Risk-taking and self-harm behaviors as markers of adolescent borderline personality disorder.

Adolescence is a critical period for early identification and intervention of borderline personality disorder (BPD). Risk-taking and self-harm behaviors (RSB) have been identified as promising early markers of BPD and correlates of depression in school-based samples. The present study aimed, first, to examine the association between RSB and BPD in a clinical sample of adolescents and, second, to examine whether RSB are also linked to depression. N = 405 participants (82.7% female) were recruited from an outpatient clinic for adolescents with RSB. RSB assessed included truancy, excessive media use, alcohol, tobacco, and illicit drug use, sexual risk-taking, and self-harm behavior. Regression analyses and generalized linear models were performed to examine the associations between individual RSB or patterns of RSB (identified using latent class analysis, LCA) and a diagnosis and severity of BPD or depression. All RSB (except excessive media use) were positively associated with BPD diagnosis and severity. In contrast, only non-suicidal self-injury (NSSI) and suicide attempts were positively associated with depression diagnosis and severity, while illicit drug use was negatively associated with depression severity. The LCA yielded two classes differing in the occurrence of RSB. The high RSB class was more likely to have a BPD diagnosis and greater BPD severity than the low RSB class. Classes did not differ regarding depression diagnosis or severity. As NSSI and suicide attempts were associated with both BPD and depression, the presence of additional RSB, besides self-harm behavior, may represent a specific risk marker for BPD in adolescents.

Associations of psychoactive substances and steroid hormones in hair: Findings relevant to stress research from a large cohort of young adults.

OBJECTIVE: Epidemiological studies increasingly use hair samples to assess people's cumulative exposure to steroid hormones, but how the use of different psychoactive substances may affect steroid hormone levels in hair is, so far, largely unknown. The current study addresses this gap by establishing the substance exposure correlates of cortisol, cortisone, and testosterone in hair, while also accounting for a number of relevant covariates. METHOD: Data came from a large urban community-sample of young adults with a high prevalence of substance use (N = 1002, mean age=20.6 years, 50.2% female), who provided 3 cm of hair samples. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) quantified cortisol, cortisone, and testosterone, as well as delta-9-tetrahydrocannabinol (THC), 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy"), cocaine, several opioids, and their respective metabolites. Multiple linear regression models with covariates were used to predict steroid hormone levels from substance exposure in a four-step approach: In the full sample, low and high substance hair concentrations (median split) were first tested against no use for each substance individually (step 1) and for all substances together (step 2). Then, within the participants with any substance in hair only, the continuous hair concentration of each substance in pg/mg (step 3) and finally of all substances together, were regressed (step 4). RESULTS: Low, high, and continuous levels of THC in hair were robustly associated with higher levels of cortisol (sig. in step 1 low THC: ß = 0.29, p = .021; high THC: ß = 0.42, p = .001; step 2: low THC: ß = 0.27, p = 0.036, and high THC: ß = 0.40, p = .004, and step 4: ß = 0.12, p = .041). Participants with high MDMA levels had higher levels of cortisone without adjusting for other substances (step 1: ß = 0.34, p = .026), but this effect was not significant in the other models. While high THC levels were associated with lower levels of testosterone in step 2 (ß = -0.35, p = .018), MDMA concentration was positively related to testosterone concentration with and without adjusting for other substances (step 3: ß = 0.24, p = .041; step 4: ß = 0.17, 95%, p = .015) in male participants. CONCLUSION: The use of psychoactive substances, especially of cannabis and ecstasy, should be considered in studies investigating steroid hormones in hair.

An integrative approach for the analysis of risk and health across the life course: challenges, innovations, and opportunities for life course research.

Life course epidemiology seeks to understand the intricate relationships between risk factors and health outcomes across different stages of life to inform prevention and intervention strategies to optimize health throughout the lifespan. However, extant evidence has predominantly been based on separate analyses of data from individual birth cohorts or panel studies, which may not be sufficient to unravel the complex interplay of risk and health across different contexts. We highlight the importance of a multi-study perspective that enables researchers to: (a) Compare and contrast findings from different contexts and populations, which can help identify generalizable patterns and context-specific factors; (b) Examine the robustness of associations and the potential for effect modification by factors such as age, sex, and socioeconomic status; and (c) Improve statistical power and precision by pooling data from multiple studies, thereby allowing for the investigation of rare exposures and outcomes. This integrative framework combines the advantages of multi-study data with a life course perspective to guide research in understanding life course risk and resilience on adult health outcomes by: (a) Encouraging the use of harmonized measures across studies to facilitate comparisons and synthesis of findings; (b) Promoting the adoption of advanced analytical techniques that can accommodate the complexities of multi-study, longitudinal data; and (c) Fostering collaboration between researchers, data repositories, and funding agencies to support the integration of longitudinal data from diverse sources. An integrative approach can help inform the development of individualized risk scores and personalized interventions to promote health and well-being at various life stages.

The worst and the best: new insights into risk and resilience in young adults from the COVID-19 pandemic.

Historic declines in young people's mental health began to emerge before the COVID-19 pandemic. In the face of this youth mental health crisis, the pandemic constituted a naturalistic stressor paradigm that came with the potential to uncover new knowledge for the science of risk and resilience. Surprisingly, approximately 19-35% of people reported better well-being in the first few months of the COVID-19 pandemic than before. Therefore, in May and September 2020, we asked N=517 young adults from a cohort study to describe the best and the worst aspects of their pandemic lives (N=1,462 descriptions). Inductive thematic analysis revealed that the best aspects included the deceleration of life and a greater abundance of free time, which was used for hobbies, healthy activities, strengthening relationships, and for personal growth and building resilience skills. Positive aspects also included a reduction in educational pressures and work load and temporary relief from climate change concerns. The worst aspects included disruptions and changes to daily life; social distancing and restrictions of freedoms; negative emotions that arose in the pandemic situation, including uncertainty about the future; and the growing polarization of society. Science that aims to reverse the youth mental health crisis must pay increased attention to sources of young people's distress that are not commonly measured (e.g., their educational, work, and time pressures; their fears and uncertainties about their personal, society's, and the global future), and also to previously untapped sources of well-being - including those that young people identified for themselves while facing the COVID-19 pandemic. Supplementary Information: The online version contains supplementary material available at 10.1007/s42844-023-00096-y.

When Substance Use Is Underreported: Comparing Self-Reports and Hair Toxicology in an Urban Cohort of Young Adults.

OBJECTIVE: Large-scale epidemiological research often uses self-reports to determine the prevalence of illicit substance use. Self-reports may suffer from inaccurate reporting but can be verified with objective measures. This study examined the following: the prevalence of illicit and non-medical substance use with self-reports and hair toxicology, the convergence of self-reported and objectively quantified substance use, and the correlates of under- and overreporting. METHOD: The data came from a large urban cohort study of young adults (n = 1,002, mean age = 20.6 years, 50% female). The participants provided 3 cm of hair (covering the previous 3 months) and reported their illicit and non-medical substance use and their sociodemographic, psychological, and behavioral characteristics. Hair toxicology analyses targeted cannabinoids, ketamine, opiates/opioids, stimulants including 3,4-methylenedioxymethamphetamine, and relevant metabolites. RESULTS: Self-reports underestimated the prevalence of most substances by 30% to 60% compared to hair tests. The average detection ratio (hair test/self-report) was 1.50. Hair tests were typically more sensitive than self-reports. Underreporting was associated with a low level of that substance in hair. Self-reported delinquency and psychopathology were correlated with an increased likelihood of concordant positive self-reports and hair tests compared to underreporting. Overreporting was associated with infrequent self-reported use. CONCLUSION: Our study suggests that self-reports underestimate young adults' exposure to illicit substances and non-medical use of prescription drugs. Consequently, estimates of associations between substance use and risk factors or outcomes are likely biased. Combining self-reports with hair tests may be most beneficial in study samples with occasional substance use. Researchers can use specific factors (eg, detection ratios) to adjust prevalence estimates and correlations based on self-reports.

Self-, other-, and dual-harm during adolescence: a prospective-longitudinal study of childhood risk factors and early adult correlates.

BACKGROUND: Little is known about the childhood antecedents and adult correlates of adolescent dual-harm (i.e. co-occurring self- and other-harm). We examine the longitudinal associations between (a) social and psychological risk factors in childhood and adolescent dual-harm and (b) adolescent dual-harm and social and mental health impairments in early adulthood. METHODS: Participants (N = 1482) are from a prospective longitudinal community-representative study. Dual-, self-, and other-harm were self-reported at ages 13, 15, and 17. Social and psychological risk factors in childhood were assessed between 7 and 11; early adult correlates at age 20. Groups with dual-harm, self-harm only, other-harm only, and no harm were compared. RESULTS: Between 13 and 17, 7.2% of adolescents reported dual-harm (self-harm only: 16.2%; other-harm only: 13.3%). Some childhood risk factors (e.g. sensation-seeking, parental divorce, victimization by peers) characterized all harm groups; others were common to the dual- and self-harm (anxiety/depressive symptoms, relational aggression) or dual- and other-harm groups only (low self-control, substance use, delinquency). Adolescents with dual-harm had reported more physical aggression and harsh parenting, and lower school bonding in childhood than any other group. In early adulthood, they reported more anxiety/depressive symptoms, psychopathy symptoms, homicidal ideations, delinquency, and victimization experiences than any other group. CONCLUSIONS: Adolescent dual-harm follows psychological problems and social disconnection in childhood and signals risk of psychopathology and isolation in early adulthood. To curb the burden from dual-harm, interventions must target adolescents, families, peer networks, and school environments. Differentiating youth with dual-harm from those with single-harm is important for developing personalized treatments.

Developmental Trajectories of Self-, Other-, and Dual-Harm across Adolescence: The Role of Relationships with Peers and Teachers.

INTRODUCTION: We investigated the longitudinal course of self-, other-, and dual-harm in adolescents, focusing on the infliction of physical injury on oneself, another person, or both parties, respectively. We examined the within-person transitions between these types of harm and whether relationships with peers and teachers predict individual harm trajectories. METHODS: We used community-representative longitudinal data (N = 1,482; 52% male; 50% both parents born abroad). The participants self-reported self- and other-harm at 13, 15, 17, and 20 years. We assigned them to groups with self-, other-, dual- or no harm at specific assessments. Bullying victimization and relationship quality with classmates and teachers were assessed at 13 and 17. We estimated transition probabilities between the harm groups using latent Markov chain models. RESULTS: At age 13, 3% of the sample engaged in dual-harm, 10% in self-harm only, and 7% in other-harm only. These percentages decreased in late adolescence. Initial dual-harm was often followed by sex-specific single-harm: most of the female participants transitioned to self-harm, and male participants to other-harm. Those in the initial dual-harm group were less likely to stop harming than those in the initial single-harm groups (p < 0.05). Adverse relationship experiences generally predicted harm. A positive teacher-student bond was associated with the cessation of single-harm. CONCLUSION: Single- and dual-harm in the form of physical injury typically emerge by mid-adolescence. After this point, adolescents commonly maintain harm, especially those who have presented with dual-harm. Helping adolescents cope with adverse relationship experiences and creating opportunities for positive relationship experiences could address these harmful behaviors.

Maternal Depressive Symptoms and Adolescents' Unhealthy Behavior: A 15-year Longitudinal Study.

OBJECTIVES: First, to leverage 15 years of longitudinal data, from child ages 2 to 17, to examine whether maternal depressive symptoms in early and middle childhood and in adolescence predict their child's unhealthy behaviors during adolescence. Second, to examine whether the timing of maternal depressive symptoms or specific unhealthy behaviors matter and whether child depressive symptoms and body mass index explain these associations. METHODS: Data came from a prospective-longitudinal community sample with multi-informant data (N = 213) from child ages 2 to17. A cumulative adolescent unhealthy behavior index was calculated, summing the presence of poor sleep, poor diet, physical inactivity, sedentary behavior, and smoking. Regression analyses examined associations of maternal depressive symptoms in early childhood (ages 2 to 5), middle childhood (ages 7 to 10), and adolescence (age 15) with adolescents' unhealthy behaviors (ages 16 to17). Indirect effects of child depressive symptoms and body mass index were tested using a path model. RESULTS: Adolescents' unhealthy behaviors were common (eg, 2 out of 3 engaged in at least 1 unhealthy behavior). Higher levels of maternal depressive symptoms in middle childhood and adolescence were associated with adolescent engagement in more unhealthy behaviors at ages 16 to 17. Maternal depressive symptoms in early childhood were associated with adolescent unhealthy behaviors through indirect effects involving children's depressive symptoms and continuity of maternal depressive symptoms. CONCLUSIONS: Maternal depressive symptoms are associated with the number of adolescent unhealthy behaviors, both directly and indirectly. Promoting mothers' mental health can be crucial for promoting children's health behaviors and health.

Suicidal ideation and self-injury in LGB youth: a longitudinal study from urban Switzerland.

BACKGROUND: Adolescent suicidality, suicidal ideation (SUI) and self-harming behaviour (SI) are major public health issues. One group of adolescents known to be particularly prone to suicidality and mental health problems is lesbian, gay and bisexual (LGB) youth. Although the social acceptance of the LGB community has increased in recent years, LGB individuals are still at risk of mental health issues and suicidal behaviour. More longitudinal research looking into the associations between sexual orientation (SO) and facets of mental health across adolescence is warranted. METHODS: This research examined associations between sexual orientation, suicidal ideation and self-injury at 15, 17 and 20 years of age in a community-based sample of 1108 Swiss adolescents (51.1% females/48.9% males). At the age of 15 years, participants provided information regarding their SUI and SI. At 17 and 20 years of age, participants also reported their SO. RESULTS: Twelve percent of the female participants and 4.4% of the male participants reported identifying as LGB at 17 and 20 years of age. Self-reports of bi- or same-sex attraction increased over time in both genders, with the increase being more pronounced in females. LGB adolescents of both genders showed significantly higher percentages of SUI and SI at the ages of 17 and 20 years than their heterosexual peers. CONCLUSIONS: The findings confirm a higher risk of SUI and SI in adolescents who identify as LGB. Future studies should develop interventions targeting mental health from early adolescence with the aim of reducing disparities related to SO.

Emotional distress in young adults during the COVID-19 pandemic: evidence of risk and resilience from a longitudinal cohort study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic and associated lockdown could be considered a 'perfect storm' for increases in emotional distress. Such increases can only be identified by studies that use data collected before and during the pandemic. Longitudinal data are also needed to examine (1) the roles of previous distress and stressors in emotional distress during the pandemic and (2) how COVID-19-related stressors and coping strategies are associated with emotional distress when pre-pandemic distress is accounted for. METHODS: Data came from a cohort study (N = 768). Emotional distress (perceived stress, internalizing symptoms, and anger), COVID-19-related stressors, and coping strategies were measured during the pandemic/lockdown when participants were aged 22. Previous distress and stressors were measured before COVID-19 (at age 20). RESULTS: On average, participants showed increased levels of perceived stress and anger (but not internalizing symptoms) during the pandemic compared to before. Pre-COVID-19 emotional distress was the strongest predictor of during-pandemic emotional distress, followed by during-pandemic economic and psychosocial stressors (e.g. lifestyle and economic disruptions) and hopelessness, and pre-pandemic social stressors (e.g. bullying victimization and stressful life events). Most health risks to self or loved ones due to COVID-19 were not uniquely associated with emotional distress in final models. Coping strategies associated with reduced distress included keeping a daily routine, physical activity, and positive reappraisal/reframing. CONCLUSIONS: In our community sample, pre-pandemic distress, secondary consequences of the pandemic (e.g. lifestyle and economic disruptions), and pre-pandemic social stressors were more consistently associated with young adults' emotional distress than COVID-19-related health risk exposures.

Pathways from maternal depressive symptoms to children's academic performance in adolescence: A 13-year prospective-longitudinal study.

The pathways through which exposure to maternal depressive symptoms in early childhood are linked to academic performance during adolescence are poorly understood. This study tested pathways from maternal depressive symptoms (age 2-5) to adolescent academic performance (age 15) through cumulative parenting risk (age 7) and subsequent child functioning (age 10), using multi-informant data from a prospective longitudinal community study spanning 13 years (N = 389, 47% male, 68% White). Structural equation models testing indirect effects revealed small associations between maternal depressive symptoms and increased cumulative parenting risk and poorer child functioning, and, via these pathways, with poorer academic performance. Thus, childhood exposure to maternal depressive symptoms may be associated with pathways of risk that could limit children's educational opportunities.

High Prevalence and Early Onsets: Legal and Illegal Substance Use in an Urban Cohort of Young Adults in Switzerland.

INTRODUCTION: Debates about the legalization of illegal substances (e.g., cannabis) continue around the globe. A key consideration in these debates is the adequate protection of young people, which could be informed by current prevalence and age-of-onset patterns. For Switzerland, such information is limited, which is particularly true for women, despite advanced political efforts to legalize cannabis. The objective of the current study was to investigate substance use prevalence rates and ages of onset in a community-representative sample of female and male young adults in Switzerland. METHODS: Data came from the Zurich Project on the Social Development from Childhood to Adulthood (z-proso). In 2018, participants (N = 1,180, 50.8% females) were ∼20 years old. Lifetime and past-year use of alcohol, tobacco, cannabinoids, stimulants, hallucinogens, opioids, and benzodiazepines were assessed with an extensive substance use questionnaire. Additionally, ages of onsets of the respective substances were estimated by averaging participants' self-reported ages of onsets from ages 13 to 20 (max. 4 assessments). RESULTS: 57% of 20-year-olds had used cannabinoids, 16% stimulants, 15% opioids (mostly codeine), and 8% hallucinogens in the past year. Males had higher prevalence than females for most drugs; nevertheless, females' prevalence rates were notably high. Legal substance use was typically initiated 1.3-2.7 years before legal selling age. Thus, almost half of the sample had consumed alcohol and tobacco by age 14. More than 40% of the total sample had smoked cannabis by age 16. Males initiated use of legal substances and cannabis earlier than females. DISCUSSION: Our recent community-representative data suggested unexpectedly high levels and early onsets of substance use compared to a previous Swiss surveys and also the European average. Drug policy debates should consider urban substance use patterns when considering legalization efforts.

Attitudes Toward COVID-19 Vaccination Among Young Adults in Zurich, Switzerland, September 2020.

Objectives: Young adults are essential to the effective mitigation of the novel coronavirus (SARS-CoV-2/COVID-19) given their tendency toward greater frequency of social interactions. Little is known about vaccine willingness during pandemics in European populations. This study examined young people's attitudes toward COVID-19 vaccines in Fall 2020. Methods: Data came from an ongoing longitudinal study's online COVID-19-focused supplement among young adults aged 22 in Zurich, Switzerland (N = 499) in September 2020. Logistic regressions examined young adults' likelihood of participating in COVID-19 immunization programs. Results: Approximately half of respondents reported being unlikely to get vaccinated against COVID-19. Compared to males, females were more likely to oppose COVID-19 vaccination (p < 0.05). In multivariate models, Sri Lankan maternal background and higher socioeconomic status were associated with a greater likelihood of getting vaccinated against COVID-19 (p < 0.05). Respondents were more likely to report a willingness to get vaccinated against COVID-19 when they perceived 1) an effective government response (p < 0.05) and 2) their information sources to be objective (p < 0.05). Conclusion: This study communicates aspects important to the development of targeted information campaigns to promote engagement in COVID-19 immunization efforts.

Frequent teenage cannabis use: Prevalence across adolescence and associations with young adult psychopathology and functional well-being in an urban cohort.

BACKGROUND: Amidst cannabis legalization efforts and laws, we do not fully understand how the youngest frequent cannabis users fare during young adulthood. This study aims to 1) examine the prevalence of cannabis use during adolescence, and 2) investigate links of frequent (i.e., weekly or daily) teenage cannabis use with psychopathology and functional well-being at age 20-compared to no or occasional use. METHODS: Data came from a prospective-longitudinal cohort study (assessments from 2004 to 2018, from ages 7-20) in an urban setting (N = 1482). Substance use was assessed with self-reports between ages 13 and 20. At age 20, participants reported on psychopathology (psychotic symptoms, problematic substance use, aggression, and internalizing symptoms) and functional well-being (delinquency, financial difficulties, social exclusion, general well-being, and not being in education, employment, or training). Covariates were based on self-, parent-, teacher-, and behavioral measures. FINDINGS: Almost one in five adolescents had used cannabis frequently between ages 13 and 17 (26.6% of males, 9.8% of females). Adjusting nearly 20 potential confounders, frequent teenage cannabis use was associated with age 20 problematic substance use and poorer functional well-being compared to the no cannabis use and the occasional use groups. Frequent teenage cannabis use was more consistently associated with age 20 functional outcomes compared to frequent teenage nicotine or alcohol use. CONCLUSIONS: Frequent teenage cannabis use was common and associated with problematic substance use, more delinquency, and poorer functional well-being at age 20. Accordingly, frequent teenage cannabis users could experience increased difficulties in mastering the transitions of young adulthood.

Self-Injury and Domestic Violence in Young Adults During the COVID-19 Pandemic: Trajectories, Precursors, and Correlates.

We examined the longitudinal course of, and pre- and during-pandemic risk factors for, self-injury and domestic physical violence perpetration in young adults during the COVID-19 pandemic. Data came from a Swiss longitudinal study (N = 786, age ˜22 in 2020), with one prepandemic (2018) and four during-pandemic assessments (2020). The prevalence of self-injury did not change between April (during the first Swiss national lockdown) and September 2020 (postlockdown). Domestic violence perpetration increased temporarily in males. Prepandemic self-injury was a major risk factor for during-pandemic self-injury. Specific living arrangements, pandemic-related stressor accumulation, and a lack of adaptive coping strategies were associated with during-pandemic self-injury and domestic violence. Stressor accumulation had indirect effects on self-injury and domestic violence through negative emotions.

Developmental Associations Between Sympathy and Mutual Disclosure in Friendships From Mid-Adolescence to Early Adulthood.

Sympathy is regarded as an important precursor to the development of emotional intimacy, including mutual disclosure. In turn, emotional intimacy is assumed to foster the development of sympathy. Yet, research has not examined how sympathy and mutual disclosure in generic friendships are mutually related to one another during mid-adolescence to early adulthood. Data came from three waves of the Swiss Survey of Children and Youth (COCON; N = 1,258). Bidirectional links between sympathy and mutual disclosure were tested with autoregressive cross-lagged panel analyses. Sympathy at age 15 was associated with mutual disclosure in friendships at 18, which in turn was associated with sympathy at 21. Multi-group models suggested that our model better describes these processes in females than in males.

Prevalence and Childhood Precursors of Opioid Use in the Early Decades of Life.

Importance: Opioid use disorder and opioid deaths have increased dramatically in young adults in the US, but the age-related course or precursors to opioid use among young people are not fully understood. Objective: To document age-related changes in opioid use and study the childhood antecedents of opioid use by age 30 years in 6 domains of childhood risk: sociodemographic characteristics; school or peer problems; parental mental illness, drug problems, or legal involvement; substance use; psychiatric illness; and physical health. Design, Setting, and Participants: This community-representative prospective longitudinal cohort study assessed 1252 non-Hispanic White individuals and American Indian individuals in rural counties in the central Appalachia region of North Carolina from January 1993 to December 2015. Data were analyzed from January 2019 to January 2020. Exposures: Between ages 9 and 16 years, participants and their parents were interviewed up to 7 times using the Child and Adolescent Psychiatric Assessment and reported risk factors in 6 risk domains. Main Outcomes and Measures: Participants were assessed again at ages 19, 21, 25, and 30 years for nonheroin opioid use (any and weekly) and heroin use using the structured Young Adult Psychiatric Assessment. Results: Of 1252 participants, 342 (27%) were American Indian. By age 30 years, 322 participants had used a nonheroin opioid (24.2%; 95% CI, 21.8-26.5), 155 had used a nonheroin opioid weekly (8.8%; 95% CI, 7.2-10.3), and 95 had used heroin (6.6%; 95% CI, 5.2-7.9). Childhood risk markers for later opioid use included male sex, tobacco use, depression, conduct disorder, cannabis use, having peers exhibiting social deviance, parents with legal involvement, and elevated systemic inflammation. In final models, childhood tobacco use, depression, and cannabis use were most robustly associated with opioid use in young adulthood (ages 19 to 30 years). Chronic depression and dysthymia were strongly associated with any nonheroin opioid use (OR. 5.43; 95% CI, 2.35-12.55 and OR, 7.13; 95% CI, 1.99-25.60, respectively) and with weekly nonheroin opioid use (OR, 8.89; 95% CI, 3.61-21.93 and OR, 11.51; 95% CI, 3.05-42.72, respectively). Among young adults with opioid use, those with heroin use had the highest rates of childhood psychiatric disorders and comorbidities. Conclusions and Relevance: Childhood tobacco use and chronic depression may be associated with impaired reward system functioning, which may increase young adults' vulnerability to opioid-associated euphoria. Preventing and treating early substance use and childhood mental illness may help prevent later opioid use.

Polysubstance Use in Early Adulthood: Patterns and Developmental Precursors in an Urban Cohort.

Polysubstance use (i.e., simultaneous or sequential use of different psychoactive substances) is associated with increases in the risk of severe health problems and social impairments. The present study leverages community-representative, long-term longitudinal data from an urban cohort to assess: (a) the prevalence and continuation of polysubstance use between adolescence and early adulthood; (b) different patterns of polysubstance use (i.e., combinations of substances) in early adulthood; and (c) childhood risk factors for polysubstance use in early adulthood. At age 20 (n = 1,180), respondents provided comprehensive self-reported information on past-year substance use, including use of legal and illicit substances (e.g., cannabinoids, stimulants, and hallucinogens), and nonmedical use of prescription drugs (e.g., opioids, tranquilizers). In adolescence (ages 13-17), limited versions of this questionnaire were administered. In childhood (ages 7-11), potential risk factors, including individual-level factors (e.g., sensation-seeking, low self-control, aggression, and internalizing symptoms) and social-environmental factors (e.g., social stressors, exposure to others' substance use), were assessed. We fitted latent class models to identify classes of participants with different substance use profiles in early adulthood. The results show that polysubstance use increased between early adolescence and early adulthood. The continuation of polysubstance use was common (stability between all adjacent assessments: odds ratio >7). At age 20, more than one-third of participants reported polysubstance use (involving illicit substances, nonmedical use of prescription drugs, and cannabidiol). Four latent classes with polysubstance use were identified: (1) broad spectrum of substances; (2) cannabis and club drugs; (3) cannabis and the nonmedical use of prescription drugs; and (4) different cannabinoids. Risk factors for any polysubstance use included childhood sensation-seeking and exposure to others' substance use; some childhood risk factors were differentially associated with the four classes (e.g., low self-control in childhood was associated with an increased likelihood of being in the broad spectrum class). The classes also differed with regard to socio-demographic factors. This study revealed that polysubstance use is a widespread and multifaceted phenomenon that typically emerges during adolescence. To facilitate the design of tailored prevention mechanisms, the heterogeneity of polysubstance use and respective socio-demographic and developmental precursors need to be considered.

Non-compliance with COVID-19-related public health measures among young adults in Switzerland: Insights from a longitudinal cohort study.

RATIONALE: Adolescents and young adults were identified internationally as a group with potentially low compliance rates with public health measures aimed at curbing the spread of coronavirus disease 2019 (COVID-19). Although non-compliance research during pandemics has typically focused on concurrent correlates, less is known about how prior social and psychological risk factors are associated with non-compliance during pandemics. OBJECTIVE: This paper leverages a prospective-longitudinal cohort study with data before and during the pandemic to describe patterns of non-compliance with COVID- 19 related public health measures in young adults and to identify which characteristics increase the risk of non-compliance. METHODS: Data came from an ongoing cohort study in Zurich, Switzerland (n=737). Non-compliance with public health measures and concurrent correlates were measured at age 22. Antecedent sociodemographic, social, and psychological factors were measured at ages 15-20. Young adults generally complied with COVID-19 public health measures, although non-compliance with some measures (e.g., cleaning/disinfecting mobile phones, standing 1.5-2 meters apart) was relatively higher. RESULTS: Non-compliance, especially with hygiene-related measures, was more prevalent in males, and in individuals with higher education, higher SES, and a nonmigrant background. Non-compliance was higher in young adults who had previously scored high on indicators of "antisocial potential," including low acceptance of moral rules, pre-pandemic legal cynicism, low shame/guilt, low self-control, engagement in delinquent behaviors, and association with delinquent peers. Young adults with low trust, including in the government's measures for fighting the virus, also complied less. CONCLUSIONS: In order to increase voluntary compliance with COVID-19 measures, public health campaigns should implement strategies that foster moral obligation and trust in authorities, or leverage trustworthy individuals in the community to disseminate information. For young adults with low self-control, self-monitoring, environmental restructuring, or nudging may increase compliance. Long-term investments into integrating youth with antisocial potential into society may decrease rule-breaking behaviors, including during pandemics when compliance saves lives.

Self-injury from early adolescence to early adulthood: age-related course, recurrence, and services use in males and females from the community.

Adolescent self-injury is a widespread public health problem, but long-term longitudinal studies from European countries are rare. Self-injury in males and sex differences are poorly understood. This study describes the prevalence, frequency, age-related course, and recurrence of, and mental health services use related to adolescent self-injury. Data came from a Swiss prospective-longitudinal cohort study (N = 1482). Adolescents (52% male) reported frequency of self-injury and mental health services use (including reasons for and types of services use, hospitalizations) at ages 13, 15, 17, and 20. Between ages 13-20, 27% of adolescents reported self-injury at least once. In males, prevalence decreased from 12 to 5%; in females self-injury peaked at age 15 (16%) and then decreased (11% at age 20). In males, recurrence of self-injury increased after age 15 (from odds ratio [OR] < 3 to OR > 10); in females, recurrence was high from age 13 onwards (OR > 5). Predictors of recurrence included childhood/early adolescent internalizing symptoms and early self-injury onset. Typically, less than half of adolescents with self-injury used mental health services. Males with self-injury used services mainly for externalizing problems, learning difficulties, and attention/concentration problems; females for depression or self-injury, family problems, and victimization. Types of services used changed with age, and adolescents with self-injury had increased rates of hospitalization. There are notable sex differences in the longitudinal course of self-injury and reasons for related mental health services use. Treating early internalizing symptoms could be a promising target for preventing recurrent self-injury. Males are at particular risk of not receiving adequate treatment for self-injury.