Study: Fewer Marijuana Consumers Meeting ‘Dependence’ Criteria

Santa Monica, CA: The percentage of daily cannabis users who meet the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) criteria for dependence has fallen significantly over the past decade and a half, according to data published in the journal Drug and Alcohol Dependence.

Data compiled by a researcher at the RAND Corporation reports, “[R]isk of dependence formation among heavy marijuana users appears to have declined since 2002” – from roughly one-in-four to one-in-six. The author acknowledges that this decline coincides with a period of liberalized cannabis laws, as well as an overall increase in adult marijuana use.

Rates of dependence also fell sharply among past-year marijuana users – from 13.8 percent to 8.5 percent – during this same period of time.

The DSM-IV defines cannabis ‘dependence’ as: failing to keep limits set on one’s cannabis use; reducing one’s engagement in important activities; continuing to use the substance despite ongoing emotional, physical, or emotional problems; spending an inordinate amount of time obtaining cannabis, and failing to reduce one’s use despite intending to do so.

Separate studies, such as those here and here, have previously reported similar decreases in rates of problematic cannabis use among teens.

For more information, contact Paul Armentano, NORML Deputy Director, at: paul@norml.org. Full text of the study, “Falling rates of marijuana dependence among heavy users,” appears in Drug and Alcohol Dependence.