Physical fitness, respiratory symptoms and lung function

Area of Science:

• Pulmonary physiology
• Respiratory medicine
• Biometrics

Background:

• Established prediction equations for lung volumes (e.g., FVC1, FEV1.0, peak flow) are widely used.
• Current standards may not accurately reflect the respiratory potential of diverse populations.
• The influence of various physiological and lifestyle factors on lung function requires further investigation.

Purpose of the Study:

• To assess lung volumes in a large cohort of male and female volunteers.
• To compare measured lung function with existing prediction standards.
• To investigate the impact of factors like smoking, body composition, and self-reported respiratory symptoms on lung volumes.

Main Methods:

• Spirometry was performed on 403 men and 561 women using an SRL automated spirometer system.
• Lung volumes were compared to predicted values derived from SRL computer formulae and Anderson et al. standards.
• Multivariate analysis examined the contribution of lean mass, obesity, and Cornell Medical Index responses to lung volumes.

Main Results:

• Average lung function scores were 5-10% higher than predicted, suggesting underestimation by current standards.
• A dose-dependent decrease in lung function was observed among cigarette smokers, though no significant difference existed between smokers and non-smokers overall.
• Below-expected lung volumes were associated with positive responses to respiratory questions, particularly asthma, indicating potential for questionnaire-based screening.

Conclusions:

• Existing prediction equations for lung volumes may underestimate respiratory potential.
• Body composition (lean mass, obesity) has a statistically significant but not practically large effect on lung volumes.
• Improved respiratory questionnaires show promise for pulmonary screening, potentially offering greater value than solely relying on expensive spirometry equipment.