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Background: Child-onset asthma is known to remit with high probability but remission in adult-onset asthma seems to be less common. Reports of association between remission and asthma onset age in adulthood are scarce. Objectives: To study if age at asthma diagnosis and gender are associated to remission rate in adult asthma population. Methods: In 2016, a random sample of 16 000 subjects aged 20-69 years from Helsinki and Western Finland were sent a FinEsS-questionnaire. Asthma was categorized by reported age when diagnosed with asthma by a physician: child (0-11 years) adolescent-young-adult (12-39 years) and late-adult-diagnosed (40-69 years). Remission was defined as a physician diagnosed asthma but not having had asthma symptoms, wheezing or use of asthma medication in the past 12 months. Results: 8199 subjects (51.5%) responded to the postal questionnaire. Remission was most common in child-diagnosed (30.2%), followed by adolescent-young-adult-diagnosed (17.9%) and least common in late-adult-diagnosed asthma (5.0%) (p<0.001). In males, the corresponding proportions were 36.7%, 20.0% and 3.4%, and in females 20.4%, 16.6% and 5.9%, respectively (p<0.001 for gender difference). In binary logistic regression, significant risk factors of non-remission were diagnosis at adolescent-young-adulthood- (OR=2.2, 95% CI 1.4-3.4) or late-adulthood- (OR=11.1, 4.8-25.4), asthma-COPD overlap (ACO) (OR=5.6, 1.3-24.5), allergic rhinitis (OR=2.3, 1.5-3.5) and family history of asthma (OR=1.9, 1.2-2.8). Results remained similar after exclusion of ACO. Conclusion: Remission was rare (5%) in adults diagnosed with asthma after age 40 years in both sexes. Causes of poor prognosis in adult-onset asthma need to be further elucidated.

Background: Attempts have been made to use dynamic spirometry to define restrictive lung function, but the definition of a restrictive spirometric pattern (RSP) varies between studies such as BOLD and NHANES. The aim of this study was to estimate the prevalence and risk factors of RSP among adults in northern Sweden based on different definitions. Methods: In 2008-2009 a general population sample aged 21-86y within the obstructive lung disease in northern Sweden (OLIN) studies was examined by structured interview and spirometry, and 726 subjects participated (71% of invited). The prevalence of RSP was calculated according to three different definitions based on pre-as well as post-bronchodilator spirometry: 1) FVC <80% & FEV1/FVC > 0.7 2) FVC <80% & FEV1/FVC > LLN 3) FVC LLN Results: The three definitions yielded RSP prevalence estimates of 10.5%, 11.2% and 9.4% respectively, when based on pre-bronchodilator values. The prevalence was lower when based on post-bronchodilator values, i.e. 7.3%, 7.9% and 6.6%. According to definition 1 and 2, the RSP prevalence increased by age, but not according to definition 3. The overlap between the definitions was substantial. When corrected for confounding factors, manual work in industry and diabetes with obesity were independently associated with an increased risk for RSP regardless of definition. Conclusions: The prevalence of RSP was 7-11%. The prevalence estimates differed more depending on the choice of pre-compared to post-bronchodilator values than on the choice of RSP definition. RSP was, regardless of definition, independently associated with manual work in industry and diabetes with obesity. (C) 2016 The Authors. Published by Elsevier Ltd.

Background: Reduced lung function in patients with chronic obstructive pulmonary disease (COPD) is likely due to both environmental and genetic factors. We report here a targeted high-throughput DNA sequencing approach to identify new and previously known genetic variants in a set of candidate genes for COPD. Methods: Exons in 22 genes implicated in lung development as well as 61 genes and 10 genomic regions previously associated with COPD were sequenced using individual DNA samples from 68 cases with moderate or severe COPD and 66 controls matched for age, gender and smoking. Cases and controls were selected from the Obstructive Lung Disease in Northern Sweden (OLIN) studies. Results: In total, 37 genetic variants showed association with COPD (p <0.05, uncorrected). Several variants previously discovered to be associated with COPD from genetic genome-wide analysis studies were replicated using our sample. Two high-risk variants were followed-up for functional characterization in a large eQTL mapping study of 1,111 human lung specimens. The C allele of a synonymous variant, rs8040868, predicting a p.(S45=) in the gene for cholinergic receptor nicotinic alpha 3 (CHRNA3) was associated with COPD (p = 8.8 x 10(-3)). This association remained (p = 0.003 and OR = 1.4, 95 % CI 1.1-1.7) when analysing all available cases and controls in OLIN (n = 1,534). The rs8040868 variant is in linkage disequilibrium with rs16969968 previously associated with COPD and altered expression of the CHRNA5 gene. A follow-up analysis for detection of expression quantitative trait loci revealed that rs8040868-C was found to be significantly associated with a decreased expression of the nearby gene cholinergic receptor, nicotinic, alpha 5 (CHRNA5) in lung tissue. Conclusion: Our data replicate previous result suggesting CHRNA5 as a candidate gene for COPD and rs8040868 as a risk variant for the development of COPD in the Swedish population.

Background: In subjects with chronic obstructive pulmonary disease (COPD), symptoms of fatigue, concomitant heart disease and low physical activity levels are more frequently described than in subjects without COPD. However, there are no population-based studies addressing the relationship between physical activity, fatigue and heart disease in COPD. The aim was to compare physical activity levels among subjects with and without COPD in a population based study, and to evaluate if concomitant heart disease and fatigue was associated to physical activity. Methods: In this, 470 subjects with COPD and 659 subjects without COPD (non-COPD) participated in examinations including structured interview and spirometry. A ratio of the forced expiratory volume in one second (FEV1)/best of forced vital capacity (FVC) and vital capacity (VC) <0.7 was used to define COPD. Physical activity was assessed with the International Physical Activity Questionnaire (IPAQ), and fatigue with the Functional Assessment of Chronic Illness Therapy - Fatigue scale (FACIT-F). Results: The prevalence of low physical activity was higher among subjects with FEV1 <80% predicted compared to non-COPD subjects (22.4% vs. 14.6%, p = 0.041). The factors most strongly associated with low physical activity in subjects with COPD were older age, OR 1.52, (95% CI 1.12-2.06), a history of heart disease, OR 2.11 (1.10-4.08), and clinically significant fatigue, OR 2.33 (1.31-4.13); while obesity was the only significant factor among non-COPD subjects, OR 2.26 (1.17-4.35). Conclusion: Physical activity levels are reduced when lung function is decreased below 80% of predicted, and the factors associated with low physical activity are different among subject with and without COPD. We propose that the presence of fatigue and heart disease are useful to evaluate when identifying subjects for pulmonary rehabilitation.

BackgroundAnimal sensitization is a major determinant of asthma in children. Component-resolved studies of unselected pediatric populations are lacking. The aim was to describe sensitization to animal components and the association with asthma and rhinitis in animal-sensitized schoolchildren. MethodsA random sample of 696 children (11-12years) from a Swedish population-based cohort was tested for sensitization to cat, dog, and horse dander using ImmunoCAP. Sera from animal-sensitized children were further analyzed by microarray including three allergen components from cat, four from dog, and two from horse. The parents completed an expanded ISAAC questionnaire. ResultsOf 259 animal-sensitized children (0.1 kU(A)/l), 51% were sensitized to all three, 23% to two, and 25% to one species. Current asthma and asthma symptoms following contact with cats were associated with co-sensitization to Fel d 1 and Fel d 4. This association was seen already at moderate-level sensitization (1-15 ISU) to Fel d 4, at which level most children were sensitized to Fel d 1, as well. In dog-sensitized children, the majority was sensitized to more than one dog component, and co-sensitization to Can f 5 and Can f 1/f 2 conferred the greatest risk for asthma. Sensitization to the highly cross-reactive serum albumins was uncommon and not associated with asthma. ConclusionsAmong schoolchildren in northern Sweden, where mite allergy is uncommon, furry animals were the primary perennial sensitizers. Asthma was associated with higher levels of component sensitization, and sensitization to more than one component from the same animal conferred the greatest risk.