[Tobacco, infant feeding, and wheezing in the first three years of life].

BACKGROUND

Wheezing lower respiratory tract diseases are frequent and troublesome in young children. However, the only avoidable risk factors for them are tobacco smoke exposure and feeding practices.

OBJECTIVE

To measure the influence of these avoidable factors on the risk of wheeze in the first 3 years of life.

METHODS

We performed a population study including all the children born between January 1998 and November 2002 who were attended in the same primary health center in Palencia (Spain) from birth. Information on family history, pregnancy, delivery, and smoking was obtained soon after birth. Feeding practices were recorded on monthly visits. Wheezing episodes in the first 3 years of life were identified by a pediatrician.

RESULTS

Two hundred thirty-four children were included and 43 had at least one episode of wheezing. The results were adjusted by sex, prematurity, a family history of allergy, having older siblings, maternal age, and month of birth. No association was found between wheezing and exclusive breast feeding for 3 months (hazard ratio [HR] 5 0.83, 95 % CI: 0.42-1.64), or with postnatal exposure to tobacco smoke (HR 5 1.2, 95 % CI: 0.45-2.34). Tobacco smoke exposure during pregnancy was associated with a higher risk of wheezing: HR 5 2.54 (95 % CI: 1.18-5.48).

CONCLUSIONS

Prenatal exposure to tobacco smoke is the main modifiable risk factor for wheezing diseases in the first 3 years of life.