1. Change in physical activity level following COPD exacerbation
Paul Andrzejowski 1, Neil Greening 2, Matthew Richardson 2 , Theresa Harvey-Dunstan 2, Linzy Houchen-Wolloff 2 , Emma Chaplin 2 ,
Fayyaz Hussain 1, Michael Steiner 2, and Sally Singh 2.
1 Respiratory Medicine, Kettering General Hospital, Kettering, Northamptonshire, United Kingdom, NN16 8UZ
2 Biomedical Research Unit, Glenfield Hospital, University Hospitals of Leicester, Leicester, Leicestershire, United Kingdom, LE3 9PQ.
Introduction: There appears to be a link between improving physical activity (PA ) after hospital discharge for acute exacerbation (AE) of COPD and reduction in subsequent readmission rate (1-4). We have previously reported the main outcomes from the REACH trial (5), which offered an early in-patient exercise based intervention for patients admitted with an exacerbation of their chronic respiratory disease. The patients were supported upon discharge with a self management programme. We anticipated that the intervention would improve physical activity levels and this in turn may be associated with a reduced readmission rate. This data describes a sub analysis of the physical activity monitor data.
Methods: Of 389 patients in main study, data from 94 patients - early rehabilitation (PR) vs. control - was collected: at exacerbation (baseline), 6 weeks post exacerbation, 3 months post exacerbation. The groups were broadly similar. See characteristics in table 1.
Eligibility criteria included a minimum of 12 waking hours captured, for at least two days of activity monitor data at each time-point.
Sensewear PA monitors (BodyMedia- figure 1) were used to record the following information on PA: Total PA time, total energy expenditure (TEE), steps, and metabolic equivalent of task levels (6) (METs): sedentary (1.5-2), very light ( ), light (2.5-3) and moderate (3-6).
Analysis: A non-parametric Kruskal-Wallis test was used to assess the impact of confounding variables. A repeated measures model was fitted to describe PA over the 3 time points. Logistic and generalised linear regression models were fitted to predict risk of readmission within 12 months following AECOPD.
Figure 1
Results: There were no significant differences in any of the variables examined between the intervention group compared to control except for light activity at 0-6 weeks (p=0.031). Baseline levels of activity were very low in both groups and activity levels increased over time. See figure 2.
We therefore collapsed the groups and explored the data for differences in PA and readmission. We examined the collapsed data using the variables described above. We found that a greater increase in TEE over time was associated with a reduction in readmissions (p=0.018: univariate model, p=0.024: multivariate model). See figure 3.
A change in sedentary behaviour was associated with a reduction in readmissions. Those patients who were able to reduce their sedentary time had a reduced rate of readmission (p=0.029: univariate model, p=0.048: multivariate model). See figure 4.
Variables
Sub Analysis
Main Study
Not Readmitted (n=41)
Readmitted (n=53)
Usual Care (n=193)
Intervention (n=196)
Men (%)
17 (41.5 %)
25 (47.2 %)
85 (44 %)
88 (45 %)
Mean (SD) age (years)
70.84 (5.28)
67.60 (8.34)
71.2(10.0)
71.1(9.4)
Mean (SD) FEV1 (L)
1.41 (0.77)
1.16 (0.60)
1.28 (0.64)
1.12 (0.61)
Table 1
Steps over time between intervention
and usual care groups
Change from baseline in
Total Energy Expenditure
Change from baseline in
Sedentary behaviour
Mean ± SEM
Mean ± SEM
Mean ± SEM * *
(Minutes)
* P ≤ 0.05
(Kcal)
* P ≤ 0.05
Figure 3
Figure 4
Figure 2
Conclusions: Overall, early rehabilitation did not result in significant differences to the levels of PA following AECOPD; the natural recovery of patients occurred regardless of intervention group.
The 'collapsed' data suggests that rate of change in TEE and sedentary behaviour in the first six weeks following discharge after AECOPD might be important in predicting the risk of readmission at one year, which could have implications for design of future rehabilitation programmes.
References
Chawla H, et al. Physical activity as a predictor of thirty-day hospital readmission after a discharge for a clinical exacerbation of chronic obstructive pulmonary disease. Ann Am Thorac Soc. 2014;11(8): ,
Pitta F, Troosters T, Probst VS, Spruit MA, Decramer M, Gosselink R. Physical activity and hospitalization for exacerbation of COPD. Chest. 2006;129(3):
Garcia-Aymerich J, Lange P, Benet M, Schnohr P, Antó JM. Regular physical activity reduces hospital admission and mortality in chronic obstructive pulmonary disease: a population based cohort study. Thorax. 2006;61(9): ,
Nguyen HQ, Chu L, Amy Liu IL, et al. Associations between physical activity and 30-day readmission risk in chronic obstructive pulmonary disease. Ann Am Thorac Soc. 2014;11(5):
5) Greening NJ, Williams JE, Hussain SF, et al. An early rehabilitation intervention to enhance recovery during hospital admission for an exacerbation of chronic respiratory disease: randomised controlled trial. BMJ. 2014;349:g4315
6) Ainsworth BE, Haskell WL, Whitt MC, et al. Compendium of physical activities: an update of activity codes and MET intensities. Med Sci Sports Exerc. 2000;32(9 Suppl):S