While average life expectancy has been rising steadily in most countries over the past century, new research led by the Centre for Addiction and Mental Health (CAMH) shows that life expectancy declined significantly and rapidly in three countries where policy changes increased access to prescription opioids, alcohol or illicit drugs. Published in BMC Medicine, the study underscores the need for effective substance use policies and public health interventions, and provides key principles to guide policy decisions.
"Our study shows that failed substance use policies can reverse life expectancy trends for large population groups or even countries," says Dr. Jürgen Rehm, Director of Social and Epidemiological Research at CAMH and first author of the study. "On the other hand, we also observed that effective policy changes are associated with substantial gains in life expectancy."
The researchers investigated marked changes in life expectancy linked to substance use and related policies in three countries: the U.S., the former Union of Soviet Socialist Republics (USSR) and Mexico.
In the U.S., prescription opioids are used in larger quantities than in any other country. Usage started increasing rapidly in the mid-1990s, partly as a result of allowing family doctors to prescribe short-acting opioids such as oxycodone for chronic pain and other relatively common diseases. Non-medical use of these substances and associated harms, including overdose deaths, increased alongside prescription use. From 1999 to 2013, mortality increased by nine per cent in middle-aged white non-Hispanic Americans, despite life expectancy continuing to rise among other U.S. populations, including Hispanic and black non-Hispanic populations.
"Canada is second in the world only to the U.S. in our rates of prescription opioid use, and the rise of prescription opioids in our provinces has also shown to be strongly linked to overdose deaths," cautions Dr. Rehm, who is also Head of the World Health Organization/Pan-American Health Organization (WHO/PAHO) Collaborating Centre in Addiction and Mental Health at CAMH. Consumption of prescription opioids in Canada rose steeply from 2000 to 2010. "Comprehensive and integrated policies are needed to avoid these harms, and decreasing availability is key. The new guidelines for prescribing of the Centers for Disease Control and Prevention in the U.S. are exemplary, and we need similar public health-oriented guidelines in Canada."
The study also found that, in the USSR, after years of declines, life expectancy increased by 3.2 years for men and 1.3 years for women from 1984 to 1987 as policy reduced the supply of alcohol. But, between 1987 and 1994, as restrictive alcohol policy was abandoned and alcohol became widely available, life expectancy fell by 7.3 years for men and 3.3 years for women.
"These dramatic cases show that changes in policies -- and ensuing changes in substance use -- can affect life expectancy, not only over the long term, but abruptly," says Dr. Rehm. "The example of the USSR shows that policy changes can lead to positive or negative outcomes."
The researchers outline several key principles as recommendations to guide policy development, including:
- Actively monitoring disease burden and mortality attributable to substance use in order to identify and respond when rapid changes in life expectancy occur.
- Creating integrated substance use policies that consider public health as a whole.
- Decriminalizing substance use, and regulating the availability and affordability of substances.
Among their recommendations, the researchers also cite the need to provide access to treatment and social assistance for heavy users and their families, and to reduce the stigma associated with substance use, which acts as a barrier to seeking treatment. "Substance use disorders are the least treated mental conditions," says Dr. Rehm.
Centre for Addiction and Mental Health