According to research published in the Annals of Internal Medicine, patients receiving higher doses of prescribed opioids are at increased risk for overdose.

Researchers evaluated the association between opioid overdose and its relation to the average prescribed daily opioid dose among patients receiving medically prescribed long-term opioid therapy.

The average daily opioid dose (using morphine equivalents) over the previous 90 days from automated pharmacy data were evaluated and the primary outcome of fatal and non-fatal overdoses were identified through diagnostic codes from inpatient and outpatient care and death certificates.

The patient population involved were 9,940 patients who received 3 or more opioid prescriptions within 90 days for chronic noncancer pain. A total of 51 opioid-related overdoses were identified, including 6 deaths. The following results were reported:
• Compared with patients receiving 1 to 20 mg/d of opioids (0.2% annual overdose rate), patients receiving 50 to 99 mg/d had a 3.7-fold increase in overdose risk (95% CI, 1.5 to 9.5) and a 0.7% annual overdose rate
• Patients receiving 100 mg/d or more had an 8.9-fold increase in overdose risk (CI, 4.0 to 19.7) and a 1.8% annual overdose rate.

The authors also concluded that patients receiving a higher dose of prescribed opioids should be closely supervised.
A related editorial discusses the study.