Document Type



Pulmonary and Critical Care


Objective: To determine the six-minute walking distance (6MWD) for healthy Pakistanis, identify factors affecting 6MWD, compare published equations with the local data and derive an equation. Study Design: Cross-sectional study. Place and Duration of Study: Two medical institutes of Karachi, from January to May 2011. Methodology: Subjects between 15 and 65 years were prospectively enrolled after screening. A standardized 6MWT was administered. SpO2, HR, BP and dyspnoea scores were determined pre- and post-test. Results: Two hundred and eleven (71%) men and 85 (29%) women participated. Mean 6MWD was 469.88 ± 101.24 m: men walked 502.35 ± 92.21 m and women walked 389.28 ± 74.29 m. On univariate analysis, gender, height, weight and age showed a significant relationship with the 6MWD. Gender and age were identified as independent factors in multiple regression analysis, and together explained 33% of the variance. The gender-specific prediction equations were: 6MWD (m) for men = 164.08 + (78.06*1) - (1.90*age in years) + (1.95*height in cms) 6MWD (m) for women = 164.08 - (1.90*age in years) + (1.95*height in cms). Conclusion: 6MWDs among the volunteer subjects were shorter than predicted by reference equations in literature. Height, gender and weight combined explained 33% of the variance. The moderate over-estimation of the 6MWD in Pakistani subject. The proposed equation gives predicted (mean) 6MWDs for adult Pakistani naïve to the test when employing standardized protocol.


Journal of the College of Physicians and Surgeons Pakistan