Serum levels of ischemia-modified albumin (IMA) in healthy adults and patients with acute coronary syndrome

Abstract

Introduction: Serum levels of ischemia-modified albumin (IMA) has recently been introduced as an early marker of myocardial ischemia in management of patients with acute coronary syndrome (ACS). The present study aimed to determine the serum IMA levels in healthy adults and ACS patients and also its effectiveness in diagnosing myocardial ischemia.
Material and Method: The serum IMA levels of healthy adults as control group and patients with ACS who had increased myoglobin, troponin T and CK-MB levels during the following 6-24 hours although their cardiac markers were normal initially. Furthermore the effects of age and gender on serum IMA levels were investigated.
Results: There were 196 healthy subjects of which 109 were female (mean age: 48.7 ± 19 years), 87 male (mean age: 44.8 ± 17 years) in the control group. Serum IMA levels were also measured in 41 ACS patients (mean age: 60 ± 13 years, 4 female and 37 male). Serum IMA levels showed a normal distribution in healthy adults. Serum IMA level covering 95% of whole study group was 59.08 ± 13.0 U/mL. Neither gender nor age affected serum IMA levels significantly. Serum IMA levels were significantly higher in ACS patients compared to healthy group (p<0.0001). The cut-off value of serum IMA level for diagnosis of myocardial ischemia was 74.10 U/mL, while the area under ROC curve was 0.8244 (95% Confidence Interval: 0.746 - 0.902, standard error: 0.039, p<0.0001). For the cut-off level of <74.10 U/mL, sensitivity and specificity were 60.98% and 89.29%, respectively. Positive and negative predictive values were 72.7% and 93%, respectively.
Conclusion: The early increments in serum IMA levels following myocardial ischemia and to have a high sensitivity and negative predictive value in diagnosing myocardial ischemia make this test a useful biochemical parameter in diagnosis and treatment of myocardial ischemia..