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Biomedical subjects

C S Ulrik

Publications and source records attributed to C S Ulrik.

At least 37 records · Page 2Linked to original sources
PubMed1999

A randomized clinical trial of alpha(1)-antitrypsin augmentation therapy.

We have investigated whether restoration of the balance between neutrophil elastase and its inhibitor, alpha(1)-antitrypsin, can prevent the progression of pulmonary emphysema in patients with alpha(1)-antitrypsin deficiency. Twenty-six Danish and 30 Dutch ex-smokers with alpha(1)-antitrypsin deficiency of PI*ZZ phenotype and moderate emphysema (FEV(1) between 30% and 80% of predicted) participated in a double-blind trial of alpha(1)-antitrypsin augmentation therapy. The patients were randomized to either alpha(1)-antitrypsin (250 mg/kg) or albumin (625 mg/kg) infusions at 4-wk intervals for at least 3 yr. Self-administered spirometry performed every morning and evening at home showed no significant difference in decline of FEV(1) between treatment and placebo. Each year, the degree of emphysema was quantified by the 15th percentile point of the lung density histogram derived from computed tomography (CT). The loss of lung tissue measured by CT (mean +/- SEM) was 2.6 +/- 0.41 g/L/yr for placebo as compared with 1.5 +/- 0.41 g/L/yr for alpha(1)-antitrypsin infusion (p = 0.07). Power analysis showed that this protective effect would be significant in a similar trial with 130 patients. This is in contrast to calculations based on annual decline of FEV(1) showing that 550 patients would be needed to show a 50% reduction of annual decline. We conclude that lung density measurements by CT may facilitate future randomized clinical trials of investigational drugs for a disease in which little progress in therapy has been made in the past 30 yr.

Double-Blind Method↗
PubMed1998

[Risk factors for the development of asthma in children and adolescents. Results of a longitudinal study].

To investigate risk factors for the development of asthma, a population sample of children and adolescents, aged 7 to 17 yrs at enrollment, were studied twice, with a six year interval; complete data was available for 408 subjects (199 males). Obtained case history was used to assess the presence of asthma; pulmonary function, skin prick test reactivity, total serum IgE and bronchial responsiveness to inhaled histamine (BHR) were measured using standard techniques. The 12-month period prevalence of asthma increased significantly from the first to the second examination in both males (p < 0.001) and females (p < 0.001), whereas the number of subjects with a positive histamine challenge test declined in both sexes. The prevalence of a positive skin prick test was higher at the second examination (26% and 44%, respectively, p < 0.001); the proportion of subjects with a positive skin reaction to house dust mite (HDMpos) increased from 14% to 26%. Confining the analysis to subjects without a history of asthma at the first examination showed that asymptomatic BHR (Odds Ratio [OR] 3.8 [95% Confidence Interval (CI) 2.5-5.1], p = 0.0002), HDMpos (OR 2.6 [CI 1.9-3.3], p = 0.005), a history of wheezy bronchitis before the age of two yrs (OR 3.8 [CI 2.4-5.2], p = 0.006) and a history of rhinitis and/or eczema (OR 2.8 [CI 1.7-3.9], p = 0.007) at first examination were associated with an increased risk for development of symptomatic asthma at some point between the two examinations. No significant relationship could be demonstrated between smoking (passive or active) and the risk for development of asthmatic symptoms. In conclusion, this longitudinal population study showed an increase in the 12-month period prevalence of asthma with sensitization to HDM and asymptomatic BHR as important risk factors for development of asthma.

Adolescent↗
PubMed1998

Eosinophils and pulmonary function: an epidemiologic study of adolescents and young adults.

BACKGROUND AND OBJECTIVE: In order to identify potential risk factors, other than cigarette smoking, for lung function impairment, the relationships of peripheral eosinophil count, bronchial responsiveness to inhaled histamine, skin test reactivity and respiratory symptoms to pulmonary function results in a population sample of 665 adolescents and young adults, aged 13 to 23 years. METHODS: Case history, especially concerning smoking habits and respiratory symptoms, was obtained by interview and a self administered questionnaire. Pulmonary function, peripheral blood eosinophil counts, bronchial responsiveness to inhaled histamine and skin test reactivity to common allergens were measured using standard techniques. The relationships of peripheral blood eosinophil counts, symptoms of asthma, cigarette smoking, bronchial responsiveness and skin test reactivity were compared with FEV1, adjusted for age, sex, and height. RESULTS: The peripheral eosinophil count was inversely correlated to FEV1 %predicted (P = .001); and subjects with eosinophilia (defined as > .25 x 10(9) l(-1)) had significantly reduced FEV1 %predicted compared with those without eosinophilia (95 +/- 13 %pred and 102 +/- 16 %predicted, respectively, P = .001). A close direct correlation was observed between blood eosinophils and histamine responsiveness (r = .60; P < .001). In nonatopic subjects (n = 382), the FEV1 %predicted was significantly lower in those with eosinophilia compared with those without. Subjects, who had never smoked, who were nonatopic and nonasthmatic, and who had no evidence of bronchial hyperresponsiveness, were found to have a weak but statistically significant inverse relation between eosinophil count and FEV1 %predicted (r = -.14, P = .04). In the same subgroup, subjects with eosinophilia (n = 27) had reduced FEV1 %predicted compared with those without (n = 177) (96 and 102, respectively, P < .05). CONCLUSIONS: The findings of this study support the theory that the role of the eosinophil leukocyte in obstructive pulmonary diseases extends beyond its role in allergic reactions, suggesting that an increased number of blood eosinophils reflects an inflammatory reaction in the airways, which might lead to development of obstructive airflow limitation.

Adolescent↗
PubMed1998

Long-range correlations of serial FEV1 measurements in emphysematous patients and normal subjects.

In obstructive lung disease the annual change in lung function is usually estimated from serial measurements of forced expiratory volume in 1 s (FEV1). Frequent measurements in each patient may not improve this estimate because data are not statistically independent; i.e., the measurements are autocorrelated. The purpose of this study was to describe the correlation structure in time series of FEV1 measurements. Nineteen patients with severe alpha1-antitrypsin deficiency (phenotype PiZ) and moderate to severe emphysema and two subjects with normal lungs were followed for several years with daily self-administered spirometry. FEV1 measurements fulfilling standard criteria were detrended, and the autocorrelation profile and the power spectrum were calculated. On average the subjects were followed for >3 yr and performed >1,000 acceptable spirometries. The autocorrelation of FEV1 measurements in the emphysematous patients was approximately 0.35 for short intervals and decreased almost exponentially with a half time of 38 days. Between 3 and 4 mo, the autocorrelation function became negative. It reached a minimum of -0.1 at approximately 8 mo and then increased toward zero over the following 12 mo. The autocorrelation function in the two normal subjects showed a similar pattern, but with a faster decay toward zero. In the patients, the power spectrum had a peak at 1 cycle/wk and showed a 1/f pattern, where f is frequency, with a slope of -0.88 at lower frequencies. We conclude that serial spirometric measurements show long-range correlations. The practical implication is that FEV1 need not be measured more often than once every 3 mo in studies of the long-term trends in lung function.

Adult↗
PubMed1998

Fibrous pleural tumour producing 171 litres of transudate.

Localized fibrous tumours of the pleura (or localized benign mesothelioma) are rare, and in most cases, asymptomatic. This report describes a 48 yr old female with a right-sided fibrous pleural tumour, which produced 171 L of transudate before a correct diagnosis was reached. The tumour was surgically removed and the transudation stopped immediately.

Female↗
PubMed1998

Longitudinal determinants of bronchial responsiveness to inhaled histamine.

BACKGROUND AND STUDY OBJECTIVE: The point prevalence of bronchial hyperresponsiveness (BHR) is imperfectly associated with current asthma, possibly due to changes over time in bronchial responsiveness (BR). To evaluate cross-sectional and longitudinal determinants of BR, a population sample comprising 408 children and adolescents, aged 7 to 17 years at enrollment, was examined twice, 6 years apart. METHODS: Case history was obtained by interview and questionnaire. BR to inhaled histamine, pulmonary function, and skin prick test reactivity were measured using standard techniques. RESULTS: The point prevalence of BHR (the concentration of histamine causing a 20% decline in FEV1 <8 mg/mL) declined from childhood to early adulthood (25% and 6%, respectively; p<0.001); and similarly a decline in histamine dose-response slope was observed. At both surveys, prechallenge FEV1 percent predicted, asthma, and atopy, especially atopy to house dust mite (HDM), were important determinants for the degree of BR. After adjustment for prechallenge FEV1 percent predicted, no male-female difference was observed in degree of BR. Lower FEV1 percent predicted (p=0.003), asthma (p<0.001), higher degree of BR (p=0.003), and atopy to HDM (p=0.007) at enrollment predicted a higher degree of BR at the second survey (degree of BR at second survey adjusted for prechallenge FEV1). Furthermore, new asthma (p<0.001) and/or atopy to HDM (p=0.003) were associated with higher BR at the second survey. Confining the analysis to nonasthmatics showed that subjects with new or persistent atopy to HDM had significantly increased BR compared with nonatopic subjects; and, moreover, prechallenge FEV1 percent predicted was significantly correlated with BR. CONCLUSIONS: BR declines from childhood to early adulthood, possibly reflecting the increase in airway caliber. The level of FEV1 and atopy, especially to HDM, are important determinants for changes over time in level of BR, also in nonasthmatic subjects.

Administration, Inhalation↗
PubMed1997

[Mortality in adults with asthma. Results from the Osterbro study].

A prospective analysis of overall and cause-specific mortality in subjects with self-reported asthma was undertaken using the data from The Copenhagen City Heart Study. A sample of 13,540 individuals selected from the general population was followed for 17 years. Survival of subjects with self-reported asthma was significantly poorer than that of non-asthmatics, the excess mortality being limited to pulmonary mortality. After statistical adjustment for age, length of school education, and smoking, women with asthma had a 1.7 higher risk of dying than women without asthma. The similar risk for men was 1.5. Inclusion of one-second forced expiratory volume, in % predicted, in the mortality analyses showed that the increased risk of death associated with asthma was mediated mainly through reduced lung function. We conclude that in the general population self-reported asthma is associated with a slight excess of mortality, mainly due to respiratory disease.

Adult↗
PubMed1997

Iron status in young Danes. Evaluation by serum ferritin and haemoglobin in a population survey of 634 individuals aged 14-23 yr.

Iron status was assessed by serum ferritin and haemoglobin in a population survey comprising 634 randomly selected urban Danes (312 males, 322 females) 14-23 yr old. At all ages, males had significantly higher serum ferritin and haemoglobin values than females. Males: median serum ferritin displayed a steady increase with age from 33 to 109 micrograms/l (rs = 0.53, p < 0.0001). The prevalence of absent mobilizable body iron stores (serum ferritin < 13 micrograms/l) was 3.5% at 16-17 yr of age, gradually declining to 0% at 22-23 yr. None of the males had iron deficiency anaemia (serum ferritin < 13 micrograms/l and haemoglobin < 129 g/l). Females: median ferritin values displayed a slight increase with age from 28 to 39 micrograms/l (rs = 0.19, p < 0.001). The prevalence of absent iron stores was 12.5% at 16-17 yr of age, declining to 6.6% at 22-23 yr. The prevalence of iron deficiency anaemia (serum ferritin < 13 micrograms/l and haemoglobin < 121 g/l) was 4.7% at 16-17 yr of age, declining to 1.3% at 22-23 yr of age. Compared with surveys in other parts of Scandinavia, young Danes had slightly higher serum ferritin levels, and a lower prevalence of iron deficiency.

Adolescent↗
PubMed1997

Published models and local data can bridge the gap between reference values of lung function for children and adults.

The aim of this study was to create reference equations for pulmonary function tests (PFTs) that span the age range from childhood to young adulthood. PFT results (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), ratio of FEV1 to FVC (FEV1/FVC), total lung capacity (TLC), transfer factor) of 348 healthy 13-24 yr old Caucasian never-smokers from a local population study were compared with 13 selected sets of published reference equations. Predicted and observed PFT results differed significantly for 63 of 92 reference equations tested, and most equations accounted poorly for the increase in PFT variables which takes place during adolescence. We selected the equations with the best fit and adjusted their parameters, so that the level and variance of predicted values agreed with the local data. For subjects older than 18 yrs, we selected the European Community for Steel and Coal (ECSC) equations. For subjects younger than 18 yrs, we chose European summary equations for FVC, FEV1, and FEV1/FVC, and recent British equations for TLC and transfer factor. The customized reference equations are the best available (maximum likelihood) for analysing PFTs of patients tested in our laboratory. Our approach can be used whenever generally accepted reference equations are lacking and a local sample of normal subjects is available.

Adolescent↗
PubMed1996

[The effect of salmeterol in the treatment of smokers with chronic obstructive lung disease].

Patients with chronic obstructive pulmonary disease (COPD) may benefit from long term treatment with bronchodilators despite having a modest acute response to these drugs. To investigate the efficacy of salmeterol in smokers with COPD a double blind, randomised, crossover comparison was performed between salmeterol (50 micrograms twice daily) and placebo in 63 patients with stable COPD (mean age 63 yrs); inclusion criteria: aFEV1) < 60% of predicted and FEV1 reversibility < 15% (0.4 mg salbutamol). Patients received four weeks of therapy with each of the treatment regimens. Assessment of efficacy was done by recording morning and evening peak expiratory flow rates (PEF), respiratory symptoms, and use of rescue salbutamol. Morning PEF values were higher during the salmeterol than during the placebo period, although the mean treatment difference was small (12 l/min (95% confidence limits 6 to 17)). No difference in mean evening PEF values was found. Diurnal variation in PEF was more pronounced during the placebo than during the salmeterol period. Compared with placebo, treatment with salmeterol was associated with lower day time and night time symptom scores and less use of rescue salbutamol both during the day and the night. This study shows that, compared with placebo, treatment with salmeterol produces an improvement in respiratory symptoms and morning PEF values in patients with moderate to severe COPD. Treatment with long acting beta(2)-agonists may therefore result in an improvement in functional status, even in patients suffering from apparently non-reversible obstructive pulmonary disease.

Adrenergic beta-Agonists↗
PubMed1996

[Mortality and fatal risk factors in 1075 outpatients treated for asthma].

Mortality and markers of risk of death from asthma were studied among 1,075 astmathics attending a chest clinic in Copenhagen between 1974 and 1990; they were compared with a sex- and age-matched group of non-asthmatic patients. Both groups comprised 425 males (mean age 37 yrs (SD 15)) and 650 females (mean age 39 yrs (SD 16)) and the mean follow up period was 8.6 yrs (SD 4.2). Mortality from all causes was significantly increased in the asthmatic subjects (93 deaths) compared to the control group (41 deaths); relative risk (RR) 2.4, (95% confidence interval (CI) 1.6 to 3.4). The predominant cause of excess mortality was obstructive pulmonary disease, that is, status asthmaticus (14 vs. 0 deaths, RR 8.2) and chronic asthma (19 vs. 0 deaths, RR 8.3). Mortality analysis employing the multiple regression model of Cox revealed that age, pack-years of smoking, eosinophilia, level of FEV1% pred and degree of reversibility in FEV1 were significant predictors of death from asthma. In subjects with eosinophilia (> 0.45 mia/l), the risk of dying from asthma was 7.4 (CI 2.8-19.7) greater than in those without eosinophilia. Compared to subjects with 15-24% reversibility in FEV1, the subjects with 25-49% and > 50% reversibility had a 2.7 and 7.0 higher risk of death from asthma, respectively. Mortality was significantly increased in asthmatics compared to matched controls, primarily due to death from acute and chronic asthma. Furthermore, the present findings suggest that eosinophilia and pronounced increase in FEV1 following bronchodilator are strong markers of subsequent risk of death from asthma.

Adult↗
PubMed1996

[Eosinophil count in asthma. A marker of disease activity in intrinsic and extrinsic asthma].

The relationship between eosinophil count and pulmonary function (FEV1), respiratory symptoms, bronchial responsiveness to histamine and diurnal variation in peak expiratory flow rate (PEF) was studied in a group of asthmatics (n = 70) examined in childhood (mean age 10 yrs) and early adulthood (mean age 21 yrs), of whom 24 had intrinsic and 46 extrinsic asthma. Self-reported symptoms of asthma were graded on a scale from zero to five; histamine responsiveness was analysed by means of the dose-response slope (DRS). In both childhood and adulthood, a direct correlation was found between blood eosinophil count and symptom score (r = 0.69, p < 0.001 and r = 0.58, p < 0.001, respectively), whereas inverse correlations were observed between number of eosinophils and FEV1 expressed as percentage of predicted values (r = -0.75, p < 0.001 and r = -0.80, p < 0.001, respectively). Furthermore, in adulthood, eosinophil count was found to be significantly correlated to histamine responsiveness (logDRS) (r = 0.65, p < 0.001) and diurnal PEF variation (r = 0.81, p < 0.001); these correlations were also noted after dividing the subjects into intrinsic and extrinsic asthmatics. The findings in the present study suggest that the peripheral eosinophil count reflects asthmatic activity, and possibly the degree of inflammation in the airways, in both children and young adults.

Adolescent↗
PubMed1996

[Extrinsic and intrinsic asthma from childhood to early adult age. A 10-year follow-up].

The purpose of this study was to describe factors of potential importance for the outcome in children with intrinsic and extrinsic asthma. Of 85 consecutive children, five to 15 years of age, with asthma, 70 (82%) participated in a ten year follow up examination. At the time of referral all children underwent certain tests for asthma (case history, total IgE, skin prick tests, radioallergosorbent tests (RAST) and specific bronchial provocations). On the basis of these tests 24 children had intrinsic asthma and 46 extrinsic asthma. At the follow up examination 60 of the 70 adults (86%; 20 with intrinsic asthma) had current symptoms; 54 of the 60 (90%; 18 with intrinsic asthma) were receiving maintenance therapy. Both FEV1 %pred (from 73% +/- 19% to 92% +/- 17%) and FEV1/FVC (from 75% +/- 13% to 80% +/- 12%) increased significantly from childhood to early adulthood (p < 0.0002 and p < 0.001, respectively); a corresponding amelioration of symptoms was also observed (p < 0.0001). In children with intrinsic asthma the outcome seems to be predicted by a combination of the initial frequency of symptoms (p = 0.04), initial FEV1 (p = 0.001), active smoking (p = 0.001) and age at onset of respiratory symptoms (p = 0.001), whereas the initial FEV1 (p < 0.001) seems to be a strong predictor for the outcome in children with extrinsic asthma. These findings suggest that the pathogenetic mechanisms underlying intrinsic and extrinsic asthma in children may differ.

Adolescent↗
PubMed1996

[Early diagnosis of amiodarone-induced pulmonary toxicity: are repeated lung function tests of any value?].

Amiodarone therapy for certain life-threatening cardiac arrhythmias is associated with numerous side and adverse effects, of which pulmonary toxicity is one of the most serious adverse reactions. It appears to be generally accepted that amiodarone-induced pulmonary toxicity (APT) is associated with considerable morbidity and mortality. Based on the assumption that detection of APT in an asymptomatic phase would improve the prognosis for these patients, the value of monitoring for toxic effects with various paraclinical tests has been extensively studied. This article summarizes current knowledge of the pulmonary complications of amiodarone therapy with emphasis on the usefulness of pulmonary function tests in the detection of APT. Based on the findings in the published studies, it appears that changes in pulmonary function, including diffusion capacity, over time do not identify patients at risk for development of APT. It is suggested that it is worthwhile to obtain two or three measurements of pulmonary function, including diffusion capacity, within the first few months of therapy in order to establish the variation in the individual patient. When a stable maintenance dose has been reached, subsequent testing should be reserved for patients who develop new or progressive pulmonary symptoms or radiographic infiltrates.

Amiodarone↗
PubMed1996

Mortality in adults with self-reported asthma. Copenhagen City Heart Study Group.

BACKGROUND: On the question of whether asthma shortens survival the published work gives no clear answer. We have prospectively analysed overall and cause-specific mortality in persons with self-reported asthma. METHODS A sample of 13 540 individuals (6104 men) 20 years of age or older, randomly selected from the general population of the city of Copenhagen, was followed for 17 years. FINDINGS: Survival in participants with self-reported asthma was significantly poorer than in non-asthmatics, the excess mortality being limited to pulmonary mortality. After statistical adjustment for age, length of school education, and smoking, women with asthma had a 1.7 higher risk of dying than women without asthma (95% confidence interval 1.3--2.2). Although the relative risk (RR) of dying with asthma was slightly lower in men (RR = 1.5, 95% Cl 1.2-1.9) the difference between sexes was not significant. The results were similar within smoking groups and the highest risk of death associated with asthma was seen among never-smokers (RR = 2.1, 95% Cl 1.6-2.3). Inclusion of one-second forced expiratory volume, in % predicted, in the mortality analyses showed that the increased risk of death associated with asthma was mediated mainly through reduced lung function. INTERPRETATION: We conclude that, in the general population, self-reported asthma is associated with a slight excess of mortality, mainly from respiratory diseases.

Adult↗
PubMed1996

Factors associated with increased bronchial responsiveness in adolescents and young adults: the importance of adjustment for prechallenge FEV1.

BACKGROUND: Asymptomatic increased bronchial responsiveness (BR) appears to be a major risk factor for later development of asthma, but risk factors for increased BR are not well established. OBJECTIVE: The relationship of age, gender, house dust mite allergy, number of blood eosinophils, and FEV1 to the degree of nonspecific BR was studied in a population sample of 665 adolescents and young adults, aged 13 to 23 years. METHODS: Case history, especially concerning smoking habits and respiratory symptoms, was obtained by interview and a self-administered questionnaire. Pulmonary function, number of blood eosinophils, BR to inhaled histamine, and skin test reactivity to house dust mites were measured with standard techniques. BR was analyzed as both a continuous variable (dose-response slope) and a categorical variable (cutoff: PC20 16 mg/ml). RESULTS: Increasing number of blood eosinophils, sensitivity to house dust mite, and former or current symptoms of asthma were associated with increasing levels of BR, independently of the level of FEV1. Adjustment for prechallenge FEV1 revealed a strong association between lower prechallenge FEV1 and increasing level of BR (p less than 0.0001), whereas the previously observed association between female gender and higher level of BR vanished. Repeating the analyses after exclusion of subjects with former or current asthma (n = 85) showed an unchanged relationship between house dust mite allergy and level of BR whether or not prechallenge FEV1 was included in the regression model, whereas gender only influenced the level of BR when no adjustment was made for prechallenge FEV1. On the contrary, the number of blood eosinophils was only significantly associated with BR after adjustment for baseline FEV1. Comparable findings were observed when patients with former or current symptoms of asthma and subjects with a prechallenge FEV1 less than 80% of predicted value (n = 46) were excluded from the analyses. CONCLUSIONS: This analysis suggests that adjustment for prechallenge level of FEV1 should be considered in studies concerned with risk factors for symptomatic and asymptomatic bronchial hyperresponsiveness.

Adolescent↗
PubMed1996

Risk factors for development of asthma in children and adolescents: findings from a longitudinal population study.

BACKGROUND: The prevalence of asthma appears to be on the increase, and risk factors are not well established. To investigate risk factors for the development of asthma, a population sample of children and adolescents, aged 7-17 years at enrolment, were studied in 1986. Initial examinations were repeated at follow-up in 1992; complete data was available for 408 subjects (199 males). METHODS: Obtained case histories were used to assess the presence of asthma; pulmonary function, skin prick test reactivity, total serum IgE and bronchial responsiveness to inhaled histamine were measured using standard techniques. RESULTS: The 12-month period prevalence of asthma increased significantly from the first to the second examination in both males (P < 0.001) and females (P < 0.001), whereas the number of subjects with a positive histamine challenge test declined in both sexes, although this was only statistically significant in males (P < 0.001). The prevalence of a positive skin prick test was higher at the second examination (26% and 44%, respectively, P < 0.001); the proportion of subjects with a positive skin reaction to house dust mite (HDM pos) increased from 14% to 26%. Bronchial hyper-responsiveness to inhaled histamine (BHR), HDM allergy, a history of wheezy bronchitis and symptoms of asthma at first examination were more prevalent among subjects reporting asthma at the second examination than among subjects without respiratory symptoms. Confining the analysis to subjects without a history of asthma at the first examination showed that asymptomatic BHR ¿Odds ratio [OR] 3.8 [95% confidence interval (CI) 2.5-5.1], P = 0.0002¿, HDM pos [OR 2.6 (95% CI 1.9-3.3), P = 0.005], a history of wheezy bronchitis before the age of 2 years [OR 3.8 (95% CI 2.4-5.2), P = 0.006] and a history of rhinitis and/or eczema [OR 2.8 (95% CI 1.7-3.9), P = 0.007] at first examination were associated with an increased risk for development of symptomatic asthma at some point between the two examinations. No significant relationship could be demonstrated between smoking (passive or active) and the risk for development of asthmatic symptoms. CONCLUSIONS: In conclusion, this longitudinal population study showed an increase in the 12-month period prevalence of asthma with sensitization to HDM and asymptomatic BHR as important risk factors for development of asthma; the temporal relationship between sensitization to HDM and presence of airway abnormalities needs to be explored further.

Adolescent↗