Journal of Clinical and Diagnostic Research. 2021 Dec, Vol-15(12): OC11-OC15 11 11 DOI: 10.7860/JCDR/2021/51766.15719 Original Article General Medicine Section Role of Neutrophil-lymphocyte Ratio as Short- term Outcome Prognostic Indicator Following an Acute ST Segment Elevation Myocardial Infarction-A Prospective Observational Study INTRODUCTION Cardiovascular Diseases (CVDs) that include IHD and stroke account for 17.7 million deaths and are leading causes of death [1]. In India the prevalence of coronary artery disease is 21.4% for diabetics and 11% for nondiabetics and this prevalence in rural population is half than that in urban population [2]. IHD comprises of Silent Ischemia (SI), Stable Angina Pectoris (SAP) and Acute Coronary Syndromes (ACS) [3]. The acute manifestation of IHD is ACS, subdivided into sudden cardiac death, Non ST Segment Elevation ACS (NSTE ACS) and STEMI. The NSTE ACS is further subdivided into NSTEMI and Unstable Angina Pectoris (UAP) [3,4]. Inflammation has shown to underlie many CVDs, especially those involving atherosclerosis as a pathogenic mechanism, such as coronary artery disease [3,4]. Lymphocytes and monocytes are found in the early phases of plaque formation, whereas neutrophils are involved in acute plaque disruption and thrombotic occlusion. The atherosclerotic plaque is formed under the direction of activated monocytes, sections of blood platelets, proliferating endothelial cells and foam cells (from unsafe Low Density lipoprotein Cholesterol or LDL-C). The neutrophils which release Reactive Oxygen Species (ROS), oxidise LDL-C and contribute to plaque disruption. In established atheromata, the neutrophils undergo apoptosis and thereby the migration of monocytes/macrophages occurs into the site to maintain function of phagocytosis [4]. Inflammatory markers such as C-Reactive Protein (CRP) and neutrophil rise in the acute phase of cardiac diseases such as Acute Heart Failure (AHF), and ACS (especially in STEMI) is an established phenomenon [5,6]. Studies have observed that various haematological indices such as total leukocyte count, neutrophil count and NLR are predictive of survival in STEMI [7-9]. NLR ratio can be calculated as the absolute count of neutrophils divided by the total count of lymphocytes. NLR has been proved to be a useful prognostic indicator in various conditions like major cardiac events, cancers, infectious diseases and postoperative complications. In a study by Forget P et al., the normal NLR value in adult, non geriatric healthy population was between 0.73 and 3.53 [10]. NLR is an inexpensive, widely available test and can be easily calculated in comparison to other inflammatory markers in developing countries such as India. Given the paucity of NLR based survival prediction studies, occurrence of higher frequency of STEMI in Indian population, and because STEMI is associated with high early and late morbidity and mortality [11], the current study was undertaken. Also, the documented NLR could contribute to future risk stratification of admitted patients with acute STEMI [12,13]. The previous studies also support the role of NLR in predicting complications and death in myocardial infarction patients [14-16]. Thus, prognostic value of NLR in STEMI with respect to survival outcomes was evaluated in the present study. MATERIALS AND METHODS A hospital based short-term prospective observational study was conducted under the Department of General Medicine in a tertiary care hospital (MS Ramaiah Medical College, Bengaluru, Karnataka, India) from October 2015 to September 2017. The study was approved by Institutional Ethics and Scientific committee, prior to the start of the study (Reference number: STD-1/EC/027/2015). A written informed consent was obtained from all the participants before starting the study. Sample size calculation: The study was conducted on a sample of 102 participants. In the present study, sample size was calculated, assuming the sensitivity of NLR in predicting in-hospital mortality after STEMI to be 60%, with the precision of 1.5% and desired confidence level of 95% based on a previous study by Ghaffari S et al., [14]. CATHERINE T PAUL 1 , VIJAYASHREE THYAGARAJ 2 , SWATI HEGDE 3 Keywords: Acute coronary syndrome, Complication, Morbidity, Mortality, Prognosis ABSTRACT Introduction: The ratio of Neutrophils to Lymphocytes (NLR) has recently arisen as a likely biomarker to forecast clinical outcomes in Ischaemic Heart Disease (IHD). The NLR in cases of ST Elevation Myocardial Infarction (STEMI) with respect to survival outcomes and complications is not well established in literature and was evaluated in the present study. Aim: To study the association of NLR with complications and mortality following acute STEMI. Materials and Methods: A short-term prospective observational study was conducted in 102 participants diagnosed with STEMI. The study was conducted at tertiary care hospital from October 2015 to September 2017. Haematological, serological and radiographical findings were obtained and compared between survivors and non survivors. Receiver Operator Curve (ROC) and Area Under the Curve (AUC) analysis were performed to analyse the utility of NLR in predicting mortality and major complications. Results: The mean age of patients was 64.12±14.82 years and 75.5% of them were male. Non survivors (9.8%) had a greater incidence of cardiogenic shock (p-value <0.00049), pulmonary oedema (p-value <0.01199) and tachyarrhythmia (p-value <0.00049) compared to survivors. The ROC and AUC analysis showed that a higher NLR had a sensitivity of 80% in detecting mortality, 77.78% in detecting cardiogenic shock and 80% in detecting pulmonary oedema. Conclusion: Higher NLR can be a useful prognostic marker for predicting short-term mortality and acute complications following an acute STEMI.