Traits and Biomarkers for Addiction Risk in Schizophrenia
The most common addictions in schizophrenia include tobacco, cannabis, alcohol, stimulants/recreational drugs, and gambling. This review discusses the multifactorial risk factors for addictions in people with schizophrenia.
Several hypotheses have been proposed to explain addiction comorbidity in schizophrenia, and potential biomarkers conferring addiction risk in patients have been identified (e.g., catechol-O-methyltransferase (COMT), brain-derived neurotrophic factor (BDNF), v-akt murine thymoma viral oncogene homolog 1 (AKT1), cortical inhibition, working memory). Neurotransmitter systems including dopaminergic, glutamatergic, and GABAergic pathways are associated with the pathophysiology of both schizophrenia and addictions.
Developing effective treatments for schizophrenia and comorbid addictions is warranted and should involve further studies of neurobiological underpinnings of addiction risk in schizophrenia.
KeywordsSchizophrenia Addiction risk Substance use disorders Tobacco/nicotine Cannabis Alcohol Stimulants Problem gambling
This manuscript was support by an Institute of Medical Sciences Graduate Fellowship from the University of Toronto (to Ms. Kozak) and CIHR Operating Grant MOP#115145 (to Dr. George).
Compliance with Ethical Standards
Conflict of Interest
Karolina Kozak, Dr. Mera S. Barr, and Dr. Tony P. George declare that they have no conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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