Pain in the elderly with cancer

    Today, one fourth of the world population in the West is over age 70. Over the next two decades, that proportion will rise to one-third. As the population ages, the incidence of malignant tumors also rises, not only because there is more time for cancer to develop but also because older tissues may be more susceptible to environmental carcinogens.1 The typical patient with cancer is approximately 60 years old, with multiple medical problems, taking several medications simultaneously, and his or her caretaker is often older than 60.2 In addition, half of the patients with cancer experience moderate to severe pain at the time of diagnosis and at least 80 percent of elderly patients will have significant pain when cancer is advanced.3

The challenges of caring for elderly patients
    The care of elderly patients is more complex than that of younger patients.4 Often elderly patients do not present with typical signs and symptoms of disease; this makes timely and accurate diagnosis more difficult. The elderly take more drugs than younger patients and this places them at increased risk for drug-drug and drug-disease interactions.5

    According to Dr. Cori Schroder, a geriatrician from Ontario, Canada, older patients are much more reluctant to make decisions about their own care than middle- aged patients. Older patients like to rely on their families for such decisions. A common challenge for clinicians is dealing with families who do not know how to make decisions affecting the medical care of their parents.

Tailoring pain assessment to the elderly
    Some data suggest that elderly patients traditionally underreport their pain.6 Many do so, because they assume that pain is a normal part of aging. Others are trying to be good patients and they believe that good patients do not complain. Elderly patients with cancer may be unwilling to report pain because of fear that reporting pain will take physician time away from the treatment of their cancer, or because they fear that worsening pain means progression of disease.

    This is why it is critical to assess and reassess pain in elderly patients, according to Dr. Christine Miaskowski, of the University of California in San Francisco. The clinician also needs to consider other pre-existing or concomitant painful conditions common in this age group, she said, such as arthritis, osteoporosis, or fractures as a result of falls.

    Pain assessment tools should be tailored to meet the unique characteristics and needs of the elderly patient. Clinicians can use a simple tool, such as happy/sad faces and have the family use the same tool at home to record the patient's pain. This makes it easier to track pain over time, and monitor improvement or deterioration.

    Because elderly patients often react more slowly, clinicians should allow ample time to perform the assessment. Moreover, the high incidence of visual, hearing and motor impairments may interfere with the patient's self-report. Therefore, assessing pain in an environment that is quiet, free of distractions and with adequate lighting is helpful.

    If the patient is unable to communicate verbally, caregivers can have the patient write information out or point to enlarged words, numerical scales, or anatomical drawings to identify pain. If the patient is unable to communicate at all, asking for the family's input and looking at the patient's behavioral cues must become part of the assessment.

    "You may ask a patient how their pain is today compared to yesterday, but some cannot remember what happened 10 minutes ago" said Dr. Schroder. "So you must simply accept the patient's report of pain at each point in time." In this case and when memory disturbances or changes in cognition complicate the assessment of pain in an elderly patient, it is helpful to rely on a family member or caregiver to provide a recent pain history.

Pain assessment in the cognitively impaired elderly
    Cognitively impaired patients require tools different from other patients because their behavior is different, said Dr. Schroder. Instead of complaining about pain, cognitively impaired patients may become quiet when they have pain. So it is important for clinicians to pay attention to changes in the patient's behavior that signal pain.

    A behavioral scale has been developed by a team of French and Swiss geriatricians to assess pain among elderly non-verbal patients or patients with cognitive impairment. The DOLOPLUS scale uses somatic, psychomotor and psychosocial reactions of the patient to diagnose pain severity.7 As a rule, cognitively impaired patients require simpler scales and more frequent assessments.

Treating cancer pain in the elderly
    Elderly patients are often undertreated for cancer pain.

    In a study of 1308 outpatients with metastatic cancer being followed by oncologists, 796 patients reported experiencing pain and 475 (62%) described it as being substantial. Older patients were more likely than younger patients to report inadequate pain management.8    A study of elderly nursing home residents with cancer showed that daily pain is widespread and often untreated, especially among older and minority patients.9 In that study, 1 in 4 patients with cancer in a nursing home did not receive any analgesia for daily pain. The study examined data collected on 13,625 cancer patients aged 65 and older discharged from hospitals to nursing homes from 1992 to 1995. In total, 4,003 patients reported daily pain. Of those, 16 percent received a simple analgesic such as aspirin or acetaminophen. Thirty-two percent were given codeine or other weak opioids, and 26 percent received morphine. However, 26 percent of patients with daily pain received no analgesics, not even an aspirin or acetaminophen tablet. Patients older than 85 years in daily pain were about 50 percent less likely to receive any analgesic than those  aged 65 to 74 years. Only 13 percent of patients aged 85 years and older received codeine or other weak opioids or morphine, compared to  38 percent of those aged 65 to 74 years.

    This study suggests that many frail and older cancer patients receive inadequate medical treatment and that dramatic room exists for improving how pain is managed in these individuals.

    In fact elderly patients, like other adults, require aggressive pain assessment and management. Non-opioid analgesics, including acetaminophen and other NSAIDs are helpful adjuncts to opioids for cancer-related pain. Because NSAIDs are more likely to cause gastric and renal toxicity and other drug reactions in older patients, alternative NSAIDs (e.g. choline magnesium trisalicylate) should be considered to reduce gastric toxicity.5

Opioid use in the older cancer patient
    Opioids are effective for moderate to severe cancer pain in the elderly and they have no analgesic ceiling. Because aging changes how the body metabolizes and eliminates drugs, opioids remain in the body longer and at higher concentrations, so their effects are greater and last longer in the elderly than in younger patients. Because of the longer duration of pain relief with opioids, it is best to start with low doses of opioids in the elderly and to go slow, said Dr. Miaskowski. The literature suggests beginning with one-half or one-third of the normal adult dose.5 It is important to titrate doses to achieve maximal analgesia without side effect and to monitor both renal and hepatic function, which are critical parameters in the elderly population.

    "Because the effects of morphine are the best understood and the most predictable, morphine is the standard with which other opioids should be compared in elderly patients," said Dr. Bruce Ferrell, of the University of California at Los Angeles.

    Hydromorphone, an analgesic with a shorter duration of action, is an alternative to morphine for the elderly, with similar analgesia and side effects.10

   As a rule, the preferred analgesics for elderly patients are those with the lowest side-effect profiles. The reluctance by physicians to prescribe opioid analgesics to older cancer patients has been attributed to fear of adverse effects.

Treatment of opioid-induced side effects in the elderly
    In fact, opioid side effects are potentially greater in the elderly because of the changes in the distribution and in the excretion of drugs in that population.9 In addition, the medications used to treat side effects can cause side effects themselves.

    The most effective strategy to manage any opioid-induced side effect is to decrease the dose of the opioid causing the side effect.10   If the patient has satisfactory pain relief, the opioid dose can be decreased by 25% to 50%, depending on the severity of the side effect.

    Constipation is very common in most elderly patients. Starting opioid therapy will make it worse. Tolerance to the constipating effect of opioids occurs very slowly, if at all, during chronic therapy. In fact, it may worsen with time because of disease complications (e.g., development of intestinal obstruction). Unless contraindicated, all patients should increase fiber consumption.11

    Sedation is also a common problem in the elderly cancer patient, especially when opioid doses are increased substantially. However, tolerance generally develops rapidly. If tolerance does not develop, persistent drug-induced sedation may be treated by reducing the opioid dose and increasing the frequency of administration. This will decrease peak concentrations in the blood and brain while maintaining the same total dose. If this approach is unsuccessful, the patient may need to take central nervous system stimulants (e.g., caffeine, dextroamphetamine, pemoline, methylphenidate) to increase alertness.11

    Respiratory depression is feared when opioids are administred to the elderly for pain control. As with other side effects, tolerance usually develops over time. However, respiratory depression occasionally occurs when an opioid abruptly relieves pain and the stimulating effect of the pain no longer counteracts the sedating effect of the opioid, resulting in hypoventilation. Respiratory depression occurs rarely except in the opioid-naive patient and those with significant pulmonary disease.11

    Because the elderly often take multiple medications, there is always the possibility of drug interactions. It is therefore recommended to take a complete medication history before beginning analgesic treatment. Regular communication between all the caregivers of the elderly cancer patient will make the pain treatment safer and more effective.10

Non-drug pain relief
    Aside from pharmacotherapy, other approaches may be very useful in elderly patients who continue to have pain. Combining non-pharmacologic approaches with medication may allow clinicians to use lower drug doses, which is a good strategy to limit the risk of adverse effects common in the elderly.

    Research on the use of non-pharmacologic methods of pain relief among cancer patients cared for at home shows that heat and vibration are the most effective for this population.12  Cognitive-behavioral techniques focus on changing the perception of pain, and increasing the patient's sense of control over the pain. The therapist begins educating the patient about pain and the role of cognition in pain perception. The elderly patient records episodes of pain and then discusses the thoughts that accompany the episodes with his or her nurse. Relaxation methods are incorporated to divert the patient's attention from the pain. Eventually, patients develop a sense of mastery over the pain.13

Educating patients
    Educating patients to report pain can make a difference between poor pain management and better pain management in the elderly. A recent study in the Netherlands has shown that patients can be educated to report pain and to contact health care practitioners to request medication. Educated patients experienced better pain control than those who did not receive the education.14

Conclusion
    Elderly cancer patients with pain may benefit more from small amounts of many treatments (drug and non-drug) than an intense trial of a single one. It is encouraging that more clinical research has recently begun to focus on chronic pain in the elderly.

Sophie M. Colleau, PhD

References
1. According to the US National Cancer Institute, the incidence of malignant tumors is 193.9 per 100,000 for people less than 65 years old. For people over 65, the incidence is 2,085.3 per 100,000.

2. Ferrell BA. Pain evaluation and management in the nursing home. Ann Intern Med 1995; 123 (9): 681-687.

3. Ferrell BR, Ferrell BA (eds) Pain in the elderly. Seattle: IASP Press, 1996.

4. Thomas EJ, Brennan TA. Incidence and types of preventable adverse events in elderly patients: population based review of medical records. BMJ 2000; 320:741-744.

5. Jacox A, Carr DB, Payne R, et al. Management of cancer pain. Clinical Practice Guideline No. 9. AHCPR Publication No. 84-0592, 1994.

6. Ward SE, Goldberg N, Miller-McCauley V, et al. Patient-related barriers to management of cancer pain. Pain, 1993: 319-324.

7. Michel M, Capriz F, Gentry A. et al. Doloplus-2, une échelle comportementale de la douleur validée chez la personne agée. Etude de la fiabilité. [Doloplus 2: A behavioral pain scale validated for the elderly. Reliability study] La Revue de Gériatrie, 2000; 25 (3): 155-160.

8. Cleeland CS, Gonin R, Hatfield AK, Edmonson JH, et al. Pain and its treatment in outpatients with metastatic cancer. N Engl J Med 1994;330:592-596.

9. Bernabei R, Gambassi G, Lapane K, Landi F, et al. Management of pain in elderly patients with cancer. JAMA 1998; 279: 23:1877-1882.

10. McCaffery M, Pasero C. Pain: Clinical manual. Mosby: 1999: 687.

11. Dennis S, Safford CM, Eland J. Elderly pain and communication, Univ of Iowa CEU, 1999.

12. Rhiner M, Ferrell BR, Ferrell BA et al. A structured non-drug intervention program for cancer pain. Cancer Pract 1993; 1: 137-143.

13. Schmidt Luggen A. Cancer pain in the older adult. In: Handbook for the care of the older adult with cancer. Pittsburgh: Oncology Nursing Press, 2000: 107-128.

14. De Wit R, van Dam F, Zandbelt L, et al. A pain education program for chronic cancer pain patients: follow-up results from a randomized controlled trial. Pain 1997; 73: 55-69.