[The Austrian LEAD (Lung hEart sociAL boDy) Study: Background of the Austrian Longitudinal Cohort Study]. / The Austrian LEAD (Lung hEart sociAL boDy) Study: Die Hintergründe der österreichischen longitudinalen Kohortenstudie.

More research is needed to elucidate natural history and underlying pathomechanisms of the most common airway diseases, Asthma and COPD. In the last decade risk factors affecting the natural history of lung function, defined by the decline of lung function over time, have been evaluated. Moreover, scientific methods have been extended and novel biomarkers, genetics, metabolomics, and epidemiology are dominant tools for investigating the natural history of lung function and potential risk factors. Evidence shows that lung function in childhood is a predictor for lung function in adulthood and risk factors starting in utero contribute to lung function decline during life. Therefore, recently it has been hypothesized that COPD begins in childhood. Thus, prospective investigation of lung function changes including novel scientific methodology has been advocated. The Austrian LEAD  study has been initiated in the general population 2012 to investigate the natural history of obstructive airway diseases.

Prevalence and etiotypes of persistent airflow obstruction in the general population across the lifetime.

BACKGROUND AND OBJECTIVES: Different factors (etiotypes) can lead to persistent airflow obstruction (PAO) across the lifetime, including genetic factors, abnormal lung development, cigarette smoking, traffic pollution exposure, respiratory infections and asthma. Here we explore the prevalence of PAO and associated etiotypes in the general population in different age bins. METHODS: We studied 664 individuals with PAO (FEV1/FVC post bronchodilation (post-BD) below the lower limit of normal (LLN)) and 11,522 with normal lung function (FEV1/FVC, FEV1 and FVC ≥ LLN and ≤ upper limit of normal (ULN) post-BD) included in the LEAD Study (NCT01727518), a general population cohort in Vienna (Austria). For analysis, participants were stratified in three age bins (<25, 25-<50 and ≥ 50 years of age). RESULTS: PAO occurred in 3.8 % in females and 5.6 % in males of the cohort, and it increased with age. Most participants with PAO (57.5 %) reported respiratory symptoms, indicating a high burden of disease. PAO was associated with male sex (25-<50 years), ever smoking (>50 years), increased number of pack years (25-<50 years, >50 years), not being breastfed (<25 years) and ever diagnosis of asthma (in all age bins). Etiotypes varied by age bins with cigarette smoking being the most prevalent one, often in combination with traffic pollution exposure. CONCLUSION: In the general population PAO occurs in about 5 % of participants with a higher prevalence in older individuals. Etiotypes and associated factors for PAO accumulate with age.

Distribution of chronic cough phenotypes in the general population: A cross-sectional analysis of the LEAD cohort in Austria.

RATIONALE: Recent guidelines consider chronic cough to be a unique clinical entity with different phenotypes. We aimed to investigate them in a general population and to describe prevalence, distribution, and characteristics of these phenotypes within the Austrian general population. METHODS: From the LEAD study, a longitudinal observational population-based cohort, data from questionnaires and spirometry of 10,057 adult participants was analysed. Chronic cough was defined as coughing nearly every day during the last 12 months for at least 3 months (>12 weeks). RESULTS: The prevalence of chronic cough was 9% and increased with age. We found no sex predominance but a female preponderance (68%) in never smokers. A presumable cause was identified in 85% of which more than half (53.9%) had two phenotypes, 36.9% belonged to one only and 9.2% to three or more. Regarding the distribution of phenotypes, 40.8% were current smokers, 32.6% had an ACE inhibitor intake, 18.2% GERD, 17.6% asthmatic cough, 9.7% UACS and 28.3% other diseases associated with chronic cough. 15% had unexplained chronic cough with no identifiable phenotype. Current smoking, low socioeconomic status, obesity, COPD and obstructive sleep apnea were associated factors with chronic cough. CONCLUSION: Chronic cough is common among adults in Austria and highly prevalent in the older population. Most participants can be phenotyped with simple questionnaire-based assessment and can therefore potentially receive specific treatment without intensive clinical workup.

Incidence and outcome of weaning from mechanical ventilation according to new categories.

Weaning from mechanical ventilation was categorised as simple, difficult or prolonged by an international task force of the American Thoracic Society/European Respiratory Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine/Sociéte de Réanimation de Langue Française in 2007. This new classification has not been tested in clinical practice. The objective of the present study was to determine the incidence and outcome of weaning according to the new categories. We included medical and surgical patients who required mechanical ventilation in a prospective, multicentre, 6-month cohort study. From an initial cohort of 510 patients, 257 intubated patients started weaning. Of these patients, the cumulative incidences of simple, difficult, and prolonged weaning were 152 (59%), 68 (26%) and 37 (14%), respectively. Hospital mortality was increased in patients with prolonged (32%) but not difficult (9%) weaning in comparison with those with simple weaning (13%), overall p = 0.0205. In a multivariate logistic regression model, prolonged but not difficult weaning was associated with an increased risk of death. Ventilator-free days and intensive care unit (ICU)-free days were decreased in both difficult and prolonged weaning. In conclusion, the new weaning category prolonged weaning is associated with increased mortality and morbidity in the ICU. The new category difficult to wean was associated with increased morbidity, but not mortality.

Measuring FEV(6) for detecting early airway obstruction in the primary care setting. Quality and utility of the new PiKo-6 device.

BACKGROUND: The prevalence of asthma and chronic obstructive pulmonary disease (COPD) is high ( approximately 7.4-18%) in the general population, but less than half are diagnosed. Several studies have shown FEV(6) as a good surrogate marker for forced vital capacity (FVC) to detect airflow limitations. OBJECTIVES: The aim of this study was to evaluate if it is possible to simplify and improve the diagnosis of so far undiagnosed asthma or COPD in the primary care setting by measuring FEV(6) with a new simple screening device (PiKo-6). METHODS: 507 patients were recruited from three general practices from May to June 2005. Patients with any known pulmonary disease were excluded by questionnaire. FEV(1), FEV(6) and FEV(1)/FEV(6) were determined using a PiKo-6 device. Patients with an FEV(1)/FEV(6) <80% (PiKo positive) were invited to a standardized pulmonary function test to confirm or rule out airflow limitation. RESULTS: 401 (79.1%) patients showed FEV(1)/FEV(6) > or =80% (PiKo negative), and 106 (20.9%) patients were PiKo positive. Of the 106 PiKo-positive patients, 74 patients (14.7% of total) agreed to further studies and 18 patients (3.6%) of them suffered from COPD [COPD 0: 5 (1.0%); COPD I: 9 (1.8%); COPD II: 4 (0.8%), and none with COPD III or IV] and 14 patients (2.8%) suffered from bronchial hyperresponsiveness or asthma. In 42 patients (8.3%), the pulmonary function test was normal. CONCLUSIONS: Measurement of FEV(6) using a new simple screening device (PiKo-6) may improve the detection rate of undiagnosed airflow limitation in the primary care setting. However, patients should be carefully selected.