A STUDY ON THE PROGNOSTIC SIGNIFICANCE OF HYPONATREMIA IN ACUTE MYOCARDIAL INFARCTION- A PROSPECTIVE LONGITUDINAL STUDY

Abstract

Background: Hyponatremia, dened as a serum sodium concentration <135 mEq/L, is the most common electrolyte disorder in hospitalized patients. Hyponatremia also increases the morbidity and mortality following myocardial infarction. MI is a major cause of death and is a global health problem reaching epidemic in both developed as well as in developing countries. Aims and Objectives: To study hyponatremia as a prognostic marker in patients with acute myocardial infarction-STEMI and NSTEMI. Material and Methods: This prospective, longitudinal observational study was conducted during December 2018 – October 2020 in 152 cases of acute MI. Results: Male preponderance in the patients hospitalised due to acute MI was 73.03%. The mean age of females was 59.46±9.42 years affected by acute MI was more than males i.e. 53.23±9.92 years. Hyponatremia was present in 39.47% of the cases with acute MI. Mild hyponatremia was the most prevalent 71.67% and severe hyponatremia was the least prevalent 3.33%. Diabetes mellitus was more prevalent in cases of MI with hyponatremia 53.33% vs 25%. The GRACE scores were higher in the cases having hyponatremia and increases with the increase in severity of hyponatremia. The TIMI scores were higher in the cases having hyponatremia and increases with the increase in severity of hyponatremia. The mean duration of hospital stay was 9.99 ± 8.69 days. STEMI was more prevalent 75.66% than NSTEMI. AWMI cases were more in the population with hyponatremia 78% than in the population with normal serum sodium 53.85%. Acute MI cases with hyponatremia had lower mean LVEF than those with normal serum sodium levels. Primary reperfusion therapy (thrombolysis/primary PCI) was done in 44.08% of the cases and no signicant association was found between it and outcomes in the hyponatremia group. Complications were present in 23.03% of the cases in hyponatremia group (p <0.05). Mortality was present in 2.64% of the cases and more common in the cases with hyponatremia (p>0.05). The odds of complications (including death) was 2.91 times in the cases with hyponatremia as compared to cases with normal serum sodium levels, 2.47 times in the cases with mild hyponatremia as compared to cases with normal serum sodium levels, 3.42 times in the cases with moderate hyponatremia as compared to cases with normal serum sodium levels and 25 times in the cases severe hyponatremia as compared to cases with normal serum sodium levels. Conclusion: It can be concluded that the severity of MI is more in cases with hyponatremia and hyponatremia is associated with poorer outcomes in terms of complications post MI and mortality.