WASHINGTON (TIP): Marijuana use in the US more than doubled between 2001 and 2013 – from 4.5 to nearly 10%, according to new research. Laws and attitudes about marijuana are changing, with 23 states having medical marijuana laws and four of these states having also legalised marijuana for recreational use, researchers said.

Bridget F Grant of the National Institute on Alcohol Abuse and Alcoholism, and coauthors used nationally representative data on past-year prevalence rates of marijuana use, marijuana use disorder and marijuana use disorder among marijuana users in the US.

The prevalence of past year marijuana use climbed to 9.5% of adults in 2012-2013 from 4.1% in 2001-2002, with increases particularly notable among women and individuals who were black, Hispanic, middle-aged or older, the authors said.

The prevalence of a diagnosis of a past-year marijuana use disorder (abuse or dependence) also increased to 2.9%in 2012-2013 from 1.5% in 2001-2002, implying nearly 3 of every 10 Americans using marijuana in the past year had a diagnosis of a marijuana use disorder (approximately 6.8 million Americans).

Among marijuana users, the prevalence of marijuana use disorder decreased to 30.6% in 2012-2013 from 35.6% in 2001-2002.

Because there was no increase in the risk for marijuana use disorder found among users, in fact there was a decrease, the increase in prevalence of disorders can be attributed to the increase in marijuana users between the two surveys, the authors said. (Source : PTI)