Plasma proteins elevated in severe asthma despite oral steroid use and unrelated to Type-2 inflammation.

RATIONALE: Asthma phenotyping requires novel biomarker discovery. OBJECTIVES: To identify plasma biomarkers associated with asthma phenotypes by application of a new proteomic panel to samples from two well-characterised cohorts of severe (SA) and mild-to-moderate (MMA) asthmatics, COPD subjects and healthy controls (HCs). METHODS: An antibody-based array targeting 177 proteins predominantly involved in pathways relevant to inflammation, lipid metabolism, signal transduction and extracellular matrix was applied to plasma from 525 asthmatics and HCs in the U-BIOPRED cohort, and 142 subjects with asthma and COPD from the validation cohort BIOAIR. Effects of oral corticosteroids (OCS) were determined by a 2-week, placebo-controlled OCS trial in BIOAIR, and confirmed by relation to objective OCS measures in U-BIOPRED. RESULTS: In U-BIOPRED, 110 proteins were significantly different, mostly elevated, in SA compared to MMA and HCs. 10 proteins were elevated in SA versus MMA in both U-BIOPRED and BIOAIR (alpha-1-antichymotrypsin, apolipoprotein-E, complement component 9, complement factor I, macrophage inflammatory protein-3, interleukin-6, sphingomyelin phosphodiesterase 3, TNF receptor superfamily member 11a, transforming growth factor-ß and glutathione S-transferase). OCS treatment decreased most proteins, yet differences between SA and MMA remained following correction for OCS use. Consensus clustering of U-BIOPRED protein data yielded six clusters associated with asthma control, quality of life, blood neutrophils, high-sensitivity C-reactive protein and body mass index, but not Type-2 inflammatory biomarkers. The mast cell specific enzyme carboxypeptidase A3 was one major contributor to cluster differentiation. CONCLUSIONS: The plasma proteomic panel revealed previously unexplored yet potentially useful Type-2-independent biomarkers and validated several proteins with established involvement in the pathophysiology of SA.

The burden of food allergy on children and teens: A systematic review.

BACKGROUND: Over the last two decades, researchers have placed increasing attention on understanding how food allergy affects the health-related quality of life (HRQL) and psychosocial well-being of children and teens. In response, a number of reviews have been published that aim at synthesizing the literature. However, many of these papers focus narrowly on HRQL or suffer from methodological limitations. METHOD: The current review aims to fill this gap by providing a comprehensive overview of the burden of pediatric food allergy by synthesizing the quantitative and qualitative literature. RESULTS: Findings from the present review provide evidence of reduced HRQL among children and teens with food allergy, particularly older children and those with more severe manifestations of the condition. In comparison to HRQL, the link between food allergy and psychosocial functioning is less clear; however, some evidence can be cited linking food allergy to greater levels of psychological distress. Qualitative evidence suggests that the burden of pediatric food allergy largely stems from worries surrounding exposures outside of the home and the social consequences of the condition. The current review also highlights several gaps in the literature, including a paucity of longitudinal research, research focused on predictors of psychological distress among children and teens with food allergy as well as a dearth of studies comparing rates of bullying in food-allergic and non-food-allergic samples. CONCLUSION: More emphasis should be placed on not only alleviating the social and psychological consequences of food allergy, but also on identifying and assisting those most acutely burdened by the condition.

Lung function fluctuation patterns unveil asthma and COPD phenotypes unrelated to type 2 inflammation.

BACKGROUND: In all chronic airway diseases, the dynamics of airway function are influenced by underlying airway inflammation and bronchial hyperresponsiveness along with limitations in reversibility owing to airway and lung remodeling as well as mucous plugging. The relative contribution of each component translates into specific clinical patterns of symptoms, quality of life, exacerbation risk, and treatment success. OBJECTIVE: We aimed to evaluate whether subgrouping of patients with obstructive airway diseases according to patterns of fluctuation in lung function allows identification of specific phenotypes with distinct clinical characteristics. METHODS: We applied the novel method of fluctuation-based clustering (FBC) to twice-daily FEV1 measurements recorded over a 1-year period in a mixed group of 134 adults with mild-to-moderate asthma, severe asthma, or chronic obstructive pulmonary disease from the European BIOAIR cohort. RESULTS: Independently of clinical diagnosis, FBC divided patients into 4 fluctuation-based clusters with progressively increasing alterations in lung function that corresponded to patterns of increasing clinical severity, risk of exacerbation, and lower quality of life. Clusters of patients with airway disease with significantly elevated levels of biomarkers relating to remodeling (osteonectin) and cellular senescence (plasminogen activator inhibitor-1), accompanied by a loss of airway reversibility, pulmonary hyperinflation, and loss of diffusion capacity, were identified. The 4 clusters generated were stable over time and revealed no differences in levels of markers of type 2 inflammation (blood eosinophils and periostin). CONCLUSION: FBC-based phenotyping provides another level of information that is complementary to clinical diagnosis and unrelated to eosinophilic inflammation, which could identify patients who may benefit from specific treatment strategies or closer monitoring.

Multimorbidity in asthma, association with allergy, inflammatory markers and symptom burden, results from the Swedish GA2 LEN study.

BACKGROUND: Asthma is common worldwide and a large part of subjects with asthma have concomitant allergic multimorbidity in the form of rhinitis and/or eczema. OBJECTIVE: The aim of this study is to investigate whether the presence of allergic multimorbidity in asthma relates to allergic sensitization, allergic and respiratory symptoms, quality of life, inflammatory markers, lung function, use of medication and background factors. METHODS: A total of 437 asthmatics from the (GA2 LEN) cross-sectional survey in Sweden were grouped depending on the presence of rhinitis and/or eczema. The impact of allergic multimorbidity was assessed in terms of allergic sensitization, allergic and respiratory symptoms, quality of life, type-2 inflammatory markers (exhaled nitric oxide, eosinophil activation markers, periostin), lung function, use of medication and background factors. RESULTS: Subjects with asthma, rhinitis and eczema were more likely to be sensitized to seasonal allergens (67% vs 32%, P < .001), food allergens (54% vs 18%, P < .001) and to have a higher degree of sensitization than subjects with only asthma (23% vs 10%, P < .001). Subjects with allergic multimorbidity more often had allergic reactions to food (28% vs 10%, P = .002), more respiratory symptoms and anxiety/depression (40% vs, 14%, P < .001) than subjects with only asthma, despite having similar levels of type 2 inflammatory markers. Individuals with allergic multimorbidity were more likely to be diagnosed with asthma before the age of 12 (48% vs 27%, P = .016) and to have maternal heredity for allergy (53% vs 33%, P = .011) than subjects with only asthma. CONCLUSION AND CLINICAL RELEVANCE: Asthmatics with allergic multimorbidity are more likely to be sensitized to seasonal aeroallergens, food allergens and they have a higher degree of sensitization compared with those with only asthma. Allergic multimorbidity is associated with respiratory and allergy symptoms, anxiety and/or depression.

A scoping review of the caregiver burden of pediatric food allergy.

OBJECTIVE: Although a number of articles have described the psychosocial impact of raising a child with a food allergy, recent attempts at synthesizing this literature have been narrow in focus or methodologically limited. Consequently, this study aimed to synthesize both the quantitative and qualitative literature to achieve a better understanding of the psychosocial and financial burdens faced by families who raise children with food allergy. DATA SOURCES: Searches were performed on PubMed, Scopus, PsycInfo, and Cumulative Index to Nursing and Allied Health Literature databases for articles related to the psychosocial and financial burden experienced by individuals who care for a child with food allergy. STUDY SELECTIONS: English language, original research articles were included in this review. RESULTS: A total of 54 articles were deemed eligible for review. Results from the quantitative literature revealed that parents of children with food allergy (ie, food allergy and food protein-induced enterocolitis, proctocolitis, and enteropathy) consistently reported lower quality of life than their comparison groups. Within-group analyses suggest that this burden is increased for parents who manage multiple food allergies, severe food allergy, and comorbid allergic conditions. Thematic synthesis of the qualitative literature suggests that the psychosocial burden shouldered by parents of children with food allergy stems, in part, from the unpredictable threat of exposure and the practical and social burdens of managing a food allergy. In addition to psychosocial burdens, a small but growing body of literature suggests that families with food allergy also incur greater financial costs. CONCLUSION: Findings suggest that pediatric food allergy imposes considerable burdens on parents both quantitatively and qualitatively.

Upper airway and skin symptoms in allergic and non-allergic asthma: Results from the Swedish GA2LEN study.

BACKGROUND: Allergic and non-allergic asthma are viewed as separate entities, despite sharing similarities. The aims of this study were to determine differences in symptoms from the upper airways and the skin in allergic and non-allergic asthma. The secondary aims were to identify childhood risk factors and to compare quality of life in the two asthma groups. METHODS: This cohort (age 17-76 years) consisted of 575 subjects with allergic or non-allergic asthma and 219 controls. The participants participated in an interview, spirometry, FeNO, skin prick test, and responded to the Mini Asthma Quality of Life Questionnaire. RESULTS: Self-reported allergic rhinitis was significantly more common in both allergic and non-allergic asthma (82.3 and 40.7%) groups compared with the controls. The prevalence of chronic rhinosinusitis (CRS) was similar in both asthma groups. Eczema was significantly more common in both asthmatic groups (72.3 and 59.8%) than controls (47.0%) (p < 0.001 and p = 0.012). Severe respiratory infection in childhood and parental allergy were risk factors for both allergic and non-allergic asthma groups. Quality of life was significantly lower in non-allergic than allergic asthma groups (p = 0.01). CONCLUSION: Concomitant symptoms from the upper airways and the skin were significantly more common in both allergic and non-allergic asthma. This indicates that non-allergic asthma has a systemic component with similarities to what is found in allergic asthma. There were similarities in the childhood risk factor pattern between the two types of asthma but asthma-related quality of life was lower in the non-allergic asthma group.

Excessive daytime sleepiness in asthma: What are the risk factors?

OBJECTIVE: Previous studies have found that excessive daytime sleepiness (EDS) is a more common problem in asthmatic subjects than in the general population. The aim of this study was to investigate whether the prevalence of EDS is increased in asthmatic subjects and, if so, to analyse the occurrence of potential risk factors for EDS in asthmatics. METHODS: Cross-sectional epidemiological study. In 2008, a postal questionnaire was sent out to a random sample of 45,000 individuals aged 16-75 years in four Swedish cities. RESULTS: Of the 25,160 persons who participated, 7.3% were defined as having asthma. The prevalence of EDS was significantly higher in asthmatic subjects (42.1% vs. 28.5%, p < 0.001) compared with non-asthmatic subjects. Asthma was an independent risk factor for EDS (adjusted OR 1.29) and the risk of having EDS increased with asthma severity. Risk factors for EDS in subjects with asthma included insomnia (OR, 3.87; 95% CI, 3.10-4.84); chronic rhinosinusitis (OR, 2.00; 95% CI, 1.53-2.62); current smoking (OR, 1.60; 95% CI, 1.15-2.22) and obesity (OR, 1.53; 95% CI, 1.09-2.13). CONCLUSIONS: EDS is a common problem among subjects with asthma. Asthma is an independent risk factor for having EDS. Furthermore, subjects with asthma often have other risk factors for EDS, many of them potentially modifiable.

Clinical and inflammatory characteristics of the European U-BIOPRED adult severe asthma cohort.

U-BIOPRED is a European Union consortium of 20 academic institutions, 11 pharmaceutical companies and six patient organisations with the objective of improving the understanding of asthma disease mechanisms using a systems biology approach.This cross-sectional assessment of adults with severe asthma, mild/moderate asthma and healthy controls from 11 European countries consisted of analyses of patient-reported outcomes, lung function, blood and airway inflammatory measurements.Patients with severe asthma (nonsmokers, n=311; smokers/ex-smokers, n=110) had more symptoms and exacerbations compared to patients with mild/moderate disease (n=88) (2.5 exacerbations versus 0.4 in the preceding 12 months; p<0.001), with worse quality of life, and higher levels of anxiety and depression. They also had a higher incidence of nasal polyps and gastro-oesophageal reflux with lower lung function. Sputum eosinophil count was higher in severe asthma compared to mild/moderate asthma (median count 2.99% versus 1.05%; p=0.004) despite treatment with higher doses of inhaled and/or oral corticosteroids.Consistent with other severe asthma cohorts, U-BIOPRED is characterised by poor symptom control, increased comorbidity and airway inflammation, despite high levels of treatment. It is well suited to identify asthma phenotypes using the array of "omic" datasets that are at the core of this systems medicine approach.

Detection of exacerbations in asthma based on electronic diary data: results from the 1-year prospective BIOAIR study.

BACKGROUND: Objective measures are required that may be used as a proxy for exacerbations in asthma. The aim was to determine the sensitivity and specificity of electronic diary data to detect severe exacerbations (SEs) of asthma. A secondary aim was to identify phenotypic variables associated with a higher risk of exacerbation. METHODS: In the BIOAIR study, 169 patients with asthma (93 severe (SA); 76 mild to moderate (MA)) recorded lung function, symptoms and medication use in electronic diaries for 1 year. Data were analysed using receiver-operator characteristics curves and related to physician-diagnosed exacerbations. Medical history and baseline clinical data were used to assess risk of exacerbation. RESULTS: Of 122 physician-diagnosed exacerbations, 104 occurred in the SA group (1.1 per patient/year), 18 in the MA group (0.2 per patient/year) and 63 were severe using American Thoracic Society/European Respiratory Society criteria. During exacerbations, peak expiratory flow (PEF) and forced expiratory volume in 1 s significantly decreased, whereas day and night symptoms significantly increased. An algorithm combining a 20% decrease in PEF or a 20% increase in day symptoms on 2 consecutive days was able to detect SEs with 65% sensitivity and 95% specificity. The strongest risk factors for SEs were low Asthma Control Questionnaire score, sputum eosinophils ≥ 3%, body mass index >25 and low quality of life (St George's Respiratory Questionnaire), with ORs between 3.61 and 2.22 (p<0.05). CONCLUSIONS: Regular electronic monitoring of PEF and asthma symptoms provides an acceptable sensitivity and specificity for the detection of SEs and may be suitable for personal internet-based monitoring of asthma control.

The negative health effects of having a combination of snoring and insomnia.

STUDY OBJECTIVES: Insomnia and snoring are common sleep disorders. The aim was to investigate the association of having a combination of insomnia symptoms and snoring with comorbidity and daytime sleepiness. METHODS: The study population comprised 25,901 participants (16-75 years, 54.4% women) from 4 Swedish cities, who answered a postal questionnaire that contained questions on snoring, insomnia symptoms (difficulties initiating and/or maintaining sleep and/or early morning awakening), smoking, educational level, and respiratory and nonrespiratory disorders. RESULTS: Snoring was reported by 4,221 (16.2%), while 9,872 (38.1%) reported ≥ 1 insomnia symptom. A total of 2,150 (8.3%) participants reported both insomnia symptoms and snoring. The association with hypertension (adjusted odds ratio [OR], 1.4; 95% confidence interval [CI], 1.2-1.6), chronic obstructive pulmonary disease (adjusted OR, 1.8; 95% CI, 1.3-2.4), asthma (adjusted OR, 1.9; 95% CI, 1.6-2.3), daytime sleepiness (adjusted OR, 7.9; 95% CI, 7.1-8.8), and the use of hypnotics (adjusted OR, 7.5; 95% CI, 6.1-9.1) was highest for the group with both insomnia symptoms and snoring. CONCLUSIONS: Participants with both snoring and insomnia run an increased risk of hypertension, chronic obstructive pulmonary disease, asthma, daytime sleepiness, and use of hypnotics. It is important to consider snoring in patients seeking medical assistance for insomnia and, vice versa, in patients with snoring inquiring about insomnia. CITATION: Hägg SA, Ilieva E, Ljunggren M, et al. The negative health effects of having a combination of snoring and insomnia. J Clin Sleep Med. 2022;18(4):973-981.

Risk Factors for the Absence of Diagnosis of Asthma Despite Disease Symptoms: Results from the Swedish GA2LEN Study.

BACKGROUND: Asthma is a common chronic disease presenting with airway symptoms such as wheezing, chest tightness and attacks of breathlessness. Underdiagnosis of asthma is common and correlates to negative outcomes such as a lower quality of life and reduced work capacity. PURPOSE: This study aims to identify factors for not being diagnosed with asthma if presenting with asthma symptoms. PATIENTS AND METHODS: A questionnaire was sent to 45,000 subjects (age 16-74 years) in Sweden. Subjects who reported both wheeze and breathlessness and wheeze when not having a cold were defined as having asthma-related symptoms. Data on demographics, educational level, smoking, physical activity, comorbidities, symptoms and asthma were collected. Logistic regression was used to identify risk factors for not being diagnosed with asthma. RESULTS: Of the 25,391 who responded to the survey, 6.2% reported asthma-related symptoms. Of these, 946 had been diagnosed with asthma previously, while 632 had not. Independent risk factors for not being diagnosed with asthma were higher age (OR (95% CI) (2.17 (1.39-3.40))), male sex (1.46 (1.17-1.81)), current smoking (2.92 (2.22-3.84)), low level of education (1.43 (1.01-2.01)), low physical activity (1.36 (1.06-1.74)), and hypertension (1.50 (1.06-2.12)). CONCLUSION: Men, smokers, older subjects, and those with low educational level or low physical activity are less likely to be diagnosed with asthma despite presenting asthma-related symptoms.

Snoring and environmental exposure: results from the Swedish GA2LEN study.

OBJECTIVE: Habitual snoring is associated with fatigue, headaches and low work performance. This cross-sectional study aimed to investigate if snoring is affected by environmental factors such as home dampness and exposure to air pollution. SETTING: General population sample from four Swedish cities. PARTICIPANTS: 25 848 participants from the Swedish part of the epidemiological Global Asthma and Allergy and European network of excellence study carried out in 2008. The participants completed a postal questionnaire on snoring and, indoor and outdoor environmental exposure as well as potential confounders including smoking, weight, height and educational level. RESULTS: Of the participants, 4211 (16.3%) were habitual snorers. Habitual snorers reported water damage (8.3% vs 7.0% p<0.0001), floor dampness (4.6% vs 3.8% % p<0.0001) and visible mould (5.2% vs 3.8% p<0.0001) in their homes more often than non-snorers. Habitual snorers stated being annoyed by air pollution more often than non-snorers with habitual snorers reporting being irritated with the air in their residential area to a higher extent (sometimes 16.2% vs 13.9%, and daily 4.6% vs 3.1%) as well as annoyance from traffic fumes (somewhat 19% vs 18.5% and very 5% vs 3.6%) (p<0.0001). These results remained significant after adjustment for age, body mass index, smoking history and educational level. CONCLUSION: Snoring is more prevalent in subjects reporting home dampness and air pollution. These association should be confirmed in further research using objective measurements and a longitudinal approach.

Food allergy-related concerns during the transition to self-management.

BACKGROUND: Compared to non-allergic individuals, food allergic individuals have impaired health-related quality of life (HRQL). However, effects of gender and age are unclear. The objective of our study was to describe associations between allergies to common foods and HRQL with consideration to gender and age. METHODS: Adolescents and adults (N = 137; 49.6% males) with specialist-diagnosed allergy to milk, egg and/or wheat completed age-appropriate versions of the Food Allergy Quality of Life Questionnaire (FAQLQ). We pooled common questions and calculated overall- and domain-specific HRQL in association with number and severity of symptoms and time elapse since worst reaction. RESULTS: In the entire study population, HRQL was not affected by gender or age, whereas gender-specific age categories affected HRQL among males only. For example, males 18-39 years had worse overall- (ß = 0.77; 95% CI 0.08-1.45) and domain-specific HRQL vs. males < 18 years. Among participants with 1-3 food allergy symptoms, no associations were found. Among participants with 4-6 symptoms, the domain allergen avoidance and dietary restrictions was worse among older participants (e.g. 40+ years: ß = 0.71; 95% CI 0.05-1.37 vs. < 18 years), and males 18-39 vs. < 18 years. Among participants with severe symptoms, females vs. males, and participants 18-39 vs. < 18 years had worse HRQL. At least 4 years since worst reaction was associated with worse HRQL for participants 40+ years vs. < 18 years, and older males vs. males < 18 years. Nearly all differences exceeded the clinical relevance threshold of ≥ 0.5. CONCLUSIONS: Associations between allergies to common foods and HRQL are affected by gender and age. Most affected are males 18-39 years. Among females, HRQL is more stable across age groups.

Health-related quality of life worsens by school age amongst children with food allergy.

BACKGROUND: Food allergy is negatively associated with health-related quality of life (HRQL). Although differences exist between parents and children, less is known about age-specific differences amongst children. As such, we aimed to identify if age, as well as other factors, are associated with food allergy-specific HRQL in an objectively defined population of children. METHODS: Overall, 63 children (boys: n = 36; 57.1%) with specialist-diagnosed food allergy to 1 + foods were included. Parents/guardians completed the Swedish version of a disease-specific questionnaire designed to assess overall- and domain-specific HRQL. Descriptive statistics and linear regression were used. RESULTS: The most common food allergy was hen's egg (n = 40/63; 63.5%). Most children had more than one food allergy (n = 48; 76.2%). Nearly all had experienced mild symptoms (e.g. skin; n = 56/63; 94.9%), and more than half had severe symptoms (e.g. respiratory; 39/63; 66.1%). Compared to young children (0-5 years), older children (6-12 years) had worse HRQL (e.g. overall HRQL: B = 0.60; 95% CI 0.05-1.16; p < 0.04.). Similarly, multiple food allergies, and severe symptoms were significantly associated with worse HRQL (all p < 0.05) even in models adjusted for concomitant allergic disease. No associations were found for gender or socioeconomic status. CONCLUSION: Older children and those with severe food allergy have worse HRQL.

Pediatric food allergy-related household costs are influenced by age, but not disease severity.

OBJECTIVE: The economic burden of food allergy on households is poorly understood. We evaluated the household costs associated with specialist-diagnosed pediatric food allergy, with focus on age and disease severity. STUDY DESIGN: A cross-sectional study of 70 Swedish case-control pairs (59% boys) was conducted using Food Allergy Economic questionnaire. Household costs were analyzed between age- and gender-matched cases (children aged 0-17 years, with specialist-diagnosed food allergy) and controls (non-food allergic households). RESULTS: Parents were predominantly university-educated and employed full-time. Most cases had parent-reported previous anaphylaxis. Mean total annual household costs were comparable between cases and controls. However, compared to controls, cases had significantly higher direct medical-, and non-medical related costs; higher indirect medical-related costs, and higher intangible costs (all p < 0.05). In a sensitivity analyses of only cases aged 0-12 years, direct household costs, including lost earnings due to child's hospitalization, were significantly higher than controls. Results from only children with severe disease paralleled those of all cases vs. controls. CONCLUSIONS: Although pediatric food allergy is not associated with higher total annual household costs, these households have significantly higher direct medical-related, indirect and intangible costs vs. non-food allergic households. Higher household costs were identified amongst younger children, but not disease severity.

Asthma and COPD overlap (ACO) is related to a high burden of sleep disturbance and respiratory symptoms: Results from the RHINE and Swedish GA2LEN surveys.

BACKGROUND: The term Asthma and COPD Overlap (ACO) describes a condition where asthma and COPD overlap. We aimed to investigate associations between ACO and insomnia and respiratory symptoms, and to investigate the prevalence of ACO and the characteristics of subjects with ACO in two Northern European population studies. METHODS: The study comprised 25 429 subjects aged ≥ 40 years who participated in one of two Northern European general population surveys. Both surveys included questions on asthma, COPD, respiratory and sleep-related symptoms, including difficulty initiating sleep, difficulty maintaining sleep, early-morning awakening, and excessive daytime sleepiness. ACO was defined as having both self-reported asthma and COPD. RESULTS: The prevalence of ACO was 1.0%. The group with ACO had a higher prevalence of both insomnia and respiratory symptoms than subjects with only asthma or COPD. Having ACO was independently associated with a 2-3 times higher probability of having sleep-related symptoms as compared with the group without asthma or COPD, after adjustment for age, sex, BMI, smoking history and educational level (adjusted odds ratio 2.14-3.36, 95% CI). CONCLUSION: Subjects with ACO have a high prevalence of insomnia and respiratory symptoms. To our knowledge, this is the first study to assess the association between sleep-related symptoms and ACO.

An investigation on the use of snus and its association with respiratory and sleep-related symptoms: a cross-sectional population study.

INTRODUCTION: Studies of the health effects of moist oral tobacco, snus, have produced inconsistent results. The main objective of this study is to examine the health effects of snus use on asthma, respiratory symptoms and sleep-related problems, a field that has not been investigated before. METHODS AND MATERIAL: This cross-sectional study was based on a postal questionnaire completed by 26 697 (59.3%) participants aged 16 to 75 years and living in Sweden. The questionnaire included questions on tobacco use, asthma, respiratory symptoms and sleeping problems. The association of snus use with asthma, respiratory symptoms and sleep-related symptoms was mainly tested in never-smokers (n=16 082). RESULTS: The current use of snus in never-smokers was associated with an increased risk of asthma (OR 1.51 (95% CI 1.28 to 1.77)), asthmatic symptoms, chronic bronchitis and chronic rhinosinusitis. This association was not present among ex-snus users. Snoring was independently related to both the former and current use of snus ((OR 1.37 (95% CI 1.12 to 1.68)) and (OR 1.59 (95% CI 1.34 to 1.89), respectively)). A higher risk of difficulty inducing sleep was seen among snus users. CONCLUSION: Snus use was associated with a higher prevalence of asthma, respiratory symptoms and snoring. Healthcare professionals should be aware of these possible adverse effects of snus use.