Association of salivary alpha-amylase and salivary flow rate with working memory functioning in healthy children.

The aim of this study was to examine the association between auditory and visual working memory (WM) performance and salivary alpha-amylase (sAA) and salivary flow rate (SFR) in a sample of 63 children (38 boys). WM was assessed by means of WISC-V subtests: four auditory subtests (Digit Span and Letter-Number Sequencing) and one visual subtest (Picture Span). SAA activity, output, and SFR were measured at baseline (10 min prior to testing), one minute prior to testing, one minute after the end of the auditory WM subtests and one minute after the end of the visual WM subtest. Our statistical analyses showed an association among SAA activity, output and SFR levels and the number of recalled digits in the last attempt score in Letter-Number Sequencing subtest. Specifically, our results showed that working performance in this task was associated with a concurrent decrease in SFR (r(63) = -0.423, p < .05). This salivary measure was the best predictor of this specific index of working memory performance (ß = -0.423, p < .05). These results show that the changes in SFR, which represents changes in parasympathetic tone, could be employed in future studies as a noninvasive marker of working memory performance in child studies.

Association between Salivary Alpha-Amylase and Executive Functioning in Healthy Children.

The main aim of this study was to confirm the relationship between executive performance and salivary alpha-amylase (SAA) activity in a sample of 64 healthy children (39 boys), and compare it to the association of SAA output and salivary flow rate (SFR). Executive functioning was assessed via fluency, trail-making, rings and inhibition tasks from the Batería de Evaluación Neuropsicológica de la Función Ejecutiva en Niños [Battery of Neuropsychological Assessment for Executive Function in Children] (ENFEN), merged into an ENFEN total score. SAA activity, output, and SFR were measured at baseline, one minute before, and one minute after the end of a neuropsychological testing session. Our results confirmed a direct, linear and significant association between SAA activity and executive functioning, r(64) = .351, p < .05, and extended it to SAA output, r(64) =.431, p < .05. The mean level of SAA output was the best predictor of executive functioning (ß = .431, p < .05) and explained 18.2 % of the variance in ENFEN total score. In sum, and compared to SAA activity, measuring SAA output may be a more precise and indirect marker to assess executive functioning in children.

Neighborhood Socioeconomic Status and Feeding Practices in Finnish preschools.

Aims: Certain feeding practices, such as role modeling healthy eating and encouragement are recommended to be used in preschools. Little is known about whether preschool characteristics are associated with the use of these feeding practices. Our aim was to examine whether the socioeconomic status (SES) of the preschool neighborhood is associated with the feeding practices in preschools. Methods: This study was part of the cross-sectional DAGIS study. We studied 66 municipal preschools and 378 early childhood educators (ECEs). Preschool neighborhood SES was assessed with map grid data. Feeding practices were assessed by questionnaires and lunchtime observation. Associations between preschool neighborhood SES and feeding practices were tested with logistic regression analyses adjusted for ECEs' educational level and municipal policies on ECEs' lunch prices, and on birthday foods. Results: The crude model showed that in high-SES neighborhood preschools ECEs were more likely to eat the same lunch as the children (OR 2.46, 95% CI 1.42-4.24) and to reward children with other food for eating vegetables (OR 2.48, 95% CI 1.40-4.41). Furthermore, in high-SES preschools it was less likely that birthday foods outside of the normal menu were available on birthdays (OR 0.29, 95% CI 0.12-0.71). In the adjusted model, rewarding with other food remained associated with preschool neighborhood SES (OR 2.13, 95% CI 1.12-4.07). Conclusions: After adjustments, preschool neighborhood SES was mostly unassociated with the feeding practices in preschools. Municipal policies may have a significant impact on feeding practices and ultimately on young children's food intake in Finland where most children attend municipal preschools.

Increased Health and Wellbeing in Preschools (DAGIS) Study-Differences in Children's Energy Balance-Related Behaviors (EBRBs) and in Long-Term Stress by Parental Educational Level.

This paper describes the Increased Health and Wellbeing in Preschools (DAGIS) survey process and socioeconomic status (SES) differences in children's energy balance-related behaviors (EBRBs), meaning physical activity, sedentary and dietary behaviors, and long-term stress that serve as the basis for the intervention development. A cross-sectional survey was conducted during 2015⁻2016 in 66 Finnish preschools in eight municipalities involving 864 children (3⁻6 years old). Parents, preschool personnel, and principals assessed environmental factors at home and preschool with questionnaires. Measurement of children's EBRBs involved three-day food records, food frequency questionnaires (FFQ), seven-day accelerometer data, and seven-day sedentary behavior diaries. Children's long-term stress was measured by hair cortisol concentration. Parental educational level (PEL) served as an indicator of SES. Children with low PEL had more screen time, more frequent consumption of sugary beverages and lower consumption of vegetables, fruit, and berries (VFB) than those with high PEL. Children with middle PEL had a higher risk of consuming sugary everyday foods than children with high PEL. No PEL differences were found in children's physical activity, sedentary time, or long-term stress. The DAGIS intervention, aiming to diminish SES differences in preschool children's EBRBs, needs to have a special focus on screen time and consumption of sugary foods and beverages, and VFB.

Increased health and well-being in preschools (DAGIS): rationale and design for a randomized controlled trial.

BACKGROUND: Effective interventions that target socioeconomic status (SES) differences to avoid the potential widening of inequalities in health are needed. Children at preschool age is a valuable intervention target since sedentary behaviors, physical activity (PA), dietary behaviors, and sleep habits, jointly called the energy balance-related behaviors (EBRBs), are established in early childhood and tend to persist later in life. The interventions are most effective, when they focus on evidence-based factors. One potential factor associated with EBRBs and SES is children's stress regulation, which receives special attention in this study. Based on the socioecological approach, the combinations of multiple levels (e.g. individual, environmental, societal) of analysis and diverse methodologies (e.g. surveys, observations, biological measurements) are used to assess the healthfulness of environments (e.g. social, physical, learning, policy) in preschool and family settings. The intervention aimed to diminish SES differences in EBRBs is then conducted in the preschool setting. METHODS/DESIGN: The DAGIS study is divided into two phases. The first phase comprises focus group interviews and a cross-sectional survey. Parents and preschool personnel in low SES neighborhoods participated in interviews about children's sedentary behaviors, dietary behaviors, and PA in 2014. In the cross-sectional survey beginning in autumn 2015, preschools will be recruited from a random sample of preschools in 3-5 municipalities in Southern Finland. A total of 800 children will wear an accelerometer for seven days. Children's hair and saliva samples will be taken. Parents and preschool personnel will complete questionnaires on EBRBs, social and physical environments and SES factors. The quality of preschool environment is also observed. In the second phase, an intervention targeting to narrowing SES differences in EBRBs is conducted. The effects of the intervention will be evaluated in randomised controlled trial. The implementation of the intervention will also be evaluated. CONCLUSION: If effective, this unique preschool-based study will be able to narrow the SES differences in preschool children's EBRBs. This study is anticipated to identify the most important modifiable factors in preschool and family environmental settings associated with children's EBRBs, especially in children from low SES backgrounds. TRIAL REGISTRATION: ISRCTN57165350 (January, 8th, 2015).