Life without COX 2 inhibitors

Editor—In their editorial on life without COX 2 inhibitors Shaughnessy and Gordon give examples of drug and non-drug measures shown to be effective in osteoarthritis, but their discussion of opioids was not referenced.¹ The omission of studies supporting the use of opioids was surprising, particularly when references for the non-drug measures were included even when the effect sizes were small or the data limited by small numbers.

Two systematic reviews of opioids in chronic non-cancer pain report several papers showing efficacy of opioids (morphine and oxycodone) in osteoarthritis, with an average reduction in pain intensity of 30%, generally considered to be clinically meaningful.²,³ While Kalso et al note the worries of addiction and drug diversion (presumably the reason they are referred to as “a last pharmacological resort” by Shaughnessy and Gordon) and caution that not all patients respond to opioids, Kalso noted in a BMJ editorial in 2005 that the British Pain Society has published recommendations for the appropriate use of opioids in persistent non-cancer pain. The guidelines offer a framework for the safe prescribing of opioids in conditions such as osteoarthritis.⁴ A recent paper highlighted that a quarter of general practitioners sampled did not prescribe opioids for patients with persistent chronic pain, and that prescription patterns were influenced by the doctor's beliefs about the appropriateness of opioids in chronic pain, in spite of these guidelines.⁵

We are conducting a trial focusing on the acceptability to patients of opioids for osteoarthritis pain. In addition, one of us (CR) has recently completed a qualitative study examining the views of patients with cancer pain when offered morphine. Interestingly, the phrase most commonly used by them was “last resort,” which meant that they delayed the use of drugs such as morphine for as long as possible, suffering from uncontrolled pain as a consequence. Given the prejudice of this editorial, perhaps we should not have been surprised that some of these patients seemed to be reflecting the views of their doctors.