New Study: Estimating THC Risk Thresholds for Cannabis Use Disorder

UK researchers have attempted to estimate risk thresholds for cannabis use disorder (CUD) based on delta-9-tetrahydrocannabinol (THC) consumption, using standard THC units. Cannabis use disorder is a condition whereby a person demonstrates a pattern of use that causes negative impacts in their life, but they continue to use it. The USA’s Centers for Disease Control indicates approximately 3 in 10 people who use cannabis have CUD. The condition doesn’t just affect recreational users. Australian researchers found 25% of individuals using cannabis medicinally had CUD. For its CUD study, researchers from the UK’s University of Bath, King’s College and UCL drew on data from the CannTeen study, a longitudinal observational study that consisted of five assessments over a 12-month period. The researchers assigned 5 mg of THC as being one unit. This is the level being used by the United States National Institutes of Health, which requires the use/reporting of THC units in research Institutes funds. Of 177 CannTeen participants who used cannabis over the previous 12 months, DSM-5 CUD diagnosis was completed for 162 participants at the final follow-up. The DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) is the authoritative guide for mental health professionals such as psychiatrists and psychologist to classify and diagnose mental illnesses. These diagnoses found: No CUD (adult n = 30; adolescent n = 29) Any CUD (adult n = 35; adolescent n = 56) Moderate/severe CUD (adult n = 22; adolescent n = 44). Study findings state the optimal cut-offs for risk of any CUD (versus no CUD) were 8.26 units (41.3 mg) of THC per week for adults and 6.04 units (30.2 mg) per week for adolescents. For risk of moderate/severe CUD (versus no CUD) optimal cut-offs were 13.44 units (67.2) per week for adults and 6.45 units (32.25 mg) per week for adolescents. In their discussion of the study, the researchers say: “Determining risk thresholds for CUD based on quantity of THC could inform harm-reduction strategies to reduce the health burden of CUD. To our knowledge, this is the first study to estimate risk thresholds for CUD based on standard THC units.” And .. “These findings may help to feed into the development of lower-risk guidelines for cannabis use, to aid those who use cannabis and wish to reduce their risk of harm by choosing to consume less THC than the above thresholds per week.”