Opioids have more side effects than benefits on humans

Washington: In a recent study, researchers suggested that opioids contribute no measurable benefit to the quality of life or depression for patients suffering from osteoarthritis (OA). The study also found small benefits on pain and function after two to 12 weeks of treatment and interestingly, strong opioids had consistently worse pain relief benefits and a greater risk of any safety-related outcome.

The study was presented in the 'ACR/ARP Annual Meeting.' Osteoarthritis is a common joint disease that most often affects middle-age to elderly people. It is a disease of the entire joint, involving the cartilage, joint lining, ligaments, and bone. OA is characterised by a breakdown of cartilage tissue, bony changes of the joints, deterioration of tendons and ligaments, and various degrees of inflammation of the joint lining, also called the synovium.

Opioids, long prescribed for chronic pain, have many safety concerns. The lack of information about the drug's effectiveness for OA pain relief and no clear delineation between overall efficacy and safety between strong and weak opioids prompted the study.

"Given the current controversy regarding the use of opioids in chronic pain, we wanted to delve deeper into the efficacy and safety profiles of oral opioid drugs in osteoarthritis patients," said lead researcher Raveendhara R Bannuru.

"Temporal assessments can reveal peak periods of efficacy and can provide clinicians with a blueprint for optimal durations of treatment regimens. Our study also provides an important update to the evidence body by evaluating patient-reported outcomes of quality of life, depression, and sleep that are relevant to clinicians and patients alike."

The study included meta-analyses of pain and function at two, four, eight, and 12 weeks. It also analysed relevant safety outcomes for all opioids, as well as strong versus weak opioids. They searched MEDLINE and the Cochrane Database from inception to April 2019, and actively sought unpublished data.

Of the 23 randomised controlled trials included, there were 11,402 participants and 64 percent were female. The participants' mean age ranged from 54 to 67 years. Their mean body-mass index (BMI) ranged from 28 to 34 kg/m2. All of the trials included in the study were of moderate quality, and potential attrition bias was the primary methodological concern.

Overall, the results showed that opioids demonstrated small, statistically significant benefits on pain at each time point. Similarly, the researchers observed small, statistically significant effects on function at two, four, eight, and 12 weeks. Opioids had no impact on the quality of life or depression.

At last, the study found that strong opioids consistently had smaller benefits on pain than weak opioids. Though results of meta-regression exploring dose effects revealed a relevant relationship between opioid dosage, or morphine equivalency, and the magnitude of pain relief, participants receiving strong opioids were nearly twice as likely to discontinue due to adverse events than those receiving weak/intermediate opioids.