Pedometer Step Count Targets during Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease. A Randomized Controlled Trial

Abstract

Rationale: Increasing physical activity is a key therapeutic aim in chronic obstructive pulmonary disease (COPD). Pulmonary rehabilitation (PR) improves exercise capacity, but there is conflicting evidence regarding its ability to improve physical activity levels.

Objectives: To determine whether using pedometers as an adjunct to PR can enhance time spent in at least moderate-intensity physical activity (time expending ≥3 metabolic equivalents [METs]) by people with COPD.

Methods: In this single-blind randomized controlled trial, participants were assigned 1:1 to receive a control intervention (PR comprising 8 wk, two supervised sessions per week) or the trial intervention (PR plus pedometer-directed step targets, reviewed weekly for 8 wk). In the randomization process, we used minimization to balance groups for age, sex, FEV₁ percent predicted, and baseline exercise capacity and physical activity levels. Outcome assessors and PR therapists were blinded to group allocation. The primary analysis was based on the intention-to-treat principle.

Measurements and main results: The primary outcome was change from baseline to 8 weeks in accelerometer-measured daily time expending at least 3 METs. A total of 152 participants (72% male; mean [SD] FEV₁ percent predicted, 50.5% [21.2]; median [first quartile, third quartile] time expending ≥3 METs, 46 [21, 92] min) were enrolled and assigned to the intervention (n = 76) or control (n = 76) arm. There was no significant difference in change in time expending at least 3 METs between the intervention and control groups at 8 weeks (median [first quartile, third quartile] difference, 0.5 [-1.0, 31.0] min; P = 0.87) or at the 6-month follow-up (7.0 [-9, 27] min; P = 0.16).

Conclusions: Pedometer-directed step-count targets during an outpatient PR program did not enhance moderate-intensity physical activity levels in people with COPD. Clinical trial registered with www.clinicaltrials.gov (NCT01719822).

Keywords: chronic obstructive pulmonary disease; physical activity; rehabilitation.

Figure 1.

Consolidated Standards of Reporting Trials diagram of the study. COPD = chronic obstructive pulmonary disease; PR = pulmonary rehabilitation.

Figure 2.

Daily time spent expending at least 3 metabolic equivalents before, after, and 6 months following pulmonary rehabilitation in the control and intervention groups. Data are presented as medians, with error bars representing first quartile and third quartile. METs = metabolic equivalents; PR = pulmonary rehabilitation.

Figure 3.

Progression of daily pedometer step-count targets during PR among participants allocated to the pedometer intervention. The horizontal bars represent the median, the error bars represent the first and third quartiles, and each dot represents a data point.