Predictors of exercise capacity following exercise-based rehabilitation in patients with coronary heart disease and heart failure: A meta-regression analysis.
BACKGROUND
The aim of this study was to undertake a comprehensive assessment of the patient, intervention and trial-level factors that may predict exercise capacity following exercise-based rehabilitation in patients with coronary heart disease and heart failure.


METHODS
Meta-analysis and meta-regression analysis.


METHODS
Randomized controlled trials of exercise-based rehabilitation were identified from three published systematic reviews. Exercise capacity was pooled across trials using random effects meta-analysis, and meta-regression used to examine the association between exercise capacity and a range of patient (e.g. age), intervention (e.g. exercise frequency) and trial (e.g. risk of bias) factors.


RESULTS
55 trials (61 exercise-control comparisons, 7553 patients) were included. Following exercise-based rehabilitation compared to control, overall exercise capacity was on average 0.95 (95% CI: 0.76-1.41) standard deviation units higher, and in trials reporting maximum oxygen uptake (VO2max) was 3.3 ml/kg.min(-1) (95% CI: 2.6-4.0) higher. There was evidence of a high level of statistical heterogeneity across trials (I(2) statistic > 50%). In multivariable meta-regression analysis, only exercise intervention intensity was found to be significantly associated with VO2max (P = 0.04); those trials with the highest average exercise intensity had the largest mean post-rehabilitation VO2max compared to control.


CONCLUSIONS
We found considerable heterogeneity across randomized controlled trials in the magnitude of improvement in exercise capacity following exercise-based rehabilitation compared to control among patients with coronary heart disease or heart failure. Whilst higher exercise intensities were associated with a greater level of post-rehabilitation exercise capacity, there was no strong evidence to support other intervention, patient or trial factors to be predictive.
Department of Cardiac Surgery, Ibrahim Cardiac Hospital & Research Institute, Bangladesh National Institute of Public Health, University of Southern Denmark, Denmark.
Jamal
J
Uddin
National Institute of Public Health, University of Southern Denmark, Denmark.
Ann-Dorthe
AD
Zwisler
Department of Cardiology, Vejle Hospital, Vejle, Denmark.
Christian
C
Lewinter
Non-communicable Disease Unit, World Health Organization (WHO), Country office for Bangladesh, Dhaka, Bangladesh.
Mohammad
M
Moniruzzaman
Department of Physiotherapy and Occupational Therapy, Holbaek Hospital, Denmark.
Ken
K
Lund
The Heart Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark CopenRehab, Section of Social Medicine, Department of Public Health, University of Copenhagen, Denmark Bachelor's Degree Programme in Physiotherapy, Dept. of Rehabilitation and Nutrition, Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark.
Lars H
LH
Tang
National Institute of Public Health, University of Southern Denmark, Denmark Institute of Health Research, University of Exeter Medical School, Exeter, UK r.taylor@exeter.ac.uk.
Rod S
RS
Taylor
D003324:Coronary Artery Disease / Q000503:physiopathology / Q000534:rehabilitation*; D005081:Exercise Therapy / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D006333:Heart Failure / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D011379:Prognosis; D011788:Quality of Life
Exercise training; cardiac rehabilitation; coronary heart disease; exercise capacity; heart failure; meta-analysis