HBA1c Levels In Non-Diabetic Patients with ST Elevated Myocardial Infarction & its Correlation with Short Term Mortality

Background: Elevated HBA1C level is predictive for cardiovascular disease and mortality in diabetic & also in nondiabetic patients. Aim of our study was to evaluate correlation between HBA1c on admission and short term mortality in non-diabetic patients with ST elevated myocardial infarction. Methods: 266 non-diabetic patients presenting with STEMI (within 48 hours) were included in our study. Data regarding patient characteristics were collected over 7 months. All-cause mortality data collected prospectively up to 6 months. Results: Mean HBA1C was 5.69±0.65 for the study population. HBA1C quartiles (<5, 5.1-5.5, 5.6-6, 6.1-6.4) has shown increased 6 months mortality (3%, 4.8%, 1.7%, 15.1% respectively P=0.004) with increased values. Multivariate regression analysis has shown HBA1C>6 as an independent predictor of 6 month mortality. Conclusion: A significant correlation exists between HBA1C on admission in non-diabetic patients with STEMI and 6 month all-cause mortality.

Acute glycometabolic derangement in non-diabetic patients with myocardial infarction is a powerful predictor of prognosis. Elevated HBA1C levels are predictive for cardiovascular disease and mortality in patients without DM indicating that long-term glycometabolic derangement in the sub diabetic range also poses a risk for cardiovascular disease [1] A recent report by Timmer JR et al has found that increase in HbA1c levels was predictive of cardiovascular disease and mortality in patients without diabetes mellitus [2].Increasing HbA1c levels were clearly associated with adverse baseline characteristics such as a higher cardiovascular risk profile, explaining part of the increase in long-term mortality. Among non-diabetic adults attended in a second visit of the Atherosclerosis Risk In Communities (ARIC) study, higher HbA1c level was associated with higher cardiovascular disease and death [Selvin et al. 2010]. In the Rancho Bernardo cohort [3] of 1239 older non-diabetic adults, baseline HbA1c but not fasting or post-challenge glucose predicted cardiovascular mortality in women but not in men. In addition, it is conceivable that part of the association between long-term abnormalities in glucose control and outcome is due to the same complex mechanisms responsible for the adverse association between overt diabetes mellitus and cardiovascular outcome. Indeed, it has been well established that the excess risk for developing coronary artery disease is not limited to patients with diabetes mellitus but also is present in impaired fasting glucose, impaired glucose tolerance, and other states of insulin resistance. Pai et al. [4], conducted parallel nested case-control studies in 2 cohorts of US health professionals, in non-diabetic women (Nurses' Health Study) and men (Health Professionals Follow-up Study) and found that compared with HbA1c of 5.0% to <5.5%, those with an HbA1c of 6.0% to <6.5%, the pooled relative risk of CAD was 1.29 (95% CI 1.11-1.50) for every 0.5%increment increase in HbA1c levels and 1.67 (95% CI 1.23-2.25) for every 1%-increment increase, with the risk plateauing around 5.0%. Furthermore, participants with HbA1c levels between 6.0% and <6.5% and CRP levels >3.0 mg/l had a 2.5-fold higher risk of CAD compared with participants in the lowest categories of both biomarkers. A recent meta-analysis also examined the association between HbA1c and risk of CAD in people without diabetes. The European guidelines on diabetes mellitus, prediabetes, and cardiovascular disease recommend that people at high risk for type 2 diabetes mellitus should receive lifestyle counselling and, if needed, pharmacological therapy to reduce their risk of developing overt hyperglycaemia and type 2 diabetes mellitus especially to prevent or slow the development of cardiovascular disease. This approach could also be encouraged in our patient population, and it may alter prognosis. However, it is known that the overall increase in cardiovascular risk in patients with diabetes mellitus or milder abnormalities in glucose levels is not explained by abnormalities in

International Journal of Clinical Case Reports and Reviews
Arnab ghosh chaudhury AUCTORES Globalize your Research glucose or HbA1c alone, which is an important consideration in designing prevention efforts.
Hyperglycaemia is common during AMI, and may be a result of stress-induced catecholamine release or previously unidentified diabetes mellitus. Glycated haemoglobin (HbA1C) is a measure of glycaemia over the preceding months, and may be helpful in detecting abnormalities of glucose tolerance as there is an inverse relationship between HbAlc and glucose tolerance. Acute glycometabolic derangement in non-diabetic patients with myocardial infarction has already been proven to be a powerful predictor of prognosis by Goyel A et al [5]. Until now, data on the predictive value of HbA1c levels, reflecting long-term glycometabolic control, in non-diabetic patients with myocardial infarction are limited as observed by Hudjaj et al in his article [6]. In this background, we have conducted our study on HbA1C levels in blood on admission in nondiabetic patients presented with STEMI and its correlation with short term all-cause mortality.

Objective:
To evaluate correlation between HBA1c levels in blood on admission and short term mortality in non-diabetic patients with ST elevated myocardial infarction.

Materials and Methods:
Our study was a single centre (SJIC&R) observational (cross sectional) study with short term follow up (6 months) Period of data collection was from August 2016 to February 2017(7 months). A proforma was predesigned for data collection. Written informed consent was taken from the study participants. Study consisted of history, study of angiographic report and relevant biochemical investigations. It consisted of patient details like hospital number, name, age, gender, history of diabetes, smoking, dyslipidemia, hypertension and other co-morbidities. Definitions used were as follows: Details of the angiography were obtained and weighed using SYNTAX score. The SYNTAX scores were calculated with the help of professional website tool: http://www.syntaxscore.com/. Serum concentration of HbA1c was determined by immunoturbidometric method. Mortality data (All-cause mortality) was collected prospectively. It included in hospital mortality & mortality after 6 months.   Table 3: Multivariate Logistic regression analysis to assess the risk factors of 6 month all-cause mortality reported that elevated HbA1c levels predict cardiovascular disease and mortality in patients without diabetes, indicating that even milder abnormalities of glucose control below the diagnostic threshold of diabetes mellitus also pose a risk of development of cardiovascular disease. In the communitybased Atherosclerosis Risk in Communities study [8] that involved nondiabetic participants, baseline HbA1c levels of 5.5% to less than 6.0%, 6.0% to less than 6.5%, and 6.5% or greater were associated with increasing risk of the development of coronary heart disease compared with those with HbA1c levels of 5.0% to 5.5%. Our findings are in accordance with the results of most of these studies. In our study population, increasing HbA1c levels were clearly associated with higher cardiovascular risk profile, which explains part of the increased risk. In addition, it is conceivable that the same complex mechanisms that are responsible for the adverse association between overt diabetes and cardiovascular outcome (ie, oxidative stress, protein glycation of the vessel wall, and endothelial dysfunction) also play an active role in chronic hyperglycaemia even in the sub-diabetic range. It is also possible that high baseline HbA1c levels represent patients who are at high risk for developing diabetes in the future, thus increasing the risk of developing CAD. However, because our study was cross-sectional, we were unable to assess this hypothesis. There is enough evidence to conclude that strategies to prevent diabetes also reduce the risk of CVD. Hence, as practiced in patients with diabetes mellitus, an intensive multifactorial approach should be used to prevent CVD in pre-diabetic patients. [9] Trans-professional collaboration between cardiologists and diabetologists and a multifactorial and target-driven approach are highly rewarding. [10] Elevated HbAlc was found to be associated with an increased mortality in non-diabetic subjects suffering an AMI. This finding is similar to the finding in the study by TA Chowdhury et al [11]. In our study HBA1C>6 is identified as an independent predictor of 6 month mortality similar to the study by TA Chowdhury et al [11].
For a wide range of known cardiovascular risk factors, we cannot rule out the possibility of residual confounding variables in this observational study.

Conclusion:
1. A significant correlation exists between HBA1C level in non-diabetic STEMI patients & all-cause mortality at 6 months. 2. HBA1C>6.0 has proven to be an independent predictor of all-cause mortality at 6 months in non-diabetic STEMI patients.