by Karolinska Institutet

Standardized incidence rate for a) any psychiatric disorder, b) depressive disorders, c) anxiety disorders, d) stress-related disorders, e) eating disorders, f) attention deficit hyperactivity disorder, g) alcohol use disorders, h) autism spectrum disorder, i) drug use disorders, j) bipolar disorder, and k) schizophrenia. Credit: The Lancet Regional Health - Europe (2024). DOI: 10.1016/j.lanepe.2024.101105

A new study by researchers at the Institute for Environmental Medicine (IMM), Karolinska Institutet shows that there are pronounced sex differences in the incidence rates of psychiatric disorders over the lifespan, which vary depending on age, type of psychiatric disorder, calendar period, and socioeconomic status. The paper is published in The Lancet Regional Health - Europe journal.

Psychiatric disorders are among the most pressing global public health concerns. It has been shown that males have a higher risk of neurodevelopmental disorders, while females are more prone to depression and anxiety disorders.

However, most of the evidence was based on prevalence studies, without differentiating new-onset (incident) cases from prevalent and recurrent cases, which may not inform optimal time windows for screening and interventions to reduce sex differences. There is a research gap on sex differences in the incidence of psychiatric disorders over the lifespan.

By using the nationwide Swedish register data and adopting a life-course approach, the researchers at IMM and collaborators from MEB, Uppsala University, Oslo University Hospital, and University of Iceland, have been able to depict a comprehensive atlas of sex differences in the incidence rates of clinically diagnosed psychiatric disorders over the lifespan, with an emphasis on analyzing sex differences by various types of psychiatric disorders, socioeconomic status and calendar period.

Their findings that sex differences in psychiatric disorders exist almost across the whole lifespan supports the need of gendered mental health prevention strategies. The variation in these differences by age and socioeconomic status suggests that current knowledge can be enhanced by integrating data on age and socioeconomic status.

This study also provides evidence for screening and intervention strategies that focus on specific age groups and socially disadvantaged populations, where pronounced sex disparity in psychiatric disorders were observed.

More information: Yihui Yang et al, Sex differences in clinically diagnosed psychiatric disorders over the lifespan: a nationwide register-based study in Sweden, The Lancet Regional Health - Europe (2024). DOI: 10.1016/j.lanepe.2024.101105

Provided by Karolinska Institutet