A novel model for predicting the short-term prognosis of acute pulmonary embolism: immuno-inflammatory age-specific shock index model (LogSII-SIA)

Background: To evaluate the forecasting reliability of the systemic immuno-inflammatory index (SII) in combination with the age-specific shock index (SIA) for the near-term prognosis of acute pulmonary embolism (APE) individuals. Methods: The base-10 logarithm was applied to SII, denoted as LogSII. Models were constructed using univariate analysis, Least Absolute Shrinkage and Selection Operator (LASSO) regression for variable selection, and binary logistic regression with 5-fold cross-validation, followed by efficacy analysis. Receiver operator characteristic (ROC) curves and area under the curves (AUC) were plotted, and the forecasting reliability of each indicator was assessed using DeLong’s test. Results: In the original binary logistic regression model (4 variables), LogSII (Odds Ratio (OR) = 6.969, 95%confidence interval (CI): 2.676–18.150, p < 0.001) and SIA (OR = 1.040, 95% CI: 1.013–1.068, p = 0.004) were significant predictors. A simplified model, referred to collectively as Immuno-Inflammatory Age-Specific Shock Index (LogSII-SIA), was subsequently derived: logit (p) = −10.071 + 1.732 × LogSII + 0.052 × SIA. The Hosmer-Lemeshow test indicated a good fit (p = 0.241). The model demonstrated good predictive performance (mean AUC: 0.835 ± 0.080, AUC range: 0.726–0.923), accurate probabilistic prediction (mean Brier score: 0.103) and a low risk of overfitting. The AUC of the simplified pulmonary embolism severity index (sPESI) score was 0.742 (95% CI: 0.687–0.792, p < 0.001). DeLong’s test analysis indicated that the difference between the AUCs of the sPESI score and LogSII-SIA was statistically significant (Z = 1.991, p = 0.0464). Conclusions: LogSII and SIA served as standalone risk factors for the near-term prognosis of APE cases. LogSII-SIA has a higher predictive value for the short-term prognosis of APE than sPESI, and its generalizability needs to be further verified.

Systemic inflammation; Shock index; Simplified pulmonary embolism severity index (sPESI); Acute pulmonary embolism (APE); Prognosis

[1] Freund Y, Cohen-Aubart F, Bloom B. Acute pulmonary embolism: a review. JAMA. 2022; 328: 1336–1345.

[2] Hobohm L, Keller K, Konstantinides S. Pulmonary embolism. Innere Medizin. 2023; 64: 40–49.

[3] Trott T, Bowman J. Diagnosis and management of pulmonary embolism. Emergency Medicine Clinics of North America. 2022; 40: 565–581.

[4] Millington SJ, Aissaoui N, Bowcock E, Brodie D, Burns KEA, Douflé G, et al. High and intermediate risk pulmonary embolism in the ICU. Intensive Care Medicine. 2024; 50: 195–208.

[5] Klok FA, Ageno W, Ay C, Bäck M, Barco S, Bertoletti L, et al. Optimal follow-up after acute pulmonary embolism: a position paper of the European Society of Cardiology Working Group on Pulmonary Circulation and Right Ventricular Function, in collaboration with the European Society of Cardiology Working Group on Atherosclerosis and Vascular Biology, endorsed by the European Respiratory Society. European Heart Journal. 2022; 43: 183–189.

[6] Machanahalli BA, Reddi V, Belford PM, Alvarez M, Jaber WA, Zhao DX, et al. Intermediate-risk pulmonary embolism: a review of contemporary diagnosis, risk stratification and management. Medicina. 2022; 58: 1186.

[7] Leidi A, Bex S, Righini M, Berner A, Grosgurin O, Marti C. Risk stratification in patients with acute pulmonary embolism: current evidence and perspectives. Journal of Clinical Medicine. 2022; 11: 2533.

[8] Wrenn JO, Kabrhel C. Emergency department diagnosis and management of acute pulmonary embolism. British Journal of Haematology. 2024; 205: 1714–1716.

[9] Imiela AM, Mikołajczyk TP, Guzik TJ, Pruszczyk P. Acute pulmonary embolism and immunity in animal models. Archivum Immunologiae et Therapiae Experimentalis. 2024; 72: 1–13.

[10] Ma F, Li L, Xu L, Wu J, Zhang A, Liao J, et al. The relationship between systemic inflammation index, systemic immune-inflammatory index, and inflammatory prognostic index and 90-day outcomes in acute ischemic stroke patients treated with intravenous thrombolysis. Journal of Neuroinflammation. 2023; 20: 220.

[11] Valiente Fernández M, Lesmes González de Aledo A, Delgado Moya FdP, Martín Badía I, Álvaro Valiente E, Blanco Otaegui N, et al. Shock index and physiological stress index for reestratifying patients with intermediate-high risk pulmonary embolism. Medicina Intensiva. 2024; 48: 309–316.

[12] Kara H, Degirmenci S, Bayir A, Ak A. Pulmonary embolism severity index, age-based markers and evaluation in the emergency department. Acta Clinica Belgica. 2015; 70: 259–264.

[13] Gok M, Kurtul A. A novel marker for predicting severity of acute pulmonary embolism: systemic immune-inflammation index. Scandinavian Cardiovascular Journal. 2021; 55: 91–96.

[14] Gökçek K, Gökçek A, Demir A, Yıldırım B, Acar E, Alataş ÖD. In-hospital mortality of acute pulmonary embolism: predictive value of shock index, modified shock index, and age shock index scores. Medicina Clínica. 2022; 158: 351–355.

[15] Korkut M, Yavuz A, Selvi F, Zortuk Ö, İnan EH, Güven HÇ. Prognostic performance of the Bova, sPESI, and Qanadli scores in patients with acute pulmonary embolism. Acta Radiologica. 2024; 65: 1482–1490.

[16] Ali H, Shahzad M, Sarfraz S, Sewell KB, Alqalyoobi S, Mohan Babu P. Application and impact of lasso regression in gastroenterology: a systematic review. Indian Journal of Gastroenterology. 2023; 42: 780–790.

[17] Kong Y, Lin M, Fu Y, Huang B, Jin M, Ma L. Elevated log uric acid-to-high-density lipoprotein cholesterol ratio (UHR) as a predictor of increased female infertility risk: insights from the NHANES 2013–2020. Lipids in Health and Disease. 2025; 24: 127.

[18] Gao C, Bian X, Wu L, Zhan Q, Yu F, Pan H, et al. A nomogram predicting the histologic activity of lupus nephritis from clinical parameters. Nephrology Dialysis Transplantation. 2024; 39: 520–530.

[19] Sifuentes AA, Goldar G, Abdul-Aziz AAA, Lee R, Shore S. Mechanical circulatory support and critical care management of high-risk acute pulmonary embolism. Interventional Cardiology Clinics. 2023; 12: 323–338.

[20] El-Bouri WK, Sanders A, Lip GYH; BBC-VTE investigators. Predicting acute and long-term mortality in a cohort of pulmonary embolism patients using machine learning. European Journal of Internal Medicine. 2023; 118: 42–48.

[21] Li S, Huang S, Feng Y, Mao Y. Development of a nomogram model to predict 30-day mortality in ICU cancer patients with acute pulmonary embolism. Scientific Reports. 2025; 15: 9232.

[22] Tan I, Barin E, Butlin M, Avolio AP. Relationship between heart rate and central aortic blood pressure: implications for assessment and treatment of isolated systolic hypertension in the young. Minerva Medica. 2022; 113: 807–816.

[23] Baffour-Awuah B, Man M, Goessler KF, Cornelissen VA, Dieberg G, Smart NA, et al. Effect of exercise training on the renin-angiotensin-aldosterone system: a meta-analysis. Journal of Human Hypertension. 2024; 38: 89–101.

[24] Vakhshoori M, Bondariyan N, Sabouhi S, Shakarami M, Emami SA, Nemati S, et al. Impact of shock index (SI), modified SI, and age-derivative indices on acute heart failure prognosis; a systematic review and meta-analysis. PLOS ONE. 2024; 19: e0314528.

[25] Mandel J, Casari M, Stepanyan M, Martyanov A, Deppermann C. Beyond hemostasis: platelet innate immune interactions and thromboinflammation. International Journal of Molecular Sciences. 2022; 23: 3868.

[26] Viswanathan G, Kirshner HF, Nazo N, Ali S, Ganapathi A, Cumming I, et al. Single-cell analysis reveals distinct immune and smooth muscle cell populations that contribute to chronic thromboembolic pulmonary hypertension. American Journal of Respiratory and Critical Care Medicine. 2023; 207: 1358–1375.

[27] Luijten D, de Jong CMM, Ninaber MK, Spruit MA, Huisman MV, Klok FA. Post-pulmonary embolism syndrome and functional outcomes after acute pulmonary embolism. Seminars in Thrombosis and Hemostasis. 2023; 49: 848–860.

[28] Jiang C, Lin J, Xie B, Peng M, Dai Z, Mai S, et al. Causal association between circulating blood cell traits and pulmonary embolism: a mendelian randomization study. Thrombosis Journal. 2024; 22: 49.

[29] Lange T, Luebber F, Grasshoff H, Besedovsky L. The contribution of sleep to the neuroendocrine regulation of rhythms in human leukocyte traffic. Seminars in Immunopathology. 2022; 44: 239–254.

[30] Bedel C, Korkut M, Armağan H. Can NLR, PLR and LMR be used as prognostic indicators in patients with pulmonary embolism? A commentary. Bosnian Journal of Basic Medical Sciences. 2021; 21: 501.