A nonlinear relationship between systemic inflammation response index and short-term mortality in patients with acute myocardial infarction: a retrospective study from MIMIC-IV

Abstract

BackgroundThis investigation aimed to evaluate the efficacy of the Systemic Inflammatory Response Index (SIRI) in prognosticating short-term all-cause mortality among patients diagnosed with acute myocardial infarction (AMI) in the intensive care unit (ICU).Methods and ResultsClinical data were obtained from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. A total of 4,291 patients were included in the cohort. Results from multivariate regression analyses showed that the quartile of the natural logarithm of SIRI (ln-SIRI) was independently associated with mortality. Compared to patients in the first quartile (Q1), patients in the second quartile (Q2) and fourth quartile (Q4) were significantly associated with an increased risk of 30-day (HR = 2.031, 95% CI: 1.604–2.571, p < 0.001 and HR = 1.703, 95% CI: 1.32–2.195, p < 0.001) and 90-day all-cause mortality (HR = 2.063, 95% CI: 1.68–2.532, p < 0.001 and HR = 1.788, 95% CI: 1.435–2.227, p < 0.001), which is consistent with the results of the Kaplan-Meier analysis and the results of multivariate regression analyses by classifying into 12 groups based on dodeciles of SIRI. Curve fitting showed a curvilinear relationship and further threshold saturation effects showed that, for 90-day mortality, each unit increased in ln-SIRI, when the ln-SIRI level is less than 2.9, the patient's mortality increases by 23.2% (OR: 1.232; 95% CI: 1.111–1.367; p < 0.001); when the ln-SIRI is greater than 2.9 and less than 4.6, the patient's mortality decreases by 44.4% (OR: 0.554; 95% CI: 0.392–0.789; p = 0.001); when ln SIR > 4.6, the patient's mortality increases by 24.7% (OR: 1.247; 95% CI: 1.108–1.404; p < 0.001). Moreover, the length of stay in the hospital was lower in patients in the third quartile (Q3) (coefficient: −1.999; 95% CI: −2.834 – −1.165, p < 0.001). The length of stay in the ICU was higher in patients in Q2 and Q4 (coefficient: 0.685;95% CI: 0.243–1.128; p = 0.0024 and coefficient: 0.989;95% CI: 0.528–1.451; p < 0.001). Furthermore, SIRI may outperform NLR in predicting short-term mortality.ConclusionSIRI is an independent risk factor for 30- and 90-day mortality, and length of stay in ICU for critical AMI patients.

Unraveling the clinical significance and prognostic value of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammation response index, and delta neutrophil index

“…[ 127 ] Another recent study of 2023 investigating the performance of SIRI in patients with acute myocardial infarction with 4291 patients reported that SIRI was also an independent predictor of 30- and 90-day mortality with poor performance (AUC = 0.620, AUC = 0.624, respectively). [ 128 ] Another study examining the performance of SIRI in identifying acute coronary syndrome patients at high risk of a MACE also found that SIRI was an independent predictor of MACE with poor performance (AUC = 0.624). [ 129 ]…”

Association of systemic inflammation response index with mortality risk in older patients with hip fracture: a 10-year retrospective cohort study

“…We then investigated the dose–response relationship using RCS analysis, and the result showed a positive non-linear relationship between SIRI and mortality. This non-linear relationship has also been noted in patients with myocardial infarction ( 24 ), asthma ( 27 ), and heart failure ( 38 ). Furthermore, the inflection points of ln (SIRI) among these studies were 2.9 (SIRI = 18.17) and 4.6 (SIRI = 99.48) for myocardial infarction ( 24 ), and 0.67 (SIRI = 1.95) for asthma ( 27 ).…”

“…Similar results in the full-adjustment models were found in older patients with heart failure for 90-day mortality (second tertile: HR = 1.31; third tertile: HR = 1.41), and 1-year mortality (second tertile: HR = 1.10; third tertile: HR = 1.19) ( 38 ). When patients were divided into four groups according to SIRI quartiles, the association in the second or third quartile lost the statistical significance in other studies ( 24 , 27 , 28 , 39 ). We then investigated the dose–response relationship using RCS analysis, and the result showed a positive non-linear relationship between SIRI and mortality.…”

“…More recently, the system inflammation response index (SIRI) has been considered as a novel marker that comprehensively reflects the balance between host inflammatory and immune status ( 20 ). Emerging studies indicated that high SIRI level was closely associated with poor prognosis in many diseases, including cancer (e.g., liver cancer, prostate cancer) ( 20 , 21 ), cardiovascular disease (e.g., coronary artery disease, myocardial infarction) ( 22 – 24 ), cerebrovascular disease (e.g., stroke, intracerebral hemorrhage) ( 25 , 26 ), respiratory disease (e.g., asthma) ( 27 ), and obesity ( 28 ). The SIRI is calculated from peripheral neutrophil, monocyte and lymphocyte ( 20 ).…”

Systemic Immune-Inflammation Index and Systemic Inflammatory Response Index as Predictors of Mortality in ST-Elevation Myocardial Infarction

“…In a similar population of ACS patients undergoing PCI, SIRI was confirmed as an independent determinant of MACE, which included all-cause mortality and re-hospitalization for severe heart failure, during the follow-up period (median follow-up duration was 1142 days) [ 2 ]. In AMI patients, multivariable Cox regression models evidenced the association between SIRI and short-term mortality (30 and 90 days) [ 9 ]. Both SII and SIRI were found to also be able to predict the risk of in-hospital death in elderly AMI patients [ 10 , 11 ].…”