Glucose and insulin abnormalities relate to functional capacity in patients with congestive heart failure

Aims In addition to diabetes mellitus, less severe abnormalities of glucose and insulin metabolism may be related to functional status in patients wit h heart failure. We examined the relationship of hyperglycaemia (greater th an or equal to 6.1 mmol.l(-1)) and hyperinsulinaemia (greater than or equal to 11.2 mU.l(-1)) to functional status and cardiac function in patients wi th heart failure. Methods and Results Fasting plasma glucose and insulin levels were obtained in 663 heart failure patients. The average left ventricular ejection fract ion was 0.28 +/- 0.07, 63% were in New York Heart Association Functional Cl ass (NYHA-FC) I/II and 37% were in NYHA-FC III/IV. Twenty seven percent had diabetes mellitus, but an additional 8% had undiagnosed diabetes mellitus (glucose greater than or equal to 7 mmol.l(-1)) and 9% had glucose levels b etween 6.1 and 7 mmol.l(-1), so that a total of 43% (287) of patients had e levated glucose levels (greater than or equal to 6.1 mmol.l(-1)). In genera l, more diabetic patients had NYHA-FC III/IV symptoms, shorter 6 min walk d istances, but similar left ventricular ejection fractions compared to non-d iabetic patients. The non- diabetic patients in NYHA-FC III/IV had higher g lucose and insulin levels than patients in NYHA-FC I/II(6.3 +/- 0.2 vs 5.6 +/- 0.1 mmol.l(-1), P<0.001 and 19.6+/-2.3 vs 10.2 +/- 0.6 mU.l(-1), P<0.00 1). Non-diabetic patients with elevated glucose levels had shorter 6 min wa lk distances compared to those with normal glucose levels (368.2 +/- 8 m vs 389 +/- 4 m, P=0.02), however, left ventricular ejection fraction was simi lar. Conclusion Glucose abnormalities are extremely common in heart failure pati ents (43% of patients). Diabetes mellitus and hyperglycaemia or hyperlinsul inaemia in non-diabetic patients were related to worse symptomatic status b ut not worsening left ventricular ejection fraction compared to patients wi th normal glucose and insulin levels. (C) 2000 The European Society of Card iology.