The aim of this study was to evaluate the effect of smoking on lung function decline in adult-onset asthma in a clinical, 12-year follow-up study.In the Seinäjoki Adult Asthma Study, 203 patients were followed for 12 years (1999-2013) after diagnosis of new-onset adult asthma. Patients were divided into two groups based on smoking history: <10 or ≥10 pack-years. Spirometry evaluation points were: 1) baseline, 2) the maximum lung function during the first 2.5 years after diagnosis (Max) and 3) after 12 years of follow-up.Between Max and follow-up, the median annual decline in absolute forced expiratory volume in 1 s (FEV) was 36 mL in the group of patients with <10 pack-years of smoking and 54 mL in those with smoking history ≥10 pack-years (p=0.003). The annual declines in FEV % pred (p=0.006), forced vital capacity (FVC) (p=0.035) and FEV/FVC (p=0.045) were also accelerated in the group of patients with ≥10 pack-years smoked. In multivariate regression analysis, smoking history ≥10 pack-years became a significant predictor of accelerated decline in FEVAmong patients with clinically defined adult-onset asthma, smoking history ≥10 pack-years is associated with accelerated loss of lung function.

Results can be used to predict outcomes of patients with adult-onset asthma and to aid in development of personalized therapy (NCT02733016 at ClinicalTrials.gov).

Differences between asthma-COPD overlap syndrome (ACOS) and adult-onset asthma are poorly understood. This study aimed to evaluate these differences in a clinical cohort of patients with adult-onset asthma, as a part of the Seinäjoki Adult Asthma Study (SAAS).188 patients were diagnosed with adult-onset asthma and re-evaluated 12 years after diagnosis. They were divided into three groups based on smoking history and post bronchodilator spirometry values: 1) never- and ex-smokers with <10 smoked pack-years; 2) non-obstructive (forced expiratory volume in 1 s (FEV)/forced vital capacity (FVC) ≥0.7) patients with ≥10 pack-years; and 3) ACOS patients with ≥10 pack-years and FEV/FVC <0.7.ACOS patients had lower diffusing capacity (/V 86% predicted 98 or 96% predicted; p<0.001), higher blood neutrophil levels (4.50 3.60 or 3.85×10 L; p=0.008), and higher IL-6 levels (2.88 1.52 or 2.10 pg·mL, p<0.001) as compared to never- and ex-smokers with <10 pack-years, or non-obstructive patients with ≥10 pack-years smoking history, respectively. ACOS patients also showed reduced lung function, higher remaining bronchial reversibility and a higher number of comorbidities.This study shows distinct differences in diffusing capacity, blood neutrophil and IL-6 levels, bronchial reversibility, lung function and comorbidities between ACOS and adult-onset asthma. The present findings should be considered in the comprehensive assessment of adult asthma patients.

Background: There is a lack of knowledge on the association between daily physical activity and lung function in patients with asthma. Objective: This study aims to examine the association between daily physical activity and asthma control, lung function, and lung function decline in patients with adult-onset asthma. Design: This study is part of Seinäjoki Adult Asthma Study (SAAS), where 201 patients were followed for 12 years after asthma diagnosis. Daily physical activity was assessed at follow-up by a structured questionnaire and used to classify the population into subgroups of low (≤240 min) or high (>240 min) physical activity. Three spirometry evaluation points were used: 1. diagnosis, 2. the maximum lung function during the first 2.5 years after diagnosis (Max0-2.5), 3. follow-up at 12 years. Results: High physical activity group had slower annual FEV1 (p<0.001) and FVC (p<0.018) decline. Additionally, the high physical activity group had higher FEV1 values at follow-up, and higher FEV1/FVC ratios at follow-up and diagnosis. There was no difference in BMI, smoking, medication, or frequency of physical exercise between high and low physical activity groups. Differences remained significant after adjustments for possible confounding factors. Conclusion: This is the first demonstration of an association between long-term FEV1 decline and daily physical activity in clinical asthma. Low physical activity is independently associated with faster decline in lung function. Daily physical activity should be recommended in treatment guidelines in asthma.

Adherence to inhaled corticosteroids (ICS) has been suggested to be poor but long-term follow-ups are lacking. The objective of the present study was to assess adherence to ICS treatment in patients with adult-onset asthma during 12-year follow-up.A total of 181 patients with clinically confirmed, new-onset adult asthma were followed for 12 years as part of the Seinäjoki Adult Asthma Study. Adherence to ICS was assessed individually as the percentage of true dispensed ICS in micrograms per true prescribed daily ICS in micrograms over 12 years.Mean 12-year adherence to ICS was 69% (mean±sd dispensed 2.5±1.8 g and prescribed 3.6±1.5 g budesonide equivalent per patient for 12 years), annual adherence varying between 81% (year 1) and 67% (year 12). Patients with good 12-year adherence (≥80%) used oral corticosteroids more often, and had add-on drugs in use and asthma-related visits to healthcare more often. In addition, they showed less reversibility in forced expiratory volume in 1 s and had higher peripheral blood neutrophil counts. However, lung function decline was steeper in patients with poorer adherence (<80%) and this association remained in multiple linear regression analysis. No difference was found in symptom scores, blood eosinophil counts, exhaled nitric oxide or immunoglobulin E between the patients with different levels of adherence.In patients with adult-onset asthma, adherence to ICS was moderate. Poorer adherence (<80%) to ICS was associated with more rapid decline in lung function but was not associated to symptoms or markers of inflammatory endotypes.