US marijuana use, disorders doubled since 2001: Study

A man smokes cannabis in Portland, Oregon, on October 4, 2015. (AFP photo)

The proportion of adults in the United States using and abusing marijuana at least doubled between 2001 and 2013, rising to about 22 million people, according to a new study.

About 4 percent of adults in 2001 and 2002 reported having used the  illicit drug, compared to about 10 percent in 2012 and 2013, according to researchers at Columbia University in New York City.
Similarly, 1.5 percent of adults reported abuse or dependence problems in 2001 and 2002, compared to about 3 percent from 2012 to 2013, said the study, which was published Wednesday in the journal JAMA Psychiatry.
“What was quite clear is the prevalence of use among adults had more than doubled,” said Deborah Hasin, the study’s lead author from Columbia University.
Although marijuana dependence and abuse was found to be on the rise, that is largely due to the overall increase in new users, the researchers wrote.
There were especially significant increases among women, African Americans, Hispanics and people between the ages of 45 and 64, as well as people living in the South or those with lower-income.
The results come from a comparison of health surveys from 2001-02 and 2012-13 sponsored by the National Institutes of Health.
The long-term use of cannabis, also known as marijuana, has a number of adverse effects including contributing to psychosis, anxiety, depression, schizophrenia and an increased incidence of suicide.
The large increase comes as attitudes and laws in the US have become more tolerant of marijuana.
A majority of Americans, 58 percent, continue to say marijuana use should be legal in the United States, according to Gallup poll released Wednesday.
Furthermore, 23 US states have legalized medical marijuana use, and four also allow recreational use.
The latest report comes as US President Barack Obama has unveiled a new initiative to tackle the heroin crisis across the United States.
More than 8,250 people a year now die from heroin overdose, while roughly double that number are dying from prescription opioid painkillers.
Over 37,000 Americans died of a drug overdose in 2013 alone, according to the US Centers for Disease Control and Prevention (CDC).