Abstract Rationale The six-minute walk test (6MWT) provides a simple, inexpensive and reliable test to evaluate the cardiorespiratory status of patients. Interpretation of 6MWT depends on comparison with reference values of the local population. Presently, there is paucity of reference values from Nigeria thereby limiting applicability. This study aimed to generate reference values for 6MWT among healthy adult population in Ile-Ife, Nigeria. Methods A descriptive cross-sectional study that included 505 healthy adult volunteers recruited through a multistage sampling technique. The purpose and procedure of the study were explained to the participants followed by an interviewer-administered screening physical activity readiness questionnaire and clinical examination to obtain demographic and anthropometric parameters. Six-minute walk test distance was conducted following the American Thoracic Society guidelines. Blood pressure, Heart rate (HR), SpO2 and perceived dyspnoea and rate of exertion were assessed before and after the walk. Measures of exercise intensity, oxygen uptake (Vo2) and metabolic equivalent (METS) were also obtained. Data was analysed using the IBM SPSS version 23.0 software. P value less than 0.05 was taken as statistically significant. Results The age of study participants ranged from 18-88 years with a median age of 37 years; 329 (65.1%) were females. The mean BMI was 24.34 ± 4.84 Kg/m2. Age groups were categorized into young, middle and elderly. Majority (354, 70.1%) of the participants were young while 36 (7.1%) were elderly. The mean of 6MWT distance of participants was 523.97 ± 106.41m. Elderly participants had the lowest mean 6MWD (460.58 ± 125.29 m) compared to the middle and young aged (512.54 ± 101.95 m and 534.14 ± 103.43 m, respectively; p value 0.05). Male gender, young age, height and ΔHR were associated with longer walking distance and the addition of physiologic factors such as ΔHR explained a higher 6MWD variability. The models for each of the statistically significant predictors are stated:Model 1: 6MWD = 750 - 1* Age - 69 * gender (1=male, 2=female) - 3 * BMIModel 2: 6MWD = 730 – 1* Age - 64 * gender (1=male, 2=female) - 3 * BMI + 3*ΔHR Conclusion Six-minute walk test is recommended as a simple, cheap and effective tool for routine assessment of cardiorespiratory status. It is pertinent to determine local reference values and predictive models to enhance its applicability and usefulness. Factors such as age, gender, height, BMI and change in heart rate are important determinants of distance walked. This abstract is funded by: Personal Funds
Chun-Gyang et al. (Fri,) studied this question.