What about the role of marijuana in the WMAR incident? [Letter]

The recent incident of a man driving a truck into the WMAR television studio involved a person reported to suffer from mental illness and a cannabis use disorder, yet the press continues to hype up the mental health diagnosis and play down the substance abuse ("WMAR barricade suspect had been hospitalized for mental illness, mother says," May 14).

What will it take for people to understand that there is a high prevalence of co-occurring substance use and mental disorders? Yes, people may hear voices, but adding a substance to that can be fatal. On the other hand, people will take substances that induce psychotic behavior, which can have the same result.


Psychiatric Times published an article on Oct. 14, 2013 which stated that approximately 50 percent of patients with schizophrenia will have a co-morbid lifetime substance use disorder. Tobacco and cannabis are the most commonly used substances among these patients. Recent data show that cannabis misuse often occurs before the onset of psychosis and that psychotic and affective symptoms worsen after cannabis use.

Other research has found that schizophrenia and other psychoses are associated with violence and violent offending, particularly homicide. However, most of the excess risk appears to be mediated by substance abuse co-morbidity. The risk in these patients with co-morbidity is similar to that for substance abuse without psychosis. Public health strategies for violence reduction could consider focusing on the primary and secondary prevention of substance abuse.


If we don't soon get this right, it will never get fixed.

Patricia Bayly Miedusiewski, Monkton


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