Individuals, households, and health systems devote enormous resources to curing, preventing, and eliminating non‐fatal, disabling health conditions. Therefore, it is essential that some form of measuring and tracking of non‐fatal burdens be available for policy and planning purposes.
The primary goal of this study was to quantify disability from all major diseases and injuries by country and over time. In the GBD, non‐fatal health experience is quantified using years lived with disability (YLDs). YLDs are the prevalence of condition multiplied by the disability weight for that condition. Disability weight is a measure of severity.
This publication presents estimates of YLDs by region, age, and sex over time from 1990 to 2010. Of the 291 diseases on the GBD cause list, 289 of them cause disability. The 289 diseases and injuries cause 1,160 different disabling sequelae. Sequelae are health conditions that result from those diseases and injuries. The authors analyzed the following factors: prevalence, incidence, remission, duration, excess mortality, and cause‐specific mortality. Sources included published studies, case notification, population‐based cancer registries, other disease registries, antenatal clinic sero‐surveillance, hospital discharge data, ambulatory care data, household surveys, other surveys, and cohort studies.
For the majority of the non‐fatal but disabling health conditions, the authors used research methods designed to address key barriers in data, including missing information, inconsistency, and large methodological variation between data sources. For some conditions, natural history models, geospatial models, back‐calculation models, or registration completeness models were used. Disability weights for 220 unique health states were used to capture the severity of health loss.
As people around the world live longer, they are spending more years with illnesses. With a few exceptions, many of these illnesses are not major causes of death, concluding that what ails you is not necessarily what kills you.
Musculoskeletal disorders are causing a surprisingly large share of the disease burden around the world. In every region, regardless of income or other demographic factors, low back pain and neck pain rank high on the list of causes of YLDs. Low back pain is the leading or second leading cause of YLDs in 17 of the 21 regions.
Mental and behavioral disorders are also major causes of disability. Major depressive disorder is one of the top four causes of YLDs in every region. Anxiety disorders, drug use disorders, alcohol use disorders, schizophrenia, and bipolar affective disorder all rank in the top 25 causes of disability in every region, far higher than other conditions. By age 5, mental and behavioral disorders become an important and soon dominant cause of YLDs, peaking between ages 20 to 29, when they account for 36% of all health loss.
Other specific disorders that continue to significantly contribute to disability are iron‐deficiency anemia, neck pain, chronic obstructive pulmonary disease, anxiety disorders, migraines, and diabetes. Additionally, the burden of falls has gone up 46%, which is primarily due to aging.
The vast majority of YLDs – 78.6% of them – are caused by noncommunicable diseases. The remainder of YLDs are caused by either communicable, maternal, neonatal, and nutritional causes or injuries. Neglected tropical diseases, HIV/AIDS, tuberculosis, malaria, and anemia remain important causes of YLDs in sub‐Saharan Africa.
Of the top 50 most prevalent non‐fatal but disabling health conditions, four are oral health conditions (dental caries of permanent teeth, chronic periodontics, dental caries of baby teeth, and edentulism). Four skin diseases are also extremely common: fungal skin disease, acne vulgaris, pruritus, and eczema; collectively these conditions affect 2.1 billion individuals worldwide.
Health priorities have, for much of the past 100 years or more, been largely driven by the desire to improve survival rates, particularly of children. However, societies also expend substantial resources on keeping people healthy – not only keeping them alive into old age. The cost of taking care of the disabling conditions identified in GBD 2010 is large, and population growth and particularly aging will steadily increase their burden. It is important to understand whether there are strategies to effectively deal with this increasing burden and determine which strategies are the most effective.
This study demonstrates that it is possible to quantify health loss among the living using comparable metrics that identify the leading causes of non‐fatal illness in different regions, at different ages, and at different points in time. Its findings indicate that mental health, musculoskeletal health, and diabetes are major contributors to health loss, and monitoring progress in reducing the impact of these non‐fatal ailments is as important for improving health as monitoring progress against the leading causes of death.
Effective and affordable strategies to deal with the rising burden of non‐fatal health outcomes are an urgent priority for health systems in most parts of the world. Further and ongoing quantification of the burden will be critical to understanding how well health systems are responding to these challenges.