Abstract
Rationale: Lung function testing interpretation is based on predicted equations derived from healthy people sample, but this practice can lead to lack of accuracy when dealing with extremes of age and height. More recently, a global equation was proposed, challenging the paradigm of specific regional derived equations.
Objective: To verify the accuracy of different predicted equations for lung function to a healthy elderly sample.
Methods: Lung function tests was performed in 83 healthy non-smoker elderly (65 to 93 years-old, 52 females). Results were compared with predicted values obtained from equations from the same geographic area (Brazil) and from global and european equations (GLI/ECCS) using paired t-test.
Results: Elderly women data showed good accuracy only with Brazilian equations for FVC and FEV1 and men results fit well only for FEV1 (GLI), TLC (Brazilian) .
Observed (mean ± SD) | Brazilian | GLI/ECCS | |
FVC (L) | 2,5 ± 0,4 | 2,48 (p=0,22) | 2,35 (p<0,001) |
FEV1 (L) | 1,9 ± 0,34 | 1,92 (p=0,43) | 1,82 (p=0,004) |
FEV1/FVC | 0,77 ± 0,05 | 0,78 (p=0,021) | 0,78 (p=0,024) |
TLC (L) | 4,9 ± 0,87 | 4,45 (p<0,001) | 4,32 (p<0,001) |
DLCO | 18,2± 3,1 | 33,4 (p<0,001) | 20,1 (p<001) |
Observed (mean ± SD) | Brazilian | GLI/ECCS | |
FVC (L) | 3,70 ± 0,71 | 3,9 (p=0,03) | 3,52 (p=0,03) |
FEV1 (L) | 2,71 ± 0,51 | 2,97 (p<0,001) | 2,77 (p=0,19) |
FEV1/FVC | 0,74 ± 0,056 | 0,76 (p<0,005) | 0,76 (p=0,007) |
TLC (L) | 6,38 ± 0,94 | 6,46 (p=0,31) | 5,53 (p<0,001) |
DLCO | 24,8 ± 5,5 | 30,6 (p<0,001) | 26,4 (p=0,037) |
Conclusions: Data suggest a lack of accuracy of available equations for elderly people. The clinical relevance of observed differences, their influence on testing interpretation and the role of specific-age equations have to be better clarified.
- Copyright ©the authors 2016