Duration of day care attendance during infancy predicts asthma at the age of seven: the Cincinnati Childhood Allergy and Air Pollution Study

Clin Exp Allergy. 2014 Oct;44(10):1274-81. doi: 10.1111/cea.12397.

Abstract

Background: Studies vary with respect to the reported effects of day care attendance on childhood asthma.

Objectives: To evaluate the independent and combined effects of day care attendance and respiratory infections on the development of asthma at the age of seven in a prospective birth cohort.

Method: At the age of seven, the study sample included 589 children with complete data of 762 enrolled at birth. Day care hours and number of respiratory infections were reported in follow-up questionnaires through age four. At 7 years of age, asthma was diagnosed in 95 children (16%), based on predefined symptoms criteria confirmed by either asthma FEV1 reversibility after bronchodilator or a positive methacholine test (PC20 ≤ 4 mg/mL). Logistic regression was used to investigate the relationships between asthma at the age of seven, cumulative hours of day care attendance and reported respiratory infections at ages 1-4.

Results: In the univariate analyses, day care attendance at 12 months was associated with an increased risk of asthma [odds ratio (OR) = 1.8, 95% confidence interval (CI) = 1.1-3.0]. Both upper and lower respiratory infections at 12 months also increased the likelihood of asthma [OR = 2.4 (1.4-4.1); OR = 2.3 (1.5-3.7), respectively]. In the final multivariate logistic model, cumulative hours of day care attendance and number of lower respiratory infections at 12 months were associated with asthma [OR = 1.2 (1.1-1.5); OR = 1.4 (1.2-1.7), respectively]. However, a threshold of greater than 37.5 hours per week of day care attendance was associated with a lower risk of asthma [OR = 0.6 (0.4-0.9)].

Conclusion: Depending on duration of attendance, day care during infancy can either increase or reduce risk of asthma at the age of seven.

Keywords: asthma; childhood; daycare; duration; respiratory infections.

MeSH terms

  • Air Pollution / adverse effects*
  • Asthma / etiology*
  • Child
  • Child Day Care Centers*
  • Female
  • Humans
  • Infant
  • Logistic Models
  • Male
  • Respiratory Tract Infections / complications
  • Surveys and Questionnaires
  • Time Factors