Relationships Between Arterial Pressure-Volume Index and Cardiovascular Disease Biomarkers in Patients With Hypertension

Abstract

Background: The arterial pressure-volume index (API), which is obtained by conventional blood pressure measurement, is a new marker for arterial stiffness. The aim of this study was to clarify the relationships between the API and various clinical parameters, including cardiovascular disease (CVD) biomarkers, in patients with hypertension for the prevention of CVD.

Methods: This cross-sectional study enrolled 288 patients with hypertension receiving pharmacological treatment, without a history of CVD (males/females: 115/173; age: 63 ± 11 years (mean ± standard deviation)). The API was automatically calculated using a commercial device.

Results: The API was significantly correlated with important CVD biomarkers, such as the concentration of urinary albumin (r = 0.42, P < 0.001), high-sensitivity troponin T (r = 0.39, P < 0.001), and skin autofluorescence (marker of advanced glycation end products in tissues) (r = 0.41, P < 0.001). Multiple regression analyses demonstrated that when the API was used as a subordinate factor, these biomarkers were independent variables. According to the receiver operating characteristic curve analysis, an API of > 26 is the optimal cut-off point for determining albuminuria as ≥ 30 mg/g Cr, high high-sensitivity cardiac troponin T concentration as ≥ 0.014 ng/mL, or high skin autofluorescence as ≥ 3.0 arbitrary unit (area under the curve = 0.703, 0.702, and 0.704; and P < 0.001, respectively).

Conclusion: This investigation demonstrates that API had an independent relationship with relevant CVD biomarkers, such as urinary albumin, high-sensitivity troponin T, and skin autofluorescence. Additionally, the outcomes of receiver operating characteristic curve analysis are presented as values that an API > 26 defines for these biomarkers linked with the formation of CVD.

Keywords: Arterial pressure-volume index; Arterial stiffness; Biomarker; High-sensitivity cardiac troponin T; Hypertension; Skin autofluorescence; Urinary albumin.

Figure 1

Distribution of API. The API shows a nearly normal distribution, with a mean value of 27 (range: 16 - 42). API: arterial pressure-volume index.

Figure 2

Comparisons of API in patients with CCB and/or RAS inhibitor, showing the comparison of the API in the three groups (CCB alone (n = 66); RAS inhibitor alone (n = 62); combination of CCB and RAS inhibitors (n = 91)). The API was similar between the CCB alone (API: 27 ± 5) and RAS inhibitor alone (API: 28 ± 5) groups. However, patients receiving treatment with a combination of CCB and RAS inhibitors (API: 25 ± 4) had a significantly lower API than those treated with CCB or RAS inhibitors alone. The bars show standard deviation. *P = 0.003 vs. CCB. **P < 0.001 vs. RAS-i. ^#P = 0.047 vs. CCB, ^##P = 0.009 vs. RAS-i. API: arterial pressure-volume index; CCB: calcium channel blocker; RAS-i: renin angiotensin system inhibitor; SBP: systolic blood pressure.

Figure 3

Receiver-operating characteristic curve analysis. The detection of albuminuria (≥ 30 mg/g Cr) (a), high hs-cTnT concentration (≥ 0.014 ng/mL) (b), or high skin AF (≥ 3.0 arbitrary unit) (c) were determined by previous reports. The maximum Youden’s index indicated that an API of >26 was the optimal cut-off point for the determination of albuminuria (AUC = 0.703, P < 0.001), high hs-cTnT concentration (AUC = 0.702, P < 0.001), or high skin AF (AUC = 0.704, P < 0.001). API: arterial pressure-volume index; hs-cTnT: high-sensitivity cardiac troponin T; AF: autofluorescence; AUC area under the curve.