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- Wang, Gang, et al.
(författare)
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Spirometric phenotypes from early childhood to young adulthood : a Chronic Airway Disease Early Stratification study
- 2021
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Ingår i: ERJ Open Research. - : ERS Publications. - 2312-0541. ; 7:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: The prevalences of obstructive and restrictive spirometric phenotypes, and their relation to early-life risk factors from childhood to young adulthood remain poorly understood. The aim was to explore these phenotypes and associations with well-known respiratory risk factors across ages and populations in European cohorts.Methods: We studied 49334 participants from 14 population-based cohorts in different age groups (⩽10, >10–15, >15–20, >20–25 years, and overall, 5–25 years). The obstructive phenotype was defined as forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) z-score less than the lower limit of normal (LLN), whereas the restrictive phenotype was defined as FEV1/FVC z-score ⩾LLN, and FVC z-score Results: The prevalence of obstructive and restrictive phenotypes varied from 3.2–10.9% and 1.8–7.7%, respectively, without clear age trends. A diagnosis of asthma (adjusted odds ratio (aOR=2.55, 95% CI 2.14–3.04), preterm birth (aOR=1.84, 1.27–2.66), maternal smoking during pregnancy (aOR=1.16, 95% CI 1.01–1.35) and family history of asthma (aOR=1.44, 95% CI 1.25–1.66) were associated with a higher prevalence of obstructive, but not restrictive, phenotype across ages (5–25 years). A higher current body mass index (BMI was more often observed in those with the obstructive phenotype but less in those with the restrictive phenotype (aOR=1.05, 95% CI 1.03–1.06 and aOR=0.81, 95% CI 0.78–0.85, per kg·m−2 increase in BMI, respectively). Current smoking was associated with the obstructive phenotype in participants older than 10 years (aOR=1.24, 95% CI 1.05–1.46).Conclusion: Obstructive and restrictive phenotypes were found to be relatively prevalent during childhood, which supports the early origins concept. Several well-known respiratory risk factors were associated with the obstructive phenotype, whereas only low BMI was associated with the restrictive phenotype, suggesting different underlying pathobiology of these two phenotypes.
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| 2. |
- Bolger, Claire, et al.
(författare)
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Urinary cc16 levels in winter versus summer sport athletes after eucapnic voluntary hyperpnoea
- 2009
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Konferensbidrag (refereegranskat)abstract
- Exercise induced bronchoconstriction (EIB) is highly prevalent in elite athletes, especially in those training in cold dry environments. Dehydration of the airways plays a key role in this process. EIB has recently been linked to airway epithelial injury in asthmatic individuals. The aim of the study is to determine whether a short period of hyperpnoea of dry air causes airway epithelial disruption in winter and/or summer sport athletes. We hypothesise that urinary level of the Clara cell protein (CC16) – an indirect marker of permeability/cellular integrity of the lung epithelial barrier – will be increased after a eucapnic voluntary hyperpnoea (EVH) test and that this increase will be larger in winter compared to summer athletes. Forty two female athletes – 28 summer athletes (age 31.1+/-1.7yr (SEM), training volume 9+/-1.1h/wk) and 14 winter athletes (age 21.4+/-0.8yr, training volume 12.0 ± 1.10h/wk) – took part in this study. They all performed an 8-min EVH test at a target ventilation rate of 30 times their baseline forced expiratory volume in one second (FEV1). After the challenge, FEV1 was measured in duplicate at 2, 5, 10, 15, 20, 30, 60 and 90min. A sustained decrease in FEV1 of at least 10% from baseline was considered positive. Urine samples were collected at baseline and at 30, 60 and 90min recovery. CC16 concentration was measured by enzyme immunoassay. Ten summer athletes had a positive test (max FEV1 fall = 19.6+/-2.4%), whilst eighteen of the summer athletes and all the winter athletes were negative (max FEV1 fall = 5.7+/-0.7% and 5.3+/-0.7%, respectively). CC16 increased significantly after the challenge in all three groups (P<0.01) with no difference between groups: delta CC16 (max post-EVH minus baseline) in summer EVH negative athletes was 0.241+/-0.1 ng/μmol creatinine, 0.292+/-0.085 ng/μmol creatinine in summer EVH positive athletes, and 0.123+/-0.047ng/μmol creatinine in winter EVH negative athletes (P=0.415)In conclusion, a short period of hyperpnoea of dry air is associated with an increased rate of CC16 excretion in urine in both winter and summer athletes. This suggests that the integrity of the airway epithelium might be compromised by loss of airway surface lining fluid when athletes inhale dry air at high flow rates. This appears to occur irrespective of the degree of bronchoconstriction or regular training environment.
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