A Psychometric Evaluation of the Dutch Revised Mystical Experience Questionnaire.

In the Netherlands, scientific interest in psychedelics and their subjective effects has been increasing. The present study examined the reliability, construct and predictive validity of the Dutch 30-item Revised Mystical Experience Questionnaire (MEQ30), a self-report measure that has been used to assess subjective and mystical experiences occasioned by psychedelics. In an online survey, 322 Dutch-speaking adults retrospectively reported on profound experiences with psychedelics. Confirmatory factor analyses demonstrated that both a four-factor structure and the same model extended with the MEQ30-total score as a second-order latent variable fit the data. Factor scores showed good internal reliability (α = between .81 and .94) and were significantly higher in participants that beforehand endorsed having had a mystical experience compared to those that did not, providing evidence for the construct validity of the questionnaire as a measure for self-reported mystical experiences. Additionally, MEQ30 scores significantly predicted the meaningfulness and spiritual significance of the psychedelic experience, as well as self-reported positive changes in well-being, life satisfaction and behavior, providing preliminary evidence for the predictive validity of the Dutch MEQ30. Findings suggest the reliability and validity of the Dutch MEQ30 and support the use of the scale in future studies on the subjective effects of psychedelics.

Urbanicity, hypothalamic-pituitary-adrenal axis functioning, and behavioral and emotional problems in children: a path analysis.

BACKGROUND: Urbanization is steadily increasing worldwide. Previous research indicated a higher incidence of mental health problems in more urban areas, however, very little is known regarding potential mechanisms underlying this association. We examined whether urbanicity was associated with mental health problems in children directly, and indirectly via hypothalamic-pituitary-adrenal (HPA)-axis functioning. METHODS: Utilizing data from two independent samples of children we examined the effects of current urbanicity (n = 306, ages seven to 12 years) and early childhood urbanicity (n = 141, followed from birth through age 7 years). Children's mothers reported on their mental health problems and their family's socioeconomic status. Salivary cortisol samples were collected during a psychosocial stress procedure to assess HPA axis reactivity to stress, and at home to assess basal HPA axis functioning. Neighborhood-level urbanicity and socioeconomic conditions were extracted from Statistics Netherlands. Path models were estimated using a bootstrapping procedure to detect indirect effects. RESULTS: We found no evidence for a direct effect of urbanicity on mental health problems, nor were there indirect effects of urbanicity through HPA axis functioning. Furthermore, we did not find evidence for an effect of urbanicity on HPA axis functioning or effects of HPA axis functioning on mental health problems. CONCLUSIONS: Possibly, the effects of urbanicity on HPA axis functioning and mental health do not manifest until adolescence. An alternative explanation is a buffering effect of high family socioeconomic status as the majority of children were from families with an average or high socioeconomic status. Further studies remain necessary to conclude that urbanicity does not affect children's mental health via HPA axis functioning.

From prenatal anxiety to parenting stress: a longitudinal study.

The objective of this study was to explore how maternal mood during pregnancy, i.e., general anxiety, pregnancy-specific anxiety, and depression predicted parenting stress 3 months after giving birth, thereby shaping the child's early postnatal environmental circumstances. To this end, data were used from 1073 women participating in the Dutch longitudinal cohort Generations2, which studies first-time pregnant mothers during pregnancy and across the transition to parenthood. Women filled out the State Trait Anxiety Inventory (STAI), Pregnancy-Related Anxiety Questionnaire-revised (PRAQ-R), and Beck Depression Index (BDI) three times during pregnancy: at 12, 22, and 32 weeks gestational age. Three months postpartum, a parenting stress questionnaire was filled out yielding seven different parenting constructs. Latent scores were computed for each of the repeatedly measured maternal mood variables with Mplus and parenting stress constructs were simultaneously regressed on these latent scores. Results showed that trait anxiety and pregnancy-specific anxiety were uniquely related to almost all parenting stress constructs, taking depression into account. Early prevention and intervention to reduce maternal anxiety in pregnancy could hold the key for a more advantageous trajectory of early postnatal parenting.

Pregnancy-related anxiety and depressive symptoms are associated with visuospatial working memory errors during pregnancy.

BACKGROUND: Cognitive deficits, especially in memory and concentration, are often reported during pregnancy. Similar cognitive dysfunctions can also occur in depression and anxiety. To date, few studies have investigated the associations between cognitive deficits and psychiatric symptoms during pregnancy. This field is of interest because maternal cognitive functioning, and particularly its higher-order aspects are related to maternal well-being and caregiving behavior, as well as later child development. METHODS: Pregnant women (N =230), reporting low (n =87), moderate (n =97), or high (n =46) levels of depressive, general anxiety and/or pregnancy-related anxiety symptoms (assessed repeatedly with EPDS, SCL-90/anxiety subscale, PRAQ-R2, respectively) were tested in mid-pregnancy for their cognitive functions. A computerized neuropsychological test battery was used. RESULTS: Pregnant women with high or moderate level of psychiatric symptoms had significantly more errors in visuospatial working memory/executive functioning task than mothers with low symptom level. Depressive symptoms throughout pregnancy and concurrent pregnancy-related anxiety symptoms were significant predictors of the performance in the task. General anxiety symptoms were not related to visuospatial working memory. LIMITATIONS: Cognitive functions were evaluated only at one time-point during pregnancy precluding causal conclusions. CONCLUSIONS: Maternal depressive symptoms and pregnancy-related anxiety symptoms were both associated with decrements in visuospatial working memory/executive functioning. Depressive symptoms seem to present more stable relationship with cognitive deficits, while pregnancy-related anxiety was associated only concurrently. Future studies could investigate, how stable these cognitive differences are, and whether they affect maternal ability to deal with demands of pregnancy and later parenting.

Pregnancy related anxiety and general anxious or depressed mood and the choice for birth setting: a secondary data-analysis of the DELIVER study.

BACKGROUND: In several developed countries women with a low risk of complications during pregnancy and childbirth can make choices regarding place of birth. In the Netherlands, these women receive midwife-led care and can choose between a home or hospital birth. The declining rate of midwife-led home births alongside the recent debate on safety of home births in the Netherlands, however, suggest an association of choice of birth place with psychological factors related to safety and risk perception. In this study associations of pregnancy related anxiety and general anxious or depressed mood with (changes in) planned place of birth were explored in low risk women in midwife-led care until the start of labour. METHODS: Data (n = 2854 low risk women in midwife-led care at the onset of labour) were selected from the prospective multicenter DELIVER study. Women completed the Pregnancy Related Anxiety Questionnaire-Revised (PRAQ-R) to assess pregnancy related anxiety and the EuroQol-6D (EQ-6D) for an anxious and/or depressed mood. RESULTS: A high PRAQ-R score was associated with planned hospital birth in nulliparous (aOR 1.92; 95% CI 1.32-2.81) and parous women (aOR 2.08; 95% CI 1.55-2.80). An anxious or depressed mood was associated with planned hospital birth (aOR 1.58; 95% CI 1.20-2.08) and with being undecided (aOR 1.99; 95% CI 1.23-2.99) in parous women only. The majority of women did not change their planned place of birth. Changing from an initially planned home birth to a hospital birth later in pregnancy was, however, associated with becoming anxious or depressed after 35 weeks gestation in nulliparous women (aOR 4.17; 95% CI 1.35-12.89) and with pregnancy related anxiety at 20 weeks gestation in parous women (aOR 3.91; 95% CI 1.32-11.61). CONCLUSION: Low risk women who planned hospital birth (or who were undecided) more often reported pregnancy related anxiety or an anxious or depressed mood. Women who changed from home to hospital birth during pregnancy more often reported pregnancy related anxiety or an anxious or depressed mood in late pregnancy. Anxiety should be adequately addressed in the process of informed decision-making regarding planned place of birth in low risk women.

Genome-wide association study of lifetime cannabis use based on a large meta-analytic sample of 32 330 subjects from the International Cannabis Consortium.

Cannabis is the most widely produced and consumed illicit psychoactive substance worldwide. Occasional cannabis use can progress to frequent use, abuse and dependence with all known adverse physical, psychological and social consequences. Individual differences in cannabis initiation are heritable (40-48%). The International Cannabis Consortium was established with the aim to identify genetic risk variants of cannabis use. We conducted a meta-analysis of genome-wide association data of 13 cohorts (N=32 330) and four replication samples (N=5627). In addition, we performed a gene-based test of association, estimated single-nucleotide polymorphism (SNP)-based heritability and explored the genetic correlation between lifetime cannabis use and cigarette use using LD score regression. No individual SNPs reached genome-wide significance. Nonetheless, gene-based tests identified four genes significantly associated with lifetime cannabis use: NCAM1, CADM2, SCOC and KCNT2. Previous studies reported associations of NCAM1 with cigarette smoking and other substance use, and those of CADM2 with body mass index, processing speed and autism disorders, which are phenotypes previously reported to be associated with cannabis use. Furthermore, we showed that, combined across the genome, all common SNPs explained 13-20% (P<0.001) of the liability of lifetime cannabis use. Finally, there was a strong genetic correlation (rg=0.83; P=1.85 × 10(-8)) between lifetime cannabis use and lifetime cigarette smoking implying that the SNP effect sizes of the two traits are highly correlated. This is the largest meta-analysis of cannabis GWA studies to date, revealing important new insights into the genetic pathways of lifetime cannabis use. Future functional studies should explore the impact of the identified genes on the biological mechanisms of cannabis use.

Adaption of pregnancy anxiety questionnaire-revised for all pregnant women regardless of parity: PRAQ-R2.

The 10-item Pregnancy-Related Anxiety Questionnaire-Revised (PRAQ-R) is a widely used instrument to assess and identify pregnancy-specific anxiety in nulliparous women. It has good psychometric values and predictive validity for birth and childhood outcomes. Nonetheless, the PRAQ-R is not designed for use in parous women, as particularly one item of the questionnaire is not relevant for women who gave birth before. We tested the factorial and scalar invariance of a modified PRAQ-R2 across nulliparous and parous women with an adapted item to fit both groups of pregnant women. A longitudinal study among 1144 pregnant women (n = 608 nulliparous and n = 536 parous) with two repeated measures of the PRAQ-R2 was used to test for measurement invariance of the instrument. Results show metric and scalar invariance, indicating that the PRAQ-R2 measures similar constructs on the same scale for all pregnant women at two different times during pregnancy. We conclude that the PRAQ-R2 can be used, compared, or combined in a sample of nulliparous and parous women.

The relationship between cannabis involvement and suicidal thoughts and behaviors.

BACKGROUND: In the present study, we examined the relationship between cannabis involvement and suicidal ideation (SI), plan and attempt, differentiating the latter into planned and unplanned attempt, taking into account other substance involvement and psychopathology. METHODS: We used two community-based twin samples from the Australian Twin Registry, including 9583 individuals (58.5% female, aged between 27 and 40). The Semi-Structured Assessment of the Genetics of Alcoholism (SSAGA) was used to assess cannabis involvement which was categorized into: (0) no cannabis use (reference category); (1) cannabis use only; (2) 1-2 cannabis use disorder symptoms; (3) 3 or more symptoms. Separate multinomial logistic regression analyses were conducted for SI and suicide attempt with or without a plan. Twin analyses examined the genetic overlap between cannabis involvement and SI. RESULTS: All levels of cannabis involvement were related to SI, regardless of duration (odds ratios [ORs]=1.28-2.00, p<0.01). Cannabis use and endorsing ≥3 symptoms were associated with unplanned (SANP; ORs=1.95 and 2.51 respectively, p<0.05), but not planned suicide attempts (p>0.10). Associations persisted even after controlling for other psychiatric disorders and substance involvement. Overlapping genetic (rG=0.45) and environmental (rE=0.21) factors were responsible for the covariance between cannabis involvement and SI. CONCLUSIONS: Cannabis involvement is associated, albeit modestly, with SI and unplanned suicide attempts. Such attempts are difficult to prevent and their association with cannabis use and cannabis use disorder symptoms requires further study, including in different samples and with additional attention to confounders.

The interrelationship between pregnancy-specific anxiety and general anxiety across pregnancy: a longitudinal study.

BACKGROUND: High levels of prenatal maternal anxiety - either pregnancy-specific anxiety or general anxiety - may have detrimental effects on both the mother and her child. It is currently unknown how these two different expressions of anxiety influence each other over time during pregnancy. AIMS: This study aimed to describe the relationship between state, trait and pregnancy-specific anxiety levels across pregnancy. METHODS: Longitudinal data from three data-waves of a large-scaled sample of nulliparous normal risk pregnant women were used to display associations over time by means of autoregressive and cross-lagged panel models. RESULTS: Cross-lagged, cross-time pathways from pregnancy-specific anxiety to state as well as trait anxiety were positively significant, while vice versa the most consistent links were found from trait anxiety to pregnancy-specific anxiety. CONCLUSIONS: We conclude that pregnancy-specific anxiety and general anxiety appear to influence each other over time, resulting in heightened anxiety for some soon-to-be mothers.

Prenatal cannabis exposure and infant outcomes: overview of studies.

Accumulating evidence from both human and preclinical studies indicates maternal substance use during pregnancy can affect fetal development, birth weight and infant outcomes. Thus, the prenatal period can be regarded as an important and potentially sensitive period of development. In this manuscript, an updated overview of studies on prenatal cannabis exposure in humans is presented, including recent studies conducted within the Generation R study. Findings on fetal growth, birth outcomes, early neonatal behavior and infant behavior and cognitive development are discussed in detail. Preclinical evidence and potential mechanisms are described as well, and recommendations for future studies are provided. It is concluded that evidence seems to suggest that fetal development is affected by prenatal maternal cannabis use, while findings on effects on infant behavior or cognition are inconsistent. Beyond infancy, subtle differences may be found in specific cognitive or behavioral outcomes, although replication studies in which pregnant women and their fetuses are exposed to current and probably higher levels of Δ9-tetrahydrocannabinol and novel designs are needed to come to firm conclusions.

A genetic perspective on the proposed inclusion of cannabis withdrawal in DSM-5.

BACKGROUND: Various studies support the inclusion of cannabis withdrawal in the diagnosis of cannabis use disorder (CUD) in the upcoming DSM-5. The aims of the current study were to (1) estimate the prevalence of DSM-5 cannabis withdrawal (criterion B), (2) estimate the role of genetic and environmental influences on individual differences in cannabis withdrawal and (3) determine the extent to which genetic and environmental influences on cannabis withdrawal overlap with those on DSM-IV-defined abuse/dependence. METHOD: The sample included 2276 lifetime cannabis-using adult Australian twins. Cannabis withdrawal was defined in accordance with criterion B of the proposed DSM-5 revisions. Cannabis abuse/dependence was defined as endorsing one or more DSM-IV criteria of abuse or three or more dependence criteria. The classical twin model was used to estimate the genetic and environmental influences on variation in cannabis withdrawal, along with its covariation with abuse/dependence. RESULTS: Of all the cannabis users, 11.9% met criteria for cannabis withdrawal. Around 50% of between-individual variation in withdrawal could be attributed to additive genetic variation, and the rest of the variation was mostly due to non-shared environmental influences. Importantly, the genetic influences on cannabis withdrawal almost completely (99%) overlapped with those on abuse/dependence. CONCLUSIONS: We have shown that cannabis withdrawal symptoms exist among cannabis users, and that cannabis withdrawal is moderately heritable. Genetic influences on cannabis withdrawal are the same as those affecting abuse/dependence. These results add to the wealth of literature that recommends the addition of cannabis withdrawal to the diagnosis of DSM-5 CUD.

Risk indicators of anxiety throughout adolescence: the TRAILS study.

BACKGROUND: The aim was to identify risk indicators from preadolescence (age period 10-12) that significantly predict unfavorable deviations from normal anxiety development throughout adolescence (age period 10-17 years). METHODS: Anxiety symptoms were assessed in a community sample of 2,220 boys and girls at three time-points across a 5-year interval. Risk indicators were measured at baseline and include indicators from the child, family, and peer domain. Associations with anxiety were measured with multilevel growth curve analyses. RESULTS: A stable difference in anxiety over adolescence was found between high and low levels of a range of child factors (frustration, effortful control), family factors (emotional warmth received from parents, lifetime parental internalizing problems), and peer factor (victims of bullying) (P <.001). In contrast, the difference in anxiety between high and low levels of factors, such as self-competence, unfavorable parenting styles, and bully victims, decreased over adolescence (P <.001). For other family factors, associations were weaker (.05

Maternal smoking during pregnancy, fetal arterial resistance adaptations and cardiovascular function in childhood.

OBJECTIVE: To unravel the mechanisms underlying the previously demonstrated associations between low birthweight and cardiovascular disease in adulthood, we examined whether maternal smoking during pregnancy leads to fetal arterial resistance adaptations, and subsequently to fetal growth retardation and changes in postnatal blood pressure and cardiac development. DESIGN: Prospective cohort study from early fetal life onwards. SETTING: Academic hospital. POPULATION: Analyses were based on 1120 children aged 2 years. METHODS: Maternal smoking during pregnancy [non-smoking, first trimester smoking, continued smoking (< 5 and ≥ 5 cigarettes/day)] was assessed by questionnaire. MAIN OUTCOME MEASURES: Third trimester placental and fetal arterial resistance indices and fetal growth were assessed by ultrasound and Doppler measurements. Postnatal blood pressure and cardiac structures (aortic root diameter, left atrial diameter, left ventricular mass) were measured at 2 years of age. RESULTS: First trimester smoking was not associated with third trimester placental and fetal blood flow adaptations. Continued smoking of ≥ 5 cigarettes/day was associated with an increased resistance in uterine, umbilical and middle cerebral arteries, and with a decreased flow and diameter of the ascending aorta. Among mothers who continued to smoke, the third trimester estimated fetal weights and birthweights were most affected in children with the highest umbilical artery resistance. Fetal arterial resistance indices were also associated with aortic root diameter and left atrial diameter. CONCLUSIONS: Fetal arterial resistance adaptations may be involved in the pathways leading from maternal smoking during pregnancy to low birthweight and cardiovascular developmental changes in childhood in the offspring.

Agreement between maternal cannabis use during pregnancy according to self-report and urinalysis in a population-based cohort: the Generation R Study.

AIM: To verify self-reported information on prenatal drug use in urine because reporting in pregnancy is sensitive to stigma and might lead to misclassification. METHODS: Using semiquantitative immunochemical analysis, the presence of the urinary metabolite (11-nor-Δ9-tetrahydrocannabinol- 9-carboxylic acid) was compared to self-reported prenatal cannabis use. Sensitivity and specificity for self-report and urinalysis outcomes were calculated and Yule's Y was used as an agreement measure. RESULTS: Urine samples were available for 3,997 pregnant women. Of these women, 92 reported having used cannabis during pregnancy (2.3%) and 71 had positive urine screens (1.8%). In total 35% of the 92 women with self-reported cannabis use also had a positive urine screen. Positive urines were relatively frequent in women reporting cannabis use before pregnancy only (7.6%) and in women with missing information (2.6%). Sensitivity and specificity of urinalysis compared to self-report were 0.46 and 0.98. Sensitivity and specificity of self-report compared to urinalysis were 0.36 and 0.99. Yule's Y amounted to 0.77, indicating substantial agreement between the measures. CONCLUSIONS: Our findings illustrate the difficulties in obtaining valid information on prenatal cannabis use. To improve the quality of cannabis use data, we suggest a 2-step approach starting with self-report.

DRD2 and DRD4 in relation to regular alcohol and cannabis use among adolescents: does parenting modify the impact of genetic vulnerability? The TRAILS study.

AIMS: The aims of the present study were to determine the direct effect of DRD2 and DRD4, as well as their interaction with parenting (i.e. rejection, overprotection and emotional warmth), on the development of regular alcohol and cannabis use in 1192 Dutch adolescents from the general population. METHODS: Information was obtained by self-report questionnaires. Perceived rejection, overprotection and emotional warmth were assessed at age 10-12. Regular alcohol and cannabis use were determined at age 15-18 and defined as the consumption of alcohol on 10 or more occasions in the past four weeks, and the use of cannabis on 4 or more occasions in the past four weeks. Models were adjusted for age, sex, parental alcohol or cannabis use, and externalizing behavior. RESULTS: Carrying the A1 allele of the DRD2 TaqIA polymorphism, or the 7 repeat DRD4, was not directly related to regular alcohol or cannabis use. In addition, adolescent carriers of these genetic risk markers were not more susceptible to the influence of less optimal parenting. Main effects for parenting indicated that overprotection increased the risk of regular alcohol use, whereas the risk of cannabis use was enhanced by parental rejection and buffered by emotional warmth. CONCLUSIONS: Our findings do not support an association between DRD2/DRD4 and regular alcohol and cannabis use in adolescents. Given the substance-specific influences of rejection, overprotection and emotional warmth, these parenting factors might be promising candidates for prevention work.

A systematic review of prospective studies on attention problems and academic achievement.

OBJECTIVE: Our aim was to provide an overview of prospective studies that have addressed the association between attention problems (AP, i.e. symptoms of hyperactivity and inattentiveness) and academic achievement (AA). METHOD: We conducted a systematic search in the literature. Normal population studies and clinical studies were included. The methodological quality of each study was evaluated by objective criteria. A best evidence synthesis was used to determine the strengths of the association. RESULTS: Sixteen studies were included. We found convincing evidence for a negative association between AP and AA. After controlling for intelligence, comorbidity, and socioeconomic status (SES), the association between the hyperactive symptoms of AP and AA was non-significant in two studies. CONCLUSION: Children with AP are at risk for lower AA and subsequent adverse outcomes later in life. Interventions in affected children should focus on their behavioural and educational development.

No effect of classroom sharing on educational achievement in twins: a prospective, longitudinal cohort study.

BACKGROUND: A returning dilemma for families with multiple births is whether twins should share the same, or a parallel classroom, or in other words, whether they should be separated at school or not. This study investigated the effects of sharing a classroom during primary school on cognitive achievement in twins. METHOD: Subjects were 839 monozygotic and 1164 dizygotic twin pairs who were registered at birth at The Netherlands Twin Register. A prospective, longitudinal study design was used with educational achievement at age 12 years, measured with a standardised test (CITO test), as outcome measure. RESULTS: Most twin pairs (72%) shared a classroom during their schooling, 19% were in separate, but parallel, classes, and 9% "partly" shared a classroom. Twins who were in parallel classrooms had higher CITO scores (mean 539.51; SD 8.12), compared to twins who shared a classroom (537.99; SD 8.52). When controlling for socioeconomic status, and externalising problems before starting primary school (age 3), there was no significant difference in educational achievement between separated and non-separated twin pairs (p = 0.138). In addition, there was no interaction with sex or zygosity of the twins (p = 0.798). CONCLUSION: There is no difference in educational achievement between twins who share a classroom and twins who do not share a classroom during their primary school time. The choice of separation should be made by teachers, parents and their twin children, based on individual characteristics of a twin pair.

Baseline cortisol measures and developmental pathways of anxiety in early adolescence.

OBJECTIVE: This study investigated whether baseline cortisol measures predicted future anxiety, and compared cortisol values of groups with different developmental pathways of anxiety. METHOD: Cortisol levels were assessed in 1768 individuals (10-12 years). Anxiety levels were assessed at the same age and 2 years later. RESULTS: Cortisol measures did not predict future anxiety levels. Individuals with persistent anxiety problems did not show higher morning cortisol levels than those with persistently low, decreasing, or increasing anxiety levels. Instead, individuals with persistently high anxiety levels showed significantly lower evening cortisol levels than all other individuals. Further, participants with increasing anxiety levels showed higher morning cortisol levels (area under the curve; AUC) than individuals with persistently low anxiety levels. CONCLUSION: The extent to which the HPA-axis - by itself - plays a role in the aetiology of anxiety is questionable. Interactions of the HPA-axis with other biological or environmental factors may be more important.

[Stress reactivity as an underlying mechanism of anxiety? Findings from the TRAILS study]. / Stressgevoeligheid als onderliggend mechanisme voor angstproblemen? Bevindingen uit de TRAILS-studie.

This short report provides an overview of the results of a recent Dutch study on the relation between anxiety and the reactivity of two important stress response systems: the autonomic nervous system and the hypothalamic-pituitary-adrenal axis. Future research will have to investigate the reactivity of both stress response systems in combination with several other important biological, psychological and social factors. In this way it should be possible to obtain more insight into the complex and interacting systems that underlie anxiety.

The developmental course of anxiety symptoms during adolescence: the TRAILS study.

BACKGROUND: Little is known about the development of anxiety symptoms from late childhood to late adolescence. The present study determined developmental trajectories of symptoms of separation anxiety disorder (SAD), social phobia (SoPh), generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD) in a large prospective community cohort. METHODS: Anxiety symptoms were assessed in a community sample of 2220 boys and girls at three time-points across a 5-year interval. The Revised Child Anxiety and Depression Scale (RCADS) was used to assess anxiety symptoms, and multilevel growth-curve analyses were performed. RESULTS: All subtypes of anxiety first showed a decrease in symptoms (beta for age ranged from -.05 to -.13, p < .0001), followed by a leveling off of the decrease, and a subsequent slight increase in symptoms (beta for age-squared ranged from .006 to .01, p < .0001) from middle adolescence (GAD, SoPh, SAD) or late adolescence (PD and OCD) onwards. This increase in anxiety symptoms could not be explained by a co-occurring increase in depression symptoms. Girls had more anxiety symptoms than boys, and this difference remained stable during adolescence (p < .0001). Gender differences were strongly attenuated by adjustment for symptoms of depression. CONCLUSIONS: The current study shows that, in the general population, anxiety symptoms first decrease during early adolescence, and subsequently increase from middle to late adolescence. These findings extend our knowledge on the developmental course of anxiety symptoms during adolescence. This is the first study to separate the development of anxiety symptoms from that of symptoms of depression.