Investigating the safety of analgesics in older adults with arthritis

Despite common usage, comparative safety levels of analgesics not clearly established
The rate for analgesics usage in the U.S. is staggeringly high, with 1 in 5 adults receiving a prescription for them in 2006. Yet somehow, despite their massive popularity, the comparative safety of these types of drugs is not fully understood. While the cardiovascular safety of nonselective non-steroidal anti-inflammatory drugs (NSNSAIDs) and selective cyclooxygenase-2 inhibitors (coxibs) have at least been called into question and researched, there is minimal comparable information on opioids, the third major analgesic group. Evaluating safety levels and risks associated with any drugs should be a chief concern for both physicians and patients before any medication use begins. Attempting to better define potential risks, a study was conducted that used propensity score methods and investigated the comparative safety of the three most common types of analgesics: NSNSAIDs, coxibs and opioids.

Vast pool turns out massive sample size for efficient data
The study group consisted of eligible older adults who had been diagnosed with osteoarthritis or rheumatoid arthritis on two separate occasions, with their second trial with an analgesic prescription serving as their commencement in the cohort. Potential subjects were excluded if they used any other analgesic in the 180 days leading up to their personal start date, if they were using two simultaneously, or if they were diagnosed with malignant neoplasm or in hospice in the past year. An initial group of 163,714 potentially eligible subjects was condensed to 12,840 after applying the exclusion criteria. Researchers subsequently balanced exposure groups using propensity score matching, which is the estimated probability of receiving one treatment exposure versus another. Safety events were subsequently analyzed and categorized according to type and other pertinent information on exposures and outcomes was also recorded.

NSNSAIDs proven to be much safer than opioids
Overall, baseline characteristics of the three propensity score-matched cohorts were similar. After compiling data, it was shown that opioids produced the highest risk across most specific and severe safety events and NSNSAIDs the lowest risk. Among notable findings, the number of acute care hospital days, risk of fractures, risk of cardiovascular events, risk of safety events requiring hospitalization and risk of all-cause mortality were all higher among opioid users than other groups. Coxibs showed a few elevated risks compared to NSNSAIDs, but were not nearly as great as opioids, and when rofecoxib and valdecoxib (both taken off the market) were removed from the analysis, a number of risks decreased. Based on these outcomes, it seems evident that while NSNSAIDs naturally pose some risks of their own, they’re proven to be much safer than opioids, and comparatively safer than coxibs as well. Concerns regarding opioids should therefore continue to be raised, along with more research on their risks, and physicians should take this as proof to favor the use of NSNSAIDs over other analgesics.

-Summarized by Greg Gargiulo

-As reported in the Dec. ’10 issue of the Archives of Internal Medicine