An exploration of research into substance misuse and psychiatric disorder in the UK: what can we learn from history?

BACKGROUND AND AIM

This review explores UK-based research developments in substance misuse and mental illness over the last 25 years. The main body of work comprises policy-orientated projects funded by the Department of Health from the late 1990s. Early research tended to focus on alcohol, especially alcoholic hallucinosis: the relationship of the latter with schizophrenia-like illness was examined, with the finding that very few cases did develop into schizophrenia.

METHOD AND IMPLICATIONS

Parallels are drawn with the current debate around the link between cannabis and psychosis, urging caution in too rapid an assertion that cannabis is necessarily 'causal'. The clinical and policy implications of the misinterpretation of evidence are discussed. A proposal is put forward that the genesis of psychotic illness in alcohol misuse be revisited using more sophisticated research methodologies. Given the changing landscape of substance use in the UK, particularly the fashion of polysubstance use and the recognition that this is associated with psychotic illness, other drugs that are associated with psychotic illness should be similarly investigated to determine whether there is a common mechanism that might throw light on understanding the relationship between substance use and psychotic illness or schizophrenia.