Prevalence of Asthma, COPD Grows Worldwide

The prevalence of lung conditions worldwide has increased, despite the overall decrease in the prevalence and death rates for asthma between 1990 and 2015, according to the results of the 2015 Global Burden of Disease (GBD) Study.

Largely attributed to population growth and aging, the GBD researchers noted that the disease burden is led by asthma and chronic obstructive pulmonary disease (COPD), which are both preventable and treatable and receive less attention than other non-communicable diseases.

The COPD burden continues to increase globally.

The researchers estimated deaths due to asthma and COPD by analyzing data from vital registration and verbal autopsy for the aggregate category of all chronic respiratory diseases. Disease estimates for asthma and COPD were based on systematic reviews of published papers, unpublished reports, surveys, and health service encounter data.

In 2015, 40 million individuals died from asthma, a decrease of 26.7% from 1990. The age-standardized death rate also decreased by 58.8%. However, asthma remains the most common respiratory disease worldwide, affecting an estimated 358 million individuals in 2015. That year, 3.2 million individuals died from COPD worldwide, an increase of 11.6% from 1990. Additionally, COPD prevalence increased from 1990 to 2015 by 14.7%.

Most of the reductions found were observed in mortality rates, which reflects greater improvements in reducing fatality rather than an overall change in incidence and prevalence, the researchers found. Lower asthma mortality in high-income countries suggests improved access to health services and better treatment options. The greatest disease burden from both COPD and asthma was seen in developing countries.

The researchers determined that the absence of a relationship between asthma prevalence and asthma death rates adds evidence that most asthma deaths at all ages are preventable by treatment with low-dose corticosteroids and other management strategies, along with an avoidance of risk factors.

Higher COPD death rates and prevalence may be linked to an increase in smoking and outdoor pollution. The researchers identified preventable interventions to reduce exposures to risk factors but noted that a considerable proportion of COPD remains unexplained. Other established individual risk factors, such as a low level of physical activity, could also have contributed to the COPD burden.

Overall, the researchers concluded that up-to-date population information for these diseases is necessary for policy decision-making to improve access to and the quality of existing intervention strategies.

Reference

GBD 2015 Chronic Respiratory Disease Collaborators. Global, regional, and national depths, prevalence, disability-adjusted life years, and years lived with disability for chronic obstructive pulmonary disease and asthma, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet Respiratory Medicine. 2017. doi: http://dx.doi.org/10.1016/S2213-2600(17)30293-X.