Reference values for the six-minute walk test in Nigerian adolescents aged 10 to 18 years

Abstract

Objective: To determine baseline six-minute walk distance in Nigerian adolescents and establish its relationship with age, gender and anthropometric parameters. Methods:One hundred and eighty healthy adolescents (10 -18 years) were recruited from three schools. Six-minute walk test was conducted as described by the American Thoracic Society. Demographic and anthropometric characteristics were related to achieve six-minute walk distance. A mathematical formula for predicting six-minute walk distance was generated. Results:The mean ± SD six-minute walk distance was 590.1 ± 72.02 m and was significantly longer in males (p= 0.001) among adolescents aged 10-16 years. Age was the only characteristic significantly associated with six-minute walk distance following multiple linear regression analyses. The formulae, [six-minute walk distance = 317.3 + 21.5 x age (years) in males and 117 + 33.0 x age (years) in females] closely approximated to measured six-minute walk distance. Conclusion:This study has derived reference values for 6-minute walk test in adolescents; the use of these reference values should consider age and gender variations.

Reference values and equations for the 6‐minute walk distance of Nigerian children aged 6–11 years: A cross‐sectional study

“…A mean of 504 m in our study falls within the global range of 6MWD among healthy children 9–11 . Compared with mean 6MWD of Nigerian adolescents previously reported by Abdulkadir et al, 12 10–11‐year‐old boys and girls in our study walked 544 and 530 m, respectively, while 10–12‐year‐old boys and girls walked 545 and 491 m, respectively, in the former study, suggesting similar performances at least in boys.…”

“…Also, none of previously published equations satisfactorily predicted our sample's 6MWD. Our data add to published 6MWT standards for Nigerian adolescents 12 and adults, 6,13 thus completing Nigerian references spanning pre‐adolescence to adulthood, while also filling an acknowledged paucity of 6MWD data from sub‐Saharan Africa 7,10 …”

Development of reference equations for the six-minute walk distance of school-aged Nigerian children

“…(31) A mean of 504 m in our study falls within the range of published studies, including systematic reviews by Mylius et al (14) and Cacau et al, (16) of mean 6MWD from healthy children. Compared with previous study by Abdulkadir et al (21) amongst Nigerian adolescents, 10-11-year-old boys and girls in our study walked 544 and 530 m, respectively, while 10-12-year old boys and girls walked 545 m and 491 m, respectively, suggesting similar performances at least in boys. Our 6MWD also compares with 518 m walked by 7-11 year-old North American children.…”

“…Also, none of previously published reference equations satisfactorily predicted our cohort's 6MWD. Our data adds to existing published ones for Nigerian adolescents (21) and adults, (8,22) thus completing Nigerian references spanning school-age to adulthood, while also filling an acknowledged paucity of 6MWT data from sub-Saharan Africa. (9,15) The 6MWT is a valid and reliable measure of functional exercise capacity widely used in adults and children with disorders like asthma, congenital heart diseases, sickle cell disorders and others.…”

“…(14)(15)(16)(18)(19)(20) The American Thoracic Society (ATS) and European Respiratory Society (ERS) thus recommend development of reference standards from local populations. (7) In Nigeria, although reference standards are available for adolescents (21) and adults (8,22), none is available in pre-adolescents school-age children. This cross-sectional study thus determined the mean 6MWD of healthy 6 to 11-year-old Nigerian children, its predictors (including chest circumference, which has not been previously evaluated) and reference equations; we also assessed the predictive performance of previously published equations.…”