Cannabis use and first-episode psychosis: relationship with manic and psychotic symptoms, and with age at presentation
James Stone, Helen L. Fisher, Barnaby Major, Brock Chisholm, James Woolley, Jo Lawrence, Nikola Rahaman, John Joyce, Mark Hinton, Sonia Johnson, Allan H. Young
Psychological Medicine May 24, 2013 DOI: 10.1017/s0033291713000883 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Longitudinal Peer reviewed |
|---|---|
| Sample size | 502 |
| Population | Patients with first-episode psychosis from seven London-based Early Intervention in psychosis teams |
| Duration | 1-year follow-up |
| Topics | Cannabis |
| Keywords | Psychosis Mania Schizophrenia object-oriented programming Bipolar disorder Clinical psychology Mood |
| Citations | 69 |
| Key findings | Cannabis use was associated with younger age at presentation, more manic symptoms and conceptual disorganization, and reducing or stopping use led to the greatest symptom improvement at one year. |
Abstract
Background: Cannabis use has been reported to be associated with an earlier onset of symptoms in patients with first-episode psychosis, and a worse outcome in those who continue to take cannabis. In general, studies have concentrated on symptoms of psychosis rather than mania. In this study, using a longitudinal design in a large naturalistic cohort of patients with first-episode psychosis, we investigated the relationship between cannabis use, age of presentation to services, daily functioning, and positive, negative and manic symptoms.
Method: Clinical data on 502 patients with first-episode psychosis were collected using the MiData audit database from seven London-based Early Intervention in psychosis teams. Individuals were assessed at two time points--at entry to the service and after 1 year. On each occasion, the Positive and Negative Syndrome Scale, Young Mania Rating Scale and Global Assessment of Functioning Scale disability subscale were rated. At both time points, the use of cannabis and other drugs of abuse in the 6 months preceding each assessment was recorded.
Results: Level of cannabis use was associated with a younger age at presentation, and manic symptoms and conceptual disorganization, but not with delusions, hallucinations, negative symptoms or daily functioning. Cannabis users who reduced or stopped their use following contact with services had the greatest improvement in symptoms at 1 year compared with continued users and non-users. Continued users remained more symptomatic than non-users at follow-up.
Conclusions: Effective interventions for reducing cannabis use may yield significant health benefits for patients with first-episode psychosis.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cited by 11
- Drug models of schizophrenia. Therapeutic Advances in Psychopharmacology February 1, 2015
- Psicosis inducida por cannabis: características clínicas y su diferenciación con la esquizofrenia con y sin consumo de cannabis asociado Adicciones July 14, 2020
- Clinical Investigation on the Impact of Cannabis Abuse on Thyroid Hormones and Associated Psychiatric Manifestations in the Male Population Frontiers in Psychiatry December 3, 2021
- Association between formal thought disorder and cannabis use: a systematic review and meta-analysis Schizophrenia September 29, 2022
- Clinical and Sociodemographic Characteristics of Young People With Early Psychosis: Comparing Cannabis Users and Non‐Users in a Specialized Early Intervention Setting Early Intervention in Psychiatry August 1, 2026
and 6 more in the library
Cites 5
- Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study BMJ March 1, 2011
- Effects of cannabis use on outcomes of psychotic disorders: systematic review The British Journal of Psychiatry October 31, 2008
- Does Change in Cannabis Use in Established Psychosis Affect Clinical Outcome? Schizophrenia Bulletin October 29, 2011
- Cannabis and First-Episode Psychosis: Different Long-term Outcomes Depending on Continued or Discontinued Use Schizophrenia Bulletin November 13, 2009
- Cannabis use and outcome of recent onset psychosis European Psychiatry June 1, 2005