Asthma in the Americas: An Update: A Joint Perspective from the Brazilian Thoracic Society, Canadian Thoracic Society, Latin American Thoracic Society, and American Thoracic Society

Abstract

Asthma affects a large number of people living in the Americas, a vast and diverse geographic region comprising 35 nations in the Caribbean and North, Central, and South America. The marked variability in the prevalence, morbidity, and mortality from asthma across and within nations in the Americas offers a unique opportunity to improve our understanding of the risk factors and management of asthma phenotypes and endotypes in children and adults. Moreover, a better assessment of the causes and treatment of asthma in less economically developed regions in the Americas would help diagnose and treat individuals migrating from those areas to Canada and the United States. In this focused review, we first assess the epidemiology of asthma, review known and potential risk factors, and examine commonalities and differences in asthma management across the Americas. We then discuss future directions in research and health policies to improve the prevention, diagnosis, and management of pediatric and adult asthma in the Americas, including standardized and periodic assessment of asthma burden across the region; large-scale longitudinal studies including omics and comprehensive environmental data on racially and ethnically diverse populations; and dissemination and implementation of guidelines for asthma management across the spectrum of disease severity. New initiatives should recognize differences in socioeconomic development and health care systems across the region while paying particular attention to novel or more impactful risk factors for asthma in the Americas, including indoor pollutants such as biomass fuel, tobacco use, infectious agents and the microbiome, and psychosocial stressor and chronic stress.

Keywords: Americas; asthma; risk factors; treatment.

Figure 1.

Pathophysiologic pathways in Th2-high severe asthma. Shown are asthma pathways relevant to currently approved biologics or those being currently evaluated. Reprinted from Reference , under Creative Commons Attribution License (CC BY); original figure created by the authors using Biorender. IgE = immunoglobulin E; IL = interleukin; ILC2 = innate lymphoid cell group 2; PGD₂ = prostaglandin D2; Th2 = T-helper cell type 2; TSLP = thymic stromal lymphopoietin.

Figure 2.

Monoclonal antibodies approved for the treatment of severe asthma across the Americas. Data for the United States obtained from https://www.accessdata.fda.gov/scripts/cder/daf/​index.cfm; for Canada from https://www.canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-product-database.html; and for other countries in the Americas directly from practicing physicians and/or pharmaceutical companies as of August 2021. Map created using https://mapchart.net under CC BY-SA license. BE = benralizumab; DU = dupilumab; ME = mepolizumab; OM = omalizumab; RE = reslizumab.