The most extensive and in-depth study of global health trends to date, Global Burden of Disease Study 2013 (GBD 2013) finds that more than 95 percent of the world's population has health problems, with more than a third of us experiencing five or more conditions. Lead author of the study Prof. Theo Vos, of the Institute of Health Metrics and Evaluation at the University of Washington in Seattle, and colleagues set out to calculate up-to-date estimates of disease and injury incidence and prevalence among 188 countries between 1990 and 2013, using data from more than 35,000 sources.
The team also sought to estimate the number of disability-adjusted life years (DALYS) - that is, the number of healthy years lost due to illness - over the 23-year period. Prof. Vos and colleagues found that in 2013, only 1 in 20 people (4.3 percent) around the globe had no health problems, meaning more than 95 percent of us had one or more illnesses.
The researchers found that 2.3 billion people worldwide - more than a third of us - had at least five health conditions in 2013. Over the 23-year study period, the number of people with 10 or more health conditions rose by 52 percent.
The number of healthy years lost due to illness increased from 21 percent in 1990 to 31 percent in 2013, and the number of years lived with disability (YLD) rose from 537.6 million in 1990 to 764.8 million in 2013.
The researchers attribute the increase in YLD over the 23-year period to population growth and aging. They found that the main drivers for YLD were musculoskeletal disorders, mental illnesses, substance abuse disorders, neurological conditions and chronic respiratory disorders. The study found that in 2013, musculoskeletal disorders, such as low back pain and arthritis, and mental and substance use disorders - particularly anxiety, depression and drug and alcohol use disorders - accounted for almost 50 percent of all health loss globally.
Low back pain and major depression were ranked as two of the top 10 disability contributors in 2013 among every country. These conditions caused more health loss than chronic obstructive pulmonary disease (COPD), diabetes and asthma combined, according to the results.
Perhaps one of the most important findings was that rates of disability as a result of health problems are not declining as rapidly as death rates from such conditions. Pointing to diabetes as an example the team notes that while diabetes rates rose by 43 percent between 1990 and 2013, death rates from the condition only increased by 9 percent.
Large, preventable causes of health loss, particularly serious musculoskeletal disorders and mental and behavioral disorders, have not received the attention that they deserve, says Prof. Vos. He adds, “Addressing these issues will require a shift in health priorities around the world, not just to keep people alive into old age, but also to keep them healthy."