A Population-based Investigation of Asthma in the Telemark Region of Norway

Hypotheses and choice of methods: Primary objective: To identify preventive and health promoting measures for obstructive respiratory disease in a 5-year follow up of adults from the general population in Telemark. Secondary objectives: * Identify occupational risk factors for obstructive respiratory disease * Assess interactions between risk factors and the individual * Transfer relevant knowledge and advice regarding preventive and health promoting measures to individuals, health care professionals and authorities. Research problems/questions (Q): Q1 What are the emerging occupational risk factors for respiratory health? Q2 What are the social inequity/socioeconomic factors predicting respiratory disease? Q3 How does HRQoL develop over time? Q4 Do risk factors interact and how do they relate to the individual? Q5 What is the population attributable risk (PAR) for the identified risk factors, and what are the key factors for better prevention and respiratory health promotion? Choice of methods/work packages (WP) and approaches (A): WP I Occupational risk factors Q1 Emerging occupational causes and risk factors for respiratory disease and exacerbation * A1.1 Assess associations between self-report of occupational exposure and new-onset and exacerbation of respiratory symptoms and diseases * A1.2 Assess associations between job-exposure-matrix data (JEM) and new-onset and exacerbation of respiratory symptoms and diseases WP II Individual risk factors Q2 Risk factors for social inequity in respiratory health • A2.1 Assessment of the association between socio-demographic variables (gender, age, education, occupation and income) and respiratory health WP III Complex interactions Q3 Health related quality of life development over time. * A3.1 Impact of respiratory health and disease development and treatment on HRQoL development Q4 Interactions between risk factors and the individual * A4.1 Identify interactions between risk factors and the individual by using advanced mathematical modelling Q5 The population attributable risk (PAR) for identified risk factors and key factors for better prevention and respiratory health promotion * A5.1 Calculate PAR for risk factors identified in WP1-3 separately and combined * A5.2 Based on PAR, estimate key factors for prevention and their cost