The effect of childhood depression trajectories on sugar-sweetened beverage habit trajectories in adolescence: Exploring sleep problems as a mediator.

Although depression has been linked to the habit of consuming sugar-sweetened beverages (SSBs), little is known about their long-term relationships and the mediating role of sleep problems. This study examines the associations between childhood depressive symptoms trajectories and adolescent SSB-habit trajectories and whether these associations were mediated by sleep problems. Data came from 1560 adolescents participating in a longitudinal study across grades 1 through 12 in northern Taiwan. Group-based trajectory modeling was used to identify development of childhood depressive symptoms and an SSB habit in adolescence. Multinomial logistic regression was conducted to examine the influence of childhood depressive symptoms and adolescent SSB habit. Mediation analysis was conducted to test whether sleep problems mediated the associations examined. Four distinct trajectories of childhood depressive symptoms were identified: low-stable (30.79%), moderate-stable (42.32%), increasing (12.29%), and high-stable (11.60%). Three distinct trajectories of SSB habit in adolescence were identified: low-stable (44.32%), increasing (15.02%), and high-stable (40.65%). Children who had moderate-stable (aOR = 1.35; CI: 1.04-1.77), high-stable (aOR = 2.01; CI: 1.28-3.15), or increasing (aOR = 1.97; CI: 1.26-3.06) trajectories of depressive symptoms relative to those in the low-stable group were significantly more likely to belong to the high-stable trajectory of SSBs than to the low-stable SSBs group. The Z-mediation test showed that sleep problems significantly mediated the associations between trajectories of childhood depressive symptoms and trajectories of SSBs during adolescence (all p < 0.05). Childhood depressive symptoms conferred risks for adolescent SSB habits; and the effects were seen, in part, through increasing sleep problems.

Associations between social loneliness trajectories and chronotype among adolescents.

Late chronotype during adolescence is a critical risk factor for poor physical and mental health among adolescents. While social loneliness is confirmed to negatively influence sleep behaviors, the long-term effect of social loneliness on chronotype remains unknown. This study aims to investigate whether social loneliness trajectories from middle childhood to adolescence are associated with chronotype in late adolescence and examine the potential sex differences in these associations. Data were obtained from 2398 adolescents who participated in the Child and Adolescent Behaviors in Long-Term Evolution project. Chronotype was calculated as the midpoint of sleep on free days adjusted for sleep debt. Group-based trajectory modeling and multiple linear regression were employed to establish social loneliness trajectories and determine their associations with chronotype. Social loneliness trajectories were significantly associated with chronotype and varied by sex. Specifically, boys following a high-decreasing trajectory had earlier chronotype during late adolescence than did those following a low-decreasing trajectory (B = - 0.07; p < 0.05). By contrast, girls following a low-to-moderate-increasing trajectory exhibited later chronotype than did those following a low-stable trajectory (B = 0.07; p < 0.01). Social loneliness trajectories, especially those displaying significant fluctuations over time, are critical indicators influencing chronotype among adolescents. Furthermore, these trajectories and their associations with chronotype display sex differences. These findings highlight the need for early interventions for psychological factors such as social loneliness to ensure that the late chronotype can be prevented. In addition, sex variations must be considered.

Parents' right strategy on preventing youngsters' recent suicidal ideation: a 13-year prospective cohort study.

BACKGROUND: Suicide remains the second leading cause of death among youths. Family-related factors are considered important determinants of children's suicidal ideation, whereas their short-/long-term influence is seldom quantified. AIMS: We aim to confirm the simultaneous/lagged effects of family-related factors on the occurrence of recent suicidal ideation from childhood to young adulthood (aged from 10 to 22 years old). METHOD: Data were derived from a longitudinal prospective cohort study. Participants included 2065 students who were followed up for 13 years. Generalized estimating equations were used to clarify the influential effects of family-related factors on suicidal ideation during the past month. RESULTS: The peak of the rate of recent suicidal ideation arrived during junior high school years. Family interaction, family support, family involvement, and parental punishment had simultaneous effects on recent suicidal ideation. Family involvement, parental conflict, and psychological control had lagged and lasting effects on suicidal ideation. Notably, the lasting protective effects of family involvement were more obvious than simultaneous effects. CONCLUSIONS: Providing parents with sustained support and education to improve their "positive parenting literacy" can help with their children's mental health development. This is especially the case during COVID-19 quarantine periods when families spend the most time together at home.

Sex differences in the trajectories of and factors related to extracurricular sport participation and exercise: a cohort study spanning 13 years.

BACKGROUND: Extracurricular sport participation and exercise (ESPE) refers to regular exercise/sport participation in addition to the physical education in school among a school-aged population. Rather than general physical activity, ESPE is typically deliberately initiated and presents an efficient target for interventions. However, compared to physical activity, relatively few studies have investigated sex differences in the development of and factors associated with ESPE using a person-centered approach. This study aimed to examine the latent trajectories of ESPE from childhood to emerging adulthood across sexes, and to identify the associated sex-specific individual (i.e., body mass index, body dissatisfaction, stress, and screen behavior) and parental (i.e., parental exercise and parental screen behavior) factors. METHODS: This study used data from part of the Child and Adolescent Behavior in Long-term Evolution (CABLE) project, which comprised 2072 fourth graders (aged 9 years) in Northern Taiwan followed annually from 2001 to 2013 (13 waves). Repeated-measures latent class analysis was used to identify the trajectories of ESPE for males and females, respectively. Multinomial logistic regression was further used to identify sex-specific factors related to ESPE. RESULTS: Four trajectories of ESPE were identified for males and females. For males, these trajectories were Rarely-to-Never (20%), Often-to-Rarely (32%), Always-to-Never (21%), and Always (27%). For females, these trajectories were Rarely-to-Never (34%), Rarely (23%), Always-to-Rarely (33%), and Always (10%). We observed that the developmental patterns of ESPE varied by sex such that there was an earlier decline in the trajectories of ESPE in females than in males and that, compared with males, fewer females maintained exercise habits in young adulthood. Furthermore, we found several sex-specific factors related to ESPE, namely, stress, BMI, and parental exercise. Body dissatisfaction and individual screen behavior were associated with trajectories of ESPE for both sexes. CONCLUSIONS: We found distinct trajectories of ESPE from childhood to emerging adulthood for both sexes. The trajectories of ESPE for males and females, however, differ in terms of patterns and associated factors. Our findings suggest that efforts to increase ESPE should be initiated early, and may be made more effective by considering sex differences.

A population-based study of the influence of socioeconomic status on prostate cancer diagnosis in Taiwan.

BACKGROUND: Disparities in prostate cancer (PCa) outcomes and their links to socioeconomic status (SES) have been intensively studied. A relatively low incidence rate and a high proportion of late-stage diagnosis have been documented in studies of Asian populations. For the past 20 years, the trend in the growth of PCa cases in Taiwan was opposite to that of Western countries. However, there is a striking paucity of local studies on these important issues. To mitigate this gap in knowledge, we exploited two population databases to investigate the impact of SES on PCa incidence rate and stage at diagnosis. Particularly, we sought to explore the discriminating capabilities of various indexes of SES on two diagnostic outcome indicators. METHOD: We conducted a population-based, follow-up, observational study. Data of study populations and newly diagnosed PCa cases between 2011 and 2013 were collected from the National Health Insurance Research Database and the Taiwan Cancer Registry. We retrieved 50-79 old male subjects who were classified as government employee, enterprise employee, or labor class. People with a diagnosis of any type of cancer before January 1, 2011, were excluded. The influences of four independent variables, i.e., age, beneficiary's insurance status, occupation and income, were analyzed. We used Cox proportional hazard models to calculate the hazard ratios of PCa and used logistic regression models to analyze the odds ratios (ORs) of late-stage PCa diagnosis. RESULTS: The low crude PCa incidence rate (112 per 100,000 person-years) and the high percentage of late-stage presentation (44%) were similar to those found in previous studies of old Asian men. Unsurprisingly, age was consistently revealed to be the most determinant factor in PCa diagnosis, while the insurance status of the beneficiaries showed no significant difference. Significant socioeconomic disparities in PCa diagnosis were demonstrated by occupation and income indexes, individually or in combination. However, occupation and income showed varied capabilities in discriminating disparities between different outcome indicators. CONCLUSION: Our study supported the findings of extant works showing that advantaged populations have a higher PCa incidence rate and a lower percentage of late-stage diagnosis. The discriminating capabilities of health disparity by occupation and/or income were contingent on the choice of health outcome indicators. The relatively high percentage of late-stage presentation is a critical public health challenge, and a tailored coping strategy is urgently needed. For more effective health policy-making, local socioeconomic effects on the other outcome indicators of PCa, such as incidence to mortality ratio, warrant further investigation.

Transitions in sleep problems from late adolescence to young adulthood: A longitudinal analysis of the effects of peer victimization.

Adolescence is a developmental period with high vulnerability to sleep problems. However, research identifying distinct patterns and underlying determinants of sleep problems is scarce. This study investigated discrete subgroups of, changes in, and stability of sleep problems. We also examined whether peer victimization influenced sleep problem subgroups and transitions in patterns of sleep problems from late adolescence to young adulthood. Sex differences in the effects of peer victimization were also explored. In total, 1,455 male and 1,399 female adolescents from northern Taiwan participated in this longitudinal study. Latent transition analysis was used to examine changes in patterns of sleep problems and the effects of peer victimization on these changes. We identified three subgroups of sleep problems in males and two in females, and found that there was a certain level of instability in patterns of sleep problems during the study period. For both sexes, those with greater increases in peer victimization over time were more likely to change from being a good sleeper to a poor sleeper. The effects of peer victimization on baseline status of sleep problems, however, was only significant for males, with those exposed to higher levels of peer victimization more likely to be poor sleepers at baseline. Our findings reveal an important role of peer victimization in predicting transitions in patterns of sleep problems. Intervention programs aimed at decreasing peer victimization may help reduce the development and escalation of sleep problems among adolescents, especially in males.

Reciprocal relationship between unhealthy eating behaviours and depressive symptoms from childhood to adolescence: 10-year follow-up of the Child and Adolescent Behaviors in Long-Term Evolution study.

OBJECTIVE: To investigate the reciprocal relationship between unhealthy eating behaviours and depressive symptoms from childhood to adolescence. DESIGN: Unhealthy eating behaviours were measured by the frequencies of eating foods with excess salt, sugar or fat in the past week. Depressive symptoms in the past two weeks were measured using a seven-item scale. Hierarchical linear growth models were used to analyse longitudinal associations between unhealthy eating behaviours and depressive symptoms. Time-fixed variables (sex, parents' education level and household monthly income) and time-varying variables (parents' marital status, family activities, body weight, vegetable or fruit consumption, exercising and smoking) were controlled for. SETTING: The Child and Adolescent Behaviors in Long-Term Evolution study, which commenced in 2001 and has annual follow-up. SUBJECTS: Students (n 2630) followed from 2nd grade (8 years old in 2002) to 11th grade. RESULTS: The frequency of unhealthy eating behaviours in the previous year and the difference between the frequency in the previous and successive year were positively associated with the initiation and growth rate of depressive symptoms. Depressive symptoms in the previous year and the difference in depressive symptoms between the previous and successive year were positively associated with the initial state and growth rate of unhealthy eating behaviours. CONCLUSIONS: Our results suggest a reciprocal relationship between depressive symptoms and unhealthy eating behaviours. This relationship should be considered when developing programmes targeting depressive symptoms and unhealthy diet in children and adolescents.

The effects of social structure and social capital on changes in smoking status from 8th to 9th grade: results of the Child and Adolescent Behaviors in Long-term Evolution (CABLE) study.

OBJECTIVE: Social structure and social capital are important variables for public health strategies seeking to prevent smoking among adolescents. The purpose of this study was to examine the relationships between social structure, social capital and changes in smoking status from the 8th to 9th grade in Taiwan. METHODS: Data were obtained from the Child and Adolescent Behaviors in Long-term Evolution (CABLE) project. The study analyzed a final sample of 1937 students (50.7% female). RESULTS: Each layer of social structure was associated with a particular form of social capital. Students whose parents were married and living together had higher family social capital. After controlling for background variables, the social structure variable of friends who smoke was significantly associated with changes in smoking status. Students reporting more school attachment were less likely to start smoking. Students with higher parental supervision was associated with less chance of being a consistent smoker, whereas participation of social organization outside of school was associated with continued smoking. Attending school club was associated with higher probability of smoking cessation. CONCLUSION: Smoking prevention and intervention strategies aimed at junior high school students should be tailored to the particular form of social capital important for each type of smoking status.

Associations between social jetlag trajectories and body mass index among young adults.

STUDY OBJECTIVES: This study employed longitudinal data collected repeatedly from individuals over the course of several years to examine the trajectories of social jetlag from ages 11 to 22 years and their associations with subsequent body mass index (BMI). Potential sex differences were also investigated. METHODS: Data were obtained from two longitudinal studies conducted in Taiwan (N = 4287). Social jetlag was defined as ≥ 2 hours of absolute difference in sleep midpoint between weekdays and weekends. BMI was calculated using weight (kg)/height(m)2 and categorized as underweight (<18 kg/m2), normal weight (18 kg/m2 ≤ BMI < 24 kg/m2), overweight (24 kg/m2 ≤ BMI < 27 kg/m2), and obese (≥27 kg/m2). Group-based trajectory modeling and multinomial logistic regression were applied to investigate study objectives. RESULTS: Four distinct trajectories of social jetlag throughout the adolescent years were identified, with corresponding proportions as follows: low-stable (42%), moderate-decreasing (19%), low-increasing (22%), and chronic (17%) trajectories. Among males, the risk of being underweight (aOR, 1.96; 95% CI: 1.35 to 2.84) or obese (aOR, 1.40; 95% CI: 1.02 to 1.92) was higher in individuals with a low-increasing trajectory than in those with a low-stable trajectory. Among females, those with a low-increasing (aOR, 1.61; 95% CI: 1.02 to 2.54) or chronic (aOR, 2.04; 95% CI: 1.27 to 3.25) trajectory were at a higher risk of being obese relative to those with a low-stable trajectory. CONCLUSIONS: Addressing the development of increasing or chronic social jetlag during adolescence can help prevent abnormal BMI in young adulthood. Practitioners should consider sex differences in treatment or consultation.

Influence of stressors and possible pathways of onset of seventh graders' suicidal ideation in urban and rural areas in Taiwan.

BACKGROUND: Suicide is the second leading cause of death among young people in Taiwan. However, few studies have investigated children's suicidal ideation, and longitudinal studies are particularly rare. The purposes of this study were: (1) to describe the proportion of students with suicidal ideation in one month and incidence of suicidal ideation in the 7th graders (the first year of junior high school) living in urban and rural areas; (2) to realize the influence of perceived stressors on the onset of 7th graders' suicidal ideation; and (3) to explore possible pathways through which trigger factors and perceived stressors lead to suicidal ideation. METHODS: A total of 1,589 students were followed from grade 4 to grade 7. Logistic regression was then used to investigate the influence of perceived stressors on the onset of suicidal ideation in grade 7. Structural equation modeling was used to analyze possible pathways through which trigger factors led to increased pressure from certain stressors which in turn resulted in suicidal ideation. RESULTS: The proportion of students with suicidal ideation in one month was 2 to 3 times higher in both areas compared to that in elementary school. However, the incidence in the rural area showed a large increase from 10.2% and 9.5% in grades 5 and 6 to 15.5% in grade 7. Urban-rural difference was observed. Important stressors and pathways of suicidal ideation differ between urban and rural areas. CONCLUSIONS: This study showed that the influential stressors in urban and rural areas might be different. Thus, interventions focused on coping skills for regional specific stressors and trigger factors could be beneficial in the transition time.

Effects of Social Attachment on Experimental Drug Use From Childhood to Adolescence: An 11-Year Prospective Cohort Study.

Background: Drug use among adolescents are still crucial issues that endanger their lifetime health. Evidence concerning the interpersonal-related factors influencing youngsters' experimental drug use behavior, especially from longitudinal and school-based prospective cohort studies, is insufficient. We aimed to describe the annual incidence rate and mean annual incidence rate of experimental drug use from childhood to adolescence by education stage, clarify the risk in childhood and examine the longitudinal relationship between social attachment factors and experimental drug use. Materials and Methods: The data were derived from the 1st to 11th wave of the longitudinal study. In total, 1,106 respondents aged 19-20-year-old were followed up for 11 years (from 9 to 10-year-old) in Taiwan. A survival analysis was used to analyze the time-invarying/time-dependent effects of social attachment factors on experimental drug use. Results: The mean annual incidence rate of experimental drug use from childhood to adolescence was 6.8‰. The incidence increased over time and was the highest in the first year of university (19.3‰). Boys were more likely to use drugs than girls. A low degree of self-perceived likeability in childhood was a risk factor influencing experimental drug use. On average, a low degree of parental supervision and a high degree of family conflict were both influential risk factors. According to the time-dependent models, a high degree of parental supervision, a high degree of family support and a low degree of family conflict in the current year can protect children and adolescents from drug use, whereas a sustained low degree of parental supervision and a high degree of family conflict may promote students' experimental drug use. Conclusion: Parents should be informed and educated to avoid family conflict during childhood, maintain consistent supervision of their children's behavior, provide adequate family support, and pay attention to their children's interpersonal relationships in school. Teachers should focus on the social attachment status of their students while considering their attachments to their families and peers.

The incidence of experimental smoking in school children: an 8-year follow-up of the child and adolescent behaviors in long-term evolution (CABLE) study.

BACKGROUND: Studies have established that most regular adult smokers become addicted in their adolescent years. We investigated the incidence of and risk factors associated with initial experimental smoking among a group of school children who were followed for 8 years. METHODS: We used cohort data collected as part of the Child and Adolescent Behaviors in Long-term Evolution (CABLE) study, which selected nine elementary schools each from an urban area (Taipei City) and a rural area (Hsingchu county) in northern Taiwan. From 2002 to 2008, children were asked annually whether they had smoked in the previous year. An accelerated lifetime model with Weibull distribution was used to examine the factors associated with experimental smoking. RESULTS: In 2001, 2686 4th-graders participated in the study. For each year from 2002 to 2008, their incidences of trial smoking were 3.1%, 4.0%, 2.8%, 6.0%, 5.3%, 5.0% and 6.0%, respectively. There was an increase from 7th to 8th grade (6.0%). Children who were males, lived in rural areas, came from single-parent families, had parents who smoked, and had peers who smoked were more likely to try smoking earlier. The influence of parents and peers on experimental smoking demonstrated gradient effects. CONCLUSIONS: This study used a cohort to examine incidence and multiple influences, including individual factors, familial factors, and community factors, on experimental smoking in adolescents. The findings fit the social ecological model, highlighting the influences of family and friends. School and community attachment were associated with experimental smoking in teenagers.

Resilience buffers the effects of sleep problems on the trajectory of suicidal ideation from adolescence through young adulthood.

OBJECTIVES: To examine both the between-person and within-person effects of sleep problems on the trajectory of suicidal ideation from ages 14 to 22 and investigate whether resilience moderates the effects. Age and sex differences were explored in the main and interaction effects of sleep problems and resilience on suicidal ideation. METHODS: The study sample included 2491 adolescents (1260 males and 1231 females) who participated in a prospective study spanning 2009 through 2016 in northern Taiwan. Sex-stratified multilevel models were used to examine the between-person and within-person effects of sleep problems and the moderating effects of resilience on the trajectory of suicidal ideation in males and females. RESULTS: Across adolescents, higher levels of sleep problems contributed to an elevated risk of suicidal ideation for both sexes. Within individuals, a higher risk of suicidal ideation was observed when an adolescent's sleep problems exceeded their typical levels. The within-person effects of sleep problems were further determined to vary by age in males, with the effects gradually decreasing throughout late adolescence but increasing again in young adulthood. The buffering effects of resilience were only observed in females. The relationships between the within-person effects of sleep problems and suicidal ideation were only significant in female adolescents with low levels of resilience. CONCLUSIONS: Our findings extend the research by demonstrating both the between-person and within-person association between sleep problems and suicidal ideation. We further revealed age and sex differences in the within-person effects of sleep problems and the buffering effects of resilience. Prevention and intervention programs that target sleep problems could be tailored based on individuals' age, sex, and levels of resilience to prevent suicidal ideation.

The effects of family dysfunction trajectories during childhood and early adolescence on sleep quality during late adolescence: Resilience as a mediator.

RATIONALE: Sleep quality has been linked to several behavioral and psychological problems. No longitudinal study has examined the associations and underlying mechanisms between the trajectories of family characteristics and sleep quality in adolescents. OBJECTIVE: This study investigates the effects of heterogeneous trajectories of family dysfunction on sleep quality in adolescents and examines whether resilience mediates these associations. METHOD: Data came from 2280 adolescents participating in a longitudinal study across grades 2 through 11 in northern Taiwan. Group-based trajectory modeling was used to identify discrete developmental patterns of family dysfunction. Multiple linear regression was applied to examine the associations between family dysfunction trajectories and sleep quality. Mediation analysis was conducted to test whether resilience mediates the associations examined. RESULTS: Four distinct trajectories of family dysfunction were identified: low persistent (26%), escalating dysfunction (21%), moderate stable (25%), and high persistent (28%). Compared to adolescents in the low-persistent trajectory, those in the escalating-dysfunction, moderate-stable, and high-persistent trajectories had significant lower levels of sleep quality (B = -0.19, p < .001, B = -0.14, p < .01, and B = -0.13, p < .05, respectively). Resilience significantly mediated the effects of all family dysfunction trajectories (relative to the low-persistent trajectory) on sleep quality (95% bootstrap confidence intervals are -0.06 to -0.02, -0.05 to -0.02, and -0.08 to -0.03 for escalating-dysfunction, moderate-stable, and high-persistent trajectories, respectively). CONCLUSIONS: Family dysfunction conferred risks for poor sleep quality in adolescents and the negative effects, in part, were through decreasing resilience. Interventions to improve sleep quality in adolescents by targeting family function may be more effective when incorporating resilience.

Age and sex differences in the effects of peer victimization on depressive symptoms: Exploring sleep problems as a mediator.

BACKGROUND: Peer victimization contributes to an elevated risk of adolescent depression. Although theoretical evidence has noted that peer victimization may disrupt sleep and subsequently increase levels of depressive symptoms, this pathway has never been tested. This study explores a novel mechanism leading from peer victimization to depressive symptoms through sleep problems and considers whether the direct and indirect pathways vary by age and sex of adolescents. METHODS: Data were from 4072 adolescents (2042 males, 2030 females; age range 14-19 years) residing in northern Taiwan. Mediation analyses were first conducted to understand the mediating role of sleep problems in the association between peer victimization and depressive symptoms for males and females, respectively. Moderated mediation analyses were then applied to test age differences in the direct and indirect pathways from peer victimization to depressive symptoms. RESULTS: Sleep problems mediated the association between peer victimization and depressive symptoms in adolescent females but not in males. Age further moderated the indirect pathway from peer victimization to depressive symptoms through sleep problems, such that the mediating effects of sleep problems increased with age and were only significant in older females. No age differences were observed for the direct effects of peer victimization on depressive symptoms in either males or females. LIMITATIONS: Study was not designed to infer causality and all variables were assessed by self-report measures. CONCLUSIONS: Our analyses revealed age and sex differences in the link from peer victimization to depressive symptoms through sleep problems. Efforts to reduce depressive symptoms in adolescent females who have experienced peer victimization may be made more effective by targeting sleep problems, especially in older female adolescents.

Sex differences in sleep patterns and changes in 7th to 12th graders: a longitudinal follow-up study in Taiwan.

Study Objectives: To assess the relationship between sex and the development of sleep patterns in adolescents from grade 7 to 12. Methods: We analyzed longitudinal data from annual school-based assessments of sleep habits among secondary school students in northern Taiwan. Measures of sleep patterns included sleep length on weekdays and weekends as well as weekend-weekday difference (WndD), defined as the discrepancy in the time in bed (TIB) between weekdays and weekends. Growth curve models were used to assess sex differences in sleep patterns. Associations between other covariates and sleep patterns were also explored. Results: We found shorter weekday TIB in girls compared with boys at all time points. In contrast, girls had longer weekend TIB than boys over time except in the 12th grade. WndD was also longer in girls than boys. All interaction terms between sex and time were insignificant, indicating that developmental change across time was not statistically different for boys and girls. Several other factors, namely, parental education, pubertal development, self-perceived health, weight status, depressive symptoms, academic stress, infrequent exercise, and substance use, were also found to be associated with sleep patterns. Conclusions: Our findings show a sex difference in TIB both on weekdays and weekends. No sex difference was found in the development of sleep patterns over time.

Dual Trajectories of Sleep Duration and Cigarette Smoking during Adolescence: Relation to Subsequent Internalizing Problems.

Decreasing sleep duration and increasing cigarette smoking of adolescents are major public health concerns. However, research examining connections between the developmental trajectories of the outcomes that are evolving contemporaneously and their relation to long-term outcomes is still lacking. This study examined distinct trajectories of sleep duration and cigarette smoking during adolescence, associations between these trajectories, and links with internalizing problems during young adulthood. Data were collected from 2510 adolescents who participated in a longitudinal study spanning from 2006 through 2014 in northern Taiwan. Group-based dual trajectory modeling was used to examine the dynamic relationships between sleep duration and cigarette smoking trajectories during adolescence. Multiple linear regression was used to understand the association between the distinct trajectories and subsequent internalizing problems. Three sleep duration trajectories (short decreasing, typical sleep, and long sleep) and three cigarette smoking trajectories (nonsmokers, late increasing, and escalating smokers) were identified. We found significant inter-relationships for sleep duration and cigarette smoking trajectories during adolescence; all atypical sleep duration trajectories conferred increased risks of increased cigarette smoking and vice versa. In addition, the effects of sleep duration and cigarette smoking on later internalizing problems were found to vary by sex and trajectory patterns. These results provide insight regarding the co-development of sleep duration and cigarette smoking trajectories during adolescence. We also highlight the different roles of sleep duration and cigarette smoking trajectories and their relation to internalizing problems of young adulthood.

Tubulozole-induced G2/M cell cycle arrest in human colon cancer cells through formation of microtubule polymerization mediated by ERK1/2 and Chk1 kinase activation.

Our studies demonstrated that human colon cancer cells (COLO 205), with higher expression level of check point kinase 1 (Chk1), were more sensitive to microtubule damage agent Tubulozole (TUBU) induced G2/M phase arrest than normal human colon epithelial (CRL) cells. TUBU (10 microM, for 3h) treatment resulted in rapid and sustained phosphorylation of Cdc25C (Ser-216) leading to increased 14-3-3beta binding. This resulted in increased nuclear translocation. In addition, TUBU induced phosphorylation of the Cdc25C (Ser-216) and Bad (Ser-155) proteins were blocked by Chk1 SiRNA-transfection. Surprisingly, cellular apotosis was observed in cells treated with TUBU after Chk1 SiRNA inhibition. We further demonstrated that extracellular signal-regulated kinase (ERK) activation by TUBU was needed for Chk1 kinase activation and microtubule formation as shown by the attenuation of these responses by the ERK1/2 specific inhibitor PD98059. However, TUBU induced ERK1/2 phosphorylation was not blocked in the Chk1 SiRNA-transfected COLO 205 cells. These results imply that ERK1/2 mediated Chk1 activation may be play an important role in determining TUBU induced G2/M arrest or apoptosis in COLO 205 cells.

The role of sleep problems in the relationship between peer victimization and antisocial behavior: A five-year longitudinal study.

RATIONALE: Peer victimization in children and adolescents is a serious public health concern. Growing evidence exists for negative consequences of peer victimization, but research has mostly been short term and little is known about the mechanisms that moderate and mediate the impacts of peer victimization on subsequent antisocial behavior. OBJECTIVE: The current study intended to examine the longitudinal relationship between peer victimization in adolescence and antisocial behavior in young adulthood and to determine whether sleep problems influence this relationship. METHODS: In total, 2006 adolescents participated in a prospective study from 2009 to 2013. The moderating role of sleep problems was examined by testing the significance of the interaction between peer victimization and sleep problems. The mediating role of sleep problems was tested by using bootstrapping mediational analyses. All analyses were conducted using SAS 9.3 software. RESULTS: We found that peer victimization during adolescence was positively and significantly associated with antisocial behavior in young adulthood (ß = 0.10, p < 0.0001). This association was mediated, but not moderated by sleep problems. Specifically, peer victimization first increased levels of sleep problems, which in turn elevated the risk of antisocial behavior (indirect effect: 0.01, 95% bootstrap confidence interval: 0.004, 0.021). CONCLUSION: These findings imply that sleep problems may operate as a potential mechanism through which peer victimization during adolescence leads to increases in antisocial behavior in young adulthood. Prevention and intervention programs that target sleep problems may yield benefits for decreasing antisocial behavior in adolescents who have been victimized by peers.

Disentangling the effects of depression on trajectories of sleep problems from adolescence through young adulthood.

BACKGROUND: Little is known about the differential influences of between- and within-person effects of depression as well as its long-term impacts on sleep problems in adolescents. This study aims to disentangle these differences by estimating three effects of depression (i.e., long-term, immediate, and fluctuating). METHODS: The sample included 1345 males and 1283 females in Taiwan. In multilevel models, the between- (i.e., long-term and immediate) and within-person (i.e., fluctuating) effects were estimated by using the average and time-varying scores of depression, respectively. The interactions between long-term and the other effects were also tested to determine the moderating effects of long-term influences. RESULTS: Significant immediate and long-term effects of depression were found for both sexes, indicating that adolescents with higher levels of depression were at increased risks for future sleep problems. For females only, the long-term effects further exacerbated the negative influences of immediate effects of depression on sleep problems. Moreover, the fluctuating effects were found to change over time in females and the influences were more pronounced in young adulthood. LIMITATIONS: The self-reported measures of both depression and sleep problems may produce common method variance and bias the results. Our measurements were adapted from various existing scales to increase their applicability; therefore, the internal consistency was not high. CONCLUSIONS: Our findings provide insight regarding who is at risk for sleep problems and when this risk would occur based on the effects of depression. They also highlight the importance of both immediate and long-term effects of depression on development of sleep problems.