Although individual studies have reported on the number of steps/day taken by individuals with chronic obstructive pulmonary disease (COPD), this evidence has not been systematically reviewed or synthesized.
MEDLINE and PsycINFO were searched for studies reporting objectively-measured steps/day and percent predicted forced expiratory volume in 1 second (FEV1%) in patients with COPD. Meta-analyses were used to estimate steps/day across studies, while metaregression was used to estimate between-study variance based on clinical and demographic factors (year and location of study, activity monitor brand, number of days wearing the monitor, whether participants were about to enter pulmonary rehabilitation, 6-minute walk distance (6MWD), FEV1%, age, and sex).
38 studies including 2621 participants met inclusion criteria. The pooled mean estimate was 4579 steps/day (95% CI:4310 to 5208) for individuals with COPD. Only 6MWD, FEV1% and whether patients were about to undergo pulmonary rehabilitation explained a significant portion of the variance (P < 0.1) in univariate meta-regression. In a multivariate model including the above risk factors, only FEV1% was associated with steps/day after adjustment for other covariates.
These results indicate that patients with COPD achieve extremely low levels of physical activity as assessed by steps/day, and that severity of airflow obstruction is associated with activity level.
Saunders is with the Dept of Applied Human Sciences, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada. Campbell is with the Cardiovascular Research Unit, Nova Scotia Health Authority, Halifax, NS, Canada. Jason, Hernandez, Thompson, and Blanchard are with the Dept of Medicine; Dechman is with the School of Physiotherapy; Dalhousie University, Halifax, NS, Canada.