Verification of the reliability of theoretical spirometric values of the Global Lung Function Initiative in elite athletes

BACKGROUND: The interpretation of spirometric data needs the comparison between the measurements observed and the predicted values of subjects of the same sex, age, height, and ethnicity. The reliability of GLI-2012 predicted values, recently published for the general population, has been investigated in athletes. METHODS: A total of 1490 spirometries were carried out for healthy, Caucasian, high-level athletes of both sexes (909 males, 581 females) practicing heterogeneous sport activities. A comparison was made between measured FVC and FEV1 and predicted values obtained from GLI-2012 equations, depending on age and height. RESULTS: For both sexes, the average values measured of FVC and FEV1 were significantly higher than the GLI-2012 values. Depending on age there is a developmental phase which is different in the two sexes and reaching the maximum between 24-26 years of age. This phase is followed by a slight decrease in later years with measured values higher than the predicted ones in relation to the age examined. Depending on the height of the two sexes, an exponential increase is observed for the measured and GLI-2012 values, with the firsts higher than the predicted ones and with difference that decreases in relation to the height increasing, until is cancelled. CONCLUSIONS: This study has shown that in high-level athletes, pulmonary volumes are higher than GLI-2012 values for the general population, both in reference to the age considered (12-35 years) and height. Furthermore, this difference gradually decreases. The difference between the measured values and the GLI-2012 values weakens the reliability of the latter in the respiratory evaluation of athletes.