Opioids were associated with more risks than were other analgesics in elderly patients who took the drugs for arthritis pain, according to a report in the journal.
Although NSAIDs are known to pose certain risks, the results of the study "support the safety of [NSAIDs] compared with other analgesics," said Dr. Daniel H. Solomon and his associates at Brigham and Women's Hospital, Boston.
Few studies have examined the relative risks of the three major analgesic groups: NSAIDs, opioids, and coxibs (selective cyclooxygenase-2 inhibitors). "Postmarketing surveillance data from usual care cohorts provide an opportunity to examine comparative safety across a wide range of events and can complement safety data from randomized controlled trials. However, imbalance in baseline population characteristics confounds many postmarketing surveillance studies," Dr. Solomon and his colleagues noted (Arch. Intern. Med. 2010;170:1968-78).
To compare safety, the researchers performed a propensity-matched cohort analysis using information from a Medicare database of pharmaceutical coverage for low-income elderly residents of Pennsylvania and New Jersey in 1999-2005. The study population included 12,840 adults with rheumatoid arthritis or osteoarthritis who began using one of the three types of analgesics during the study period and were followed for at least 1 year.
Adverse safety event rates were high for all three groups, and the rate of those events leading to hospitalization was greater than 100 per 1,000 person-years for all three types of analgesics.
Opioid users had the highest rates of serious adverse events. In particular, the rate of hip, pelvis, wrist, or humerus fractures was 101 per 1,000 person-years in the opioid group, compared with 19 per 1,000 person-years in the coxib group and 26 per 1,000 person-years in the NSAID group. A link between opioids and fractures had been reported previously, but "the strength of the association we observed is larger than in previous reports," the researchers said.
Compared with NSAIDs, opioids (hazard ratio, 1.77) and coxibs (HR, 1.28) were associated with elevated risk for cardiovascular events such as MI, stroke, heart failure, revascularization, and cardiac death. That "unexpected" finding regarding such severe events warrants further study, the investigators noted.
Compared with NSAIDs, risk for upper GI bleeding, lower GI bleeding, or bowel obstruction was similarly high for opioid users (HR, 1.07) but was lower for coxib users (HR, 0.60).
In general, opioid users experienced the most adverse events over time, whereas NSAID users experienced the fewest. In addition, "opioid users experienced moderate risk early in treatment," the investigators noted, while the other groups did not. Opioid users had significantly higher all-cause mortality (75 deaths per 1,000 person-years) than did either NSAID users (48 deaths per 1,000 person-years) or coxib users (47 deaths per 1,000 person-years). …