title: Indoor exposure to particulate matter and age at first acute lower respiratory infection in a low-income urban community in Bangladesh.
abstract: The timing of a child's first acute lower respiratory infection (ALRI) is important, because the younger a child is when he or she experiences ALRI, the greater the risk of death. Indoor exposure to particulate matter less than or equal to 2.5 µm in diameter (PM2.5) has been associated with increased frequency of ALRI, but little is known about how it may affect the timing of a child's first ALRI. In this study, we aimed to estimate the association between a child's age at first ALRI and indoor exposure to PM2.5 in a low-income community in Dhaka, Bangladesh. We followed 257 children from birth through age 2 years to record their age at first ALRI. Between May 2009 and April 2010, we also measured indoor concentrations of PM2.5 in children's homes. We used generalized gamma distribution models to estimate the relative age at first ALRI associated with the mean number of hours in which PM2.5 concentrations exceeded 100 µg/m(3). Each hour in which PM2.5 levels exceeded 100 µg/m(3) was independently associated with a 12% decrease (95% confidence interval: 2, 21; P = 0.021) in age at first ALRI. Interventions to reduce indoor exposure to PM2.5 could increase the ages at which children experience their first ALRI in this urban community.
authors.forename: Emily S
authors.initials: ES
authors.lastname: Gurley
authors.forename: Henrik
authors.initials: H
authors.lastname: Salje
authors.forename: Nusrat
authors.initials: N
authors.lastname: Homaira
authors.forename: Pavani K
authors.initials: PK
authors.lastname: Ram
authors.forename: Rashidul
authors.initials: R
authors.lastname: Haque
authors.forename: William A
authors.initials: WA
authors.lastname: Petri
authors.forename: Joseph
authors.initials: J
authors.lastname: Bresee
authors.forename: William J
authors.initials: WJ
authors.lastname: Moss
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Luby
authors.forename: Patrick
authors.initials: P
authors.lastname: Breysse
authors.forename: Eduardo
authors.initials: E
authors.lastname: Azziz-Baumgartner
mesh_terms: D000208:Acute Disease; D000367:Age Factors; D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D016902:Air Pollution, Indoor / Q000009:adverse effects* / Q000032:analysis; D001459:Bangladesh; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019570:Inhalation Exposure / Q000009:adverse effects* / Q000032:analysis; D053208:Kaplan-Meier Estimate; D008297:Male; D015233:Models, Statistical; D015999:Multivariate Analysis; D052638:Particulate Matter / Q000009:adverse effects* / Q000032:analysis; D011203:Poverty; D012141:Respiratory Tract Infections / Q000209:etiology*; D012307:Risk Factors; D014504:Urban Health
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Bangladesh; acute lower respiratory infection; child health; particulate matter; survival analysis