Personality disorders and long-term sick leave: a population-based study of young adult Norwegian twins

Psychiatric disorders diagnosed in adolescence and subsequent long-term exclusion from education, employment or training: longitudinal national birth cohort study

BACKGROUND

Long-term 'not in education, employment or training' (NEET) status is an important indicator of youth marginalisation.

AIMS

To carry out a comprehensive overview of the associations between different psychiatric illnesses and long-term NEET status.

METHOD

We used the register-based 1987 Finnish Birth Cohort study, which includes all live births in Finland during that year. The analyses comprised 55 273 individuals after exclusions for intellectual disability, death or emigration. We predicted that psychiatric disorders, diagnosed by specialist services between 1998 and 2007 when the cohort were 10-20 years of age, would be associated with subsequent long-term NEET (defined as NEET for at least 5 years between 2008 and 2015, when they were 20-28 years of age).

RESULTS

In total, 1438 individuals (2.6%) were long-term NEET during follow-up and the associations between long-term NEET and the 11 diagnostic categories we studied were statistically significant (P < 0.001). In multivariate models we included sociodemographic characteristics and upper secondary education as covariates, and the highest effect sizes, measured by odds ratios (OR) with 95% confidence intervals (CI), were found for psychosis (OR = 12.0, 95% CI 9.5-15.2) and autism spectrum disorder (OR = 17.3, 95% CI 11.5-26.0). If individuals had not successfully completed this education, 70.6% of those with autism spectrum disorder and 48.4% of those with psychosis were later long-term NEET.

CONCLUSIONS

Adolescents who receive treatment for psychiatric disorders, particularly autism spectrum disorder or psychosis, need support to access education and employment. This could help to prevent marginalisation in early adulthood.

Internalizing and externalizing problems in childhood and adolescence as predictors of work incapacity in young adulthood

BACKGROUND

There is limited information regarding the association between youth mental health problems and work incapacity in adulthood. We investigated whether internalizing (depressive, anxious, somatic complaints) and externalizing (aggressive, rule-breaking) behavior problems in childhood and adolescence were associated with sickness absence (SA) and disability pension (DP) in young adulthood.

METHODS

Data were used from the population-based and prospective Twin Study of Child and Adolescent Development (TCHAD) which includes all Swedish twins born in 1985-1986 (N = 2570). Internalizing and externalizing behavior problems were assessed with the Child Behavior Checklist at ages of 8-9, 13-14, 16-17, and 19-20 years. Individuals participating in TCHAD were followed regarding SA and DP during 2001-2013 using nationwide registers. Cox regression models were applied to assess hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

Each one-unit increase of rule-breaking behavior implied a significant higher risk for SA in early adulthood, despite of age at assessment, with the highest HR of 1.12 (95% CI 1.05-1.19) at age of 8-9 years. Higher levels of anxious and depressive symptoms in childhood and adolescence were associated with DP in early adulthood despite age at assessment, with the highest risk at age 19-20 years [HR 1.31 (95% CI 1.12-1.53)]. The associations attenuated slightly when familial factors were taken into account.

CONCLUSIONS

Internalizing and externalizing behavior problems identified at an early age (8-9 years) increased risk for SA and DP in young adulthood. These findings indicate that early prevention and intervention efforts to reduce behavior problems may promote a successful start in working life.

High Job Demands, Job Strain, and Iso-Strain are Risk Factors for Sick Leave due to Mental Disorders: A Prospective Swedish Twin Study With a 5-Year Follow-Up

OBJECTIVE

To investigate whether psychosocial work environment and health behaviors are risk factors for sick leave due to mental disorders, and whether familial confounding (genetics and shared environment) explains the associations.

METHODS

Respondents (n = 11,729), given to complete a questionnaire in 2004 to 2006, were followed up approximately 5 years for sick leave spells due to mental disorders, using national registry data. Data were analyzed using logistic regression, and conditional logistic regression for twin pairs discordant for sick leave (cotwin control).

RESULTS

High job demands, job strain, and iso-strain were independent risk factors for sick leave due to mental disorders. Familial factors seem to be of importance in the associations between job support, smoking, a combination of unhealthy behaviors and sick leave.

CONCLUSIONS

Improving the psychosocial work environment may be effective in preventing sick leave due to mental disorders.

Genetic and Environmental Influences on Disability Pension Due To Mental Diagnoses: Limited Importance of Major Depression, Generalized Anxiety, and Chronic Fatigue

BACKGROUND

Previous research indicates that liability to disability pension (DP) due to mental diagnoses is moderately influenced by genetic factors. This study investigates whether genetic contributions to the liability to DP due to mood and neurotic diagnoses overlap with the genetic influences on major depression (MD), generalized anxiety disorder (GAD), or chronic fatigue (CF).

METHOD

A prospective cohort study including 9,985 female twins born in Sweden 1933-1958. The presence of MD, GAD, and CF was assessed by computer-assisted telephone interviews conducted in 1998-2002. Data on DP due to mood and neurotic diagnoses were obtained from nationwide registers for the years 1998-2010. Common genetic and environmental influences on the phenotypes were estimated by applying structural equation modeling.

RESULTS

The prevalence of MD/GAD was 30%, CF 8%, and DP due to mood and neurotic diagnoses 3% in 2010. Genetic effects on MD/GAD explained 31% of the total genetic variation in DP, whereas genetic contributions in common with CF were small and not significant. The majority of the total non-shared environmental variance in DP (85%) was explained by the factors that were unique to DP.

CONCLUSIONS

Large proportions of genetic and non-shared environmental influences in DP due to mood and neurotic diagnoses were not explained by the contributions from MD/GAD or CF. The results suggest that the process leading to DP is complex and influenced by factors other than those related to the disorder underlying DP.

Traffic-related air pollution and brain development

Automotive traffic-related air pollution (TRP) imposes an increasing health burden with global urbanization. Gestational and early child exposure to urban TRP is associated with higher risk of autism spectrum disorders and schizophrenia, as well as low birth weight. While cardio-respiratory effects from exposure are well documented, cognitive effects are only recently becoming widely recognized. This review discusses effects of TRP on brain and cognition in human and animal studies. The mechanisms underlying these epidemiological associations are studied with rodent models of pre- and neonatal exposure to TRP, which show persisting inflammatory changes and altered adult behaviors and cognition. Some behavioral and inflammatory changes show male bias. Rodent models may identify dietary and other interventions for neuroprotection to TRP.

The covariation between burnout and sick leave due to mental disorders is explained by a shared genetic liability: a prospective swedish twin study with a five-year follow-up

BACKGROUND

This study aims to assess whether the associations between burnout and sick leave due to stress-related mental disorders, other mental disorders, and somatic conditions are influenced by familial (genetic and shared environmental) factors.

METHODS

In this prospective cohort study, 23,611 Swedish twins born between 1959 and 1985, who answered a web-based questionnaire, including the Pines Burnout Measure 2004-2006, were included. Registry data on sick leave spells from the response date until December 31, 2010 were obtained from the Swedish Social Insurance Agency. Logistic regression analysis was performed to assess odds ratios with 95% confidence intervals for the association between burnout and sick leave for the whole sample, while conditional logistic regression of the same-sex discordant twin pairs was used to estimate the association between burnout and sick leave, adjusting for familial confounding. The Bivariate Cholesky models were used to assess whether the covariation between burnout and sick leave was explained by common genetic and/or shared environmental factors.

RESULTS

Burnout was a risk factor for sick leave due to stress-related and other mental disorders, and these associations were explained by familial factors. The phenotypic correlation between burnout and sick leave due to somatic conditions was 0.07 and the association was not influenced by familial factors. The phenotypic correlations between burnout and sick leave due to stress-related (0.26) and other mental disorders (0.30) were completely explained by common genetic factors.

CONCLUSIONS

The association between burnout and sick leave due to stress-related and other mental disorders seems to be a reflection of a shared genetic liability.