Blood Pressure Variability and Risk of New-Onset Atrial Fibrillation

Abstract

Background and Purpose-Increased visit-to-visit variability in blood pressure (BP) is a powerful risk factor for stroke, but the mechanism is uncertain. We hypothesized that BP variability might affect the risk of new atrial fibrillation (AF). Methods-We did a systematic review of large randomized controlled trials reporting new-onset AF by treatment allocation, excluding studies in heart failure and acute myocardial infarction. Estimates of the risk of new AF by treatment allocation were related to effects of treatment on group variability in BP. Results-Of 94 eligible randomized controlled trials, 14 reported rates of new AF. Although there was considerable heterogeneity between trials in effects of treatment on variance ratio (PϽ0.0001), lower variance ratio was unrelated to new-onset AF either on meta-analysis (ORϭ1.02; 95% CI 0.90 to 1.15; 125 878 patients; 13 comparisons) or on metaregression (log OR versus log variance ratio of systolic blood pressure r 2 ϭ0.109, Pϭ0.270). Angiotensin receptor blockers tended to reduce new-onset AF (OR 0.85; 95% CI 0.71 to 1.01; Pϭ0.067; 4 trials; 47 482 patients) with significant reductions in 2 individual trials but had no consistent reduction on variability in BP. Conclusions-Effects of randomized treatment on variability in BP are unrelated to risk of new-onset AF, suggesting that other mechanisms account for the link between variability and stroke risk. However, a lower incidence of AF in patients randomized to angiotensin receptor blockers may explain reductions in stroke risk in some trials.

Response of Day-to-Day Home Blood Pressure Variability by Antihypertensive Drug Class After Transient Ischemic Attack or Nondisabling Stroke

“…Although the 4% reduction in BP variability with low-variability agents seems small, this is significantly different to the 7.8% increase with high-variability agents and is likely to reflect greater reductions in some patients. This effect is consistent with the effect of CCBs and diuretics on visit-to-visit SBP variability and maximum SBP in large RCTs [1][2][3][4][5][6] and may explain the reduction in the subsequent risk of stroke, although an appropriate choice of antihypertensives also needs to consider other demographic factors such as ethnicity and comorbidities. Nonetheless, this study suggests that HBPM offers a potential practical method of monitoring the change in BP variability in response to antihypertensive treatment, with the potential to reduce BP variability-associated cardiovascular risk.…”

“…Calcium channel blockers (CCBs) and thiazide diuretics reduced maximum SBP and SBP variability in the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA) and Medical Research Council 2 (MRC-2) studies compared with renin-angiotensin system inhibitors (RASi) or β-blockers, 3 explaining differences in stroke risk between treatment groups, with similar effects in meta-analyses of all published studies. [4][5][6] Drug effects on SBP variability were seen in a wide range of patients 4 and persisted when used in combination. 7 However, clinical readings are impractical for prospectively assessing the effects of drug changes on SBP variability and maximum SBP, particularly in secondary prevention of acute cerebrovascular events when rapid control of BP variability may be desirable.…”

Atrial Fibrillation and Hypertension

“…A systematic review of 14 large randomized controlled trials reporting new-onset AF, excluding studies in heart failure and acute myocardial infarction, did not find any significant link between visit-to-visit BP variability and risk of new-onset AF. 54 However, detection of AF remains a problem and a possibility of silent AF contributing to strokes in people with high BP variability cannot be excluded.…”

Hypertension and atrial fibrillation: epidemiology, pathophysiology and therapeutic implications

“…Instability of BP may reflect increase arterial stiffness and surge of BP increases risk of stroke, although not directly related to newonset AF. 75 As a result, variability of BP has an important role in the progression of end-organ damage and cardiovascular events. 76 Studies are needed to define the optimal BP monitoring treatment target in patients with hypertension.…”