NATION More potent pot spurs a rise in dependence among adults

The increase was most notable among minorities.
SCRIPPS HOWARD
In a trend apparently caused by more potent pot, the prevalence of marijuana abuse or dependence among adults increased markedly through the 1990s, even though the percentage of people using the drug stayed about the same, according to a new government study.
The increases were particularly notable among young black men and women and young Hispanic men.
"Overall, marijuana abuse or dependence rose by 22 percent between 1991-92 and 2001-02," said Dr. Wilson Compton, director of prevention research at the National Institute on Drug Abuse and lead author of the study published today in The Journal of the American Medical Association. "This means there were approximately 800,000 more adults in the United States with marijuana abuse or dependence at the end of the period."
Across the adult population, about 4 percent were marijuana users during the past decade, but the prevalence of those with abuse problems rose from 1.2 percent to 1.5. percent.
Criteria
The criteria for abuse included failing to fulfill major obligations because of drug use, smoking pot in physically hazardous situations and having repeated legal problems because of drug use.
Respondents were determined to be dependent if they needed increased amounts of the drug to achieve a high, spent a great deal of time obtaining, using or recovering from effects of the drug and gave up important aspects of life in favor of using marijuana.
"It is important to communicate that the increased potency of marijuana over the past decade may, in part, be responsible for increases in abuse and dependence among users," Compton and his colleagues noted.
The study was based on results from two national substance abuse surveys, each of about 43,000 people over age 18, done 10 years apart, by the National Institute on Alcohol Abuse and Alcoholism.
While marijuana problems were considerably more common among whites a decade ago, this disparity had narrowed considerably by 2001-02. That was mainly because of increases of 224 percent among black men and women ages 18-29, from 1.4 percent with abuse problems to 4.5 percent, and a 148 percent among young Hispanic men (18-29) from 1.9 percent to 4.7 percent.
About the study
The study is the first to measure long-term trends in marijuana abuse and dependence in this country using a diagnostic system developed by the American Psychiatric Association.
"Marijuana is the most commonly used illegal substance in the United States, and its use is associated with poor educational achievement, reduced workplace productivity, motor vehicle accidents and increased risk for use of other substances," said Dr. Nora Volkow, director of the drug abuse institute.
"The study suggests that we need to develop ways to monitor the continued rise in marijuana abuse and strengthen existing prevention and intervention efforts," Volkow said, "particularly new programs that specifically target African-American and Hispanic young adults."