Long-term effects of web-based pedometer-mediated intervention on COPD exacerbations

Abstract

Background: Technology-based physical activity (PA) interventions have been shown to improve daily step counts and health-related quality of life, but their effect on long-term clinical outcomes like acute exacerbations (AEs) is unknown in persons with COPD.

Methods: U.S. Veterans with stable COPD were randomized (1:1) to either pedometer alone (control) or pedometer plus a website with feedback, goal-setting, disease education, and a community forum (intervention) for 3 months. AEs were assessed every 3 months over a follow-up period of approximately 15 months. Pedometer-assessed daily step counts, health-related quality-of-life (HRQL), and self-efficacy were assessed at baseline, end-of-intervention at 3 months, and during follow-up approximately 6 and 12 months after enrollment. Zero-inflated Poisson models assessed the effect of the intervention on risk for AEs, compared to controls. Generalized linear mixed-effects models for repeated measures examined between-group and within-group changes in daily step count, HRQL, and self-efficacy.

Results: There were no significant differences in age, FEV1% predicted, baseline daily step count, AEs the year prior to enrollment, or duration of follow-up between the intervention (n = 57) and control (n = 52) groups. The intervention group had a significantly reduced risk of AEs (rate ratio = 0.51, [95%CI 0.31-0.85]), compared to the control group. There were no significant between-group differences in change in average daily step count, HRQL, or self-efficacy at 6 and 12 months after enrollment.

Conclusions: A 3-month internet-mediated, pedometer-based PA intervention was associated with reduced risk for AEs of COPD over 12-15 months of follow-up. ClinicalTrials.gov identifier: NCT01772082.

Keywords: COPD; Exacerbations; Physical activity; Randomized controlled trial.

Conflict of interest statement

Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Moy reports receiving an honorarium for consulting from AstraZeneca, outside the submitted work. The remaining authors have no relevant conflicts to disclose.

Published by Elsevier Ltd.

Figures

Fig. 1.

Overview of study and follow-up timeline. Study consisted of in-person visits (red hatched arrow) and telephone interviews (blue solid arrows) over 15 months. Semi-structured questionnaires at all follow-up time points assessed occurrence of self-reported AEs over the preceding 3 months. Daily step count was assessed with the Omron pedometer at V1, V2, FU1, and FU3. AEs = acute exacerbations; SGRQ = St. George’s Respiratory Questionnaire; Ex- SRES = Exercise Self-Regulatory Efficacy Scale. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2.

Change in average daily step count from baseline by randomization group. Change in average daily step count from baseline (V1) from adjusted regression model (least square means values). There were no significant between-group differences in change average daily step count from baseline. Blue and red stars denote a significant (p < 0.05) within group change from baseline in the pedometer-only and pedometer plus website groups, respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 3.

Change in Saint George’s Respiratory Questionnaire (SGRQ) total score from baseline by randomization group. Change in St. George’ s Respiratory Questionnaire Total Score (SGRQ-TS) from baseline (V1) from adjusted regression model (least square means values). There were no significant between-group differences in change in SGRQ-TS from baseline. The blue star denotes a significant (p < 0.05) within group change in SGRQ-TS score from baseline in the pedometer-only group at FU1. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 4.

Change in Exercise Self-Regulatory Efficacy Scale (Ex-SRES) from baseline by randomization group. Change in Exercise Self-Regulatory Exercise Score (Ex-SRES) from baseline (V1) from adjusted regression model (least square means values). There were no significant between-group differences in change Ex-SRES from baseline. Blue and red stars denote a significant (p < 0.05) within group change from baseline in the pedometer-only and pedometer plus website groups, respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)