Letter: Further Considerations on the Clinical Use of the Scottish Inflammatory Prognostic Score in STEMI No-Reflow Prediction

Dear Editor,

We read with great interest the article by Aydın et al, ¹ who evaluated the Scottish Inflammatory Prognostic Score (SIPS) in relation to the no-reflow phenomenon among patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). We congratulate the authors for testing a simple inflammatory-nutritional score in a setting where early, practical risk stratification remains clinically important.

Their results are noteworthy and appropriately nuanced. No-reflow increased stepwise across SIPS categories, yet the score showed only modest discrimination and was not independently associated with no-reflow after adjustment. ¹ This pattern suggests that SIPS captures part of the inflammatory milieu, while also raising a clinically important question: does it add usable information beyond variables that clinicians already consider before and during pPCI?

From this perspective, future work might move from association testing to incremental prediction. Several inflammation-based indices, including the systemic immune-inflammation index, have been associated with no-reflow after pPCI.^2,3 Nevertheless, many individual blood cell- or albumin-based markers perform modestly when used in isolation. A helpful next step would be to compare a conventional model including diabetes mellitus, Killip class, thrombus burden, culprit vessel, and stent length with an otherwise identical model that also includes SIPS. Reporting calibration, net reclassification improvement, integrated discrimination improvement, and decision-curve net benefit could show whether SIPS changes risk categorization or management decisions rather than simply summarizing systemic inflammation.^4,5

The categorical structure of SIPS also deserves attention. Its ease of use is appealing, but fixed thresholds for albumin and neutrophil count may not capture the continuous and time-sensitive inflammatory response in acute STEMI. Analyses of the 2 components as continuous variables, allowing for nonlinearity, could clarify whether risk rises gradually or only beyond clinically meaningful thresholds. Such reporting would also align with current recommendations for transparent prediction-model development and validation. ⁶

In summary, Aydın et al ¹ have opened a useful discussion about SIPS in STEMI-related no-reflow. We believe the score may be most valuable when incorporated into an integrated clinical model and tested prospectively for incremental and decision-making benefit before routine use is considered.

Jiaqi Xu, MMDepartment of Infectious Diseases, the First Teaching Hospital of Tianjin University of TCM, China Qianqian Yang, MMDepartment of Infectious Diseases, the First Teaching Hospital of Tianjin University of TCM, China Xinyi Zhang, MMDepartment of Infectious Diseases, the First Teaching Hospital of Tianjin University of TCM, China Mutian Wang, MDDepartment of Respiratory Medicine, Shanxi Traditional Chinese Medicine Hospital, Taiyuan, China