Cannabis use, polysubstance use, and psychosis prodrome among first-degree relatives of patients with schizophrenia

ABSTRACT

Background

Cannabis use and Psychosis are closely associated. Polysubstance use is prevalent among cannabis users. However, previous literature majorly examined the relationship between only cannabis use and schizophrenia disorder. Little is known about the impact of polysubstance use on the onset of prodromal symptoms. There is a scarcity of studies comparing the severity and characteristics of prodromal symptoms between cannabis users and polysubstance users.

Aim

This study investigates the association between polysubstance use and prodromal symptoms. It also compares the severity and characteristics of prodromal symptoms among individuals with different substance use patterns.

Method

246 first-degree relatives of patients with schizophrenia participated in the study, using purposive sampling method. Pattern of substance use and prodromal symptoms were assessed using the WHO ASSIST Scale and PROD-Screen respectively.

Result

Significant association was found between substance use and symptoms of prodrome (r = −0.57, p < .01). Individuals who consumed more than one substance experienced more severe prodromal symptoms. Prodromal symptoms viz. “hallucinatory and delusional symptoms” and affect and thinking difficulties discriminate the study groups effectively.

Conclusion

Cannabis plus other substance use increases the risk of prodrome among first-degree relatives of patients with schizophrenia. Polysubstance use causes more thinking, affective, delusionary, and hallucinatory symptoms of prodrome.

KEYWORDS:

• Cannabis
• first-degree relatives
• psychosis prodrome
• polysubstance use

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Deidentified individual participant data (including data dictionaries) that underlie the results reported in this article (text, tables, figures, the informed consent form, and the statistical analysis plan) will be made available for wider use. The data will be made available upon publication and for life time, to the researchers who provide a methologically sound proposal for use in achieving goals of the approved proposal. All available data can be obtained by contacting the corresponding author. Proposals should be submitted to [email protected].

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.