Greater Mean Blood Pressure Research Articles

Abstract P181: Optimizing Precision of Hypertension Care to Maximize Blood Pressure Control (OPTI-BP): A Pilot Study Utilizing a Smartphone App

Background: About half of patients with hypertension (HTN) respond to any given antihypertensive drug. Discordance in pathophysiologic pathways underlying HTN and anti-HTN mechanism of action are major contributors. Personalizing anti-HTN therapy could optimize blood pressure (BP) control. The objective of OPTI-BP was to assess the pragmatic implementation of a smartphone app used to guide physiologically optimal HTN treatment based on plasma renin activity (PRA). Methods: The smartphone app (PRA-HTN) and PRA testing was implemented in three primary care clinics. Patients with untreated or treated but uncontrolled HTN, aged 18-65 years, were recruited. BP and PRA were measured at baseline (and again as often as needed) with final BP measured at 6 months. PRA level and current anti-HTN meds are entered into the app and recommendations to optimize volume- and RAS blocking meds returned. Providers were at liberty to follow or disregard app recommendations. The primary outcome was BP change from baseline to 6 months. Independent t-test was used to compare BP responses of patients whose clinicians followed the app recommendations vs. those who did not. A multivariable linear regression analysis adjusting for baseline BP, age and sex was also conducted. Results: This analysis includes 29 white patients, including 11 (37.9%) women, with a mean age of 52 ± 9 years and a median baseline PRA of 1.3 ng/mL/hr (IQR 0.5-3.1 ng/mL/hr). Mean baseline BP between patients whose clinicians followed the app recommendations (n=16, 55%) vs. those who did not (n=13, 45%) was not statistically different ( P >0.05). After 6 months, the average BP change among patients whose clinicians followed the app recommendations was -14 ± 20/-7 ± 9 mmHg vs. -5 ± 21/-2 ± 9 mmHg among those who did not. In regression analysis, use of app recommended therapy was associated with greater mean BP difference of -13±8/-9±4 mmHg ( P =0.1/0.02). Conclusion: This pilot study demonstrates that PRA testing and implementation of recommendations from a smartphone app that utilizes PRA to optimize anti-HTN therapy was associated with good BP lowering among a relatively small cohort of patients. Future studies using larger sample sizes are warranted to confirm these preliminary findings.

Abstract TMP103: A Culturally-tailored, Skills-based Intervention to Reduce Vascular Risk in a Multi-ethnic Group of Mild/Moderate Stroke Survivors: An Interim Analysis from the DESERVE Trial

Introduction: Secondary stroke prevention strategies have proven suboptimal in underserved communities and minority populations. Methods: The Discharge Educational Strategies for Reduction of Vascular Events (DESERVE) trial tested the efficacy of an innovative skills-based intervention focused on risk perception, medication adherence, and patient-physician communication (vs. usual care enhanced with educational material [EUC]) on blood pressure (BP) reduction among mild/moderate stroke (NIH Stroke Scale ≤ 15) or TIA patients at 1 year post discharge. Study participants were stratified by interview language (English/Spanish) and randomized to intervention or EUC. BP reduction was the difference between systolic BP at baseline and 1-year post-discharge. We assessed differences in baseline characteristics and mean BP reduction between trial arms, overall and by race/ethnicity. Linear regressions evaluated mean difference in blood pressure reduction between trial arms, adjusting for characteristics that differed between trial arms at baseline and language of interview. Results: To date, 290 of 552 stroke/TIA patients recruited at baseline (25% white, 32% black, 36% Hispanic) were evaluated at 1 year (n=145 in each arm). Overall, there was a trend toward greater mean BP reduction in the intervention vs. EUC group (9.3 vs. 6.0 mmHg, p=0.259). Mean BP reduction was significantly greater in the intervention vs. EUC group among Hispanics (9.9 vs. -0.7 mmHg, p=0.040). Among Hispanics, after adjusting for interview language, sex, and place of birth, mean BP reduction was 10.9 mmHg greater in the intervention vs. EUC group (p=0.041). Mean BP reduction did not differ significantly between trial arms among non-Hispanics. We are currently gathering information to evaluate the impact of the intervention on secondary stroke incidence. Conclusions: Few behavioral intervention studies in stroke survivors have reported significant differences in vascular risk reduction in the longer term, and fewer have focused on a skills-based approach. Culturally-tailored, skills-based interventions may be more useful than knowledge-focused interventions in achieving sustained vascular risk reduction and addressing race/ethnic disparities in stroke.

Ten-year longitudinal change in aortic stiffness assessed by cardiac MRI in the second half of the human lifespan: the multi-ethnic study of atherosclerosis.

Longitudinal determinants of aortic stiffness (AS) measured by magnetic resonance imaging (MRI) have not been assessed in a large community-based population. Our aim was to examine the determinants of change in thoracic AS over 10 years of follow-up in a multi-ethnic population of individuals 45 years of age and older measured by MRI. We studied 1160 participants (mean age = 60 ± 9 years at baseline, 45% male) with aortic MRI at both the MESA Year 0 and Year 10 examinations. Ascending and descending aorta distensibility (AAD/DAD) and aortic arch pulse-wave velocity (PWV) were measured using MRI. Determinants of the change in AS parameters over 10 years were assessed using linear regression adjusted for baseline values, demographic variables, baseline risk factors and change in risk factors, and chronic risk exposure. AAD and DAD decreased slightly (5% decrease in median for AAD: 1.33-1.26 mmHg(-1) · 10(-3), P = 0.008; 5% decrease in median for DAD: 1.73-1.64 mmHg(-1) · 10(-3), P < 0.001), and PWV increased over 10 years (18% increase in median: 6.8-8.0 m/s P < 0.001). Baseline age was related to a reduction in AAD and DAD and an increase in PWV throughout the follow-up period. Baseline and change in mean blood pressure and continued smoking were associated with a reduction in AAD and an increase in PWV. Furthermore, baseline heart rate was also related to a reduction in AAD and DAD. Blood pressure normalization was related to less aortic stiffening throughout the follow-up period. In our longitudinal, community-based cohort study of adult individuals aged 45 years or greater, greater mean blood pressure and a history of smoking history were associated with increased aortic stiffening over 10 years as assessed by MRI.

Effects of intravenous azimilide on cardiac performance, fibrillation threshold, and hemodynamics in anesthetized dogs.

The class III antiarrhythmic azimilide (E-1-[[[5-(4-chlorophenyl)-2-furanyl]methylene]-amino]-3-[4-(4-methyl-1- piperazinyl)butyl]-2,4-imidazolidinedione dihydrochloride; WHO No. 7299, CAS 149888-94-8), by slow infusion or stepwise bolus doses, was evaluated for effects on heart rate, blood pressure, and cardiac pump function, excitability, and refractoriness in anesthetized dogs. Infusion (0.6 mg/kg/min) in male beagles (n = 5) to a maximum dose of 54 mg/kg increased QTc more than 20 ms at 2.0 mg/kg. At a dose of 8.9 mg/kg i.v., QTc increased 34% above baseline and remained elevated throughout the subsequent infusion and for at least 60 min postinfusion. At this maximum class III dose, azimilide increased heart contractile force (HCF) 10% and +dP/dt 34% and decreased heart rate (HR) 12%, without significantly changing mean blood pressure (MBP), left ventricular end diastolic pressure, -dP/dt, stroke volume (SV), or cardiac output (CO). At the mean maximum 47 mg/kg i.v. dose, QTc remained elevated, but decreases were observed in HCF (-27%), +dP/dt (-24%), -dP/dt (-35%), SV (-16%), and CO (-52%). Cumulative intravenous bolus injections of azimilide (0.3, 1, 3, 10, and 30 mg/kg) in male mongrels (n = 5) increased effective refractory period (ERP) and +dP/dt (18% and 16%, respectively, at 10 mg/kg) as a function of dose and significantly decreased HR (-22% at 10 mg/kg). MBP decreased significantly (-23%) only at the highest dose. Ventricular fibrillation threshold (VFT) was unchanged at 30 mg/kg. Effects of dl- (n = 3) and d-sotalol (n = 4) on ERP and HR were similar to azimilide's, but both compounds caused a greater MBP depression and VFT elevation. These results suggest that azimilide is well tolerated by the cardiovascular system, providing an increase in contractility and a slight decrease in HR at intravenous doses that produced a large or maximum increase in cardiac refractoriness.

Chronic proteinuric nephropathies: Outcomes and response to treatment in a prospective cohort of 352 patients with different patterns of renal injury

The Ramipril Efficacy in Nephropathy (REIN) study found that angiotensin-converting enzyme (ACE) inhibitors effectively decreased proteinuria, glomerular filtration rate (GFR) decline (ΔGFR), and incidence of end-stage renal disease (ESRD) in patients with proteinuric chronic nephropathies. In this study, we prospectively investigated the main clinical determinants of progression and response to treatment in the 352 patients enrolled into the REIN study. Mean ΔGFR (0.56 ± 0.05 [SEM] versus 0.21 ± 0.05 mL/min/1.73 m2/mo; P = 0.0001) and incidence of ESRD (30% and 10%; P = 0.0001) were more than twice that in patients with proteinuria of 2 g/24 h or greater of protein compared with those with protein less than 2 g/24 h (relative risk [RR], 4.07; 95% confidence interval [CI], 2.20 to 7.52), as well as in patients with hypertension compared with normotension (mean ΔGFR, 0.48 ± 0.05 versus 0.22 ± 0.05 mL/min/1.73 m2/mon; P = 0.0006; ESRD, 25% versus 10%; P = 0.004; RR, 3.18; 95% CI, 1.38 to 7.32). Hypertension at study entry (P = 0.038), greater mean blood pressure on follow-up (P = 0.002), and urinary protein excretion rate (P = 0.0001) were independent predictors of faster ΔGFR. ΔGFR was approximately twofold faster in patients with type 2 diabetes than in those with primary glomerular disease (P = 0.002; including immunoglobulin A [IgA] nephropathy, P = 0.009); nephrosclerosis (P = 0.03), adult polycystic kidney disease (APKD), or chronic interstitial nephritis (P = 0.006). Diabetes at study entry (P = 0.02) and greater mean blood pressure (P = 0.0001) and urinary protein excretion rate (P = 0.0001) on follow-up were independent predictors of faster ΔGFR. After correction for baseline covariates, diabetes was also associated with an increased risk for progression to ESRD (RR, 2.39; 95% CI, 1.01 to 5.68; P < 0.05). At multivariate analyses, ramipril significantly decreased ΔGFR (regression coefficient,−0.23 ± 0.11 [SEM]; P = 0.036) and ESRD (RR, 2.08; 95% CI, 1.21 to 3.57; P = 0.008) in patients with baseline proteinuria of 2 g/24 h or greater of protein, and the renoprotective effect increased for increasing levels of proteinuria. Ramipril decreased ΔGFR to a similar extent in normotensive and hypertensive patients (–0.14 ± 0.11 versus –0.14 ± 0.09) and significantly limited ESRD in hypertensive patients (RR, 2.03; 95% CI, 1.26 to 3.26; P = 0.004). ΔGFR was decreased by 42% in primary glomerular disease (P = 0.017), by 35% in IgA nephropathy, and by 37% in nephrosclerosis, but was not improved in type 2 diabetes, APKD, or interstitial nephritis. At multivariate analyses, ramipril significantly slowed ΔGFR (–0.24 ±0.08; P = 0.004) and progression to ESRD (RR, 2.32; 95% CI, 1.36 to 3.96; P = 0.002) in patients without diabetes, but not in patients with diabetes, who tended to have a faster ΔGFR (+0.62 ± 0.44) on ramipril therapy. In summary, patients with proteinuria of 2 g/24 h or greater of protein, preexisting hypertension, or type 2 diabetes were faster progressors. Greater blood pressure and degree of proteinuria were the strongest determinants of faster GFR decline. The renoprotective effect of ramipril was similar in patients with normotension and hypertension. Hypertensive patients and those with proteinuria of 2 g/24 h or greater of protein, primary glomerular disease, or nephrosclerosis gained the most from ACE inhibitor treatment. During the study period, those with proteinuria less than 2 g/24 h of protein, type 2 diabetes, or polycystic kidney disease did not benefit by treatment to an appreciable extent.

Observations on some possible precursors of essential hypertension and coronary artery disease: VII. The subjective reaction to the cold pressor test as expressed in the verbal response

1. 1. The study population consisted of 712 white male medical students who took a standardized cold pressor test. 2. 2. The relationship between the degree of circulatory reactivity and the character of the subjective verbal response to an ice water stimulus has been investigated. 3. 3. Verbal response groups expressing pain and very disturbed feelings have somewhat greater mean blood pressure and heart rate increases to a standard cold stimulus than groups who indicate cold or minor undisturbing sensations. The differences, although statistically significant, are never large, and when the ceiling effect is taken into account most of these small differences between verbal response groups are minimized.