GO TO CMA Home
GO TO Inside CMA
GO TO Advocacy and Communications
GO TO Member Services
GO TO Publications
GO TO Professional Development
GO TO Clinical Resources

GO TO What's New
GO TO Contact CMA
GO TO Web Site Search
GO TO Web Site Map


CMAJ
CMAJ - June 13, 2000JAMC - le 13 juin 2000

Self-reported medical use of marijuana: a survey of the general population

Alan C. Ogborne, Reginald G. Smart, Edward M. Adlaf

CMAJ 2000;162:1685-6

The issue of medical marijuana use has been on the forefront of public debate. There are indications that marijuana is sometimes used to alleviate pain from cancer, to reduce nausea from chemotherapy, to mitigate the wasting syndrome of AIDS, and for the treatment of glaucoma, epilepsy, multiple sclerosis and a variety of other disorders.1,2 A few studies have suggested that the medical use of marijuana is common among people with HIV/AIDS3,4 and those with certain psychiatric conditions.5,6 However, there are no published surveys of such use among people with other conditions. We report results from the only general population survey known to have included questions about the medical use of marijuana. The survey involved telephone interviews with Ontario adults aged 18 years or more. Interviews were completed with 2508 people (67.4% of the 3723 households in which a household member answered the call). For this report we weighted the responses to account for differential selection related to regional stratification and household size.7

In the weighted sample 49 respondents (1.9%) reported using marijuana for a medical reason in the year preceding the survey (Table 1). A total of 173 other respondents (6.8%) reported using marijuana but not for medical reasons. (The corresponding numbers in the unweighted sample were 47 and 142.) The remaining 2305 respondents (91.2%) in the weighted sample reported no use of marijuana in the preceding year. The most frequently cited reason for using marijuana medically was for pain or nausea (41/49 [85%]). A variety of other uses were reported by a few respondents.

Compared with nonusers, those who used marijuana for any reason tended to be younger, more likely to have alcohol problems and more likely to have used cocaine in their lifetime (Table 1). Those who reported using marijuana for a medical reason were similar to the other users but were more likely to have used cocaine. A multinominal analysis showed that both groups of users differed from the nonusers in age, lifetime use of cocaine and scores on the 10 items of the Alcohol Use Disorders Test (AUDIT) for detecting harmful alcohol consumption.8 However, a similar analysis showed that the only statistically significant difference between the 2 groups of marijuana users was in reported lifetime use of cocaine. Among the respondents who used marijuana for medical reasons, those with no history of cocaine use and an AUDIT score of less than 8 did not differ significantly from the other users with respect to age, sex, marital status or cigarette smoking (an AUDIT score of 8 or more indicates hazardous or harmful use of alcohol).

The finding that about 2% of the population could claim the right to use marijuana for medical reasons, based on self-identified needs, challenges the development of a system to ensure access to quality-controlled marijuana for medical use and could fuel arguments for decriminalization of marijuana for personal use. However, a more restricted definition of medical marijuana use based on clinical indicators rather than self-identified needs may not completely satisfy existing demands.

As in other population studies,9 the use of marijuana for any reason was associated with male sex, relative youth, cigarette smoking, heavy drinking, alcohol problems and cocaine use. Those who used marijuana for medical reasons were generally similar to the other marijuana users but were more likely to have used cocaine. Further research is needed to determine whether experiences with alcohol and other drugs and other lifestyle factors influence motivations for marijuana use and beliefs in its medical benefits.

The views expressed in the article are those of the authors and do not necessarily represent those of the Centre for Addiction and Mental Health.

Competing interests: None declared.

Comments Send a letter to the editor
Envoyez une lettre à la rédaction

Dr. Ogborne is with the Centre for Addiction and Mental Health, London, Ont. Drs. Smart and Adlaf are with the Centre for Addiction and Mental Health, Toronto, Ont. Dr. Adlaf is also with the Department of Public Health Sciences, University of Toronto, Toronto, Ont.

This article has been peer reviewed.

Reprint requests to: Dr. Alan C. Ogborne, Centre for Addiction and Mental Health, 200­100 Collip Circle, London, ON N6G 4X8; ogborne@julian.uwo.ca

References
  1. Grinspoon L, Bakalar JB. Marijuana, the forbidden medicine. London: Yale University Press, New Haven and Yale; 1997.
  2. Harris D, Mendelson JE, Jones RT. A survey of 100 Medical Marijuana Club Members [abstract]. In: Harris LS, editor. Problems of drug dependence, 1998: proceedings of the 60th Annual Scientific Meeting, the College on Problems of Drug Dependence, Inc. [NIDA research monograph series, no 179]. Rockville (MD): US Department of Health and Human Services, National Institutes of Health and National Institute on Drug Abuse; 1999. p. 313.
  3. Fairfield KM, Eisenberg DM, Davis RB, Libman H, Phillips RS. Patterns of use, expenditures, and perceived efficacy of complementary and alternative therapies in HIV-infected patients. Arch Intern Med 1998;158:2257-64. [MEDLINE]
  4. Dansak DA. Medical use of recreational drugs by AIDS patients. J Addict Dis 1977;16:25-30.
  5. Beesley S, Russell A. Cannabis use in a general psychiatric population. Scott Med J 1997;42:171-2. [MEDLINE]
  6. Mathers DC, Ghodse AH, Caan AW, Scott SA. Cannabis use in a large sample of acute psychiatric admissions. Br J Addict 1991;86:779-84. [MEDLINE]
  7. Adlaf EM, Ivis FJ, Paglia A, Ialomiteanu A. The Ontario drug monitor, 1998: technical guide [CAMH research document series, no 3]. Toronto: Centre for Addiction and Mental Health; 1999. p. 10.
  8. Saunders JB, Aasland OG, Babor TF, de la Fuente JR, Grant M. Development of the Alcohol Use Disorders Test (AUDIT): WHO Collaborative Project on the early detection of persons with harmful alcohol consumption. Addiction 1993;88:791-804. [MEDLINE]
  9. Ogborne AC, Smart RG. Cannabis users in the general Canadian population. Subst Use Abuse 2000;35:301-11.

© 2000 Canadian Medical Association or its licensors