The Effect of Resistance Training on Markers of Cachexia in Patients with Heart Failure: A Systematic Review and Meta-Analysis

Abstract

Background

Cachexia is a metabolic syndrome characterised by muscle wasting that is highly prevalent in subjects with heart failure (HF) and negatively affects physical function, quality of life, morbidity and mortality. Resistance training has been recently incorporated into cardiac rehabilitation exercise programmes to increase muscle strength in patients with HF. This systematic review and meta-analysis aim to assess the effects of resistance training on markers of cachexia in patients with HF.

Methods

Four electronic databases (MEDLINE, Embase, CENTRAL and CINAHL) were searched to identify randomised controlled trials (RCTs) evaluating the effects of resistance training-only programmes on published criteria for cachexia assessment including muscle strength, body composition (e.g. lean mass/muscle mass) or biochemical markers of cachexia (e.g. inflammatory markers) in patients with HF. Studies were selected based on pre-specified inclusion and exclusion criteria, with a risk of bias assessment carried out. Meta-analyses of muscle strength outcomes were completed using RevMan 5.4.1.

Results

Nine studies were included in this review. Pooled analysis of one repetition-maximum strength test of the lower [SMD 0.67 (95% Cl – 0.12, 1.22) p-value = 0.02] and upper extremities [SMD 1.20 (95% Cl – 0.62, 1.79) p-value <0.0001] showed a significant increase in muscle strength associated with resistance training, which are both important indicators of physical function. Resistance training did not increase muscle strength during rapid movements measured via peak torque at 60, 90 or 180°/s. There were no significant results recorded for changes in body composition and biochemical markers of cachexia. There were inconsistent findings for the effect of resistance training on quality of life. No studies reported findings on measures of anorexia or fatigue.

Conclusions

The findings of this review reveal the potential benefits of resistance training in preserving and enhancing muscle strength in patients with HF who are at risk of cardiac cachexia. Despite inconclusive results on body composition and quality of life, the inclusion of resistance training in cardiac rehabilitation guidelines has the potential to address issues of muscle weakness and frailty. Specific resistance training protocol recommendations to prevent or treat the development of cachexia cannot be made without the publication of more robust RCTs, specifically examining cachectic patients with heart failure with careful assessment of clinical outcomes of markers of cachexia.