Risk factors for asthma in young adults: a co-twin control study.

Background: The liability to asthma is influenced both by genetic and environmental factors. The objective of this study was to identify risk factors for asthma in young adult twin pairs during an 8-year period.

Methods: From the birth cohorts 1953-1982 of the Danish Twin Registry, 6,090 twin pairs who were initially unaffected with respect to asthma at a nationwide questionnaire-based study in 1994 participated in a similar follow-up study in 2002.

Chronic mucus hypersecretion: a marker of asthma in young adults?

Objective: To investigate if chronic mucus hypersecretion (CMH) can be used as a marker of asthma in young adults.

Study Design And Setting: Cross-sectional study of a population sample of young Danish adults (n=624, 279 males), aged 19-29 years. Case history, including tobacco exposure and respiratory symptoms, was obtained by questionnaire.

Recognition of asthma in adolescents and young adults: which objective measure is best?

Background: Objective assessment of airway function is important in epidemiologic studies of asthma to facilitate comparison between studies. Airway hyperresponsiveness (AHR), peak expiratory flow (PEF) variability, and bronchodilator reversibility (BR) are widely used as markers of airway lability in such studies. Data from a survey of a population sample of adolescents and young adults (n = 609; 288 males), aged 13-23 years, were analyzed to investigate whether AHR, PEF variability, and BR can be used interchangeably as markers of asthma in an epidemiological setting.

Outcome in adulthood of asymptomatic airway hyperresponsiveness to histamine and exercise-induced bronchospasm in childhood.

Background: Studies of the clinical outcome in adulthood of asymptomatic airway hyperresponsiveness (AHR) to histamine or exercise-induced bronchospasm (EIB) detected in childhood in general population samples are sparse and have produced conflicting results.

Objective: To describe the outcome of asymptomatic AHR to histamine and EIB.

Methods: Data from a 12-year follow-up study of a random population sample of individuals aged 7 to 17 years at enrollment were analyzed; only individuals without asthma at enrollment were included in the analysis.

Risk factors for rehospitalisation in COPD: role of health status, anxiety and depression.

The aim of the present study was to analyse the risk of rehospitalisation in patients with chronic obstructive pulmonary disease and associated risk factors. This prospective study included 416 patients from a university hospital in each of the five Nordic countries. Data included demographic information, spirometry, comorbidity and 12 month follow-up for 406 patients.

The incidence of asthma in young adults.

Study Objectives: Longitudinal data on adult asthma are sparse. The objectives of this study were to determine the incidence of asthma and to establish the risk factors for the development of asthma in subjects who were 12 to 41 years old over an 8-year period.

Design: From birth cohorts over the period 1953 to 1982 in The Danish Twin Registry, 19,349 subjects with no history of asthma, as determined by a questionnaire-based survey in 1994, answered a follow-up questionnaire in 2002.

Change in prevalence of asthma in Danish children and adolescents.

Background: There is evidence suggesting that the prevalence of asthma has increased, especially in industrialized countries.

Objective: To investigate whether the prevalence of asthma in Danish children and adolescents has changed during the past 15 years.

Methods: Serial cross-sectional studies of 2 different random population samples of children aged 7 to 17 years, living in urban Copenhagen, Denmark, were performed 15 years apart.

Factors associated with asthma in young Danish adults.

Background: The prevalence of asthma appears to be increasing, but our knowledge about factors associated with asthma in young adults is limited. Factors associated with asthma were studied in 624 (66% of those invited) young Danish adults (aged 19 to 29 years).

Objective: The purpose of this study was to investigate the prevalence and predictors of asthma in young Danish adults.

Prevalence and predictors of atopy among young Danish adults.

Background: The prevalence of atopic diseases is increasing in western countries, and environmental exposures in childhood may influence development of atopic sensitization.

Objective: To investigate the prevalence and predictors of atopy among young Danish adults.

Methods: Of 940 invited subjects, aged 19-29 years, complete data were obtained from 525 (56%) subjects.

[Smoking and asthma].

Cigarette smoking is a well-known health hazard, probably not least for patients suffering from asthma. This review gives a short overview of the effects of passive and active smoking on the inception and outcome with of longitudinal changes in the lung function and mortality of patients with asthma. Substantial evidence suggests that smoking affects asthma adversely.

[Atopy among children and adolescents in Copenhagen].

Introduction: Atopy is related to the presence of rhinitis and asthma, but our knowledge about its longitudinal predictors is limited.

Methods: Data from a 6-yr follow-up study of a population sample of children and adolescents (n = 408), aged 7 to 17 yr. at enrollment, were analysed to investigate the prevalence and predictors of atopy.

Cigarette smoking and asthma.

Cigarette smoking is a well-know health hazard, probably not least for patients suffering from asthma. This review gives a short overview concerning the effects of passive and active smoking on the inception and outcome with regard to longitudinal changes in lung function and mortality for patients with asthma. Substantial evidence suggests that smoking affects asthma adversely.

Exogenous female sex steroid hormones and risk of asthma and asthma-like symptoms: a cross sectional study of the general population.

Background: Recent evidence suggests a role for hormonal factors in the aetiology of asthma.

Methods: Data from a large study of women selected from the general population were used to relate treatment with oral hormonal contraceptives (OCP) and postmenopausal hormone replacement therapy (HRT) to the following asthma indicators: self-reported asthma, wheezing, cough at exertion, and use of medication for asthma. The study sample comprised 1536 premenopausal and 3016 postmenopausal women who participated in the third round of the Copenhagen City Heart Study in 1991-4.

Prevalence and predictors of rhinitis in Danish children and adolescents.

Background: The prevalence of self-reported symptoms of allergic rhinitis is increasing in many countries, but the reasons for this trend are not well understood. Data from a 6-year follow-up study of a population sample of children and adolescents (n=408), aged 7-17 years at enrolment in 1986, were analyzed to investigate the prevalence and predictors of self-reported rhinitis.

Methods: Case history was used to assess the presence or absence of rhinitis (sneezing and running or blocked nose not associated with a cold), asthma, and eczema.

Atopy in Danish children and adolescents: results from a longitudinal population study.

Background And Objective: Atopy is an objectively measurable trait related to the presence of rhinitis and asthma, but our knowledge about its longitudinal predictors is limited. Data from a 6-year follow-up study of a population sample of children and adolescents (n = 408), aged 7 to 17 years at enrollment, were analyzed to investigate the prevalence and predictors of atopy.

Methods: Case history, including allergic diseases and smoking habits, was obtained by interview and questionnaire.

Office spirometry: temperature conversion of volumes measured by the Vitalograph-R bellows spirometer is not necessary.

The aim of the present study was to investigate the relevance of BTPS (gas at body temperature, atmospheric pressure and saturated with water vapour) conversion of volumes measured with the Vitalograph bellows spirometer. The Vitalograph bellows were tested against a MicroMedical turbine spirometer in extreme temperatures (0-37 degrees C) using a biological control to deliver expired gas at BTPS. Before testing, it was shown that the accuracy of the DairyCard turbine was stable in the relevant temperature range.

Nonreversible airflow obstruction in life-long nonsmokers with moderate to severe asthma.

The aim of this longitudinal study was to assess the frequency of nonreversible airflow obstruction (NRAO) among adults with moderate to severe asthma, and to compare the decline of forced expiratory volume in one second (FEV1) in asthmatics with reversible and nonreversible airflow obstruction. Ninety-two (31 males) life-long nonsmokers with asthma participated in a 10-yr follow-up study; mean age 37 yrs (range 18-64) and duration of asthma 16 yrs (range 2-60) at enrolment. Case history, including use of asthma medication, was obtained, and pulmonary function, including diffusion capacity, was measured using standard techniques.

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.

A longitudinal study of serum ferritin in 319 adolescent Danish boys and girls examined in 1986 and 1992.

This study examined trends in iron status in adolescents. Serum ferritin was measured in 1986 and 1992 in 319 Danes (161 males) stratified into 5 groups: I. median age 9 yr in 1986 vs.

Pulmonary function in chronic heart failure. Changes after heart transplantation.

To investigate the impact of chronic heart failure on pulmonary function in heart transplant recipients, pulmonary function was evaluated in 41 consecutive patients (mean age 43 years, range 15-57 years) before and 6 months after successful heart transplantation. The pulmonary function tests included measurements of forced vital capacity [FVC], forced expiratory volume in 1.s [FEV1], FEV1/FVC ratio, total lung capacity [TLC], and diffusion capacity for carbon monoxide [TLCO] and KCO [TLCO per l alveolar volume].

Markers of impaired growth of pulmonary function in children and adolescents.

Our knowledge about the age-related growth of pulmonary function is incomplete. The purpose of this study was to describe the relation of various factors to the growth of pulmonary function in children and adolescents. A population sample comprising 408 children and adolescents (7-17 yr of age at enrollment) was reexamined after a 6-yr interval.