title: Environmental influences on daily emergency admissions in sickle-cell disease patients.
abstract: Previous reports have suggested a role for weather conditions and air pollution on the variability of sickle cell disease (SCD) severity, but large-scale comprehensive epidemiological studies are lacking. In order to evaluate the influence of air pollution and climatic factors on emergency hospital admissions (EHA) in SCD patients, we conducted an 8-year observational retrospective study in 22 French university hospitals in Paris conurbation, using distributed lag non-linear models, a methodology able to flexibly describe simultaneously non-linear and delayed associations, with a multivariable approach. During the 2922 days of the study, there were 17,710 EHA, with a mean daily number of 6.1 ± 2.8. Most environmental factors were significantly correlated to each other. The risk of EHA was significantly associated with higher values of nitrogen dioxide, atmospheric particulate matters, and daily mean wind speed; and with lower values of carbon monoxide, ozone, sulfur dioxide, daily temperature (minimal, maximal, mean, and range), day-to-day mean temperature change, daily bright sunshine, and occurrence of storm. There was a lag effect for 12 of 15 environmental factors influencing hospitalization rate. Multivariate analysis identified carbon monoxide, day-to-day temperature change, and mean wind speed, along with calendar factors (weekend, summer season, and year) as independent factors associated with EHA. In conclusion, most weather conditions and air pollutants assessed were correlated to each other and influenced the rate of EHA in SCD patients. In multivariate analysis, lower carbon monoxide concentrations, day-to-day mean temperature drop and higher wind speed were associated with increased risk of EHA.
authors.affiliation: From the AP-HP, Hôpital H. Mondor - A. Chenevier, Service de Réanimation Médicale, CARMAS research group (AMD, DC, CB-B); Université Paris Est, Faculté de médecine (AMD, DC, FG, CB-B, BM); Inserm, U955, Equipe 8 (AMD, BM); AP-HP, Hôpital H. Mondor - A. Chenevier, Unité de Recherche Clinique (CD-R, AC-N, SK); AP-HP, Hôpital H. Mondor - A. Chenevier, Service d'Information Médicale (FH); AP-HP, Hôpital H. Mondor - A. Chenevier, Unité des Maladies du Globule Rouge (AH, FG); and AP-HP, Hôpital H. Mondor - A. Chenevier, Unité de Pneumologie, Créteil 94000, France (BM); AP-HP, Hôpital Européen Georges Pompidou (SK); Inserm UMRS1138, Centre de Recherche des Cordeliers, Equipe 22, Université Paris Descartes (SK).
authors.forename: Armand
authors.initials: A
authors.lastname: Mekontso Dessap
authors.forename: Damien
authors.initials: D
authors.lastname: Contou
authors.forename: Claire
authors.initials: C
authors.lastname: Dandine-Roulland
authors.forename: François
authors.initials: F
authors.lastname: Hemery
authors.forename: Anoosha
authors.initials: A
authors.lastname: Habibi
authors.forename: Anaïs
authors.initials: A
authors.lastname: Charles-Nelson
authors.forename: Frederic
authors.initials: F
authors.lastname: Galacteros
authors.forename: Christian
authors.initials: C
authors.lastname: Brun-Buisson
authors.forename: Bernard
authors.initials: B
authors.lastname: Maitre
authors.forename: Sandrine
authors.initials: S
authors.lastname: Katsahian
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D000755:Anemia, Sickle Cell / Q000453:epidemiology*; D002248:Carbon Monoxide / Q000032:analysis*; D004636:Emergency Service, Hospital; D006801:Humans; D015999:Multivariate Analysis; D010297:Paris / Q000453:epidemiology; D010343:Patient Admission / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012621:Seasons; D013696:Temperature; D014919:Wind; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D002248:Carbon Monoxide