The association of weather conditions with day-to-day variability in physical activity in patients with COPD

Abstract

BackgroundWhile patients with Chronic Obstructive Pulmonary Disease (COPD) often cite weather conditions as a reason for inactivity, little is known about the relation between physical activity (PA) and weather conditions. The present study investigated the association of day-to-day weather changes on PA in patients with COPD and investigated patient characteristics related to being more or less influenced by weather conditions.MethodsIn this longitudinal analysis, device-based day-by-day step counts were objectively measured in COPD patients for up to 12 months. Daily meteorological data (temperature, precipitation, wind speed, hours of sunlight and daylight) were linked to the daily step count and individual and multivariable relations were investigated using mixed model effects. Individual R2was calculated for every subject to investigate the estimated influence of weather conditions on a patient-level and its relation with patient characteristics.ResultsWe included 50 patients with a mean follow-up time of 282±93 days, totaling 14 117 patient-days. Daily temperature showed a positive linear pattern up until an inflexion point, after which a negative association with increasing temperature was observed (p<0.0001). Sunshine and daylight time had a positive association with PA (p<0.0001). Precipitation and wind speed were negatively associated with PA (p<0.0001). The median per-patient R2for overall weather conditions was 0.08, ranging from 0.00 to 0.42. No strong associations between patient characteristics and per-patient R2were observed.ConclusionWeather conditions are partly associated with PA in patients with COPD, yet the overall explained variance of PA due to weather conditions is rather low and varied strongly between individuals.

Unravelling the complex interplay of factors behind exercise limitations and physical inactivity in COPD

“…Factors such availability of adequate infrastructure, such as lighting, pathways and community areas for exercise [ 60 , 61 ], as well as weather [ 62 ] are all environmental factors that can influence likelihood to engage in exercise and physical activities. Indeed, a recent study confirmed that people with COPD are less active on rainy days and more active on warmer and sunnier days [ 63 ]. Access to safe environments to promote physical activity must become a priority for the healthcare system and society.…”