Exploring the interplay between psychotic experiences, functional somatic symptoms and health anxiety in childhood and adolescence - A longitudinal cohort study

BACKGROUND

Similarities exist between contemporary explanatory models underlying psychosis development, functional somatic symptoms, and health anxiety. The current study aimed to examine the potential interplay between psychotic experiences (and alternate measures of anomalous self-experiences and aberrant attribution of salience) and functional somatic symptoms on the outcome of health anxiety in youths.

METHODS

In a prospective general-population birth cohort, the Copenhagen Child Cohort 2000 (CCC2000), data from two time-points were available for 1122 individuals. We assessed the associations between psychotic experiences and functional somatic symptoms with health anxiety both cross-sectionally at ages 11- and 16-years, and longitudinally from age 11 to 16. Further, we examined if there was an interaction between these two domains on the outcome of health anxiety using the interaction contrast ratio.

RESULTS

Functional somatic symptoms and psychotic experiences were strongly cross-sectionally associated with health anxiety at both ages 11 and 16, even after adjustment for general psychopathology. In the longitudinal analyses, functional somatic symptoms, and psychotic experiences at age 11 were not individually associated with health anxiety at age 16 but having both functional somatic symptoms and psychotic experiences was: odds ratio 3.90, 95%CI 1.7-8.9, with suggestion of evidence for interaction beyond the additive effects. This association was attenuated after adjustment for general psychopathology: odds ratio 2.6, 95 % CI 1.0-6.4.

CONCLUSION

The strong associations between the domains support the idea of possible overlapping mechanisms underlying psychotic experiences, functional somatic symptoms, and health anxiety.

Hair cortisol and self-perceived stress in adolescents with multi-system functional somatic disorders

BACKGROUND

Long-term stress causing altered hypothalamic-pituitary-adrenal (HPA) axis dynamics with cortisol dysfunction may be involved in the pathophysiology of functional somatic disorders (FSD), but studies on adolescents with multi-system FSD are lacking. Therefore, we investigated: 1) whether hair cortisol concentration (HCC) differentiates adolescents with multi-system FSD from a) a population-based sample and b) a subgroup derived from the sample reporting a high physical symptom load, and 2) whether FSD population HCC is associated with primary symptom presentations and self-perceived stress.

METHODS

We used data from a clinical sample with multi-system FSD (N = 91, age 15-19 years) and a population-based sample (N = 1,450, age 16-17 years) including a subgroup with top 10% total scores on physical symptoms (N = 147). Density plots and multiple linear regression were applied to compare HCC between groups. In the clinical sample, multiple linear regression was employed to assess the association between HCC and primary symptom clusters and self-perceived stress.

RESULTS

Median HCC was lower in the clinical sample than in the population-based sample (β = 0.80 (95%CI: 0.66, 0.97)), but not significantly different from median HCC in the derived subgroup (β = 0.84 (95%CI: 0.66, 1.07)). In the clinical sample, HCC was not significantly associated with primary symptom clusters (F(2, 82) = 0.13, p = 0.88) or self-perceived stress (F(4, 83) = 1.18, p = 0.33).

CONCLUSION

Our findings indicate that HCC is lowered in adolescents with multi-system FSD but not significantly associated with primary symptom presentations or self-perceived stress. Future studies including multiple measures of HPA axis dynamics alongside psychological measures may further elucidate the role of long-term stress in FSD.

TRIAL REGISTRATION

The AHEAD study was pre-registered at ClinicalTrials.gov (NCT02346071), 26/01/2015.

Predictors for and duration of hospitalization among children and adolescents with eating disorders

OBJECTIVE

The objective of this study was to investigate the predictive value of sex, age, body mass index (BMI), Eating Disorder Examination (EDE) score, social risk factors, and psychiatric comorbidities for hospitalization and hospitalization duration among children and adolescents suffering from eating disorders.

METHOD

This prospective cohort study involved 522 consecutive patients who had been referred to a specialized eating disorder unit between January 1, 2009 and December 31, 2015; participants were followed up until August 1, 2016 by medical records. We used regression analyses to evaluate the prognostic value of sex, age, BMI, EDE, eating disorder diagnoses, social risk factors, and psychiatric comorbidities concerning inpatient hospitalization and hospitalization duration.

RESULTS

We found that younger age, higher EDE global score, lower BMI percentile, anorexia nervosa, a higher number of social risk factors, and the presence of diagnosed self-harm increased the odds of being hospitalized, while being female and having a comorbid autism spectrum condition increased the duration of hospitalization. No other psychiatric comorbidity was found to significantly predict hospitalization or duration of hospitalization.

DISCUSSION

The odds of being hospitalized were predicted by the severity of anorexia nervosa and indicators of social risk factors in the family, whereas the duration of hospitalization was predicted by having a comorbid autism spectrum condition, indicating a difference between the factors affecting the risk of hospitalization and the factors affecting the duration of hospitalization. This calls for further exploration of tailored treatments for eating disorders.

PUBLIC SIGNIFICANCE STATEMENT

This study finds that hospitalization for an eating disorder is predicted by the severity of the illness, self-harm, and social risk factors. Duration of hospitalization is predicted by having a comorbid autism spectrum condition. These findings indicate that the treatment of eating disorders may require different treatment approaches depending on the presentation of the individual patient to reduce both the need for hospitalization and the length of inpatient stay.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

DISCUSSION

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.

PUBLIC SIGNIFICANCE

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.

[Not Available]

Anorexia nervosa (AN) is a mental disorder with the greatest incidence amongst women of the childbearing age. The prevalence of AN in pregnancy is marginal, yet the risk of exacerbation or reactivation is significant. Adverse perinatal complications of mental and physical nature pertain to both mother and child and through early diagnosis and monitoring during the perinatal period manageable. This preview describes the importance of enabling optimal perinatal care through a multidisciplinary management team.

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

PURPOSE

To investigate the association between prenatal exposures and anthropometric data and cardiovascular risk factors including retinal arteriolar wall-to-lumen ratio in adolescence.

METHODS

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.

RESULTS

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 16/17 years, 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 (1.43 kg/m², P < 0.0001), waist-to-hip ratio (0.02, P < 0.0001) and fat mass index (0.93 kg/m², P < 0.0001). Birth weight, gestational age, and parental age had no detectable impact on retinal arteriolar wall-to-lumen ratios.

CONCLUSION

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.

A psychometric investigation of the multiple-choice version of Animated Triangles Task to measure Theory of Mind in adolescence

The Animated Triangles Task (AT) is commonly used to measure Theory of Mind (ToM). AT can be scored by clinicians based on participants’ verbal responses (AT-verbal) or using a multiple-choice paradigm (AT-MCQ). This study aimed to evaluate the validity of the less time-consuming AT-MCQ. To do this, we examined agreement and correlations between the AT-MCQ and the original AT-verbal scores in 1546 adolescents from a population-based sample. As a supplementary analysis of known-groups validity, we examined if AT-MCQ was as sensitive as AT-verbal in detecting ToM-limitations in 54 adolescents with autism spectrum disorder (ASD), using register-data. The agreement between AT-verbal and AT-MCQ varied markedly across test items. Scores on the two scoring methods were weakly correlated. Both scoring methods weakly detected differences between adolescents with and without ASD in this population-based sample. Most participants had appropriate responses on both AT-MCQ and AT-verbal, which yielded overall acceptable agreement. However, the feasibility of using either scoring methods to measure ToM-limitations in adolescents from the general population is questionable.

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.

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

PURPOSE

To estimate the incidence of cilioretinal arteries in a Danish child cohort and associations with birth parameters.

METHODS

The population-based Copenhagen Child Cohort 2000 Eye Study examined 1406 children aged 11-12 years. 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.

RESULTS

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.

CONCLUSION

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.

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

PURPOSE

To examine cone density in relation to gestational and morphological parameters in the Copenhagen Child Cohort (CCC2000).

METHODS

The macula was imaged using adaptive optics in 1,296 adolescents aged 16-17 years. Axial length and distance visual acuity were determined. Absolute and angular cone photoreceptor density were analysed for an 80 × 80-pixel area, 2 degrees 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.

RESULTS

Mean absolute cone density was 30,007 cones/mm² (SD ± 3,802) and mean angular cone density was 2,383 cones/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 (-2,855 cones/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 (-20 cones/deg² per mm or -0.84% per mm, p = 0.009).

CONCLUSIONS

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.

Continuity of health anxiety from childhood to adolescence and associated healthcare costs: a prospective population-based cohort study

BACKGROUND

Severe health anxiety (HA) is characterized by excessive and impairing worry and preoccupation with health issues and can cause increased and unnecessary medical examinations. HA in childhood and adolescence is scarcely explored, hindering the potential for prevention and early intervention.

METHODS

HA was assessed in 1,278 children/youths at two time points at ages 11 and 16 years in a general population-based birth cohort. Register-based data on costs related to nonhospital-based primary and secondary somatic health services were obtained over the follow-up period. The presence of functional somatic symptoms, emotional disorders and chronic somatic illness at baseline were included as covariates.

RESULTS

High HA (top 10% score) at age 11 predicted high HA at age 16 (relative risk [RR] 2.03, 95% CI: 1.26-3.31). The group with persistent HA was small (n = 17, 1.3%), resulting in broad confidence intervals. The statistical effect of HA at age 11 on HA at age 16 was heavily reduced after adjustment for sex and all covariates (RR: 1.49, 95% CI: 0.85-2.60). In the adjusted model, somatic illness at age 11 (RR: 1.91, 95% CI: 1.22-2.98) and female sex (RR: 3.33, 95% CI: 2.01-5.50) were independently associated with HA at age 16. Persistent HA was associated with approximately doubled healthcare costs compared to the group with consistently low HA. Incident HA at age 16 was associated with increased costs over follow-up. The increased costs were not explained by chronic somatic illness.

CONCLUSIONS

A small subgroup of children had persistent high levels of HA from late childhood to adolescence and displayed increased healthcare costs. Female sex and chronic somatic disorders at age 11 were independent risk factors of HA at age 16. These findings provide potential means of early identification and of therapeutic levers. Further intervention development and evaluation are needed.

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.

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 16 years, 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.

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

PURPOSE

To determine the myopia prevalence in a Danish cohort aged 16-17 years and its relation to physical activity and use of screen-based electronic devices.

METHODS

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.

RESULTS

We included 1443 participants (45% boys) with a median age (±IQR) of 16.6 years (±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 3-6 hr/week (n = 502) and 0.56 (CI95% 0.42-0.76, p = 0.0002) if active >6 hr/week (n = 506), both compared with participants physically active <3 hr/week (n = 396). The use of screen devices >6 hr/day was associated with increased OR for myopia compared with screen device use <2 hr/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).

CONCLUSION

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 <3 hr/week or if using screen devices >6 hr/day. Our results support physical activity being a protective factor and near work a risk factor for myopia in adolescents.

Five-Year Change in Choroidal Thickness in Relation to Body Development and Axial Eye Elongation: The CCC2000 Eye Study

Purpose

We describe changes in choroidal thickness from age 11 to 16 years and its association with ocular biometrics and body development.

Method

In this longitudinal, population-based observational study, choroidal thickness was measured subfoveally and 1- and 3-mm temporal thereof using enhanced depth imaging spectral domain optical coherence tomography. Analyses were stratified by sex and adjusted for age and the time of day that the scan was performed.

Results

The study included 687 participants (304 boys). Median (interquartile range [IQR]) age was 11.5 (0.6) years at baseline and 16.6 (0.3) years at follow-up. Mean increase in choroidal thickness was 33, 27, and 11 μm at the three respective locations. The subfoveal choroid thickened less in eyes whose axial length increased more (boys, β = -85 μm/mm; 95% confidence interval [CI], -104 to -66, P < 0.0001; girls, β = -105 μm/mm; 95% CI, -121 to -89, P < 0.0001) and in eyes with a more negative refractive development (boys, 11 μm/diopters [D]; 95% CI, 4.0 to 18, P = 0.0022; girls, 22 μm/D; 95% CI, 16 to 27, P < 0.0001). Subfoveal choroidal thickness increased less in girls who underwent early puberty (Tanner stage 4 vs. 1; -39 μm' 95% CI, -72 to -5.9, P = 0.021) and who had a longer baseline axial length (β = -8.6 μm/mm; 95% CI, -15 to -2.7, P = 0.0043), and more in girls who grew taller (β = 0.9 μm/cm; 95% CI, 0.1 to 1.7, P = 0.026).

Conclusions

The choroid increased in thickness from age 11 to 16 years. The increase was greater in girls with later sexual maturation and smaller in eyes that added more axial length and had a relatively negative refractive development.

Problems of feeding, sleeping and excessive crying in infancy: a general population study

OBJECTIVE

To study regulatory problems (RPs) of feeding, sleeping and excessive crying in infancy, and explore the influence of maternal mental health problems and parent-child relationship problems.

DESIGN AND SETTING

Data were collected in the general child health surveillance delivered to infant families by community health nurses (CHNs). Information on CHNs' assessments and conclusions were obtained on 2598 infants and merged with data from national registers. Descriptive statistics and logistic regression models were used to study RPs in early and late infancy, and the influences due to child, family and parent-child relationship problems.

RESULTS

Combined RPs (C-RPs), defined as two or more simultaneous problems of feeding, sleeping or excessive crying, was identified in 2.9% and 8.6% of the population between age 2-6 and 8-11 months, respectively. Low maternal schooling and immigrant parents were associated with an increased risk of late C-RPs, but RPs in early infancy stand out as the main predictor of late C-RPs OR 3.4 (95% CI 1.8 to 6.6), and the effect of early maternal mental health problems and parent-child relationship problems seem to be mediated by early C-RPs.

CONCLUSIONS

Combined problems of feeding, sleeping or excessive crying may exist throughout infancy independently of exposures to maternal mental health problems and parent-child relationship problems. The results indicate that infants with RPs exceeding age 2 months need special attention, in clinical as well as community settings. Suggested intervention includes specific guidance to the parents to help them understand and regulate their infant's sensitivity and reactions.

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

BACKGROUND

Prior 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.

METHODS

A 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).

RESULTS

Among 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.

CONCLUSIONS

In 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.

Weight trajectories and disordered eating behaviours in 11- to 12-year-olds: A longitudinal study within the Danish National Birth Cohort

OBJECTIVE

To examine how childhood weight trajectories are associated with disordered eating behaviours (DEBs) in early adolescence.

METHODS

Self-reports on DEBs (fasting, purging, and binge eating) were obtained from 18,337 children in the 11-year follow-up of the Danish National Birth Cohort. For this population, birth register information on gestational age and birth weight was categorized into the following: small, appropriate, and large for gestational age. Prospective parent-reported height and weight data at child ages 1 and 7 years were dichotomized using standardized cut-offs into non-overweight and overweight. A 12-category weight trajectory variable was created, and the associations between weight trajectory and DEBs were estimated using logistic regression.

RESULTS

In total, 7.0% 11- to 12-year olds reported DEBs. Compared with children born appropriate for gestational age and being non-overweight at age 1 and 7 years, children born small for gestational age and who were overweight at age 1 and 7 years had a very high risk of disordered eating (OR 7.00; CI [2.57, 19.40]). The statistical analyses revealed, however, that overweight at age 7 years was the main contributor and independently of trajectory increased the risk of disordered eating at age 11-12 years significantly (OR 3.16 CI [2.73, 3.65]).

CONCLUSION

Overweight not in the first year of life, but at age 7 years was more predictive for DEBs.

Small Hard Macular Drusen and Associations in 11- to 12-Year-Old Children in the Copenhagen Child Cohort 2000 Eye Study

Purpose

To assess the prevalence and associations of small hard drusen in a child cohort.

Methods

Cross-sectional study of 11- to 12-year-old Danish children from the population-based Copenhagen Child Cohort 2000 Eye Study. Fovea-centered, 45° color images of both eyes were graded for macular drusen (within one optic-disc-rim-to-fovea distance of the foveal center) and for extramacular drusen. Analyses tested for associations between drusen and anthropometric measures including choroidal thickness.

Results

Gradable fundus images from both eyes were available for 1333 children (640 boys, 693 girls) with a mean (SD) age of 11.7 (0.40) years. One or more small hard macular drusen (diameter <63 μm) were present in 82 (6.2%) right eyes and 82 (6.2%) left eyes and in 147 (11.0%) subjects. Four children (0.30%) had 20 or more small hard macular drusen in one or both eyes. Extramacular small hard drusen were present in 10.7% of children, and 19% of children had such drusen anywhere. The odds for having one or more small hard macular drusen increased with subfoveal choroidal thickness with an odds ratio of 1.15 (95% confidence interval, 1.03-1.28; P = 0.013) per 50-μm thicker choroid, adjusted for age and sex. The association with choroidal thickness was also present for extramacular drusen.

Conclusions

Having one or more small hard macular drusen was common in 11- to 12-year old children and it was associated with a thicker subfoveal choroid. Few children had many small hard drusen. There is no apparent clinical impact of small hard drusen in childhood.

Visual acuity and amblyopia prevalence in 11- to 12-year-old Danish children from the Copenhagen Child Cohort 2000

PURPOSE

To evaluate the prevalence of amblyopia and associated biometric factors in Danish children.

METHODS

Determination of best-corrected visual acuity (BCVA) using ETDRS charts, non-cycloplegic subjective refractioning guided by automated refractometry, axial length and corneal curvature, fundus photography and optical coherence tomography (OCT) in 1335 children from the population-based Copenhagen Child Cohort 2000 (CCC2000) Eye Study. Birth data were obtained from the Danish Medical Birth Registry.

RESULTS

The mean (±SD) age of children was 11.7 (±0.4) years, and 47% were boys. Amblyopia prevalence was 1.5 (95% CL 0.8-2.2) %. Unilateral amblyopic eyes [BCVA < 80 ETDRS letters (0.8 snellen) and ≥2 lines difference between the eyes] was 0.6 (95% CL 0.3-1.0) mm shorter, 1.34 (95% CL 0.30-2.37) D more hyperopic and had 0.79 (95% CL 0.14-1.44) D more astigmatism compared with fellow eyes. Compared with the right eyes of the non-amblyopic children, unilateral amblyopic eyes were 1.0 (95% CL 0.5-1.6) mm shorter, 2.48 (95% CL 1.11-3.86) D more hyperopic, 1.09 (95% CL 0.43-1.75) D more astigmatic and had a 47 (95% CL 13-81) μm thicker subfoveal choroid.

CONCLUSION

Amblyopia was found in 1.5% of Danish children born 22 years after the inception of the nationwide preschool visual screening programme. Amblyopia was associated with anisometropia, astigmatism, a thicker subfoveal choroid and a history of childhood strabismus.

[Standardised measuring the health of infants and toddlers in community health services]

Standardised measures are needed in the general child health surveillance. A standardised record with manualised guidelines have been created for use in the existing services of community health nurses, to collect epidemiological data and improve the quality of regional child health surveillance. The record has been used since 2000, and currently one third of the Danish child population is included. Research findings suggest targets of intervention towards risk trajectories of overweight, weight faltering, eating problems and neuro-developmental disorders.

[Overweight and eating disorders in patients with attention deficit hyperactivity disorder]

Recent studies have generally found an increased prevalence of overweight and obesity among children, adolescents and adults with attention deficit hyperactivity disorder (ADHD), and the latest research suggests, that ADHD is also associated with problematic eating behaviour and eating disorders. The pathways of these associations are still up for discussion, but both psychological and biological factors are important aspects. There is further-more a good theoretical basis for the assumption, that active drug treatment of ADHD may minimise the risk of overweight. However, existing research is predominantly based on small, selected cross-sectional studies.

Parental characteristics in association with disordered eating in 11- to 12-year-olds: A study within the Danish National Birth Cohort

We examined the association between parental characteristics and disordered eating among 11- to 12-year-olds within the Danish National Birth Cohort. Frequency of fasting, purging, and binge eating was obtained by self-report from 37,592 children and combined into a measure of disordered eating (no, monthly, and weekly). Information on parental characteristics was obtained during pregnancy, from the 7-year follow-up, and by linkage to population registers. Data were analysed using multinomial logistic regression models with robust standard errors. In total, 3.1% reported weekly and 4.1% reported monthly disordered eating. Parental young age, low educational level, and overweight/obesity were associated with disordered eating. The relative risk ratios for, respectively, weekly and monthly disordered eating according to maternal eating disorder were 1.01 [0.75, 1.37] and 1.09 [0.84, 1.42]. Disordered eating is common among children and is associated with several parental characteristics. We found social inequality in disordered eating, but our data did not support an association with maternal eating disorder.

Early Predictors of Eating Problems in Preadolescence-A Prospective Birth Cohort Study

PURPOSE

The epidemiology of childhood eating problems is far from being fully described. The present study aims to explore early predictors of eating behavior problems in preadolescence.

METHODS

The study sample comprised 1,939 children from the birth cohort study, the Copenhagen Child Cohort (CCC2000). Logistic regression models were used to investigate associations among infancy health, developmental and relational factors, maternal mental health problems, socioeconomic factors, parental reported eating behavior patterns in preschool age and eating behavior problems in preadolescence.

RESULTS

A number of factors expressing socioeconomic disadvantage across childhood were associated with an increased risk of eating behavior problems at age 11-12 years. In addition, overeating patterns at age 5-7 years predicted restrained eating in preadolescence (odds ratio [OR] = 2.77; 95% confidence interval [CI] = 1.13-6.77; p = .03), with overweight at age 11-12 years and low annual household income as strong explanatory factors (OR = 4.79; 95% CI = 2.81-8.17; p < .0001 and OR = 2.06; 95% CI = 1.19-3.58; p = .02, respectively). No significant associations between perinatal, early child- and relational factors, or maternal mental disorder and eating behavior problems in preadolescence were found.

CONCLUSIONS

Our results suggest that overeating at age 5-7 years is prospectively associated with restrained eating in preadolescence, with contemporaneous socioeconomic disadvantages and overweight as strong explanatory factors. Our findings might reflect successful public health interventions toward childhood obesity or might reflect a developmental course of problematic eating fluctuating between over- and undereating. Future studies should focus on the possible pathways from overeating to restrained eating and more severe eating pathology, including possible negative side effects of otherwise successful interventions aimed at reducing childhood obesity.

Spatial ecology of coastal Atlantic cod Gadus morhua associated with parasite load

Acoustic tags and receivers were used to investigate the spatial ecology of coastal Atlantic cod Gadus morhua (n = 32, mean fork length: 50 cm, range: 33-80 cm) on the Norwegian Skagerrak coast in 2012. Monthly home ranges (HR), swimming activity and depth use varied considerably among individuals and through the months of June, July and August. HR sizes for the period ranged from 0.25 to 5.20 km2 (mean = 2.30 km2. Two thirds of the tagged G. morhua were infected with black spot disease Cryptocotyle lingua parasites; these fish had larger HRs and occupied deeper water compared with non-infected fish. The infected fish also tended to be more active in terms of horizontal swimming. From an ecological and evolutionary perspective, any environmental change that modifies G. morhua behaviour may therefore also alter the parasite load of the population, and its conservation and fishery status.

Infancy predictors of hyperkinetic and pervasive developmental disorders at ages 5-7 years: results from the Copenhagen Child Cohort CCC2000

BACKGROUND

Epidemiological studies infancy predictors of mental disorders are scarce.

METHODS

The study is part of a longitudinal birth-cohort study, The Copenhagen Child Cohort CCC2000. Infant mental health and development and mother-infant relations were assessed by community health nurses from birth to age 10 months. Data on the perinatal period were obtained from Danish National Registers. Mental health outcome at age 5-7 years was investigated in 1,585 children who were assessed by the Developmental and Well-Being Assessment (DAWBA) and diagnosed according to the ICD-10.

RESULTS

Predictors of autism spectrum disorders were problems of oral-motor development OR 5.02 (95% CI: 1.63-15.42) and overall development OR 4.24 (95% CI: 1.35-13.33). A deviant pattern of activity and interests were predictive of autism spectrum disorder, OR 5.34 (95% CI 1.45-19.70) and hyperkinetic disorder, OR 4.71 (95% CI: 1.28-17.39). Hyperkinetic disorder was furthermore predicted by mother-infant relationship problems, OR 8.07 (95% CI: 2.90-22.47). The significant associations between infant developmental problems and autism spectrum disorders persisted in multiple logistic regression analyses controlled for maternal psychological problems and mother-infant relationship problems, OR 3.21 (95% CI: 1.09-9.45). Mother-infant relationship problems remained strongly associated to hyperkinetic disorders in the multivariate analyses controlled for child development problems and maternal psychological problems, OR 5.20 (95% CI: 1.55-17.47). No significant infancy predictors were found regarding emotional and behavioural disorders at age 5-7 years.

CONCLUSION

Predictors of autism spectrum/pervasive developmental disorders and hyperkinetic disorders at child age 5-7 years were identified between birth and child age 10 months in community health settings. The study results suggest potential areas of early preventive intervention, which have to be further explored regarding the psychometric qualities of the identification of infants at risk, and concerning methods to handle and intervene towards these children in the general child health surveillance.

[Wilson disease often debuts with psychiatric symptoms]

We present a case of a 17-year-old girl initially suspected of having a psychiatric disease within the affective spectrum. However, thorough evaluation of the overall symptomatology, and a combination of repeated physical examinations and paraclinical testing led to the diagnosis of Wilson disease. This case emphasizes the importance of a broad diagnostic approach to psychiatric patients.

Infant behaviors are predictive of functional somatic symptoms at ages 5-7 years: results from the Copenhagen Child Cohort CCC2000

OBJECTIVE

To investigate infancy predictors of impairing functional somatic symptoms (FSS) at child ages 5-7 years with a focus on problems with feeding, sleep, and tactile reactivity.

STUDY DESIGN

This study is part of a longitudinal birth cohort study, Copenhagen Child Cohort CCC2000. Child health, development, and functioning were assessed by community health nurses at 4 home visits from birth to age 10 months. FSS at ages 5-7 years were measured by the Soma Assessment Interview in 1327 children. Sociodemographic data and information on maternal psychiatric illness were obtained from the Danish National Registers.

RESULTS

Multiple logistic regression analysis controlled for maternal psychiatric illness and annual household income revealed that combined infancy regulatory problems (ie, at least 2 of 3 problems of feeding, sleeping, or tactile reactivity during the first 10 months of living) predicted impairing FSS at 5-7 years (aOR = 2.9, 95% CI: 1.3-6.6). Maternal psychiatric illness during the child's first year of living was also associated with later child FSS (aOR = 7.1, 95% CI: 1.8-27.8).

CONCLUSION

Regulatory problems may be an early marker of disturbed sensory reactivity in young children, which together with maternal psychiatric problems, point to possible early risk mechanisms of impairing FSS in childhood.

Are low but statistically significant levels of genetic differentiation in marine fishes 'biologically meaningful'? A case study of coastal Atlantic cod

A key question in many genetic studies on marine organisms is how to interpret a low but statistically significant level of genetic differentiation. Do such observations reflect a real phenomenon, or are they caused by confounding factors such as unrepresentative sampling or selective forces acting on the marker loci? Further, are low levels of differentiation biologically trivial, or can they represent a meaningful and perhaps important finding? We explored these issues in an empirical study on coastal Atlantic cod, combining temporally replicated genetic samples over a 10-year period with an extensive capture-mark-recapture study of individual mobility and population size. The genetic analyses revealed a pattern of differentiation between the inner part of the fjord and the open skerries area at the fjord entrance. Overall, genetic differentiation was weak (average F(ST)  = 0.0037), but nevertheless highly statistical significant and did not depend on particular loci that could be subject to selection. This spatial component dominated over temporal change, and temporal replicates clustered together throughout the 10-year period. Consistent with genetic results, the majority of the recaptured fish were found close to the point of release, with <1% of recaptured individuals dispersing between the inner fjord and outer skerries. We conclude that low levels of genetic differentiation in this marine fish can indeed be biologically meaningful, corresponding to separate, temporally persistent, local populations. We estimated the genetically effective sizes (N(e) ) of the two coastal cod populations to 198 and 542 and found a N(e) /N (spawner) ratio of 0.14.

Quantitative genetic parameters for wild stream-living brown trout: heritability and parental effects

Adaptability depends on the presence of additive genetic variance for important traits. Yet few estimates of additive genetic variance and heritability are available for wild populations, particularly so for fishes. Here, we estimate heritability of length-at-age for wild-living brown trout (Salmo trutta), based on long-term mark-recapture data and pedigree reconstruction based on large-scale genotyping at 15 microsatellite loci. We also tested for the presence of maternal and paternal effects using a Bayesian version of the Animal model. Heritability varied between 0.16 and 0.31, with reasonable narrow confidence bands, and the total phenotypic variance increased with age. When introducing dam as an additional random effect (accounting for c. 7% of total phenotypic variance), the level of additive genetic variance and heritability decreased (0.12-0.21). Parental size (both for sires and for dams) positively influenced length-at-age for juvenile trout--either through direct parental effects or through genotype-environment correlations. Length-at-age is a complex trait reflecting the effects of a number of physiological, behavioural and ecological processes. Our data show that fitness-related traits such as length-at-age can retain high levels of additive genetic variance even when total phenotypic variance is high.

New Danish reference values for height, weight and body mass index of children aged 0-5 years

AIM

To derive new reference values for height, weight and body mass index (BMI) of children aged 0-5 years in Denmark and to compare them with the national reference from the 1970s and the 2006 WHO standard.

METHODS

The height and weight of 4105 healthy singleton children born in 1995 were obtained from a cohort study. Children were measured at birth and at seven regular health examinations by a general practitioner up to 5 years of age. Generalized additive models for location, scale and shape were used to construct percentile curves.

RESULTS

Mean length, weight and BMI at birth and during the first months of life increased significantly, but the differences diminished thereafter, and at 1 year BMI had decreased. In boys, weight and BMI had decreased by 2 years of age but had increased, together with height, at 5 years. Children were taller, heavier and had a higher BMI than that referred to in the WHO standard.

CONCLUSION

New references for length or height, weight and BMI by age were constructed for children in Denmark. Since the 1970s, weight, length and BMI at birth increased, and growth during the first year of life appears to be healthier.

Functional somatic symptoms and associated impairment in 5-7-year-old children: the Copenhagen Child Cohort 2000

Research on somatisation or functional disorders, characterised by the subjective report of physical symptoms in the absence of clear physical pathology, in young children is limited. This study investigates the distribution, types and co-occurrence of parent-reported functional somatic symptoms (FSS) and their impairment in a population-based sample of Danish 5-7-year-old children. Data were obtained from a 5-7-year follow-up of the Copenhagen Child Cohort 2000. The entire study population included 3,000 randomly sampled children from the cohort. Among these FSS measures were obtained for 1,327 children. The newly introduced parent interview, the soma assessment interview, was used to assess the child's FSS. Impairing symptoms were defined as FSS that caused substantial discomfort, impairment of everyday life, absence from day-care or school and/or help-seeking in the health care system. The 1-year prevalence of any FSS was 23.2% (N = 308) and higher in girls than boys (27.6 vs. 18.8%, P < 0.0001). Impairing FSS were found in 4.4% (N = 58). Pain complaints, i.e. limb pain, headache and abdominal pain, were the most frequently reported FSS. Among the 308 children with FSS, 66 (21.4%) presented with two or more of these functional pain complaints, while 15 (4.9%) had all three types. The findings indicate that FSS are common health complaints in 5-7-year-old children. A subgroup with impairing FSS with a likely need of clinical intervention was identified. This suggests that a somatisation pattern may start early in life and call for future studies to include associated impairment in the investigation of childhood FSS.

Sibling-size variation in brown trout Salmo trutta in relation to egg size and stream size

Sibling-size variation (SSV), estimated as the coefficient of variation of egg size, was investigated for 13 populations of brown trout Salmo trutta. SSV was negatively correlated with mean egg size both at the population and individual levels. After correction for the effect of mean egg size, SSV was also negatively correlated with stream size. These results provide new information about how salmonid SSV can vary at different ecological scales (individual, population and region). The results are discussed in light of competing theories for explaining SSV: (1) the passive effect hypothesis, stating that egg size variation follows passively from selection on egg size and (2) the bet-hedging hypothesis, stating that high SSV is adaptive in unpredictable environments.

Can a general health surveillance between birth and 10 months identify children with mental disorder at 1(1/2) year? A case-control study nested in cohort CCC 2000

Mental health surveillance in infancy was studied in an existing child health surveillance programme with child psychiatric disorder at 1(1/2) year as the outcome.

METHODS

Children considered of concern by community health nurses were cases in a case control study nested in the Copenhagen Child Cohort (CCC 2000). Outcome was mental health status at 1(1/2) year assessed by clinical and standardised strategies, including videotape recordings, parent interviews and the instruments: CBCL 1(1/2)-5, ITSCL, CHAT, Bayley Scales of Infant Development II, PC ERA and PIR-GAS.

RESULTS

The positive predictive value of concern in the first 10 months of living was 24% (CI 17.0-31.9), the negative predictive value was 85% (CI 77.9-89.6) and the sensitivity was 56% (CI 42.4-69.0). Concern about development was significantly associated with the child having a neuro-developmental disorder at 1(1/2) year, and concern about mother-child relationship was associated with emotional, behavioural, eating, and sleeping disturbances.

CONCLUSIONS

A general health surveillance program seems to have potentials to identify infants at risk for mental health problems provided standardised measures and specific training of the involved health professionals.

Predictors (0-10 months) of psychopathology at age 11/2 years - a general population study in The Copenhagen Child Cohort CCC 2000

BACKGROUND

Epidemiological studies of mental health problems in the first years of life are few. This study aims to investigate infancy predictors of psychopathology in the second year of life.

METHODS

A random general population sample of 210 children from the Copenhagen Child Birth Cohort CCC 2000 was investigated by data from National Danish registers and data collected prospectively from birth in a general child health surveillance programme. Mental health outcome at 1(1/2) years was assessed by clinical and standardised measures including the Child Behavior Check List 1(1/2)-5 (CBCL 1(1/2)-5), Infant Toddler Symptom Check List (ITSCL), Checklist for Autism in Toddlers (CHAT), Bayley Scales of Infant Development (BSID II), Mannheim Eltern Interview (MEI), Parent Child Early Relational Assessment (PC ERA) and Parent Infant Relationship Global Assessment Scale (PIR-GAS), and disordered children were diagnosed according to the International Classification of Diseases (ICD-10) and Diagnostic Classification Zero to Three (DC: 0-3).

RESULTS

Deviant language development in the first 10 months of life predicted the child having any disorder at 1(1/2) years, OR 3.3 (1.4-8.0). Neuro-developmental disorders were predicted by deviant neuro-cognitive functioning, OR 6.8 (2.2-21.4), deviant language development, OR 5.9 (1.9-18.7) and impaired social interaction and communication, OR 3.8 (1.3-11.4). Unwanted pregnancy and parents' negative expectations of the child recorded in the first months of the child's life were significant predictors of relationship disturbances at 1(1/2) years.

CONCLUSIONS

Predictors of neuro-developmental disorders and parent-child relationship disturbances can be identified in the first 10 months of life in children from the general population.

[Markers of mental health problems based on public health nurses' assessments of 0- to 1-year-old children: the Copenhagen County Child Cohort 2000]

INTRODUCTION

Epidemiological studies of psychopathology in the first years of life are few, and the associations between mental health problems in infancy and toddler age and mental health disturbances later in life have not been systematically investigated. This study aimed to investigate whether markers of mental health problems can be identified in the first years of life and thus increase the scientific foundation for prevention early in childhood.

METHODS

The population studied was a birth cohort of children born in Copenhagen County in year 2000, the Copenhagen County Child Cohort 2000 (CCCC 2000), which has been followed prospectively from birth. Mental and physical health are described at baseline based on Danish national registers and standardised records from home visits made by public health nurses.

RESULTS

CCCC 2000 covers 6,090 children, of whom 5,624 (92%) have been described in health reports by public health nurses. In 13% of the cohort children, the general development was recorded as not normal, and in 12% language development was deviant. Problems with eating and sleeping were found frequently, in 30% and 20% of the children, respectively, and in 10% of the cases disturbances in the mother-child relationship were recorded.

CONCLUSION

The first results from CCCC 2000 show that risk factors and markers of mental disturbances can be identified in at least 10% of children in the general population. The validity of these results is currently being investigated in follow-up studies of CCCC 2000.

[The growth pattern of 0- to 1-year-old Danish children screened by public health nurses: the Copenhagen County Child Cohort 2000--secondary publication]

Use of invalid growth curves can result in false conclusions about the growth and thriving of children. We describe the current growth pattern of 0- to 1-year-old children in Denmark compared to national and international references. The data consist of weights and lengths of 6,090 children born in the County of Copenhagen in the year 2000. The updated growth curves differ markedly from the growth references and show a changed growth pattern of Danish infants, with a more rapid increase in weight during the first six months of life. The curves represent an updated alternative for monitoring growth in Danish infants.

Failure to thrive: the prevalence and concurrence of anthropometric criteria in a general infant population

BACKGROUND

Failure to thrive (FTT) in early childhood is associated with subsequent developmental delay and is recognised to reflect relative undernutrition. Although the concept of FTT is widely used, no consensus exists regarding a specific definition, and it is unclear to what extent different anthropometric definitions concur.

OBJECTIVE

To compare the prevalence and concurrence of different anthropometric criteria for FTT and test the sensitivity and positive predictive values of these in detecting children with "significant undernutrition", defined as the combination of slow conditional weight gain and low body mass index (BMI).

METHODS

Seven criteria of FTT, including low weight for age, low BMI, low conditional weight gain and Waterlow's criterion for wasting, were applied to a birth cohort of 6090 Danish infants. The criteria were compared in two age groups: 2-6 and 6-11 months of life.

RESULTS

27% of infants met one or more criteria in at least one of the two age groups. The concurrence among the criteria was generally poor, with most children identified by only one criterion. Positive predictive values of different criteria ranged from 1% to 58%. Most single criteria identified either less than half the cases of significant undernutrition (found in 3%) or included far too many, thus having a low positive predictive value. Children with low weight for height tended to be relatively tall.

CONCLUSIONS

No single measurement on its own seems to be adequate for identifying nutritional growth delay. Further longitudinal population studies are needed to investigate the discriminating power of different criteria in detecting significant undernutrition and subsequent outcomes.

The prevalence of mental health problems in children 1(1/2) years of age - the Copenhagen Child Cohort 2000

BACKGROUND

The Copenhagen Child Cohort, CCC 2000, was established to investigate developmental psychopathology prospectively from birth in a general population.

METHODS

A random sample of 211 children from the CCC 2000 was investigated when the children were 1(1/2) years of age. The prevalence and associates of mental health problems and psychopathology were studied by clinical and standardised strategies, including videotape recordings, parent interviews and the following instruments: The Child Behavior Check List 1(1/2)-5 (CBCL 1(1/2)-5), The Infant Toddler Symptom Check List (ITSCL), Checklist for Autism in Toddlers (CHAT), Bayley Scales of Infant Development II (BSID II), The Parent Child Early Relationship Assessment (PC ERA) and Parent Infant Relationship Global Assessment Scale (PIR-GAS).

RESULTS

Mental health problems according to International Classification of Diseases (ICD-10) and Diagnostic Classification Zero to Three (DC 0-3) diagnoses were found in 16-18% of 1(1/2)-year-old children. Most common were disturbances of emotion, behaviour and eating and the DC 0-3 diagnosis of regulatory disorder. Parent-child relationship disturbances were found in 8%. High psychosocial risk was significantly associated with emotional and behavioural disorders (OR 3.1 95% (1.2-8.1)) and disturbed parent-child relationship (OR 5.0 95% (1.6-16.0)). The strongest association of risk was found between relationship disorders and emotional and behavioural disorders (OR 11.6 95% (3.8-37.5)).

CONCLUSIONS

The prevalence and distribution of psychopathology in 1(1/2)-year-old children seem to correspond to the distributions among older children. Disturbances in parent-child relationship have a key position in the risk mechanisms in early child psychopathology.

Failure to thrive: still a problem of definition

The term 'failure to thrive' (FTT) is widely used to describe inadequate growth in early childhood. However, no consensus exists concerning the specific anthropometrical criteria to define this description. The aim of this study was to make an updated assessment concerning the use of FTT definitions and describe possible trends regarding the use of specific criteria. A cross-sectional review was done covering English-language articles published from January 2003 until June 2004, and recent textbooks of general pediatrics. Most of the reviewed literature broadly defined FTT as inadequate growth and total agreement existed to define FTT based solely on anthropometrical parameters. Large differences, however, were seen regarding which growth parameters to use and whether to use attained values or velocities. Weight was the most predominant choice, but many included more than one anthropometrical parameter. Failure to thrive in children is currently described solely based on anthropometrical indicators, with weight gain as the predominant choice of indicator and cut off around the 5th percentile. Discussion is needed as to whether the term 'failure to thrive' is still a useful common term for pediatric undernutrition of different types.

The growth pattern of 0-1-year-old Danish children, when screened by public health nurses--the Copenhagen County Child Cohort 2000

BACKGROUND

Using inadequate growth references when screening child health could lead to false conclusions concerning individual growth. We were concerned that this might apply to the official Danish growth reference.

AIM

The study aimed to describe the current growth pattern of 0-1-year-old children in Denmark and compare it with national and international references, especially concerning differences that might cause misclassification regarding growth.

SUBJECTS AND METHODS

The study population comprised the Copenhagen County Child Cohort 2000 (CCCC2000) birth cohort, which consisted of 6090 children born during the year 2000. Weight and length measurements were obtained from the National Birth Registry and from standardized records of public health nurses. Anthropometric measurements were available from 99% of the birth cohort. Growth curves were constructed using Cole's LMS method. The curves were compared with Danish and international references, including the NCHS, the CDC and the Euro Growth references.

RESULTS

The CCCC2000 curves differed from all the chosen references. The CCCC2000 children were heavier and longer and with a substantially higher weight-for-age gain between 1 and 6 months. Shape-wise, the CCCC2000 weight curves resemble the new Euro Growth reference.

CONCLUSIONS

The degree of differences concerning weight curves is large enough to cause misclassification and there seems to be a need for updated growth curves concerning infancy.