Impact of exposure of emergency patients with acute heart failure to atmospheric Saharan desert dust.

OBJECTIVES: To explore whether episodes of exposure to atmospheric Saharan dust is a risk factor for hospitalization in patients with acute heart failure (AHF) attended in a hospital emergency department (ED).

METHODS: Single-center retrospective study of patients with AHF. The cohort was analyzed in 2 groups: ED patients hospitalized with AHF and patients discharged home from the ED. Air pollution on the 5 days leading to ED admission for AHF was recorded as the average concentration of breathable particulate matter with an aerodynamic diameter of no more than 10 µm (PM10) in the following ranges: fine PM (diameter less than 2.5 µm) or coarse PM (diameters between 2.5 and 10 µm). High Saharan dust pollution exposure was defined by mean daily PM10 concentrations between 50 and 200 µg/m3. Multivariable analysis was used to estimate risk for AHF in relation to PM10 exposure in the 5 days before the ED visit.

RESULTS: A total of 1097 patients with AHF were treated in the ED; 318 of them (29%) were hospitalized and 779 (71%) were discharged home. Hospitalized patients were older, had more concomitant illnesses, and more episodes of exposure to Saharan dust (P < .0001). Multivariable analysis confirmed the association between Saharan dust exposure and hospital admission in these patients (odds ratio, 2.36; 95% CI, 1.21-4.58; P = .01).

CONCLUSION: In the absence of prospective studies, the results of this series suggest that exposure to high levels of Saharan dust (PM10 concentrations between 50 and 200 µg/m3) may be a precipitating factor for hospitalization in AHF episodes.