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Oxygen Uptake Efficiency Slope in South American Healthy Adults: COMPREHENSIVE REFERENCE VALUES AND INTERNATIONAL
Juliana Goulart Prata Oliveira Milani1, Mauricio Milani, Graziella França Bernardelli Cipriano
1Graduate Programme in Health Sciences and Technologies, University of Brasilia, Brasilia, Brazil (Ms Oliveira Milani and Drs Mauricio Milani, Cipriano, and Cipriano Junior); Fitcordis Exercise Medicine Clinic, Brasilia, Brazil (Ms Oliveira Milani and Dr Mauricio Milani); Rehabilitation Sciences Programme, University of Brasilia, Brasilia, Brazil (Drs Cipriano and Cipriano Junior); Rheumatology Division, School of Medicine, University of São Paulo, São Paulo, Brazil (Dr de Castro); Hasselt University, REVAL/BIOMED, Hasselt, Belgium (Ms Oliveira Milani and Dr Hansen); and Heart Centre Hasselt, Jessa Hospital, Hasselt, Belgium (Dr Hansen).
Purpose:
The purpose of this study is to provide comprehensive reference values for oxygen uptake efficiency slope (OUES) in healthy adults. International heterogeneity was also explored through published databases.
Methods:
A cross-sectional study was conducted with treadmill cardiopulmonary exercise testing (CPX) from a Brazilian healthy adult sample, in which absolute OUES and values normalized by weight and body surface area (BSA) were calculated. Data were stratified by sex and age group. Prediction equations were calculated using age and anthropometric variables. International data were pooled and differences were explored using factorial analysis of variance or the t test, as appropriate. The OUES age-related patterns were calculated using regression analysis.
Results:
A total of 3544 CPX were included (1970 males and 1574 females) and the age ranged from 20-80 yr. Males had higher values than females for OUES, OUES/kg, and OUES/BSA. Lower values were found with aging and the data followed a quadratic regression curve. Reference value tables and predictive equations were provided for absolute and normalized OUES in both sexes. International comparisons of absolute OUES values among Brazilian, European, and Japanese data revealed substantial heterogeneity. The OUES/BSA measure minimized the discrepancies between Brazilian and European data.
Conclusions:
Our study provided comprehensive OUES reference values in a large healthy adult sample from South America with a wide age range and included absolute and normalized values. Differences observed between Brazilian and European data were reduced in the BSA-normalized OUES.
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