Links to an increase in schizophrenia alone could wipe out any revenues from legalized pot, new study says
Legalization of marijuana would lead to an increase in mental illness, including schizophrenia, and thereby increase the tax burden on Vermonters by an estimated $4.9 to $11.1 million dollars, according to a white paper issued today by Smart Approaches to Marijuana in Vermont (SAM-VT). The costs would offset the estimated $7.4 million in revenue to be generated by the sales, based on the recreational marijuana revenue seen by Colorado in 2014. Future increases in consumption would increase the taxes collected, but only to be counterbalanced by the associated increases in social costs.
The white paper, co-authored by Christine Miller, Ph.D., a pharmacologist specializing in neuroscience, takes to task the major report used to support the legalization movement for failing to account for documented and well-researched links between marijuana use and mental health disorders, and the costs of treating them. Miller says that the report, done by the RAND Corporation, dismissed research into the links between marijuana use and mental illness by claiming any population effects of marijuana on the psychoses are likely to be small and further asserting the causal relationship between marijuana and psychosis has not yet been proven.
But, says Miler, the size of the population affected depends on how many are exposed to how much. According to research out of Britain published recently in Lancet Psychiatry, use of high potency marijuana can be considered causal for nearly one quarter of recent onset psychosis cases in the UK, a figure no one in the mental health field would regard as small. Similar studies on poor health outcomes from tobacco and alcohol use moved society to try to limit rather than increase their presence in our culture, without waiting for the exact mechanism of causation to be fully understood.
The RAND authors are correct that it is difficult to calculate the social costs of using psychoactive drugs, but it is possible; in fact, such calculations have been made for alcohol and tobacco use for years, Miller and co-author Dean Whitlock, a Vermont writer, state. The calculations are not perfect, in the same way that the RAND Report’s calculations of the potential pot market are not perfect, requiring the specification of wide margins of error.
The white paper quotes Dr. John Hughes, a UVM researcher who has studied marijuana and tobacco use for decades, who wrote that the criticism of marijuana studies is true of over 80% of data on health risks.
All, yes all, the data we have on whether smoking is harmful is from non-randomized trials. Dr. Hughes says. I think most scientists would conclude that recreational use [of marijuana] is harmful.
Miller and Whitlock cite more than three dozen studies, pointing out that the American Psychiatric Association links several mental health disorders with Cannabis Use Disorder. These include: anxiety disorders, major depressive disorder (and suicide attempts), bipolar I disorder, antisocial disorder, obsessive-compulsive disorder, and psychotic disorders.
Treatment of these mental health problems in general, and of schizophrenia in particular, can bankrupt families and require significant expenditures of state health dollars, the report concludes. The white paper projects an estimated additional cost of $4.9 to $11.1 million per year for the treatment of schizophrenia alone, based on the increase in marijuana consumption predicted by the RAND report. According to Miller and Whitlock, schizophrenia likely costs the state about $200 million annually, with an estimated $20.6 million attributable to marijuana use having precipitated the condition.
The white paper also notes that the 2013 results of Vermont’s Youth Risk Behavior Survey, administered every two years in the state’s middle schools and high schools, show a striking correspondence between suicide attempts and the rate of marijuana use.
Any so-called benefits of legalizing marijuana are far outweighed by the costs, says Miller. Vermont’s human services system is already overwhelmed and legalization will certainly only increase the burden.
