Table 3.

Contacts With Other Children and Parental History of Allergic Disease and Other Factors in Relation to Respiratory Tract Infections in the First 12 Months of Life

URTILRTI
AOR*95% CIAOR*95% CI
No child care11
Child care, small group1.41.2–1.72.01.5–2.6
Child care, large group2.72.1–3.44.83.5–6.9
Siblings1.21.0–1.52.51.9–3.1
No parent allergic11
Only mother allergic1.10.8–1.51.20.8–1.8
Only father allergic1.00.8–1.21.20.9–1.6
Both parents allergic1.20.8–1.71.61.0–2.5
Maternal smoking during pregnancy
 No smoking11
 Only smoking first trimester1.30.9–1.91.50.9–2.8
 Smoking whole pregnancy1.00.7–1.21.30.9–1.7
Male gender1.00.8–1.11.41.1–1.7
Maternal age (for each additional year)0.970.95–1.000.930.90–0.96
Season of birth
 Winter11
 Spring0.90.7–1.20.90.7–1.3
 Summer0.90.7–1.20.90.7–1.3
 Fall0.80.6–1.00.80.6–1.2
Type of feeding at 3 mo
 Exclusive breastfeeding11
 Breastfeeding and formula1.41.1–1.81.00.7–1.5
 Exclusive formula1.61.3–1.91.51.1–1.9
Low level of parental education1.41.0–2.00.80.5–1.3
  • *  Adjusted for type of study, employment of the mother, and the other risk factors, eg, results for siblings are adjusted for child care attendance, parental history of allergic disease, maternal smoking during pregnancy, gender, maternal age, season of birth, type of feeding, level of parental education.

  •  OR adjusted like above* and also adjusted for birth weight and duration of pregnancy.