Morris et al compared a patient's spirometric values to population norms to describe a "lung age." This can help to demonstrate to a smoker the impact of smoking and the need to quit. The authors are from the Veterans Administration Medical Center in Portland, Oregon.
Parameters:
(1) gender
(2) height in inches
(3) FVC (forced vital capacity) in liters
(4) FEV1 in liters
(5) FEF(200-1200) in liters per second (mean forced expiratory flow between the 200 and 1200 mL of the FVC)
(6) FEF(25-75%) in liters per second (mean forced expiratory flow during the middle half of the FVC)
Lung Age Equations for Males
lung age in years for male based on FVC =
= (5.920 * (height in inches)) - (40 * (FVC)) - 169.64
lung age in years for male based on FEV1 =
= (2.870 * (height in inches)) - (31.25 * (FEV1)) - 39.375
lung age in years for male based on FEF200_1200 =
= (2.319 * (height in inches)) - (21.277 * (FEF200_1200)) + 42.766
lung age in years for male based on FEF25%_75% =
= (1.044 * (height in inches)) - (22.222 * (FEF25%_75%)) + 55.844
Lung Age Equations for Females
lung age in years for female based on FVC =
= (4.792 * (height in inches)) - (41.667 * (FVC)) - 118.833
lung age in years for female based on FEV1 =
= (3.560 * (height in inches)) - (40 * (FEV1)) - 77.28
lung age in years for female based on FEF200_1200 =
= (4.028 * (height in inches)) - (27.778 * (FEF200_1200)) - 70.333
lung age in years for female based on FEF25%_75% =
= (2 * (height in inches)) - (33.333 * (FEF25%_75%)) + 18.367
