Day-care center attendance and risk of Asthma-A systematic review

Asthma and other wheezing disorders are common chronic health problems in childhood. We aim to evaluate whether the attendance by children under three years of age to day-care centers is a protector or risk factor in the development of recurrent wheezing or asthma in the following years of their lives.

Systematic review of published cohort or cross-sectional studies, without any time limitation. We searched in PubMed, Cinhal, Cuiden and Scopus (EMBASE included). The quality of the studies was evaluated using the Newcastle-Ottawa Scale. Disagreements were solved by mutual consensus. Weighted odds ratio (ORs) were estimated using RevMan 5.3, following random effects models.

We selected 18 studies for qualitative analysis, nine cohort studies and nine cross-sectional studies. Day-care center attendance is associated with an increased risk of early recurrent wheezing (four studies; 50,619 subjects; adjusted OR 1.87 [1.21 to 2.88]; I² 91%) and asthma before the age of six (five studies; 5412 subjects; adjusted OR 1.59 [1.26 to 2.01]; I² 0%), but not later (five studies; 5538 subjects; adjusted OR 0.86 [0.55 to 1.32]; I² 76%).

Children attending day-care center during the first years of life have a higher risk of recurrent wheezing during the first three years and asthma before the age of six, but not later. This risk must be taken into account to inform parents in order to choose what kind of care children should have throughout infancy and to implement preventive measures to reduce its impact.