In a recent, award-winning study, 266 million individuals worldwide (3.63%) were found to have degenerative spine disease and low back pain annually. “Significantly,” the investigators note, “data quality is higher in high-income countries, making overall quantification in low- and middle-income countries less complete.” They conclude that “a global effort to address degenerative conditions of the lumbar spine in regions with high demand is important to reduce disability.”
The paper, authored by Vijay M Ravindra (University of Utah, Salt Lake City, USA) and colleagues, was published in the Global Spine Journal in April 2018, and recently received a Best Paper Award from the journal.
While lumbar degenerative spine disease is a common cause of disability, the authors note that a reliable measure of its global burden does not yet exist. Ravindra and colleagues therefore sought to quantify the incidence of lumbar degenerative spine disease to determine its overall burden across World Health Organisation regions and World Bank income groups.
The investigators found that out of the 266 million individuals worldwide they found to have degenerative spine disease and low back pain each year, the highest and lowest estimated incidences were found in Europe (5.7%) and Africa (2.4%), respectively. They also found that, based on population sizes, low- and middle-income countries have four times as many cases as high-income countries.
In addition, spondylolisthesis was found in 39 million individuals (0.53%) worldwide, symptomatic disc degeneration was noted in 403 million (5.5%) individual, and 103 million (1.41%) individuals worldwide were estimated to have spinal stenosis annually.
Ravindra and colleagues used a meta-analysis to create a single proportion of cases of degenerative spine disease in patients with low back pain. Using this information in conjunction with low back pain incidence rates, they calculated the global incidence of individuals who have degenerative spine disease and low back pain, i.e. their neurosurgical relevance, based on the Global Burden of Disease 2015 database.
The authors remark that while numerous studies have quantified the incidence and prevalence of degenerative spine disease, the combination of sparse high-quality population-based data, competing disease definitions, and specific population samples, coupled with limited literature resulting from underdiagnosis and underreporting of lumbar degenerative spine disease in resource-poor settings, have hindered the ability to produce a global estimate.
Ravindra and colleagues recognise a few limitations of the present study. They note that a topic this general “inherently is reported in populations that are non-uniform, making direct comparisons challenging.” In particular, combining epidemiological data across heterogeneous cohorts risks misrepresentation of disease volume.
In addition, they note that the “paucity” of epidemiological information from low- and middle-income countries likely results in the under-representing of these areas in the overall volume of degenerative spine disease and low back pain.
Finally, a large amount of the literature is focused on elderly, ageing populations. “This likely stems from the notion that degeneration implies an age relation, which is a misnomer that is highly prevalent in the literature,” the authors note.
More generally, the investigators note that additional studies should be undertaken to examine the burden to cervical degenerative disease, degenerative scoliosis, spinal cord injury, spinal infection, and rheumatological diseases that affect the spine “to obtain a more complete picture of the global burden of these diseases.”
Overall, the investigators conclude: “The tremendous amount of data found within the literature cannot possibly be summarised in a single study, but the results are necessary if we are to begin to plan a global public health effort.”