Clinical hypertension: Blood pressure variability

[Mechanisms for the Development of Blood Pressure Variability and the Potential of Antihypertensive Drugs in Their Correction]

Blood pressure variability (BPV) is the fluctuations of blood pressure over a certain period of time under the influence of various factors. The issue of increased BPV is of particular clinical importance due to high predictive value of this parameter as a risk factor for fatal and non-fatal cardiovascular, cerebrovascular and renal events. It is proved that in the BPV increasing, the key role is played by impairments in arterial baroreflexes, which, in turn, are mediated by increased vascular stiffness, impact of angiotensin II and the sympathetic nervous system, endothelial dysfunction, nitric oxide deficiency and aging, including the vascular aging. Antihypertensive drugs that targeting largest amount of pathophysiological mechanisms in BPV increasing have a most advantages in correcting excessive pressure fluctuations. In this regard such drugs are perindopril and amlodipine, which can eliminate almost the entire spectrum of increased BPV causes and, therefore, optimally reduce the cardiovascular risk.

Blood Pressure Variability and Therapeutic Implications in Hypertension and Cardiovascular Diseases

Blood pressure (BP) is characterized by continuous dynamic and spontaneous oscillations occurring over lifetime and defining the so-called blood pressure variability (BPV). BPV has been associated with target organ damage, cardiovascular (CV) risk and death, suggesting the use of BPV as a new target in hypertension management in addition to mean BP values lowering. The purpose of the review is to focus on the therapeutic implications of BPV and summarize the effects of different drug classes on various types of BPV. Despite most first-line antihypertensive medications contribute to reduce both short and long term BPV, calcium channel blockers (CCBs) as monotherapy or fixed-combination therapy appear to be the most effective on BPV control. Further randomized interventional trials are needed to investigate which drug combinations are most appropriate according to patient CV risk stratification, in order to improve their CV outcomes.

Tighter Blood Pressure Control Is Associated with Lower Incidence of Erectile Dysfunction in Hypertensive Men

INTRODUCTION

Tighter blood pressure control is widely thought to be associated with better erectile function, although the preponderance of data is limited to dichotomous representations of hypertension without an attempt to look at degree of blood pressure control.

AIM

To determine the association between optimal blood pressure control over time and the development of erectile dysfunction (ED) in a cohort of potent men.

METHODS

We performed a retrospective cohort study of newly diagnosed hypertensive men without major medical comorbidities in an integrated healthcare system. Patients were stratified by exposure to hypertension, with varying levels of blood pressure control, as measured by ordinal categories of systolic blood pressure and deviation from the mean systolic pressure.

MAIN OUTCOME MEASURES

Incidence of ED was defined by at least 2 primary care or urology diagnoses of ED in our electronic health records within 2 years, at least 2 filled prescriptions for ED medications within 2 years, or 1 diagnosis of ED and 2 filled prescriptions for ED medications.

RESULTS

We identified 39,320 newly diagnosed hypertensive men. The overall incidence for ED was 13.9%, with a mean follow-up of 55.1 ± 28.7 months. Higher average systolic blood pressure was associated with a higher risk of ED in a dose-dependent manner (trend test, P < .001). Wide variation in blood pressure control was associated with a higher incidence of ED (OR [95% CI]; 1.359 [1.258-1.469]) and a shorter time to the development of ED (log rank, P < .0001).

CLINICAL IMPLICATIONS

We believe these data may serve as a motivator for hypertensive men to better adhere to their hypertension treatment regimen.

STRENGTH & LIMITATIONS

The retrospective nature of our study precludes us from drawing more than an association between tighter blood pressure control and ED. Strengths of our study include the large sample size, community cohort, and completeness of follow-up.

CONCLUSION

Among adults diagnosed with hypertension, tighter blood pressure control, as measured by average systolic blood pressure and deviation from the average, is associated with a lower incidence and a longer time to the development of ED. Hsiao W, Bertsch RA, Hung Y-Y, et al. Tighter Blood Pressure Control Is Associated with Lower Incidence of Erectile Dysfunction in Hypertensive Men. J Sex Med 2019;16:410-417.

Dynamic cerebral autoregulation measurement using rapid changes in head positioning: experiences in acute ischemic stroke and healthy control populations

The ideal technique for dynamic cerebral autoregulation (dCA) assessment in critically ill patients should provide considerable variability in blood pressure (BP) but without the need for patient cooperation. We proposed using rapid head positioning (RHP) over spontaneous BP fluctuations for dCA assessment in patients with acute ischemic stroke (AIS). Cerebral blood velocity (transcranial Doppler), beat-to-beat BP (Finometer), and end-tidal CO2 (capnography) were recorded during 5-min baseline and RHP in 16 controls (8 women and 8 men, mean age: 57 ± 16 yr) and 15 patients with AIS (7 women and 8 men, mean age: 69 ± 8 yr) at two (12 ± 8 days) and three visits (13.3 ± 6.9 h, 4.8 ± 3.2 days, and 93.9 ± 11.5 days from the symptom onset), respectively. All participants were able to complete the RHP protocol without difficulty. Compared with controls, patients with AIS were hypocapnic (all visits, P < 0.0024) and hypertensive ( visit 1, P = 0.011), although BP gradually reduced after the acute phase. RHP demonstrated greater beat-to-beat BP variability (BPV) in controls ( visits 1 and 2, P < 0.001) but not in patients with AIS at any visit. Compared with controls, a reduced autoregulation index (ARI) was demonstrated in patients with AIS, at visit 2 for the baseline recording but not at other visits or during RHP. The area under the receiver-operating curve was 0.53 and 0.54 for baseline and RHP, respectively. The RHP paradigm required minimal patient cooperation and could be considered a feasible alternative for assessing dCA, mainly in conditions leading to increased BPV. The lack of BPV increase in AIS with RHP deserves further investigation.

NEW & NOTEWORTHY This study used rapid head positioning (RHP) to enhance blood pressure (BP) variability (BPV) to improve BP signal-to-noise ratio and reliability of dynamic cerebral autoregulation (dCA). RHP was well accepted by controls and acute ischemic stroke (AIS); the increased BPV induced in controls was not observed in AIS, suggesting BPV at rest was already elevated. RHP did not improve detection of impaired CA in AIS; further work is needed to understand the different responses observed.