title: Serum level of vitamin D and trace elements in children with recurrent wheezing: a cross-sectional study.
abstract: BACKGROUND
  We aimed to show the relationship between recurrence of wheezing and serum levels of vitamin D, zinc, and copper in wheezy children compared with a healthy group.
  
  
  METHODS
  In this cross sectional study, seventy-three children with wheezing and seventy-five controls were included without a follow-up period. The clinical characteristics of the children were assessed, the asthma predictive index and temporal pattern of wheeze were determined. The serum levels of vitamin D, zinc, and copper were measured. Pearson correlation analysis was used to evaluate the relationship between homogeneously distributed variables.
  
  
  RESULTS
  Thirty-two of the seventy-three children (43.8%) had more than three wheezing attacks (recurrent wheezing). The Asthma Predictive Index index was positive in 26 patients (35.6%). When classified to temporal pattern of wheeze, fifty-three of the study group (72.6%) had episodic wheezing and the remainder (27.4%) was classified as multiple-trigger wheezing. We found no overall significant difference between the study and control group in terms of vitamin D and trace elements . The vitamin D and zinc levels were significantly lower and serum copper and copper/zinc ratio was significantly higher in patients with recurrent wheezing (p =0.03, p <0.01, p =0.013, p <0.01, respectively) positive Asthma Predictive Index and multiple-trigger temporal pattern of wheeze compared with patients with non- recurrent wheezing, negative Asthma Predictive Index and episodic temporal pattern of wheeze.
  
  
  CONCLUSIONS
  It may be postulated that for the determination of asthma risk in patients with recurrent wheezing, the serum level of vitamin D, copper and zinc can be used as a routine biomarker alongside the Asthma Predictive Index and temporal pattern of wheeze.
authors.affiliation: Department of Pediatrics, Istanbul University, Istanbul Faculty of Medicine, Capa, 34390 Istanbul, Turkey. metin.uysalol@gmail.com.
authors.forename: Metin
authors.initials: M
authors.lastname: Uysalol
authors.forename: Ezgi Pasli
authors.initials: EP
authors.lastname: Uysalol
authors.forename: Yasin
authors.initials: Y
authors.lastname: Yilmaz
authors.forename: Gunes
authors.initials: G
authors.lastname: Parlakgul
authors.forename: Tulin Ayse
authors.initials: TA
authors.lastname: Ozden
authors.forename: Hayriye Vehid
authors.initials: HV
authors.lastname: Ertem
authors.forename: Beyhan
authors.initials: B
authors.lastname: Omer
authors.forename: Nedret
authors.initials: N
authors.lastname: Uzel
mesh_terms: D001249:Asthma / Q000097:blood; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003300:Copper / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D012008:Recurrence; D012135:Respiratory Sounds; D012136:Respiratory Syncytial Viruses / Q000302:isolation & purification; D012229:Rhinovirus / Q000302:isolation & purification; D018570:Risk Assessment; D014807:Vitamin D / Q000097:blood*; D015032:Zinc / Q000097:blood*
chemical_list: D015415:Biomarkers; D014807:Vitamin D; D003300:Copper; D015032:Zinc