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IIR 21-200 – HSR Study

IIR 21-200
Gaps in Identification, Referral and Treatment of Cannabis Use in VA Primary Care
Salomeh Keyhani, MD MPH
San Francisco VA Medical Center, San Francisco, CA
San Francisco, CA
Carolyn Gibson PhD MPH
San Francisco VA Medical Center, San Francisco, CA
San Francisco, CA
Funding Period: June 2023 - May 2028


Background: Cannabis use and cannabis use disorder (CUD) are increasing in the US population, and adults aged 50 and older are among the fastest growing groups of cannabis users. While cannabis use is increasing, it is often perceived as harmless and marketed to patients as helpful for several conditions despite a lack of evidence. There is no data on past month cannabis use, daily cannabis use, and CUD among Veterans using primary care, but there is evidence that cannabis use is common in specific Veteran subgroups (11% to 25%) and that CUD identified using administrative data is increasing. Significance: There are reasons to be concerned about the potential under-identification of cannabis use among Veterans. Smoking cannabis is the most common form of cannabis use among Veterans, and there is evidence that cannabis use is associated with respiratory symptoms and cancer. Comorbid mental health conditions are prevalent among Veterans, and these conditions are commonly reported as motivation for regular cannabis use. Cannabis use negatively impacts treatment outcomes of Veterans with anxiety, depression, and post-traumatic stress disorder (PTSD), and use is associated with psychosis and suicidal ideation. Symptoms of cannabis withdrawal can frequently be confused with symptoms of mental health conditions by patients which can perpetuate use. Finally, there are effective behavioral treatments available for CUD and several medications that have shown benefit in treatment of CUD and withdrawal from cannabis in trials. It is important to identify cannabis users to ensure access to effective therapies. Innovation and Impact: This proposal will address important gaps in the priority areas of women’s health, substance use disorders, and mental health. This proposal will lay the foundation for the validation of a simple, frequency-based screening measure for cannabis use that could be feasible in the primary care setting. Specific Aims: We propose to improve our understanding of at-risk populations and determine whether cannabis treatment services in the Veteran population are being underused. We also propose to determine if certain use patterns are associated with adverse mental and physical health outcomes, placing individuals at higher risk. Such individuals (if identified) may also require brief intervention, referral, and/or treatment. Aim 1: To examine the patterns of cannabis use (past month use, daily use, CUD, persistent use), behaviors (e.g., alcohol use) associated with use, and characteristics associated with use among a nationally representative sample of Veterans 50 and older who receive VA primary care. Aim 2a: To determine whether Veterans discuss cannabis use with their providers and whether providers document use and/or intervene upon use or CUD. Aim 2b: To explore provider experiences assessing cannabis use and initiating CUD-related treatment and referrals in the primary care setting. Aim 3: Using the cohort created in Aim 1, we will prospectively examine the association of cannabis use with depression, anxiety, PTSD, insomnia, emergency department use, and all-cause hospitalization. Methodology: We will construct a nationally representative cohort of Veterans 50 and older using VA data, chart review and phone interviews. We will conduct qualitative interviews with primary care providers to understand gaps in care. Next Steps/Implementation: As with alcohol and tobacco, regular cannabis use may be effectively monitored and managed with identification and brief intervention. This proposal will improve our understanding of the prevalence of unidentified cannabis use and gaps in care in the primary care setting, the need for screening, and improve our understanding of the harms associated with use. This proposal will lay the foundation for addressing gaps in care related to cannabis use and CUD among older Veterans.

External Links for this Project

NIH Reporter

Grant Number: I01HX003522-01A2

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None at this time.

DRA: Mental, Cognitive and Behavioral Disorders, Substance Use Disorders
DRE: Prevention, TRL - Applied/Translational
Keywords: Substance Use and Abuse
MeSH Terms: None at this time.

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