A nationally representative survey of ICD-11 PTSD among Danish adolescents and young adults aged 15-29.

Posttraumatic stress disorder (PTSD) is recognized as a debilitating psychiatric disorder affecting populations worldwide. This has inspired many countries to estimate the national prevalence rates of PTSD in Europe and beyond. At present, there are no published representative studies that have assessed the occurrence of trauma exposure and PTSD in Denmark using a valid measurement based on ICD-11 criteria. A national sample of the general population of young Danish residents, ranging in age between 15 to 29 years (n = 2,434), was surveyed cross-sectionally from April to October 2022. Data weights were applied to ensure representativity of the sample. Multiple regression was used to study the relationship between trauma exposure, sex, age, and PTSD. Accidents and violence were the most common types of trauma exposure with females being more likely to experience sexual violence. A total of 7.7% endorsed probable PTSD with women reporting higher rates of clinical and subclinical PTSD (12.3% and 12.7%, respectively) than men (3.5% and 7.3%, respectively). Findings from the multiple regression showed that female gender was associated with higher PTSD-severity, although the strongest predictor was trauma-type with other types of traumas, and sexual violence displaying the strongest relationship to PTSD-severity overall. A dose-response relationship between the number of trauma types and PTSD symptomatology was found. This is the first study of PTSD in a nationally representative Danish sample using a valid measure of ICD-11 PTSD. The identified PTSD rates were higher than Danish official estimates in a representative sample of the Danish adolescent and young adult population (7.7% weighted compared to 1%). The study replicated international findings of sex differences in probable PTSD endorsement.