Low Back Pain in Older Adults: Understanding Risk Factors, Management Options, and Future Directions

The average life expectancy of humans has increased dramatically in the last decade due to the advancement of medicine. According to the United Nations, the world’s population of people aged 60 and over will triple by 2050. In the UK alone, around 22% of the population will be aged 65 or over in 2031, surpassing the number of under-25s.

However, the rapid growth of the aging population also increases the likelihood of non-communicable diseases (e.g. musculoskeletal complaints). Studies have suggested that the prevalence of musculoskeletal pain in older adults ranges from 65 to 85% and 36 to 70% of them suffer from back pain.

Low back pain (LBP) is the most common health problem among older adults that causes pain and disability. Older adults, ages 65 and older, are the second most common age group to visit the doctor for low back pain.

Previous research suggests that the prevalence of low back pain increases progressively from adolescence to age 60 and then declines, which may be attributed to occupational exposure among working-age adults or to age-related changes in pain perception or stoicism. . However, recent studies have revealed that low back pain remains ubiquitous among older adults of retirement age.

In population-based studies, the one-year prevalence of low back pain in community-dwelling older people ranged from 13 to 50% worldwide. Similarly, while up to 80% of older residents in a long-term care facility experience substantial musculoskeletal pain and one-third of these cases are low back pain, older residents’ pain is often underreported and treated inappropriately.

While undertreatment of low back pain in older adults may be attributed to avoidance of prescribing high-dose analgesics (e.g., opioids), it may also be attributed to difficulty identifying the presence or causes of low back pain.

Research has shown that less than 50% of primary care physicians have high confidence in diagnosing the causes of chronic low back pain in older adults. Consequently, this may result in overreliance on medical imaging or inadequate management of low back pain (e.g., undertreatment).

Imperatively, failure to treat or undertreat older adults with low back pain can lead to sleep disturbances, withdrawal from social and recreational activities, psychological distress, impaired cognition, malnutrition, rapid decline in functional capacity, and falls. These low back pain-related consequences can compromise your quality of life and increase your long-term healthcare expenses.

Although several medical associations have published clinical guidelines on the conservative treatment of chronic pain in older adults, there is a paucity of literature summarizing the various causes or risk factors for developing severe/chronic low back pain among older adults.

Since a better understanding of these factors may improve the management of low back pain, the objectives of the current narrative review were to summarize the potential causes of low back pain, risk factors for chronic low back pain, special consideration for pain management lumbar (e.g., pain assessments in patients with dementia) in older people. people aged 60 years and older, and future research directions.

> Nonspecific or mechanical low back pain

As among young adults, the majority of low back pain among older adults has no defined pathology (e.g., fracture or inflammation) and is diagnosed as nonspecific low back pain . These patients experience low back pain that is altered by posture, activity, or time of day.

Nonspecific low back pain can originate from different sources of pain.

Disc degeneration on magnetic resonance imaging (MRI) is more common with age progression and, as such, in older adults; however, it is less likely to be the source of pain compared to young adults. In contrast, facet joint pain in older people may present as localized lower back pain with or without pain in the back of the thigh when walking. Pain may worsen during trunk extension, ipsilateral lateral flexion, and/or rotation

. Lumbar degenerative spondylolisthesis (defined as the forward or backward sliding of a cephalic vertebra over a caudal one secondary to a degenerated disc and altered facet joint alignment) is common among women aged 60 years and older and is usually associated with facet hypertrophy.

The presence of degenerative spondylolisthesis along with facet hypertrophy and thickening of the ligamentum flavum can lead to pain, spinal stenosis, and neurological deficits in older adults. Although spinal degenerative changes can induce low back pain, not all lumbar medical imaging abnormalities are related to low back pain because abnormal imaging phenotypes are ubiquitous among asymptomatic older adults.

>  Radiculopathy

While nonspecific low back pain is usually located in the lumbar region and/or thigh, compression of nerve roots or spinal meninges by degenerated spinal structures (e.g., herniated disc, facet joints, and/or epidural fat) ) [54] can lead to radiculopathy that radiates distal to the knee. The clinical presentation of radiculopathy depends on the location of neural tissue compression.

Lumbar spinal stenosis (LSS) secondary to degenerative changes (eg, osteophytes and hypertrophic ligamentum flavum) at one or multiple levels can produce unilateral or bilateral radiculopathy and neurogenic claudication with or without low back pain. Neurogenic claudication is characterized by numbness and heaviness of the legs after prolonged walking, which may be relieved by a flexed position (eg, leaning forward or sitting).

>  Osteoporotic vertebral fractures

Given the hormonal changes that follow menopause, women are more susceptible to osteoporotic fractures and related low back pain. Approximately 25% of all postmenopausal women suffer vertebral compression fractures and the prevalence of this condition increases with age. It is estimated that the prevalence of vertebral compression fractures in women aged 80 years or older can reach 40%.

Compared to patients with nonspecific low back pain, patients with vertebral fractures experience more disability. Unfortunately, only a third of cases are correctly diagnosed because many older people assume that bone and joint pain is part of the aging process. As such, clinicians should pay more attention to examining older people with acute onset of localized low back pain that may or may not present with paraspinal muscle spasm.

A recent systematic review suggests that advanced age, corticosteroid use, and major trauma are risk factors for vertebral fractures. The common site of compression fractures occurs in the thoracolumbar region. Depending on the mechanism of the fractures, some vertebral compression fractures can result in radiculopathy. The most common fracture mechanism is due to a bending movement or trauma that causes an anterior wedge fracture.

>  De novo degenerative lumbar scoliosis

De novo degenerative lumbar scoliosis (DNDLS) is a spinal deformity in older adults that results in disabling low back pain/leg pain and suboptimal quality of life. DNDLS is defined as a lumbar scoliotic curve with a Cobb angle ≥10° in the coronal plane that develops after age 50 years in people without a history of adolescent idiopathic scoliosis.

The reported prevalence of DNDLS in the adult population has ranged between 8.3 and 13.3%, while in adults over 60 years of age it reaches 68%. Multifactorial causes have been suggested for DNDLS, including intervertebral disc degeneration and genetic predisposition.

> Tumors/cancers

Incidence rates of all malignancies increase exponentially with age [88], although only less than 1% of causes of low back pain presented to primary care physicians are attributed to spinal tumors. Most of these tumors are related to metastasis and only a handful of them are primary tumors. Common metastatic sources of low back pain are the prostate and kidney, although primary malignant tumors (eg, chordoma, plasmacytoma, or lymphoma) are also found in older adults.

>  Spinal infection

Vertebral osteomyelitis ( VO) is a life-threatening infectious musculoskeletal disease in older people caused by infection of the vertebral bones. Given the increasing aging of the population, the incidence of OV is increasing.

Although the reported incidence rate of OV in the general population only varies from 2.5 cases to 7 cases per 100,000 person-years, the mortality of these patients can be as high as 12%. Four causes of VO have been suggested.

First, pathogenic bacteria can spread hematogenously from a distant infected source and multiply in the metaphyseal arterioles of the vertebral bone, leading to the formation of microabscesses, bone necrosis, and fistula within the bone. Staphylococcus aureus is the most common pathogen.

Secondly, tuberculous OV can occur in older people who have contracted tuberculous infection at a young age. Mycobacterium tuberculosis can be transmitted and remain in the vertebral bone.

>  Visceral diseases

Since it is not uncommon for older people to have comorbidities, it is important to consider other non-spinal pathologies that usually present as chronic low back pain. Several visceral diseases (eg, dissecting abdominal aortic aneurysm, cholecystolithiasis, nephrolithiasis, prostatitis, urinary tract infection, and pelvic inflammatory disease) are known to generate symptoms comparable to chronic low back pain.

>  Cauda equina syndrome

This syndrome is attributed to the compression of multiple lumbar and sacral nerve roots in the spinal canal that cause intestinal, bladder or sexual dysfunction, as well as numbness of the perianal region.

Depending on the location of nerve root compression, patients with cauda equina syndrome may or may not experience sciatica.

Possible causes of this syndrome include central disc herniation or spondylolisthesis at the lower lumbar levels, spinal tumors, dislocated fractures, and abscesses within the spinal canals. Furthermore, this syndrome may be secondary to some rare iatrogenic causes (eg, spinal anesthesia or postoperative hematoma).

Although most low back pain is self-limiting and begins to improve after a few days and resolves within a month, some patients are susceptible to chronic low back pain that leads to significant disability.

While age is a well-known risk factor for chronic low back pain, other factors may perpetuate low back pain in older adults.

Understanding these factors can help identify high-risk patients and improve their management of low back pain. Since older adults generally face age-related physical and psychosocial problems, comprehensive evaluations and treatments are needed to effectively manage low back pain in older people.

Although a comprehensive history, self-reports of pain characteristics and pain-related disability, as well as an appropriate physical examination, are necessary for the differential diagnosis among older adults with low back pain, attention should also be paid to the evaluation and the treatment of older adults with low back pain to optimize pain management.

The American Geriatrics Society has published recommendations on pain management for geriatric patients with nonmalignant pain. In particular, a standing order of pain reliever (eg, acetaminophen) is recommended for older adults with chronic pain so that they can have a constant concentration of pain reliever in their bloodstream.

Tramadol is recommended to be prescribed with caution to patients with a known risk of seizures (e.g., stroke, epilepsy, and head trauma) or for those taking medications that may lower the seizure threshold (e.g., neuroleptics and tricyclics). . Additionally, the guideline also suggests that if acetaminophen fails to control pain, nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g., COX-2 therapy or non-acetylated salicylates) may be used as adjunctive therapy.

However, since some traditional NSAIDs can cause gastrointestinal discomfort, physicians are recommended to prescribe non-acetylated salicylates for older patients with peptic ulcer and gastrointestinal bleeding. Although there is no ideal dose for prescribing opioids among older adults with low back pain, the effective dose should be carefully adjusted to fit individual needs.

To achieve better pain relief with minimal side effects secondary to a high dose of a single medication, it is recommended to simultaneously use two or more analgesics with different mechanisms of action or different classes of medications (e.g., opioid and non-opioid analgesics).

It should be noted that opioids (e.g., codeine) may increase the risk of falls and other drug-related adverse effects (e.g., depression, nausea, tachycardia, seizures, or falls in older patients who have not received opioids). during the opioid initiation period (i.e., within the first 3 months) or during the use of long-acting opioids. Therefore, specific education and caution should be provided to these patient groups.

Additionally, because older patients with chronic low back pain are commonly associated with depression or anxiety, it is not uncommon for them to take antidepressants (eg, serotonin reuptake inhibitors) or benzodiazepines.

Since some of these psychotropic drugs can compromise their memory, cognition, alertness and motor coordination, special attention should be paid to these patients to minimize the risk of falls, hip fractures or traffic accidents. For example, co-prescribing tramadol and selective serotonin reuptake inhibitor (an antidepressant) may increase the risk of serotonin syndrome (e.g., hyperthermia, agitation, diarrhea, tachycardia, and coma) which can lead to sudden death.

If patients are at high risk for opioid overdose (e.g., alcoholism, history of opioid overdose/drug abuse, concurrent use of benzodiazepines or sedative hypnotics, or poor compliance with opioid medications), they should undergo evaluation. of overdose risk, urine drug abuse screening prior to opioid prescription, drug overdose education, and frequent clinical follow-up to mitigate your risk.

Additionally, doctors can prescribe naloxone to these high-risk patients and teach them/their caregivers to use it in an emergency. Naloxone is an opioid antidote to neutralize the toxicity of opioid overdoses.

For patients taking long-acting opioids (e.g., oxycodone or methadone) or who have hepatic or renal dysfunction, they should be reassessed periodically to ensure timely tapering or discontinuation of opioids if necessary.

Taken together, existing medical guidelines generally recommend low-dose initiation and gradual titration of opioid therapy and constipation prophylaxis, increased awareness of potential interactions between concurrent medications, as well as close monitoring of responses to opioid therapy. treatment in patients. There is a need to provide updated education to healthcare providers to optimize pain management for older patients with chronic pain.

Although pain medications are the first-line treatment for older people with low back pain, older people with low back pain (especially those with a long history of low back pain) may require other conservative treatments to mitigate pain and restore function. Growing evidence has indicated that some, but not all, conservative treatments may benefit older people with low back pain.

While the effectiveness of various physical therapy modalities in treating older people with low back pain remains controversial, a recent meta-analysis has highlighted that Tai Chi , a mind-body exercise therapy, is an effective intervention for older patients. with chronic pain (including pain, osteoarthritis, fibromyalgia and osteoporotic pain) compared to education or stretching.

Importantly, in addition to pain relief, several systematic reviews on Tai Chi have revealed promising results in improving balance, fear of falling, lower extremity strength, physical function, hypertension, cognitive performance and depression in older people in compared to no treatment or usual care.

Surgical intervention is indicated for older people only if there is a definitive diagnosis of lumbar pathology (e.g., degenerative LSS, cauda equina syndrome, or spinal tumor) that needs to be treated with surgery or that does not respond to conservative intervention . While there are many different lumbar surgical interventions, the goal of these approaches is to minimize compression of neural tissues and/or improve spinal stability.

Decompression surgery (i.e., laminectomy, laminotomy, and discectomy) is used to partially or completely remove lumbar structures that are affecting neural tissues. Recent evidence suggests that minimally invasive spine surgery techniques have a higher success rate than open lumbar decompression surgery.

Unlike decompression surgery, spinal fusion surgery uses bone grafts (autograft or allograft) or surgical devices to fuse adjacent vertebrae anteriorly, posteriorly, or circumferentially. Such surgery immobilizes the spinal motion segment, theoretically eliminating key sources of pain generation and eliminating intersegmental motion of the vertebrae that can compress neural structures to relieve symptoms.

In general, simple and complex spinal fusion surgeries are associated with an increased risk of major complications and postoperative mortality compared with decompression surgery.

While decompressive laminectomy/laminotomy with or without spinal fusion is a common surgical intervention for older patients with degenerative ELL, isolated decompression without spinal fusion is a preferred option for older patients with degenerative lumbar spondylolisthesis without severe low back pain/instability.

However, two recent randomized controlled trials have reported conflicting results regarding the effectiveness of decompression surgery plus spinal fusion versus decompression surgery alone in the treatment of patients with LSS and degenerative spondylolisthesis.

Spinal decompression and fusion are also indicated for patients with symptomatic degenerative lumbar scoliosis, although these procedures may increase the risk of complications in older adults (especially those with comorbidities).

Recently, disc arthroplasty has been adopted to restore mobility of an intervertebral joint by replacing a degenerative disc with an artificial disc and minimizing the risk of adjacent segment degeneration/disease. Although current evidence points to the safety and efficacy of such an intervention for the indication of cervical spine pathology compared to conventional interbody fusion procedures, the results for lumbar disc disorders remain under further evaluation.

Although low back pain is ubiquitous among older adults, the paucity of literature on low back pain trajectories, determinants of chronic low back pain, and effective low back pain management in older adults highlights research gaps in this area.

Because multiple factors (e.g., dementia, psychiatric and physical comorbidities, maladaptive coping, and age-related physical and psychosocial changes) can modify the experience of low back pain in older adults, clinicians should incorporate subjective, observational, and physical examinations. comprehensive as well as proxy reports to make an accurate diagnosis. For patients with persistent low back pain, medical imaging may be ordered to rule out malignant causes of pain.

To minimize undertreatment of older adults with low back pain, it is necessary to recognize the presence of low back pain and titrate analgesics according to individual needs. Through understanding the various factors that contribute to severe/chronic low back pain in older adults, timely and appropriate treatment strategies can be formulated.

Additionally, with a broad understanding of "omics" technologies , study designs and findings, new pain pathways can be identified and novel therapies developed. As such, we are hopeful that, with broadening and deepening the understanding of pain, the treatment of older patients with low back pain may eventually become more personalized or precise and optimize outcomes, leading to a healthier society. and productive.