Lower Respiratory Infection Rates Have Decreased Globally, But Remain Burdensome

Lower respiratory infections are the leading infectious cause of death and the fifth-leading overall cause of death worldwide, according to the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2015. However, the global rate of mortality associated with lower respiratory infections in children younger than 5 years has decreased significantly within the past decade.

For their study, the researchers assessed the prevalence of lower respiratory infections in 195 countries. With the Cause of Death Ensemble model, they used age, sex, geography, and year to estimate mortality rates associated with lower respiratory infections. The meta-regression platform DisMod-MR was used to model morbidity, incidence, and prevalence of lower respiratory infections.
__________________________________________________________________________________________________________________________

RELATED CONTENT
Could High-Dose Vitamin D Supplementation Prevent Respiratory Infections?
Respiratory Infections Linked to Myocardial Infarction Risk
__________________________________________________________________________________________________________________________

Childhood undernutrition and air pollution, which are the leading risk factors for lower respiratory infection disability-adjusted life-years (DALYs), were included in a decomposition analysis to establish the relative contribution of changes in DALYs associated with lower respiratory infections.

Results indicated that lower respiratory infections accounted for an estimated 2.74 million deaths and 103 million DALYs worldwide in 2015. The researchers observed that children younger than 5 years had been disproportionately affected by lower respiratory infections, with an estimated 704,000 deaths and 60.6 million DALYs.

Ultimately, the global rate of mortality due to lower respiratory infections had decreased by 36.9% in children ages 5 years or younger, and by 3.2% overall between 2005 and 2015. A total of 1,517,388 (55.4%) deaths across all age groups were caused by pneumococcal pneumonia.

Furthermore, improvements in air pollution exposure had resulted in a 4.3% decrease in DALYs between 2005 and 2015, while improvements in childhood undernutrition had resulted in an 8.9% decrease in DALYs.

“At the global level, the burden of [lower respiratory infections] has decreased dramatically in the last 10 years in children younger than 5 years, although the burden in people older than 70 years has increased in many regions,” the researchers concluded. “[Lower respiratory infection] remains a largely preventable disease and cause of death, and continued efforts to decrease indoor and ambient air pollution, improve childhood nutrition, and scale up the use of the pneumococcal conjugate vaccine in children and adults will be essential in reducing the global burden of [lower respiratory infection].”

—Christina Vogt

Reference:

Troeger C, Forouzanfar M, Rao PC, et al; GBD 2015 LRI Collaborators. Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory tract infections in 195 countries: a systematic analysis for the Global Burden of Disease Study 2015 [Published online August 23, 2017]. Lancet Infect Dis. http://dx.doi.org/10.1016/S1473-3099(17)30396-1.