The predictive value of systemic immune-inflammation index for long-term cardiovascular mortality in non-ST segment elevation myocardial infarction.

Background: Increased levels of inflammatory markers have been found in association with the severity of coronary atherosclerosis. Systemic immuneinflammation index (SII), which is calculated by multiplying neutrophil and platelet counts and then dividing the result by the lymphocyte count, can also be used as a prognostic indicator in different cardiovascular diseases. In this study, we investigated SII levels and long-term mortality of patients with non-ST segment elevation myocardial infarction (NSTEMI).

Methods: This is an observational, single-center study. Two hundred-eight patients who underwent coronary angiography for NSTEMI were included in the study. Patients were divided into 3 tertiles based on SII levels. We researched the relationship between level level and 1, 3 and 5 years mortality (NSTEMI).

Results: One-year mortality of the patients was significantly higher among patients in the upper SII tertile when compared with the lower and middle SII tertile groups [11 (15.9%) vs. 2 (2.9%) and 6 (8.7%); P  = 0.008, P  = 0.195, respectively). Three-year mortality of the patients was significantly higher among patients in the upper SII tertile when compared with the lower and middle SII tertile groups [21 (30.4%) vs. 5 (7.1%) and 12 (17.4%); P  < 0.001, P  = 0.072, respectively). Five-year mortality of the patients was significantly higher among patients in the upper SII tertile when compared with the lower and middle SII tertile groups [26 (37.7%) vs. 8 (11.4%) and 15 (21.7%); P  < 0.001, P  = 0.040, respectively).

Conclusion: Our study showed that NSTEMI patients with higher SII had worse long-term mortality.