Association of red blood cell distribution width, systemic-immune-inflammation index and poor cardiovascular outcomes in patients with newly diagnosed hypertension

Background: Red cell distribution width (RDW) and the systemic immune-inflammation index (SII) have been extensively studied as predictors of morbidity and mortality in several cardiovascular diseases. This prospective study aimed to investigate the relationship between long term major adverse cardiac events (MACEs) and simple hematological parameters in hypertensive patients. Methods: The study included a total of 1202 patients with newly diagnosed HT. Of the patients, 662 (55.1%) were female and 540 (44.9%) were male, with a mean age of 53.0 ± 11.4 years. The primary endpoint of the study was long term MACE, including cardiac death, stroke, and myocardial infarction. This is the first study focusing on the association of SII with major adverse cardiovascular outcomes in patients with HT. Results: Eighty-nine patients (8.7%) developed at least one MACE during a mean follow-up period of 82.2 ± 1.3 months. RDW (13.0 ± 0.9 vs. 13.5 ± 1.2%, p < .001) and SII [465.0 (353.4–609.4) vs. 584.4 (468.9–794.0) x10³/µL, p < .001] were significantly higher in patients with MACEs. The prevalence of MACEs was significantly higher in patients with RDW>13.1% (10.4 vs. 5%; p < .001) and in patients with SII>465 x10³/µL (11.8 vs. 3.1%; p < .001). The multivariate logistic regression analysis showed SII and RDW were independent predictors of MACEs. Conclusion: The results of the study demonstrated that the RDW and SII were independent predictors of long-term cardiovascular events in hypertensive patients. These simple hematological parameters may be used as prognosticators of MACE in patients with newly diagnosed HT.