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.

Second-hand smoke exposure in adulthood and lower respiratory health during 20 year follow up in the European Community Respiratory Health Survey.

BACKGROUND: Early life exposure to tobacco smoke has been extensively studied but the role of second-hand smoke (SHS) for new-onset respiratory symptoms and lung function decline in adulthood has not been widely investigated in longitudinal studies. Our aim is to investigate the associations of exposure to SHS in adults with respiratory symptoms, respiratory conditions and lung function over 20 years. METHODS: We used information from 3011 adults from 26 centres in 12 countries who participated in the European Community Respiratory Health Surveys I-III and were never or former smokers at all three surveys. Associations of SHS exposure with respiratory health (asthma symptom score, asthma, chronic bronchitis, COPD) were analysed using generalised linear mixed-effects models adjusted for confounding factors (including sex, age, smoking status, socioeconomic status and allergic sensitisation). Linear mixed-effects models with additional adjustment for height were used to assess the relationships between SHS exposure and lung function levels and decline. RESULTS: Reported exposure to SHS decreased in all 26 study centres over time. The prevalence of SHS exposure was 38.7% at baseline (1990-1994) and 7.1% after the 20-year follow-up (2008-2011). On average 2.4% of the study participants were not exposed at the first, but were exposed at the third examination. An increase in SHS exposure over time was associated with doctor-diagnosed asthma (odds ratio (OR): 2.7; 95% confidence interval (95%-CI): 1.2-5.9), chronic bronchitis (OR: 4.8; 95%-CI: 1.6-15.0), asthma symptom score (count ratio (CR): 1.9; 95%-CI: 1.2-2.9) and dyspnoea (OR: 2.7; 95%-CI: 1.1-6.7) compared to never exposed to SHS. Associations between increase in SHS exposure and incidence of COPD (OR: 2.0; 95%-CI: 0.6-6.0) or lung function (ß: - 49 ml; 95%-CI: -132, 35 for FEV1 and ß: - 62 ml; 95%-CI: -165, 40 for FVC) were not apparent. CONCLUSION: Exposure to second-hand smoke may lead to respiratory symptoms, but this is not accompanied by lung function changes.

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.

Survival and future need of long-term oxygen therapy for chronic obstructive pulmonary disease--gender differences.

We aimed to study trends in gender-related differences in incidence, and prevalence for long-term oxygen therapy due to chronic obstructive pulmonary disease. Another aim was to study survival after onset of oxygen therapy. Prospectively followed were 5689 Swedish patients, who were prescribed oxygen therapy because of chronic obstructive pulmonary disease from 1987 to 2000. The annual incidence of women starting oxygen therapy increased more rapidly than that in men. In 2000, 7.6 per 100,000 women started treatment compared with 7.1 in men. The frequency of ever smoking in Sweden in the age group receiving oxygen, i.e. age 65-84 years, was 36.4% in women and 65.0% in men, indicating that women ran a higher risk of developing an oxygen-requiring chronic hypoxaemia. An increase in women requiring oxygen therapy is predicted due to the increase in smoking frequency in young and middle-aged women and it is estimated that about 70% of Swedish patients on oxygen in 2026 will be women, with an estimated prevalence of 61 per 100,000. In conclusion, the incidence and prevalence for long-term oxygen therapy increases more rapidly among women than in men. This is probably due to the increased frequency of smoking in women compared with men and a higher susceptibility to develop severe hypoxaemia in women. The survival is better in women with long-term oxygen therapy than in men.