Physical Activity and Capacity in Patients With COPD in Urban Environments

The physical activity and capacity of patients with chronic obstructive pulmonary disease (COPD) living in highly populated areas is related to population density, nitrogen dioxide (NO₂) exposure, pedestrian street length, and terrain slope, according to analysis findings published in Environmental Research.

Understanding key factors beyond COPD itself that influence physical activity in COPD patients is critical for determining and supporting physical activity interventions, yet research on the influence of environmental factors is limited. Researchers in Spain therefore sought to assess the associations between physical activity in individuals with mild to severe COPD and such factors as population density, pedestrian street length, slope of terrain, and exposure to NO₂, road traffic noise, and particulate matter.

The investigators initiated a cross-sectional analysis of data from the multi-center Urban Training study (ClinicalTrials.gov Identifier: NCT01897298), conducted at 33 primary care centers and 5 tertiary hospitals in Spain between October 2013 and February 2015. All of the 407 patients (69±9 years of age; 15% women) had been diagnosed with COPD. Each study participant walked 7524 (±4045) steps per day.

Researchers found that higher population density was linked with fewer steps (-507 steps; 95% CI, -1135 to 121), more sedentary time (+0.2; 95% CI, 0.0-0.4 hours/day), and poorer exercise capacity (-13; 95% CI, -25.0 to 0.0 meters/IQR). Pedestrian street length was linked with more steps (156 steps; 95% CI, 9.0-304), and less sedentary time (-0.1; 95% CI, -0.1 to 0.0 h/day per IQR). Steeper slope was linked with greater exercise capacity (15; 95% CI, 3-27 m/IQR).

Neither particulate matter nor road traffic noise were associated with physical activity or exercise capacity, the researchers found. However, greater NO₂ levels were linked with greater sedentary time and greater difficulty in physical activity.

Analysis limitations include a lack of accounting for many environmental factors and pollutants; the use of annual averages to estimate real exposure to air pollutants or street traffic noise; causality and directionality issues related to the study’s cross-sectional design; the preponderance of men; and self-selection bias.

Researchers concluded their analysis showed that “Population density, pedestrian street length, slope, and NO₂ exposure relate to physical activity and capacity of COPD patients living in highly populated areas.” They found no link between exercise capacity and physical activity and road traffic noise or particulate matter. They went on to add that their findings, “support the consideration of neighborhood environmental factors during COPD management and the attention to patients with chronic diseases when developing urban and transport planning policies.”  

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Koreny M, Arbillaga-Etxarri A, de Basea MB, et al. Urban environment and physical activity and capacity in patients with chronic obstructive pulmonary disease. Environ Res. Published online July 21, 2022. doi:10.1016/j.envres.2022.113956