Lung function in Lolland-Falster Health Study (LOFUS).

Area of Science:

• Pulmonary Medicine
• Epidemiology
• Respiratory Health

Background:

• Chronic Obstructive Pulmonary Disease (COPD) prevalence in Denmark is estimated at 18% from urban data.
• Clinical cut-offs for airway obstruction may overestimate prevalence in population studies.
• Lung function data from a rural Danish population (Lolland-Falster Health Study) is presented.

Purpose of the Study:

• Compare estimated prevalence of airway obstruction using different spirometry cut-offs.
• Present lung function data from a rural-provincial Danish population.
• Investigate the impact of diagnostic criteria on COPD prevalence estimates.

Main Methods:

• Descriptive analysis of participant characteristics, respiratory disease history, and spirometry results.
• Airway obstruction assessed using Danish reference values.
• Defined obstruction by FEV1/FVC < 70%, FEV1/FVC < LLN 5%, or FEV1/FVC < LLN 2.5%.

Main Results:

• 19.0% prevalence of airway obstruction using FEV1/FVC < 70% or LLN 5% cut-offs.
• 12.2% prevalence using the LLN 2.5% criterion.
• Higher prevalence in smokers, those with less education, low physical activity, or known respiratory disease; 40% with known disease had normal spirometry.

Conclusions:

• Rural COPD prevalence comparable to urban estimates, but cut-off choice is critical.
• The FEV1/FVC < 70% criterion may overestimate airway obstruction prevalence.
• A significant proportion of individuals with known respiratory disease showed normal spirometry results.