Medical Marijuana Use and Driving Performance: A Test of Psychomotor Function in Adults 50 and Older

The proposed study is a prospective repeated measures experimental study designed to test medical marijuana use as the exposure variable in adults age 50 and older and driving errors in response time, attention, and executive functions as the primary outcome. Secondary outcomes include: unwanted effects. Participants will complete 3 assessments over a 3-month time period. The 3 assessment time points are: baseline (T1) prior to starting medical marijuana, 1 month post-medical marijuana initiation (T2), and 3 months post-medical marijuana initiation (T3). Electronic Medical Review (EMR) will be conducted at baseline, 1 and 3 months. In addition, potentially confounding disease, treatment, and sociodemographic characteristics will be examined. Data will be collected in a manner that is consistent with transparent reporting as mandated by CONSORT guidelines. Finite mixture modeling and generalized linear modeling accounting for individual and group level outcomes will be used to test the study hypotheses.

Participants will be N=60 adults ages 50 and older who have newly registered with the state of Florida to obtain medical marijuana (n=30) or age, race, sex matched non-marijuana user controls (n=30).

Intervention Group Recruitment. Participants will be recruited from Medical Marijuana Treatment Clinics of Florida's (MMTC) Gainesville location. Recruitment for this study begins pre-medical marijuana exposure. To obtain medical marijuana in the state of Florida there are four steps:

• Step 1: Determine Eligibility: Eligibility for medical marijuana use must be determined by a qualified physician. A patient must first seek treatment from a qualified physician. MMTC has qualified physicians who determine patient eligibility.
• Step 2: Medical Marijuana Registration: Once the MMTC physician determines the patient is eligible for medical marijuana, the physician then inputs the patient's information and the medical marijuana order information into the Medical Marijuana Use Registry. MMTC physicians complete this process during the eligibility appointment. Recruitment for the current project begins at step 2 which is prior to any exposure to medical marijuana. Participants will undergo a brief screen during their visit with the MMTC physician to determine if they meet eligibility criteria (See Eligibility Criteria in Human Study Record 1 per new National Institute of Health (NIH) guidelines). Eligibility screening procedures will be institution review board (IRB)-approved and will not collect any identifying information. Self-report questionnaires will be use to discern eligibility. Eligibility will be confirmed using medical records at enrollment. If MMTC patients meet eligibility criteria, they will be given the opportunity to meet with the study research assistant (RA) to learn more about the project. Participants will be provided a detailed description of the study, and the research assistant will obtain permission to follow up with the patient (by phone or text) in order to track their progress on obtaining their registry identification card.
• Step 3: Medical Marijuana Use Registry Identification Card: Once a physician has input the patient's information into the Medical Marijuana Use Registry (i.e. step 2), the patient is able to apply for a medical marijuana card. This process takes approximately 10-14 days. Participants will be instructed to schedule their baseline study visit prior to obtaining their first dose of medical marijuana. At the baseline appointment the study staff will obtain informed consent and complete the biobehavioral assessment measures, and participants will complete their first drive.
• Step 4: Dispensation of Medical Marijuana: Once the patient receives the medical marijuana card, the patient is then able to fill their first order for medical marijuana at a dispensary. The Medical Marijuana Use Registry will track patients' dose, frequency, type of medical marijuana received, and route of administration. After obtaining their medical marijuana card and filling their first dispensation, the investigators will track patients through MMTC and follow patients for 3 months post medical marijuana initiation.

Control Group Recruitment. Control participants will be age, race, and sex matched adults 50 and older with a diagnosis of chronic or severe pain recruited from the community using flyers/handouts; newspaper/Internet advertisements; in-person lectures and events; and contact via mail, e-mail, and the infrastructure and support of Oak Hammock at the University of Florida (UF), a residential retirement community. The investigators will also phone individuals enrolled in the UF HealthStreet and Clinical and Translational Science Institute's (CTSI) Integrated Data Repository, a database organizing clinical information across UF Health's clinical and research programs.