Do cannabis use disorders increase medication non-compliance in schizophrenia?: United States Nationwide inpatient cross-sectional study.

Journal Article (Journal Article)


This study aims to find the prevalence of medication non-compliance among schizophrenia inpatients and to compare the relative risks of medication non-compliance with cannabis use disorders (CUDs) versus without CUDs. In addition, this study also examines the odds of medication non-compliance in schizophrenia inpatients with CUDs.


This is a retrospective cross-sectional analysis of the nationwide inpatient sample. This sample includes 1,030,949 inpatients (age 18 to 65 years) from 2010 to 2014 with primary ICD-9 diagnoses of schizophrenia and other psychotic disorders, that were further sub grouped based on medication non-compliance. CUDs were recognized using the ICD-9 codes.


The prevalence of medication non-compliance was 26% among schizophrenia inpatients. Multivariable analysis revealed that CUD comorbidity was a significant risk factor for medication non-compliance among schizophrenia patients when unadjusted (OR 1.49, 95%CI 1.469-1.503), and association remained significant even after adjusting for covariates (adjusted OR 1.38, 95%CI 1.268-1.489). Comorbid CUD was seen in young adults (18-35 years, 62.4%), males (80.5%), African Americans (54.1%) and low-income families below 25th percentile (48.6%) with personality disorders (10.5%).


Medication compliance is a challenge among schizophrenia patients, which has a significant adverse impact on the course of illness. CUD Comorbidity increases the risk of medication non-compliance significantly among schizophrenia patients. In addition to case management, an integrated treatment model to address both substance use disorders and psychosis will translate into better long-term outcomes in schizophrenia patients.

Full Text

Duke Authors

Cited Authors

  • Patel, RS; Sreeram, V; Vadukapuram, R; Baweja, R

Published Date

  • October 2020

Published In

Volume / Issue

  • 224 /

Start / End Page

  • 40 - 44

PubMed ID

  • 33183946

Electronic International Standard Serial Number (EISSN)

  • 1573-2509

International Standard Serial Number (ISSN)

  • 0920-9964

Digital Object Identifier (DOI)

  • 10.1016/j.schres.2020.11.002


  • eng