Contribution of specific diseases and injuries to changes in health adjusted life expectancy in 187 countries from 1990 to 2013: retrospective observational study

OBJECTIVE: To quantify and compare the contribution of 306 diseases and injuries to the changes in health adjusted life expectancy at birth (HALE(0)) between 1990 and 2013. DESIGN: Retrospective demographic analysis based on aggregated data and using life table technique, Sullivan method, and decomposition method for differences in health expectancy. SETTING: The globe, 21 regions, and 187 countries, covered in the Global Burden of Disease Study (GBD) 2013. MAIN OUTCOME MEASURES: Cause specific contribution to changes in HALE(0) between 1990 and 2013 in terms of mortality effect, disability effect, and total effect. RESULTS: Between 1990 and 2013, global HALE(0) increased by 5.31 years for males and 5.73 years for females. The cross national Gini coefficient of HALE(0) for both sexes combined decreased by 15.22% from 0.0736 to 0.0624. HALE(0) declined in 11 countries during the period, predominantly owing to HIV/AIDS except in Belize, Belarus, and Paraguay. Controlling communicable, maternal, neonatal, and nutritional diseases accounted for 56.47% (3.10 years) of changes in HALE(0) for both sexes combined, followed by non-communicable diseases (30.05%; 1.65 years) and injuries (13.67%; 0.75 years). Globally, HIV/AIDS caused the biggest reduction in HALE(0) (–0.28 years) and mainly afflicted residents in southern (–7.86 years), western (–1.53 years), and eastern (–1.38 years) sub-Saharan Africa. Diabetes had the second biggest negative total effect on changes in HALE(0) (–0.12 years), which was quite widespread across regions. Despite their positive total effect in high income regions, such non-communicable diseases as ischaemic heart disease, cerebrovascular disease, and hypertensive heart disease had a negative total effect in many low and middle income regions. Mortality reduction was the predominant driver (93.62%; 5.14 years) for improvement in HALE(0), accompanied by an increase of 0.80 years in life expectancy lived with disability at birth. Only 44 (27%) of 163 causes at level 3 in the GBD cause hierarchy influenced changes in HALE(0), mainly or only through disability. CONCLUSIONS: Between 1990 and 2013, the globe made achievements in not only promoting population health as a whole but reducing health inequality between countries. This study pinpoints the priority diseases and injuries for altering the declining health trend in 11 countries, for curbing the epidemic of non-communicable diseases in low and middle income countries, and for promoting compression of morbidity worldwide. The detailed country specific decomposition results of effects of diseases and injuries on change in population health will further facilitate the development of national health policies.