Validation of surrogate indexes of insulin sensitivity in acute phase of myocardial infarction based on euglycemic-hyperinsulinemic clamp

Abstract

is recognized as a possible contributor to poor patient outcomes. Despite its potential relevance, a standardized and convenient IS assessment tool has yet to be established for said clinical scenarios. This study aimed to validate the accuracy of surrogate indexes in determining IS in acute MI patients by comparison with the gold standard reference method for measuring IS, the euglycemic-hyperinsulinemic clamp (EHC). We performed EHCs in 31 consecutive nondiabetic patients who were admitted within the first 24 h of symptoms of ST-segment elevation MI. Patients with prior diagnosis of diabetes, use of hypoglycemic agents, or a glycosylated hemoglobin Ն6.5% were excluded. EHCs were performed at the second day (D2) and sixth day (D6) post-MI. Basal (12-h fasting) blood samples from D2 and D6 were used to evaluate patient blood glucose and insulin levels. We then calculated the following surrogate indexes: homeostatic model assessment of insulin sensitivity (HOMA2S), homeostatic model assessment of insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI). The IS index measured by EHC (ISiclamp) was correlated to HOMA2S, HOMA-IR, and QUICKI at D2 (r ϭ 0.485, P ϭ 0.009; r ϭ Ϫ0.384, P ϭ 0.048; r ϭ 0.479, P ϭ 0.01, respectively) and D6 (r ϭ 0.621, P ϭ 0.002; r ϭ Ϫ0.576, P ϭ 0.006; r ϭ 0.626, P ϭ 0.002, respectively). Receiver operator characteristic curves made for discrimination of ISiclamp above the median in D2 and D6 depicted areas under the curve of 0.740, 0.734, and 0.760 for HOMA2S, HOMA-IR, and QUICKI, respectively. Bland-Altman plots displayed no apparent systematic error for indexes, but a propensity for proportional error, particularly with HOMA-IR. Thus, based on EHC, these simple surrogate indexes are feasible for assessing IS during MI. homeostatic model assessment; insulin sensitivity; euglycemic hyperinsulinemic clamp; myocardial infarction ELEVATION OF PLASMA GLUCOSE during myocardial infarction (MI) is primarily the result of increased gluconeogenesis and reduced insulin sensitivity (IS) and is strongly related to increased mortality post-MI (2). Aside from the effects of insulin on glucose and lipid metabolism, consistent data demonstrates that it has multiple direct effects on the cardiovascular system as well (4). Insulin has been shown to improve endothelial function and to have both anti-thrombogenic and anti-inflammatory effects (4, 7). Reduced IS has therefore been hypothesized to worsen outcomes of post-MI patients with hyperglycemia. To date, however, the existence of a causal link for this association remains to be proven.The euglycemic-hyperinsulinemic clamp (EHC) has long been considered the gold standard procedure for IS assessment (5). Because of the time-consuming and labor-intensive characteristics of this technique, it is unfeasible to utilize in highrisk patients such as those during the acute phase of MI. Some simplified surrogate indexes have been validated for assessing IS in various situations of metabolic stability (1,9,12,16). However, evidence is...

Definition of new cut-offs of BMI and waist circumference based on body composition and insulin resistance: differences between children, adolescents and adults

“…Accordingly, most data on hypertrophy and its association to insulin resistance in humans were obtained in obese subjects undergoing bariatric surgery . A final argument is that HOMA‐IR most probably reflects hepatic insulin resistance . By contrast, the euglycemic clamp technique, which is considered as the present gold standard in the assessment of insulin sensitivity, measures the stimulation of peripheral, i.e.…”

Acute insulin resistance in ST-segment elevation myocardial infarction in non-diabetic patients is associated with incomplete myocardial reperfusion and impaired coronary microcirculatory function

“…The HOMA index is a simple and inexpensive marker of IR primary used in chronic states. It was recently validated against euglycemic hyperinsulinemic clamp in STEMI patients as feasible for assessing IR during myocardial infarction [ 32 ] and therefore used in the current study.…”

Homeostastic Model Assessment and Insulin Sensitivity/Resistance

“…HOMA-S I /IR have been widely applied, often in large-scale population studies, and frequently compared with other methods of S I determination. Largely, they correlate with more detailed indices of S I (clamp, IVGTT) (11)(12)(13)(14) and in some longitudinal studies (15,16), but less so in others (17), and not as well in some populations such as African American men (18) and Asian-Indian men that include a preponderance of lean diabetic patients (19). In animal models, mice (20) and rats (21) do not do so well with HOMA, but rhesus monkeys do better (22).…”