According to researchers from Columbia University’s Mailman School of Public Health, the daily use of marijuana in states that have legalized the drug is rising. The results of the study are published in Prevention Science online.
The researchers have said that daily use of marijuana as well as past month rates rose for both men and women aged 26 and older in states with medical marijuana laws in effect. For users under the age of 26 however, the use was unaffected by the changes in the laws.
Researchers used state-level survey data from the National Survey on Drug Use and Health for the years 2004-2013. The data included more than 17,500 youth, 17,500 young adults, and 18,800 adults, who were 26 and older.
The study found that in states with medical marijuana laws, daily marijuana use for male users age 26 and older increased from 16.3 percent to 19.1 percent. For women the increase was from 9.2 percent to 12.7 percent.
Past month use among men 26 and older increased from 7.0 percent before the laws passed to 8.7 percent following their passage, and for women it increased from 3.0 percent before to 4.3 percent after.
Christine Mauro, PhD, the first author on the study stated, “Among past month users, more than one in five young men ages 18-25 living in states with medical marijuana laws said they used marijuana every day.”
“The advent of medical marijuana laws has been proposed as one potential cause of the increased prevalence of marijuana use, but there is now a general consensus that passage of the laws has not affected rates of use in adolescents,” said Silvia Martins, MD, PHD, a senior author.
“Because most states in our sample more recently passed medical marijuana laws, it is possible that not enough time has elapsed to observe more significant changes in marijuana use disorder across age-gender subgroups,” remarked Mauro.
“Given the impact the disorder may have on individuals, families and society, marijuana use should continue to be monitored regularly. Building the evidence base by age and gender is critical in helping public health professionals better understand which groups, may be most affected by medical marijuana laws and target public health programming accordingly.”