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In patients with chronic kidney disease, serum potassium level is a factor influencing sudden cardiac death (SCD). The aim of our analysis was to study the combined effect of serum potassium level and renal function on the onset of SCD in elderly hypertensive subjects. Data from the 3620 hypertensive patients aged over 70 years were extracted from three randomized clinical trials included in the INDANA database. During a mean follow up of 4.5 years, 81 patients (2.24%) died from SCD. Mean serum potassium levels and prevalence of chronic kidney disease were not different in patients who died from SCD. In addition to serum potassium and creatinine levels, 14 clinical and biological variables linked to cardiovascular diseases recorded at baseline were analyzed using a Bayesian network. The area under the receiver operating characteristic curve of the Bayesian model reached 0.91. Bayesian inference was used to simulate the combined effects of serum potassium and creatinine levels on SCD. Our analysis, using simulated data from Bayesian model, showed that the estimated probabilities of SCD was significantly increased in case of hyperkalemia (>5.0 mmol/l) and in case of hypokalemia (

The diameters of the retinal microvasculature reflect intermediate target organ damage and predict adverse health outcomes. In view of the pulsatility of the cerebral blood flow and refinement of software used for off-line analysis, we assessed the repeatability of retinal microvascular diameters in ECG-gated vs. non-gated images using nonmydriatic retinal photographs (Canon Cr-DGi visualization system) postprocessed by IVAN (Vasculomatic ala Nicola, version 1.1) or SIVA (Singapore I Vessel Assessment, version 3.6). Using these algorithms, we determined the central retinal arteriolar (CRAE) and venular (CRVE) equivalents and their ratio (arteriole-to-venule ratio (AVR)). The estimates of CRAE (mean, 158.5 μm), CRVE (222.5 μm) and AVR (0.71) in 10 volunteers were unaffected (P⩾0.059) by ECG gating. We assessed intragrader repeatability by the Bland and Altman approach in 30 participants with non-gated images and 30 with ECG-gated photographs. Repeatability, which was expressed as the percentage of near maximal variability (4-s.d. range), did not improve with ECG gating. Using SIVA, CRAE and CRVE were systematically larger (P⩽0.031), and the AVR estimates were similar (P⩾0.15) compared with IVAN. The differences (IVAN-SIVA) averaged -5.4 μm for CRAE, -3.9 μm for CRVE and -0.012 for AVR in the non-gated images and -3.3 μm, -6.9 μm and 0.006, respectively, in the ECG-gated photographs. In conclusion, ECG gating does not affect estimates of the retinal microvascular diameters or improve intragrader repeatability. SIVA yields slightly but significantly larger estimates of the retinal arteriolar and venular diameters. Combining historical readings analyzed by IVAN with more recent readings by SIVA is possible only for AVR and is not recommended for either CRAE or CRVE. ispartof: Hypertension Research vol:39 issue:12 pages:886-892 ispartof: location:England status: published

Retinal arteriolar narrowing and high pulse pressure (PP) are associated with macrovascular complications and microvascular renal disease. Few studies addressed whether in seniors (⩾60 years) estimated glomerular filtration rate (eGFR) is independently related to central retinal arteriolar equivalent (CRAE) and PP. In 292 randomly recruited seniors (49.3% women; mean, 68.2 years), we measured PP by standard sphygmomanometry, CRAE (IVAN software), eGFR (Chronic Kidney Disease Epidemiology Collaboration equation) and stage of chronic kidney disease (CKD (Kidney Disease Outcomes Quality Initiative guideline)). Statistical methods included linear and logistic regression. PP, CRAE and eGFR averaged 59.2 mm Hg, 146.3 μm and 79.9 ml min(-1) per 1.73 m(2). Decline in eGFR (-2.27 ml min(-1) per 1.73 m(2) per 15 μm; P=0.011) occurred in parallel with CRAE narrowing. CRAE (effect size per 1-s.d. increment, -1.85 μm; P=0.032) and eGFR (-2.68 ml min(-1) per 1.73 m(2); P=0.003) both declined with higher PP. With PP increasing from 63 to 73 mm Hg (threshold for macrovascular complications), CRAE dropped by -4.70 μm (P⩽0.037). A 70-mm Hg PP threshold corresponded with a 150-μm CRAE cutoff. The risk of CKD (stage ⩾2 vs. 1; n=203 vs. 89) rose with CRAE

The absence of an outcome-driven reference frame for self-measured pulse pressure (PP) limits its clinical applicability. In an attempt to derive an operational threshold for self-measured PP, we analyzed 6470 participants (mean age 59.3 years; 56.9% women; 22.5% on antihypertensive treatment) from 5 general population cohorts included in the International Database on HOme blood pressure in relation to Cardiovascular Outcome. During 8.3 years of follow-up (median), 294 cardiovascular deaths, 393 strokes and 336 cardiac events occurred. In 3285 younger subjects (

Hypertension guidelines recommend blood pressure self-measurement at home (HBP), but no previous trial has assessed cardiovascular outcomes in hypertensive patients treated according to HBP. The multicenter Hypertension Objective Treatment Based on Measurement by Electrical Devices of Blood Pressure (HOMED-BP; 2001-2010) trial involved 3518 patients (50% women; mean age 59.6 years) with an untreated systolic/diastolic HBP of 135-179/85-119 mm Hg. In a 2 × 3 design, patients were randomized to usual control (125-134/80-84 mm Hg (UC)) vs. tight control (

We assessed the feasibility of ambulatory pulse wave analysis by comparing this approach with an established tonometric technique. We investigated 35 volunteers (45.6 years; 51.0% women) exclusively at rest (R study) and 83 volunteers (49.9 years; 61.4% women) at rest and during daytime (1000-2000 h) ambulatory monitoring (R+A study). We recorded central systolic (cSP), diastolic (cDP) and pulse (cPP) pressures, augmentation index (cAI) and pulse wave velocity (PWV) by brachial oscillometry (Mobil-O-Graph 24h PWA Monitor) and radial tonometry (SphygmoCor). We applied the Bland and Altman's statistics. In the R study, tonometric and oscillometric estimates of cSP (105.6 vs. 106.9 mm Hg), cDP (74.6 vs. 74.7 mm Hg), cPP (31.0 vs. 32.1 mm Hg), cAI (21.1 vs. 20.6%) and PWV (7.3 vs. 7.0 m s(-1)) were similar (P0.11). In the R+A study, tonometric vs. oscillometric assessment yielded similar values for cSP (115.4 vs. 113.9 mm Hg; P=0.19) and cAI (26.5 vs. 25.3%; P=0.54), but lower cDP (77.8 vs. 81.9 mm Hg; P

It remains unknown whether diabetes and high blood pressure (BP) are simply additive risk factors for cardiovascular outcome or whether they act synergistically and potentiate one another. We performed 24-h ambulatory BP monitoring in 8494 subjects (mean age, 54.6 years; 47.0% women; 6.9% diabetic patients) enrolled in prospective population studies in 10 countries. In multivariable-adjusted Cox regression, we assessed the additive as opposed to the synergistic effects of BP and diabetes in relation to a composite cardiovascular endpoint by testing the significance of appropriate interaction terms. During 10.6 years (median follow-up), 1066 participants had a cardiovascular complication. Diabetes mellitus as well as the 24-h ambulatory BP were independent and powerful predictors of the composite cardiovascular endpoint. However, there was no synergistic interaction between diabetes and 24-h, daytime, or nighttime, systolic or diastolic ambulatory BP (P for interaction, 0.07P0.97). The only exception was a borderline synergistic effect between diabetes and daytime diastolic BP in relation to the composite cardiovascular endpoint (P=0.04). In diabetic patients, with normotension as the reference group, the adjusted hazard ratios for the cardiovascular endpoint were 1.35 (95% confidence interval (CI), 0.87-2.11) for white-coat hypertension, 1.78 (95% CI, 1.22-2.60) for masked hypertension and 2.44 (95% CI, 1.92-3.11) for sustained hypertension. The hazard ratios for non-diabetic subjects were not different from those of diabetic patients (P-values for interaction, 0.09P0.72). In conclusion, in a large international population-based database, both diabetes mellitus and BP contributed equally to the risk of cardiovascular complications without evidence for a synergistic effect.Hypertension Research advance online publication, 10 February 2011; doi:10.1038/hr.2011.6. ispartof: Hypertension research : official journal of the Japanese Society of Hypertension vol:34 issue:6 pages:714-721 ispartof: location:England status: published

Ambulatory blood pressure (BP) monitoring provides information not only on the BP level but also on the diurnal changes in BP. In the present review, we summarized the main findings of the International Database on Ambulatory BP in relation to Cardiovascular Outcome (IDACO) with regard to risk stratification based on BP variability. The predictive accuracy of daytime and nighttime BP and the night-to-day BP ratio depended on the disease outcome under study and treatment status, and differed for fatal outcomes compared with the composite of fatal and nonfatal diseases. An exaggerated morning surge, exceeding the 90th percentile of the population, is an independent risk factor for mortality and cardiovascular and cardiac events. Conversely, a sleep-trough or preawakening morning surge in systolic BP below 20 mm Hg is probably not associated with an increased risk of death or cardiovascular events. BP variability as captured by the average of the daytime and nighttime s.d. weighted for the duration of the daytime and nighttime interval (s.d.(dn)) and the average real variability (ARV(24)) predicted the outcome, but improved the prediction of the composite of all cardiovascular events by only 0.1%. In conclusion, the IDACO observations support the concept that BP variability adds to risk stratification, but above all highlight that 24-h ambulatory BP level remains the main predictor to be considered in clinical practice. ispartof: Hypertension Research vol:33 issue:8 pages:757-766 ispartof: location:England status: published

We assessed, in a double-blind, placebo-controlled trial, whether lowering blood pressure (BP) prevents the recurrence of stroke in Chinese patients with cerebrovascular disease. Patients were randomized into two groups: 2825 patients received a placebo and 2840 patients received 2.5 mg of indapamide daily. The primary and secondary outcomes were the recurrence of fatal or nonfatal stroke and major fatal and nonfatal cardiovascular events, respectively. The average systolic/diastolic BP at randomization was 153.8/92.8 mm Hg. At median follow-up (2 years), BP was, on an average, 6.8/3.3 mm Hg lower in patients on active treatment. In total, 143 patients on indapamide and 219 patients on placebo had recurrent strokes (hazard ratio for indapamide, 0.69; 95% confidence interval (CI): 0.54-0.89; P