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Purpose: Chronic rhinosinusitis (CRS) is related to asthma and chronic obstructive pulmonary disease (COPD). However, combined data on CRS, pulmonary function, lower airway symptoms, and cigarette smoking from the general population are lacking. The current study investigates the relationships between CRS and chronic airflow limitation (CAL), lower airway symptoms and COPD in a middle-aged population of ever-smokers and never-smokers.

Patients and Methods: All subjects from the Swedish CArdioPulmonary bioImage Study (SCAPIS) were included. Subjects underwent spirometry after bronchodilation. Chronic airflow limitation was defined as FEV1/FVC ratio <0.7. Computed tomography imaging of the thorax was performed to detect the presence of emphysema, and the subjects answered a comprehensive questionnaire on CRS, lower airway symptoms, asthma, chronic bronchitis, and cigarette smoking habits.

Results: In total, 30,154 adult subjects in the age range of 50–64 years were included. The prevalence of CRS was 5.6%. CRS was more-prevalent among subjects in the following categories: CAL (7.6%), lower airway symptoms (15.7%), current smokers (8.2%), asthma (13.6%), never-smokers and ever-smokers with COPD (17.6% and 15.3%, respectively), emphysema (6.7%), and chronic bronchitis (24.5%). In the adjusted regression model, CRS was significantly associated with CAL (OR 1.40), lower airway symptoms (OR 4.59), chronic bronchitis (OR 6.48), asthma (OR 3.08), and COPD (OR 3.10).

Conclusion: In this national, randomly chosen population sample of more than 30,000 middle-aged men and women, CRS is associated with CAL, lower airway symptoms, chronic bronchitis, asthma, and COPD. In patients with CRS and in patients with lower airway inflammation, it is important to consider the inflammatory status of the entire airway system.

Background: Chronic airway obstruction (CAO) and restrictive spirometry pattern (RSP) are associated with mortality, but sex-specific patterns of all-cause and specific causes of death have hardly been evaluated.

Objectives: To study the possible sex-dependent differences of all-cause mortality and patterns of cause-specific mortality among men and women with CAO and RSP, respectively, to that of normal lung function (NLF).

Design: Population-based prospective cohort study.

Methods: Individuals with CAO [FEV1/vital capacity (VC) < 0.70], RSP [FEV₁/VC ⩾ 0.70 and forced vital capacity (FVC) < 80% predicted] and NLF (FEV₁/VC ⩾ 0.70 and FVC ⩾ 80% predicted) were identified within the Obstructive Lung Disease in Northern Sweden (OLIN) studies in 2002–2004. Mortality data were collected through April 2016, totally covering 19,000 patient-years. Cox regression and Fine–Gray regression accounting for competing risks were utilized to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for age, body mass index, sex, smoking habits and pack-years.

Results: The adjusted hazard for all-cause mortality was higher in CAO and RSP than in NLF (HR, 95% CI; 1.69, 1.31–2.02 and 1.24, 1.06–1.71), and the higher hazards were driven by males. CAO had a higher hazard of respiratory and cardiovascular death than NLF (2.68, 1.05–6.82 and 1.40, 1.04–1.90). The hazard of respiratory death was significant in women (3.41, 1.05–11.07) while the hazard of cardiovascular death was significant in men (1.49, 1.01–2.22). In RSP, the higher hazard for respiratory death remained after adjustment (2.68, 1.05–6.82) but not for cardiovascular death (1.11, 0.74–1.66), with a similar pattern in both sexes.

Conclusion: The higher hazard for all-cause mortality in CAO and RSP than in NLF was male driven. CAO was associated with respiratory death in women and cardiovascular death in men, while RSP is associated with respiratory death, similarly in both sexes.

Background: Breathlessness is common in the population and can be related to a range of medical conditions. We aimed to evaluate the burden of breathlessness related to different medical conditions in a middle-aged population.

Methods: Cross-sectional analysis of the population-based Swedish CArdioPulmonary bioImage Study of adults aged 50–64 years. Breathlessness (modified Medical Research Council [mMRC] ≥ 2) was evaluated in relation to self-reported symptoms, stress, depression; physician-diagnosed conditions; measured body mass index (BMI), spirometry, venous haemoglobin concentration, coronary artery calcification and stenosis [computer tomography (CT) angiography], and pulmonary emphysema (high-resolution CT). For each condition, the prevalence and breathlessness population attributable fraction (PAF) were calculated, overall and by sex, smoking history, and presence/absence of self-reported cardiorespiratory disease.

Results: We included 25,948 people aged 57.5 ± [SD] 4.4; 51% women; 37% former and 12% current smokers; 43% overweight (BMI 25.0–29.9), 21% obese (BMI ≥ 30); 25% with respiratory disease, 14% depression, 9% cardiac disease, and 3% anemia. Breathlessness was present in 3.7%. Medical conditions most strongly related to the breathlessness prevalence were (PAF 95%CI): overweight and obesity (59.6–66.0%), stress (31.6–76.8%), respiratory disease (20.1–37.1%), depression (17.1–26.6%), cardiac disease (6.3–12.7%), anemia (0.8–3.3%), and peripheral arterial disease (0.3–0.8%). Stress was the main factor in women and current smokers.

Conclusion: Breathlessness mainly relates to overweight/obesity and stress and to a lesser extent to comorbidities like respiratory, depressive, and cardiac disorders among middle-aged people in a high-income setting—supporting the importance of lifestyle interventions to reduce the burden of breathlessness in the population.

Background: Exercise-induced laryngeal obstruction (EILO) is diagnosed by the continuous laryngoscopy during exercise (CLE) test. Whether or how much CLE test scores vary over time is unknown. This study aimed to compare CLE test scores in athletes over time, irrespective of respiratory symptoms and grade of laryngeal obstruction. Methods: Ninety-eight athletes previously screened for EILO were invited for a follow-up CLE test irrespective of CLE scores and respiratory symptoms. Twenty-nine athletes aged 16–27 did a follow-up CLE test 3–23 months after the baseline test. Laryngeal obstruction at the glottic and supraglottic levels was graded by the observer during exercise, at baseline and follow-up, using a visual grade score (0–3 points). Results: At baseline, 11 (38%) of the 29 athletes had moderate laryngeal obstruction and received advice on breathing technique; among them, 8 (73%) reported exercise-induced dyspnea during the last 12 months. At follow-up, 8 (73%) of the athletes receiving advice on breathing technique had an unchanged supraglottic score. Three (17%) of the 18 athletes with no or mild laryngeal obstruction at baseline had moderate supraglottic obstruction at follow-up, and none of the 3 reported exercise-induced dyspnea. Conclusions: In athletes with repeated testing, CLE scores remain mostly stable over 3–24 months even with advice on breathing technique to those with EILO. However, there is some intraindividual variability in CLE scores over time. Trial registration: ISRCTN, ISRCTN60543467, 2020/08/23, retrospectively registered, ISRCTN – ISRCTN60543467: Investigating conditions causing breathlessness in athletes.

Longitudinal studies are needed to increase our knowledge of the natural history of asthma in athletes. Our aims were to estimate the incidence, remission, and relapse, of self-reported asthma among endurance athletes. A postal questionnaire on self-reported physician-diagnosed asthma, asthma medication, allergy, and respiratory symptoms was sent annually 2011–2015 to 666 Swedish elite athletes competing in cross-country skiing, biathlon, ski orienteering, or orienteering. Athletes at risk for (1) incident asthma were those without previous self-reported asthma, use of asthma medication, or asthma-like symptoms, (2) remission those who discontinued asthma medication usage and (3) relapse those who resumed asthma medication usage during the observation period. The population at risk was used as denominator in the calculations of subsequent event rate. At baseline, 89% responded, the median age was 17 years and 47% were females. Of the 373 athletes with never asthma nor use of asthma medication/asthma-like symptoms at baseline, 31 (8%) reported physician-diagnosed asthma during follow-up, giving an adjusted incidence rate of asthma of 42/1000 person years. Among the 110 athletes with self-reported asthma and use of asthma medication at baseline, 26 (24%) discontinued use of asthma medication during the follow-up, giving a remission rate of 142/1000 person years. Of the 31 athletes with previous asthma and no use of asthma medication at baseline, 9 (29%) resumed use of asthma medication during follow-up, giving a relapse rate was 148/1000 person years. Elite endurance athletes have a high incidence of self-reported physician-diagnosed asthma. The remission and relapse of self-reported asthma medication usage in endurance athletes appear similar to that of the general population.

Background and Aims: Winter endurance athletes have a high prevalence of exercise-induced bronchoconstriction (EIB) and asthma, probably due to repeated and prolonged inhalation of cold and dry air. Heat- and moisture-exchanging devices (HME) warm and humidify inhaled air and prevent EIB. The aim of this study was to share cross-country skiers and biathletes' experiences of training and competition in low temperatures, views on temperature limits, usage of HME, and consequences of cold exposure on their health.

Methods: Eleven Swedish World Championship or Olympic medalists in cross-country skiing and biathlon were interviewed and transcripts were analyzed using qualitative content analysis. Results: Participants described how cold temperatures predominantly affected the airways, face, and extremities. During training, extreme cold was managed by choosing warmer clothing, modification of planned sessions, use of HME, delaying training, or changing location. In competition, participants described limited possibility for such choices and would prefer adjustment of existing rules (i.e., more conservative temperature limits), especially since they understood elite skiing in low temperatures to present an occupational hazard to their health. Participants had at times used HMEs during training in cold environments but described mixed motives for their use—that HMEs warm and humidify cold inhaled air but introduce additional resistance to breathing and can cause problems due to mucus and ice build-up. Skiers also perceived that they had become more sensitive to cold during the latter part of their careers.

Conclusions: The present study gives a unique insight into the “cold” reality of being an elite athlete in skiing and biathlon. Cold exposure results in negative health consequences that are preventable, which means that rules must be followed, and organizers should acknowledge responsibility in protecting athletes from occupational hazards. Development of evidence-based guidelines for protection of athletes' respiratory health should be a focus for future translational research.

Background: Interstitial lung abnormalities (ILA) are incidental findings on chest computed tomography (CT). These patterns can present at an early stage of fibrotic lung disease. Our aim was to estimate the prevalence of ILA in the Swedish population, in particular in never-smokers, and find out its association with demographics, comorbidities and symptoms.

Methods: Participants were recruited to the Swedish CArdioPulmonary BioImage Study (SCAPIS), a population-based survey including men and women aged 50–64 years performed at six university hospitals in Sweden. CT scan, spirometry and questionnaires were performed. ILA were defined as cysts, ground-glass opacities, reticular abnormality, bronchiectasis and honeycombing.

Findings: Out of 29 521 participants, 14 487 were never-smokers and 14 380 were men. In the whole population, 2870 (9.7%) had ILA of which 134 (0.5%) were fibrotic. In never-smokers, the prevalence was 7.9% of which 0.3% were fibrotic. In the whole population, age, smoking history, chronic bronchitis, cancer, coronary artery calcium score and high-sensitive C-reactive protein were associated with ILA. Both ILA and fibrotic ILA were associated with restrictive spirometric pattern and impaired diffusing capacity of the lung for carbon monoxide. However, individuals with ILA did not report more symptoms compared with individuals without ILA.

Interpretation: ILA are common in a middle-aged Swedish population including never-smokers. ILA may be at risk of being underdiagnosed among never-smokers since they are not a target for screening.

Background: Adult-onset asthma is associated with a poor treatment response. The aim was to study associations between clinical characteristics, asthma control and treatment in adult-onset asthma.

Methods: Previous participants within the population-based Obstructive Lung Disease in Northern Sweden studies (OLIN) were in 2019–2020 invited to clinical examinations including structured interviews, spirometry, fractional exhaled nitric oxide (FeNO), skin prick test and blood sampling. In total, n = 251 individuals with adult-onset asthma (debut >15 years of age) were identified. Uncontrolled asthma was defined according to ERS/ATS and treatment step according to GINA (2019).

Results: Among individuals with uncontrolled asthma (34%), severe obesity (16.3% vs 7.9%, p = 0.041) and elevated levels of blood neutrophils, both regarding mean level of blood neutrophils (4.25*109/L vs 3.67*109/L, p = 0.003), and proportions with ≥4*109/L (49.4% vs 33.3%, p = 0.017) and ≥5*109/L (32.1% vs 13.7%, p < 0.001) were more common than among those with controlled asthma. Adding the dimension of GINA treatment step 1–5, individuals with uncontrolled asthma on step 4–5 treatment had the highest proportions of blood neutrophils ≥5*109/L (45.5%), severe obesity (BMI≥35, 26.1%), dyspnea (mMRC≥2) (34.8%), and most impaired lung function in terms of FEV1%<80% of predicted (42.9%), FEV1<LLN (47.6%), FVC<80% of predicted (42.9%) and FVC < LLN (38.1%). No associations between level of asthma control and treatment were found regarding blood eosinophils, FeNO or allergic sensitization.

Conclusion: This study indicates that in adult-onset asthma, primarily non-type-2 characteristics such as obesity and blood neutrophils associate with poor asthma control and higher doses of inhaled corticosteroids.

Purpose: Cold air exposure is associated with increased respiratory morbidity and mortality. Repeated inhalation of cold and dry air is considered the cause of the high prevalence of asthma among winter endurance athletes. This study assessed whether a heat- and moisture-exchanging breathing device (HME) attenuates airway responses to high-intensity exercise in sub-zero temperatures among healthy subjects.

Methods: Using a randomized cross-over design, 23 healthy trained participants performed a 30-min warm-up followed by a 4-min maximal, self-paced running time trial in − 15 °C, with and without HME. Lung function was assessed pre- and immediately post-trials. Club cell protein (CC-16), 8-isoprostane, and cytokine concentrations were measured in plasma and urine pre- and 60 min post trials. Symptoms were assessed prior to, during, and immediately after each trial in the chamber.

Results: HME use attenuated the decrease in forced expiratory volume in 1 s (FEV1) post trials (∆FEV1: mean (SD) HME − 0.5 (1.9) % vs. no-HME − 2.7 (2.7) %, p = 0.002). HME also substantially attenuated the median relative increase in plasma-CC16 concentrations (with HME + 27% (interquartile range 9–38) vs no-HME + 121% (55–162), p < 0.001) and reduced airway and general symptom intensity, compared to the trial without HME. No significant changes between trials were detected in urine CC16, 8-isoprostane, or cytokine concentrations.

Conclusion: The HME attenuated acute airway responses induced by moderate-to-maximal-intensity exercise in − 15 °C in healthy subjects. Further studies are needed to examine whether this HMEs could constitute primary prevention against asthma in winter endurance athletes.

The purpose of this study was to investigate the resistance to breathing (RES) in heat and moisture exchanging devices (HME) intended for use during physical activity in the cold. RES was investigated for seventeen HMEs, including different types of filters. In addition, the influence of headwind on RES was tested using four representative HMEs. HMEs were mounted to the face of an artificial head manufactured from ABS plastic. The HMEs were connected to a mechanical lung simulator, which delivered standardised inspiratory and expiratory air flow rates (V⋅, L/s). The delta pressure (Δp, Pa) between ambient air and the air inside the HME was measured, whereupon RES was calculated. The results showed significant (p < 0.05) differences in RES between HMEs from different manufacturers, while the difference was smaller, and in some cases not significant (p > 0.05), between different models/filters within the same brand. The results also showed that RES was highly influenced by different ventilations and headwind conditions. RES increased with increased V⋅ and, when a headwind was introduced, RES decreased during inspiration and increased during expiration. Calculations showed that the oxygen and energy cost for breathing through an HME was very small for most of the tested models. The effect of HME dead space on pulmonary gas fractions depends on the tidal volume. At large tidal volumes and ventilations, the effect of HMEs on pulmonary gas fractions becomes relatively small.