Association of peripheral CD4⁺/CD8⁺ T-cell ratio with SYNTAX score and coronary stenosis severity in patients with coronary artery disease.

Abstract

Background: Coronary Artery Disease (CAD) is characterized by chronic immune-inflammatory activation. The relationship between the peripheral CD4+/CD8+ T-cell ratio and coronary stenosis severity remains unclear. We investigated its association with SYNTAX score and potential as a complementary marker.

Methods: CD4+ and CD8+ T-cell counts were measured by flow cytometry in 297 patients with CAD and 181 controls. Coronary stenosis was assessed by angiography and SYNTAX score. Multivariable linear regression was used for SYNTAX score, and logistic regression for moderate-to-severe stenosis (SYNTAX > 23). Models were adjusted for age, sex, BMI, hypertension, diabetes, smoking, HbA1c, hs-CRP, creatinine, and medications. Benjamini-Hochberg FDR was applied. ROC analysis assessed incremental value beyond risk factors.

Results: CD4+ counts and the CD4+/CD8+ ratio were higher, and CD8+ counts lower, in CAD patients, especially in acute coronary syndromes. In unadjusted analyses, SYNTAX score correlated positively with CD4+ count and the CD4+/CD8+ ratio and negatively with CD8+ count (weak to moderate). After adjustment, the CD4+/CD8+ ratio remained independently associated with SYNTAX score (β = 4.88, 95% CI 1.42-8.30, p = 0.006). For SYNTAX > 23, the ratio showed limited discrimination (AUC = 0.598, 95% CI 0.526-0.670; sensitivity 0.587, specificity 0.552 at cutoff 1.90). Adding the ratio to conventional risk factors showed no substantial incremental value (ΔAUC = 0.010, DeLong p = 0.43, NRI = 0.082, IDI = 0.006).

Conclusions: Peripheral T-cell imbalance is associated with greater angiographic coronary complexity in CAD. However, the CD4+/CD8+ ratio has limited discriminatory ability and should be considered a complementary candidate marker, not a standalone diagnostic or predictive tool. Larger prospective multicenter studies are required.