1. Marijuana Use Disorders in the United States: 1991-1992 and 2001-2002 Wilson M. Compton, M.D., M.P.E. Director, Division of Epidemiology, Services and Prevention Research National Institute on Drug Abuse Department of Health and Human Services May 5, 2004 American Psychiatric Association Annual Meeting

2. Background A great deal of information about trends in use of drugs is available, but no data provides reliable and valid measures of drug disorders over the past decade.

3. Background With data from two large household surveys of the U.S. adult population, this study seeks to answer the following questions: 1.What are the rates of marijuana abuse and dependence in 1991-1992 compared to 2001-2002? 2.Have the relationships of age, race/ethnicity or gender to marijuana abuse and dependence changed during this period?

4. Methods Studies: Large studies of the U.S. non-institutionalized household adult (18+) population conducted by the Census Bureau. NLAES: National Longitudinal Alcohol Epidemiologic Study (N = 42,862) NESARC: National Epidemiologic Study of Alcohol and Related Conditions (N = 43,093)

5. Methods Interview: AUDADIS: Alcohol Use Disorder and Related Disabilities Interview Schedule - DSM-IV Version –Specific measures of each criterion of abuse and dependence on marijuana –Reliability and validity well-established

6. Methods Outcomes Marijuana use, abuse and dependence in overall population and by age, race/ethnicity and sex Marijuana abuse and dependence among marijuana users by age, race/ethnicity and sex

7. Results: Total Population = p <.05 %

8. Results: Total Population Comparing 1991-1992 to 2001-2002: Marijuana use rates were virtually the same: 4.0% versus 4.1% Marijuana abuse or dependence increased from 1.2% to 1.5% (p =.014) Marijuana abuse or dependence among users increased from 30.2% to 35.6% (p <.01) How consistent are these results across age groups, race/ethnic groups and sexes?

9. Results: Marijuana Use by Sex and Race/Ethnicity = p <.05 %

10. Results: Marijuana Use In Age Groups = p <.05 %

11. Results: Marijuana Use in Whites = p <.05 %

12. Results: Marijuana Use in Blacks = p <.05 %

13. Results: Marijuana Use in Hispanics = p <.05 %

14. Results: Marijuana Use in Men = p <.05 %

15. Results: Marijuana Use in Women = p <.05 %

16. Use increased significantly for: –White males 45-64 years old –Black females overall and Black females 18-29 and 46-64 years old –Hispanic females 18-29 years old Results: Marijuana Use in Detailed Age- Sex-Race/Ethnicity Categories

17. Rates did not change significantly overall Rates increased significantly for: –18-29 and 45-64 year olds –Black and Hispanic 18-29 year olds –White and Black 45-64 years olds –Women 18-29 years old and both men and women 45-64 years old –Selected age-sex-race/ethnicity categories Results: Summary of Marijuana Use

18. Results: Marijuana Abuse or Dependence in Overall Population = p <.05 %

19. Results: Marijuana Abuse or Dependence by Sex and Race/Ethnicity = p <.05 %

20. Results: Marijuana Abuse or Dependence in Whites = p <.05 %

21. Results: Marijuana Abuse or Dependence in Blacks = p <.05 %

22. Results: Marijuana Abuse or Dependence in Hispanics = p <.05 %

23. Results: Marijuana Abuse or Dependence in Men = p <.05 %

24. Results: Marijuana Abuse or Dependence in Women = p <.05 %

25. Rates increased significantly overall Increases in rates were significant for: –18-29 and 45-64 year olds overall –Blacks and Hispanics overall and 18-29 years old –Women overall and 18-29 years old –Men 45-64 years old –Black and Hispanic men overall and 18-29 years old –Black women overall and 18-29 years old Results: Summary of Marijuana Abuse or Dependence

26. Results: Marijuana Abuse or Dependence Among Users in Overall Population = p <.05 %

27. Results: Marijuana Abuse or Dependence among Users, by Sex and Race/Ethnicity = p <.05 %

28. Results: Marijuana Abuse or Dependence Among Black Users = p <.05 %

29. Results: Marijuana Abuse or Dependence Among White Users = p <.05 %

30. Results: Marijuana Abuse or Dependence Among Hispanic Users = p <.05 %

31. Results: Marijuana Abuse or Dependence Among Male Users = p <.05 %

32. Results: Marijuana Abuse or Dependence Among Female Users = p <.05 %

33. Rates increased significantly overall Increases in rates were significant for: –18-29 and 30-44 year olds overall –Blacks overall and 30-44 and 18-29 years old –Hispanics overall and 18-29 years old –Women and men overall and 18-29 years old –Black and Hispanic men overall and 18-29 years old –Black women overall and 18-29 years old Results: Summary of Marijuana Abuse or Dependence Among Users

34. Estimated Population Increases in Marijuana Abuse or Dependence MaleFemale White Black Hispanic Other Total

35. Why have rates increased? Changes in quantity/frequency of marijuana use? Changes in potency of marijuana? Psychosocial factors?

36. Why have rates increased? Changes in quantity/frequency of marijuana use? Not likely…

37. Changes in Frequency of MJ Use? %

38. Changes in Quantity of MJ Smoked? %

39. Why have rates increased? Changes in potency of marijuana? Possibly …

40. Changes in Potency of Marijuana Source: Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi; 2003

41. Why have rates increased? Psychosocial factors? Possibly…

42. Plausible Psychosocial Factors Acculturation? Lifestyle factors and attitudinal factors? Sociodemographic or socioeconomic factors? Economic factors such as price, tax and policy changes affecting other substances that may inadvertently affect marijuana? Historical and cultural factors?

43. Summary Rates of Marijuana use were nearly the same in the total population in 1991-1992 as in 2001-2002, but increases were seen in certain subgroups: –younger male and female blacks, –younger Hispanic males –white and black 45-64 year olds.

44. Marijuana-related disorders (abuse and dependence) increased from 1991-1992 to 2001-2002, especially for younger male and female blacks and younger hispanic males. Increased potency of marijuana may play a role Summary

45. Marijuana Use Disorders in the United States: 1991-1992 and 2001-2002 Wilson M. Compton, M.D., M.P.E. - NIDA Bridget F. Grant, Ph.D., Ph.D. - NIAAA James D. Colliver, Ph.D. - NIDA Meyer D. Glantz, Ph.D. - NIDA Frederick S. Stinson, Ph.D. - NIAAA