| 1. |
- Backman, Helena, et al.
(författare)
-
Eosinophilic inflammation and lung function decline in a long-term follow-up of a large population-based asthma cohort
- 2018
-
Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 52
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The relationship between lung function decline and airway inflammation among asthmatics has important therapeutic implications, but has rarely been studied in large samples or in population-based asthma cohorts.A population-based adult asthma cohort (n=2055) was recruited during 1986-2001 and clinically examined including spirometry. In 2012-2014, all still eligible subjects (n=1425) were invited to a clinical follow-up including spirometry, blood sampling, and a structured interview, and n=1006 participated (55% women, mean age 59y, 32-92y). Linear regression was performed with age, sex, smoking habits, year of first examination, family history of asthma, socioeconomic status, eosinophils (EOS)>=0.3x109/L, and neutrophils (NEUT)>=5.0x109/L as independent variables and pre-bronchodilator FEV1 decline/year (ml and % of predicted [pp], respectively) as dependent. In secondary models, both ICS use at baseline and ICS use at follow-up were also included.The mean annual FEV1 decline in ml (pp) among asthmatics with EOS<0.3, 0.4>EOS>=0.3 and EOS>=0.4x109/L, respectively, was 26ml (0.03pp), 29ml (0.10pp) and 34ml (0.27pp) (p<0.001). In adjusted analyses, EOS>=0.3 was significantly associated with FEV1 decline, both in terms of ml (4ml excess annual decline vs EOS<0.3) and pp. The association between EOS and FEV1 decline in pp, but not ml, remained when additionally adjusted for ICS use. The association with NEUT>=5.0x109/L was less clear.On group level, adult asthmatics with higher levels of eosinophils in blood have a history of excess FEV1 decline compared to asthmatics with lower levels of eosinophil inflammation, independent of other factors such as ICS use.
|
|
| 2. |
- Backman, Helena, et al.
(författare)
-
FEV1 decline in relation to blood eosinophils and neutrophils in a population-based asthma cohort
- 2020
-
Ingår i: World Allergy Organization Journal. - : Elsevier. - 1939-4551. ; 13:3
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The relationship between lung function decline and eosinophils and neutrophils has important therapeutic implications among asthmatics, but it has rarely been studied in large cohort studies.Objective: The aim is to study the relationship between blood eosinophils and neutrophils and FEV1 decline in a long-term follow-up of a population-based adult asthma cohort.Methods: In 2012-2014, an adult asthma cohort was invited to a follow-up including spirometry, blood sampling, and structured interviews, and n = 892 participated (55% women, mean age 59 y, 32-92 y). Blood eosinophils, neutrophils and FEV 1 decline were analyzed both as continuous variables and divided into categories with different cut-offs. Regression models adjusted for smoking, exposure to vapors, gas, dust, or fumes (VGDF), use of inhaled and oral corticosteroids, and other possible confounders were utilized to analyze the relationship between eosinophils and neutrophils at follow-up and FEV1 decline.Results: The mean follow-up time was 18 years, and the mean FEV 1 decline was 27 ml/year. The annual FEV1 decline was related to higher levels of both blood eosinophils and neutrophils at follow-up, but only the association with eosinophils remained when adjusted for confounders. Further, the association between FEV1 decline and eosinophils was stronger among those using ICS. With EOS <0.3 × 109/L as reference, a more rapid decline in FEV1 was independently related to EOS ≥0.4 × 109/L in adjusted analyses.Conclusions and clinical relevance: Besides emphasizing the importance of smoking cessation and reduction of other harmful exposures, our real-world results indicate that there is an independent relationship between blood eosinophils and FEV1 decline among adults with asthma.
|
|
| 3. |
- Backman, Helena, et al.
(författare)
-
Severe asthma : A population study perspective
- 2019
-
Ingår i: Clinical and Experimental Allergy. - : John Wiley & Sons. - 0954-7894 .- 1365-2222. ; 49:6, s. 819-828
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundSevere asthma is a considerable challenge for patients, health care professionals and society. Few studies have estimated the prevalence of severe asthma according to modern definitions of which none based on a population study.ObjectiveTo describe characteristics and estimate the prevalence of severe asthma in a large adult population‐based asthma cohort followed for 10‐28 years.MethodsN=1006 subjects with asthma participated in a follow‐up during 2012‐14, when 830 (mean age 59y, 56% women) still had current asthma. Severe asthma was defined according to three internationally well‐known criteria: the ATS workshop definition from 2000 used in the US Severe Asthma Research Program (SARP), the 2014 ATS/ERS Task force definition and the GINA 2017. All subjects with severe asthma according to any of these criteria were undergoing respiratory specialist care, and were also contacted by telephone to verify treatment adherence.ResultsThe prevalence of severe asthma according to the three definitions was 3.6% (US SARP), 4.8% (ERS/ATS Taskforce), and 6.1% (GINA) among subjects with current asthma. Although all were using high ICS doses and other maintenance treatment, >40% had uncontrolled asthma according to the asthma control test. Severe asthma was related to age >50 years, nasal polyposis, impaired lung function, sensitization to aspergillus, and tended to be more common in women. Further, neutrophils in blood significantly discriminated severe asthma from other asthma.Conclusions and clinical relevanceSevere asthma differed significantly from other asthma in terms of demographic, clinical and inflammatory characteristics, results suggesting possibilities for improved treatment regimens of severe asthma. The prevalence of severe asthma in this asthma cohort was 4‐6%, corresponding to approximately 0.5% of the general population.
|
|
| 4. |
- Backman, Helena, et al.
(författare)
-
Severe asthma among adults : Prevalence and clinical characteristics
- 2018
-
Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 52
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: Severe asthma is a considerable challenge for patients, health care professionals and society. Few studies have estimated the prevalence of severe asthma according to modern definitions of which none based on a population study.Methods: We estimated the prevalence and studied characteristics of severe asthma in a large adult population-based asthma cohort followed for 10-28 years in northern Sweden: 1006 subjects participated in a follow-up during 2012-14, when 830 (82.5%) still had current asthma (mean age 59y, 32-92y, 56% women). Severe asthma was defined according to three internationally well-known criteria: the US SARP, ATS/ERS and GINA. All subjects with severe asthma were undergoing respiratory specialist care, and were also contacted by telephone to verify adherence to treatment.Results: The prevalence of severe asthma according to the three definitions was 3.6% (US SARP), 4.8% (ERS/ATS), and 6.1% (GINA) among subjects with current asthma. Although all were using high ICS doses and other maintenance treatment, >40% had uncontrolled asthma and <10% had controlled asthma according to the ACT. Severe asthma was related to age >50 years, nasal polyposis, decreased FEV1, not fully reversible airway obstruction, sensitization to aspergillus, elevated neutrophils and partly to eosinophils, and tended to be more common in women.Conclusion: The prevalence of severe asthma in this asthma cohort was 4-6%, corresponding to approximately 0.5% of the population in northern Sweden. A substantial proportion of those with severe asthma had uncontrolled disease, and severe asthma differed significantly from other asthma in terms of both clinical and inflammatory characteristics.
|
|
