PURPOSE: The Six Minute Walk Test is an important tool in screening, management and prognostication of Pulmonary and Cardiovascular diseases. However there is no available data on the normal six minute walk distance (6MWD)in the Asian Indian population. Our purpose was to define the normal 6MWD and assign reference equations in the Indian population.
METHODS: A cross-sectional study in healthy volunteers of age more than forty were selected from the hospital staff and patient's attendants at St. Johns Hospital. Only those subjects with a sedentary lifestyle were screened by clinical methods, ECG and spirometry. The subjects then underwent the Six minute walk testing in accordance to the ATS guidelines. The 6MWDs were recorded. Two-sample t test was used to compare 6MWD in the male and female populations and that with the western population. Multiple regression was used to determine the reference equations.
RESULTS: 102 subjects were enrolled, of which eight were excluded. The mean 6MWD in the males were 604 mts. (p<0.001; 95% CI=590-618) and in females were 544 mts. (p<0.001; 95% CI=532-557). Compared to the western population the mean 6MWD were different in both males (29 mts; p=0.009) and females (31 mts; p=0.003). The reference equations in males - 200.1 + [3.4 X Height (cms)] –[1.9 X Age (years)] –[1.1 X weight (kgs.)] (Coefficient of determination R2=46.7; p<0.001) and in females –256.8 + [2.4 X Height (cms)] –[1.5 X Age (years)] –[0.3 X weight (kgs.)] (Coefficient of determination R2=33.0; p<0.001).
CONCLUSION: The mean 6MWD in indians is significantly different from the western population and the same between the male and female population, thus justifiying the need to determine the mean 6MWD in these populations and the equations to predict the same.
CLINICAL IMPLICATIONS: The mean value for the 6MWD and reference equations can be used to guide the management of Pulmonary and Cardiovascular diseases in the Indian population.
DISCLOSURE: Avinash Srikanth, None.