Copenhagen Child Cohort Research Articles

Can the Whiteley Index be used to assess health anxiety in adolescents from the general population?

Health anxiety (HA) is characterized by worry about being or becoming ill. The Whiteley Index (WI) is a valid and frequently used measure for HA in adults. We examined item response distribution, floor and ceiling effects, and construct validity of four different one-factor models of the WI (an 8-item model, the widely used WI-7, a revised 7-item version (WI-7-R), and a 6-item version (WI-6-R)) in a population-based sample of adolescents, using data from the 16–17-year follow-up of the Copenhagen Child Cohort 2000 (N = 2521, 16–17 years old). Females generally scored higher on all eight WI items compared to males. Construct validity was examined by confirmatory factor analysis and hypothesis testing. The WI-7-R and WI-6-R both showed acceptable fits. All four models showed good internal consistency. Hypothesis testing showed good discriminant validity, as the hypotheses on positive correlations with anxiety, depression, and physical symptoms, as well as a negative correlation with health-related quality of life, were met for both the WI-7-R and WI-6-R. We advocate for the use of the WI-6-R, which focuses on core HA symptoms and excludes items concerning physical symptoms. The overall testing supports that the WI-6-R possesses valid psychometric properties for use with adolescents in the general population.

Exploring the course of functional somatic symptoms (FSS) from pre- to late adolescence and associated internalizing psychopathology – an observational cohort-study

BackgroundFunctional somatic symptoms (FSS), which commonly cannot be attributed to well-defined organic pathology, often co-occur with internalizing psychopathology and fluctuate throughout different life stages. We examined FSS courses throughout adolescence, and the association between preadolescent FSS, FSS severity and internalizing psychopathology at late adolescence.MethodsData from the Copenhagen Child Cohort (CCC2000) were utilized from assessments at ages 11–12 years (preadolescence; T0) and 16–17 years (late adolescence; T1). Self-report questionnaire and interview data on FSS, internalizing psychopathology, chronic medical conditions, and sociodemographic data from Danish national registers were available for 1285 youths. FSS courses were categorized into persistent (high FSS at T0 & T1), remission (high FSS only at T0), incident (high FSS only at T1) or no FSS (no FSS at T0 & T1). Multiple linear and multinomial logistic regressions were conducted to investigate the FSS/psychopathology association.Results1.8% of adolescents fell into the persistent FSS course group throughout adolescence. Higher preadolescent FSS predicted FSS (b = 0.07, p < .001), anxiety (b = 0.05, p < .001) and depression (b = 0.06, p < .001) at age 16/17, even after controlling for sex, parental education, a chronic medical condition and internalizing psychopathology in preadolescence. Persistent, incident, and remittent FSS courses were associated with significantly higher mean levels of anxiety and depression compared to the reference group (no FSS).ConclusionsFSS during pre- and late adolescence might increase and co-occur with anxiety and depression throughout adolescence, potentially due to shared underlying risk factors and processes.

GUNN DOTS IN CHILDREN AGED 11-12 YEARS FROM THE GENERAL COMMUNITY SAMPLE COPENHAGEN CHILD COHORT 2000 STUDY.

To study characteristics and associations of Gunn dots in a cohort of healthy children aged 11 to 12 years. As part of the Copenhagen Child Cohort 2000 Study, red-free fundus photographs were taken on 761 healthy children aged 11 to 12 years. The photographs were centered on the optic disk. Gunn dots were annotated and counted within a disk-centered circular grid of 6 mm diameter. Data were analyzed in relation to age, sex, axial length, and retinal nerve fiber layer thickness. Gunn dots were found in 716 of the 761 participants (94%). The majority of dots were located both inferior and superior to the optic disk, situated within a distance of 3 mm from its center. The median number of Gunn dots was 64 (range 0-574) in right eyes and 68 (range 0-532) in left eyes. Having more than the median number of Gunn dots in the right eye was associated with older age (odds ratio 2.12, 95% CI 1.56 to 2.89, P < 0.0001, adjusted for sex, axial length, and retinal nerve fiber layer thickness) and was less common among the children with a thinner retinal nerve fiber layer (odds ratio 0.40, 95% CI 0.26-0.60, P < 0.0001 comparing bottom and top quartiles). Gunn dots were visible in the majority of healthy children aged 11 to 12 years, and large numbers of dots were associated with a thicker nerve fiber layer and with older age, within the limited age range of 1 year. The clinical significance of Gunn dots is unknown. Their location at the vitreoretinal interface makes them a parameter of interest in the study of aging, epiretinal fibrosis, macular pucker and retinal detachment.

Comparison of prevalence and mental health problems across symptom frequency of self-reported symptoms of binge-eating disorder in a community sample of adolescents.

Binge-eating disorder (BED) and subthreshold BED (SBED) are prevalent in adults and associated with mental health problems including depression, non-suicidal self-injury, lower quality of life, and suicidality. There is solid evidence that binge-eating behaviors are also prevalent in adolescence, but knowledge about mental health in community adolescents with BED of different frequency thresholds is more limited. We aimed to investigate the prevalence and mental health problems associated with SBED of low frequency and/or limited duration compared with BED in a Danish community sample of adolescents. We included 2509 adolescents who completed the online survey of the 16-17-year follow-up of the Copenhagen Child Cohort (CCC2000), including items on BED symptoms approximating the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria, and items on mental health and quality of life. The 1-year prevalence of SBED was 2.7% (95% confidence interval [CI]: 2.0%-3.3%) with a male:female ratio of 1:3.7; comparable to previous findings on BED in the same sample. SBED was also comparable to BED concerning cross-sectional associations with overall mental health problems, lower health-related quality of life, depressive symptoms, and suicidal ideation, whereas no associations were seen with non-suicidal self-injury after Holm-Bonferroni correction. In both groups, thoughts and behaviors concerning food and weight interfered significantly with daily life. SBED and BED were equally prevalent in this adolescent community sample, and similarly associated with indicators of poor mental health. The findings indicate that community adolescents reporting symptoms approximating clinical criteria of BED need intervention irrespectively of symptom frequency or duration. This study adds knowledge to the field by comparing BED of low frequency and/or limited duration ("subthreshold BED," SBED) with full-syndrome BED in adolescents and showing that SBED in adolescence is both prevalent and associated with poor mental health to a similar extent as that of BED. Findings indicate that self-reported symptoms according to clinical criteria of SBED and BED alike constitute a public health problem and point to youngsters in need of intervention.

Can the bodily distress syndrome (BDS) concept be used to assess functional somatic symptoms in adolescence?

ObjectiveBodily Distress Syndrome (BDS) represents a new research concept for adult patients with various functional somatic syndromes. We evaluated the utility of the BDS research concept and the associated BDS-25-checklist as a screening tool for diverse functional somatic symptoms (FSS) in adolescence by investigating: 1) the psychometric and factorial structures of the checklist, 2) symptom cluster patterns and 3) illness classification and associations with emotional psychopathology and sociodemographic factors. MethodsThis cross-sectional study obtained data from the 16/17-year follow-up (N = 2542) of the general population Copenhagen Child Cohort 2000 (CCC2000). We used self-reported questionnaires to assess physical symptoms (the BDS-25 checklist), overall health (KidScreen), emotional psychopathology (Spence Children's Anxiety Scale; The Mood and Feelings Questionnaire), and illness worry (Whiteley-6 Index), and utilized data from Danish national registers to assess sociodemographic factors. ResultsThe BDS-25 checklist items displayed satisfactory psychometric data quality. Factor analyses revealed a similar four-factor model as reported in adults (factor loadings λ ≥0.5), representing distinct BDS symptom clusters: cardio-pulmonary, gastro-intestinal, musculoskeletal and general symptoms. Latent class analyses revealed a model with three latent classes, i.e. probable no to mild BDS, probable moderate, single-organ BDS and probable severe, multi-organ BDS, displaying acceptable class quality (Entropy = 0.904). Trend analyses revealed sociodemographic group differences across latent classes. Increased emotional psychopathology was associated with more pronounced BDS symptoms. ConclusionOur findings support the BDS concept with four symptom clusters and three illness severity groups (no BDS, single- organ and multi-organ BDS) to screen for FSS in adolescence.

Smoking in pregnancy is associated with increased adiposity and retinal arteriolar wall-to-lumen ratio in adolescence: The Copenhagen Child Cohort Study 2000.

To investigate the association between prenatal exposures and anthropometric data and cardiovascular risk factors including retinal arteriolar wall-to-lumen ratio in adolescence. This longitudinal observational study included all 1445 adolescents from the Copenhagen Child Cohort 2000 who attended the 2016-2017 examination. Outcome measures included retinal arteriolar wall-to-lumen ratio, height, body mass index, waist-to-hip ratio, body composition measured by bioimpedance, and blood pressure. Information on prenatal exposures (birth weight, gestational age, maternal smoking during pregnancy) as well as sex, parental age, household income and parental educational levels were obtained from national registries. Associations between exposures and outcome measures were analyzed using general linear models. Maternal smoking during pregnancy was associated with a higher retinal arteriolar wall-to-lumen ratio (0.004 or 1.9%, P=0.009) at age 16/17years, an association driven exclusively by the female participants (0.008 or 3.7%, P<0.0001). Maternal smoking during pregnancy was also associated to higher body-mass index (1.43kg/m2, P<0.0001), waist-to-hip ratio (0.02, P<0.0001) and fat mass index (0.93kg/m2, P<0.0001). Birth weight, gestational age, and parental age had no detectable impact on retinal arteriolar wall-to-lumen ratios. Prenatal exposure to tobacco smoking is associated with a higher risk of obesity and, predominantly in girls, to a greater retinal arteriolar wall thickness, which suggests that maternal smoking may induce an unfavorable cardiovascular and metabolic risk profile in the child.

Hair cortisol and self-perceived stress in adolescents with functional somatic disorders – a comparison with general population data

IntroductionFunctional somatic disorders (FSDs) are characterized by persistent and disabling physical symptoms that cannot be attributed to well-defined somatic disorders. In adolescents, the prevalence is around 4-10%. Evidence from adult populations suggests that cortisol plays a role in the development and perpetuation of FSDs, but little is known regarding adolescents. As cortisol accumulates in hair over time, hair cortisol concentration (HCC) is a promising new biomarker for long-term physiological stress. Moreover, adult studies have found associations between HCC levels and self-perceived stress.Objectives To compare HCC levels between adolescents with severe FSDs and adolescents from the general population. Furthermore, to investigate the association between HCC and self-perceived stress.MethodsThe data are retrieved from two projects: the AHEAD trial, including 91 15-19-year-old adolescents diagnosed with a severe FSD, and the Copenhagen Child Cohort 2000 (CCC2000), including data on 1455 16-17-year-old adolescents. Hair samples were collected for HCC analysis, and web-based questionnaires were used to asses self-perceived stress. Functional somatic symptoms were assessed with the Bodily Distress Syndrome (BDS) checklist.ResultsThe data have been collected and will be analysed and presented at the congress.ConclusionsThis study can contribute with knowledge about the potential role of cortisol in FSDs in adolescents, and whether self-perceived stress can be used as a marker for physiological stress measured by HCC. Treatments for adolescents with FSDs still need to be improved. The current study may help to understand whether future treatment strategies should include a greater focus on stress management.DisclosureNo significant relationships.

Infancy weight faltering and childhood neurodevelopmental disorders: a general population birth-cohort study.

While it is known that intrauterine growth restriction is associated with later mental disorders, it is still unclear whether similar associations exists for postnatal weight faltering, also known as 'failure to thrive' in infancy. This study examined the potential connection between infancy weight faltering and mental disorders diagnosed in childhood focusing specifically on neurodevelopmental disorders. The Copenhagen Child Cohort (CCC2000) was used to explore weight gain in infancy assessed by community health nurses. Data from the Danish national registries were used to quantify ICD-10 mental disorders diagnosed between birth and 12 years of age, as well as potential child and family confounders. Of 4.476 children with sufficient weight data, 339 (7.3%) children were diagnosed with a mental disorder in childhood. Both any (weight gain < -1SD) and severe infancy weight faltering (weight gain < -2SD) were associated with psychomotor delays, while severe infancy weight faltering was also associated with intellectual impairments. Notably, no significant associations were found between weight faltering and autism spectrum disorders or attention deficit hyperactivity disorders. Weight faltering in infancy may be an early marker of neurodevelopmental delays. This possibility should be considered when assessing infants with slow weight gain, to early identification and treatment of co-occurring neurodevelopmental disorders.

Cone photoreceptor density in the Copenhagen Child Cohort at age 16-17years.

To examine cone density in relation to gestational and morphological parameters in the Copenhagen Child Cohort (CCC2000). The macula was imaged using adaptive optics in 1,296 adolescents aged 16-17years. Axial length and distance visual acuity were determined. Absolute and angular cone photoreceptor density were analysed for an 80×80-pixel area, 2degrees temporal to the fovea. Association with axial length was analysed with linear regression. Correlation with visual acuity was described with a Pearson correlation coefficient. Associations of cone density with gestational parameters, maternal smoking, sex and age were analysed using multiple regression adjusted for axial length. Mean absolute cone density was 30,007cones/mm2 (SD±3,802) and mean angular cone density was 2,383cones/deg2 (SD±231). Peri- and postnatal parameters, sex and age had no statistically significant effect on cone density (p>0.05). Absolute cone density decreased with longer axial length (-2,855cones/mm2 per mm or -9.7% per mm, p<0.0001). For angular density, which included a correction for the geometrical enlargement of the eye with axial length, a decrease with axial length was detectable, but it was small (-20cones/deg2 per mm or -0.84% per mm, p=0.009). The decrease in cone density per unit solid angle with increasing axial length was small, less than 1 percent per mm, indicating that expansion of the posterior pole during the development of refraction takes place without a clinically significant loss of cones. Perinatal parameters, within the spectrum presented by the study population, had no detectable effect on cone density.

Precursors of self-reported subclinical hypomania in adolescence: A longitudinal general population study.

Symptoms of subclinical hypomania (SHM) are common in the general population of adolescents and young adults. SHM are most often transient yet might be risk markers of later bipolar disorder. The current study aimed to assess the clinical correlates of SHM at age 11 in the general population, examine the continuity of SHM from age 11-age 16 and explore the clinical precursors of age 16 SHM. As part of the Copenhagen Child Cohort 2000, 1,632 preadolescents participated in the examination of SHM and various clinical correlates at age 11, 893 were re-assessed for SHM at age 16 years. At age 11, SHM, psychotic experiences and depressive symptoms were assessed by semi-structured psychopathological interviews. Furthermore, the participants were diagnostically assessed by the Development and Well-Being Assessment and interviewed about sleep length. At age 16, SHM was assessed by self-report, using the Hypomania Checklist-32. Cannabis use occurring at age 15 or earlier was assessed at age 16. At age 11, SHM was associated with depressive disorders (Relative Risk [RR] = 2.96 [95% CI 1.26–6.96]), interview-based depressive symptoms (RR = 9.22 [5.93–14.34]), neurodevelopmental disorders (RR = 2.94 [1.66–5.20]), psychotic experiences (RR = 4.51 [2.90–7.01]) and insufficient sleep (RR = 2.10 [1.28–3.43]. In the longitudinal analyses, age 16 SHM was preceded by age 11 SHM (RR = 1.89 [1.02–3.49]), psychotic experiences (RR = 2.06, [1.28–3.33]), emotional disorders (RR = 1.77, [1.02–3.09]) and cannabis use (RR = 3.14, [1.93–5.10]), after mutual adjustment and adjustment for sex, and sociodemographic factors. In conclusion, age 11 SHM was statistically significantly associated with other types of psychopathology in cross-sectional analyses and showed some continuity with later self-reported SHM at age 16. Particularly early psychotic experiences and cannabis use stood out as independent precursors of self-reported SHM and might constitute important risk markers for the development of future SHM and bipolar disorder. An important potential caveat of the current study includes the self-report assessment of SHM.

Adolescents with functional somatic syndromes: Symptom profiles, illness perception, illness worry and attachment orientation

ObjectiveTo describe patterns of somatic symptoms, illness perception, illness worries and attachment in adolescents with functional somatic syndromes (FSS) in comparison with a population-based sample of adolescents. MethodsSelf-reported and clinical data were collected from two studies: 1) Adolescents aged 15-19 with multiple FSS of at least 1 year's duration (n = 91) from the trial AHEAD (Acceptance and Commitment Therapy for Health in Adolescents). 2) A sex-matched population-based sample of adolescents (n = 1573) derived from the 16-17-year follow-up of the Copenhagen Child Cohort 2000 (CCC2000), including a subgroup with high somatic symptom-load (n = 155). ResultsSymptom patterns were similar across groups, but somatic symptoms were approximately 2-3-fold more common in AHEAD compared to CCC2000, with the exception of neurological symptoms, i.e. ‘moving pain’, ‘unpleasant numbness or tingling sensation’ and ‘feeling of paresis’ which were 6.5-9.0 times higher in AHEAD. Adolescents from AHEAD reported considerably more negative illness perception and illness worry compared to both the CCC2000 sample and the high symptom subgroup. Levels of attachment avoidance and anxiety, respectively, were similar in AHEAD as compared with CCC2000 but lower compared to the high symptom subgroup of CCC2000. ConclusionSimilar symptom profiles in AHEAD and CCC2000 support the concept of a general (i.e. not syndrome-specific) factor for symptom development in FSS. Functional neurological symptoms may be useful indicators of clinical impairment. A high degree of negative illness perception and illness worry in youth may lead to healthcare seeking and should have a specific focus in assessment and treatment of youth with FSS.

Incidence of cilioretinal arteries in 11- to 12-year-old children and association with maternal smoking during pregnancy: the Copenhagen Child Cohort 2000 Eye Study.

To estimate the incidence of cilioretinal arteries in a Danish child cohort and associations with birth parameters. The population-based Copenhagen Child Cohort 2000 Eye Study examined 1406 children aged 11-12years. Colour fundus images of both eyes were graded for cilioretinal arteries in the three categories large temporal (defined as supplying the central macula), small temporal and nasal. Data on maternal smoking during pregnancy, gestational ageand birth weight were obtained from the Danish Medical Birth Registry. A total of 463/1338 (35%) children were found to have one or more cilioretinal arteries per child. Large temporal cilioretinal arteries were present in 280/1338 (21%) of children and were associated with tobacco smoking during pregnancy, being present in 70/246 (28%) of children with mothers who were smoking during pregnancy, but only in 191/990 (19%) of children whose mothers did not smoke during pregnancy (p=0.0022). After adjustments for potential confounders, the odds ratio of having one or more large temporal cilioretinal arteries was 1.72 (CI95% 1.19-2.47; p=0.0035) in the smoking versus none smoking category. No other associations with birth parameters were found. Cilioretinal arteries were present in more than one third of 11- to 12-year-old Danish children. Large temporal cilioretinal arteries were found in one fifth of children and were associated with maternal smoking during pregnancy. This finding suggests that the intrauterine environment may have an impact on the development of retinal vessels during foetal life.

Self-reported symptoms of binge-eating disorder among adolescents in a community-based Danish cohort-A study of prevalence, correlates, and impact.

Binge-eating disorder (BED) was established as a diagnosis in 2013 with the DSM-5 and has been included in the ICD-11 in 2018. In adulthood, BED is prevalent and correlated with somatic and mental health problems. Less is known about BED in adolescence, although this age period could represent a window of opportunity for early intervention. This study aimed to investigate the 1-year prevalence, correlates, and impact of BED symptoms in a community sample of adolescents. We included 1,404 girls and 1,105 boys from the 16-years-follow-up of the Copenhagen Child Cohort study, CCC2000. The adolescents self-reported on BED symptoms, weight-status, body perception, mental health problems, and self-rated impact of food and weight-related thoughts and behaviors. Information about socio-economic factors and hospital diagnosed psychiatric disorders were obtained from national registries. A total of 8.5% reported weekly overeating with loss of control (10.9% of girls, 4.8% of boys), and 2.6% (3.6% of girls, 1.2% of boys) reported symptoms consistent with BED according to the DSM-5. Regardless of sex, BED was correlated with concurrent overweight, body-dissatisfaction, low self-esteem, and mental health problems, especially emotional, but also with problems of behavior, inattention, and peer-relations, and with high self-rated impact on everyday life. Immigrant background and lower socio-economy were potential risk factors for BED in boys in this sample. BED was prevalent and correlated with mental health problems and overall impact among adolescents in this community sample, indicating the need for clinical attention and intervention towards binge-eating disorder in the adolescent period.

Healthcare Costs, School Performance, and Health-related Quality of Life in Adolescence Following Psychotic Experiences in Preadolescence: A Longitudinal Cohort Study.

Psychotic experiences (PEs) are common in the general population in preadolescence. The implications of PEs on socioeconomic outcomes, including educational attainment, are scarcely described. We aimed to estimate how preadolescent PEs were associated with later healthcare costs, school performance, and health-related quality of life (HRQoL) in adolescence. A total of 1607 preadolescents from the general population Copenhagen Child Cohort 2000 were assessed for PEs at age 11-12 years and followed up over 5 years using register-based data on mental and somatic healthcare costs, and school performance at age 16. Furthermore, HRQoL was assessed for a subsample of the children at age 16-17. We adjusted for perinatal and family sociodemographic adversities, prior parental mental illness and healthcare use, child IQ-estimate at age 11-12, and parent-rated general psychopathology of their child. PEs were associated with slightly poorer school performance. However, preadolescents with PEs more often reported HRQoL within the lowest 10th percentile (OR = 2.74 [95% CI 1.71-4.37]). Preadolescents who reported PEs had higher average total healthcare costs over the following 5 years. The costs for individuals with PEs were higher for mental healthcare services across primary to tertiary care, but not for somatic care. After adjustments, PEs remained independently associated with higher costs and poorer HRQoL, but not with poorer school performance. In conclusion, PEs are important in mental health screening of preadolescents and identify a group of young people with increased healthcare service-use throughout adolescence and who report poorer HRQoL in adolescence, over and above parent-rated general psychopathology of their child.

Retinal arteriolar wall-to-lumen ratios at 16–17 years in the Copenhagen Child Cohort 2000 Study

To study the thickness of retinal arteriolar walls in a population-based cohort of adolescents. This cross-sectional, observational study included 1217 participants aged 16-17 years from the Copenhagen Child Cohort 2000 Study. The wall thickness and lumen diameter of a major branch retinal arteriole were measured using adaptive optics imaging. The wall-to-lumen ratio was analyzed in relation to blood pressure and body composition variables using a general linear model. Overall in the study population, wall-to-lumen ratio was found to decrease by 0.49% per μm increase in arteriole diameter (P < 0.0001) and all subsequent analyzes were adjusted accordingly. The average outer and inner arteriole diameters were 117 ± 19 and 96.6 ± 18 μm (mean ± SD), corresponding to a wall-to-lumen ratio of 0.21 ± 0.024. There was no detectable difference between sexes. A higher wall-to-lumen ratio was associated with a higher BMI (+0.21% per kg/m, P = 0.0018), higher body fat percentage (+0.097% per 1% increase, P = 0.0052), wider hip circumference (+1.1% per 10 cm increase, P = 0.0006), wider waist circumference (+0.92% per 10 cm increase, P = 0.0009), higher SBP in girls (+1.1% per 10 mmHg increase, P = 0.0005), longer axial length (+0.70% per mm increase, P = 0.013), and younger age (+4.9% per year younger, P < 0.0001), adjusted for arteriole diameter, age, sex, and height. A higher retinal arteriolar wall-to-lumen ratio was associated with all registered indices of body fat proportion.

Psychotic experiences from preadolescence to adolescence: when should we be worried about adolescent risk behaviors?

Psychotic experiences (PE), below the threshold of psychotic disorder, are common in the general population. PE are associated with risk behaviors such as suicidality, non-suicidal self-injury (NSSI) and substance use. However, PE as specific or causal phenomena of these risk behaviors are still debated. We aimed to examine the longitudinal trajectories of PE from preadolescence to adolescence and their associated risk behaviors in adolescence. A total of 1138 adolescents from the Copenhagen Child Cohort 2000 were assessed for PE and risk behaviors (NSSI, suicide ideation and -attempts and substance use) at age 11 and 16years, along with measures of general psychopathology and depressive symptoms specifically. Self-reported impact of general psychopathology tended to be associated with more PE persistence. PE were associated with all risk behaviors in cross section at both follow-ups. Persistent PE from ages 11 to 16 and incident PE at age 16 were associated with risk behaviors at age 16, whereas remitting PE from age 11 to 16 were not. After adjustment for co-occurring depressive symptoms and general psychopathology, all associations were markedly reduced. After exclusion of preadolescents who already had expressed risk behavior at age 11, PE in preadolescence did not stand out as an independent predictor of incident adolescent risk behaviors. The current study suggests that PE in preadolescence and adolescence may not play a direct causal role regarding NSSI, suicidality, and substance use. However, PE are still useful clinical markers of severity of psychopathology and associated risk behaviors.

Evaluation of a screening algorithm using the Strengths and Difficulties Questionnaire to identify children with mental health problems: A five-year register-based follow-up on school performance and healthcare use.

Treatment of mental health problems (MHP) is often delayed or absent due to the lack of systematic detection and early intervention. This study evaluates the potential of a new screening algorithm to identify children with MHP. The study population comprises 2,015 children from the Copenhagen Child Cohort 2000 whose mental health was assessed at age 11-12 years and who had no prior use of specialised mental health services. A new algorithm based on the Strengths and Difficulties Questionnaire (SDQ) is utilised to identify MHP by combining parent-reported scores of emotional and behavioural problems and functional impairments. The screening is done on historical data, implying that neither parents, teachers nor health care professionals received any feedback on the screening status. The screening status and results of an IQ-test were linked to individual-level data from national registries. These national registers include records of each child's school performance at the end of compulsory schooling, their health care utilisation, as well as their parents' socio-economic status and health care utilisation. 10% of the children screen positive for MHP. The children with MHP achieve a significantly lower Grade Point Average on their exams, independently of their IQ-score, perinatal factors and parental characteristics. On average, the children with MHP also carry higher health care costs over a five-year follow-up period. The higher health care costs are only attributed to 23% of these children, while the remaining children with MHP also show poorer school performance but receive no additional health care. The results demonstrate that children with MHP and a poor prognosis can be identified by the use of the brief standardised questionnaire SDQ combined with a screening algorithm.

Low physical activity and higher use of screen devices are associated with myopia at the age of 16-17years in the CCC2000 Eye Study.

To determine the myopia prevalence in a Danish cohort aged 16-17years and its relation to physical activity and use of screen-based electronic devices. The Copenhagen Child Cohort 2000 Eye Study is a prospective, population-based, observational study. Information about use of screen devices and physical activity was obtained using questionnaires. Myopia was defined as non-cycloplegic subjective spherical equivalent refraction ≤-0.50 D in right eye. We included 1443 participants (45% boys) with a median age (±IQR) of 16.6years (±0.3). The prevalence of myopia was 25% (CI95% 23-28, n=360) with no differences between sexes (p=0.10). The odds ratio (OR) for myopia was 0.57 (CI95% 0.42-0.76, p=0.0002) in participants physically active 3-6hr/week (n=502) and 0.56 (CI95% 0.42-0.76, p=0.0002) if active >6hr/week (n=506), both compared with participants physically active <3hr/week (n=396). The use of screen devices >6hr/day was associated with increased OR for myopia compared with screen device use <2hr/day in both weekdays (OR=1.95, CI95% 1.16-3.30, p=0.012) and weekends (OR=2.10, CI95% 1.17-3.77, p=0.013). In this cohort of healthy 16-17-year olds, lower physical activity and more use of screen devices contributed significantly to the observed 25% prevalence of myopia with a roughly doubled risk of having myopia if physically active <3hr/week or if using screen devices >6hr/day. Our results support physical activity being a protective factor and near work a risk factor for myopia in adolescents.

The predictive validity of the Strengths and Difficulties Questionnaire in preschool age to identify mental disorders in preadolescence

The Strengths and Difficulties Questionnaire (SDQ) is a brief, widely used instrument to screen for mental health problems in children and adolescents. The SDQ predictive algorithms developed for the SDQ, synthesize information from multiple informants regarding psychiatric symptoms and their impact on daily life. This study aimed to explore the validity of the SDQ predictive algorithms used in preschool age to predict mental disorders in preadolescence. The study population comprises 1176 children from the Copenhagen Child Cohort 2000 (CCC2000) assessed at age 5–7 years by the SDQ and reassessed at 11–12 years with the Development and Well Being Assessment (DAWBA) for evaluation of ICD-10 mental disorders. Odds Ratios (ORs), sensitivities, specificities, positive predictive values (PPVs) and negative predictive values (NPVs) were calculated for the SDQ predictive algorithms regarding ICD-10 diagnoses of hyperkinetic-inattentive-, behavioural- and emotional disorders. Significant ORs ranging from 2.3–36.5 were found for the SDQ predictive algorithms in relation to the corresponding diagnoses. The highest ORs were found for hyperkinetic and inattentive disorders, and the lowest for emotional disorders. Sensitivities ranging from 4.5–47.4, specificities ranging from 83.0–99.5, PPVs ranging from 5.0–45.5 and NPVs ranging from 90.6–99.0 were found for the SDQ predictive algorithms in relation to the diagnoses. The results support that the SDQ predictive algorithms are useful for screening at preschool-age to identify children at an increased risk of mental disorders in preadolescence. However, early screening with the SDQ predictive algorithms cannot stand alone, and repeated assessments of children are needed to identify, especially internalizing, mental health problems.

Developmental and mental health characteristics of children exposed to psychosocial adversity and stressors at the age of 18-months: Findings from a population-based cohort study

BackgroundPrior research on adverse experiences in early childhood has mainly focused on at-risk populations while studies of unselected populations are scarce. This topic therefore remains to be elucidated in broader child populations. Accordingly, the aim of this study was to examine if and to what extent children from a general population sample are exposed to psychosocial adversity and stressors in early childhood and whether the development and mental health of children with and without such exposure differ at the age of 18-months. MethodsA random sample of the Copenhagen Child Cohort (CCC2000) comprising 210 children and their parents participated in the study when the children were approximately 18-months. Information on exposures was obtained from a semi-structured interview including the Mannheim Parent Interview (MPI) and classified in agreement with the Multiaxial Classification of Child and Adolescent Psychiatric Disorders (ICD-10), and the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood (DC: 0-3). Child development was assessed with the Bayley Scales of Infant and Toddler Development – Second Edition (BSID-II), while mental health was measured using the Child Behavior Check List (CBCL 1½-5). ResultsAmong the 210 children, 91 (43%) had been exposed to psychosocial adversity and persistent stressors. The exposed children differed from the non-exposed children by poorer cognitive development and behavioral regulation, as well as more attention problems and anxious/depressed symptoms. The children exposed to adverse caregiving environments were specifically more likely to have delayed cognitive development than the rest of the sample. ConclusionsIn a general population sample of children aged 18-months, exposure to psychosocial adversity and stressors was associated with poorer development and mental health in cognitive and affective domains. These findings highlight an avenue for further research with potential implications for early preventative practices.