Chronic Pain in the Elderly: Special Challenges
People aged 65 years and older are the fastest-growing demographic in the United States. By 2040, they will make up about 25% of the population.1 Medical science, technology, and changes in attitudes about aging have increased the amount of time this population can expect to maintain active and productive lives.
The incidence of chronic pain will increase in older patients. The most common causes of chronic pain in this patient population include arthritis, cancer, diabetes mellitus, and cardiovascular and neurologic diseases. In addition, as we learn more about a biopsychosocial approach to pain management instead of a purely medical approach, it is important to look at changes in lifestyles as people age that also may contribute to worsening pain syndromes.
Older patients frequently are on multiple medications for concomitant medical problems, increasing the risks for side effects and even mortality from pharmacologic agents. In addition, there are some key dynamics of pharmacotherapy that need to be understood and compensated for as decisions about medication management are undertaken.2 These include the following:
- Older adults have a higher percentage of body fat and decreases in body water and muscle mass. This means that water-soluble drugs become more concentrated and have higher initial concentrations. Fat-soluble drugs have longer half-lives due to slower release from the body’s fat stores.
- The livers of older patients are frequently smaller and have less blood flow, resulting in a decrease in the number of functioning hepatocytes. This, along with medications affecting the cytochrome P450 system, leads to changes impacting drug metabolism that need to be carefully individualized for each patient.
- An increase in the incidence of renal disease impacts decisions about medications affected by renal clearance or known to increase the risk for renal damage. Even in the absence of known renal disease, renal clearance can decline significantly in older patients, impacting the adverse event profile of a number of medications used without problems in younger patients.
Despite the complexity of treating chronic pain in older individuals, the benefits of addressing and treating pain are clear. Chronic pain decreases function, increases the incidence of depression, creates kinesiophobia (fear of movement), and may worsen other chronic diseases that require ongoing management for maximal control, such as diabetes, hypertension, and heart disease.
Pain can decrease the ability of patients to focus, sleep, and cope with the common stressors of life.3 As a result, poorly treated pain not only decreases the quality of life for patients, but also increases healthcare costs significantly. Unfortunately, however, a desire for rapid, inexpensive pain relief has frequently led to an increase in potentially dangerous polypharmacy without a full use of nonpharmacologic options.
This article reviews many options for chronic pain treatment in older patients, with a focus on the use of nonpharmacologic as well as pharmacologic options to increase the chance for pain reduction with improvement in patient function.
The importance of pain assessment and reassessment cannot be overemphasized. However, finding the time to accomplish this in a typical primary care visit can sometimes be quite difficult in the context of managing many of the other problems that an older patient may have. In a recent survey of Veterans Affairs (VA) primary care providers, the following factors were listed as barriers to effective pain management in primary care: 1) inadequacies in education and training; 2) lack of consultant support; 3) psychosocial complexity; 4) time pressures; 5) skepticism; and 6) systems limitations.4 This is echoed in non-VA primary care settings as well.
Setting up a separate time to review pain-related problems or getting help from other members of the primary care team may be necessary to effectively manage pain. Getting a good history is frequently more challenging in the older patient and may be complicated by a number of factors. Many older patients think that pain is expected as they get older and something they just have to live with. In addition, even with new programs for prescription payment, many older patients on fixed incomes remain concerned about spending money for medications or medication copays.
There remain concerns on the patient’s part that complaints of pain may result in unwanted testing, a diagnosis such as cancer, or a medication regimen that may not be tolerated. In addition, patients with cognitive problems may have difficulty expressing their pain, so other clues may be necessary to determine the extent of difficulty the patient is having.
Taking a Careful History
There are many pain scales, such as a numeric rating scale or a verbal descriptor scale, that may be helpful, but in many patients other cues may be necessary. These can include changes in behavior, decreases in activity level, facial grimacing, or gait changes. Each pain history should include provocative or palliative features of the pain, quality of the pain, whether the pain radiates, the severity of the pain in terms of ability to function, and the timing of the pain both in terms of total length of pain as well as times of the day that the pain is better or worse. In addition, mental health concerns, such as depression or anxiety as well as substance abuse problems, not only exacerbate an underlying pain problem but also impact treatment decisions. These underlying comorbidities may not be easily diagnosable with simple lab tests, and a history geared toward these diagnoses should also be included.
A physical examination focused on areas of pain is important. However, examination of lungs, heart, and abdomen as well as a neurologic exam may be equally important in determining the best approach to diagnostic and treatment options.
Further laboratory diagnostic studies to be considered include vitamin D levels, screening for appropriate inflammatory rheumatologic disorders, complete blood count, metabolic profile, and thyroid function testing. There are some studies that indicate significant vitamin D deficiency can make pain worse.5 At a minimum, vitamin D replacement in deficient individuals can help with osteoporosis prevention and decrease the risk for painful fractures in the future.6
X-rays of the painful areas to assess pathology can be instructive for the provider as well as the patient. However, it is frequently unnecessary to do a magnetic resonance imaging of these areas unless it is felt to be important for potential intervention if conservative treatment fails. Dual-energy x-ray absorptiometry scanning is helpful in men as well as women to determine if treatment for osteoporosis is indicated.