Study: Marijuana Misuse Increased During 1990s

Although the number of people using marijuana remained about the same from 1991-1992 to 2001-2002, a new government study says that marijuana misuse and addiction increased substantially.

For the study, researchers from the National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse and Alcoholism used the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders IV to compare trends in marijuana use among the nation’s adult population during the two time periods.

“The results of our study show that use of marijuana remained stable in 2001-2002 compared to 1991-1992; however, there were significant increases in marijuana abuse or dependence, especially in certain minority subgroups,” said Dr. Wilson Compton, director of the Division of Epidemiology, Services and Prevention Research at NIDA. “Overall, marijuana abuse or dependence rose by 22 percent from 1991-1992 to 2001-2002. This means that there were approximately 800,000 more adults in the United States with marijuana abuse or dependence in 2001-2002.

“Furthermore, marijuana abuse or dependence was more common among whites than among minorities in 1991-1992, but by 2001-2002 the differences in abuse and dependence rates among the different ethnic groups had narrowed considerably,” said Compton. “This change was due to increases of 224 percent among young African-American men and women aged 18-29, and 148 percent among young Hispanic men aged 18-29.”

While the authors found no single factor for the increase in marijuana problems among minorities, they noted a reported increase in the potency of marijuana over the last decade.

“This study suggests that we need to develop ways to monitor the continued rise in marijuana abuse and dependence and strengthen existing prevention and intervention efforts, particularly developing and implementing new programs that specifically target African-American and Hispanic young adults,” said NIDA Director Dr. Nora Volkow.

The study’s findings are reported in the May 5 issue of the Journal of the American Medical Association (JAMA).