and Wellbeing Study.

BACKGROUND: School environments are important to consider for children's health. This study aims to determine if childhood peer bullying and school connectedness are associated with adolescent adiposity. METHODS: A total of 3377 children from the age 9 child interview of the Fragile Families and Child Wellbeing Study had self-reported bullying and school connectedness data at age 9, height and weight measured at ages 9 and 15, and waist circumference was measured during an age 15 home visit. Linear regression models estimated the association between bullying and school connectedness and (1) change in BMI between age 9 and 15, and (2) waist circumference at age 15. Models were stratified by sex. RESULTS: Girls had larger increases in body mass index (BMI) when experiencing low school connectedness, and students that experienced both bullying and low school connectedness had larger increases in BMI. Girls had larger waist circumferences for increased levels of bullying, low connectedness, and experiencing both. CONCLUSIONS: School environments may play a role in the development of increased adiposity and there may be gender differences in the types of factors that are important to consider, particularly for central adiposity. Positive and engaging school environments can help support students' development and healthy behaviors.

Dietary Sodium Intake and Health Indicators: A Systematic Review of Published Literature between January 2015 and December 2019.

As the science surrounding population sodium reduction evolves, monitoring and evaluating new studies on intake and health can help increase our understanding of the associated benefits and risks. Here we describe a systematic review of recent studies on sodium intake and health, examine the risk of bias (ROB) of selected studies, and provide direction for future research. Seven online databases were searched monthly from January 2015 to December 2019. We selected human studies that met specified population, intervention, comparison, outcome, time, setting/study design (PICOTS) criteria and abstracted attributes related to the study population, design, intervention, exposure, and outcomes, and evaluated ROB for the subset of studies on sodium intake and cardiovascular disease risks or indicators. Of 41,601 abstracts reviewed, 231 studies were identified that met the PICOTS criteria and ROB was assessed for 54 studies. One hundred and fifty-seven (68%) studies were observational and 161 (70%) focused on the general population. Five types of sodium interventions and a variety of urinary and dietary measurement methods were used to establish and quantify sodium intake. Five observational studies used multiple 24-h urine collections to assess sodium intake. Evidence mainly focused on cardiovascular-related indicators (48%) but encompassed an assortment of outcomes. Studies varied in ROB domains and 87% of studies evaluated were missing information on ≥1 domains. Two or more studies on each of 12 outcomes (e.g., cognition) not previously included in systematic reviews and 9 new studies at low ROB suggest the need for ongoing or updated systematic reviews of evidence on sodium intake and health. Summarizing evidence from assessments on sodium and health outcomes was limited by the various methods used to measure sodium intake and outcomes, as well as lack of details related to study design and conduct. In line with research recommendations identified by the National Academies of Science, future research is needed to identify and standardize methods for measuring sodium intake.

Self-Reported Measures of Discretionary Salt Use Accurately Estimated Sodium Intake Overall but not in Certain Subgroups of US Adults from 3 Geographic Regions in the Salt Sources Study.

BACKGROUND: Excess sodium intake can increase blood pressure, and high blood pressure is a major risk factor for cardiovascular disease. Accurate population sodium intake estimates are essential for monitoring progress toward reduction, but data are limited on the amount of sodium consumed from discretionary salt. OBJECTIVES: The aim of this study was to compare measured sodium intake from salt added at the table with that estimated according to the Healthy People 2020 (HP 2020) methodology. METHODS: Data were analyzed from the 2014 Salt Sources Study, a cross-sectional convenience sample of 450 white, black, Asian, and Hispanic adults living in Alabama, Minnesota, and California. Sodium intake from foods and beverages was assessed for each participant through the use of 24-h dietary recalls. Estimated sodium intake from salt used at the table was assessed from self-reported frequency and estimated amounts from a previous study (HP 2020 methodology). Measured intake was assessed through the use of duplicate salt samples collected on recall days. RESULTS: Among all study participants, estimated and measured mean sodium intakes from salt added at the table were similar, with a nonsignificant difference of 8.9 mg/d (95% CI: -36.6, 54.4 mg/d). Among participants who were non-Hispanic Asian, Hispanic, had a bachelor's degree or higher education, lived in California or Minnesota, did not report hypertension, or had normal BMI, estimated mean sodium intake was 77-153 mg/d greater than measured intake (P < 0.05). The estimated mean sodium intake was 186-300 mg/d lower than measured intake among participants who were non-Hispanic black, had a high school degree or less, or reported hypertension (P < 0.05). CONCLUSIONS: The HP 2020 methodology for estimating sodium consumed from salt added at the table may be appropriate for the general US adult population; however, it underestimates intake in certain population subgroups, particularly non-Hispanic black, those with a high school degree or less, or those with self-reported hypertension. This study was registered at clinicaltrials.gov as NCT02474693.

Obesity and understudied minority children: existing challenges and opportunities in epidemiology.

BACKGROUND: Obesity is a major public health concern in the United States and should be addressed as early as possible, in childhood. Disparities exist in obesity prevalence and its associated comorbidities by racial/ethnic group, however less is known about the smaller racial/ethnic subclasses that are often aggregated and assumed to be homogeneously at risk. As the racial and ethnic composition of the US shifts towards greater diversity, it is important that epidemiologic research addresses these new challenges. MAIN BODY: In this short communication, we focus on Asian American children given that subgroups are historically understudied and emerging evidence among adults suggest heterogeneous associations for both obesity and cardio-metabolic outcomes. Existing limitations in this research area include: (1) identifying the appropriate measurement of adiposity in Asian American children; (2) determining high-risk cutoffs for intervention; and (3) developing strategies to ensure study robustness. CONCLUSION: Data disaggregation is a necessary approach to understand potentially heterogeneous associations in childhood obesity and cardio-metabolic risk, but epidemiologic investigators must address these challenges. Ultimately, successful strategies could help better identify high risk subgroups, target interventions, and effectively reduce the burden of obesity among American youth.

Changes in primary healthcare providers' attitudes and counseling behaviors related to dietary sodium reduction, DocStyles 2010 and 2015.

High blood pressure is a major risk factor for cardiovascular disease. The 2013 ACC/AHA Lifestyle Management Guideline recommends counseling pre-hypertensive and hypertensive patients to reduce sodium intake. Population sodium reduction efforts have been introduced in recent years, and dietary guidelines continued to emphasize sodium reduction in 2010 and 2015. The objective of this analysis was to determine changes in primary health care providers' sodium-reduction attitudes and counseling between 2010 and 2015. Primary care internists, family/general practitioners, and nurse practitioners answered questions about sodium-related attitudes and counseling behaviors in DocStyles, a repeated cross-sectional web-based survey in the United States. Differences in responses between years were examined. In 2015, the majority (78%) of participants (n = 1,251) agreed that most of their patients should reduce sodium intake, and reported advising hypertensive (85%), and chronic kidney disease patients (71%), but not diabetic patients (48%) and African-American patients (43%) to consume less salt. Since 2010, the proportion of participants agreeing their patients should reduce sodium intake decreased while the proportion advising patients with these characteristics to consume less salt increased and the prevalence of specific types of advice declined. Changes in behaviors between surveys remained significant after adjusting for provider and practice characteristics. More providers are advising patients to consume less salt in 2015 compared to 2010; however, fewer agree their patients should reduce intake and counseling is not universally applied across patient groups at risk for hypertension. Further efforts and educational resources may be required to enable patient counseling about sodium reduction strategies.

Sodium Intake Among Persons Aged ≥2 Years - United States, 2013-2014.

High sodium consumption can increase hypertension, a major risk factor for cardiovascular diseases (1). Reducing sodium intake can lower blood pressure, and sodium reduction in the U.S. population of 40% over 10 years might save at least 280,000 lives (2). Average sodium intake in the United States remains in excess of Healthy People 2020 objectives,* and monitoring sources of sodium in the U.S. population can help focus sodium reduction measures (3,4). Data from 2013-2014 What We Eat in America (WWEIA), the dietary intake portion of the National Health and Nutrition Examination Survey (NHANES),† were analyzed to determine the ranked percentage sodium contribution of selected food categories and sources of sodium intake from all reported foods and beverages, both overall and by demographic subgroups. These latest data include updated food codes and separate estimates for intake among non-Hispanic Asians.§ In 2013-2014, 70% of dietary sodium consumed by persons in the United States came from 25 food categories; breads were the top contributor, accounting for 6% of sodium consumed. A majority of sodium consumed was from food obtained at stores; however, sodium density (mg/1,000 kcal) was highest in food obtained at restaurants. A variety of commonly consumed foods contributes to U.S. sodium intake, emphasizing the importance of sodium reduction across the food supply (4).

Sodium Intake among US School-Aged Children: National Health and Nutrition Examination Survey, 2011-2012.

BACKGROUND: Identifying current major dietary sources of sodium can enhance strategies to reduce excess sodium intake, which occurs among 90% of US school-aged children. OBJECTIVE: To describe major food sources, places obtained, and eating occasions contributing to sodium intake among US school-aged children. DESIGN: Cross-sectional analysis of data from the 2011-2012 National Health and Nutrition Examination Survey. PARTICIPANTS/SETTING: A nationally representative sample of 2,142 US children aged 6 to 18 years who completed a 24-hour dietary recall. MAIN OUTCOME MEASURES: Population proportions of sodium intake from major food categories, places, and eating occasions. STATISTICAL ANALYSES PERFORMED: Statistical analyses accounted for the complex survey design and sampling. Wald F tests and t tests were used to examine differences between subgroups. RESULTS: Average daily sodium intake was highest among adolescents aged 14 to 18 years (3,565±120 mg), lowest among girls (2,919±74 mg). Little variation was seen in average intakes or the top five sodium contributors by sociodemographic characteristics or weight status. Ten food categories contributed to almost half (48%) of US school-aged children's sodium intake, and included pizza, Mexican-mixed dishes, sandwiches, breads, cold cuts, soups, savory snacks, cheese, plain milk, and poultry. More than 80 food categories contributed to the other half of children's sodium intake. Foods obtained from stores contributed 58% of sodium intake, fast-food/pizza restaurants contributed 16%, and school cafeterias contributed 10%. Thirty-nine percent of sodium intake was consumed at dinner, 31% at lunch, 16% from snacks, and 14% at breakfast. CONCLUSIONS: With the exception of plain milk, which naturally contains sodium, the top 10 food categories contributing to US schoolchildren's sodium intake during 2011-2012 comprised foods in which sodium is added during processing or preparation. Sodium is consumed throughout the day from multiple foods and locations, highlighting the importance of sodium reduction across the US food supply.

Trends and determinants of discretionary salt use: National Health and Nutrition Examination Survey 2003-2012.

OBJECTIVE: To examine temporal trends and determinants of discretionary salt use in the USA. DESIGN: Multiple logistic regression was used to assess temporal trends in discretionary salt use at the table and during home cooking/preparation, adjusting for demographic characteristics, using data from the National Health and Nutrition Examination Survey 2003-2012. Prevalence and determinants of discretionary salt use in 2009-2012 were also examined. SETTING: Participants answered salt use questions after completing a 24 h dietary recall in a mobile examination centre. SUBJECTS: Nationally representative sample of non-institutionalized US children and adults, aged ≥2 years. RESULTS: From 2003 to 2012, the proportion of the population who reported using salt 'very often' declined; from 18 % to 12 % for use at the table (P<0·01) and from 42 % to 37 % during home cooking (P<0·02). While one-third of the population reported never adding salt at the table, most used it during home cooking/preparation (93 %). Use of discretionary salt was least commonly reported among young children and older adults and demographic and health subgroups at risk of CVD. CONCLUSIONS: While most people reported using salt during home cooking/preparation, a minority reported use at the table. Reported 'very often' discretionary salt use has declined. That discretionary salt use is less common among those at risk of CVD suggests awareness of messages to limit Na intake.