Study register · detailProspektive Kohortenstudie · Adolescence & Development · 2012
Prospective study of cannabis use in adolescents at clinical high risk for psychosis: impact on conversion to psychosis and functional outcome.
Auther et al.·Psychological MedicineImpact 4.3
No benefit demonstratedGRADEModerate99 citations
Samplen = 160 Pat.
Durationan average of 2,97 years
ControlClinical high-risk subjects without…
EndpointConversion to psychosis
Blindingn.a.
DesignProspektive Kohortenstudie
”Key finding
Lifetime cannabis use did not increase the rate of psychosis conversion in clinical high-risk subjects and was associated with better social functioning.
Summary
CHR adolescents (age 12–22 years, n=101 CHR+, n=59 HC), follow-up 2,97 years; low to moderate lifetime cannabis use not a significant predictor of psychosis conversion (logistic regression, n=15 converters); no negative effect on social or role functioning — no increased risk with low-to-moderate use.
P
PopulationAdolescents and young adults (12–22 years) at clinical high risk for psychosis (attenuated positive symptoms, n=101) as well as healthy controls (n=59)
I
InterventionCannabis use (lifetime, including abuse) as exposure
C
ControlClinical high-risk subjects without cannabis use (n=61) or healthy controls (n=59)
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OutcomeNo significant association between lifetime cannabis use/abuse and conversion to psychosis (n=15 converters); cannabis users showed higher social functioning (GF:Social, p<0.001) compared to non-users
Confidence in the evidence
Very lowLowModerateHigh
Moderate
The third of four GRADE levels, the effect estimate is probably reliable.
<h4>Background</h4>Clinical and epidemiological studies suggest an association between cannabis use and psychosis but this relationship remains controversial.<h4>Method</h4>Clinical high-risk (CHR) subjects (age 12-22 years) with attenuated positive symptoms of psychosis (CHR+, n=101) were compared to healthy controls (HC, n=59) on rates of substance use, including cannabis. CHR+ subjects with and without lifetime cannabis use (and abuse) were compared on prodromal symptoms and social/role functioning at baseline. Participants were followed an average of 2.97 years to determine psychosis conversion status and functional outcome.<h4>Results</h4>At baseline, CHR+ subjects had significantly higher rates of lifetime cannabis use than HC. CHR+ lifetime cannabis users (n=35) were older (p=0.015, trend), more likely to be Caucasian (p=0.002), less socially anhedonic (p<0.001) and had higher Global Functioning: Social (GF:Social) scores (p<0.001) than non-users (n=61). CHR+ cannabis users continued to have higher social functioning than non-users at follow-up (p<0.001) but showed no differences in role functioning. A small sample of CHR+ cannabis abusers (n=10) showed similar results in that abusers were older (p=0.008), less socially anhedonic (p=0.017, trend) and had higher baseline GF:Social scores (p=0.006) than non-abusers. Logistic regression analyses revealed that conversion to psychosis in CHR+ subjects (n=15) was not related to lifetime cannabis use or abuse.<h4>Conclusions</h4>The current data do not indicate that low to moderate lifetime cannabis use is a major contributor to psychosis or poor social and role functioning in clinical high-risk youth with attenuated positive symptoms of psychosis.