Cannabis use in first-treatment bipolar I disorder: relations to clinical characteristics
Version of Record online: 17 APR 2014
© 2014 Wiley Publishing Asia Pty Ltd
Early Intervention in Psychiatry
Volume 10, Issue 1, pages 36–44, February 2016
How to Cite
Kvitland, L. R., Melle, I., Aminoff, S. R., Lagerberg, T. V., Andreassen, O. A. and Ringen, P. A. (2016), Cannabis use in first-treatment bipolar I disorder: relations to clinical characteristics. Early Intervention in Psychiatry, 10: 36–44. doi: 10.1111/eip.12138
- Issue online: 10 JAN 2016
- Version of Record online: 17 APR 2014
- Manuscript Accepted: 28 FEB 2014
- Manuscript Received: 5 NOV 2013
- age at onset;
- bipolar I;
- first treatment
The aim of this study was to investigate the associations between recent cannabis use, current symptomatology and age at onset of first manic, depressive and psychotic episodes in a large sample with first-treatment bipolar I disorder (BD I).
One hundred one patients with first-treatment Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) bipolar I disorder were included as part of the Thematically Organized Psychosis study. The Structural Clinical Interview for DSM-IV was used for DSM-IV diagnosis and identification of episodes of illness. Earlier suicide attempts were recorded. Manic, depressive and psychotic symptoms were rated using the Young Mania Rating Scale, Inventory of Depressive Symptoms and Positive and Negative Syndrome Scale correspondingly. Cannabis use within the six last months was recorded.
After controlling for confounders, recent cannabis use was significantly associated with lower age at onset of first manic and psychotic episode, but not with onset of first depressive episode (both P < 0.05). Recent use was also associated with more lifetime suicide attempts (P < 0.01). No group differences were found on symptom levels.
The present study confirms earlier findings of an association between cannabis use and a lower age at onset. Recent cannabis use was also associated with more lifetime suicide attempts. The current findings suggest that recent cannabis use is associated with a more severe course of illness in the early phase of BD I.