title: 6-minute walk distance in healthy North Africans older than 40 years: influence of parity.
abstract: The need for a 6-min walk distance (6-MWD) reference equation for healthy North African adults older than 40 years was assessed in a prospective cross-sectional study. Anthropometric data and 6-MWD were measured in 229 healthy Tunisian adults (125 women) over 40 years old. Two subgroups of 38 women were identified according to the parity (low<or=5; high>or=6). The published reference equations did not reliably predict measured 6-MWD. The 6-MWD was significantly correlated with gender, age, weight and height (p<0.001). The combination of these parameters explained 77% of the 6-MWD variability in the equation: 6-MWD (m)=-160.27 x gender (0: men; 1: women) - 5.14 x age (yr) - 2.23 x weight (kg)+2.72 x height (cm)+720.50. Parity accelerated the 6-MWD decline (r=-0.39, p<0.05) and women distinguished only by parity (<or=5 vs. >or=6) showed different 6-MWD (589+/-60 m vs. 555+/-57 m, p<0.05). In an additional group of 30 adults prospectively studied to validate the equation, the agreement between the measured and equation-predicted 6-MWD was satisfactory. In conclusion, this reliable 6-MWD reference equation enriches the World Bank and provides an important element of interpretation for women with high parity.
authors.affiliation: Service de Physiologie et des Explorations Fonctionnelles, EPS Farhat Hached, Sousse, Tunisia.
authors.forename: Helmi
authors.initials: H
authors.lastname: Ben Saad
authors.forename: Christian
authors.initials: C
authors.lastname: Prefaut
authors.forename: Zouhair
authors.initials: Z
authors.lastname: Tabka
authors.forename: Abdelaziz Hadj
authors.initials: AH
authors.lastname: Mtir
authors.forename: Mohamed
authors.initials: M
authors.lastname: Chemit
authors.forename: Rym
authors.initials: R
authors.lastname: Hassaoune
authors.forename: Tarek
authors.initials: T
authors.lastname: Ben Abid
authors.forename: Khelifa
authors.initials: K
authors.lastname: Zara
authors.forename: Grégoire
authors.initials: G
authors.lastname: Mercier
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Zbidi
authors.forename: Maurice
authors.initials: M
authors.lastname: Hayot
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D044383:Black People; D001827:Body Height; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D003906:Developing Countries; D004562:Electrocardiography; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010298:Parity; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D012737:Sex Factors; D013147:Spirometry; D014416:Tunisia; D016138:Walking