Passive Smoking, Inflammatory Markers and Childhood Asthma

Children from 0 to 4 years have the highest hospitalization and prevalence rates in the U.S. Smoking during pregnancy has been implicated as a risk factor for childhood asthma and may affect severity. One of the great challenges in pediatric respiratory medicine is to identify early stages of asthma during the first years of life. Serum eosinophilic cationic protein (ECP) and urinary eosinophilic protein X (EPX) have the potential for a medical breakthrough in the diagnosis of asthma in children. Serum ECP is associated with asthma activity, anti-inflammatory treatment, atopy, and environmental tobacco smoke (ETS), whereas uEPX increases with wheeze/asthma, decreasing age, and eczema. Remarkably, sECP and uEPX and the role of ETS have never been investigated in young children. We hypothesize that sECP and/or uEPX may be valuable measures of eosinophil activation in young asthmatics, particularly those exposed to ETS during pregnancy and postnatally (via breast-feeding). A prospective study is being conducted to recruit approximately 140 Caucasian, African-American, Hispanic, and Asian children (0-4 years), newly diagnosed with asthma at hospitals in Southern California. A comparison group of 140 controls, matched on age, race, sex, and hospital are also being recruited from pediatrics clinics. All parents complete a detailed telephone interview, 2 follow-up questionnaires, and a diary on asthma symptoms. Infants also provide urine and serum at baseline, and every 4 months, for one year. SECP and uEPX may be predictors of future asthma development and severity, and permit differentiation of susceptible infants exposed to ETS in utero/postnatally.