Study register · detailProspektive Kohortenstudie · Psychosis Risk · 2012
Prevalence and impact of cannabis use disorders in adolescents with early onset first episode psychosis.
Schimmelmann et al.·European Psychiatry
MixedGRADEVery low97 citations
Samplen = 99 Pat.
Duration18 months
ControlPatients without cannabis use disorder
EndpointPsychosocial functional status
Blindingn.a.
DesignProspektive Kohortenstudie
”Key finding
Only persistent cannabis use, not baseline use alone, is associated with poorer clinical outcomes in adolescent first-episode psychosis.
Summary
Representative cohort (n=99) of adolescents (14–18 years) with early-onset first psychotic episode: prevalence of lifetime cannabis use disorder (CUD) 65,7%, current CUD at admission 53,5%, persistent CUD over the course of treatment 26,3%. Only persistent CUD was associated with significantly poorer 18-month outcomes (medium effect sizes after confounder control), while baseline CUD was primarily associated with more severe baseline symptoms and lower psychosocial functioning (p-values not given numerically, but effect sizes medium).
P
PopulationAdolescents (14–18 years) with early-onset first-episode psychosis (EOP), n=99, Australia
I
InterventionObservation of cannabis-use-disorders (CU) – prevalence, baseline and course characteristics over 18 months
C
ControlPatients without cannabis use disorder (NCU)
O
OutcomePersistent CU (26,3 %) was associated with poorer 18-month outcomes and more treatment discontinuations (medium effect sizes after confounder adjustment); baseline CU alone predicted poorer baseline characteristics but not poorer long-term outcomes
Confidence in the evidence
Very lowLowModerateHigh
Very low
The lowest GRADE level, the effect estimate remains uncertain.
<h4>Background</h4>Previous studies on the impact of cannabis use disorders (CU) on outcome in psychosis were predominantly based on non representative samples, often have not controlled for confounders and rarely focused on adolescent patients. Thus, the aims of the present study were to assess: (i) prevalence of CU; (ii) baseline and pretreatment differences between CU and those without CU (NCU); (iii) the impact of baseline and course of CU on 18-month outcomes in a representative cohort of adolescents with early onset first episode psychosis (EOP).<h4>Methods</h4>The sample comprised 99 adolescents (age 14 to 18) with EOP (onset age 14 to 17), admitted to the Early Psychosis Prevention and Intervention Centre in Australia. Data were collected from medical files using a standardized questionnaire.<h4>Results</h4>Prevalence of lifetime CU was 65.7%, of current CU at baseline 53.5%, and of persistent CU throughout treatment 26.3%. Baseline CU compared to NCU had significantly higher illness-severity, lower psychosocial functioning, less insight, lower premorbid functioning and longer duration of untreated psychosis. Compared to all other groups, only persistent CU was linked to worse outcomes and more service disengagement. Effect sizes were medium controlling for relevant confounders. Medication non-adherence did not explain the association between persistent CU and worse outcome.<h4>Conclusions</h4>Baseline CU was associated with worse baseline characteristics, but only persistent CU was linked with worse outcome. About half of those with baseline CU reduced cannabis during treatment. For these, effectively treating the psychotic disorder may already be beneficial. However, future research is necessary on the reasons for persistent CU in EOP and its treatment.