Risk factors for wheezing in primary school children in Bursa, Turkey

Wheezing is the most common symptom of childhood respiratory tract illnesses. It is important not only for its associated acute morbidity, but also for the fact that early childhood wheezing confers a high risk for asthma. Epidemiological studies from various countries show that 10-15% of children <1 year of age and 25% of children <5 years of age have wheezing-associated respiratory tract illness, and one-third of these children develop asthma later in life.

In this retrospective study, we evaluated the association between a history of wheezing and prenatal, postnatal, familial, and environmental risk factors in 858 7-year-old children, randomly selected from seven primary schools in Bursa, Turkey, by means of an easy-to-understand questionnaire form. Among these children, 12.4% had a history of early transient wheezing, 7.1% had persistent wheezing, and 7.7% had late onset wheezing; 72.8% had no wheezing symptoms and 33.3% of children who experienced wheezing during the first 3 years of life had physician-diagnosed asthma.

Notable risk factors associated with wheezing were as follows: male gender, lower socioeconomic status, premature birth, maternal smoking during pregnancy, bottle-feeding before 2 months of age, dampness and mold at home, hospitalization due to any respiratory illness in infancy, history of croup between 6 months and 5 years of age, frequent upper respiratory infections during the first 3 years of life, allergic eczema in the child, and any allergic disease in the mother or siblings.

This study shows that the high rates of reported wheezing in the 858 primary school children in Bursa are clearly attributable to important risk factors that have long been recognized and discussed by researchers worldwide, and this suggests that all efforts at primary prevention may be insufficient.