Published online May 19, 2020. doi: 10.5498/wjp.v10.i5.101
Peer-review started: December 26, 2019
First decision: February 29, 2020
Revised: March 13, 2020
Accepted: March 30, 2020
Article in press: March 30, 2020
Published online: May 19, 2020
Processing time: 139 Days and 21 Hours
Age and sex are crucial aspects in neurodevelopment and are partly interrelated, presenting as important factors in mental disorders related to neurodevelopment. One example of these disorders are psychotic disorders whose age-at-onset and type (affective vs non-affective) are influenced by sex. Furthermore, in community samples, clinical high risk (CHR) symptoms and criteria that are currently used for an early detection of psychosis, i.e., attenuated and transient psychotic as well as cognitive and perceptual basic symptoms, were reported to be more frequent and less clinically relevant in children and adolescents in whom CHR criteria are also related to lower rates of conversion to psychosis.
From the differences in these age thresholds, i.e., around age 16 for attenuated psychotic symptoms, and around age 18 and 23 for perceptual and cognitive basic symptoms, it was speculated that sex differences in brain and cognitive maturation might lead to lower age thresholds in the clinical significance of BS and possibly APS in females compared to males. Yet, studies on the interaction of age and sex on CHR symptoms and criteria are lacking.
The main objective was to examine the association of age and sex on the presentation and clinical relevance of clinical high-risk criteria and their constituting symptoms in a large community study of 8- to 40-year-olds.
We investigated the effect of both age and sex on the prevalence of CHR criteria and symptoms and on their association with psychosocial impairment and mental disorder in a community sample of n = 2916 8- to 40-year-olds. The sample was composed of community participants in two studies: The “Bern Epidemiology At-Risk” (BEAR) study and the “Binational Evaluation of At-Risk Symptoms in Children and Adolescents” (BEARS-Kid) study. Both studies used a stratified sampling method to obtain a representative sample of 7370 people aged 16–40 years in the BEAR study (response rate: 63.4%) and of 980 minors aged 8-17 years in the BEARS-Kid study (response rate: 32.6%) from citizens of the Swiss Canton of Bern.
Five hundred forty-two (18.6%) participants reported any CHR symptom; of these, 261 (9.0%) participants reported any one of the 11 criteria relevant cognitive and perceptual basic symptoms, and 381 (13.1%) any one of the five attenuated or transient psychotic symptoms. Fewer participants met any one of the four symptomatic CHR criteria (n = 82, 2.8%). Both age and sex were significantly associated with CHR symptoms and criteria, mostly by younger age and female sex. Though slightly differing between symptom groups, age thresholds were detected around the turn from adolescence to adulthood, i.e., around age 18; they were highest for cognitive basic symptoms and CHR criteria, i.e., around age 23. With the exception of the infrequent attenuated psychotic symptom “speech disorganization”, the interaction of age with CHR symptoms and criteria predicted functional impairment; whereas, independent of each other, sex and CHR symptoms mostly predicted mental disorders. Only once, in case of functional impairment, an interaction of both age and sex with CHR symptoms – perceptual basic symptoms – became significant.
Next to confirming the important role of age and sex in the prevalence and clinical relevance of CHR symptoms and criteria, their differential relations to CHR symptoms reveal important insight in possible causal pathways.
In psychosis research, future efforts at unravelling causal pathways of psychosis, at biomarker discovery and at early therapeutic intervention should consider effects of both sex and age.