Abstract
The elderly are often untreated or undertreated for pain. Barriers to effective management include challenges to proper assessment of pain; underreporting by patients; atypical manifestations of pain in the elderly; a need for increased appreciation of the pharmacokinetic and pharmacodynamic changes of aging; and misconceptions about tolerance and addiction to opioids. Physicians can provide appropriate analgesia in geriatric patients by understanding different types of pain (nociceptive and neuropathic), and correctly using nonopioid, opioid, and adjuvant medications.
Opioids have become more widely accepted for treating older adults who have persistent pain, but such use requires physicians have an understanding of prevention and management of side effects, opioid titration and withdrawal, and careful monitoring. Placebo use is unwarranted and unethical. Nonpharmacologic approaches to pain management are essential and include osteopathic manipulative treatment, cognitive behavioral therapy, exercise, and spiritual interventions. The holistic and interdisciplinary approach of osteopathic medicine offers an approach that can optimize effective pain management in older adults.
Pain is a common complaint of the elderly. As the number of individuals older than 65 years continues to rise, frailty and chronic diseases associated with pain will likely increase. Therefore, primary care physicians will face a significant challenge in pain management in older adults. The elderly are more likely to have arthritis, bone and joint disorders, cancer, and other chronic disorders associated with pain.
1 Between 25% and 50% of community-dwelling elderly have important pain problems.
2 Geriatric nursing home residents have an even higher prevalence of pain, which is estimated to be between 45% and 80%.
3
The elderly are often either untreated or undertreated for pain. Consequences of undertreatment for pain can have a negative impact on the health and quality of life of the elderly, resulting in depression, anxiety, social isolation, cognitive impairment, immobility, and sleep disturbances.
4 Reasons that physicians often cite for inadequate pain control include lack of training, inappropriate pain assessment, and reluctance to prescribe opioids.
2
As with other age groups, the elderly have pain that can be classified pathophysiologically as either nociceptive or neuropathic in origin. Alternatively, pain may be mixed, that is, having origins that are both nociceptive and neuropathic. Nociceptive pain may be either visceral or somatic and is due to stimulation of pain receptors. In the elderly, this stimulation may be the result of inflammation or musculoskeletal or ischemic disorders. Patients with nociceptive pain are treated pharmacologically with both opioid and nonopioid agents as well as nonpharmacologic interventions.
1,3 Neuropathic pain results from a pathophysiologic disturbance of either the peripheral or the central nervous system. In the elderly, common examples include postherpetic neuralgia and diabetic neuropathy. Patients with neuropathic pain are less likely to respond to agents used to treat patients with nociceptive pain such as pain due to bone metastasis, and more likely to respond to adjuvant agents such as anti-convulsants and antidepressants. Pain of mixed origins may respond to administration of agents that treat for both nociceptive and neuropathic pain.
1,4
Because diseases often have an atypical presentation in the elderly, it has been speculated that pain perception may be different in older adults. Although pain sensitivity and tolerance across all ages varies,
5 it is generally accepted that such differences probably do not have a significant clinical impact.
As is the case in the use of any medications in the elderly, older adults are likely to have an increased risk of adverse reactions from pharmacologic agents administered for analgesia. This propensity is likely due to pharmacokinetic changes such as reduced renal excretion and hepatic metabolism, as well as pharmacodynamic changes that occur with age, such as an increased sensitivity to certain analgesics, particularly the opioids.
2,4 In addition, polypharmacy is a contributing factor for the increased incidence of adverse drug reactions.
For pain management to be effective in the elderly, physicians need to be skillful in pain assessment; capable of recognizing the importance of a holistic, interdisciplinary team approach to care; and knowledgeable of both pharmacologic and nonpharmacologic approaches to providing optimal analgesia.
1,4
Effective assessment of pain in the elderly can be challenging. It requires an appreciation that such discomfort may present atypically, particularly in the cognitively impaired. Because biologic markers are not available, self-reporting is viewed as the best evidence for the presence of pain and the optimal way to assess pain intensity.
4 Pain has been described as the “fifth vital sign,” and therefore, physicians should regularly inquire about the presence of pain in their elderly patients. Pain can be assessed, even in those with dementia, using simple questions and screening tools.
6
Assessing pain in the elderly is often associated with significant obstacles. Older adults frequently fail to report pain because they may view that it is an expected part of old age or because they are fearful that it may lead to more diagnostic testing or added medication.
1 Some patients may accept pain as punishment for past actions.
3 Rather than admitting to the presence of pain, the elderly may use terms such as “aching” or “hurting.”
7 Communication and cognitive disturbances are additional barriers to such assessment. Increased agitation, changes in functional status, altered gait, and social isolation may be signs of pain in patients with dementia.
6
A comprehensive assessment should include a careful history and physical examination and diagnostic studies aimed at identifying the precise etiology of pain. Characteristics such as intensity, frequency, and location should be described. Standardized geriatric assessment tools to assess function, gait, affect, and cognition should be used.
8 Intensity should be assessed by using one of several pain scales that have been accepted for use in the elderly (
Figure 1).
A verbally administered 0-through-10 scale is an effective measurement of pain intensity in most older adults. When using this scale, physicians can ask patients, “On a scale of zero to 10, with zero meaning no pain and 10 meaning the worst pain possible, how much pain do you have now?” Some older adults, particularly those with dementia, may have difficulty using this scale. Other tools such as a visual analog scale, numerical scale, pain thermometer scale, and pain faces scale can be helpful.
1,4,9 Recently, evidence has established the reliability and validity for the use of the faces pain scale with older adults.
10
When possible, use of an interdisciplinary team approach to assessment and management of pain in the elderly is advantageous. These strategies need to be sensitive to cultural and ethnic issues, as well as to values and beliefs of patients and their families. Once etiologic factors are determined and therapy is initiated, a pain log or diary is appropriate to assess effectiveness of treatment. Physicians should encourage patients to record such documentation on a daily basis. Regular reassessment by use of previously administered assessment scales is important and serves to modify therapy to assure an optimal response. Reassessment should include an evaluation of compliance and the presence of adverse drug effects
11 (
Figure 2).
Even though adverse drug reactions in the elderly are a significant risk, pharmacologic intervention for pain management is the principal treatment modality for pain. Along with considering age-associated changes of pharmacokinetics and pharmacodynamics, physicians must consider the likelihood of drug-drug and drug-disease interactions. Despite these challenges, pain in the elderly can be controlled but most likely will require trials of various agents and careful titration of dosages. Because older patients may have increased sensitivity to analgesic medications, lesser dosages may be effective as compared with effective dosages in younger patients.
12 This difference is especially true when using opioid analgesics.
Inasmuch as there is still a paucity of clinical trials that focus specifically on geriatric patients, information regarding initial and titrating medication dosages may not be available. Therefore, initial doses should be lower and titration should be slower in the elderly. In addition, the general approach should be to start with nonopioid medications for treating patients with mild pain, advancing to opioids for those with moderate to severe pain. The selection of the agent should be determined by targeting the underlying pathophysiology if possible. For example, if pain is due primarily to inflammation, an anti-inflammatory agent should be given. However, if pain is predominantly neuropathic, an anticonvulsant should be used. At times, combinations of analgesics may be required.
Selecting an agent likely to cause the fewest side effects is paramount. Once dosing is initiated, it is essential that primary care physicians regularly and carefully monitor for drug side effects and adverse events.
1,4 The use of placebos is unethical, and placebos should not be used in pain management,
13 a position that the American Osteopathic Association (AOA) endorses in the statement prepared by the AOA's End-of-Life Care Committee,
14 now the Council on Palliative Care Issues. (See pages ES35-ES38.)
Most mild or moderate pain in the elderly is of musculoskeletal origin and responds well to acetaminophen given around-the-clock. This agent is well tolerated in older patients provided that both renal and hepatic functions are normal.
15 The daily dose of acetaminophen should not exceed 2 gm. Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs), because of their association with gastrointestinal bleeding and renal dysfunction, places the elderly at significant clinical risk. Although the likelihood of bleeding is lower with the concomitant use of misoprostol or a proton pump inhibitor, misoprostol is not well tolerated in the elderly. For this reason, a proton pump inhibitor may be an optimal choice.
16,17
Because of their association with a lower incidence of gastrointestinal bleeding, selective cyclooxygenase-2 (COX-2) inhibitors (coxibs) have been viewed as a safer alternative to the other NSAIDs; however, concern about their association with heart disease and stroke has dampened their acceptance and resulted in the withdrawal of rofecoxib (Vioxx) from the market.
17 Prolonged use of NSAIDs in the elderly should be avoided whenever possible.
Administration of opioid analgesics to manage chronic noncancer pain in the elderly has become acceptable; these agents are effective in treating patients with moderate to severe nociceptive pain. True addiction in the elderly is uncommon, and the possibility of addiction should not be used as justification for undertreatment of the elderly for pain.
1,18,19
Morphine sulfate and oxycodone hydrochloride, now available in both short-acting and sustained-release preparations, are commonly used. Short-acting opioids can be used in treatment of patients with intermittent pain, whereas sustained-release opioids should be given for continuous pain (with short-acting preparations available for breakthrough pain). The dosage of sustained-release opioids can be titrated based on the frequency of use of the short-acting preparation. For patients who may not be able to take oral preparations periodically, opioids are available as parenteral, sublingual, suppository (oxymorphone hydrochloride), and transdermal (eg, fentanyl patch) products.
20
Physicians should anticipate, prevent, and manage side effects. They should initiate prevention of constipation through the use of stool softeners and other prophylactic bowel regimens whenever opioid therapy is used in the elderly. When opioid therapy is initiated, sedation and delirium are commonplace until tolerance develops. Although respiratory depression occurs uncommonly, tolerance develops rapidly. If needed, naloxone hydrochloride could be used for profound respiratory depression and sedation; care must be taken when reversing this adverse effect since an antagonist action that is too powerful could propel the patient on long-term opioid therapy into withdrawal. It is advisable that patients take a maintenance dose for several days before they resume driving.
Antiemetics such as prochlorperazine or metoclopramide may be needed early on with the initiation of opioid therapy. Falls, dizziness, and gait disturbances are not uncommon; therefore, preventive precautions are often recommended, such as the use of an assistive device. Eventually, for most patients, the analgesic effect of opioids is preserved while tolerance develops to most side effects (eg, respiratory depression, sedation, nausea, and vomiting).
1,4,11,21 However, because tolerance does not develop to gastric hypomotility, patients need to take stool softeners for as long as they are on opioid therapy. Chewing or crushing sustained-release opioids must be avoided as doing so can cause rapid absorption of the entire dose resulting in overdosing.
1
Certain opioids should be avoided in elderly patients when possible. Propoxyphene is thought to be no more effective than aspirin or acetaminophen, but it is associated with ataxia, dizziness, and neuroexcitatory effects due to drug accumulation.
22 Meperidine hydrochloride should not be used because of the accumulation of a nephrotoxic metabolite. Methadone hydrochloride should also be avoided in the elderly because it has a long and variable half-life, which makes titration difficult. In addition, the analgesic action is shorter than that of respiratory depression
1 so patients whose methadone dosage is too low may increase their daily amount, which increases the risk of death from respiratory depression.
Transdermal fentanyl, contraindicated in opioid-naïve patients, should also be used with extreme caution in the elderly. It has a variable absorption rate in older adults and a long residual effect even when the patch is removed.
Tramadol hydrochloride, an analgesic that has some opioid properties and is used for mild to moderate pain, should be used with caution in the elderly because it may cause dizziness and reduce the seizure threshold.
23
Adjuvant medications are frequently used to treat elderly patients with chronic pain disorders. Many were developed for purposes other than analgesic use but have been shown to be effective in the management of certain pain syndromes.
24 Anticonvulsants, steroids, topical local anesthetics, and antidepressants are such agents that may be used alone or in combination with nonopioid or opioid analgesics.
Adjuvant medications are particularly useful in managing neuropathic pain.
4 Although tricyclic antidepressants such as amitriptyline hydrochloride and nortriptyline hydrochloride have been used to treat patients with this disorder, anticonvulsants such as gabapentin and carbamazepine are thought to be more effective.
25 In addition, amitriptyline has significant anticholinergic effects that can be problematic for geriatric patients. Gabapentin seems to be more effective and better tolerated in older adults. However, the recently available anticonvulsant pregabalin is effective and easier to tolerate than gabapentin.
26
Selective serotonin-reuptake inhibitor (SSRI) drugs are effective and well tolerated when used for treating patients with depression, but their efficacy in pain management is not documented.
1 More recently,however, serotonin norepinephrine-reuptake inhibitor (SNRI) in duloxetine, has been shown to be effective for the treatment of patients with neuropathic pain and seems to be well tolerated in the elderly.
27
When selecting an adjuvant agent to treat the elderly for pain, physicians should: (1) prescribe medications with the lowest side effect profile for older adults; (2) titrate the drug slowly; and (3) assess patients carefully for both effectiveness and the presence of adverse effects
1,2,4 (
Figure 3).
Although most elderly patients require pharmacologic intervention to manage pain, nonpharmacologic approaches may have an added benefit and should be routinely considered. This aspect is particularly important in older adults because procedures that avoid drugs have a low frequency of adverse reactions compared with pharmacologic approaches.
Although many nonpharmacologic methods lack rigorous, evidence-based studies to document their efficacy, the body of knowledge to substantiate their use is increasing, particularly when such methods are used in conjunction with drug therapy.
15,28,29
Patient and caregiver education is essential as a mechanism to improve pain management in the elderly. Patient education programs typically include information about the nature of pain, assessment instruments, medication use, and nonpharmacologic treatment modalities, as well as coping strategies. Both one-on-one as well as group programs can be effective. Caregiver education is especially important in caring for the elderly.
28,29
Cognitive-behavioral therapy using a structured systemic approach to teaching coping skills has been shown to be effective. It requires a trained therapist conducting 6 to 10 sessions.
1,30
Clearly, osteopathic manipulative treatment is effective in the management of chronic pain.
31,32 The type of techniques and the extent of intervention must be tailored to the individual.
4 The holistic approach to care, central to the practice of osteopathic medicine, supports the need for an interdisciplinary team approach to the care of elderly patients with chronic pain.
31-33
Evidence exists that participation in regular physical activity can reduce pain and enhance functional capacity of older adults with persistent pain.
34 Additionally, an assessment by a physiatrist, physical therapist, or occupational therapist may be helpful for recommending ways to improve muscle strength and avoid dysfunction and also for identifying the appropriate use of heat, cold, or massage therapy. Both acupuncture and transcutaneous electrical nerve stimulation have been used with modest success for management of persistent pain in older adults.
4
Last, for many patients, there exists a spiritual dimension to persistent pain; evidence exists to support spirituality as being helpful to some who are suffering from persistent pain.
35 Keeping in mind the basic osteopathic tenet, “A person is the product of dynamic interaction between body, mind, and spirit,” appropriate counseling or referral to clergy may be helpful in the management of pain
4 (
Figure 4).
Primary care physicians often are confronted by elderly patients such as the one in the following case scenario, which is representive of problems in pain assessment and treatment decisions.
Mrs Jones, an 80-year-old woman, has a history of Alzheimer disease in the middle stages and metastatic breast carcinoma to bone. She has resided in a nursing home for the past year. Lately, she has had increased agitation and confusion. She was recently treated with haloperidol because of the confusion; this medication did not improve her mental status. Upon questioning, she complained of pain and pointed to her back and left leg. Mrs Jones had been treated with opioid analgesics initially as needed, then around-the-clock, without any improvement. Her current medications include aspirin, 81 mg/d; donepezil hydrochloride,10 mg/d, haloperidol, 0.5 mg twice a day; and memantine hydrochloride, 10 mg twice a day.
An attempt to reintroduce long-acting opioids after careful titration resulted in only minimal improvement in this patient's pain. Therefore, pregabalin was added because of the neuropathic origin of the pain. This addition was supported by the nature of the pain and the lack of pain relief through the reintroduction of long-acting opioids.
The elderly are frequently untreated or undertreated for pain because of barriers to recognition, assessment, and management in such patients. A greater understanding of clinical manifestations of pain, improved methods of assessment, and use of both pharmacologic and nonpharmacologic interventions can result in more favorable outcomes in the treatment of older adults for pain. Osteopathic physicians are uniquely equipped for optimal care of elderly patients with persistent pain by incorporating benefits of manipulative treatment and using holistic and team approaches of osteopathic medicine (
Figure 5).