Time for new reference values for ventilatory lung function

The anthropometrical data of our aging population has significantly changed within the last five decades. Therefore the question arises whether or not the commonly used reference values of the European Community (ECCS) for lung function, may still be accepted today. Measured values for elderly are classified by extrapolation beyond the range of reference equations.

Lung function was examined by pneumotachography for recording static lung volumes and flow-volume-curves in 257 asymptomatic non smoking males, aged 20-90 years. Results were compared to the reference values of ECCS, SAPALDIA, LuftiBus, and NHANES.

For analysis age and height dependence of investigated respiratory parameters (VC, FVC, FEV(1), FEV(1) %FVC, PEF, MEF(75,50,25)) can for simplicity be described by linear functions (y = a . height(H)-b . age (A)+c). The forced expiratory volume in one second, FEV(1), was calculated by FEV(1) = 0.0432 . H-0.0347 . A -2.114; where H - height, A - age; r = 0.78. Mean FEV(1) for younger subjects was found to be 106.1 +/- 11.2% of the ECCS reference values and 97.8 +/- 11.7% in older subjects. For all parameters investigated linear regressions on age were steeper than described by the ECCS reference values. The regression of lung function to height largely follows the ECCS prescriptions.

Bochum lung function values of healthy subjects showed a steeper age descent compared to the reference values of the ECCS. The alternatively discussed reference values of the SAPALDIA-, NHANES- or LuftiBus-Study are higher, but do not cover all necessary parameters and/or the age range. A multi centre study for contemporary reference values is recommended.