Opium use linked to almost double the risk of death from any cause
Long term opium use, even in relatively low doses, is associated with almost double the risk of death from many causes, particularly circulatory diseases, respiratory conditions and cancer, concludes a study published in the British Medical Journal today.
The findings remind us not only that opium is harmful, but raise questions about the risks of long term prescription opioids for treatment of chronic pain.
The research was carried out in northern Iran, where opium consumption is exceptionally common, and is the first study to measure the risks of death in opium users compared with non-users.
Around 20 million people worldwide use opium or its derivatives. Studies suggest a possible role of opium in throat cancer, bladder cancer, coronary heart disease and a few other conditions, but little is known about its effect on overall mortality, particularly for low-dose opium used over a long period
So an international research team set out to investigate the association between opium use and subsequent risk of death.
They studied opium use among 50,045 men and women aged 40 to 75 years living in Golestan Province in northern Iran for an average of five years.
A total of 17% (8,487) participants reported opium use, with an average duration of 12.7 years. 2,145 deaths were reported during the study period.
After adjusting for several factors including poverty and cigarette smoking, opium use was associated with an 86% increased risk of deaths from several major causes including circulatory diseases, asthma, chronic obstructive pulmonary disease (COPD), tuberculosis and cancer.
Even after excluding those who self-prescribed opium after the onset of a chronic illness, the associations remained strong and a dose-response relationship was seen.
Increased mortality was seen for different types of opium. Both opium ingestion and opium smoking were associated with a higher risk of death.
Assuming this represents a direct (causal) association, the authors estimate that 15% of all deaths in this population are attributable to opium. They call for more studies on opium use and mortality and of patients taking long term opioid analgesics for treatment of pain to help shed further light on this issue.
"In a linked editorial, Assistant Professor Irfan Dhalla from St Michael's Hospital in Toronto says that in high income countries doctors rarely, if ever, encounter someone who uses opium. However he warns that millions of patients with chronic pain are prescribed opioids such as morphine and codeine that may carry "risks that are incompletely understood."