Cannabis use prior to first onset psychosis predicts spared neurocognition at 10-year follow-up

Stirling, John; Lewis, Shon; Hopkins, Richard; White, Colin

doi:10.1016/j.schres.2004.10.006

« Previous Next »Schizophrenia Research
Volume 75, Issue 1 , Pages 135-137, 1 June 2005

Cannabis use prior to first onset psychosis predicts spared neurocognition at 10-year follow-up

John Stirling
- Department of Psychology and Speech Pathology, Manchester Metropolitan University, Elizabeth Gaskell Building, Hathersage Road, M13 0JA, UK
- School of Psychiatry and Behavioural Sciences, University of Manchester, Wythenshawe Hospital, M23 9LT, UK
- Corresponding author. Department of Psychology and Speech Pathology, Manchester Metropolitan University, Elizabeth Gaskell Building, Hathersage Road, M13 0JA, UK. Tel.: +44 161 247 2561; fax: +44 161 247 6364.
Shon Lewis
- School of Psychiatry and Behavioural Sciences, University of Manchester, Wythenshawe Hospital, M23 9LT, UK
Richard Hopkins
- School of Psychiatry and Behavioural Sciences, University of Manchester, Wythenshawe Hospital, M23 9LT, UK
Colin White
- School of Psychiatry and Behavioural Sciences, University of Manchester, Wythenshawe Hospital, M23 9LT, UK

Received 23 August 2004; received in revised form 8 October 2004; accepted 21 October 2004.

Abstract

A priori cannabis use was recorded at index admission for 112 participants in the Manchester first-episode psychosis cohort. 69 of the 100 surviving (mainly schizophrenia) patients were followed up 10–12 years later and assessed on a battery of clinical, behavioural and neurocognitive measures. Individuals who had not used cannabis before the first episode of illness were generally indistinguishable from cannabis users at follow-up, except that the latter group evidenced a marked ‘sparing’ of neurocognitive functions. These findings are briefly discussed in relation to other casual factors in psychosis.

Keywords: Cannabis, First onset psychosis, Neurocognition