Associations of novel blood-derived markers of inflammation with blood pressure, arterial stiffness and heart rate in young adults

Background Although C-reactive protein (CRP) is often used to assess inflammation and can predict higher BP and arterial stiffness, novel measures of inflammation derived from platelets, white blood cell (WBC) counts, and high-density lipoprotein cholesterol (HDL-C) may also indicate possible hypertension and arterial stiffening. Methods We assessed the association for CRP and novel inflammatory markers with clinic BP, arterial stiffness, and heart rate (HR) in Gen2 Raine Study participants in Western Australia at age 17 and 22 years. Arterial stiffness was assessed using pulse-wave velocity (PWV), the augmentation index (AIx) and pulse pressure (PP). Inflammatory markers included high-sensitivity (hs)-CRP, hsCRP-to-albumin ratio, lymphocyte, monocyte, neutrophil, and platelet counts, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, mean platelet volume, the neutrophil percentage-to-albumin ratio, the monocyte/HDL-C ratio, the neutrophil/HDL-C ratio, the Prognostic Nutritional Index and the Systemic Inflammation Index (SII). Analysis adjusted for age, gender, waist-to-hip ratio, family history of hypertension, diet, physical activity, smoking and alcohol consumption. Results Males (N=363) had higher systolic BP (Δ=9.1mmHg; 95% CI=7.9-10.3, p<0.001), lower diastolic BP (Δ=−0.9mmHg; 95% CI=−1.8, −0.1, p<0.001) and higher PWV (Δ=0.37m/sec; 95% CI=0.26 to 0.48, p<0.001) than females (N=330). Lymphocyte count, the monocyte/HDL-C ratio and the neutrophil/HDL-C ratio were each significantly and positively associated with SBP, PP and the AIx. Platelet count was significantly and positively associated with SBP, DBP and PP. Nine of the 14 inflammatory indices were associated with HR, and associations for SBP, DBP, AIx and PWV were mostly stronger for males than for females. hsCRP and the SII were not associated with any of SBP, DBP, PP, AIx or PWV. Conclusions Lymphocyte count, the monocyte/HDL-C ratio, the neutrophil/HDL-C ratio, and platelet count may represent better markers of inflammation related to higher BP in young adults than CRP and the SII. The positive associations with arterial stiffness and HR, and the stronger associations for males also provides insight into potential mechanisms.