Use of strong opioids for chronic non-cancer pain: a retrospective analysis at a pain centre in Singapore

Abstract

The use of opioids in chronic non-cancer pain (CNCP) is controversial, as it presents both benefits and risks. There is currently no available data on the incidence, prescription pattern, functional outcomes and adverse effects of opioids in patients with CNCP in Singapore. This study aimed to address the aforementioned deficit. All records of patients who were prescribed strong opioids (for > 3 months per year) for the management of CNCP over a two-year period were retrospectively analysed. Factors including type of opioid, indications for opioid prescription, uncontrolled side effects, functional status, coexisting psychological issues and suspicion of aberrant drug-seeking behaviour were studied. Out of the 1,389 new patients who visited the centre, 42 (3.0%) with CNCP received strong opioids for more than three months a year. The most commonly prescribed opioid was methadone (42.9%). The principal diagnosis for opioid prescription was spinal pain (38.1%). Ten patients had severe side effects. 15 patients saw improvement in activities of daily living scores. Although ten patients returned to work, one stopped following the commencement of opioids. Aberrancy was seen in 5 (11.9%) patients, while 19 (45.2%) had psychological issues and 10 (23.8%) required psychiatric co-management. Opioids are not a panacea for chronic pain. Therefore, functional outcomes should be considered more important end points than mere reductions in pain scores. A multidisciplinary team approach is essential for the effective management of patients with CNCP who are on opioids.