Association of Neutrophil-to-Lymphocyte Ratio with Cardiovascular and Renal Comorbidities in Isolated Systolic Hypertension: A Cross-Sectional Study

Abstract

Objectives: Isolated systolic hypertension (ISH) is a highly prevalent phenotype of hypertension in older adults and is strongly linked with systemic inflammation. The neutrophil-to-lymphocyte ratio (NLR), an accessible marker derived from complete blood counts, may reflect inflammatory status and predict adverse cardiovascular and renal outcomes. This study aimed to investigate the association between NLR and ISH, and to evaluate its relationship with cardiovascular and renal comorbidities. Methodology: A cross-sectional study was conducted among 300 adults, including 200 ISH patients and 100 age- and sex-matched normotensive controls. Demographic, clinical, and laboratory data were collected. NLR was calculated from absolute neutrophil and lymphocyte counts. Comorbid conditions including cerebrovascular stroke, myocardial infarction (MI), angina, and acute kidney injury (AKI) were identified through clinical assessment and medical records. Statistical analyses included t-tests, chi-square tests, correlation analysis, logistic regression, and ROC curve analysis. Results: Compared to controls, ISH patients had significantly higher WBCs (11.03 ± 3.76 vs. 9.82 ± 2.1 ×10³/μL, p=0.003), neutrophils (6.41 ± 3.29 vs. 3.57 ± 1.49 ×10³/μL, p<0.001), and NLR (3.94 ± 4.27 vs. 1.55 ± 0.83, p<0.001), with lower lymphocytes (2.21 ± 0.91 vs. 2.55 ± 0.8 ×10³/μL, p=0.002). CRP levels were significantly elevated in ISH patients (p<0.001). Cardiovascular and renal comorbidities were more frequent among ISH patients: stroke (38.5% vs. 13%), MI (18.5% vs. 2%), angina (22% vs. 4%), and AKI (33.5% vs. 18%) (all p<0.01). NLR correlated positively with all comorbidities and predicted ISH with an AUC of 0.778 at a cut-off >1.9 (sensitivity 71%, specificity 69%). Conclusion: Elevated NLR is strongly associated with ISH and its cardiovascular and renal comorbidities. As a cost-effective inflammatory marker, NLR may serve as a practical tool for risk stratification in ISH patients.