Low leisure-based sitting time and being physically active were associated with reduced odds of death and diabetes in people with chronic obstructive pulmonary disease: a cohort study

Questions In people with chronic obstructive pulmonary disease (COPD), are activity phenotypes (based on physical activity and recreational screen time) associated with mortality and cardiometabolic risk factors? Design Cohort study. Participants People with COPD aged ≥ 40 years and who were current or ex-smokers were identified from the 2003 Scottish Health Survey. Outcome measures Data were collected regarding demographics, anthropometric measurements, medical history, physical activity, sedentary behaviour, health outcomes, and mortality. Analysis Participants were categorised into one of the following activity phenotypes: ‘couch potatoes’ were those who were insufficiently active with high leisure-based sitting time and/or no domestic physical activity; ‘light movers’ were insufficiently active with some domestic physical activity; ‘sedentary exercisers’ were sufficiently active with high leisure-based sitting time; and ‘busy bees’ were sufficiently active with low leisure-based sitting time. ‘Sufficiently active’ was defined as adhering to physical activity (PA) recommendations of ≥ 7.5 metabolic equivalent (MET) hours/week. ‘Low leisure-based sitting time’ was defined as ≤ 200 minutes of recreational screen time/day. Results The 584 participants had a mean age of 64 years (SD 12) and 52% were male. Over 5.5 years (SD 1.3) of follow-up, there were 81 all-cause deaths from 433 COPD participants with available data. Compared to the ‘couch potatoes’, there was a reduced risk of all-cause mortality in the ‘busy bees’ (Hazard Ratio 0.26, 95% CI 0.11 to 0.65) with a trend towards a reduction in mortality risk in the other phenotypes. The odds of diabetes were lower in the ‘busy bees’ compared to the ‘couch potatoes’ (OR 0.14, 95% CI 0.03 to 0.67). Conclusions Adhering to physical activity guidelines and keeping leisure-based sitting time low had a mortality benefit and lowered the odds of diabetes in people with COPD.