title: Secondhand smoke exposure is associated with proteinuria in children with chronic kidney disease.
abstract: BACKGROUND
  In adults with chronic kidney disease (CKD), cigarette smoking is associated with an increased risk for CKD progression and transplant failure. In children, secondhand smoke (SHS) exposure has been associated with elevated blood pressure. There are no studies on the prevalence and effect of SHS exposure in CKD.
  
  
  METHODS
  Subjects were enrolled in the Chronic Kidney Disease in Children (CKiD) Study, an observational cohort of 366 children aged 1 to 16 years with CKD. Secondhand smoke exposure was obtained via questionnaire. SHS exposure was also determined based on urine cotinine (Ucot) measurements (1 ng/mL ≤ Ucot < 75 ng/mL). The cross-sectional association of SHS exposure with proteinuria was assessed.
  
  
  RESULTS
  Using Ucot, 22 % of subjects were exposed to SHS. SHS exposure was significantly associated with lower maternal education and African American race, and a greater prevalence of nephrotic range proteinuria and left ventricular hypertrophy. In a multivariate model (including sex, age, race, maternal education, income level, private insurance status, abnormal birth history and CKD diagnosis), the prevalence odds of nephrotic range proteinuria was 2.64, (95 % confidence interval 1.08, 6.42) higher in children exposed to SHS compared to those unexposed.
  
  
  CONCLUSIONS
  In our cohort of children with CKD, SHS exposure was common (22 %) and independently associated with nephrotic range proteinuria. Exposure to SHS may be an important factor to consider in CKD progression.
authors.affiliation: Department of Pediatrics, Wright State University, One Children's Plaza, Dayton, OH 45404, USA. omolojaa@childrensdayton.org
authors.forename: Abiodun
authors.initials: A
authors.lastname: Omoloja
authors.forename: Judith
authors.initials: J
authors.lastname: Jerry-Fluker
authors.forename: Derek K
authors.initials: DK
authors.lastname: Ng
authors.forename: Alison G
authors.initials: AG
authors.lastname: Abraham
authors.forename: Susan
authors.initials: S
authors.lastname: Furth
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Warady
authors.forename: Mark
authors.initials: M
authors.lastname: Mitsnefes
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000652:urine; D002648:Child; D002675:Child, Preschool; D003367:Cotinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000453:epidemiology; D007223:Infant; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009401:Nephrosis / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence; D011507:Proteinuria / Q000175:diagnosis / Q000453:epidemiology*; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000453:epidemiology*; D012307:Risk Factors; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D003367:Cotinine