Association between African Dust Transport and Acute Exacerbations of COPD in Miami

Abstract

Background: Air pollution is increasingly recognized as a risk factor for acute exacerbation of chronic obstructive pulmonary disease (COPD). Changing climate and weather patterns can modify the levels and types of air pollutants. For example, dust outbreaks increase particulate air pollution. Objective: This paper examines the effect of Saharan dust storms on the concentration of coarse particulate matter in Miami, and its association with the risk of acute exacerbation of COPD (AECOPD). Methods: In this prospective cohort study, 296 COPD patients (with 313 events) were followed between 2013 and 2016. We used Light Detection and Ranging (LIDAR) and satellite-based Aerosol Optical Depth (AOD) to identify dust events and quantify particulate matter (PM) exposure, respectively. Exacerbation events were modeled with respect to location- and time-lagged dust and PM exposures, using multivariate logistic regressions. Measurements and main results: Dust duration and intensity increased yearly during the study period. During dust events, AOD increased by 51% and particulate matter ≤2.5 µm in aerodynamic diameter (PM2.5) increased by 25%. Adjusting for confounders, ambient temperature and local PM2.5 exposure, one-day lagged dust exposure was associated with 4.9 times higher odds of two or more (2+ hereto after) AECOPD events (odds ratio = 4.9; 95% CI = 1.8–13.4; p < 0.001). Ambient temperature exposure also showed a significant association with 2+ and 3+ AECOPD events. The risk of AECOPD lasted up to 15 days after dust exposure, declining from 10× higher on day 0 to 20% higher on day 15. Conclusions: Saharan dust outbreaks observed in Miami elevate the concentration of PM and increase the risk of AECOPD in COPD patients with recurring exacerbations.

Climate change and global issues in allergy and immunology

“…93 Several studies have reported significant associations between exposure to Saharan dust and hospital admissions due to asthma, COPD exacerbations, and cardiovascular and cerebrovascular conditions. [94][95][96] In addition, Saharan dust storms have been linked with mortality due to respiratory diseases and severe cardiovascular and ischemic events among vulnerable populations. 91,94,96,97 In West Africa, exposure to these dust storms has been associated with increased infant mortality.…”

Dust from the Sahara to the American Continent: Health impacts

“…López-Villarrubia et al 40 saw shreds of evidence of an increased risk for hospital admissions because of asthma and COPD in patients exposed to SahD in the Canary Islands. Gutierrez et al 61 studied the same phenomenon in Miami and documented an increased risk for recurrent acute exacerbations in patients with COPD and PM. 61 Exposure to high concentrations of PM 10 because of SahD transport events is associated with an intense inflammatory reaction in the airway mucosa of patients with ischemic heart disease.…”

“…Gutierrez et al 61 studied the same phenomenon in Miami and documented an increased risk for recurrent acute exacerbations in patients with COPD and PM. 61 Exposure to high concentrations of PM 10 because of SahD transport events is associated with an intense inflammatory reaction in the airway mucosa of patients with ischemic heart disease. 10 Areas affected by desert sandstorms, such as Caribbean communities, are known to have some of the highest incidences of asthma on the planet.…”

Long‐term exposure to indoor air pollution and risk of tuberculosis

“…However, outdoor particulate matter 2.5 ≤ µm in aerodynamic diameter (PM 2.5 ) was estimated using a hybrid approach, which has been used for deriving PM 2.5 estimates in different parts of the world including Delhi Metropolitan. [44][45][46][47] Satellite-based aerosol optical depth (AOD) from MODerate resolution Imaging Spectroradiometer (MODIS) onboard Terra and Aqua satellite at 3-km spatial resolution were acquired from NASA from 2002 to 2009 for the study area. 48 These data were collocated with the meteorological data.…”