DEFICIENT INSULIN-LIKE-GROWTH-FACTOR-I IN CHRONIC HEART-FAILURE PREDICTS ALTERED BODY-COMPOSITION, ANABOLIC DEFICIENCY, CYTOKINE AND NEUROHORMONAL ACTIVATION

Background. Recent studies of growth hormone supplementation in chroni c heart failure have been associated with variable results. Acquired a bnormalities of biochemical parameters of the growth hormone insulin-l ike growth factor I axis have been associated with severe chronic hear t failure. There are suggestions of an acquired growth hormone resista nce with deficient insulinlike growth factor I in some patients. Objec tives. Therefore, we set out to investigate the clinical and Functiona l status and the degree of cytokine and neurohormonal alteration of ch ronic heart failure patients with deficient insulinlike growth factor I responses. Methods. Patients with chronic heart failure were divided into tno groups according to their insulin-like growth factor I level s (classified according to the manufacturer's assay range in normal co ntrols): low insulin-like growth factor I <104 (n = 20; 89 +/- 9.6 ng/ ml), and normal/high >104 ng/ml (n = 32; 169 +/- 52 ng/ml). Between gr oups there was no difference in age (low versus high: 65.3 +/- 12.1 ve rsus 61.6 +/- 9.1 gears, p = 0.21), body mass index, aerobic capacity (peak oxygen consumption: low versus high: 15.5 +/- 5.2 versus 17.3 +/ - 6.3 mL/kg/min, p = 0.23), left ventricular ejection fraction, New Yo rk Heart Association classification. Results. During quadriceps streng th testing, patients with low insulin-like growth factor I had reduced absolute strength (-24%), and strength per unit area muscle (-14%) th an patients with normal/high insulin-like growth factor I. Leg muscle cross-sectional area was lower in the low insulin-like growth factor I group (-12% and -13% for right and left legs, respectively). These al terations were accompanied by increased levels of growth hormone (+145 %), tumor necrosis factor-alpha (+46%), cortisol/ dehydroepiandrostero ne ratio (+60%), noradrenaline (+49%) and adrenaline (+136%) tall at l east p < 0.05). Conclusions. Patients with low insulin-like growth fac tor I levels show signs of altered body composition, cytokine and neur oendocrine activation, to a greater extent than patients with normal/h igh levels. (C) 1998 by the American College of Cardiology.