Objective: To evaluate the relationship between pulse pressure index (PPI) and carotid intima-media thickness (CIMT).
Method: Observational trial was design and 342 patients newly diagnosed as hypertension without anti-hypertensive therapy were enrolled. According to the cut-off value of CIMT, 342 participants were divided into normal (< 0.9mm) and increased CIMT groups (≥ 0.9mm). Baseline characteristics were compared, logistic regression analysis and receiver operating characteristic curve (ROC) were performed.
Results: Approximately 34.2% of participants (n = 117) were with CIMT ≥ 0.9 mm and participants in increased CIMT group were more elderly. Diastolic blood pressure was lower in increased CIMT group than normal group (79.3 ± 10.8 mm Hg versus 83.8 ± 9.4 mm Hg, p < 0.001), whereas pulse pressure (PP) (59.3 ± 20.2 mm Hg versus 53.6 ± 15.5 mm Hg, p = 0.004) and PPI (0.43 ± 0.09 versus 0.38 ± 0.08, p < 0.001) were significantly higher in increased CIMT group. CIMTs were 1.11 ± 0.11 mm and 0.76 ± 0.12 in increased group and normal group respectively (p < 0.001). After adjusted for the traditional risk factors, only PPI was found an independent determinant for CIMT increase, and the odd ratio was 1.644 (95% interval confidence 1.280-2.112, p < 0.001). The ROC evaluations showed that area under the curve for PP to predict CIMT increase was 0.591 ± 0.034, and PPI was 0.664 ± 0.033. PPI was more powerful than PP in discriminating CIMT increase (p = 0.006).
Conclusion: PPI is a valuable parameter for the preliminary screening of hypertensive patients who have an increased risk of atherosclerosis.
Keywords: Essential hypertension; pulse pressure; pulse pressure index.