Environmental risk factors for persistent asthma in Lucknow.

ABSTRACT

OBJECTIVE: To identify the risk factors for persistent asthma among common environmental exposures, like ambient air pollutants and second hand smoke, animals, place of residence, decreased ventilation, dust, as well as history of allergic conditions like rhinitis, dermatitis and family history of asthma in children. METHODS: This hospital-based, cross-sectional study was conducted after institutional ethical clearance. Children aged 1-12 y with asthma were recruited after parental consent. Children were classified into asthma severity categories according to GINA 2002 and level of control categories according to GINA 2009 guidelines. Adjusted logistic regression analysis was used to identify factors associated with persistent asthma. RESULTS: From August 2008 through October 2010, 205 asthmatic children were recruited of which 73 (35.60 %) had intermittent and 132 (64.40 %) had persistent asthma. Asthma was controlled in 19 (9.26 %), partly controlled in 90 (43.90 %) and uncontrolled in 96 (46.82 %). Patients with persistent asthma were more likely to have uncontrolled asthma (OR = 8.28; 95 % CI 2.43-31.01; p < 0.001). Adjusting for age, sex, socioeconomic status and place of residence, persistent asthma was associated with residence within 1.5 km from heavy traffic (OR = 4.58; 95%CI 2.18-9.59; p < 0.001) and father smoking indoors >5 cigarettes or "bidi"/day (OR = 17.76; 95 % CI 1.85-170.76; p = 0.01). CONCLUSIONS: Since patients with persistent asthma are more likely to have uncontrolled asthma and since persistent asthma is associated with residence closer to heavy traffic and exposure to second hand smoke, minimizing exposures to these may help in better asthma control.