Environmental Intervention Versus Standard Care to Reduce Pharmacologic Therapy for Asthma

Overview

Exposure to household allergens is a major contributor to asthma symptoms. Aggressive measures to reduce household allergens has the potential to reduce asthma symptoms and the need for medications to control asthma. The investigators plan to enroll patients aged 6 and above into a single blind, randomized study comparing intensive environmental intervention with usual asthma care over a 48 week study period. All subjects will have asthma treatment optimized according to guideline based care. Subjects will be randomized to an aggressive environmental remediation arm versus distribution of written materials regarding allergen reduction ("usual care"). Primary outcome measure will be ability to reduce asthma step therapy. Secondary outcomes include measures of lung function, asthma biomarkers and quality of life.

Research question(s): In individuals with atopic asthma who are being treated with inhaled corticosteroids with or without long acting beta agonists (1 of 6 possible steps of treatment), aggressive environmental intervention to reduce exposure to home allergens is more likely to lead to one step reduction in asthma controller therapy, improved asthma control and improved biomarkers of airway inflammation than is usual care. Scientific abstract: Environmental exposure to indoor allergens is a major contributor to asthma impairment and risk, particularly among asthmatic patients residing in inner cities. The investigators plan a randomized controlled trial to assess the effect of individualized, comprehensive, multifaceted indoor allergen avoidance measures on ability to step down asthma controller therapy in adults and children greater than 6 years with mild to severe persistent asthma. Specifically, 1\. To determine via a randomized, controlled trial in allergen sensitized asthma patients whether environmental intervention aimed at reducing exposure to indoor allergens and irritants is more effective in reducing National Asthma Education and Prevention Program (NAEPP) step based therapy than usual care over a 48 week study period. 2a. To determine if environmental intervention leads to reduction in indoor allergen levels, allergen specific serum IgE levels, airway hyper-responsiveness, fractional excretion of nitric oxide, asthma symptom score, asthma exacerbations, treatment failures and improved lung function compared to usual care over a 48 week study period. 2b. (Exploratory): To determine if there is an association between reduction in allergen specific IgE level and reduction in NAEPP step level required for asthma control among subjects randomized to environmental intervention compared with usual care.