Family History of Psychosis in Adolescents May Mean Milder Initial Symptoms, Not Worse Ones | Research

The takeaway

Contrary to expectations, adolescents with first-episode psychosis who had a family history of psychosis actually showed milder positive symptoms at onset, and family history rates did not differ between psychotic and non-psychotic mental illness.

Readers interested in how genetics and family history relate to psychosis risk in young people.

Family history of psychosis was linked to lower positive symptom scores at first episode (p = 0.009)

What the researchers found

Researchers compared 45 adolescents with first-episode early-onset psychosis (EOP) to 45 age- and gender-matched adolescents with non-psychotic mental illness. Family history of psychosis did not significantly differ between the two groups.

However, among the psychotic adolescents, those with a positive family history of psychosis had significantly lower positive symptom scores on the PANSS (p = 0.009), meaning fewer hallucinations, delusions, and other positive symptoms at the time of first presentation. Family history was not associated with other clinical features.

Notably, adolescents with non-psychotic mental illness were significantly more likely to have a family history of non-psychotic mental illness (47%) compared to the psychotic group (13%, p = 0.001).

Why it matters

The assumption that family history of psychosis predicts worse outcomes may not hold true at disease onset in adolescents. This finding could influence how clinicians interpret family history when evaluating young people with first psychotic episodes. The inclusion of cannabis screening adds context to understanding substance use patterns in this population.

The numbers in context

45 psychotic adolescents vs. 45 matched controls. Family history of non-psychotic mental illness: 13% in EOP group vs. 47% in controls (p = 0.001). Positive family history of psychosis was associated with lower PANSS positive scores (p = 0.009).

How the study worked

This was a case-control study at psychiatric services in South Africa. Forty-five adolescents with first-episode psychosis were matched with 45 controls who had non-psychotic mental illness. Assessments included the PANSS for symptom severity, the SOS inventory for symptom onset, and the WHO ASSIST screening tool for cannabis use.

What this study cannot tell us

Small sample size (45 per group) limits statistical power. The study was conducted at a single site in South Africa, which may limit generalizability. Cannabis use data was collected but the abstract does not detail specific associations with outcomes. Cross-sectional design captures only the initial presentation, not long-term trajectory.

How to read the evidence

Preliminary evidence from a small, single-site case-control study.

When this study was published

Published in 2017. South African study on adolescent psychosis.

The bigger picture

Understanding the relationship between family history, genetics, and early-onset psychosis is critical for early intervention. This study challenges the simple narrative that family history equals worse outcomes and suggests the genetics of psychosis susceptibility may operate differently in adolescents than in adults.

Questions still open

Why would family history of psychosis be associated with milder initial symptoms? Does this pattern hold over time, or do these patients eventually develop more severe symptoms? What role did cannabis use play in the onset of psychosis in these adolescents?

Common questions

Does this study mean family history of psychosis is protective?

Not necessarily protective, but the study found that having a family history was associated with milder positive symptoms at the time of first psychotic episode. This was the initial presentation only, and long-term outcomes were not tracked.

What role did cannabis play in this study?

Cannabis use was screened for using the WHO ASSIST tool, but the abstract does not detail specific findings about cannabis and psychosis in these adolescents. The study included cannabis assessment as part of a comprehensive clinical evaluation.

Read the original research

The clinical impact of a positive family history of psychosis or mental illness in psychotic and non-psychotic mentally ill adolescents.

Journal of child and adolescent mental health, 29(3), 219-229

View on PubMed ↗Publisher’s paper ↗

Citation

Paruk, Saeeda; Jhazbhay, Khatija; Singh, Keshika; Sartorius, Benn; Burns, Jonathan K. (2017). The clinical impact of a positive family history of psychosis or mental illness in psychotic and non-psychotic mentally ill adolescents.. Journal of child and adolescent mental health, 29(3), 219-229. https://doi.org/10.2989/17280583.2017.1389741