Participants
Those of working age (40-65 years: n~760) in the COPD cohort are eligible for cross-sectional analysis, and a subset (those in paid employment at baseline n~200) for the longitudinal analyses.
Exposures
These will be collected at baseline within the cohort study using validated measures, including:
•Demographic information (age, sex, socioeconomic status)
•Disease severity (lung function, smoking history, comorbidities),
•Occupation.
During follow up of patients in work, information on exacerbations, change in treatment and symptoms, and change in lung function from baseline to follow up will also be collected.
Outcomes
The following data will be obtained by self-report at baseline:
1. Employment status
2. Absenteeism: self-reported absenteeism over the last 12 months
3. Presenteeism
The absenteeism and presenteeism questionnaires will be re-administered 6-monthly to the subset of the cohort in employment at baseline, in addition to the other measures recorded in the whole cohort. There is some evidence that presenteeism scores can change over time, in response to interventions and this project will provide further information on its use in this context.
Analysis
Cross-sectional:
The relationship between COPD severity, sociodemographic factors, other health status measures, occupation and the outcomes of interest (employment status, presenteeism score and absenteeism) at baseline will be described. Multivariable analyses will be used to examine the relationship between disease severity and outcomes, adjusting for the other factors if relevant.
Longitudinal:
Experience of disease severity (e.g. frequency of exacerbations, need for medications) in relation to patterns of absenteeism/presenteeism will be assessed. A labour market analysis model will also be used to explore which are the main determinants of working and whether they may be modifiable.