Calculating gambling odds and lung ages for smokers

Area of Science:

• Pulmonary Medicine
• Public Health
• Biostatistics

Background:

• Interpreting spirometry using standard confidence limits can mask subtle airflow reductions.
• Alternative analytical approaches may be more effective in encouraging smokers to cease smoking.

Purpose of the Study:

• To determine the odds that specific spirometric ratios (%FEV(1)/FEV(6) and %FEV(1)/FVC) originate from current or never-smokers across different age groups and ethnicities.
• To develop simplified formulas for estimating physiological lung age changes (Deltalung age) in males and females.

Main Methods:

• Analysis of high-quality spirometric data from over 9000 never- and current-smokers of diverse ethnicities (African, European, Latin-American) from NHANES III.
• Calculation of odds ratios for %FEV(1)/FEV(6) and %FEV(1)/FVC by decade of life.
• Development and validation of new formulas for Deltalung age based on predicted and actual spirometric values.

Main Results:

• Odds of smoking-induced decreases in %FEV(1)/FEV(6) and %FEV(1)/FVC increase significantly with each decade of life.
• Simplified formulas for Deltalung age were derived: (predicted - actual) %FEV(1)/FEV(6) x 4 or (predicted - actual) %FEV(1)/FVC x 3.
• Smokers' Deltalung age increased rapidly until the sixth decade, with slower increases thereafter, potentially due to mortality or survey participation biases.

Conclusions:

• Odds ratios and Deltalung age calculations offer a potentially more persuasive method than traditional confidence limits to encourage smoking cessation.
• These novel approaches may improve the communication of smoking's detrimental effects on lung health, particularly for milder airflow decreases.