Impact of sleep duration, physical activity, and screen time on health-related quality of life in children and adolescents

Internet addiction and health-related quality of life in adolescents: The mediating role of sleep disturbance

BACKGROUND

Internet addiction (IA) has emerged as a recognized risk factor associated with impaired health-related quality of life (HRQOL) in adolescents. However, the role of sleep disturbance in this association remains unclear. This study aimed to investigate the association of IA with HRQOL in Chinese adolescents and to evaluate the potential mediating role of sleep disturbance.

METHODS

A cross-sectional study was conducted among adolescents attending six randomly selected middle schools in Guangzhou, China. Adolescents self-reported their internet use using the Young Diagnostic Questionnaire. HRQOL and sleep disturbance were assessed by the Pediatric Quality of Life Inventory version 4.0 and the Pittsburgh Sleep Quality Index, respectively. Multivariate linear regression analysis was employed to assess the association between IA and HRQOL. Baron and Kenny's causal steps method was used to examine the possible mediating role of sleep disturbance.

RESULTS

Of the 6473 adolescents included, 23.5% had maladaptive internet use (MIU) and 16.6% had pathological internet use (PIU). Compared to adolescents with adaptive internet use (AIU), those with IA had significantly lower scores across all HRQOL dimensions and summary scales. Mediation analysis revealed that sleep disturbance was a significant mediator. Specifically, sleep disturbance mediated 34.55% of the effects of MIU and 34.06% of the effects of PIU on the HRQOL total scale score , respectively.

CONCLUSIONS

IA was associated with poorer HRQOL, indicating the needs of preventing IA in Chinese adolescents. Additionally, our findings underscored the importance of enhancing sleep quality to mitigate the adverse impact of IA on adolescents' well-being.

[Screen time, quality of the adolescent diet, and profile of the school environment]

Adolescents from 30 state schools in Curitiba, State of Paraná, reported total screen time, namely television, video games and laptops. Diet quality was assessed by the frequency of food consumption. The income of the school environment was taken from the Census. The built environment for physical activity was investigated by systematic observation of the school surroundings. Multilevel Poisson Regression was used to estimate associations with the exposure variables. Among 1,200 adolescents, 50.9% being male, and 74.4% were found to be exposed to excessive screen time. Excessive TV screen time (56.5%) was associated with poor diet quality. Excessive video game time (22.0%) was lower among females (PR 0.25; 95%CI 0.18;0.36), associated with poor diet quality, lower school environment income, and the worst classification of the built environment for physical activity. Excessive use of portable screens (53.2%) tended to increase with the income of the school environment. Excessive use of TV and laptops was widespread among adolescents, with different demographic and contextual variables associated according to the type of device used.

Perceived Quality of Life Is Related to a Healthy Lifestyle and Related Outcomes in Spanish Children and Adolescents: The Physical Activity, Sedentarism, and Obesity in Spanish Study

BACKGROUND

Maintaining a healthy lifestyle is crucial for safeguarding the well-being and quality of life perception, appropriate growth, and development of children and adolescents, while also mitigating the risk of future adult-onset diseases.

OBJECTIVE

To assess associations between perceived quality of life and healthy lifestyle and related outcomes in Spanish children and adolescents.

METHODS

Cross-sectional analysis of 8-16-year-old children and adolescents (n = 3534) were included in the nationwide study of Physical Activity, Sedentarism, and Obesity in Spanish Youth (PASOS). Data were collected through (1) questionnaires on health-related quality of life (HRQoL), healthy lifestyle outcomes (dietary intake, physical fitness, sleep, and screen time), and (2) anthropometric measurements for weight status assessment. Data were analysed by logistic regression, using the health-related quality of life (HRQoL) as the grouping variable.

RESULTS

Participants with a lower HRQoL were those with a lower adherence to the MedDiet and lower achievement of the recommended daily intake of fruit and vegetables. They were also less likely to follow the recommendations for screen time and sleep (with the exception of the weekend) compared to participants with a higher HRQoL. Participants with a lower HRQoL showed a lower healthy weight status and poorer physical fitness than those with a higher HRQoL.

CONCLUSIONS

Healthy eating habits, healthy weight status (normal weight), appropriate sleep time, physical fitness, and limited screen time play a crucial role in the perceived quality of life in children and adolescents.

Association between healthy lifestyle factors and health-related quality of life among Chinese adolescents: the moderating role of gender

BACKGROUND

To examine the associations of the independent and combined healthy lifestyle factors with health-related quality of life (HRQOL) in adolescents, and to test the moderating role of gender.

METHODS

This cross-sectional study included 5125 adolescents aged between 11 and 20 years. They provided self-reported data on six healthy lifestyle factors, including never smoking, never drinking, good sleep quality, sufficient sleep duration, appropriate Internet use, and adequate physical activity. Adolescents' HRQOL was evaluated using the Pediatric Quality of Life Inventory version 4.0. Linear regression models were conducted to explore the association of individual and combined healthy lifestyle factors with adolescents' HRQOL. We further performed stratified analyses and likelihood ratio test to explore the moderating role of gender in these associations.

RESULTS

Of the included adolescents, the proportions with 0-2, 3, 4, and 5-6 healthy lifestyle factors were 13.6%, 26.4%, 44.3%, and 15.7%, respectively. Compared to adolescents with composite healthy lifestyle scores of 0-2, those with scores of 3, 4, or 5-6 had significantly higher HRQOL scores across all dimensions, summary scales, and total scale in both unadjusted and adjusted models. Specifically, adolescents with 5-6 healthy lifestyle factors had a total scale score that was 19.03 (95%CI: 17.76 to 20.30) points higher than their counterparts who only had 0-2 healthy lifestyle factors. Significant dose-response patterns were also observed in aforementioned associations. Gender was a significant moderator in the associations between composite healthy lifestyle groups and HRQOL scores, except for the social functioning dimension.

CONCLUSIONS

Our results confirmed that combined healthy lifestyle factors were associated with improved HRQOL among adolescents, with a stronger association observed in girls. These findings underscore the necessity for education and healthcare authorities to design health-promoting strategies that encourage multiple healthy lifestyle factors in adolescents, with the objective of enhancing their overall health outcomes.

The individual and combined associations of health behaviours with health-related quality of life amongst junior high school students in China

Objectives

This study aimed to investigate the individual and joint associations of sedentary behaviour, physical activity (PA), sleep and breakfast eating on health-related quality of life (HRQoL) amongst Chinese junior high school students.

Methods

Data were from 783 junior high school students who participated in a health behaviour and health survey in Jining city of Shandong province of China. HRQoL was measured by the EuroQol five-dimensional questionnaire, youth version (EQ-5D-Y). Multivariable logistic and linear regressions were applied to examine the associations between health behaviours and HRQoL.

Results

Multivariable regression analyses showed that using a computer ≥ 2 h a day (vs. < 2 h/day) is associated with increased likelihood of having health problems in the three EQ-D-Y dimensions, including walking, looking after self and doing usual activities. Lower PA is associated with more problems in feeling worried, sad or unhappy, and with a lower visual analogue scale (VAS) score. Students who had insufficient sleep time (e.g., <7 h/day), and skipped eating breakfast were more likely to experience lower HRQoL in the dimensions of having pain or discomfort, and feeling worried, sad or unhappy, and a lower VAS score than those students who had longer sleep time and no breakfast skipping. Students who reported having the combined ≥ 2 unhealthy behaviours relative to the peers with 0-1 unhealthy behaviours were more likely to have lower HRQoL.

Conclusion

The findings in the present study underline the importance of promoting healthy behaviours in order to improve HRQoL amongst Chinese junior high school students.

Sports activity limitation during the COVID-19 pandemic in young Italian athletes: impact on mental health in children, adolescents, and young adults

Introduction

The closure of sports centres was implemented as a preventive measure to mitigate the transmission of SARS-CoV-2. Given the observed global decline in physical activity and concurrent rise in sedentary behaviour, even among younger age groups, a retrospective cross-sectional study was undertaken to evaluate the effects of this measure on mental health in children, adolescents, and young adults during the initial phases of the COVID-19 pandemic.

Methods

A total of 1,717 non-professional athletes (age range: 6-25; 53.9% males, 44.6% females) completed an online questionnaire including widely used and validated measures for mental health assessment (SDQ and PGWB-S) and questions regarding sociodemographic characteristics (such as gender), physical activity, and screen time. The association between mental health and sociodemographic characteristics, physical activity, and screen time was evaluated by using univariate and multivariable logistic regression models.

Results

In children and adolescents, the incidence of psychological difficulties was associated with not being physically active (OR = 1.49; 95% CI: 1.09, 2.07; p = 0.015). Engaging in physical activity during the period of closures, particularly if more than twice a week, was significantly associated with less psychological difficulties for children/adolescents (OR = 0.54; 95% CI: 0.35, 0.82; p = 0.004) and psychological symptoms (i.e., psychological well-being lower than the median) for youth/young adults (OR = 0.25; 95% CI: 0.14, 0.45; p < 0.001). More psychological difficulties were also found in males for children and adolescents (OR = 1.37; 95% CI: 1.06, 1.79; p = 0.018). However, young adult males showed less psychological symptoms than females (OR = 0.35; 95% CI: 0.22, 0.55; p = 0.001). Additionally, a greater amount of screen time was associated with a higher incidence of psychological symptoms in the whole sample.

Conclusions

Our results confirm the positive impact of physical activity on mental health during the COVID-19 pandemic among younger age groups. They also provide valuable insights into the risk-benefit relationship of interrupting sports activities as a preventive measure for infectious diseases.

Body size, form, composition, and a healthy lifestyle associates with health-related quality of life among Portuguese children

OBJECTIVES

This study aimed to describe the relationship between body size, form, and composition, and children's lifestyle on health-related quality of life (HRQoL).

METHODS

This cross-sectional study comprised 1333 children (9.05 ± 0.75 years; 683 females) living in mainland Portugal. Objective anthropometric measures were collected. Parents answered a standardized questionnaire related with children's lifestyle (e.g., sport participation, screen- and sleep-time) and family socioeconomic status (e.g., parental education). HRQoL was measured using the Portuguese version of the KIDSCREEN-27. Scores were categorized into low and high using a sex-specific normative cut-off from European children. A healthier score was created including positive scores for body weight, abdominal obesity, sport participation, sleep- and screen-time.

RESULTS

Body size, form and composition were correlated with children's physical wellbeing. However, sex differences were found in which parameters were associated with wellbeing. Among boys, the body mass index, waist circumference, waist-to-height ratio, subscapular and suprailiac skinfold were most correlated with wellbeing, while waist circumference and subscapular skinfold showed the strongest correlations for girls. Sleep duration and sport participation revealed a significant relationship with girls' HRQoL. A logistic regression analysis (adjusted for parental education) revealed that boys scoring 4 or 5 in the healthier index had an increased likelihood of high HRQoL level compared to those fulfilling none.

CONCLUSIONS

Future programs aimed at reducing obesity, particularly central obesity, and incorporating multiple health indicators and behaviors, such as sport participation and sleep duration may help improve children's health and wellbeing.

Mental Health and Health-Related Quality of Life of Children and Youth during the First Year of the COVID-19 Pandemic: Results from a Cross-Sectional Survey in Saskatchewan, Canada

For children and youth, the COVID-19 pandemic surfaced at a critical time in their development. Children have experienced extended disruptions to routines including in-person schooling, physical activities, and social interactions-things that bring meaning and structure to their daily lives. We estimated the prevalence of anxiety and depression symptoms of children and youth and their experiences of health-related quality of life (HRQoL), during the first year of the pandemic, and identified factors related to these outcomes. Further, we examined these effects among ethnocultural minority families. We conducted an online survey (March-July 2021) with 510 children and youth aged 8-18 years and their parents/caregivers. The sample was representative of the targeted population. We modelled the relationship between anxiety, depression (measured using the Revised Child Anxiety and Depression Scale), HRQoL (measured using KIDSCREEN-10), and sociodemographic, behavioural, and COVID-19-contributing factors using binary logistic regression. A priori-selected moderating effects of sociodemographic characteristics and self-identified ethnocultural minority groups on the outcomes were tested. The point-in-time prevalence of medium-to-high anxiety symptoms and depression symptoms was 10.19% and 9.26%, respectively. Almost half (49.15%) reported low-to-moderate HRQoL. Children reporting medium-to-high anxiety symptoms, depression symptoms, and low-to-moderate HRQoL were more likely to be aged 8-11 years, 16-18 years, ethnocultural minority participants, living in rural/urban areas, having good/fair MH before COVID-19, experiencing household conflicts, having less physical activity, and having ≥3 h of recreational screen time. Those who had more people living at home and ≥8 h of sleep reported low anxiety and depression symptoms. Ethnocultural minority 16-18-year-olds were more likely to report low-to-moderate HRQoL, compared to 12-15-year-olds. Additionally, 8-11-year-olds, 16-18-year-olds with immigrant parents, and 16-18-year-olds with Canadian-born parents were more likely to report low-moderate HRQoL, compared to 12-15-year-olds. Children and youth MH and HRQoL were impacted during the pandemic. Adverse MH outcomes were evident among ethnocultural minority families. Our results reveal the need to prioritize children's MH and to build equity-driven, targeted interventions.

Systematic Review of the Psychometric Performance of Generic Childhood Multi-attribute Utility Instruments

BACKGROUND

Childhood multi-attribute utility instruments (MAUIs) can be used to measure health utilities in children (aged ≤ 18 years) for economic evaluation. Systematic review methods can generate a psychometric evidence base that informs their selection for application. Previous reviews focused on limited sets of MAUIs and psychometric properties, and only on evidence from studies that directly aimed to conduct psychometric assessments.

OBJECTIVE

This study aimed to conduct a systematic review of psychometric evidence for generic childhood MAUIs and to meet three objectives: (1) create a comprehensive catalogue of evaluated psychometric evidence; (2) identify psychometric evidence gaps; and (3) summarise the psychometric assessment methods and performance by property.

METHODS

A review protocol was registered with the Prospective Register of Systematic Reviews (PROSPERO; CRD42021295959); reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guideline. The searches covered seven academic databases, and included studies that provided psychometric evidence for one or more of the following generic childhood MAUIs designed to be accompanied by a preference-based value set (any language version): 16D, 17D, AHUM, AQoL-6D, CH-6D, CHSCS-PS, CHU9D, EQ-5D-Y-3L, EQ-5D-Y-5L, HUI2, HUI3, IQI, QWB, and TANDI; used data derived from general and/or clinical childhood populations and from children and/or proxy respondents; and were published in English. The review included 'direct studies' that aimed to assess psychometric properties and 'indirect studies' that generated psychometric evidence without this explicit aim. Eighteen properties were evaluated using a four-part criteria rating developed from established standards in the literature. Data syntheses identified psychometric evidence gaps and summarised the psychometric assessment methods/results by property.

RESULTS

Overall, 372 studies were included, generating a catalogue of 2153 criteria rating outputs across 14 instruments covering all properties except predictive validity. The number of outputs varied markedly by instrument and property, ranging from 1 for IQI to 623 for HUI3, and from zero for predictive validity to 500 for known-group validity. The more recently developed instruments targeting preschool children (CHSCS-PS, IQI, TANDI) have greater evidence gaps (lack of any evidence) than longer established instruments such as EQ-5D-Y, HUI2/3, and CHU9D. The gaps were prominent for reliability (test-retest, inter-proxy-rater, inter-modal, internal consistency) and proxy-child agreement. The inclusion of indirect studies (n = 209 studies; n = 900 outputs) increased the number of properties with at least one output of acceptable performance. Common methodological issues in psychometric assessment were identified, e.g., lack of reference measures to help interpret associations and changes. No instrument consistently outperformed others across all properties.

CONCLUSION

This review provides comprehensive evidence on the psychometric performance of generic childhood MAUIs. It assists analysts involved in cost-effectiveness-based evaluation to select instruments based on the application-specific minimum standards of scientific rigour. The identified evidence gaps and methodological issues also motivate and inform future psychometric studies and their methods, particularly those assessing reliability, proxy-child agreement, and MAUIs targeting preschool children.

Elementary School-Aged Children's and Parents' Report of Health-Related Quality of Life and Relationships with Lifestyle Measures: A Cross-Sectional Study

Supporting a child's health-promoting lifestyle is an investment in their future health and health-related quality of life (HRQoL). Particularly children with overweight and obesity may be at an increased risk of a poor HRQoL. Currently, a comprehensive evaluation of lifestyle factors and age in relation to HRQoL in healthy children and, further, separate child and parental proxy-reports of HRQoL are lacking. The aims of this cross-sectional study in Finland are to compare healthy elementary school-aged children's and parents' reports of the child's HRQoL, and to view them in relation to lifestyle markers. The HRQoL was measured with Pediatric Quality of Life Inventory^TM 4.0, and the following lifestyle markers: leisure-time physical activity as MET, diet quality via a validated index (ES-CIDQ), sleeping time and screen time by questionnaires. Furthermore, age and BMI were recorded. Data were obtained from 270 primary school-aged children (6-13 years). Female gender, the child's older age (8-13 years), high physical activity level and less screen time were strong predictors of a higher HRQoL in both the child's and parental proxy-reports. Means to promote healthy lifestyles should be particularly targeted to young children, especially boys, and new ways to promote physical activity and other forms of free-time activities should be sought.

Effect of Sleep Changes on Health-Related Quality of Life in Healthy Children: A Secondary Analysis of the DREAM Crossover Trial

IMPORTANCE

Little is known regarding the effect of poor sleep on health-related quality of life (HRQOL) in healthy children.

OBJECTIVE

To determine the effect of induced mild sleep deprivation on HRQOL in children without major sleep issues.

DESIGN, SETTING, AND PARTICIPANTS

This prespecified secondary analysis focused on HRQOL, a secondary outcome of the Daily Rest, Eating, and Activity Monitoring (DREAM) randomized crossover trial of children who underwent alternating weeks of sleep restriction and sleep extension and a 1-week washout in between. The DREAM trial intervention was administered at participants' homes between October 2018 and March 2020. Participants were 100 children aged 8 to 12 years who lived in Dunedin, New Zealand; had no underlying medical conditions; and had parent- or guardian-reported normal sleep (8-11 hours/night). Data were analyzed between July 4 and September 1, 2022.

INTERVENTIONS

Bedtimes were manipulated to be 1 hour later (sleep restriction) and 1 hour earlier (sleep extension) than usual for 1 week each. Wake times were unchanged.

MAIN OUTCOMES AND MEASURES

All outcome measures were assessed during both intervention weeks. Sleep timing and duration were assessed using 7-night actigraphy. Children and parents rated the child's sleep disturbances (night) and impairment (day) using the 8-item Pediatric Sleep Disturbance and 8-item Sleep-Related Impairment scales of the Patient-Reported Outcomes Measurement Information System questionnaire. Child-reported HRQOL was assessed using the 27-item KIDSCREEN questionnaire with 5 subscale scores and a total score. Both questionnaires assessed the past 7 days at the end of each intervention week. Data were presented as mean differences and 95% CIs between the sleep restriction and extension weeks and were analyzed using intention to treat and an a priori difference in sleep of at least 30 minutes per night.

RESULTS

The final sample comprised 100 children (52 girls [52%]; mean [SD] age, 10.3 [1.4] years). During the sleep restriction week, children went to sleep 64 (95% CI, 58-70) minutes later, and sleep offset (wake time) was 18 (95% CI, 13-24) minutes later, meaning that children received 39 (95% CI, 32-46) minutes less of total sleep per night compared with the sleep extension week in which the total sleep time was 71 (95% CI, 64-78) minutes less in the per-protocol sample analysis. Both parents and children reported significantly less sleep disturbance at night but greater sleep impairment during the day with sleep restriction. Significant standardized reductions in physical well-being (standardized mean difference [SMD], -0.28; 95% CI, -0.49 to -0.08), coping in a school environment (SMD, -0.26; 95% CI, -0.42 to -0.09), and total HRQOL score (SMD, -0.21; 95% CI, -0.34 to -0.08) were reported by children during sleep restriction, with an additional reduction in social and peer support (SMD, -0.24; 95% CI, -0.47 to -0.01) in the per-protocol sample analysis.

CONCLUSIONS AND RELEVANCE

Results of this secondary analysis of the DREAM trial indicated that even 39 minutes less of sleep per night for 1 week significantly reduced several facets of HRQOL in children. This finding shows that ensuring children receive sufficient good-quality sleep is an important child health issue.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12618001671257.

Results from the Hong Kong's 2022 report card on physical activity for children and adolescents

Background/objective

This paper aimed to summarize the findings of the third (2022) Active Healthy Kids Hong Kong Report Card on Physical Activity for Children and Adolescents and evaluate the secular trends of physical activity related indicators.

Methods

Five behavioral indicators (Overall Physical Activity, Organized Sport and Physical Activity, Active Play, Active Transportation, and Sedentary Behavior), three outcome indicators (Physical Fitness, Sleep, and Obesity) and four sources of influence indicators (Family and Peers, School, Community and Environment, and Government) were assigned a letter grade (ranging from A+ to F or incomplete) based on the best available evidence following a harmonized approach developed by the Active Healthy Kids Global Alliance. Data sources included published journal articles, government reports, manual searches, and personal contacts; and consisted of both pre-COVID-19 and after-COVID-19 evidence.

Results

Grades for Overall Physical Activity (D−∗∗) and Sedentary Behavior (D) deteriorated compared to the 2018 Report Card. The other three behavioral indicators, Organized Sport and Physical Activity, Active Play, and Active Transportation, were assigned B−, D, and B+, respectively. Physical Fitness (D), Sleep (C−), and Obesity (D−) obtained the same grades as in the 2018 Report Card. School (B) and Government (C+) grades slightly improved, while Community and Environment grade (B) was stable. Family and Peers was not graded due to insufficient evidence.

Conclusions

Despite slight improvements in influence indicators, physical activity and sedentary behavior have changed unfavorably for children and adolescents in Hong Kong. Strategic investments are needed to improve adoption and implementation of effective interventions.

Associations of excessive screen time and early screen exposure with health-related quality of life and behavioral problems among children attending preschools

BACKGROUND

Both excessive screen time and early screen exposure have been linked to children's health outcomes, but few studies considered these two exposures simultaneously. The aim of this study was to explore the independent and interactive associations of excessive screen time and early screen exposure with health-related quality of life (HRQOL) and behavioral problems among Chinese children attending preschools.

METHODS

A cross-sectional study of 4985 children aged between 3 and 6 years was conducted in Chengdu, China. Each parent has finished an online questionnaire regarding their children's screen use, HRQOL, and behavioral problems. Children with screen time over 1 h/day were considered as having excessive screen time. Early screen exposure was defined if the children had started using screen-based media before the age of 2 years. HRQOL was assessed by the Pediatric Quality of Life Inventory version 4.0 (PedsQL 4.0), while behavioral problems were confirmed with the 48-item Conners' Parent Rating Scale (CPRS-48).

RESULTS

Of the 4985 children (2593 boys and 2392 girls) included, the mean age was 4.6 (SD: 1.0) years. After adjustment for confounders and early screen exposure, excessive screen time was significantly associated with worse HRQOL scores in all dimensions and summary scales, as well as each type of behavioral problems (all p values < 0.05). We also found that compared to children with later initiation of screen exposure, those with screen use before the age of 2 years had significantly lower emotional functioning score (β: - 2.13, 95%CI: - 3.17, - 1.09) and psychosocial health summary score (β: - 0.82, 95%CI: - 1.54, - 0.10) of HRQOL, as well as higher risks of conduct problems, learning problems, psychosomatic problems, impulsive-hyperactive, and hyperactivity index, which were independent of excessive screen use. Furthermore, there were significant interactive effects of excessive screen time and early screen exposure on emotional functioning domain of HRQOL scores and conduct problems.

CONCLUSION

Excessive screen time and early screen exposure are two independent and interactive factors to children's HRQOL and behavioral problems. Our findings support current guidelines to limit screen exposure in children. Appropriate screen use may represent an important intervention target to improve children's HRQOL and reduce their behavioral problems.

The Associations between 24-Hour Movement Behaviours and Quality of Life in Preschoolers: A Compositional Analysis of Cross-Sectional Data from 2018-2021

Studies show that the quality of life (QoL) of preschoolers is closely related to physical activity (PA), sedentary behaviour (SB), and sleep (SL). Yet many researchers looked at these 24-h movement behaviours as behaviours that are independent of one another when examining the association of QoL with these behaviours. The main purpose of the present study was to describe the temporal trends in PA, SB, and SL in preschoolers and the concomitant association with QoL of children. Annual cross-sectional data on QoL and 24-h movement behaviours of 8045 Singaporean preschoolers were collected from 2018 to 2021. Compositional analysis, linear regression, and isotemporal replacement approaches were used to examine changes in PA, SB, and SL from 2018-2021 and how these changes were associated with QoL. Temporal trends in movement behaviours showed that PA and SL decreased after 2020. During 2018-2021, the association of PA and QoL in preschoolers was characterised by a 'U' curve (βPA-2018 = 3.06, p < 0.001; βPA-2019 = 1.43, p < 0.05; βPA-2020 = -0.43, p > 0.05; βPA-2021 = 2.82, p < 0.001), while SL and QoL were characterised by an inverted 'U' curve (βSL-2018 = -2.39, p < 0.001; βSL-2019 = -0.27, p > 0.05; βSL-2020 = 2.00, p < 0.01; βSL-2021 = -0.21, p > 0.05). SB was significantly and negatively associated with QoL after 2020, with 2020 identified as the inflection point for the change in SB (βSB-2018 = 0.67, p > 0.05; βSB-2019 = -1.16, p > 0.05; βSB-2020 = -1.56, p < 0.01; βSB-2021 = -2.61, p < 0.01). Using a time re-allocation technique to treat the 2021 data, reallocating time from SB to PA or to SL predicted improvements in QoL of preschoolers (Pall < 0.05). The study provided useful information on the temporal trends in PA, SB, SL, and QoL of preschoolers over four years. Additionally, these data provided insights into how changes in QoL are predicted by changes in duration in the 24-h movement behaviours.

Under contract and in good health: a multigroup cross-lagged panel model of time use and health-related quality of life in working-age men and women

Background

Self-reported time-use in relation to health-related quality of life (HRQoL) has been widely studied, yet less is known about the directionality of the association and how it compares across genders when controlling for sociodemographic confounders.

Methods

This study focused on the working population of the most recent waves (2013–2018) of the Core-Study of the German Socio-Economic Panel (N = 30,518, 46.70% female, M = 39.24 years). It examined the relationship between three time-use categories (contracted, committed, & leisure time) and HRQoL (self-rated health & life satisfaction) in men and women via multigroup fixed effects cross-lagged panel models. The models controlled for sociodemographic background (age, household income, number of children living in household, employment status, education, & marital status), which was associated with time-use and psychosocial health in previous research.

Results

Contracted time showed consistent positive relationships with HRQoL across genders while associations with the other types of time use differed significantly between men and women and across indicators of HRQoL.

Conclusions

The way we spend our time directly predicts our health perceptions, but in the same vein our health also predicts how we can spend our time. Contracted time in particular was associated with positive HRQoL, across genders, and beyond sociodemographic predictors, highlighting the important role of employment in health, for men and women alike. The impact of commitments beyond contracted time-use—like household chores and childcare—however, continues to affect mainly women, which ultimately reflects in poorer health outcomes.

Distinguishing the Associations Between Evening Screen Time and Sleep Quality Among Different Age Groups: A Population-Based Cross-Sectional Study

OBJECTIVE

The age differences in the association between screen time and sleep problems have been implied in many studies, and this study aims to distinguish the associations between evening screen time and sleep quality among different age groups.

METHODS

This is a population-based, cross-sectional study among community residents aged ≥18 years in China. A total of 21,376 valid questionnaires were analyzed. Sleep quality was measured by the Pittsburgh Sleep Quality Index. Averaged evening screen time (AEST), sociodemographic information, and health-related behaviors were also evaluated in this study.

RESULTS

In the 18-to-34-year age group, compared with people without AEST, ≤1 h/day (β = 0.34, p < 0.05) and >3 h/day (β = 1.05, p < 0.001) of AEST were significantly associated with poor sleep quality, and a reverse S-shaped relationship for this association was shown. In the 35-to-49-year and 50-to-64-year age groups, ≤1 h/day (β = 0.43 and 0.36, both p < 0.001), ≤2 h/day (β = 0.43 and 0.31, p < 0.001 and p < 0.01), ≤3 h/day (β = 0.62 and 0.61, both p < 0.001), and >3 h/day (β = 1.55 and 1.88, both p < 0.001) of AEST were positively associated with poor sleep quality. In the 65-year-and-older age group, a J-shaped relationship was found, and ≤3 h/day (β = 0.82, p < 0.001) and >3 h/day (β = 1.84, p < 0.001) of AEST were associated with poor sleep quality.

CONCLUSION

Associations between AEST and sleep quality among different age groups are different. In the 18-to-34-year and 65-year-and-older age groups, acceptable AEST is not related to sleep quality. In the 35-to-49-year and 50-to-64-year age groups, AEST was harmful to sleep quality.

The Role of Physical Activity in the Relationship between Satisfaction with Life and Health-Related Quality of Life in School-Age Adolescents

(1) Background: Adolescence is a critical stage in the development of healthy habits. In this regard, physical activity has emerged as a useful tool to improve satisfaction with life and health-related quality of life in adolescents. Therefore, the aim of the present study was to examine the mediating role of physical activity in the relationship between satisfaction with life and health-related quality of life in adolescent boys and girls. Also, we aimed to investigate the differences between sexes in the HRQoL, physical activity level, and satisfaction with life. (2) Methods: A total of 297 adolescents, ranging in age from 11 to 12 years (11.46 ± 1.63), participated in this cross-sectional study. The Satisfaction with life scale, Physical activity Questionnaire for Adolescents and the KIDSCREEN-10 questionnaires were employed. (3) Results: The estimated indirect effect showed that physical activity level was a mediator of the positive effect of satisfaction with life on health-related quality of life (β = 0.105, 95% CI = 0.031; 0.202). However, the index of moderated mediation showed that sex is not a significant moderator of the mediating role of physical activity in the relationship between satisfaction with life and HRQoL (β = -0.033, 95% CI = -0.023, 0.136). Furthermore, significant differences in satisfaction with life were found, with girls manifesting lower values (p-value = 0.026). (4) Conclusion: This study shows the importance of physical activity during adolescence and the association of this behavior with the health-related quality of life of adolescents.