Researchers from the Department of Psychology at the University of Minnesota in the USA explore the psychological and social problems of regular cannabis users. They wanted to look into two different user groups – users with a cannabis use disorder and users without a cannabis use disorder. The study was published in Psychological Medicine in November 2017. The researchers compared psycho-social functioning across the two groups. They did it to find out whether adolescents who use cannabis regularly without ever developing a cannabis use disorder experience notable psycho-social impairment. They used a non-user control group during adolescence and young adulthood.
Significantly higher levels of substance use problems
Participants were recruited from the Minnesota Twin Family Study. There were three groups enrolled in the study. One group who used cannabis on a weekly basis with a cannabis use disorder, one group who used cannabis on a weekly basis without a cannabis disorder, and one group that didn’t use cannabis. The three groups were compared on alcohol and illicit drug use, psychiatric problems, personality and social functioning at age 17 and from 18 to 25 years of age. In both adolescence and young adulthood, cannabis users without a disorder reported significantly higher levels of substance use problems and externalizing behaviors than non-users. However, their levels were lower than users with a cannabis use disorder.
High degree of agreement between twins
The researchers concluded that the need for early prevention and intervention is important. This is regardless of whether or not the adolescents have a cannabis use disorder. They came to that conclusion based on the results that indicate that even in the absence of a cannabis use disorder, regular cannabis use is associated with psycho-social impairment in adolescence and young adulthood. The researchers also found that there was a high degree of agreement between the problems the adolescents described to be experiencing and what their co-twin observed.
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