Aim: To determine whether parental smoking increased the risk of hospitalization among children aged less than 2 years.
Design: Case-reference study conducted from April 1995-May 1996. The group of cases was composed of 40% of all the children aged 2 years or less years admitted to our hospital (n=392). The reference population was composed of 15% of the live newborns in the same the hospital (n=493). The information was obtained by face-to-face interview after delivery in both populations and by telephone interview or postal survey and was completed in the reference population one year after delivery.
Results: Maternal smoking increased the risk of hospitalization for lower respiratory illness (adjusted RR - 1.79; 95% CI = 1.03-3.11). Moreover, the risk of hospitalization for upper or lower respiratory illness, lower respiratory illness and bronchiolitis was increased when the mother smoked more than 19 cigarettes per day. The results were adjusted for confounding factors such as prenatal age, ethnic group, maternal education, social class, breastfeeding and hospitalization of the newborn. Parental smoking, specifically maternal smoking, affects children's health, increasing the risk of hospitalization for respiratory illness in the first 2 years of life.