The elderly should be considered an at-risk group for the undertreatment of cancer pain because of inappropriate beliefs about their pain sensitivity, pain tolerance, and ability to use opioids. Elderly patients, like other adults, require aggressive pain assessment and management.
Pain management in the elderly presents several challenges, including the discrepancy between the high prevalence of pain in the elderly and the limited attention to this group in the research literature and in medical and nursing texts (Ferrell, 1991). Of all reports about pain published annually, fewer than 1 percent focus on pain experience or syndromes in the elderly (Melding, 1991). Current pharmacologic research is often limited to single-dose studies in young or middle-aged adults and does not assess the complications and side effects of medications in the elderly. Elderly patients who participate in pain clinics or studies are likely to be the mobile elderly. Furthermore, elderly patients-are often excluded from rehabilitation programs and aggressive treatment of pain (Middaugh, Levin, Kee, et al., 1988; Sorkin, Rudy, Hanlon, et al., 1990).
In spite of the lack of research, there is evidence that the elderly experience more pain than younger people. It has been estimated that the prevalence of pain in those older than 60 years of age (250 per 1,000) is double that in those younger than 60 (125 per 1,000) (Crook, Rideout, and Browne, 1984). Among the institutionalized elderly, the prevalence of pain may be over 70 percent (Ferrell, Ferrell, and Osterweil, 1990). Elderly patients with cancer often have other chronic diseases, more than one source of pain, and complex medication regimens that place them at increased risk for drug-drug as well as drug-disease interactions.
Cognitive impairment, delirium (common among the acutely ill elderly), and dementia (which occurs in as many as 50 percent of the institutionalized elderly) pose serious barriers to pain assessment (Kane, Ouslander, and Abrass, 1989). Psychometric properties of pain assessment instruments, such as VAS, verbal descriptor, and numerical scales, have not been established in this population. Moreover, a high prevalence of visual, hearing, and motor impairments in the elderly impede the use of these tools. Research on the nursing home population shows that many patients with mild to moderate cognitive impairment are able to report pain reliably at the moment or when prompted, although their pain recall may be less reliable. These findings suggest that this population may require more frequent pain assessment than patients who are not cognitively impaired (Ferrell, in press, a).
Nonopioid analgesics, including acetaminophen and other NSAIDs, are helpful adjuncts to opioids for cancer-related pain. The risk for gastric and renal toxicity from NSAIDs is increased among elderly patients, however, and unusual drug reactions including cognitive impairment, constipation, and headache are also more common (Roth, 1989). Factors that may contribute to altered side effects in the elderly include multiple medical diagnoses, multiple drug interactions, and altered pharmacokinetics. If gastric ulceration is a concern, NSAIDS with lower gastric toxicity (e.g., choline magnesium trisalicylate) should be chosen. The coadministration of misoprostol should also be considered as a way to protect the gastric mucous.
Opioids are effective for the management of cancer pain in most elderly patients. In the elderly, Cheyne-Stokes respiratory patterns are not unusual during sleep and need not prompt the discontinuation of opioid analgesia. Elderly people tend to be more sensitive to the analgesic effects of opioids, experiencing higher peak effect and longer duration of pain relief (Kaiko, 1980). The elderly, especially those who are opioid naive, also tend to be more sensitive to sedation and respiratory depression, probably as a result of alterations in metabolism and in the distribution and excretion of the drugs. For this reason, the prolonged use of longer acting drugs such as methadone requires caution (Ferrell, 1991).
Elderly people in general have increased fat-to-lean body mass ratios and reduced qlomerular filtration rates. Opioids produce cognitive and neuropsychiatric dysfunction through poorly defined mechanisms that in part include the accumulation of biologically active metabolizes such as morphine-6-glucuronide or normeperidine (Melzack, 1990). Opioid dosage titration should take into account not only analgesic effects but also side effects that extend beyond cognitive impairment. Such side effects may include urinary retention (a threat in elderly males with prostatic hypertrophy), constipation and intestinal obstruction, or respiratory depression.
Local anesthetic infusions, including lidocaine or opioids, may result in cognitive impairment if significant drug levels in the blood are reached. Orthostatic hypotension and clumsiness may result from tricyclic antidepressant administration and other medications used for pain management and concurrent medical illnesses. Precautions, such as assistance during ambulation, should be taken to prevent falls and fractures.
PCA was shown to be safe and effective for postoperative pain relief among some elderly patients (Egbert, Parks, Short, et al., 1990). PCA has not been extensively studied for long-term use in the elderly with cancer-related pain. The use of any "high-tech" pain treatment such as PCA or intraspinal analgesia should be titrated and monitored especially closely because of the elderly patient's increased sensitivity to drug effects (Ferrell, Cronin Nash, and Warfield, 1992).
Cost and Reimbursement for Pain Management
Ongoing Pain Assessment
PAIN IN SPECIAL POPULATIONS
Analgesics and Adiuvants
Analgesics for Neonates and Young Infants
Substance Abusers
Minority Populations
MONITORING THE QUALITY OF PAIN MANAGEMENT
Index