Search Here

For those dependent on opioids, the risk of death was 5.71 times higher than healthy individuals in the population of the same age, gender and race.

People with an opioid addiction had the highest risk of death when compared with rates for alcohol and other drugs, a new study by the Centre for Addiction and Mental Health (CAMH) found. Those with methamphetamine use disorders were next highest with a 4.67-fold risk, followed by those with addictions to cannabis (3.85), alcohol (3.83) and cocaine (2.96). Alcohol dependence was related to the highest number of deaths overall. 

"One reason for undertaking this study was to examine whether methamphetamine posed a particular threat to drug users, as it has been called  'America's most dangerous drug,'" said CAMH Scientist Dr. Russell Callaghan, who led the study. "The risk is high, but opioids are associated with a higher risk. We also wanted to compare mortality risks among several major drugs of abuse, as this comparison hasn't been done on this scale before."

The study, available online in the journal Drug and Alcohol Dependence, is the largest North American study to compare mortality rates among different  drug users with the longest follow-up. It tracked records of more than 800,000 California inpatients with a diagnosis of methamphetamine, alcohol, opioid, cannabis or cocaine-related disorders between 1990 and 2005. The inpatient records were then matched to death records from the California Vital Statistics Database. Rates were adjusted by age, sex and race to the California population in 2000. Of this group, more than 188,000 died during this period.

The findings mean that if 10 individuals in the general population died, then over the same period there would be 57 deaths among people dependent  on opioids, which includes prescription opioids as well as heroin.

"One surprising finding was the high rate of death among cannabis users," said Dr. Callaghan. "There could be many potential reasons, including the  fact that they may have other chronic illnesses such as psychiatric illnesses or AIDS, which can also increase the risk of death."

The findings point to the importance of brief interventions for people receiving medical care for drug dependence on other related risks such as infectious diseases or injuries, Dr.Callaghan said.