Incident psychiatric comorbidity following stress disorder diagnoses in Danish school-aged children: prospective population-based study.

BACKGROUND

Prospective population-based studies of psychiatric comorbidity following trauma and severe stress exposure in children are limited.

AIMS: To examine incident psychiatric comorbidity following stress disorder diagnoses in Danish school-aged children using Danish national healthcare system registries.

METHOD: Children (6-15 years of age) with a severe stress or adjustment disorder (ICD-10) between 1995 and 2011 (n = 11 292) were followed prospectively for an average of 5.8 years. Incident depressive, anxiety and behavioural disorder diagnoses were examined relative to an age- and gender-matched comparison cohort (n = 56 460) using Cox proportional hazards regression models. Effect modification by gender was examined through stratified analyses.

RESULTS

All severe stress and adjustment disorder diagnoses were associated with increased rates for all incident outcome disorders relative to the comparison cohort. For instance, adjustment disorders were associated with higher rates of incident depressive (rate ratio RR = 6.8; 95% CI 6.0-7.7), anxiety (RR = 5.3; 95% CI 4.5-6.4), and behavioural disorders (RR = 7.9; 95% CI 6.6-9.3). Similarly, PTSD was also associated with higher rates of depressive (RR = 7.4; 95% CI 4.2-13), anxiety (RR = 7.1; 95% CI 3.5-14) and behavioural disorder (RR = 4.9; 95% CI 2.3-11) diagnoses. There was no evidence of gender-related differences.

CONCLUSIONS

Stress disorders varying in symptom constellation and severity are associated with a range of incident psychiatric disorders in children. Transdiagnostic assessments within a longitudinal framework are needed to characterise the course of post-trauma or severe stressor psychopathology.