Evaluation of the Relationship Between Systemic Immune-Inflammatory Index and Morning Blood Pressure Surge in Newly Diagnosed Essential Hypertension Patients

Purpose: This study aims to explore the relationship between the Systemic Immune-Inflammatory Index (SII) and Morning Blood Pressure Surge (MBPS) in patients with newly diagnosed essential hypertension. Materials and Methods: A cross-sectional study was conducted between April and June 2024, involving 405 participants, 217 controls, and 188 hypertensive patients, recruited from a cardiology outpatient clinic. Participants' blood pressure was monitored using Ambulatory Blood Pressure Monitoring (ABPM), and inflammatory markers, including SII, were assessed. SII was calculated by multiplying platelet count by neutrophil count and dividing by lymphocyte count. Statistical analysis included ROC curve analysis to evaluate SII's predictive value for MBPS. Results: Hypertensive patients exhibited significantly higher 24-hour, daytime, and nighttime systolic and diastolic blood pressure values compared to controls (all p<0.001). MBPS and SII were also significantly elevated in the hypertensive group (both p=0.003). ROC analysis demonstrated that SII had an AUC of 0.645 (p=0.001) with a sensitivity of 56.4% and specificity of 67% at a cut-off value of 577.38 for predicting MBPS greater than 27.3 mmHg. Elevated neutrophil and platelet counts were associated with higher blood pressure levels and cardiovascular risk. Conclusion: The study identified a significant association between SII and MBPS in hypertensive patients, suggesting that systemic inflammation may play a role in the regulation of blood pressure and the pathogenesis of hypertension. SII could serve as a valuable biomarker for predicting MBPS and associated cardiovascular risks, facilitating earlier and more targeted interventions.