Association of Problematic Internet Use With Psychotic Experiences and Depression in Adolescents: A Cohort Study.

BACKGROUND AND HYPOTHESIS: Problematic internet use (PIU) is prevalent among adolescents. Past research suggested cross-sectional associations between PIU and psychotic experiences, but little information is available on the longitudinal association. We hypothesized that PIU in adolescence may be longitudinally associated with psychotic experiences, adjusting for confounders. STUDY DESIGN: We analyzed a random sample of adolescents in the Tokyo Teen Cohort to examine how PIU at ages 10 (2012-2015), 12 (2014-2017), and 16 (2019-2021) was associated with mental health issues at age 16. PIU was evaluated by the modified Compulsive Internet Use Scale, psychotic experiences by the Adolescent Psychotic-like Symptom Screener, and depression by the Short Mood and Feelings Questionnaire. We also examined the mediating role of social withdrawal. STUDY RESULTS: We analyzed 3171 adolescents; 151 reported psychotic experiences and 327 reported depression at age 16. Compared with the lowest tertile PIU group, the highest tertile PIU group at age 12 showed an increased adjusted risk of psychotic experiences (RD 3.3%, 95% CI 2.9%-3.7%; RR 1.65, 95% CI 1.55-1.73) and depression (RD 5.9%, 95% CI 5.5%-6.3%; RR 1.61, 95% CI 1.55-1.68) at age 16. PIU at age 16 showed analogous results, while PIU at age 10 suggested a smaller impact. Social withdrawal mediated 9.4%-29.0% of the association between PIU and psychotic experiences. CONCLUSIONS: PIU is longitudinally associated with psychotic experiences and depression in adolescents. Further longitudinal and intervention studies are warranted to provide robust public health implications and foster a safer digital future.

Longitudinal trajectories of anterior cingulate glutamate and subclinical psychotic experiences in early adolescence: the impact of bullying victimization.

Previous studies reported decreased glutamate levels in the anterior cingulate cortex (ACC) in non-treatment-resistant schizophrenia and first-episode psychosis. However, ACC glutamatergic changes in subjects at high-risk for psychosis, and the effects of commonly experienced environmental emotional/social stressors on glutamatergic function in adolescents remain unclear. In this study, adolescents recruited from the general population underwent proton magnetic resonance spectroscopy (MRS) of the pregenual ACC using a 3-Tesla scanner. We explored longitudinal data on the association of combined glutamate-glutamine (Glx) levels, measured by MRS, with subclinical psychotic experiences. Moreover, we investigated associations of bullying victimization, a risk factor for subclinical psychotic experiences, and help-seeking intentions, a coping strategy against stressors including bullying victimization, with Glx levels. Finally, path analyses were conducted to explore multivariate associations. For a contrast analysis, gamma-aminobutyric acid plus macromolecule (GABA+) levels were also analyzed. Negative associations were found between Glx levels and subclinical psychotic experiences at both Times 1 (n = 219, mean age 11.5 y) and 2 (n = 211, mean age 13.6 y), as well as for over-time changes (n = 157, mean interval 2.0 y). Moreover, effects of bullying victimization and bullying victimization × help-seeking intention interaction effects on Glx levels were found (n = 156). Specifically, bullying victimization decreased Glx levels, whereas help-seeking intention increased Glx levels only in bullied adolescents. Finally, associations among bullying victimization, help-seeking intention, Glx levels, and subclinical psychotic experiences were revealed. GABA+ analysis revealed no significant results. This is the first adolescent study to reveal longitudinal trajectories of the association between glutamatergic function and subclinical psychotic experiences and to elucidate the effect of commonly experienced environmental emotional/social stressors on glutamatergic function. Our findings may deepen the understanding of how environmental emotional/social stressors induce impaired glutamatergic neurotransmission that could be the underpinning of liability for psychotic experiences in early adolescence.

The longitudinal relationship between dissociative symptoms and self-harm in adolescents: a population-based cohort study.

Previous studies have reported that dissociative symptoms (DIS) are associated with self-harm (SH) in adolescents. However, most of these studies were cross-sectional, which limits the understanding of their theoretical relationship. We aimed to investigate the longitudinal relationship between DIS and SH in the general adolescent population. We used data from the Tokyo Teen Cohort study (N = 3007). DIS and SH were assessed at times 1 and 2 (T1 and T2) (12 years of age and 14 years of age, respectively). DIS were assessed using the parent-report Child Behavior Checklist (CBCL), and severe dissociative symptoms (SDIS) were defined as a score above the top 10th percentile. The experience of SH within 1 year was assessed by a self-report questionnaire. The longitudinal relationship between DIS and SH was examined using regression analyses. Using logistic regression analyses, we further investigated the risk for SH at T2 due to persistent SDIS and vice versa. DIS at T1 tended to predict SH at T2 (odds ratio (OR) 1.11, 95% CI 0.99 to 1.25, p = 0.08), while SH at T1 did not predict DIS at T2 (B = - 0.03, 95% CI - 0.26 to 0.20, p = 0.81). Compared with adolescents without SDIS, those with persistent SDIS had an increased risk of SH at T2 (OR 2.61, 95% CI 1.28 to 5.33, p = 0.01). DIS tended to predict future SH, but SH did not predict future DIS. DIS may be a target to prevent SH in adolescents. Intensive attention should be given to adolescents with SDIS due to their increased risk of SH.

Uncovering associations between gender nonconformity, psychosocial factors, and mental health in adolescents: a birth cohort study.

BACKGROUND: Little information is available on the association between gender nonconformity during adolescence and subsequent mental health. While the distress related to gender nonconformity may be socially produced rather than attributed to individual-level factors, further research is needed to better understand the role of psychosocial factors in this context. METHOD: We analyzed data from the Tokyo Teen Cohort, obtained through random sampling of adolescents born between 2002 and 2004. We used inverse probability weighting to examine the association of gender nonconformity at ages 12 and 14 as a time-varying variable with subsequent mental health at age 16, while accounting for time-fixed and time-varying confounders. Furthermore, we used a weighting approach to investigate the mediating role of modifiable psychosocial factors in this association, addressing exposure-mediator and mediator-mediator interactions. RESULTS: A total of 3171 participants were analyzed. Persistent gender nonconforming behavior at ages 12 and 14 was associated with subsequent depression (ß = 2.02, 95% confidence interval [CI] 0.85 to 3.19) and psychotic experiences (ß = 0.33, 95% CI 0.14 to 0.52) at age 16. The results remained robust in sensitivity analyses. Approximately 30% of the association between gender nonconformity and depression was consistently mediated by a set of psychosocial factors, namely loneliness, bullying victimization, and relationships with mother, father, and friends. CONCLUSIONS: Persistent gender nonconformity during adolescence is associated with subsequent mental health. Psychosocial factors play a vital mediating role in this association, highlighting the essential need for social intervention and change to reduce stigmatization and ameliorate mental health challenges.

Adolescent psychotic experiences before and during the COVID-19 pandemic: a prospective cohort study.

BACKGROUND: Understanding the etiology of psychosis is essential to the development of preventive interventions. The COVID-19 pandemic provides a rare natural experiment that can expand our understanding of the role of social factors in the trajectories and etiology of psychosis across adolescence, particularly in Tokyo where the prevalence of actual COVID-19 infection remained low. We hypothesized that the likelihood of self-reporting psychotic experiences (PEs) would increase following the onset of the COVID-19 pandemic. METHODS: The Tokyo Teen Cohort (TTC) is a prospective cohort study of adolescents in the general population of the Tokyo metropolitan area, followed from age 10 to 16 years. We used multi-level linear regression models to test the associations between the phase of the COVID-19 pandemic and self-reported PEs. RESULTS: Among 1935 adolescents included in the analysis, a rapid increase in PEs occurred at the onset of the COVID-19 pandemic, following approximately 6 years of steady decline across prior waves. This association was more pronounced for boys compared to girls. This increase became more pronounced as the pandemic moved into later phases, defined based on contemporaneous sociopolitical changes in Tokyo (i.e. changes to school closure, social distancing guidelines, and the state of emergency status). CONCLUSIONS: The steady decline in PEs across adolescence was halted and reversed concurrent with the COVID-19 pandemic onset, despite very low rates of COVID-19 infection. This implicates COVID-19 related socioenvironmental factors as contributory etiological factors in the development of PEs in this adolescent cohort.

Sex Differences in Adolescent Depression Trajectory Before and Into the Second Year of COVID-19 Pandemic.

OBJECTIVE: Evidence on the impact of the COVID-19 pandemic on adolescent mental health is mixed and does not disentangle natural age-related changes. We compared depressive symptoms among 16-year-olds surveyed, at a fourth wave, before or during the pandemic, while accounting for expected trajectories of within-person change based on 3 prior waves. METHOD: In this longitudinal cohort of 3,171 adolescents in Tokyo, Japan, adolescents were grouped based on their age 16 survey timing: pre-pandemic (February 2019 to February 2020) and during-pandemic (March 2020 to September 2021). Depressive symptoms were self-reported using the Short Mood and Feelings Questionnaire. Mixed-effect models were fitted to assess group differences while controlling for previous trends. Variations by sex, household income, and pandemic phase (early, late first-year, and second-year) were examined. RESULTS: Of 2,034 eligible adolescents, 960 (455 girls) were assessed before and 1,074 (515 girls) during the pandemic. Overall, depressive symptoms increased by 0.80 points (95% CI 0.28-1.31, 0.15 SD of the population average). This increase varied by sex and pandemic phase. For boys the increase emerged in the late first-year phase and enlarged in the second-year phase (mean difference from pre-pandemic: 1.69, 0.14-3.24), whereas for girls it decreased in the early school-closure phase (mean difference: -1.98, -3.54 to -0.41) and returned to the pre-pandemic level thereafter, with no additional increases during the pandemic. CONCLUSION: Into the second year of the COVID-19 pandemic, depressive symptoms of 16-year-olds worsened above the expected age-related change only in boys. Continuous monitoring and preventive approaches for adolescents at the population level are warranted. DIVERSITY & INCLUSION STATEMENT: We worked to ensure that the study questionnaires were prepared in an inclusive way. We worked to ensure sex and gender balance in the recruitment of human participants. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.

Longitudinal Relationships Between Help-Seeking Intentions and Depressive Symptoms in Adolescents.

PURPOSE: Cross-sectional studies have shown an association between lower help-seeking intentions and greater depressive symptoms among adolescents. However, no longitudinal study has examined the direction of this association. The current study investigated whether help-seeking intentions and depressive symptoms are reciprocally associated at the within-person (individual) level during early to mid-adolescence. METHODS: Longitudinal data on help-seeking intentions and depressive symptoms in adolescents were obtained from a population-based birth cohort study (Tokyo Teen Cohort; N = 3,171) at four time points (10y, 12y, 14y, and 16y). A random intercept cross-lagged panel model was used to evaluate the within-person prospective associations between help-seeking intentions and depressive symptoms. RESULTS: At the within-person level, significant associations were consistently observed between antecedent greater depressive symptoms and subsequent lower help-seeking intentions across all time points (10y-12y: standardized regression coefficient (ß) = -0.12, p < .001; 12y-14y: ß = -0.07, p < .05; and 14y-16y: ß = -0.09, p < .01). Meanwhile, significant within-person associations were partly observed between antecedent lower help-seeking intentions and subsequent greater depressive symptoms from 10y to 12y (ß = -0.07, p < .05) and from 14y to 16y (ß = -0.12, p < .001). These prospective associations were almost the same when adjusted for the number of potential confidants as a time-varying confounder. DISCUSSION: Adolescents with worsening depressive symptoms may become increasingly reluctant to seek help over time. Proactive early recognition and intervention with support from parents, teachers, and other individuals may facilitate the management of depression in adolescents.

Association between menopause and suicidal ideation in mothers of adolescents: A longitudinal study using data from a population-based cohort.

BACKGROUND: Midlife suicide among women has attracted increasing research attention. This study aimed to investigate the longitudinal association between menopause and suicidal ideation among middle-aged women. METHODS: Our data were derived from the Tokyo Teen Cohort, a population-based survey of early adolescents (N = 3171) and their primary caregivers (typically, mothers) in Japan. A total of 2944 mothers (baseline mean age = 44.0 years) were included in the analysis. The baseline assessment in this study was performed at second-wave survey from July 2014 to January 2017. A follow-up assessment was conducted at fourth-wave survey from February 2019 to September 2021. Suicidal ideation at baseline and follow-up was assessed using the Suicidal Ideation subscale of the 28-item General Health Questionnaire. Menopausal stage was classified based on self-report at fourth-wave survey. RESULTS: Participants who started the perimenopausal stage after baseline were significantly more likely to have suicidal ideation at follow-up than those who did not have experienced menopausal transition yet. Participants with greater social support were less likely to report suicidal ideation at follow-up, even after adjusting for baseline suicidal ideation. LIMITATIONS: This study was based on self-report regarding menopausal stage and only included mothers of adolescents from Japan. An exact length of time from the onset to the presence of suicidal ideation was unavailable. CONCLUSIONS: Women who have experienced the onset of menopausal transition presented an increased risk of suicidal ideation. Psychosocial interventions to increase social support may be beneficial in preventing mental health inequalities during menopausal transitions.

Informal Caregiving in Adolescents from 10 to 16 Years Old: A Longitudinal Study Using Data from the Tokyo Teen Cohort.

There is growing evidence of the impact of informal caregiving on adolescent mental health, and its role is often hidden unintentionally or intentionally, which may hamper early identification and support for young informal caregivers. However, the quantitative evidence regarding household factors relating to informal caregiving has mostly been based on cross-sectional findings. This study examines the longitudinal associations between household characteristics and the duration of informal caregiving in adolescents from 10 to 16 years of age. Child-household respondent pairs (n = 2331) from the Tokyo Teen Cohort in Japan were followed every 2 years from 10 to 16 years of age. Informal caregiving was assessed repeatedly based on the household respondent's survey responses. Persistent caregiving was defined as daily caregiving at two or more waves. There were 2.2% of children who gave daily care at two or more waves. Cross-sectional associations with daily informal caregiving at each wave were found with girls, low household income, and cohabiting with grandparents. A significant association with persistent caregiving was found only in cohabiting with grandparents at 10 years of age after adjusting for sex, number of siblings, single parent, and household income. Our longitudinal examination highlighted cohabiting with grandparents as a preceding factor for persistent caregiving. Identification and support for young informal caregivers should be integrated into social care service systems for older adults. The mechanism of persistent caregiving requires clarification.

Corrigendum: Being praised for prosocial behaviors longitudinally reduces depressive symptoms in early adolescents: a population-based cohort study.

[This corrects the article DOI: 10.3389/fpsyt.2022.865907.].

Urinary exosomal microRNAs as predictive biomarkers for persistent psychotic-like experiences.

Psychotic-like experiences (PLEs) occur occasionally in adolescence and mostly disappear with increasing age. Their presence, if persistent, is considered a robust risk factor for subsequent psychiatric disorders. To date, only a few biological markers have been investigated for persistent PLE prediction. This study identified urinary exosomal microRNAs that can serve as predictive biomarkers for persistent PLEs. This study was part of a population-based biomarker subsample study of the Tokyo Teen Cohort Study. A total of 345 participants aged 13 (baseline) and 14 (follow-up) years underwent PLE assessments by experienced psychiatrists using semi-structured interviews. We defined remitted and persistent PLEs based on longitudinal profiles. We obtained urine at baseline and the expression levels of urinary exosomal miRNAs were compared between 15 individuals with persistent PLEs and 15 age- and sex-matched individuals with remitted PLEs. We constructed a logistic regression model to examine whether miRNA expression levels could predict persistent PLEs. We identified six significant differentially expressed microRNAs, namely hsa-miR-486-5p, hsa-miR-199a-3p, hsa-miR-144-5p, hsa-miR-451a, hsa-miR-143-3p, and hsa-miR-142-3p. The predictive model showed an area under the curve of 0.860 (95% confidence interval: 0.713-0.993) for five-fold cross-validation. We found a subset of urinary exosomal microRNAs that were differentially expressed in persistent PLEs and presented the likelihood that a microRNA-based statistical model could predict them with high accuracy. Therefore, urine exosomal miRNAs may serve as novel biomarkers for the risk of psychiatric disorders.

Lower help-seeking intentions mediate subsequent depressive symptoms among adolescents with high autistic traits: a population-based cohort study.

Adolescents with high autistic traits are at increased risk of depression. Despite the importance of seeking help for early intervention, evidence on help-seeking intentions amongst this population is scarce. Using a population-based cohort in Japan, we examined adolescents' help-seeking intentions and preferences by the level of autistic traits and tested its mediating role on the association between high autistic traits and depressive symptoms. At age 12, we measured parent-rated autistic traits using the short version of the Autism Spectrum Quotient and classified the adolescents into two groups (≥ 6 as AQhigh, < 6 as AQlow); help-seeking intentions and preferences were assessed through a depression vignette. At age 14, depressive symptoms were self-rated using the Short Mood and Feelings Questionnaire. Hypothesised associations between autistic traits and help-seeking intentions or depressive symptoms were tested applying multivariable regression modelling, while mediation was tested with structural equation modelling. Of the 2505 adolescent participants, 200 (8%) were classified as AQhigh. In both groups, the main source of help-seeking was their family; however, 40% of the AQhigh group reported having no help-seeking intentions compared to 27% in the AQlow. The AQhigh group was at increased risk of not having help-seeking intentions (OR 1.84, 95% CI 1.35-2.50) and higher depressive symptoms (b coefficient 1.06, 0.33-1.79). Help-seeking intentions mediated 18% of the association mentioned above. Interventions to promote help-seeking intentions among adolescents with high autistic traits could reduce their subsequent depressive symptoms. Ideally, such interventions should be provided prior to adolescence and with the involvement of their parents.

Attributes of auditory hallucinations that are associated with self-harm: A prospective cohort study.

There is a well-documented epidemiological association between auditory hallucinations and self-harm in the general population. However, there has been limited research examining specific characteristics of auditory hallucinations (e.g., type, source, or context of voices) as correlates of self-harm. We used prospective data from the Tokyo Teen Cohort to explore whether characteristics of voices reported at age 14 were differentially associated with self-harm behaviors at ages 14 and 16. Among respondents with auditory hallucinations, respondents who experienced voices that "said something bad" about them or commented on their thoughts and actions were most likely to report concurrent self-harm, whereas positive or praising voices were protective. Negative voices continued to predict self-harm two years later, at age 16, even with adjustment for self-harm at age 14. The age of the voices, source of the voices, and context (e.g., falling asleep or while sick) was not associated with likelihood of reporting concurrent or subsequent self-harm behaviors. Assessing for negative voices in particular, rather than auditory hallucinations or psychotic experiences more broadly, may provide a more specific indicator of risk for self-harm among adolescents. The real-world utility of these epidemiological findings should be further examined in clinical settings.

Auditory Hallucinations and Self-Injurious Behavior in General Population Adolescents: Modeling Within-Person Effects in the Tokyo Teen Cohort.

BACKGROUND AND HYPOTHESES: A wealth of evidence suggests that adolescent psychotic experiences (PEs), and especially auditory hallucinations (AHs), are associated with an increased risk for self-injurious behavior (SIB). However, the directionality and specificity of this association are not well understood, and there are no published studies investigating within-person effects over time. The present study aimed to test whether AHs and SIB prospectively increase reciprocal risk at the individual level during early-to-middle adolescence. STUDY DESIGN: Three waves (12y, 14y, and 16y) of self-reported AHs and SIB data from a large Tokyo-based adolescent birth cohort (N = 2825) were used. Random Intercept Cross-Lagged Panel Model (RI-CLPM) analysis was conducted to test the within-person prospective associations between AHs and SIB. STUDY RESULTS: At the within-person level, AHs were associated with subsequent SIB over the observation period (12y-14y: ß = .118, P < .001; 14-16y: ß = .086, P = .012). The reverse SIB->AHs relationship was non-significant at 12-14y (ß = .047, P = .112) but emerged from 14y to 16y as the primary direction of influence (ß = .243, P < .001). Incorporating depression as a time-varying covariate did not meaningfully alter model estimates. CONCLUSIONS: A complex bi-directional pattern of relationships was observed between AHs and SIB over the measurement period, and these relationships were independent of depressive symptoms. Adolescent AHs may be both a predictor of later SIB and also a manifestation of SIB-induced psychological distress.

Displacement of submacular hemorrhage secondary to age-related macular degeneration with subretinal injection of air and tissue plasminogen activator.

Submacular hemorrhage (SMH) can lead to devastating visual loss in patients with age-related macular degeneration. We retrospectively evaluated the surgical outcomes of vitrectomy with subretinal injection of tissue plasminogen activator, bevacizumab, and air in 13 cases. Visual prognosis, anatomical results obtained with optical coherence tomography (OCT), and their correlations were investigated. We analyzed OCT parameters including SMH height, pigment epithelial detachment (PED) height and width, and status of ellipsoid zone (EZ) line. Complete displacement of SMH was achieved in 12 eyes. At 3 months post-surgery, best-corrected visual acuity (BCVA) and SMH height exhibited significant improvements (P < 0.01). In eyes with preoperative SMH height < 300 µm and a detectable EZ line, BCVA was significantly improved at as early as 1 month, whereas the remaining eyes exhibited visual improvements only at 3 months. Postoperative BCVA positively correlated with preoperative BCVA (r = 0.86, P < 0.005), and negatively correlated with SMH size (r = 0.69, P < 0.01) and PED height (r = 0.58, P < 0.05) and width (r = 0.67, P < 0.05). Multivariate analyses confirmed preoperative BCVA as the predominant factor associated with postoperative BCVA (ß = 1.093, P < 0.05). In conclusion, significant improvements in BCVA and anatomical findings can be achieved with our reported surgical technique. Preoperative OCT findings may influence the duration required for visual improvements.

Predictors of chronic loneliness during adolescence: a population-based cohort study.

BACKGROUND: Adolescent loneliness is a growing public health issue owing to its adverse health impact. Although adolescent loneliness is common, its trajectories can show distinct patterns over time. However, there is limited knowledge regarding their determinants, particularly for chronic loneliness. We aimed to determine the predictors of loneliness trajectories across early-to-mid adolescence and examine their association with later suicidality. METHODS: Data were collected from 3165 participants from the population-based Tokyo Teen Cohort. Participants reported their loneliness at 10, 12, 14, and 16 years. Loneliness trajectories were identified using latent class growth analysis. We examined the predictive role of bullying victimization and parental psychological distress at age 10 via a multinomial logistic regression. Sociodemographic and child-related factors (i.e., chronic health conditions and cognitive delay) were included as covariates. The association between the trajectories, self-harm, and suicidal ideation by age 16 was investigated using Poisson regression. RESULTS: Four trajectories were identified: "consistently low" (2448, 77.3%), "moderate-decreasing" (185, 5.8%), "moderate-increasing" (508, 16.1%), and "consistently high" (24, 0.8%). Taking "consistently low" as a reference, experiences of bullying victimization predicted all the remaining trajectories [adjusted relative risk ratio 1.64, 95% confidence interval (CI) 1.18-2.28 for "moderate-decreasing," 1.88, 1.52-2.33 for "moderate-increasing," and 4.57, 1.97-10.59 for "consistently high"]. Parental psychological distress predicted the "moderate-increasing" (1.84, 1.25-2.71) and "consistently high" (5.07, 1.78-14.42) trajectories. The "consistently high" trajectory showed the greatest risk for self-harm and suicidal ideation (adjusted relative risk ratio 6.01, 95% CI 4.40-8.22; 2.48, 1.82-3.37, respectively); however, the "moderate-increasing" and "moderate-decreasing" trajectories were also at increased risk (moderate-increasing: 2.71, 2.23-3.30 for self-harm, 1.93, 1.69-2.19 for suicidal ideation; moderate-decreasing: 2.49, 1.91-3.26 for self-harm, 1.59, 1.33-1.91 for suicidal ideation). CONCLUSIONS: Bullying victimization and parental psychological distress at age 10 were independent determinants of increased and chronic loneliness trajectories across early-to-mid adolescence. Compared with "consistently low," all other loneliness trajectories were associated with an increased risk of adolescent suicidality. Interventions targeting adolescent loneliness should include approaches to mitigate bullying and parental psychological distress. These strategies may help prevent adolescent suicidality.

Hair zinc levels and psychosis risk among adolescents.

Recent meta-analyses have shown lower zinc and higher copper levels in the serum of people with schizophrenia than in healthy controls. However, the relationship between trace elements (TEs) and the pathophysiology of psychosis, including schizophrenia, remains unclear due to the antipsychotic effects on mineral levels. In this study, we aimed to determine the relationship between zinc and copper levels in hair and psychosis risk among drug-naïve adolescents. This study was conducted as a part of a population-based biomarker subsample study of the Tokyo Teen Cohort Study, including 252 community-dwelling 14-year-old drug-naïve adolescents. Zinc and copper levels in hair were measured using inductively coupled plasma mass spectrometry. The thought problems (TP) scale from the Child Behavior Checklist was used to evaluate psychosis risk. Regression analysis showed that hair zinc levels were negatively correlated with the TP scale (T-score) (ß = -0.176, P = 0.005). This result remained significant after adjusting for age and sex (ß = -0.175, P = 0.005). In contrast, hair copper levels were not associated with the TP scale (T-score) (ß = 0.026, P = 0.687). These findings suggest that lower zinc levels could be involved in the pathophysiology of psychosis, independent of antipsychotics. Further longitudinal studies are required to investigate whether hair zinc level is a useful new biomarker for assessing psychosis risk.

Maternal parenting stress from birth to 36 months, maternal depressive symptoms, and physical punishment to 10-year-old children: a population-based birth cohort study.

PURPOSE: This study aimed to investigate the association between parenting stress, maternal depressive symptoms, and use of physical punishment when the child is 10 years old. METHODS: Data from the Tokyo Early Adolescence Survey on early adolescents and primary caregivers (N = 4478) were used. Frequency of using physical punishment, level of depressive symptoms (Kessler Psychological Distress Scale 6), and maternal parenting stress experienced at 1, 3, 9, 18, and 36 months after birth were evaluated. Multiple linear and multinomial logistic regression analyses were conducted. RESULTS: Mothers (1633) who provided information on parenting stress at all the five points were included for the analysis. After controlling for the child's age, sex, birth weight, maternal age, and annual household income, presence of maternal parenting stress at every time point, except at three months after birth, was significantly associated with an increased risk of using physical punishment with the 10-year-old. After adjusting for levels of depressive symptoms, significant associations were found between use of physical punishment and maternal parenting stress at 1 month (adjusted odds ratio [OR] 1.71, 95% confidence interval [Cl] 1.12-2.61) and 36 months (adjusted OR 1.70, 95% CI 1.10-2.61) after birth. CONCLUSION: Maternal parenting stress experienced at 1 and 36 months after birth predicted use of physical punishment, even after adjusting for maternal depressive symptoms. Maternal support should, therefore, be provided to mothers to cope with parenting stress even three years after birth to prevent the use of physical punishment in early adolescence.

Role of advanced glycation end products in the longitudinal association between muscular strength and psychotic symptoms among adolescents.

Muscular strength, assessed by handgrip, is a risk indicator for psychiatric disorders, including psychosis. However, the biological mechanisms underlying this association remain unclear. Since advanced glycation end products (AGEs) play a key role in skeletal muscle underdevelopment and psychosis, we examined the role of AGEs in the longitudinal association between muscular strength and psychotic symptoms among adolescents. We first evaluated the direction of the relationship between handgrip strength and urine levels of pentosidine, a representative AGEs in a population-based birth cohort of 1,542 adolescents at ages 12 and 14. Then, we examined the role of AGEs in the longitudinal association between handgrip strength and thought problems (TP), as a psychotic symptom indicator, in a subsample of 256 adolescents at ages 13 and 14. An autoregressive cross-lagged model revealed that handgrip strength at age 12 negatively predicted pentosidine levels at age 14 (ß = -0.20, p < 0.001), whereas pentosidine levels at age 12 did not predict handgrip strength at age 14 (ß = 0.04, p = 0.062). Moreover, pentosidine levels had a significant indirect effect on the relationship between handgrip strength and TP (standard indirect effect = -0.051, p = 0.012), which remained significant after adjusting for gender and preceded TP and pentosidine levels. Thus, adolescents with low muscular strength are at a high risk of developing psychotic symptoms, which could be mediated by AGEs. Future studies need to investigate whether interventions focused on muscular strength prevent the accumulation of AGEs and thereby prevent the development of psychosis.

Sex-based differences in the longitudinal association between autistic traits and positive psychotic experiences in adolescents: A population-based cohort study.

Previous reports have suggested a cross-sectional association between autistic traits and psychotic experiences (PEs) in adolescents. However, while both autistic traits and PEs show sex-related differences, no studies have directly assessed whether such differences exist in the longitudinal association between autistic traits and PEs. Using a population-based adolescent cohort sample (n = 3007), we tested whether the longitudinal association between autistic traits and positive PEs was affected by sex-based differences using regression analyses. Autistic traits were assessed at 12 years old (timepoint 1 [T1]), and PEs were assessed at 12 and 14 years old (T1 and T2). Subsequently, we tested whether subdomains of autistic traits (difficulties in social interaction, communication, imagination, attention to detail, and attention switching) were associated with subtypes of PEs (auditory hallucinations, visual hallucinations, and delusions) using structural equation modeling, after controlling for PEs at T1, socio-economic status, school performance and parents' psychiatric disorders. After controlling for PEs at T1, we did not find any associations between autistic traits at T1 and PEs at T2 in both sexes. There was no significant positive or negative association between all subdomains of autistic traits and subtypes of PEs in both sexes. Autistic traits do not seem to predict future PEs in general adolescents regardless of sex.