Changes in cardiorespiratory fitness in cardiac rehabilitation patients: a meta-analysis

Int J Cardiol. 2013 Aug 10;167(3):894-902. doi: 10.1016/j.ijcard.2011.11.068. Epub 2011 Dec 27.


Background/objectives: Improving patients' cardiorespiratory fitness is an important therapeutic outcome in cardiac rehabilitation. The ability of cardiac rehabilitation to reduce mortality and morbidity has been evidenced through several meta-analyses. Whether cardiac rehabilitation can increase cardiorespiratory fitness and which factors may influence such gains are less well quantified.

Methods: We performed detailed literature searches of electronic databases and manually searched papers concerning changes in cardiorespiratory fitness in cardiac rehabilitation patients. We performed random-effects meta-analysis of mean improvements in cardiorespiratory fitness and subgroup analyses to determine potential sources of heterogeneity.

Results: Data from 31 studies produced 48 groups (n=3827) with a mean improvement of 1.55 (95% CI 1.21-1.89) METs, (p<0.001); equivalent to standardised effect size of ES=0.97 (95% CI 0.80-1.13). As this value was highly heterogeneous (Q=852, p<0.001) we performed subgroup analyses on the effect size data. Gains in fitness were highest in patients receiving >36 exercise sessions in studies where fitness was assessed using the Naughton Protocol. Patient characteristics associated with the highest fitness gains were age (being young) and sex (being male training in a male-only exercise group). Changes in fitness were unrelated to programme type (comprehensive or exercise-only), duration or study design. There was no association with patient's baseline fitness levels.

Conclusion: This is the first meta-analysis of changes in cardiovascular fitness in cardiac rehabilitation patients and shows clinically significant improvements in a large sample of patients from a variety of rehabilitation programmes. This analysis helps describe the characteristics of cardiac rehabilitation programmes which can increase patients' cardiorespiratory fitness.

Keywords: Cardiovascular disease; Exercise; Meta-analysis; Rehabilitation.

Publication types

  • Meta-Analysis

MeSH terms

  • Cardiac Rehabilitation*
  • Cardiovascular Diseases / diagnosis
  • Cardiovascular Diseases / physiopathology*
  • Cohort Studies
  • Exercise Therapy / methods*
  • Exercise Therapy / trends
  • Humans
  • Physical Fitness / physiology*
  • Randomized Controlled Trials as Topic / trends
  • Treatment Outcome