TY - JOUR T1 - The effects of current regular smoking on asthma subtypes in the Northern Finnish asthma study JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2015.PA1112 VL - 46 IS - suppl 59 SP - PA1112 AU - Elina Mäkikyrö AU - Maritta Jaakkola AU - Jouni Jaakkola Y1 - 2015/09/01 UR - http://erj.ersjournals.com/content/46/suppl_59/PA1112.abstract N2 - Background: There are only few studies on subtypes of asthma among adult asthmatics based on clustering methods. Even fewer studies elaborated the effects of current smoking on asthma subtypes defined by variables of asthma control.Objectives: We investigated statistically the subtypes of asthma among 1995 17-73 year-old asthmatics from the Northern Finnish Asthma Study. We also investigated the effects of current regular smoking (N = 272) on these subtypes.Methods: Latent class analysis was used and variables included were inhaled (ICS) and oral corticosteroid (OCS) use, antibiotics due to asthma exacerbations (AB), acute health care use and sick leave due to asthma within the last 12 months and symptom (SYM) and impact scores (IMP) from the St George's Respiratory Questionnaire. The odds ratios and 95% confidence intervals (CI) of membership probabilities were calculated for current regular smoking. Sex and age were used as covariates (ORa).Results: The best fitting model had 4 groups defined as Mild, Moderate, Severe and Poorly controlled asthma. The group membership probabilities were 39% for Mild, 14% for Moderate, 13% for Severe and 34% for Poorly controlled asthma. SYM and IMP were high in the Poorly controlled and Severe asthma, but those in the first used less OCS, daily ICS and AB. Current regular smoking increased the risk of belonging to a more difficult asthma subtype. The ORas and CIs for the different groups with Mild as the reference were Moderate 1.77 (1.00-3.13), Severe 2.41 (1.44-4.04) and Poorly controlled 3.56 (2.35-5.40).Conclusions: Smoking is an important determinant of asthma control. Smokers seem to be less compliant to treatment and have more severe disease. ER -