RENEW OR SUBSCRIBE TO PPM
Subscription is FREE for qualified healthcare professionals in the US.
10 Articles in Volume 16, Issue #9
Health and Economic Benefits of Exercise Programs for Seniors
Role of Physical Activity in Managing Chronic Pain in Older Adults
Levorphanol: An Optimal Choice for Opioid Rotation
Incorporating Functional Medicine Into Chronic Pain Care
Expanded Use of EMG-NCV Helps Guide Treatment of Lower Extremity Neuromuscular Disorders
Application of Acupuncture to Treat Low Back Pain
People With Sickle Cell Trait at Greater Risk of Rhabdomyolysis
A Case of Statin Therapy in a Patient With Rhabdomyolysis
Overview of Exertional Rhabdomyolysis
Benzodiazepines and Opioids: Only Trained Pain Practitioners Should Prescribe

Role of Physical Activity in Managing Chronic Pain in Older Adults

To prevent or reduce chronic pain, clinicians should advise older adults to seek opportunities to move rather than remain sedentary in all daily activities, and to increase physical activities for optimal weight control.

The prevalence estimates of chronic pain among the elderly (>65 years) in the United States may be as high as 60% to 75%, with rates even higher for older adults in assisted living facilities or nursing homes.1,2 Epidemiological studies indicate that the prevalence of chronic pain increases with age up to the 7th decade of life and then plateaus or slightly declines.3 The most common types of pain in older adults include low back pain, joint osteoarthritis (eg, knee and shoulder), and peripheral neuropathic pain (often secondary to diabetes).4,5 Pain promotes physical disability,6,7 reduces quality of life,8 and is costly to both the individual experiencing pain and the nation.9

A recent study indicated that the national cost of pain exceeded the cost of the nation’s priority health conditions (eg, cardiovascular disease, neoplasms, endocrine, nutritional and metabolic diseases), with costs ranging from $560 billion to $635 billion annually.9 Alarmingly, more than half a billion people are currently over age 65 in the US, with this number expected to triple by 2050.10 As the number of older adults rises, frailty and chronic conditions associated with pain are likely to increase proportionally. Thus, primary care physicians (PCPs) can expect to encounter a considerable challenge in pain management with elderly patients. Given the burden of chronic pain in the elderly, possible preventive measures are both prudent and of the utmost importance.

Prescribe Physical Activity Preventively

Regular physical activity is a well-accepted approach for the management of chronic pain and is often recommended as an adjunct to pharmacotherapy. Physical activity also may play an important role in the prevention of persistent pain in older adults. Unfortunately, adults become more sedentary with advancing age, and consequently most older adults do not attain the minimum physical activity recommendations set forth by the American College of Sports Medicine (ACSM).11,12 This paper will provide a review of the current evidence for the role of physical activity in the prevention of persistent pain in the elderly as well as make a case for the role of physical activity in combatting 2 known and common risk factors—obesity and the decline of central pain modulatory processes—for chronic pain in older adults.

Current Evidence and Recommendations

While the experience of pain and physical activity appear connected bidirectionally, mounting evidence from prospective epidemiological studies suggests that a physically active lifestyle may reduce the risk of developing chronic pain in older adults.13-15 In a prospective cohort study of twins, the association between physical activity and incident low back pain (LBP), 1 of the most common forms of chronic pain in older adults in the elderly, was investigated.15 Being engaged in strenuous physical activity at baseline was strongly protective of developing LBP (either of shorter and longer duration)at the 2-year follow-up. Additionally, a relationship was found between increasing frequency of strenuous physical activity and the magnitude of the protective effect.15 Strenuous physical activity was defined as heavy gardening, long walks (>30 minutes) or bike rides, team sports, or dancing.15

A 14-year prospective longitudinal study investigated the impact of aerobic exercise on musculoskeletal pain in older adults who were Runners’ Association members and community controls.13 Runners had markedly reduced pain levels relative to controls, despite the fact that fractures were somewhat more prevalent among the runners. Additionally, exercise was associated with a substantial reduction in musculoskeletal pain even after controlling for sex, baseline body mass index (BMI), and attrition. These large prospective studies provide compelling evidence for the protective effect of regular moderate-intensity physical activity for low back pain and musculoskeletal pain in older adults.

While the direction of causality could not be inferred, several large cross-sectional epidemiological studies support the relationship between chronic pain and regular physical activity in older adults.14-16 Evidence from the Nord-Trondelag Health Study (HUNT 3), involving more than 46,000 participants, found a linear relationship between chronic pain and the frequency, duration, and intensity of recreational exercise for participants over 65 years.14 However, a U-shaped relationship between chronic pain and exercise frequency was discovered for individuals age 20 to 64 years in which inactivity and excessive activity were associated with chronic pain.15 The different chronic pain-exercise relationships found between age groups was attributed to a lower total amount of physical activity among older adults compared to middle-age and younger adults. In line with this theoretical U-shaped relationship between chronic low back pain and physical activity, Heneweer and colleagues revealed that the extremes of low and high physical activity levels were associated with an increased risk for chronic low back pain in middle-age and older adults.16 This U-shaped relationship was especially true for women but less so in men. Further evidence supports heavy  physical workloads; frequent lifting, bending, and twisting; and extreme sport activities may raise the risk for low back pain.17-19 While physical activity may act as a preventive factor for chronic pain, excessive physical activity may raise the risk for pain in some chronic pain conditions (Figure 1).16

While several large epidemiological studies offer a strong association between a physically active lifestyle that reduces the risk for the development of chronic pain, direct evidence is still lacking. Therefore, characteristics of optimal physical activity programs for the prevention of chronic pain presently are not known. As such, until high-quality evidence becomes available, older adults should be encouraged to meet the ACSM’s physical activity recommendations for older adults for the purpose of pain prevention (Table 1).20

Given the potential U-shaped relationship between physical activity and development of chronic pain, older adults should be encouraged to follow a gradual progression to moderate- versus vigorous-intensity exercise. Walking is often the most common, or primary, form of aerobic exercise recommended for older adults; however, aquatic exercises, stationary cycling, yoga, and Tai Chi are equally acceptable and potentially preferable for older adults with any physical limitation. Additionally, an abundance of practical experience supports the idea that increased muscle strength and endurance would help in the prevention of many types of pain, including neck, shoulder, and back pain. However, no evidence exists for the effectiveness of specific strengthening exercises in the prevention of chronic pain. Indeed, in a review of the role of physical activity by the international Paris Task Force on Back Pain, the expert panel found “no new good evidence for or against the use of back strengthening exercises for the primary prevention of LBP in adults.”21 Therefore, older adults should be encouraged to do resistance training in order to strengthen all major muscle groups. Resistance training may include progressive weight training or weight-bearing calisthenics, such as step-ups or chair exercises for those who require a more stationary activity method.

The Impact of Physical Activity on Chronic Pain Risk Factors

Strong indirect evidence also suggests that regular physical activity may be an effective strategy to reduce the risk for chronic pain in older adults. Specifically, regular physical activity can beneficially impact several well-known risk factors for chronic pain that commonly occur with age, including obesity and central pain modulatory processes. Both obesity and dysfunction of central pain processes predispose aging adults to chronic pain of many different origins. A review of the value that physical activity can have on these risk factors and the implications for chronic pain is discussed below.

Obesity

Recent estimates indicate that over two-thirds of older adults are overweight and one-third of older adults are obese.22 Substantial evidence suggests that obesity is 1 of the most influential risk factors for osteoarthritic (OA) knee pain and chronic low back pain. Several longitudinal studies, including the Framingham Study23 and the Baltimore Longitudinal Study of Aging,24 demonstrate a strong relationship between obesity (BMI >30) and radiographic knee OA. Additionally, Lee et al found that higher BMI and less weekly moderate-intensity activity significantly contributed to current arthritic pain among older adults with osteoarthritis.25 Most recently, Frilander and colleagues showed that BMI at age 20 in men was significantly related to knee pain later in life, with the development of severe obesity increasing the risk of knee pain by 80%.26

Obesity is thought to cause knee osteoarthritis by increasing the mechanical load to the joints.27 Interestingly, obesity has also been associated with an increased risk of hand OA28 and neuropathic pain,29 which are usually thought to be unrelated to the weight load on the musculoskeletal system. Several other mechanisms that could link obesity and the increased risk for chronic pain include psychological factors such as depression, sleep dysfunction, and increases in pro-inflammatory cytokines associated with adipose tissue accumulation. Pro-inflammatory cytokines can cause sensitization of the whole nociceptive system, increasing the risk for the development of chronic pain.30,31

Maintaining a healthy weight through regular physical activity and consuming a whole-foods-based diet should reduce older adults’ risk of developing the aforementioned types of chronic pain. The management of body weight, while multifactorial, relies, in part, on energy balance. Regular physical activity is a key component in increasing energy expenditure to promote weight loss and even more so to prevent weight regain. To facilitate attaining and maintaining a healthy weight, the scientific evidence points to a need for individuals who are overweight or obese to exceed the public health recommendations of 150 minutes of moderate physical activity per week.20 Thus, ACSM currently recommends progressing to over 250 minutes of moderate physical activity per week, which should be performed over 5 to 7 days per week (Table 1).

Central Modulation of Pain

An age-related decline in central pain modulatory processes may be 1 mechanism that places older adults at an increased risk for the development of chronic pain compared to younger adults. Specifically, older adults exhibit a diminished descending pain inhibitory capacity32,33 and a sensitized central pain system.34,35 An imbalance of these systems likely underlies the increased transition from acute to chronic pain associated with aging.36 Indeed, greater facilitation of pain and a reduced capacity to inhibit pain on dynamic quantitative sensory tests (QSTs) is a shared characteristic of many chronic pain syndromes (ie, fibromyalgia, back pain, osteoarthritis) whose prevalence is common in older adults,37-40 is associated with increased reports of clinical pain even in healthy adults,34,41 and predicts the transition from acute to chronic pain following surgery.42

Recent data suggest that physical activity may play a key role in the functioning of the pain modulatory systems in older adults. This author and colleagues examined whether objective measures of physical activity predicted pain inhibitory capacity and pain facilitation on quantitative sensory tests in healthy older adults without chronic pain.43,44 The results indicated that older adults who participated in more moderate to vigorous physical activity daily exhibited less pain facilitation on QSTs, even after controlling for demographic and psychological variables.43,44 Therefore, participation in moderate to vigorous physical activity could be a favorable strategy to attenuate pain facilitatory processes and potentially decrease risk for development of chronic pain in older adults.

Interestingly, the data also revealed that sedentary behavior and light physical activity in older adults were strong predictors of endogenous pain inhibitory capacity.43,44 Older adults who had relatively less sedentary time and did more light physical activity exhibited greater inhibition of pain on QSTs. While the short- and long-term effects of sedentary behavior on pain outcomes have not been widely documented, sedentary behavior has emerged as a new and potent risk factor for mortality and many health conditions, irrespective of time spent in moderate to vigorous physical activity.45 Alarmingly, the most sedentary group in the United States is adults age 60 years and older, with up to 80% of their awake time spent in an inactive state.46 These preliminary data suggest that sedentary behavior may play a key role in the decline of endogenous pain inhibitory capacity in older adults. These findings are supported by several studies supporting an association between pain modulatory function and physical activity in healthy younger adults,47,48 triathletes,49 and fibromyalgia patients.50 However, prospective studies or intervention studies examining manipulations of physical activity on central pain modulation do not exist.

Based on existing research, clinicians should encourage all able-bodied older adults to adopt a whole-day approach to physical activity.51 This approach advocates encouraging patients to go beyond the ACSM guidelines of 150 minutes of moderate activity per week, by adopting a mindset in which every potential opportunity for sedentary time is replaced with light physical activity. Light physical activity includes activities such as leisurely walking, light housework, yard work and gardening, cooking, and leisurely sports such as table tennis or walking the dog.

While the benefits of replacing sedentary behavior with light physical activity are just coming to light, specific recommendations for light- intensity physical activity and sedentary time do not exist. A recent study did indicate, however, that engaging in over 300 minutes (42 minutes/day) of light physical activity per week was associated with more favorable health biomarker levels (ie, BMI, C-reactive protein, insulin resistance) and fewer chronic diseases in older adults.52

Conclusion

Accumulating evidence indicates that physical activity pursued throughout waking hours may protect against the development of chronic pain in older adults. However, more research is needed to determine the characteristics of optimal physical activity programs for chronic pain prevention in those over age 60. Presently, older adults should be encouraged to at least meet ACSM’s guidelines for exercise for older adults with the goal to exceed the recommendations if weight loss is desired. Furthermore, older adults should be encouraged to be active throughout the day with light physical activity, while minimizing prolonged sedentary time.

Last updated on: September 26, 2017
Continue Reading:
Levorphanol: An Optimal Choice for Opioid Rotation

Join The Conversation

Register or Log-in to Join the Conversation
close X
SHOW MAIN MENU
SHOW SUB MENU