Les équations de référence pléthysmographiques établies chez les adultes natifs de l’Est Algérien sont inapplicables pour ceux natifs du Nord Algérien

Abstract

The validity of the published plethysmographic reference equations specific to adults living in Eastern Algeria (RE-EA) in the interpretation of spirometric results in adult natives of Northern Algeria has not been assessed. To test the application of the RE-EA (Constantine, mean altitude=694m) to a population of healthy adults living in Algiers (mean altitude=153m). The plethysmographic parameters of 453 healthy adults living in Algiers (234 women; age: 45±15 years, height: 1.66±0.10m, weight: 73±14kg) were determined and were compared with those predicted from the RE-EA. In addition, the percentages of adults with an obstructive ventilatory defect (OVD), a restrictive ventilatory defect (RVD) and/or lung hyperinflation were noted. The RE-EA are considered inapplicable to healthy adults living in Algiers if, firstly, the differences between the determined and predicted plethysmographic parameters are statistically significant and, secondly, more than 5% of healthy adults have OVD and/or RVD and/or lung hyperinflation. The RE-EA significantly overestimated the following parameters: FEV1 by 0.27±0.39L, MMEF by 0.52±0.75L/s, FEF25% by 0.75±0.56L/s, FEF50% by 0.85±1.02L/s, FEF75% by 0.28±1.25L/s, VC by 0.21±0.50L, TLC by 0.31±0.62L, ERV by 0.06±0.48L, IC by 0.27±0.48L, FEV1/VC by 0.03±0.05, and FEV1/FVC by 0.03±0.05. They significantly underestimated the RV/TLC by 0.01±0.05. Moreover, 14.35 %, 8.83 % and 5.74 % of healthy adults had OVD, RVD and lung hyperinflation, respectively. The RE-EA are not applicable in adult natives of Northern Algeria.