Daycare attendance, asthma and atopy

The objective of this article is to review studies that have examined the r elation of daycare to asthma and atopy. In order to identify studies for in clusion, abstracts of all studies referenced in Medline from January 1966 t o January 2000 and in BIBSYS were searched and extracted if they included ' asthma' or 'atopy' combined with words such as 'daycare', 'nursery' or 'kin dergarten'. Eight studies fulfilled the criteria of inclusion. The outcomes were asthma, skin prick test (SPT) reactivity, a positive radioallergosorb ent test (RAST), hay fever, and eczema. Daycare attendance was positively a ssociated with asthma in five of six studies including asthma. In three of these studies there was no statistically significant association between da ycare and asthma. Early start in daycare protected against later asthma in one study There was a weak, but nor a statistically significant positive re lation between daycare and atopy in two of three studies when SPT reactivit y was used as the outcome. In children of small families early start in day care protected against atopy. The quality of the studies varies, and they a re not directly comparable. The relation between daycare attendance and ast hma and atopy is unclear, and further studies designed to answer this speci fic research question are needed.