Analgesia for patients with advanced disease: I.(Review)(pain management in diseases like cancer)

Postgrad Med J 2004;80:148-154. doi: 10.1136/pgmj.2003.015511

This series of two articles explores the challenge of managing pain in patients with advanced malignant and non-malignant disease. Pain is a common symptom in advanced disease. Despite guidance from organisations such as the World Health Organisation, cancer pain is often inadequately managed. Managing pain in non-malignant conditions, such as end stage cardiac failure, presents an even greater challenge to healthcare professionals. This first article discusses epidemiology, definitions, pathophysiology, assessment, non-pharmacological approaches, the analgesic "ladder", and opioids. The second article will examine the use of non-opioids, anaesthetic techniques, and analgesia in dying patients as well as discussing future directions.

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Pain occurs in 40%-80% of patients with advanced progressive disease. (1 2) Despite publication of the World Health Organisation (WHO) guidelines for managing cancer pain nearly two decades ago, (3) management of pain still presents a challenge in everyday practice. Most of the available evidence for managing pain arises from studying cancer patients, but many of the basic principles can be applied to non-malignant as well as malignant disease.

EPIDEMIOLOGY

Prevalence studies have reported figures of 40%-80% for cancer pain. The prevalence rises with advancing disease and may be higher in certain types of cancer. (1) One of the challenges in managing pain is that patients may have more than one pain. For example, in a study of 200 patients presenting to a specialist cancer pain clinic, approximately 75% had multiple pains. (4) Until recently, it was widely believed that patients dying from non-malignant disease did not have high levels of pain. However, it is now known that patients dying from cardiac failure or chronic airways disease suffer similar levels of pain (2) to those found in patients with malignant disease.

DEFINITION OF PAIN