In youth at clinical high risk for psychosis, persistent negative symptoms were most strongly linked to poor premorbid functioning in late adolescence, while the group without persistent negative symptoms actually had more cannabis use.
Read this if you work in early psychosis intervention or want to understand risk factors for negative symptoms in at-risk youth.
9.4%Proportion of clinical high-risk youth who developed persistent negative symptoms
What the researchers found
Among 709 clinical high-risk youth, 67 (9.4%) had persistent negative symptoms. These individuals were more often male and had significantly worse premorbid adjustment across childhood, early adolescence, and late adolescence. Surprisingly, the group without persistent negative symptoms had more cannabis use and more life events (both desirable and undesirable). There were no differences between groups in trauma, bullying, or resource utilization. Poor premorbid functioning in late adolescence was the most prominent predictor of persistent negative symptoms.
Why it matters
Negative symptoms (social withdrawal, reduced motivation, flat affect) are among the most disabling aspects of psychotic disorders and are resistant to treatment. Identifying who develops them early could allow for targeted early intervention.
The numbers in context
- 709 clinical high-risk participants from NAPLS 2
- 67 (9.4%) had persistent negative symptoms vs 673 without
- More males in the persistent negative symptoms group
- Non-PNS group had more cannabis use
- Poor late-adolescent premorbid functioning was the strongest predictor
How the study worked
Participants from the North American Prodrome Longitudinal Study (NAPLS 2) were divided into persistent negative symptoms vs. non-persistent groups. K-means cluster analysis distinguished premorbid functioning patterns. Group comparisons used t-tests and chi-square analyses.
Who was studied
709 youth at clinical high risk for psychosis from the NAPLS 2 study
What this study cannot tell us
Observational design cannot establish causation. The higher cannabis use in the non-PNS group could reflect greater social engagement rather than a protective effect. The study did not track whether high-risk participants later converted to full psychosis.
How to read the evidence
Large prospective cohort study (NAPLS 2) with validated instruments. Strong methodology for identifying risk factors in a well-characterized population.
When this study was published
Published in 2023. Uses data from a major ongoing longitudinal study of psychosis risk.
The bigger picture
The finding that cannabis use was actually lower in the persistent negative symptoms group challenges simple narratives about cannabis causing psychosis. The relationship between cannabis and psychosis risk may be more nuanced, with social withdrawal itself being a key variable.
Questions still open
- Does the lower cannabis use in the PNS group reflect social isolation rather than a causal relationship?
- Could early intervention targeting social skills in late adolescence prevent persistent negative symptoms?
- Do persistent negative symptoms in high-risk youth predict conversion to schizophrenia?
Read the original research
The impact of early factors on persistent negative symptoms in youth at clinical high risk for psychosis.
Frontiers in psychiatry, 14, 1125168
Citation
Devoe, Daniel J; Lui, Lu; Cannon, Tyrone D; Cadenhead, Kristin Suzanne; Cornblatt, Barbara A; Keshavan, Matcheri; McGlashan, Tom H; Perkins, Diana O; Seidman, Larry J; Stone, William S; Tsuang, Ming T; Woods, Scott W; Walker, Elaine F; Mathalon, Daniel H; Bearden, Carrie E; Addington, Jean. (2023). The impact of early factors on persistent negative symptoms in youth at clinical high risk for psychosis.. Frontiers in psychiatry, 14, 1125168. https://doi.org/10.3389/fpsyt.2023.1125168