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Background: Evidence suggests marginal superiority of static aortic systolic blood pressure (aSBP) compared with brachial SBP (bSBP) regarding the association with organ damage and prognosis of cardiovascular disease (CVD). The noninvasive 24-hour aSBP assessment is feasible and associates better with presence of left ventricular hypertrophy compared with 24-hour bSBP. We aimed at comparing the association of 24-hour aSBP and 24-hour bSBP with indices of arterial damage and examining the role of 24-hour SBP amplification variability (within-subjects' SD) in this association., Methods: Consecutive subjects referred for CVD risk assessment underwent 24-hour aortic and brachial ambulatory BP monitoring using a validated oscillometric device (Mobil-O-Graph). Arterial damage was assessed by carotid intima-media thickness (IMT) and detection of carotid and femoral atheromatosis (plaque presence)., Results: Cross-sectionally 501 individuals (aged 54±13 years, 57% men, 80% hypertensives) were examined. Multivariable analysis revealed superiority of 24-hour aSBP regarding the association with IMT, carotid hypertrophy and carotid-but not femoral-atheromatosis. In receiver operator characteristics analysis, 24-hour aSBP displayed a higher discriminatory ability-compared to 24-hour bSBP-for the detection of both carotid hypertrophy (area under the curve, 0.662 versus 0.624, P <0.05) and carotid atheromatosis (area under the curve, 0.573 versus 0.547, P <0.05). This effect was more prominent in individuals with above-median 24-hour SD of SBP amplification., Conclusions: Our results suggest that 24-hour aSBP assessment may be of significant value in clinical practice to detect site-specific arterial damage on the basis of pressure amplification variability and should be prospectively examined in clinical trials.

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Observational studies have shown an association between hypertension and atrial fibrillation (AF). Aggressive blood pressure management in patients with known AF reduces overall arrhythmia burden, but it remains unclear whether hypertension is causative for AF. To address this question, this study explored the relationship between genetic predictors of blood pressure and risk of AF. We secondarily explored the relationship between genetically proxied use of antihypertensive drugs and risk of AF. Two-sample Mendelian randomization was performed using an inverse-variance weighted meta-analysis with weighted median Mendelian randomization and Egger intercept tests performed as sensitivity analyses. Summary statistics for systolic blood pressure, diastolic blood pressure, and pulse pressure were obtained from the International Consortium of Blood Pressure and the UK Biobank discovery analysis and AF from the 2018 Atrial Fibrillation Genetics Consortium multiethnic genome-wide association studies. Increases in genetically proxied systolic blood pressure, diastolic blood pressure, or pulse pressure by 10 mm Hg were associated with increased odds of AF (systolic blood pressure: odds ratio [OR], 1.17 [95% CI, 1.11-1.22]; P =1×10 -11 ; diastolic blood pressure: OR, 1.25 [95% CI, 1.16-1.35]; P =3×10 -8 ; pulse pressure: OR, 1.1 [95% CI, 1.0-1.2]; P =0.05). Decreases in systolic blood pressure by 10 mm Hg estimated by genetic proxies of antihypertensive medications showed calcium channel blockers (OR, 0.66 [95% CI, 0.57-0.76]; P =8×10 -9 ) and β-blockers (OR, 0.61 [95% CI, 0.46-0.81]; P =6×10 -4 ) decreased the risk of AF. Blood pressure-increasing genetic variants were associated with increased risk of AF, consistent with a causal relationship between blood pressure and AF. These data support the concept that blood pressure reduction with calcium channel blockade or β-blockade could reduce the risk of AF.

Hypertension is the leading risk factor for stroke. Yet, it remains unknown whether blood pressure pulsatility (pulse pressure [PP]) causally affects stroke risk independently of the steady pressure component (mean arterial pressure [MAP]). It is further unknown how the effects of MAP and PP on stroke risk vary with age and stroke cause. Using data from UK Biobank (N=408 228; 38-71 years), we selected genetic variants as instruments for MAP and PP at age ≤55 and >55 years and across age deciles. We applied multivariable Mendelian randomization analyses to explore associations with ischemic stroke, intracerebral hemorrhage, and their subtypes. Higher genetically predicted MAP was associated with higher risk of ischemic stroke and intracerebral hemorrhage across the examined age spectrum. Independent of MAP, higher genetically predicted PP only at age >55 years was further associated with higher risk of ischemic stroke (odds ratio per-SD-increment, 1.23 [95% CI, 1.13-1.34]). Among subtypes, the effect of genetically predicted MAP on large artery stroke was attenuated, whereas the effect of genetically predicted PP was augmented with increasing age. Genetically predicted MAP, but not PP, was associated with small vessel stroke and deep intracerebral hemorrhage homogeneously across age deciles. Neither genetically predicted MAP nor PP were associated with lobar intracerebral hemorrhage. Beyond an effect of high MAP at any age on ischemic and hemorrhagic stroke, our results support an independent causal effect of high PP at older ages on large artery stroke. This finding warrants further investigation for the development of stroke preventive strategies targeting pulsatility in later life.

Background Elevated blood pressure is a major cause of cardiovascular morbidity and mortality. However, it is not known whether midlife blood pressure affects later life cardiovascular risk independent of later life blood pressure. Methods and Results Using genetic association estimates from the UK Biobank and CARDIoGRAMplusC4D consortium, univariable mendelian randomization was performed to investigate the total effect of genetically predicted mean arterial pressure (MAP) at age ≤55 years on coronary artery disease (CAD) risk, and multivariable mendelian randomization was performed to investigate the effect of genetically predicted MAP on CAD risk after adjusting for genetically predicted MAP at age >55 years. In both univariable and multivariable mendelian randomization analyses, there was consistent evidence of higher genetically predicted MAP at age ≤55 years increasing CAD risk. This association persisted after adjusting for genetically predicted MAP at age >55 years, when considering nonoverlapping populations for the derivation of MAP and CAD risk genetic association estimates, when investigating only incident CAD events after age >55 years, and when restricting the analysis to variants with most heterogeneity in their associations with MAP ≤55 and >55 years. For a 10-mm Hg increase in genetically predicted MAP at age ≤55 years, the odds ratio of later life CAD was 1.43 (95% CI, 1.16-1.77; P =0.001) after adjusting for genetically predicted MAP at age >55 years. Conclusions These mendelian randomization findings support a cumulative lifetime effect of elevated blood pressure on increasing CAD risk. Clinical and public health efforts toward cardiovascular disease reduction should optimize blood pressure control throughout life.

Objective: Ischemic stroke etiology remains undetermined in 30% of cases. We explored the genetic architecture of stroke classified as undetermined to test if mechanisms and risk factors underlying large‐artery atherosclerotic (LAAS), cardioembolic (CES), and small‐vessel stroke (SVS) contribute to its pathogenesis. Methods: We analyzed genome‐wide data from 16,851 ischemic stroke cases and 32,473 controls. Using polygenic risk scores for LAAS, CES, and SVS, we assessed the genetic overlap with stroke of undetermined source and used pairwise genomewide association study (GWAS‐PW) to search for shared loci. We then applied Mendelian randomization (MR) to identify potentially causal risk factors of stroke of undetermined source. Results: Genetic risk for LAS, CES, and SVS was associated with stroke of undetermined source pointing to overlap in their genetic architecture. Pairwise analyses revealed 19 shared loci with LAAS, 2 with CES, and 5 with SVS that have been implicated in atherosclerosis‐related phenotypes. Genetic liability to both carotid atherosclerosis and atrial fibrillation was associated with stroke of undetermined source, but the association with atrial fibrillation was attenuated after excluding cases with incomplete diagnostic workup. MR analyses showed effects of genetically determinants of blood pressure, diabetes, waist‐to‐hip ratio, inflammatory pathways (IL‐6 signaling, MCP‐1/CCL2 levels), and factor XI levels on stroke of undetermined source. Interpretation: Stroke of undetermined source shares genetic and vascular risk factors with other stroke subtypes, especially LAAS, thus highlighting the diagnostic limitations of current subtyping approaches. The potentially causal associations with carotid atherosclerosis and atherosclerotic risk factors might have implications for prevention strategies targeting these mechanisms. ANN NEUROL 2022;91:640–651 [ABSTRACT FROM AUTHOR]

Introduction: Midlife clustering of vascular risk factors has been associated with late‐life dementia, but causal effects of individual biological and lifestyle factors remain largely unknown. Methods: Among 229,976 individuals (mean follow‐up 9 years), we explored whether midlife cardiovascular health measured by Life's Simple 7 (LS7) is associated with incident all‐cause dementia and whether the individual components of the score are causally associated with dementia. Results: Adherence to the biological metrics of LS7 (blood pressure, cholesterol, glycemic status) was associated with lower incident dementia risk (hazard ratio = 0.93 per 1‐point increase, 95% confidence interval [CI; 0.89–0.96]). In contrast, there was no association between the composite LS7 score and the lifestyle subscore (smoking, body mass index, diet, physical activity) and incident dementia. In Mendelian randomization analyses, genetically elevated blood pressure was associated with higher risk of dementia (odds ratio = 1.31 per one‐standard deviation increase, 95% CI [1.05–1.60]). Discussion: These findings underscore the importance of blood pressure control in midlife to mitigate dementia risk. [ABSTRACT FROM AUTHOR]

We conducted a European‐only and transancestral genome‐wide association meta‐analysis in 72,147 stroke patients and 823,869 controls using data from UK Biobank (UKB) and the MEGASTROKE consortium. We identified an exonic polymorphism in NOS3 (rs1799983, p.Glu298Asp; p = 2.2E‐8, odds ratio [OR] = 1.05, 95% confidence interval [CI] = 1.04–1.07) and variants in an intron of COL4A1 (rs9521634; p = 3.8E‐8, OR = 1.04, 95% CI = 1.03–1.06) and near DYRK1A (rs720470; p = 6.1E‐9, OR = 1.05, 95% CI = 1.03–1.07) at genome‐wide significance for stroke. Effect sizes of known stroke loci were highly correlated between UKB and MEGASTROKE. Using Mendelian randomization, we further show that genetic variation in the nitric oxide synthase–nitric oxide pathway in part affects stroke risk via variation in blood pressure. Ann Neurol 2018;84:934–939 [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether the effect of blood pressure (BP) on mortality differs by levels of cognitive function. The associations of brachial systolic BP, diastolic BP, mean arterial pressure (MAP), and pulse pressure with all-cause mortality were prospectively explored (follow-up 7.0±2.2 years) in 660 community-dwelling individuals (≥60 years) using adjusted Cox models, stratified by cognitive impairment (Mini-Mental State Examination [MMSE] <24). No association between brachial BP variables and mortality was shown for the total sample in quartiles analysis; however, MAP in the highest quartile, compared with the second, was associated with mortality (hazard ratio, 1.85; 95% confidence intervals, 1.09-3.12) among cognitively impaired individuals. The fractional-polynomials approach for BP confirmed this finding and further showed, solely in the MMSE <24 subcohort, U-shaped trends of MAP and systolic BP, with increased mortality risk in extremely low or high values; no such pattern was evident for patients with MMSE ≥24. Elderly individuals with cognitive impairment might be more susceptible to the detrimental effects of low and elevated MAP and systolic BP. [ABSTRACT FROM AUTHOR]