Cannabis Use in a Cohort of Healthcare-Seeking United States Military Veterans With Persisting Symptoms After Mild Traumatic Brain Injury: Preliminary Observations
Authors: Utter Brandon , Anderson C Alan , Filley Christopher M , Kelly James P , Johnston-Brooks Catharine , Arciniegas David B 
Published: January 2022

ABSTRACT

Introduction
Cannabis products, including cannabidiol (CBD) and tetrahydrocannabinol (THC), are increasingly easy to procure and use across the United States. The 2018 National Survey on Drug Use and Health (NSDUH) reported a past-month cannabis use rate of 8.6% among adults 26 years of age or older in the U.S. general population. Cannabis use is commonly reported by U.S. Military Veterans with histories of mild traumatic brain injury (mTBI) receiving services at the Marcus Institute for Brain Health (MIBH), a specialty interdisciplinary clinic serving this population. The aims of this study are to describe the frequency and characteristics of cannabis product use among Veterans evaluated at MIBH and to compare the rate of cannabis use in this group to that in the general and Veteran populations reported in the 2018 NSDUH.

Materials and Methods
Study data were collected as part of MIBH clinical assessments between January 2018 and December 2019, which included the evaluation of the current use of cannabis products. Affirmative cannabis use responses were clarified with inquiries about the frequency of use, method of administration, product ingredients (i.e., THC and/or CBD), and reason(s) for use.

Results
Among 163 MIBH patients (92.6% male), 72 (44.2%) endorsed cannabis product use during the month preceding the clinical assessment. Cannabis users were significantly younger than nonusers. The frequency of past-month cannabis use was significantly greater than that reported in the comparably aged NSDUH survey general and Veteran populations (44.2% vs. 8.6% and 44.2% vs. 7.7%, respectively, both P &lt; .00001). Among the 72 MIBH patients reporting cannabis use, 62 (86.1%) reported THC or combination product use, and 10 (13.9%) reported CBD product use. Concurrent medication use, including psychotropic medications use, did not differ significantly between cannabis users and nonusers.

Conclusions
Self-reported cannabis use is significantly higher in the MIBH population than in similarly aged individuals in the general population and significantly more frequent among younger than older members of this cohort. Self-reported reasons for cannabis use in this cohort included mTBI-associated neuropsychiatric symptoms, sleep disturbances, and pain for which standard treatments (both pharmacologic and nonpharmacologic) provided insufficient relief and/or produced treatment-limiting adverse events. However, cannabis use did not provide sufficient improvement in those symptoms to obviate the need for further evaluation and treatment of those problems at MIBH or to replace, in part or in whole, standard medications and other treatments for those problems. Further study of cannabis use, including standardized individual cannabinoid (i.e., THC and CBD) and whole-plant cannabis preparations, in this and similar cohorts is needed to more fully understand the drivers, benefits, risks, and safety of cannabis use in this and in similar Veteran populations, as well as the potential pharmacological and/or nonpharmacological therapeutic alternatives to cannabis use.