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K H Carlsen

Publications and source records attributed to K H Carlsen.

At least 19 recordsLinked to original sources

European birth cohort studies on asthma and atopic diseases: I. Comparison of study designs -- a GALEN initiative.

BACKGROUND: The reasons for the rise in asthma and allergies remain unclear. To identify risk or protective factors, it is essential to carry out longitudinal epidemiological studies, preferably birth cohort studies. In Europe, several birth cohort studies on asthma and atopic diseases have been initiated over the last two decades. AIM: One of the work packages within the Global Allergy and Asthma European Network (GA(2)LEN) project was designed to identify and compare European birth cohorts on asthma and atopic diseases. The present review (part I) describes their objectives, study settings, recruitment process and follow-up rates. A subsequent review (part II) will compare outcome and exposure parameters. METHODS: For each birth cohort, we collected detailed information regarding recruitment process, study setting, baseline data (pregnancy, birth, parents/siblings) as well as follow-up rates, outcome and exposure parameters at each time point. RESULTS: We identified and assessed 18 European birth cohorts on asthma, allergic rhinitis and eczema. Six of these studies also focused on food allergies. The birth cohorts were mostly initiated in the 1990s with predominantly urban/metropolitan settings. Many studies were able to maintain high follow-up rates, even after five or more years. CONCLUSIONS: Due to the unique cooperation within the GA(2)LEN project a common database was established containing study characteristics of European birth cohorts on asthma and atopic diseases. This can be used as a basis for evaluating the possibility to pool data and perform meta-analyses, as well as to recommend criteria for conducting future birth cohorts.

Adolescent↗

European birth cohort studies on asthma and atopic diseases: II. Comparison of outcomes and exposures--a GA2LEN initiative.

BACKGROUND: The Global Allergy and Asthma European Network (GA2LEN) is a consortium of 26 leading European research centres committed to establish a European research area of excellence in the field of allergy and asthma. AIM: One of the GA2LEN work packages was designed to identify and compare the existing European birth cohort studies on asthma and atopic diseases. The present review compares their subjective and objective outcomes as well as exposure variables. METHODS: A common database was established to assess study characteristics of observational birth cohort studies designed to examine asthma and atopic diseases. Data were collected by visiting most of the participating research teams and interviewing all relevant study personnel. For each study, the type of objective/subjective outcome parameters and potentially influential factors were recorded precisely for every time point during follow-up. RESULTS: Eighteen birth cohort studies on asthma and atopic diseases were identified in eight European countries. Thirteen studies collected data on specific immunoglobulin E (IgE) to various inhalant and food allergens, whereas 12 performed skin prick tests (many at several time points during follow up). Several studies measured lung function, but across the cohorts no comparable standard procedures were used. For subjective evaluation of asthma and allergic rhinitis most studies applied the ISAAC questionnaire (sometimes modified), whereas the assessment of eczema was rather heterogeneous across the studies. CONCLUSION: This GA2LEN initiative established a unique common database of 18 European birth cohorts on asthma and atopic diseases. For selected cohorts, it seems that pooling data and performing common analyses may be possible to examine associations between certain exposure variables (e.g. pet ownership, tobacco smoke exposure and day-care) and selected outcome measures for atopy, asthma or allergic rhinitis (e.g. sensitization assessed by IgE or skin prick tests, doctor's diagnosis of asthma, parental perception regarding asthma/wheezing or hay fever symptoms).

Asthma↗

Effect of climatic change in children with atopic eczema.

BACKGROUND: Climate and sunlight (ultraviolet radiation) influence activity of atopic eczema. OBJECTIVE: To evaluate the effect of moving from a subarctic/temperate climate to a sunny subtropical climate on children's atopic eczema. METHODS: Children, 4-13 years, with severe atopic eczema were randomized to stay 4 weeks in Gran Canary (index patients = 30) and home in Norway (controls = 26), with a follow up of 3 months. SCORing of Atopic Dermatitis (SCORAD) was primary variable, and secondary were Children's Dermatology Life Quality Index (CDLQI), Staphylococcus aureus skin colonization and pharmacological skin treatment. RESULTS: SCORing of Atopic Dermatitis decreased from 37.2 (29.4-44.9) to 12.2 (9.0-15.4) [mean (95% confidence intervals)] after 4 weeks and 21.2 (17.2-25.1) 3 months thereafter in index patients (P < 0.0005), much less in controls.Children's Dermatology Life Quality Index in the index group improved from 8.7 to 2.2 and 4.5 after 4 weeks and 3 months (P < 0.0005), not in controls. Bacterial skin colonization with S. aureus decreased in the index group from 23/30 (77%) to 12/30 (40%; P = 0.001) and 12/30 (40%; P = 0.005) after 1 month and 3 months, and the use of local steroids decreased in index patients but not in controls. CONCLUSIONS: The change from a subartic/temperate to a subtropical climate for 4 weeks improved significantly skin symptoms (SCORAD) and quality of life, even for 3 months after return.

Adolescent↗

Soluble CD14 at 2 yr of age: gender-related effects of tobacco smoke exposure, recurrent infections and atopic diseases.

The endotoxin receptor soluble CD14 (sCD14) has been implicated in the 'hygiene hypothesis' suggesting reduced allergic sensitization with bacterial stimulation. However, the relationship between early life sCD14 and allergic diseases is conflicting. We aimed to investigate whether possible risk factors for allergic diseases were associated with sCD14 levels at 2 yr of age. In the nested case-control study of the birth cohort studies 'Environment and Childhood Asthma study in Oslo' 411 children selected with recurrent bronchial obstruction (rBO) (n=241) and no bronchial obstruction (n=170) by 2 yr were investigated with skin prick test and structured parental interview at age 2 yr. Exposure to tobacco smoke, pets and infections was recorded semi-annually by questionnaires (0-2 yr). The sCD14 was analysed from frozen, stored serum by ELISA technique. Regression analyses were performed in all subjects with complete data (n=406, 180 girls), and in girls and in boys separately. Mean sCD14 (ng/ml) was significantly higher among girls 2035 (1973-2096) vs. 1947 (1890-2004) (boys). The sCD14 was significantly reduced among girls exposed to antenatal maternal smoking and with parental asthma, after adjusting for age, parental rhino-conjunctivitis, pet keeping and childhood infections. Recurrent otitis media (OM) increased and common colds significantly decreased sCD14 levels in girls. Boys with atopic dermatitis and rBO had reduced sCD14. Pet exposure was not significantly associated with sCD14. We report novel gender-related effects of sCD14 in early life and suggest that gender, tobacco smoke exposure, age and middle ear disease in particular should be accounted for when assessing the role of sCD14 in childhood allergic diseases.

Age Factors↗

Effect of inhaled steroids on lung function in young children: a cohort study.

The objectives of the present study were to determine the use of inhaled corticosteroids (ICS) for treating recurrent bronchial obstruction (rBO) in young children up to 2 yrs of age and to assess possible modifying effects of ICS on lung function in young children with rBO. From an observational, noninterventional birth cohort of 3,754 newborn children (3,697 with complete questionnaire data by 2 yrs of age), 306 children with documented rBO by age 2 yrs (cases) were identified along with 306 matched controls. Two tidal flow/volume measurements were taken, one at presentation of disease (children were steroid naive) and one at 2 yrs of age (mean age 11.2 and 25.6 months, respectively), from: 21 cases who subsequently received ICS (ICS+); 33 who did not (ICS-); and in 15 controls. The mean +/- SD duration of ICS treatment was 10.3 +/- 6.5 months. The main outcomes were treatment with ICS and baseline ratio of time to peak expiratory flow/total expiratory time (tPTEF/tE). From the entire cohort, 77 children (2.1%) and 21% of children with rBO had received ICS by 2 yrs of age. Baseline tPTEF/tE was significantly lower at the first visit only in ICS+ as compared to ICS- subjects, as well as in ICS+ and ICS- as compared to controls. The mean difference in baseline tPTEF/tE from first to second visit was borderline statistically significant in the ICS+ group only and correlated significantly with duration of ICS treatment. The present observational cohort study demonstrated that one-fifth of young children with recurrent bronchial obstruction had received inhaled corticosteroids. Early inhaled corticosteroid treatment improved lung function by age 2 yrs, mostly in those with the longest duration of treatment.

Administration, Inhalation↗

Pulmonary outcome in adolescents of extreme preterm birth: a regional cohort study.

AIMS: The pulmonary outcome of extreme prematurity remains to be established in adults. We determined respiratory health and lung function status in a population-based, complete cohort of young preterms approaching adulthood. METHODS: Forty-six preterms with gestational age < or = 28 wk or birthweight < or = 1000 g, born between 1982 and 1985, were compared to the temporally nearest term-born subject of equal gender. Spirometry, plethysmography, reversibility test to salbutamol and methacholine bronchial provocation test were performed. Neonatal data were obtained from hospital records and current symptoms from validated questionnaires. RESULTS: When entering the study at a mean age of 17.7 (SD: 1.2) y, a doctor's diagnosis of asthma and use of asthma inhalers were significantly more prevalent among preterms than controls (one asthmatic control compared to nine preterms, all but one using asthma inhalers). Peak expiratory flow (PEF) and forced expiratory volume in 1 s (FEV1) were decreased and the discrepancies relative to controls increased parallel to increased severity of neonatal lung disease. Parameters of increased neonatal oxygen exposure significantly predicted FEV1. Adjusted for height, gender and age, FEV1 was reduced by a mean of 580 ml/s in subjects with a history of bronchopulmonary dysplasia. Fifty-six percent of preterms had a positive methacholine provocation test compared to 26% of controls. CONCLUSION: A substantially decreased FEV1, increased bronchial hyperresponsiveness and a number of established risk factors for steeper age-related decline in lung function were observed in preterms. A potential for early onset chronic obstructive pulmonary disease is present in subsets of this group.

Adolescent↗

Cockroach sensitivity in Norway: a previously unidentified problem?

BACKGROUND: Little is known about cockroach sensitization in Scandinavia, whereas cockroaches are implicated in allergic diseases throughout large parts of the world. In association with the Genetics of Asthma International Network (GAIN) study, we report sensitization to cockroaches and possible association with IgE-mediated diseases in Norway. METHODS: 100 Norwegian families (426 subjects) of 7-35-year-old sibling-pairs with asthma and their parents underwent questionnaire/interview (medical and exposure history), skin prick test (SPT) to common local inhalant allergens and German cockroach, and IgE specific to mites, mosquito, shrimp and cockroach. Cockroach sensitization was defined as positive if there was a positive (> or = 3 mm) skin prick test and/or presence of IgE antibody of class 2 or more. RESULTS: Thirty-one subjects (7.5%) were sensitized (five monosensitized) to cockroach (27 by skin prick test and seven by IgE antibody, all with additional inhalant allergy). Co-sensitization was most common to grass (in 61%), cat (48%), dog (48%) and mites (42%). Reported allergic diseases in cockroach-sensitized subjects were asthma and rhinitis (n = 10), asthma only (n = 9), rhinitis only (n = 2) and neither asthma nor rhinitis (n = 10). CONCLUSIONS: Since cockroach sensitization was relatively frequent in Norwegian atopic families, albeit with unclear clinical implications, we suggest that cockroach allergy should be considered in atopic subjects with respiratory disease.

Adolescent↗

[Asthma--a condition of our time, a condition in change?].

BACKGROUND: This article reviews causative factors for asthma and allergy during childhood and describes current trends in prevalence and hospitalisation for childhood asthma. MATERIALS AND METHODS: A review of the prevalence of childhood asthma in Norway over the last 50 years together with recent trends in hospitalisation for childhood asthma, is given. Possible causative factors for childhood asthma are reviewed, and recent theories for the current increase in prevalence are discussed. RESULTS AND INTERPRETATION: During the last 50 years, a steady increase in the prevalence of childhood asthma has been documented through published studies from 1948 and onwards. From 1980 and until 1990, an increase in hospital admissions due to acute asthma was observed; later, admissions have leveled off, particularly as regards readmissions. Smoking during pregnancy and childhood decreases lung function. Allergic sensitisation is related to asthma development and may occur already during pregnancy. Increased allergic sensitisation may occur due to reduced load of infections. However, respiratory virus infections, and especially RS virus and rhinovirus infections, are closely related to asthma development and symptoms during childhood. A reduction in readmissions for asthma may be related to increased use of antiinflammatory therapy for asthma.

Acute Disease↗

Eosinophil cationic protein (ECP) in school children living in a mountainous area of Norway: a population-based study of ECP as a tool for diagnosing asthma in children with reference values.

BACKGROUND: Most previous studies on eosinophil cationic protein (ECP) have been performed on carefully selected groups of asthmatic patients. Few studies based upon population cohorts have been reported. The primary objective of the present study was to assess the usefulness of serum eosinophil cationic protein (s-ECP) in the diagnosis of asthma in schoolchildren and determine reference values based on measurements in healthy children. METHODS: The population consisted of 216 schoolchildren (aged 7-16 years) who in a previous questionnaire had reported asthma or asthma-like symptoms and a control group. The questionnaire study comprised the entire population of schoolchildren in Upper Hallingdal. After clinical assessment, blood samples, and skin prick tests, these subjects were then reclassified into four groups: atopic and nonatopic asthmatic and nonasthmatics. S-ECP was assessed in relation to atopy, asthma severity, allergen exposure, and sex. RESULTS: The asthma group (n = 105) had significantly higher mean s-ECP level than the nonasthma group (n = 111) (13.3 vs 8.3 microg/l, P < 0.001), with no significant difference between atopic asthmatics and atopic nonasthmatics. Mean s-ECP levels in children with mild, moderate, or severe asthma were 12.1, 18.5, and 12.2 microg/l, respectively. The children with animal dander allergy demonstrated higher levels of s-ECP than children without this allergy (12.9 vs 9.1 microg/l, P = 0.001). The upper reference limit (determined as the 95th percentile in healthy children) of 19.1 microg/l, showed low sensitivity (24%) and high specificity (93%) for the diagnosis of asthma. The positive and negative likelihood ratios for the asthma diagnosis were found to be 3.2 and 0.83, respectively. CONCLUSIONS: The highest s-ECP values were found among children with moderate asthma. Animal dander allergy resulted in elevated s-ECP. However, mean values were still below the reference value of 19.1 microg/l, and the sensitivity was low, suggesting that s-ECP is not a useful parameter for diagnosing asthma in population-based studies.

Adolescent↗

Nebulized budesonide after hospitalization for recurrent bronchial obstruction in children younger than 18 months.

A multi-center, double-blind, randomized dose-response study was performed to assess the effect of 3 months of treatment with two different doses of inhaled nebulized budesonide in children with acute recurrent bronchial obstruction (BO) causing hospitalization. Steroid-naive children younger than 18 months were included when admitted to hospital because of BO for at least the second time, and were followed-up monthly for 15 months. Forty-five of 49 subjects (43 boys, 2 girls) (mean age 9.3 months upon inclusion) completed the study. Twenty-four patients (20 boys, 4 girls) received nebulized budesonide 0.5 mg twice daily for 1 month followed by 0.25 mg daily for the next 2 months, whereas 25 children received 0.1 mg twice daily throughout the 3-month treatment period. Outcome (number of BO episodes, time to first BO after start of treatment, and use of rescue medication), as well as height/length and weight, were assessed at the start of treatment and monthly for the following 3 months, as well as for 12 months after cessation of treatment (15 months in total). There was an overall tendency towards better symptom control (fewer episodes of acute BO during treatment and follow-up, fewer hospital visits because of acute BO, lower clinical score during follow-up, and less use of rescue medication during follow-up) in the high-dose treatment group vs. the low-dose treatment group. However, the differences did not reach statistical significance for any of the outcomes. The only significant difference in effect between the groups was fewer children in the high-dose group treated openly with nebulized budesonide during follow-up. Length/height and weight gain did not differ significantly between the two treatment groups throughout the study. There was no significant dose-dependent beneficial effect of 3 months of treatment with nebulized budesonide in infants and toddlers with at least two hospitalizations for acute bronchial obstruction.

Administration, Inhalation↗

Can asthma treatment in sports be doping? The effect of the rapid onset, long-acting inhaled beta2-agonist formoterol upon endurance performance in healthy well-trained athletes.

Inhaled beta2-agonists have been subject to restrictions in relationship to sports due to fear of possible improvement in endurance performance. According to the international doping regulations only inhaled salbutamol, terbutaline and salmeterol are allowed for use in sports. Formoterol is a recently introduced rapid onset-long-acting inhaled beta2-agonist. The main aim of the present randomized, double-blind placebo-controlled study was to investigate possible improvement in endurance performance of inhaled formoterol in 24 healthy well-trained competitive male athletes, 21-29 years old. Lung function (flow-volume loops) was measured before, 15 min after each inhaled study drug and before and repeatedly after exercise. On day 1, maximum oxygen uptake (VO2max), peak ventilation (VEpeak) and running time till exhaustion were measured and used to determine the exercise load on days 2 and 3. On days 2 and 3 the subjects inhaled the study drugs, rested for 1 h, then exercised, and VO2max, VEpeak and running time until exhaustion were determined. Inhaled formoterol did not improve any parameter of endurance performance. On the other hand a statistically significant, although not clinically significant (0.05 ml(-1) min kg(-1)), change was found in estimated difference of VO2max between formoterol and placebo in favour of placebo. Lung function increased significantly after inhaled formoterol, and after exercise also for placebo, but without differences between the beta2-agonist and placebo after exercise. In conclusion, inhaled formoterol did not improve endurance performance compared to placebo.

Administration, Inhalation↗

Increased level of bronchial responsiveness in inactive children with asthma.

We estimated the association between bronchial responsiveness and hours of exercise per week in children with and without asthma. A random sample of school children (n = 2188), 6-16 years old, was enrolled in a cross-sectional study of asthma in Oslo using the ISAAC questionnaire. Lung function and bronchial responsiveness (BR) using methacholine was measured in a random sample of 80 children with asthma, wheeze and no asthma/no wheeze. The relation between hours of exercise per week and BR [log (DRS)] was estimated by linear regression. Sex and age were included as covariates. Hours of exercise were categorized in: none, 30 min, 1 h, 2-3 h, 4-6 h and 7 h or more. The mean values of log (DRS) were different in the low and high exercise groups for children with asthma (P = 0.02), whereas there was no effect of exercise on BR for children without asthma. BR increased with decreasing hours of exercise per week in children with asthma. The bronchial responsiveness decreased with 0.11 (95% CI -0.20, -0.01) pr unit in scale. This pattern was not present in children without asthma. The results suggest that there is a relation between hours of exercise per week and bronchial responsiveness in children with asthma.

Adolescent↗

Lung function in children with Duchenne's muscular dystrophy.

Duchenne's muscular dystrophy (DMD), characterized by gradually developing muscular weakness, leads to respiratory symptoms and reduced lung function. We aimed to assess lung function in 25 patients with DMD in relationship to age and muscular function. The 25 boys, mean age 13 years, comprized patients in southern Norway with DMD, taking part in an epidemiological follow-up study. None had chronic respiratory disease. Lung function was measured by maximum expiratory flow-volume loops and whole body plethysmography, and repeated after 1 year (n= 14). Lung function was reduced compared to predicted values for healthy children. Forced expiratory volume in 1 sec (FEV1)% predicted and forced vital capacity (FVC)% predicted correlated (significantly) inversely to age. FEV1 and FVC decreased annually 5.61 and 4.2% of predicted, respectively. Absolute values of FVC (litres) and FEV1 (1 sec(-1)) increased until mean age 14 years, decreasing thereafter. Values in % predicted decreased steadily throughout the age range (6-19 years). Lung function correlated closely to upper limb muscle function.

Adolescent↗

Effects of maternal and early tobacco exposure on the development of asthma and airway hyperreactivity.

In 1999 a comprehensive review was published in Thorax that evaluated the role of exposure to tobacco smoke products (TSPs) in respiratory disease. The present review addresses papers published within the past 12 months on the effects of TSPs on childhood asthma and atopic disease, along with a few reports on possible mechanisms by which TSPs exert their adverse effects. Most of the observational studies published during the past year support the conclusion that both in-utero and, to some degree, passive (environmental) tobacco smoke (ETS) exposure adversely affect pulmonary function, and predispose to asthma symptoms and possibly bronchial hyperresponsiveness in childhood, but play little or no role in atopy development. However, in TSP-induced pulmonary disease, a mechanism of upregulation of pulmonary neuroendocrine cells has been hypothesized. An interventional study clearly demonstrated a need for a total (instead of partial) ban on indoor smoking in the homes of children with asthma in order to achieve significant reductions in levels of urinary cotinine. Because there is a large body of evidence for adverse effects of in-utero TSP as well as ETS exposure on respiratory health in children, we are in dire need of studies to elucidate when TSP exposure causes most damage, the mechanisms that underlie this damage, and how we can prevent unnecessary harm to the respiratory system in the vulnerable child.

Asthma↗

Lung function measurements in young children with spinal muscle atrophy; a cross sectional survey on the effect of position and bracing.

BACKGROUND: Spinal muscular atrophy (SMA) affects respiratory muscles, which in addition to progressive scoliosis leads to respiratory impairment. Children with developing scoliosis are usually treated with spinal bracing to delay the progress. AIMS: To assess the impact of body position and application of spinal bracing on lung function during tidal breathing in children with SMA. METHODS: Lung function was determined by tidal flow volume loops and passive respiratory mechanics (single breath occlusion technique) in all eight children in southern Norway with SMA type I and II, in both the sitting and supine position. Additional measurements were performed with and without bracing in five children. Muscle strength was assessed by the Brooks scale. RESULTS: Tidal expiratory volume (V(E)) and compliance of the respiratory system (CRS) tended to be higher in the sitting compared to the supine position, but this was not statistically significant. However, applying bracing in the sitting position significantly reduced V(E). The highest values of CRS and V(E) were found in the sitting position without bracing. CONCLUSION: Impairment of tidal respiration must be considered when applying spinal bracing in very young children developing scoliosis with SMA.

Braces↗