Negative association between plasma aldosterone concentration/plasma renin activity and morning blood pressure surge in never-treated hypertensive patients.

Morning blood pressure (BP) surge (MS) has been known to be a predictor of cardiovascular events. Currently, few studies have evaluated the underlying mechanism underlying MS, which may include neurohormonal factors and the renin-angiotensin-aldosterone system (RAAS). This study aimed to examine plasma aldosterone concentration (PAC) and plasma renin activity (PRA) and BP parameters with or without MS in never-treated subjects with essential hypertension. This cross-sectional study included a total of 261 patients (mean age: 48.8 years; 60.5% male) with never-treated essential hypertension who were registered in a working group at The Catholic University of Korea. The patients were divided into the MS group, which was defined as having the highest quartile of morning BP increase from sleep (>31 mmHg; n = 66) and the non-MS group (≤31 mmHg; n = 195). We collected 24-h ambulatory BP, pulse wave velocity, ankle brachial index, PAC and PRA from all patients. The measured PAC and PRA were lower in the MS group than in the non-MS group (PAC: 9.0 ± 5.4 ng/dl versus 12.2 ± 8.7 ng/dl, p < 0.001; PRA: 1.7 ± 1.3 ng/ml/h versus 2.6 ± 3.6 ng/ml/h, p = 0.002). The MS group had greater variations in daytime, nighttime and 24-h systolic blood pressure (SBPs) than the non-MS group (24-h SBP: 15.6 ± 4.4 mm Hg for the non-MS group and 18.9 ± 4.9 mmHg for the MS group; p < 0.001 for each). It is generally accepted that the sympathetic nervous system plays a major role in the regulation of BP variability. Therefore, further studies on sympathetic nervous system activation in hypertensives with extreme MS are needed. MS in enrolled patients who were at relatively low risk in this study may be less affected by the RAAS.

Association of prediabetes with impaired left atrial contractility in patients with never-treated hypertension.

AIM: Prediabetes defined by HbA1c 5.7-6.4 has been shown to be associated with left ventricular (LV) hypertrophy and diastolic dysfunction in hypertensive patients. We hypothesized HbA1c prediabetes may be related to the alterations of LA contractility or volume in nondiabetic hypertension. METHODS: Nondiabetic individuals on sinus rhythm were enrolled; 107 patients with never-treated hypertension, 134 patients with treated hypertension, and 71 normotensive subjects. Participants were classified as normal glucose tolerance (NGT, HbA1c<5.7), prediabetes (HbA1c 5.7-6.4) according to the ADA criteria. They underwent echocardiography to measure left atrial (LA) phasic volumes and functions, as well as mitral E/e' and mitral e'. RESULTS: In nondiabetic patients with never-treated hypertension, prediabetes saw lower LA total emptying fraction (53.7 ±â€¯8.2 vs. 48.3 ±â€¯9.9*) and mitral e' (7.38 ±â€¯2.18 vs. 6.17 ±â€¯1.50*) than NGT, implicating that the association of prediabetes with reduced LA contractility and LV stiffness. On the other hand, in nondiabetic patients with treated hypertension, prediabetes saw higher maximum LA volume/BSA (29.7 ±â€¯7.1 vs. 32.9 ±â€¯6.2* ml/mm2) and mitral E/e' (10.72 ±â€¯3.08 vs. 12.37 ±â€¯3.35*) than NGT, suggesting the relationship of prediabetes with increased LA preload. CONCLUSION: Prediabetes may be involved in the progression of LA structural and functional alterations in nondiabetic hypertensive patients.