Pharmacological management of cancer pain in the elderly.

Existing studies indicate a high prevalence rate and poor management of cancer pain in the elderly. Pain is often considered an expected concomitant of aging, and older patients are considered more sensitive to opioids. Despite the well known pharmacokinetic changes in the elderly, the complex network of factors involved in the opioid response make the evaluation of a single element, such as age, more difficult. Notwithstanding such difficulties, appropriate analgesic treatment is able to control cancer pain in the elderly in most cases. Skills necessary to optimise pain control in older cancer patients include the ability to objectively assess functional age (not necessarily related to chronological age since the rate of decline is variable), understand the impact of coexisting conditions, carefully manage the numbers and types of drugs taken at the same time and adequately communicate with patients and relatives. The most common treatment of cancer pain consists of the use of regularly given oral analgesics. The elderly are at increased risk of developing toxicity from NSAIDs, and the overall safety of these drugs in frail elderly patients should be considered. When older patients have clear contraindications to NSAIDs, manifest signs of toxicity from these agents, or find that pain is no longer controlled with this class of drugs, opioids should be started. A variety of opioids are available, and they differ widely with respect to analgesic potency and adverse effects among the elderly. Although the aged population requires lower doses of opioids, only careful titration based on individual response can ensure the appropriate response to clinical demand. Elderly patients are potentially more likely to be affected by opioid toxicity because of the physiological changes associated with aging. Nevertheless, appropriate dosage and administration may limit these risks. Cancer patients with pain who do not respond to increasing doses of opioids because they develop adverse effects before achieving acceptable analgesia may be switched to alternative opioids. Despite the favourable effects reported with opioid switching, monitoring is crucial, particularly in the elderly or patients who are switched from high doses of opioids. Adjuvant analgesics, including antidepressants, antiepileptics, corticosteroids and bisphosphonates may help in the treatment of certain types of chronic pain. With an appropriate and careful approach, it should be possible to reduce or eliminate unrelieved cancer pain in most elderly patients and, consequently, to enhance their quality of life. Older patients with cancer should be continuously assessed for cancer pain, both before and after analgesic treatment.