Vibeke Backer

Bispebjerg Hospital, Copenhagen University, København, Capital Region, Denmark

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Publications (247)808.36 Total impact

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    ABSTRACT: The aim of the present study was to examine the effect of beta2-adrenergic stimulation on skeletal muscle contractile properties, sarcoplasmic reticulum (SR) rates of Ca2+ release and uptake, and Na+/K+-ATPase-activity before and after fatiguing exercise in trained men. The study consisted of two experiments (EXP1, n = 10 M, EXP2, n = 20 M), where beta2-adrenoceptor agonist (terbutaline) or placebo was randomly administered in double-blinded crossover designs. In EXP1, maximal voluntary isometric contraction of m.quadriceps (MVC) was measured, followed by exercise to fatigue at 120% of Vo2max. A muscle biopsy was taken after MVC (non-fatigue) and at time of fatigue. In EXP2, contractile properties of m.quadriceps were measured with electrical stimulations before (non-fatigue) and after two fatiguing 45-s sprints. Non-fatigued MVC was 6±3 and 6±2% higher (P < 0.05) for terbutaline than placebo in EXP1 and EXP2. Furthermore, peak twitch force was 11±7% higher (P < 0.01) for terbutaline than placebo at non-fatigue. After sprints, MVC declined (P < 0.05) to same levels for terbutaline as placebo, whereas peak twitch force was lower (P < 0.05) and half relaxation time prolonged (P < 0.05) with terbutaline. Rates of SR Ca2+ release and uptake at 400 nM [Ca2+] were 15±5 and 14±5% (P < 0.05) higher for terbutaline than placebo at non-fatigue, but declined (P < 0.05) to similar levels at time of fatigue. Na+/K+-ATPase-activity was unaffected by terbutaline compared with placebo at non-fatigue, but terbutaline counteracted exercise-induced reductions in Vmax at time of fatigue. In conclusion, increased contractile force induced by beta2-adrenergic stimulation is associated with enhanced rate of Ca2+ release in humans. While beta2-adrenergic stimulation elicits positive inotropic and lusitropic effects of non-fatigued m.quadriceps, these effects are blunted when muscles fatigue.This article is protected by copyright. All rights reserved
    The Journal of Physiology 10/2014; · 4.38 Impact Factor
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    ABSTRACT: Background Eosinophil cationic protein (ECP) is one of four basic proteins of the secretory granules of eosinophils. It has a variety of functions associated with inflammatory responses. Little is known about the causes for variation in serum ECP levels.AimTo identify factors associated with variation in serum ECP and to determine the relative proportion of the variation in ECP due to genetic and non-genetic factors, in an adult twin sample.MethodsA sample of 575 twins, selected through a proband with self-reported asthma, had serum ECP, lung function, airway responsiveness to methacholine, exhaled nitric oxide, and skin test reactivity, measured. Linear regression analysis and variance component models were used to study factors associated with variation in ECP and the relative genetic influence on ECP levels.ResultsSex (regression coefficient =-0.107, p<0.001), BMI (0.007, p=0.028) and airway responsiveness to methacholine (0.074, p=0.001) were significantly associated with ECP. Adjusted for these factors, ECP correlated 0.53 (p<0.001) and 0.27 (p=0.001) in monozygotic and dizygotic twins, respectively (p-value for difference=0.05). According to the most parsimonious variance component model, genetic factors accounted for 57% (CI: 42-72%, p<0.001) of the variance in ECP levels, whereas the remainder (43%) was ascribable to non-shared environmental factors. The genetic correlation between ECP and airway responsiveness to methacholine was statistically non-significant (r=-0.11, p=0.50).Conclusion Around half of all variance in serum ECP is explained by genetic factors. Serum ECP is influenced by sex, BMI and airway responsiveness. Serum ECP and airway responsiveness seem not to share genetic variance.This article is protected by copyright. All rights reserved.
    Clinical & Experimental Allergy 10/2014; · 4.79 Impact Factor
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    ABSTRACT: Background: Chronic rhinosinusitis (CRS) is a common health problem that is subclassified as CRS with nasal polyps (CRSwNPs) or CRS without NPs (CRSsNP). In accordance with the united airways concept, CRSwNPs frequently coexists with asthma but to date, this association remains unexplained and its strength is uncertain. Here, we aimed to examine the association between CRSwNPs and asthma in collaboration between the neighboring specialities: otorhinolaryngology and respiratory medicine. Methods: A prospective clinical study was performed comprising 40 CRS patients scheduled for functional endoscopic sinus surgery and 21 control persons. We performed nasal endoscopy, peak expiratory flow, spirometry, and bronchodilation tests. In selected cases, additional pulmonary tests were performed. Atopy was assessed by skin-prick test or by measuring specific IgE in serum. Results: Asthma was diagnosed in 26 patients with CRSwNPs (65%; odds ratio = 5.9 [1.79, 19.65]; p = 0.003), and 5 control persons (24%). Twenty-five percent of the CRSwNP patients had undiagnosed asthma. Atopy was not significantly associated with CRSwNPs (p = 0.39) or with coexisting asthma within the CRSwNP group (p = 0.50). Conclusion: Compared with previous studies, we found a very high prevalence of asthma and, frequently, asthma was undiagnosed. Furthermore, CRSwNPs was associated with chronic bronchitis and, in those with asthma, lower airway obstruction. These results call for a closer collaboration between otorhinolaryngology and respiratory medicine in relation to patients with CRSwNPs, in research as well as in clinical practice.
    American journal of rhinology & allergy 10/2014; 28(5). · 1.74 Impact Factor
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    ABSTRACT: In a randomized double-blind crossover design, we investigated the effect of the beta2-agonist terbutaline on endurance performance and substrate utilization in nine moderately trained males (maximum oxygen uptake (VO2max): 58.9±3.1 mL min(-1) kg(-1)). Subjects performed 60 min of submaximal exercise (65-70% of VO2max) immediately followed by a 300-kcal time trial with inhalation of either terbutaline (TER) or placebo (PLA). Pulmonary gas exchange was measured during the submaximal exercise and muscle biopsies were collected before and after the exercise bouts. Time trial performance was not different between PLA and TER (1054±125 vs. 1072±145 s). During the submaximal exercise, respiratory exchange ratio, glycogen breakdown (PLA: 195±28; TER: 266±32 mmol kg dw(-1)) and muscle lactate accumulation (PLA: 13.2±1.2; TER: 20.3±1.6 mmol kg dw(-1)) were higher (P<0.05) with TER than PLA. There was no difference between PLA and TER in net muscle glycogen utilization and lactate accumulation during the time trial. IMTG did not change with treatment or exercise. PDH-E1α Ser(293) and Ser(300) phosphorylation were lower (P<0.05) before the submaximal exercise with TER than PLA with no difference after the submaximal exercise and the time trial. Before the submaximal exercise, ACC2 Ser(221) phosphorylation was higher (P<0.05) with TER than PLA. There was no difference in αAMPK Thr(172) phosphorylation between treatments. The present study suggests that beta2-agonists do not enhance 300-kcal time trial performance, but increase carbohydrate metabolism in skeletal muscles during submaximal exercise independent of AMPK and ACC phosphorylation, and that this effect diminishes as drug exposure time, exercise duration and intensity are increased.
    Journal of applied physiology (Bethesda, Md. : 1985). 09/2014;
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    ABSTRACT: Abstract Objective: Using endometrial secretion analysis, we assessed whether altered inflammatory cytokine levels can be detected in the uterine environment in asthma patients, thereby providing a possible cause of reduced fertility in asthmatics. Methods: Forty-four unexplained infertile women (aged 28-44) underwent asthma and allergy testing, questionnaires, endometrial secretion and blood samples in the mid-secretory phase of the menstrual cycle (day 19-23) during assisted reproduction. Differences in cytokines and growth factors were analyzed. Results: Mean log-VEGF in uteri was lower in asthma patients compared with controls (2.29 vs. 2.70, p=0.028). This was mainly due to lower values of VEGF among women with non-atopic asthma compared with women with atopic asthma (1.86 vs. 2.72, p=0.009) and with healthy controls (1.86 vs. 2.70, p=0.01). Asthma treatment status had no effect on VEGF levels in uteri. Serum high sensitivity CRP was negatively correlated with VEGF in endometrial secretions. No other significant correlations were observed between peripheral blood values and markers found in utero. Conclusion: Asthma is associated with lower values of VEGF in uterine endometrial secretions, which might affect the receptiveness of the endometrium and thereby increase time to pregnancy. The effect appears to be associated with non-atopic asthma with general increased systemic inflammation.
    The Journal of asthma : official journal of the Association for the Care of Asthma. 09/2014;
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    ABSTRACT: Elite athletes frequently suffer from asthma and airway hyperresponsiveness (AHR). We aimed to investigate predictors of airway pathophysiology in a group of unselected elite summer-sport athletes, training for the summer 2008 Olympic Games, including markers of airway inflammation, systemic inflammation and training intensity.
    Medicine and science in sports and exercise. 09/2014;
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    ABSTRACT: Background Smoking is a major risk factor for lung diseases and lower respiratory symptoms, but since not all smokers develop chronic bronchitis and since chronic bronchitis is also diagnosed in never-smokers, it has been suggested that some individuals are more susceptible to develop chronic bronchitis due to genetics. Objective To study the relative influence of genetic and environmental factors on the variation in the susceptibility to chronic bronchitis. Methods In a population-based questionnaire study of 13,649 twins, 50-71 years of age, from the Danish Twin Registry, we calculated sex-specific concordance rates and heritability of chronic bronchitis. The response rate was 75%. Results The prevalence of chronic bronchitis was 9.3% among men and 8.5% among women. The concordance rate for chronic bronchitis was higher in monozygotic twins than in dizygotic twins among women; 0.30 vs. 0.17, but not among men; 0.15 vs. 0.18. The heritability of chronic bronchitis adjusted for smoking and age was 55% (36-71%) in women, whereas the susceptibility to chronic bronchitis in men for 25% (8-41%) was ascribable to familial environment but not to genetic factors. Conclusions Chronic bronchitis shows a moderate familial aggregation, particularly in women. Increased susceptibility to respiratory disease among female smokers relative to male smokers may have a genetic origin.
    Respiratory Medicine 09/2014; · 2.59 Impact Factor
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    ABSTRACT: Upper respiratory tract infections with common virusses is the most frequent cause of asthma exacerbations. Numerous defects in both epithelial function, pathogen recognition and innate immune signalling has been demonstrated in patients with asthma. The subject of this review is these recent findings and the potential therapeutic targets that are being identified.
    Ugeskrift for laeger 09/2014; 176(36).
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    ABSTRACT: Exercise-induced bronchoconstriction (EIB) describes the phenomenon of transient airway narrowing in association with physical activity. Although it may seem likely that EIB would have a detrimental impact on athletic performance, this has yet to be established.
    Sports medicine (Auckland, N.Z.). 08/2014;
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    ABSTRACT: The purpose of the present study was to investigate the effect of high-dose inhaled terbutaline on muscle strength, maximal sprinting, and time-trial performance in trained men.
    European journal of applied physiology. 08/2014;
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    ABSTRACT: Our objective was to investigate effects of acute and 2-week administration of oral salbutamol on repeated sprint ability, exercise performance, and muscle strength in elite endurance athletes. Twenty male elite athletes [VO2max: 69.4 ± 1.8 (Mean ± SE) mL/min/kg], aged 25.9 ± 1.4 years, were included in a randomized, double-blinded and placebo-controlled parallel study. At baseline, after acute administration, and again after 2-week administration of the study drugs (8 mg salbutamol or placebo), subjects' maximal voluntary contraction (MVC) of m. quadriceps and isometric endurance of m. deltoideus were measured, followed by three repeated Wingate tests. Exercise performance at 110% of VO2max was determined on a bike ergometer. Acute administration of salbutamol increased peak power during first Wingate test by 4.1 ± 1.7% (P < 0.05). Two-week administration of salbutamol increased (P < 0.05) peak power during first and second Wingate test by 6.4 ± 2.0 and 4.2 ± 1.0%. Neither acute nor 2-week administration of salbutamol had any effect on MVC, exercise performance at 110% of VO2max or on isometric endurance. No differences were observed in the placebo group. In conclusion, salbutamol benefits athletes' sprint ability. Thus, the present study supports the restriction of oral salbutamol in competitive sports.
    Scandinavian Journal of Medicine and Science in Sports 08/2014; · 3.21 Impact Factor
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    ABSTRACT: Background The prevalence of severe asthma is unknown. However, international expert statements estimate that severe asthma represents 5% to 10 % of the entire asthma population. Objective Based on register data from a nationwide population, we wanted to investigate the prevalence of severe asthma, the extent of asthma control, and contact with specialist care. Methods A descriptive cross-sectional register study was performed. By using a nationwide prescription database, we identified current patients with asthma (age, 18-44 years) in 2010. Severity was classified as severe versus mild-moderate asthma according to the level of antiasthma treatment. We investigated prescription drug use, hospitalizations, emergency department visits, and outpatient clinic visits according to severity. Results Among a nationwide population, we identified 61,583 current patients with asthma. Based on the level of antiasthma treatment, 8.1% of identified patients was classified as having severe asthma. Low asthma control (dispensed prescriptions of prednisolone, emergency department visits, hospitalization, or excessive short-acting β2-agonist use) was more frequent in subjects with severe asthma (36.4% vs 25.2%, P < .0001); 63.8% with severe asthma and low asthma control were not managed by specialist care. Patients with severe asthma with specialist contact more frequently had impaired asthma control compared with subjects not treated by a specialist (44.4% vs 33.1%, P < .0001). Conclusion Based on the level of treatment, 8.1% of a nationwide population of current patients with asthma was classified as having severe asthma. Low asthma control was more frequent among subjects with severe asthma, and only a minority had access to specialist care. There is room for optimizing asthma management, particularly among patients with severe disease.
    The Journal of Allergy and Clinical Immunology: In Practice. 07/2014;
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    ABSTRACT: Background Long-term longitudinal studies of lung function from childhood to adulthood are important in linking our understanding of childhood risk factors to adult disease. Airway hyperresponsiveness has been shown to independently affect lung function growth in studies of adolescence. The objective of the study was to test the hypothesis that airway hyperresponsiveness has an independent deleterious effect on lung function in adolescence that extends into adulthood. Methods A random population sample (n=983) aged 7-17 from Copenhagen was followed longitudinally for 20 years with four examinations. Results A total of 780 (79.3%) subjects contributed with lung function measurements and bronchial provocation testing. Among these, 170 (21.8%) had airway hyperresponsiveness at one examination or more during the study period. There was no difference in initial FEV1 levels between subjects with and without airway hyperresponsiveness. In a repeated measures regression model with adjustment for asthma and smoking, airway hyperresponsiveness was independently associated with reduced rates of growth in lung function in both sexes of 23 ml/year. Reduced growth rates resulted in deficits in maximal attained level of lung function at age 18, which persisted throughout the follow-up until the last examination at age 27-37 years. Conclusion Airway hyperresponsiveness has an independent deleterious effect on lung function development from 7 to 37 years resulting in a lower maximal attained lung function and persistent deficits in lung function in adulthood.
    Respiratory medicine 05/2014; · 2.33 Impact Factor
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    ABSTRACT: trefoil factor peptides (TFF) are secreted onto mucosal surfaces together with mucins and occur in high concentrations in pulmonary secretions from patients with chronic obstructive pulmonary disease (COPD). In the present study, we aimed to explore the concentrations of the peptides in serum and sputum in patients with COPD. thirty-five individuals were included in the study, including 11 healthy individuals, 13 with asthma and 11 with COPD. TFF1, TFF2 and TFF3 were measured by ELISA in sputum induced by hypertonic saline inhalation and in serum. Total protein content in sputum was also determined. in the sputum samples from COPD patients, we observed an eight-fold higher concentration of TFF1 and a five-fold higher concentration of TFF3 compared to controls. In the serum samples from COPD patients, we observed three-, three- and two-fold higher concentrations of TFF1, TFF2 and TFF3, respectively, compared to controls. there is increased secretion of TFF peptides in the lungs of patients with COPD, as well as significant increases in serum levels. This suggests a role for TFF peptides in the pathogenesis of pulmonary diseases with mucus hypersecretion.
    The Clinical Respiratory Journal 04/2014; · 1.66 Impact Factor
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    ABSTRACT: Patterns of health-care use and comorbidities present in patients in the period before diagnosis of chronic obstructive pulmonary disease (COPD) are unknown. We investigated these factors to inform future case-finding strategies. We did a retrospective analysis of a clinical cohort in the UK with data from Jan 1, 1990 to Dec 31, 2009 (General Practice Research Database and Optimum Patient Care Research Database). We assessed patients aged 40 years or older who had an electronically coded diagnosis of COPD in their primary care records and had a minimum of 3 years of continuous practice data for COPD (2 years before diagnosis up to a maximum of 20 years, and 1 year after diagnosis) and at least two prescriptions for COPD since diagnosis. We identified missed opportunites to diagnose COPD from routinely collected patient data by reviewing patterns of health-care use and comorbidities present before diagnosis. We assessed patterns of health-care use in terms of lower respiratory consultations (infective and non-infective), lower respiratory consultations with a course of antibiotics or oral steroids, and chest radiography. If these events did not lead to a diagnosis of COPD, they were deemed to be missed opportunities. This study is registered with ClinicalTrials.gov, number NCT01655667. We assessed data for 38 859 patients. Opportunities for diagnosis were missed in 32 900 (85%) of 38 859 patients in the 5 years immediately preceding diagnosis of COPD; in 12 856 (58%) of 22 286 in the 6-10 years before diagnosis, in 3943 (42%) of 9351 in the 11-15 years before diagnosis; and in 95 (8%) of 1167 in the 16-20 years before diagnosis. Between 1990 and 2009, we noted decreases in the age at diagnosis (0·05 years of age per year, 95% CI 0·03-0·07) and yearly frequency of lower respiratory prescribing consultations (rate ratio 0·982 opportunities per year, 95% CI 0·979-0·985). Prevalence of all comorbidities present at COPD diagnosis increased except for asthma and bronchiectasis, which decreased between 1990 and 2007, from 281 (33·4%) of 842 patients to 451 of 1465 (30·8%) for asthma, and from 53 of 842 (6·3%) to 53 of 1465 (3·6%) for bronchiectasis. In the 2 years before diagnosis, of 6897 patients who had had a chest radiography, only 2296 (33%) also had spirometry. Opportunities to diagnose COPD at an earlier stage are being missed, and could be improved by case-finding in patients with lower respiratory tract symptoms and concordant long-term comorbidities. UK Department of Health, Research in Real Life.
    The lancet. Respiratory medicine. 04/2014; 2(4):267-76.
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    ABSTRACT: Abstract Background: Several studies have suggested a relationship between the age at menarche and risk of asthma. Objective: To conduct a systematic review and meta-analysis of the relationship between the age at menarche and the risk of asthma. Methods: This systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). A pre specified literature search strategy was used to identify studies of potential relevance and independent reviews were carried out by two authors. Raw data was pooled using the software package RevMan to calculate summary odds ratios. The risk of publication bias was assessed graphically by using a funnel plot and the robustness of the overall estimate obtained was assessed by using sensitivity analyses. Results: The searches identified 61 potentially relevant articles of which seven matched the inclusion criteria required for the meta-analysis, with a total of 22,859 subjects. Pooling of the seven studies showed that girls with early menarche (<12 years) had an increased risk of asthma relative to girls with late menarche; random effects odds ratio=1.37 (1.15-1.64), (p=0.0005). Substantial heterogeneity was revealed (I(2)=55%). Sensitivity analysis showed that the risk estimate was not markedly changed when excluding any of the studies. The funnel plot did not indicate publication bias. Conclusions: Early menarche appears to be associated with increased risk of asthma. Hormonal, immunological, genetic, and environmental factors may act in a developmental context to explain this relationship. Future studies are warranted to further determine the mechanisms responsible for this observation.
    Journal of Asthma 03/2014; · 1.85 Impact Factor
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    Kristian Aasbjerg, Vibeke Backer
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    ABSTRACT: Treatment for seasonal allergic rhinitis induced by airborne allergens can be divided into two major groups: symptom-dampening drugs, such as antihistamines and corticosteroids, and disease-modifying drugs in the form of immunotherapy. It has been speculated that depot-injection corticosteroids given once or twice a year are a safe and patient-friendly alternative to the time-consuming immunotherapy. Our data indicate otherwise.
    Expert Review of Clinical Immunology 02/2014; 10(2):171-3. · 2.89 Impact Factor
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    ABSTRACT: Abstract Objective: Ongoing airway inflammation measured by fractional exhaled nitric oxide (FENO) and airway hyperresponsiveness (AHR) to mannitol are associated in selected asthma patients, but no evidence exists of this association in unselected asthma patients. The aim was to investigate the association between FENO and AHR to mannitol in unselected individuals with possible asthma. Methods: A real-life study on patients with possible asthma referred to a specialized asthma clinic. Data on asthma history, FEV1, FENO, atopy, smoking, treatment and AHR to mannitol were collected. Results: In 217 unselected patients with symptoms suggestive of asthma, FENO and response to mannitol were tested. Of the 141 who underwent both tests, 32 (23%) had FENO > 25 ppb, and 58 (41%) had AHR to mannitol. A significant association between high FENO and AHR was found (p < 0.001); 26% responded to mannitol despite a normal NO, and 8% had a high FENO but no AHR. Additionally, a weak association was found between log FENO and log response to mannitol (r = 0.32, p < 0.01). The area under the ROC curve for FENO as a predictor of AHR was 0.66 (95% CI 0.6-0.8) and for mannitol for having high FENO was 0.73 (95%CI 0.6-0.9). Conclusion: In a large sample of patients referred to an asthma clinic, an association was found between FENO and AHR to mannitol. However, a significant proportion of asthma patients had a normal FENO despite having AHR, suggesting that in some patients, AHR to mannitol is not driven by eosinophilic airway inflammation.
    Journal of Asthma 01/2014; · 1.85 Impact Factor
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    ABSTRACT: The development of atopic diseases early in life suggests an important role of perinatal risk factors. To study whether early life exposures modify the genetic influence on atopic diseases in a twin population. Questionnaire data on atopic diseases from 850 monozygotic and 2,279 like-sex dizygotic twin pairs, 3-9 years of age, from the Danish Twin Registry were cross-linked with data on prematurity, Caesarean section, maternal age at birth, parental cohabitation, season of birth, and maternal smoking during pregnancy, from the Danish National Birth Registry. Significant predictors of atopic diseases were identified with logistic regression and subsequently tested for genetic effect modification using variance components analysis. After multivariable adjustment, prematurity (gestational age below 32 weeks) (OR=1.93, CI=1.45-2.56); Caesarean section (OR=1.25, CI=1.05-1.49); and maternal smoking during pregnancy (OR=1.70, CI=1.42-2.04) significantly influenced the risk of asthma, whereas none of the factors were significantly associated with atopic dermatitis and hay fever. Variance components analysis stratified by exposure status showed no significant change in the heritability of asthma according to the identified risk factors. In this population-based study of children there was no evidence of genetic effect modification of atopic diseases by several identified early life risk factors. The causal relationship between these risk factors and atopic diseases may therefore be mediated via mechanisms different from gene-environment interaction.
    The Clinical Respiratory Journal 01/2014; · 1.66 Impact Factor
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    ABSTRACT: Severe asthma is defined by persistent symptoms and frequent exacerbations despite intensive asthma therapy. The prevalence is estimated to be 5-10% of all asthmatics. Severe asthma is responsible for a major burden of illness including low quality of life and a disproportionate use of health-care resources. The clinical assessment of severe asthma must include verification of the correct diagnosis, adherence to medication, excluding differential diagnosis and identification and treatment of aggravating co-morbidities and trigger factors.
    Ugeskrift for laeger 01/2014; 176(3A).

Publication Stats

3k Citations
808.36 Total Impact Points

Institutions

  • 1995–2014
    • Bispebjerg Hospital, Copenhagen University
      • • Department of Clinical Physiology and Nuclear Medicine
      • • Department of Pulmonary Medicine
      København, Capital Region, Denmark
  • 2012
    • Uppsala University
      • Department of Medical Sciences
      Uppsala, Uppsala, Sweden
  • 2011
    • IT University of Copenhagen
      København, Capital Region, Denmark
    • Roskilde Hospital
      Roskilde, Zealand, Denmark
  • 2009
    • Imperial College London
      • Section of Airway Disease
      Londinium, England, United Kingdom
    • Statens Serum Institut
      • Department of Epidemiology Research
      Copenhagen, Capital Region, Denmark
  • 1990–2007
    • Copenhagen University Hospital Hvidovre
      • • Department of Clinical Biochemistry
      • • Department of Infectious Diseases
      Hvidovre, Capital Region, Denmark
  • 2004
    • University of Copenhagen
      København, Capital Region, Denmark
  • 2003
    • National Institute of Public Health
      København, Capital Region, Denmark
    • National Institute of Public Health, Denmark
      København, Capital Region, Denmark
  • 1999
    • Heart Research Centre
      Melbourne, Victoria, Australia
  • 1992–1996
    • Rigshospitalet
      • Department of Clinical Physiology, Nuclear Medicine and PET
      Copenhagen, Capital Region, Denmark
  • 1994
    • Glostrup Hospital
      • Department of Paediatrics
      København, Capital Region, Denmark
  • 1989–1994
    • The Ohio State University
      • • Division of Hospital Medicine
      • • Department of Internal Medicine
      Columbus, OH, United States
  • 1990–1993
    • Copenhagen University Hospital
      København, Capital Region, Denmark