Effects of medical cannabis use on physical and psychiatric symptoms across the day among older adults.

Introduction: Older adults are increasingly using medical cannabis (MC). It is unclear if therapeutic effects increase problematic use patterns. The current study addresses this issue by examining symptom trajectories across the day and using trajectories to predict problematic use.

Methods: One-hundred six older adults (age range 55-74) who endorsed medical conditions approved for treatment using MC were recruited online. Participants received six text messages/day to assess momentary symptoms for 15 days.

Results: Participants provided 5,156 momentary assessments across 1,106 use days. Symptom trajectories were examined across the day. There was a decline in all symptoms following use. Negative affect, pain, and nausea evinced momentary negative reinforcement associations with cannabis intoxication. Momentary negative reinforcement was associated with adverse cannabis outcomes. Declines in post-use trauma symptoms and momentary negative reinforcement effects for negative affect were both associated with cannabis use disorder symptoms.

Discussion: These data suggest that MC may be effective in reducing common symptom clusters. However, the negative reinforcing effect (i.e., the link between use and symptom relief at the event level) may complicate the therapeutic nature (i.e., symptom reduction). Identifying interventions to maximize benefits while minimizing costs may increase the efficacy and safety of MC in older adults.