Geographical variation in the prevalence of problematic substance use in Canada

Aug 22 2007

If you think the big cities of Toronto and Montreal have the highest rate of alcohol and drug use problems, think again.

A new study entitled "Geographical Variation in the Prevalence of Problematic Substance Use in Canada authored by three researchers from the Centre for Addiction and Mental Health (CAMH) discovered that Ontario and Quebec had markedly lower concentrations of people with alcohol and drug problems.

With a Canada-wide prevalence of substance use problems estimated at 11%, the study found that estimates were particularly low in the urban corridor between Toronto and Montreal. This low level of alcohol and drug use problems contrasts with higher rates in both the eastern and western provinces of Canada. Nova Scotia, Manitoba, Saskatchewan, Alberta and British Columbia were all significantly higher than the national average.

Prevalence is higher in mid-sized cities than in larger ones or in rural areas. Although age, sex, employment, and physical health are all strongly associated with substance use problems, these factors did not explain the regional differences.

The CAMH researchers discuss a number of explanations for their findings. "Major cities include large numbers of immigrants, among whom drug and alcohol problems are less common. People who decide to come to Canada, and are accepted, tend to be healthy and high-functioning, and some immigrant cultures also reject alcohol and drug use," said Scott Veldhuizen, Research Analyst at CAMH. The study's co-authors are CAMH Dr. John Cairney, Research Scientist and Project Scientist Karen Urbanoski.

Other possible factors discussed include migration within Canada, differences in the availability of alcohol or illicit drugs, the accessibility of treatment, the local culture, and local policies. While pointing to the role of social context in the development or remission of problem substance use, the authors also cite existing work on the potential effect of living at higher latitudes on the development of drug and alcohol problems.

"The pattern of large-scale differences is probably part of a larger disparity among regions in Canada. Research has already shown that levels of crime and other social problems are somewhat higher in western Canada, and this may be part of the same pattern. A role for latitude is possible , there is already some evidence of a link with depression, which often occurs with substance use problems , but this is an area where more work needs to be done," Veldhuizen commented.

As well as pointing out some clear directions for future research, the study also concludes the need for policy that is flexible and locally relevant.

http://www.camh.net