Opioids for pain management in palliative care
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Opioids for pain management in palliative care
Palliative care services in the UK provide care for around 170,000 patients each year who have advanced diseases, and about 80% of these patients have cancer Pain remains the most feared symptom in advanced disease, and is frequently the most experienced symptom. For example, up to 75% of patients with advanced cancer report pain and similarly high prevalence figures exist in other advanced diseases. Sadly, under-treatment of pain persists with one recent review estimating that around one third of cancer patients do not receive appropriately strong analgesia.
Pain in advanced disease may be related to the disease itself (eg, cancer), disease treatment (eg, surgery, or osteoporotic collapse from chronic steroid therapy in respiratory disease) or from co-morbid conditions and debility (eg, post-herpetic neuralgia, leg ulcers). Within each of these aetiologies, pain mechanisms may be nociceptive, neuropathic or most commonly a mix of both. Patients with advanced disease commonly experience psychological distress which impacts on pain perception, pain tolerance and response to analgesia. While opioids are often the mainstay of analgesic management, they are seldom effective for all pains and can have significant adverse effects in unskilled hands. One review estimated that the NNT* is 2 for both morphine and oxycodone in cancer pain. Other drug and non-drug approaches should therefore be combined with opioids to improve pain outcomes.
When starting opioids and initiating safe and effective titration and maintenance treatment, refer to NICE guidance on opioids in palliative care (this provides advice on addressing patient concerns). Constipation is common and most patients will require a regular laxative. Initial nausea and drowsiness are also common but often subside within a few days without the need for additional management. If they persist, then consider reducing the opioid dose or switching opioid. Although legitimate concerns exist regarding the use of long term opioids, the problem of prolonged use may be less prominent as studies in cancer patients suggest that fewer than half of all cancer patients receive a strong opioid before their death and in those that do, median duration of treatment is approximately 11 weeks.
*NNT (number needed to treat). The number of patients needed to be treated for one to benefit compared with a control. A treatment that works for everyone, and where no patient has a response with control, would have a NNT of 1. The higher the NNT, the less effective the treatment.
Further Reading
- Bennett MI, Rayment C, Hjermstad M, et al. . Prevalence and aetiology of neuropathic pain in cancer patients: a systematic review. Pain 2012;153:359-365.
- Breivik H, Cherny N, Collett B, et al. Cancer-related pain: a pan-European survey of prevalence, treatment, and patient attitudes.Annals of Oncology 2009; 20: 1420-33.
- Greco MT, Roberto A, Corli O, et al. Quality of cancer pain management: an update of a systematic review of undertreatment of patients with cancer. Journal of Clinical Oncology. 2014; 32: 4149-54.
- Kane C, Hoskin P, Bennett MI. Cancer Induced Bone Pain (Clinical Review). BMJ 2015; 350: h315
- National Council for Palliative Care. Commissioning Guidance for Specialist Palliative Care: Helping to deliver commissioning objectives. 2012.
- National Institute for Health and Care Excellence. Clinical Guideline 140 Palliative care for adults: strong opioids for pain relief. 2012
- Solano JP, Gomes B, Higginson IJ. A comparison of symptom prevalence in far advanced cancer, AIDS, heart disease, chronic obstructive pulmonary disease and renal disease. Journal of Pain and Symptom Management 2006;31:58-69.
- Treede RD, Rief W, Barke A, et al. A classification of chronic pain for ICD-11. Pain 2015; 156: 1003-1007.
- van den Beuken-van Everdingen MHJ, de Rijke JM, Kessels AG, et al. Prevalence of pain in patients with cancer: a systematic review of the past 40 years. Annals of Oncology 2007; 18: 1437-49.
- Gao W, Gulliford M, Bennett MI, et al. Managing cancer pain at the end of life with multiple strong opioids: a population-based retrospective cohort study in primary care. PLoS One 2014; 9: e79266.