6-min walk-distance norms in adults Arab populations: a literature review

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Monia Daami
Imed Latiri
Sonia Rouatbi
Raoudha Sfaxi
Helmi Ben Saad

Abstract

Introduction. The primary outcome of the 6-min walk-test is the 6-min walk-distance (6MWD). Its interpretation relies upon the comparison of the measured 6MWD with the predicted one from published norms.
Objective. The aim of the present review is to report the 6MWD norms published for healthy adults Arab populations.
Methods. The review includes a literature search, from 1970 to January 5th 2017 using the PubMed search engine. citationsRaw equations lists of retrieved English/French articles were searched for any supplementary citationsRaws. The research includes the combination of the following (or their synonyms) “Medical Subject Headings” or “Title/Abstract” terms: «walking» AND «citationsRaw values» AND «Arabs».
Results. Five studies, conducted in Saudi-Arabia (n=2), Tunisia (n=2) and Algeria (n=1) were included. Norms comprised the following factors: age (Yrs), height (cm), weight (kg), body mass index (BMI, kg/m2), sex (0:women; 1:men) and physical activity level. Five norms were proposed for Tunisian aged 40-79 years [6MWD (m) = 299.8 - 4.34xAge + 3.43xHeight - 1.46xWeight + 62.5xSex] or aged 40-85 years [6MWD (m) = 720.50 + 160.27xSex - 5.14xAge - 2.23xWeight + 2.72xHeight], for Saudi-Arabian aged 16-50 years [6MWD (m) = - 28.5 + 2.81xHeight + 0.79xAge] or aged 18-71 years [6MWD (m) = 342.650 + 74.31xPhysical activity level + 33.88xSex - 4.25xAge] and for Algerian aged 16-40 years [6MWD (m) = 800.05 + 64.71xSex - 10.23xBMI - 1.63xAge + 2.05xWeight]. These norms explained 25% to 77% of the 6MWD variability.
Conclusion. Fewer 6MWD norms exist for adults’ Arab population. Other norms are welcome.

Keywords:

6-min walk distance; Arab; Norms; Reference equation; Reference values; Interpretation

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