Background  A recent study established threshold values for 6 minute walk distance (6MWD) and steps/day for predicting mortality (i.e. 404 m and 4125 steps/day for men; 394 m and 4005 steps/day for women) in Dutch COPD patients. The 6-year mortality risk was significantly lower in patients with a preserved 6MWD, regardless of number of steps/day (Vaes et al. Chest 2022). We aimed to corroborate these findings in a Swiss cohort of COPD patients.

Methods Data were collected in 261 COPD patients (65% male, age: 63±8 years, FEV1: 48±22% pred.). All-cause mortality was assessed for a median period of 67 (44-83) months. ROC curves were used to determine thresholds for 6MWD and steps/day to predict 6-year mortality.

Results Best thresholds were 401 m and 4028 steps/day for men and 394 m and 3457 steps/day for women. Using these cutoffs, patients were divided into the ?can do, do do? quadrants: 1)"can?t do, don?t do? (n=75, 29%); 2)"can do, don?t do? (n=38, 15%); 3)?can?t do, do do? (n=42, 16%); and 4)?can do, do do? (n=106, 41%). After controlling for sex, age, FEV1, MRC and BMI, patients in the ?can do, do do? quadrant had a significantly lower all-cause mortality compared to the ?can?t do, don?t do? and "can't do, do do" quadrants; no differences were found with the "can do, don't do" quadrant.


Conclusion Data confirm earlier thresholds for mortality in COPD and that 6-year mortality risk is lowest in patients with a preserved 6MWD, regardless of steps/day.