Cytokines and neurohormones relating to body composition alterations in the wasting syndrome of chronic heart failure

Background Chronic heart failure is one of a number of disorders associated with the development of a wasting syndrome. The precise mechanisms of this remain unknown, but previous studies have suggested a role for immune and neurohormonal factors. Methods We aimed to investigate in detail the differences in body composition (dual X-ray absorptiometry) and the relationship to candidate biochemical factors of the immune, neurohormonal and metabolic systems in 15 healthy controls, 36 stable non-cachectic and 18 cachectic patients with chronic heart failure. Results Non-cachectic patients showed reduced leg lean tissue (- 9.1%, P<0.01) compared to controls. Cachectic patients had significantly reduced lean (-21.0% vs controls, - 19.9% vs non-cachectics), fat (-33.0% vs controls, -37.0% vs non-cachectics) and bone tissue (-17.5% vs controls, -15.9% vs non-cachectics) (all P<0.0001). Cachectic patients showed a significantly increased cortisol/ dehydroepiandrosterone ratio (+203% vs controls, P<0.0001; +89% vs non-cachectics, P=0.0011) and increased cytokine levels (TNF-alpha, soluble TNF-receptor 1, interleukin-6). The levels of catabolic hormones and cytokines correlated significantly with reduced muscle and fat tissue content and reduced bone mass. Conclusion Peripheral loss of muscle tissue is a general finding in chronic heart failure. The wasting in cardiac cachexia affects all tissue compartments and is significantly related to neurohormonal and immunological abnormalities.