TY - JOUR T1 - Seasonal variations in asthma attacks and grass sensitisation JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - 3226 AU - Cristina Canova AU - Peter Burney AU - Deborah Jarvis Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/3226.abstract N2 - Seasonal variation in asthma mortality and hospitalization has been reported. In this study we describe seasonal variation in asthma symptoms and assess whether this was modified by SPT sensitisation. Asthmatics aged 20-44 years (n=2573) taking part in the European Community Respiratory Health Survey I are included.Participants identified bi-monthly periods they usually experienced attacks of asthma. Effect modification of sensitization to grass, cat, dust, birch, Alternaria on asthma attacks in each bi-monthly period was assessed within each country, using marginal logistic regressions, based on generalised estimating equations. Interaction coefficients were then combined using random effects meta-analysis.Seasonal variation in asthma attacks was seen in most countries, although with different patterns. Seasonal variation was not modified by sensitisation to indoor allergens (cat, dust) but was modified by sensitisation to grass.In Southern Europe the risk of asthma in May/June compared to Jan/Feb in those with IgE to grass was six times that seen in asthmatics not sensitised to grass. Overall sensitisation to Alternaria increased the risk of attacks in Jul/Aug compared to Jan/Feb (OR 2.3).Asthmatics sensitised to grass and Alternaria experience seasonal exacerbations likely triggered by allergen exposure. The effect of pollen on asthma severity in a sub group of susceptible asthmatics may be much greater than previously documented. ER -