title: History of respiratory infections in the first 12 yr among children from a birth cohort.
abstract: Respiratory infections are the most frequent health problem in childhood. There is little precise information on how many respiratory illness episodes can be expected in a normal child. This study was designed to create reference values for the frequency of respiratory infections as recordable by history. Respiratory illnesses were recorded in a prospective birth cohort of 1314 German children born in 1990 and tracked until age 12 yr (760 children). Parents recorded the child's illnesses in a diary and answered structured questions yearly up to age 12. Age of study subjects was categorized into infancy (0-2 yr), pre-school age (3-5 yr), and school age (6-12 yr). The mean cumulative number of respiratory infection episodes up to age 12 yr was 21.9 (s.d. 9.0) episodes. In infancy, the mean annual number was 3.4 (3.7) episodes; at pre-school age, 2.3 (2.6) episodes; and at school, age 1.1 (1.2) episodes. The mean cumulative time of episodes up to age 7 yr was 20.1 (15.2) wk. Forty-five percent of the infants in the upper episode incidence tertile continued to be in the upper tertile at school age. Based on a twofold standard deviation of the mean number, up to 11 respiratory infection episodes per year in infancy, 8 episodes per year at pre-school age, and 4 episodes per year at school age could be regarded as normal. Episodes within these reference values per se should not cause unwarranted concern or intervention because of suspected immunodeficiency.
authors.affiliation: Department of Pediatric Pneumology and Immunology, Charité-Universitätsmedizin Berlin, Berlin, Germany. christoph.grueber@charite.de
authors.forename: Christoph
authors.initials: C
authors.lastname: Grüber
authors.forename: Thomas
authors.initials: T
authors.lastname: Keil
authors.forename: Michael
authors.initials: M
authors.lastname: Kulig
authors.forename: Stephanie
authors.initials: S
authors.lastname: Roll
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wahn
authors.forename: Volker
authors.initials: V
authors.lastname: Wahn
mesh_terms: D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003139:Common Cold / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D012141:Respiratory Tract Infections / Q000453:epidemiology*; D012307:Risk Factors; D012621:Seasons; D011795:Surveys and Questionnaires
chemical_list: D007073:Immunoglobulin E