An investigation of the relationship between bipolar disorder and cannabis use

• Main Author: Tyler, Elizabeth
• Other Authors: Barrowclough, Christine ; Calam, Rachel
• Published: University of Manchester 2011
• Subjects: 616.89
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548697

Substance abuse is very common in Bipolar Disorder (BD) and can lead an individual having an increased range of difficulties. Studies have indicated that cannabis is used very frequently, but most research into substance use and BD has focused on either alcohol use or substance use disorders generally. The relationship between BD and cannabis use specifically has received far less attention. This thesis specifically explored the co-occurring relationship between BD and cannabis use. In the first section the author examines and critically evaluates studies that have reported on the relationship between BD and cannabis use. The initial phase included a literature search of the area and the identification of relevant papers. A total of 13 research studies were identified and included in the final review. The studies varied considerably in terms of their research questions, design and methodological quality. The findings from the studies were synthesised in relation to a number of existing hypotheses for why BD and substance use in general co-occur. On the whole, the 13 studies contributed sufficient evidence both for and against the existing hypotheses. The findings suggest that there are a number of factors that contribute towards the high co-occurrence of BD and cannabis use (e.g. the use of cannabis to self-medicate symptoms).The second section was designed to investigate a number of the factors derived from the literature which might explain the high co-occurrence of BD and cannabis use. The Experience Sampling Methodology (ESM) was utilised to provide a close investigation of a number of factors over the course of daily life. Twenty-three participants with BD type I and type II completed diary entries for 6 days using ESM. The procedure allowed a close investigation into the associations between cannabis, mood, BD symptoms and Behavioural Activation System (BAS) sensitivity. Self-reported BAS was also measured to indicate the extent to which this predicted changes in mood, BD symptoms and cannabis use. The findings indicate that cannabis use is associated with a number of psychological effects, although no evidence for the self- medication of mood and BD symptoms was revealed in the daily life of the participants. An association between BAS sensitivity and positive affect and manic symptoms was revealed and this is consistent with the findings in current literature. The final section provides a critical reflection of the research process. This includes a rationale for the development of the literature review and the main research paper. This is followed by a description of the study context and then a reflection on the methodological and ethical issues which were faced. Finally it discusses theoretical, clinical and future implications for research in this area.