To what extent psychotic symptoms in first-episode psychosis (FEP) with a history of childhood interpersonal trauma (CIT) are less responsive to antipsychotic medication is not known. In this longitudinal study, we compare symptom trajectories and remission over the first 2 years of treatment in FEP with and without CIT and examine if differences are linked to the use of antipsychotics.

FEP (N = 191) were recruited from in- and outpatient services 1997–2000, and assessed at baseline, 3 months, 1 and 2 years. Inclusion criteria were 15–65 years, actively psychotic with a DSM-IV diagnosis of psychotic disorder and no previous adequate treatment for psychosis. Antipsychotic medication is reported as defined daily dosage (DDD). CIT (<18) was assessed with the Brief Betrayal Trauma Survey, and symptomatic remission based on scores from the Positive and Negative Syndrome Scale.

CIT (n = 63, 33%) was not associated with symptomatic remission at 2 years follow-up (71% in remission, 14% in relapse), or time to first remission (CIT 12/ no-CIT 9 weeks, p = 0.51). Those with CIT had significantly more severe positive, depressive, and excited symptoms. FEP with physical (N = 39, 20%) or emotional abuse (N = 22, 14, 7%) had higher DDD at 1 year (p < 0.05). Mean DDD did not excerpt a significant between-group effect on symptom trajectories of positive symptoms.

Results indicate that antipsychotic medication is equally beneficial in the achievement of symptomatic remission in FEP after 2 years independent of CIT. Still, FEP patients with CIT had more severe positive, depressive, and excited symptoms throughout.

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).

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.

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.

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.