Published December 31, 2020
How common are different diseases throughout the world? How disabling are they? And what are the risk factors that lead to them?
These are the questions that are the focus of The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), which since the 1990s has provided a comprehensive look at hundreds of diseases, across hundreds of countries throughout the world, with the goal of helping to advance understanding of the health challenges we all now face in the 21st century.
Further, according to the Institute for Health Metrics and Evaluation at the University of Washington, which leads the GBD effort, “By tracking progress within and between countries, it [GBD] provides an important tool to inform clinicians, researchers, and policy makers, promote accountability, and improve lives worldwide” (read more here).
Of the diseases that the GBD tracks, musculoskeletal conditions prove to be among the most common across the globe, with enormously detrimental effects on the lives and functioning of the individuals who have these conditions. Our latest data visualization, which relies on data from The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016), published in The Lancet in 2017, tells the story of the burden of musculoskeletal conditions throughout the world.
The visualization reveals that MSK conditions like low back pain and osteoarthritis affect billions of people throughout the world, resulting in a tremendous toll of disability. We aim for this visualization to illuminate the scope of the problem of musculoskeletal conditions and spur increasing recognition of and attention towards this serious issue, which continues to worsen over time.
Editor’s note: While this visualization was in production, The Lancet published new data from the GBD project, updating the data through 2019 (see here). With regard to musculoskeletal conditions, overall, the updated data is highly consistent with the GBD 2016 data upon which this visualization is based. See the end of this visualization for a brief discussion of the update and how the new data compares to the 2016 data.
Part 1: The prevalence of non-communicable diseases
Part 1 of the visualization provides a snapshot of how common non-communicable diseases, including MSK conditions, are throughout the world; the larger the circle, the more common the disease.
Among non-communicable diseases, MSK disorders are extremely common, affecting almost 1.3 billion people in 2016. Still, other non-communicable diseases were even more common than MSK disorders. For example, the prevalence of diabetes, urogenital, blood and endocrine diseases was almost 3 billion; neurological diseases around 2.6 billion; and “other” non-communicable diseases (a broad category including congenital anomalies, skin diseases, sense organ diseases, and oral disorders) reached 5.3 billion. The prevalence of mental and substance abuse disorders was 1.1 billion; chronic respiratory diseases (CR), 571 million; cardiovascular diseases (CV), 469 million; digestive diseases (D), 262 million; chronic liver diseases (CL); 46 million; and neoplasms (N) 43 million.
Part 2: The prevalence of MSK disorders
Part 2 drills down further into the prevalence specifically of MSK conditions. In 2016, among MSK conditions, low back pain ranked at the top, with a prevalence of 511 million, followed by other MSK conditions, osteoarthritis (OA), neck pain, gout, and rheumatoid arthritis (RA).
Part 3: Years lived with disability from non-communicable diseases
Prevalence, however, is just one way to understand the global burden of disease. Another way to look at the issue is to measure how a disease actually affects people’s lives and functioning. Years lived with disability (YLDs) is one such measurement; it refers to the number of years lived in less than ideal health.
Part 3 of our visualization looks specifically at YLDs from non-communicable diseases. Here the burden of MSK conditions really begins to come into view. For instance, even though, as depicted in part 1 of the visualization, neurological conditions are more prevalent than MSK conditions, MSK conditions actually caused twice the number of YLDs (138 million) compared to neurological conditions (69 million) in 2016. In fact, MSK conditions trailed only mental and substance abuse disorders (150 million YLDs), and other non-communicable diseases (150 million YLDs).
Part 4: The causes of YLDs across the world
Part 4 depicts the top 10 causes of YLDs, according to geographic region. Here, the burden of MSK conditions appears particularly stark: some type of musculoskeletal condition – usually low back pain – was the number one or number two cause of YLDs in virtually every region of the world, in 2016. Further, in most regions of the world, 3 or 4 of the top 10 causes of YLDs were MSK conditions. (Gray circles represent non-MSK conditions).
Part 5. DALY trends over time for non-communicable diseases
Part 5 depicts how the burden of disease has changed over time, focusing on another measure, called disability-adjusted life-years (DALYs). This is the sum of YLDs and years of life lost because of premature mortality; one DALY equals one lost year of healthy life. Here, it becomes evident that the contribution of non-communicable diseases, which includes MSK conditions, to DALYs has grown from 1.1 billion in 1990 to 1.5 billion in 2016. The contribution of communicable diseases to DALYs decreased from 1.1 billion in 1990 to 668 million in 2016, while the contribution of injuries to DALYs remained stable over that time period.
Part 6. MSK trends over time
As part 5 showed, the burden of non-communicable diseases, as a whole, has gotten worse over time. That includes MSK conditions. Here, part 6 shows that the burden of every single type of MSK condition has grown over time. For instance, low back pain accounted for 39 million DALYs in 1990, 49 million DALYs in 2006, and 58 million DALYs in 2016. A similar story emerges for other MSK conditions, neck pain, osteoarthritis (OA), rheumatoid arthritis (RA) and gout, with the contribution of each of these to DALYs showing an increase from 1990-2016.
Recently, new data from the GBD project was published in The Lancet, with updates made through 2019. What does this new data say about MSK conditions, compared to 2016? The essential message remains the same: MSK conditions continue to contribute immensely to the global burden of disease throughout the world and are usually the most significant contributors. For instance, when including both sexes combined and all ages:
- In 2019, MSK conditions remained the number 1, 2 or 3 cause of YLDs in almost every major region that the GBD project considers
- When considering all regions together, MSK conditions were the number 1 cause of YLDs in 2019
- In 2019, MSK conditions were responsible for 147 million YLDs globally
- In terms of trends over time, just as in 1990, among non-communicable diseases globally, MSK conditions were again the number one cause of YLDs in 2019
- In 2019, low back pain was the #9 leading cause of DALYs globally, compared to 1990 when it was #13.
In short, the updated data confirm the scope of the problem and make clear that those who aim to mitigate the global burden of disease must make the alleviation of MSK conditions a top priority.
Dale George, PhD, is a postdoctoral research fellow at Feinberg School of Medicine, Northwestern University, US.