Applicability of commonly used Caucasian and Multi

‐

ethnic reference prediction equations for spirometry interpretation in Tunisian adult’s population

Ben Saad H, Maatoug C, Thabet H, Amimi S, Rouatbi S, Hadj Mabrouk K Groupement du Médecine du Travail du Gouvernorat de Sousse

RESULTS INTRODUCTION

The applicability of Caucasian prediction equations described by the European Community for Coal and Steel (ECCS 1983 )

[1]

and currently used in Tunisia, or the recent Multi ‐ ethnic reference values derived by the Global Lungs Initiative (GLI 2012 )

[2]

in interpreting spirometry data in Tunisian subjects has not been studied.

AIMS

To evaluate if Caucasian, Multi-ethnic and Tunisian prediction equations can be used interchangeably while interpreting routine spirometric data.

POPULATION AND METHODS

Population:

♂/7 ♀) 38 Tunisian adults: 19 healthy lifelong non-smokers (8 ♂/11 ♀) and 19 smokers (12

Spirometry measurements:

done according recent international guidelines (ATS/ERS 2005 ).

Applied spirometric reference equations:

ECCS 1983

[1]

, GLI 2012

[2]

.

Tunisian reference equations [Tunisia 1995 ]

[3] Measured/calculated spirometric data:

predicted values and lower limit of normal (LLN), according each reference equations, for the following spirometric parameters: 1 st forced expiratory volume (FEV 1 ), forced vital capacity (FVC), FEV 1 /FVC ratio, maximum mid expiratory flow (MMEF) and expiratory flow when 75% of FVC has been exhaled (FEF 75% ).

,

Applied definition:

large airway obstructive ventilatory defect (AOVD): FEV 1 /FVC < LLN. Small AOVD: FVC > LLN and MMEF < LLN. Tendency through a restrictive ventilatory defect (TRVD): FEV 1 and FVC < LLN and FEV 1 /FVC> LLN. The spirometric profile of each subject was determined according the three reference equations [

1-3]

.

Statistical analysis:

A non parametric test was applied to compare the measured/calculated spirometric data expressed as a percentage of predicted values (%pred) and the LLN calculated from the 3 reference equations [

1-3]

.

CONCLUSION

The use of Caucasian or Multhi-ethnic prediction equations resulted in misinterpretation of spirometry data in a significant proportion of subjects.

REFERENCES 1.

Quanjer PhH (ed.). Standardized lung function testing. Bull Europ Physiopathol Respir 1983; 19 (supll 5): 1 95. 2. Quanjer PH et al. Multi-ethnic reference values for spirometry for the 3-95 year age range. Report of the Global Lungs Initiative, ERS tTask force to establish improved lung function reference values.

ERJ Express

.

Published on June 27, 2012 as doi: 10.1183/09031936.00080312.

values in a Tunisian population. Tunis Med. 1995;73:125-31.

3.

. Tabka Z et al. Spirometric reference