High plasma HDL-C attenuates stress hyperglycemia during acute phase of myocardial infarction

Objective: During myocardial infarction (MI), a transient decrease of both insulin sensitivity and secretion triggers stress hyperglycemia, which is followed by a substantial increase in mortality. Recent findings in cellular models indicate that HDL may act on glucose homeostasis by improving insulin sensitivity and secretion. In this study, we explored this potential effect in patients during the acute phase of MI. Methods: Plasma glucose, insulin and C-peptide were measured at admission in the first 24 h and on the fifth day after MI with ST-segment elevation in 183 consecutive non-diabetic patients. Patients were divided into HDL-C quartiles for the analyses (Q1: < 31, Q2: 31-38, Q3: 38-47 and Q4: > 47 mg/dL). The Homeostasis Model Assessment version 2 was used to assess insulin sensitivity (HOMA2S) and beta-cell function (HOMA2B). Results: On admission, no difference was found between the quartiles in glucose (p = 0.6), insulin (p = 0.6) or C-peptide (p = 0.5) levels, HOMA2S (p = 0.9) or HOMA2B (p = 1.0). On the fifth day there was a reduction in glucose levels whose intensity was directly proportional to the HDL-C quartile (p < 0.001). At the same time, there was a reduction in plasma insulin (p < 0.001) and C-peptides (p < 0.001) whose magnitude was inversely proportional to the HDL-C quartile. Consistently, the increase of HOMA2S (p < 0.001) and HOMA2B (p = 0.01) were also positively associated with HDL-C levels. Furthermore, plasma HDL-C levels were inversely and independently associated with blood glucose change during the acute phase. Conclusion: This study demonstrates the association between low plasma HDL-C levels and increased duration of stress hyperglycemia during MI and suggests in humans the interaction between HDL and insulin secretion and sensitivity. (C) 2011 Elsevier Ireland Ltd. All rights reserved.