Low back pain in the context of global public health and universal health coverage
Low back pain (LBP) is a very common condition experienced by most people at some point in their lifetime (8). The experience of LBP may occur at any point across the life course from childhood to older age (9).
In 2020, an estimated one in 13 people globally experienced LBP (age-standardized point prevalence of 7.5%). This equates to 619 million people, and represents an increase of 60% in cases compared with 1990 estimates (10). The Global Burden of Disease (GBD) study estimates suggest the prevalence rate per 100 000 for LBP increases from about age 15 years and peaks in older age at 85 years. Similarly, the rate of disability (years lived with disability (YLDs) per 100 000) is greatest in older age (80–84 years), highlighting the importance of clinical guidelines for older people. Prevalence and disability estimates are consistently higher in females. While the absolute number of cases and YLDs are greatest in middle age, growth in prevalent cases increased most dramatically in older people from 1990 to 2019: from 46.6 to 92.7 million for adults 70 years and older and from 13.9 to 33.1 million for adults aged 80 years and older. Most of the GBD health estimates for LBP are derived from studies examining chronic LBP.
Low back pain is the leading cause of disability globally across all ages and in both sexes, representing 8% of all YLDs in 2020 (10).
Similar patterns are observed in four of the six WHO regions (Eastern Mediterranean, Europe, Americas and Western Pacific), although there are limited primary data available for many low- and middle-income countries creating uncertainty in national-and regional level estimates (11). In the WHO regions of Africa and South-East Asia, LBP is ranked second and third for disability burden, respectively. Global disability estimates (YLDs) attributed to LBP increased by 59% from 1990 to 2020, being largely ascribed to population growth and ageing, with the largest increases observed in low- and middle-income countries (10). The scale of LBP-related disability in low- and middle-income countries is also attributed to lower socioeconomic status and physically demanding occupations (12). Although prevalence data for LBP in these settings are sparse (11) and the experience of musculoskeletal pain varies greatly between cultures (13), synthesized available evidence points to a high prevalence across the life course and significant burden (12, 14). Current health estimates suggest LBP cases and the associated burden will increase globally in coming decades.
By 2050, the total number of LBP cases is expected to increase by 36% to 843 million people, with the greatest increase expected in the continents of Africa and Asia, largely due to population growth and ageing (10).
Prevalence, health burden and economic cost associated with LBP continue to rise, care variation and critical knowledge and skills gaps among health workers persist, and delivery of care that is not evidence-based remains commonplace (15, 16). While many national or regional clinical guidelines for chronic LBP have been developed, they have predominately been developed in high-income countries. No global guidelines exist for the management of chronic LBP in adults. In particular, there is an absence of evidence-based recommendations for the management of chronic LBP in older people. The present guideline addresses chronic LBP as a global public health issue and aims to address this gap for chronic LBP experienced by older people. The guideline supports other activities undertaken by WHO in improving outcomes for adults with LBP and supports the WHO Integrated care for older people (ICOPE) approach – one of the action areas of the UN Decade of Healthy Ageing (2021–2030).
Universal health coverage (UHC) means that all individuals and communities receive the health services they need without suffering financial hardship. It includes the full spectrum of essential, quality health services and products – from health promotion to prevention, treatment, rehabilitation and palliative care across the life course. In consideration of the global health burden attributed to LBP, management of LBP is relevant to UHC. In order to attain UHC, health systems must be oriented towards a primary health care (PHC) approach, which is the most inclusive, equitable, cost-effective and efficient approach. In most settings, chronic primary LBP (CPLBP) is managed initially in primary and community care settings, hence the focus of the guideline on interventions relevant to precisely these settings. It entails improving access to effective and acceptable interventions for people with LBP in local health care settings while engaging and empowering individuals, families, households and communities towards increased social participation and enhanced self-care.
Definition of chronic primary low back pain
Chronic primary low back pain (CPLBP) is defined as a persistent or recurrent pain experience of greater than three months that is not reliably attributed to an underlying disease process (e.g. an inflammatory auto-immune condition such as axial spondyloarthritis, malignancy, infection), structural lesion (e.g. fracture) or deformity. While the experience of pain is often associated with emotional distress and/or functional disability (1), minimum thresholds for distress and disability were not applied when developing the guideline. The ICD-11 classification of CPLBP falls under MG30.02 Chronic primary musculoskeletal pain.
Chronic primary low back pain accounts for the vast majority of chronic LBP presentations in primary care, commonly estimated to be at least 90% of cases (9, 17), due to the inability to reliably identify responsible nociceptive sources arising from body tissues or structures which might explain persistent or recurrent LBP experiences.
For these reasons, the guideline focuses on this classification group and does not consider specific LBP presentations (i.e. chronic secondary low back pain), which represent a minority in primary care practice (18). While effective interventions and pathways of care do exist for some chronic secondary LBP conditions, unwarranted care variation and evidence-practice gaps are largest for CPLBP (8, 9, 15).
Concurrent spine-related leg pain may also be experienced with CPLBP (19, 20), and trials often sample mixed populations of adults with and without spine-related leg pain. Concurrent spine-related leg pain is usually associated with a higher level of symptom severity and disability (19, 21).
Consequences of chronic low back pain in adults
Most people with an episode of acute LBP experience time-limited, low-to-moderate levels of disability and a favourable clinical course. Often, the experience of LBP is recurrent, with several episodes experienced across the life course (22–24), more frequently in older age (25). Evidence suggests a median 26% of people (range 2–48%) presenting with acute LBP in primary care go on to experience chronic LBP with associated disability at 3–6 months, and 21% (range 7–42%) at 12 months (26). Other data highlight that up to two thirds of people who experience an episode of acute LBP continue to experience symptoms that persist beyond 12 months, often in a fluctuating pattern (27, 28), while in older people persistence of symptoms is common (29). Importantly, people experiencing CPLBP and high levels of disability account for the majority of all disability and costs attributed to LBP (8), and the societal costs of chronic pain (of which chronic LBP is the major contributor) exceed those of cancer and diabetes combined (30).
In low- and middle-income countries, the experience of chronic LBP is 2.5 times more prevalent in working populations compared to non-working populations (31). Optimizing clinical management of people with CPLBP is therefore a current global public health priority.
The impacts of LBP are cross-sectoral and wide-ranging (8). Chronic LBP is often associated with significant disability, reduced ability to participate in family, social and work roles, and incurs major costs to families, communities and health systems (e.g. up to US$ 100 billion per annum when indirect costs are also considered) (32). People with chronic symptoms, particularly older people, are more likely to experience poverty, prematurely exit the workforce (33) and accumulate less retirement wealth (34). In both high-income and low- and middle-income countries, experiences of disabling LBP and early retirement because of chronic symptoms are more common among people of lower socioeconomic status, thus contributing to further poverty and social inequity (35–39). Despite people commonly seeking care for LBP and substantial healthcare spending, health outcomes have not improved over time (40, 41).
Low back pain and healthy ageing
In older people, LBP is very common and the most common health problem that results in loss of intrinsic capacity (physical and mental capacities) (42); it is a common reason for care seeking (40).
Rapid population ageing, particularly in low- and middle-income countries, will increase the number of older people experiencing LBP.
Compared to younger people, adults aged 60 years and over are more likely to experience disabling, persistent and recurrent episodes of LBP (43–45). In 2019, the point prevalence of LBP among older people ranged from 12.9 to 19.1% at age 60–64 to 20.4 to 25.3% at age 80–84 years across WHO regions (Institute for Health Metrics and Evaluation data source, powered by WHO Maternal, newborn, child and adolescent health and ageing data portal). For many older people, LBP is particularly burdensome because it restricts mobility and thus the ability to be active and participate in society (27), thereby leading to possible psychosocial impacts (46–48). LBP in older people is associated with comorbidities and higher mortality when compared with older people who do not report LBP (42, 49–53). LBP in older people is strongly related to a decrease in health-related quality of life, particularly when spine-related leg pain is also experienced (54). In particular, concurrent musculoskeletal pain, loss of mobility, falls, urinary incontinence and poor sleep are important adverse health outcomes associated with LBP in older people (20, 55, 56), and a bidirectional relationship has been established between chronic musculoskeletal pain and frailty in older people (57). The WHO integrated care for older people (ICOPE) approach highlights the importance of timely management of musculoskeletal pain to improve locomotor capacity and other domains of intrinsic capacity (58), as a part of a personalized assessment and care plan.
Evidence-based clinical guidelines for management of LBP are based on research, performed almost exclusively on younger and middle-aged adults. There are no guidelines specifically providing recommendations for management of LBP in older age (>60 years) (59, 60). Given the high prevalence of CPLBP in older people, consequent function and participation restrictions and the need for personalized care in some contexts, especially for medicines, there is a need for evidence-based, multidisciplinary guidelines for the management of CPLBP in adults which explicitly consider older people.
Recent guidance points to the importance of considering pharmacological and nonpharmacological interventions for older people, consistent with their care experiences, values and preferences (48).
