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Background: Cumulative exposures to obesity, hypertension, and physical inactivity from midlife (40-65 years) onwards are three known cardiovascular risk factors for dementia and associated cerebral structural damage. Exactly how early in the lifespan sensitive periods for exposure to these risk factors begin is yet to be established, specifically with respect to onset of cerebral structural changes. We aimed to investigate whether cardiovascular risk across childhood and adolescence is already associated with cerebral structure in regions previously linked with dementia, during young adulthood., Methods: Participants were selected from the Avon Longitudinal Study of Parents and Children (ALSPAC), a UK-based prospective cohort of young people, if they had participated in a neuroimaging sub-study (N = 862). We entered data from repeated clinical assessments into mixed-effects models to estimate baseline and rate of change in body mass index (BMI) and mean arterial pressure (MAP) between ages 7-17 years, and physical activity (PA) between 11-15 years. Linear models assessed whether cardiovascular risk factors were associated with grey matter macrostructural indices (cortical thickness, surface area, volume) in young adulthood (∼20 years)., Findings: BMI was found to be associated with grey matter macrostructure in nodes of Default Mode Network previously found to show atrophy in dementia. Baseline BMI was associated with thickness of precuneus cortex and entorhinal surface area, whilst rate of change in BMI across childhood and adolescence was associated with thickness of parahippocampal and middle temporal gyri and inferior parietal cortex in addition to entorhinal and parahippocampal surface area. Further, we identified associations between baseline MAP and PA and entorhinal surface area. Exploratory whole-brain analyses revealed associations between baseline and rate of change in these cardiovascular risk factors and the cortical thickness, surface area, and volume of broader groups of cortical and subcortical regions., Interpretation: Findings provide preliminary evidence that cerebral structural differences in regions linked to dementia in old age may be legacy of developmental differences associated with cardiovascular risk exposure during early life. This has relevance for lifespan models of dementia risk and timing of preventative interventions. Further work is required to generalise findings beyond this predominantly white, male, and middle-class sample to more diverse cohorts., Funding: NIHR Oxford Health BRC (NIHR203316), Wellcome Trust (203139/Z/16/Z)., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Near-infrared spectroscopy (NIRS) is an optical technique that can be used to non-invasively interrogate haemodynamic changes within skeletal muscle. It can be combined with a short (3-5 min) arterial cuff-occlusion to quantify post-occlusive reactive hyperaemia (PORH). This technique has utility in tracking changes in vascular health in relation to exercise, disease progression or treatment efficacy. However, methods for assessing PORH vary widely and there is little consensus on methodological approaches such as sampling frequency, correction for adipose tissue or the analysis endpoints. The purpose of this review was to: (1) summarise recent advances; (2) compare different methodological approaches and (3) identify current knowledge gaps and future objectives for use of NIRS for vascular assessment. We propose key areas for future work, including optimising occlusion duration and comparing methods of correction for the ischemic stimulus, standardising methods for adjustment of adipose tissue thickness, cross-device comparisons and establishing a standard for minimum sampling rate. Comparisons with alternative methods of capturing PORH or upstream vasodilatory responses would be valuable. Addressing these methodological considerations will aid our understanding of this useful, non-invasive tool for characterising PORH within skeletal muscle and facilitate interpretation of results across studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hendrick, Jamieson, Chiesa, Hughes and Jones.)

Obese adults are often reported to have smaller brain volumes than their non-obese peers. Whether this represents evidence of accelerations in obesity-driven atrophy or is instead a legacy of developmental differences established earlier in the lifespan remains unclear. This study aimed to investigate whether early-life differences in adiposity explain differences in numerous adult brain traits commonly attributed to mid-life obesity. We utilised a two-sample lifecourse Mendelian randomization study in 37,501 adults recruited to UK Biobank (UKB) imaging centers from 2014, with secondary analyses in 6,996 children assessed in the Adolescent Brain Cognitive Development Study (ABCD) recruited from 2018. Exposures were genetic variants for childhood (266 variants) and adult (470 variants) adiposity derived from a GWAS of 407,741 UKB participants. Primary outcomes were adult total brain volume; grey matter volume, thickness, and surface area; white matter volume and hyperintensities; and hippocampus, amygdala, and thalamus volumes at mean age 55 in UKB. Secondary outcomes were equivalent childhood measures collected at mean age 10 in ABCD. In UKB, individuals who were genetically-predicted to have had higher levels of adiposity in childhood were found to have multiple smaller adult brain volumes relative to intracranial volume (e.g. z-score difference in normalised brain volume per category increase in adiposity [95%CI] = -0.20 [-0.28, -0.12]; p = 4 × 10-6). These effect sizes remained essentially unchanged after accounting for birthweight or current adult obesity in multivariable models, whereas most observed adult effects attenuated towards null (e.g. adult z-score [95%CI] for total volume = 0.06 [-0.05,0.17]; p = 0.3). Observational analyses in ABCD showed a similar pattern of changes already present in those with a high BMI by age 10 (z-score [95%CI] = -0.10 [-0.13, -0.07]; p = 8 × 10-13), with follow-up genetic risk score analyses providing some evidence for a causal effect already at this early age. Sensitivity analyses revealed that many of these effects were likely due to the persistence of larger head sizes established in those who gained excess weight in childhood (childhood z-score [95%CI] for intracranial volume = 0.14 [0.05,0.23]; p = 0.002), rather than smaller brain sizes per se. Our data suggest that persistence of early-life developmental differences across the lifecourse may underlie numerous neuroimaging traits commonly attributed to obesity-related atrophy in later life., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)

Background: Excess bodyweight (BMI >25 kg/m 2 ) in midlife (age 40-65 years) has been linked to future cognitive decline and an increased risk of dementia. Whether chronic exposure to excess bodyweight in the early decades of life (<40 years) is associated with compromised cognitive function by midlife, however, remains unclear. This study therefore aimed to test potential bidirectional direct and indirect pathways linking cumulative exposure to excess bodyweight and cognitive function in the early decades of life., Methods: In this longitudinal analysis, harmonised measures of BMI and cognitive function were available in 19 742 participants aged 47-53 years recruited to the 1946 National Survey of Health and Development (n=2131), the 1958 National Child Development Study (n=9385), and the 1970 British Cohort Study (n=8226). Individual BMI trajectories spanning three decades from age 10-40 years were created for each participant and excess bodyweight duration, BMI change between ages, and cumulative excess bodyweight exposure were calculated. Harmonised measures of verbal and non-verbal ability, mathematical ability, and reading ability were used to create a latent factor for childhood cognitive function, and immediate and delayed recall, animal naming, and letter-search speed tests were used for midlife cognitive function. Multivariable linear regression and structural equation models (SEM) were used to test for potential bidirectional relationships between cognition and excess bodyweight in both individual cohorts and pooled datasets while accounting for other potential early-life confounders., Findings: Increases in BMI during adolescence and greater cumulative exposure to excess bodyweight across early life were associated with lower midlife cognitive function in all cohorts (eg, pooled difference in cognitive function per 10 years excess bodyweight duration -0·10; 95% CI -0·12 to -0·08; p<0·001). Further adjustment for childhood cognitive function attenuated many of these associations towards the null (eg, pooled difference in cognitive function per 10 years excess bodyweight duration -0·04; 95% CI -0·06 to -0·02; p=0·001), however, with any remaining associations then fully attenuating once further adjusted for other early-life factors (eg, pooled difference in cognitive function per 10 years excess bodyweight duration 0, -0·03 to 0·01; p=0·38). In the reverse direction, low childhood cognition was associated with greater cumulative exposure to excess bodyweight over the next four decades, although much of this relationship was found to probably be explained via other potentially modifiable upstream early-life factors such as childhood disadvantage. SEM in all cohorts suggested the presence of modest direct and indirect pathways connecting earlier cognitive function to later excess bodyweight, but scarce evidence for an effect of early-life excess bodyweight on cognitive function by midlife., Interpretation: The association between cumulative exposure to excess bodyweight in early life and lower cognitive function in midlife is probably confounded by a persistently lower cognitive function from childhood. Initiatives to improve early-life factors such as childhood disadvantage and education, however, might exert dual but independent benefits on both of these factors before old age., Funding: Alzheimer's Research UK, Diabetes Research and Wellness Foundation, Diabetes UK, British Heart Foundation, and Medical Research Council., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Given limited data regarding the involvement of disadvantaged groups in paediatric diabetes clinical trials, this study aimed to evaluate the socioeconomic representativeness of participants recruited into a multinational clinical trial in relation to regional and national type 1 diabetes reference populations., Methods: Retrospective, cross-sectional evaluation of a subset of adolescent type 1 diabetes cardiorenal intervention trial (AdDIT) participants from Australia (n = 144), Canada (n = 312) and the UK (n = 173). Validated national measures of deprivation were used: the Index of Relative Socioeconomic Disadvantage (IRSD) 2016 (Australia), the Material Resources (MR) dimension of the Canadian Marginalisation index 2016 (Canada) and the Index of Multiple Deprivation (IMD) 2015 (UK). Representativeness was assessed by comparing the AdDIT cohort's distribution of deprivation quintiles with that of the local paediatric type 1 diabetes population (regional), and the broader type 1 diabetes population for which the trial's intervention was targeted (national)., Results: Recruited study cohorts from each country had higher proportions of participants with higher SES, and significant underrepresentation of lower SES, in relation to their national references. The socioeconomic make-up in Australia mirrored that of the regional population (p = 0.99). For Canada, the 2nd least deprived (p = 0.001) and the most deprived quintiles (p < 0.001) were over- and under-represented relative to the regional reference, while the UK featured higher regional and national SES bias with over-representation and under-representation from the least-deprived and most-deprived quintiles (p < 0.0001)., Conclusions: Significant national differences in trial participation of low SES participants were observed, highlighting limitations in access to clinical research and the importance of reporting sociodemographic representation in diabetes clinical trials., Trial Registration: NCT01581476. Registered on 20 April 2012., (© 2023. The Author(s).)

The factors that influence survival during severe infection are unclear. Extracellular chromatin drives pathology, but the mechanisms enabling its accumulation remain elusive. Here, we show that in murine sepsis models, splenocyte death interferes with chromatin clearance through the release of the DNase I inhibitor actin. Actin-mediated inhibition was compensated by upregulation of DNase I or the actin scavenger gelsolin. Splenocyte death and neutrophil extracellular trap (NET) clearance deficiencies were prevalent in individuals with severe COVID-19 pneumonia or microbial sepsis. Activity tracing by plasma proteomic profiling uncovered an association between low NET clearance and increased COVID-19 pathology and mortality. Low NET clearance activity with comparable proteome associations was prevalent in healthy donors with low-grade inflammation, implicating defective chromatin clearance in the development of cardiovascular disease and linking COVID-19 susceptibility to pre-existing conditions. Hence, the combination of aberrant chromatin release with defects in protective clearance mechanisms lead to poor survival outcomes., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Risk stratification is critical for the early identification of high-risk individuals and disease prevention. Here we explored the potential of nuclear magnetic resonance (NMR) spectroscopy-derived metabolomic profiles to inform on multidisease risk beyond conventional clinical predictors for the onset of 24 common conditions, including metabolic, vascular, respiratory, musculoskeletal and neurological diseases and cancers. Specifically, we trained a neural network to learn disease-specific metabolomic states from 168 circulating metabolic markers measured in 117,981 participants with ~1.4 million person-years of follow-up from the UK Biobank and validated the model in four independent cohorts. We found metabolomic states to be associated with incident event rates in all the investigated conditions, except breast cancer. For 10-year outcome prediction for 15 endpoints, with and without established metabolic contribution, a combination of age and sex and the metabolomic state equaled or outperformed established predictors. Moreover, metabolomic state added predictive information over comprehensive clinical variables for eight common diseases, including type 2 diabetes, dementia and heart failure. Decision curve analyses showed that predictive improvements translated into clinical utility for a wide range of potential decision thresholds. Taken together, our study demonstrates both the potential and limitations of NMR-derived metabolomic profiles as a multidisease assay to inform on the risk of many common diseases simultaneously., (© 2022. The Author(s).)

Inflammation plays a crucial role in the onset and development of atherosclerosis. Periodontitis is a common chronic disease linked to other chronic inflammatory diseases such as atherosclerotic cardiovascular disease (ASCVD). The mechanistic pathways underlying this association are yet to be fully understood. This critical review aims at discuss the role of neutrophils in mediating the relationship between periodontitis and ASCVD. Systemic inflammation triggered by periodontitis could lead to adaptations in hematopoietic stem and progenitor cells (HSPCs) resulting in trained granulopoiesis in the bone marrow, thereby increasing the production of neutrophils and driving the hyper-responsiveness of these abundant innate-immune cells. These alterations may contribute to the onset, progression, and complications of atherosclerosis. Despite the emerging evidence suggesting that the treatment of periodontitis improves surrogate markers of cardiovascular disease, the resolution of periodontitis may not necessarily reverse neutrophil hyper-responsiveness since the hyper-inflammatory re-programming of granulopoiesis can persist long after the inflammatory inducers are removed. Novel and targeted approaches to manipulate neutrophil numbers and functions are warranted within the context of the treatment of periodontitis and also to mitigate its potential impact on ASCVD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Irwandi, Chiesa, Hajishengallis, Papayannopoulos, Deanfield and D’Aiuto.)

Background and Aims: Perinatal HIV infection (PHIV) and prolonged use of antiretroviral therapy (ART) may increase the likelihood of developing subclinical vascular dysfunction at an early age. We conducted a systematic review to assess the effect of PHIV and ART on intima-media thickness (IMT), arterial stiffness and endothelial function in individuals aged 6-25 years., Methods: Medline, Embase and Web of Science were searched, and studies screened by two independent reviewers. We performed a meta-analysis on selected studies reporting on IMT., Results: A total of 680 studies were retrieved from the databases, with 21 studies deemed eligible for qualitative analysis. There were few studies assessing IMT, arterial stiffness and endothelial function. More than half of the studies found either increased IMT, stiffer arteries or impaired endothelial function in PHIV compared to uninfected controls. A minority of the studies reported that the two groups had similar vascular parameters, a conflicting finding. There was a lack of standardisation for IMT assessment and reporting in numerous studies. In a meta-analysis of seven studies with matching methodologies, IMT was higher in PHIV compared to uninfected controls, (mean difference, 0.05 (0.01-0.09; p = 0.01) but heterogeneity between the studies was substantial (I 2 , 96.7%; p < 0.001)., Conclusions: PHIV may affect vascular structure and function. Existing studies are generally small, often contradictory, and predominantly cross-sectional in design. Further studies are required to understand vascular health in PHIV to identify cardiovascular disease risk and improve interventional strategies aimed at prevention and treatment of early vascular changes in this population., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Aims/hypothesis: We hypothesised that adolescents with type 1 diabetes with a urinary albumin/creatinine ratio (ACR) in the upper tertile of the normal range (high ACR) are at greater risk of three-step diabetic retinopathy progression (3DR) independent of glycaemic control., Methods: This was a prospective observational study in 710 normoalbuminuric adolescents with type 1 diabetes from the non-intervention cohorts of the Adolescent Cardio-Renal Intervention Trial (AdDIT). Participants were classified as 'high ACR' or 'low ACR' (lowest and middle ACR tertiles) using baseline standardised log 10 ACR. The primary outcome, 3DR, was determined from centrally graded, standardised two-field retinal photographs. 3DR risk was determined using multivariable Cox regression for the effect of high ACR, with HbA 1c , BP, LDL-cholesterol and BMI as covariates; diabetes duration was the time-dependent variable., Results: At baseline mean ± SD age was 14.3 ± 1.6 years and mean ± SD diabetes duration was 7.2 ± 3.3 years. After a median of 3.2 years, 83/710 (12%) had developed 3DR. In multivariable analysis, high ACR (HR 2.1 [1.3, 3.3], p=0.001), higher mean IFCC HbA 1c (HR 1.03 [1.01, 1.04], p=0.001) and higher baseline diastolic BP SD score (HR 1.43 [1.08, 1.89], p=0.01) were independently associated with 3DR risk., Conclusions/interpretation: High ACR is associated with greater risk of 3DR in adolescents, providing a target for future intervention studies., Trial Registration: isrctn.org ISRCTN91419926., (© 2022. The Author(s).)

Background Low-grade inflammation in the young may contribute to the early development of cardiovascular disease. We assessed whether circulating levels of glycoprotein acetyls (GlycA) were better able to predict the development of adverse cardiovascular disease risk profiles compared with the more commonly used biomarker high-sensitivity CRP (C-reactive protein). Methods and Results A total of 3306 adolescents and young adults from the Avon Longitudinal Study of Parents and Children (mean age, 15.4±0.3; n=1750) and Cardiovascular Risk in Young Finns Study (mean age, 32.1±5.0; n=1556) were included. Baseline associations between inflammatory biomarkers, body composition, cardiovascular risk factors, and subclinical measures of vascular dysfunction were assessed cross-sectionally in both cohorts. Prospective risk of developing hypertension and metabolic syndrome during 9-to-10-year follow-up were also assessed as surrogate markers for future cardiovascular risk. GlycA showed greater within-subject correlation over 9-to-10-year follow-up in both cohorts compared with CRP, particularly in the younger adolescent group (r=0.36 versus 0.07). In multivariable analyses, GlycA was found to associate with multiple lifestyle-related cardiovascular disease risk factors, cardiometabolic risk factor burden, and vascular dysfunction (eg, mean difference in flow-mediated dilation=-1.2 [-1.8, -0.7]% per z-score increase). In contrast, CRP levels appeared predominantly driven by body mass index and showed little relationship to any measured cardiovascular risk factors or phenotypes. In both cohorts, only GlycA predicted future risk of both hypertension (risk ratio [RR], ≈1.1 per z-score increase for both cohorts) and metabolic syndrome (RR, ≈1.2-1.3 per z-score increase for both cohorts) in 9-to-10-year follow-up. Conclusions Low-grade inflammation captured by the novel biomarker GlycA is associated with adverse cardiovascular risk profiles from as early as adolescence and predicts future risk of hypertension and metabolic syndrome in up to 10-year follow-up. GlycA is a stable inflammatory biomarker which may capture distinct sources of inflammation in the young and may provide a more sensitive measure than CRP for detecting early cardiovascular risk.

Objective: In children aged 8--9 years, we examined the associations of linear and abdominal circumference growth during critical stages of prenatal and postnatal development with six vascular measurements commonly used as early markers of atherosclerosis and later cardiovascular disease (CVD) risk., Methods: In 724 children from the UK Southampton Women's Survey mother--offspring cohort, offspring length/height and abdominal circumference measurements were collected at 10 ages between 11 weeks' gestation and age 8--9 years. Using residual growth modelling and linear regression, we examined the independent associations between growth and detailed vascular measures made at 8--9 years., Results: Postnatal linear and abdominal circumference growth were associated with higher childhood SBP and carotid--femoral pulse wave velocity, whereas prenatal growth was not. For example, 1SD faster abdominal circumference gain between ages 3 and 6 years was associated with 2.27 [95% confidence interval (CI): 1.56--2.98] mmHg higher SBP. In contrast, faster abdominal circumference gain before 19 weeks' gestation was associated with greater carotid intima--media thickness [0.009 mm (0.004--0.015) per 1SD larger 19-week abdominal circumference), whereas later growth was not. We found no strong associations between prenatal or postnatal growth and DBP or measures of endothelial function., Conclusion: Higher postnatal linear growth and adiposity gain are related to higher SBP and carotid--femoral pulse wave velocity in childhood. In contrast, faster growth in early gestation is associated with greater childhood carotid intima--media thickness, perhaps resulting from subtle changes in vascular structure that reflect physiological adaptations rather than subclinical atherosclerosis., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

OBJECTIVE: Inflammation, oxidative stress, and endothelial dysfunction are known to contribute to ischemia-reperfusion injury. Remote ischemic preconditioning (RIPC) protects from endothelial dysfunction and the damage induced by ischemiareperfusion. Using intensive periodontal treatment (IPT), an established human model of acute systemic inflammation, we investigated whether RIPC prevents endothelial dysfunction and modulates systemic levels of inflammation and oxidative stress. APPROACH AND RESULTS: Forty-nine participants with periodontitis were randomly allocated to receive either 3 cycles of ischemia-reperfusion on the upper limb (N=24, RIPC) or a sham procedure (N=25, control) before IPT. Endothelial function assessed by flow-mediated dilatation of the brachial artery, inflammatory cytokines, markers of vascular injury, and oxidative stress were evaluated at baseline, day 1, and day 7 after IPT. Twenty-four hours post-IPT, the RIPC group had lower levels of IL-10 (interleukin-10) and IL-12 (interleukin-12) compared with the control group (P<0.05). RIPC attenuated the IPTinduced increase in IL-1β (interleukin-1β), E-selectin, sICAM-3 (soluble intercellular adhesion molecule 3), and sTM (soluble thrombomodulin) levels between the baseline and day 1 (P for interaction <0.1). Conversely, oxidative stress was differentially increased at day1 in the RIPC group compared with the control group (P for interaction <0.1). This was accompanied by a better flow-mediated dilatation (mean difference 1.75% [95% CI, 0.428–3.07], P=0.011). After 7 days from IPT, most of the inflammatory markers, endothelial-dependent and -independent vasodilation, were similar between groups. CONCLUSIONS: RIPC prevented acute endothelial dysfunction by modulation of inflammation and oxidation processes in patients with periodontitis following exposure to an acute inflammatory stimulus. REGISTRATION: URL: https://clinicaltrials.gov/ct2/show/NCT03072342; Unique identifier: NCT03072342.

Cardiovascular disease (CVD) remains the main cause of morbidity and mortality in individuals with type 1 diabetes (T1D). Adolescence appears to be a critical time for the development of early subclinical manifestations of CVD, with these changes likely driven by a deterioration in glycemic control during the progression through puberty, combined with the emergence of numerous other traditional cardiometabolic risk factors (e.g., hypertension, dyslipidemia, smoking, alcohol use, obesity, etc.) which emerge at this age. Although hemoglobin A1C has long been the primary focus of screening and treatment strategies, glycemic control remains poor in youth with T1D. Furthermore, screening for cardiovascular risk factors-which are often elevated in youth with T1D-is suboptimal, and use of pharmacological interventions for hypertension and dyslipidemia remains low. As such, there is a clear need not only for better screening strategies for CVD risk factors in youth, but also early interventions to reduce these, if future CVD events have to be prevented. Accumulating evidence has recently suggested that early increases in urinary albumin excretion, even within the normal range, may identify adolescents with T1D who are at an increased risk of complications, and results from pharmacological intervention with statins and ACE inhibitors in these individuals have been encouraging. These data join a growing evidence highlighting the need for a whole-life approach to prevention starting from childhood if efforts to improve CVD outcomes and related mortality in T1D are to be maintained., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Chiesa and Marcovecchio.)

Background: It is well-established that what is good for the heart is good for the brain. Vascular factors such as hypertension, diabetes, and high cholesterol, and genetic factors such as the apolipoprotein E4 allele increase the risk of developing both cardiovascular disease and dementia. However, the mechanisms underlying the heart-brain association remain unclear. Recent evidence suggests that impairments in vascular phenotypes and cerebrovascular reactivity (CVR) may play an important role in cognitive decline. The Heart and Brain Study combines state-of-the-art vascular ultrasound, cerebrovascular magnetic resonance imaging (MRI) and cognitive testing in participants of the long-running Whitehall II Imaging cohort to examine these processes together. This paper describes the study protocol, data pre-processing and overarching objectives., Methods and Design: The 775 participants of the Whitehall II Imaging cohort, aged 65 years or older in 2019, have received clinical and vascular risk assessments at 5-year-intervals since 1985, as well as a 3T brain MRI scan and neuropsychological tests between 2012 and 2016 (Whitehall II Wave MRI-1). Approximately 25% of this cohort are selected for the Heart and Brain Study , which involves a single testing session at the University of Oxford (Wave MRI-2). Between 2019 and 2023, participants will undergo ultrasound scans of the ascending aorta and common carotid arteries, measures of central and peripheral blood pressure, and 3T MRI scans to measure CVR in response to 5% carbon dioxide in air, vessel-selective cerebral blood flow (CBF), and cerebrovascular lesions. The structural and diffusion MRI scans and neuropsychological battery conducted at Wave MRI-1 will also be repeated. Using this extensive life-course data, the Heart and Brain Study will examine how 30-year trajectories of vascular risk throughout midlife (40-70 years) affect vascular phenotypes, cerebrovascular health, longitudinal brain atrophy and cognitive decline at older ages., Discussion: The study will generate one of the most comprehensive datasets to examine the longitudinal determinants of the heart-brain association. It will evaluate novel physiological processes in order to describe the optimal window for managing vascular risk in order to delay cognitive decline. Ultimately, the Heart and Brain Study will inform strategies to identify at-risk individuals for targeted interventions to prevent or delay dementia., Competing Interests: JD reports provision of medical consulting for the Brain Protection Company Ltd. MC has received royalties for the commercial licensing of FSL and VEASL software tools. TO has received royalties for the commercial licensing of a patent relating to VEASL analysis. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Suri, Bulte, Chiesa, Ebmeier, Jezzard, Rieger, Pitt, Griffanti, Okell, Craig, Chappell, Blockley, Kivimäki, Singh-Manoux, Khir, Hughes, Deanfield, Jensen, Green, Sigutova, Jansen, Zsoldos and Mackay.)

Background: Aortic stiffness is closely linked with cardiovascular diseases (CVDs), but recent studies suggest that it is also a risk factor for cognitive decline and dementia. However, the brain changes underlying this risk are unclear. We examined whether aortic stiffening during a 4-year follow-up in mid-to-late life was associated with brain structure and cognition in the Whitehall II Imaging Sub-study., Methods and Findings: The Whitehall II Imaging cohort is a randomly selected subset of the ongoing Whitehall II Study, for which participants have received clinical follow-ups for 30 years, across 12 phases. Aortic pulse wave velocity (PWV) was measured in 2007-2009 (Phase 9) and at a 4-year follow-up in 2012-2013 (Phase 11). Between 2012 and 2016 (Imaging Phase), participants received a multimodal 3T brain magnetic resonance imaging (MRI) scan and cognitive tests. Participants were selected if they had no clinical diagnosis of dementia and no gross brain structural abnormalities. Voxel-based analyses were used to assess grey matter (GM) volume, white matter (WM) microstructure (fractional anisotropy (FA) and diffusivity), white matter lesions (WMLs), and cerebral blood flow (CBF). Cognitive outcomes were performance on verbal memory, semantic fluency, working memory, and executive function tests. Of 542 participants, 444 (81.9%) were men. The mean (SD) age was 63.9 (5.2) years at the baseline Phase 9 examination, 68.0 (5.2) at Phase 11, and 69.8 (5.2) at the Imaging Phase. Voxel-based analysis revealed that faster rates of aortic stiffening in mid-to-late life were associated with poor WM microstructure, viz. lower FA, higher mean, and radial diffusivity (RD) in 23.9%, 11.8%, and 22.2% of WM tracts, respectively, including the corpus callosum, corona radiata, superior longitudinal fasciculus, and corticospinal tracts. Similar voxel-wise associations were also observed with follow-up aortic stiffness. Moreover, lower mean global FA was associated with faster rates of aortic stiffening (B = -5.65, 95% CI -9.75, -1.54, Bonferroni-corrected p < 0.0125) and higher follow-up aortic stiffness (B = -1.12, 95% CI -1.95, -0.29, Bonferroni-corrected p < 0.0125). In a subset of 112 participants who received arterial spin labelling scans, faster aortic stiffening was also related to lower cerebral perfusion in 18.4% of GM, with associations surviving Bonferroni corrections in the frontal (B = -10.85, 95% CI -17.91, -3.79, p < 0.0125) and parietal lobes (B = -12.75, 95% CI -21.58, -3.91, p < 0.0125). No associations with GM volume or WMLs were observed. Further, higher baseline aortic stiffness was associated with poor semantic fluency (B = -0.47, 95% CI -0.76 to -0.18, Bonferroni-corrected p < 0.007) and verbal learning outcomes (B = -0.36, 95% CI -0.60 to -0.12, Bonferroni-corrected p < 0.007). As with all observational studies, it was not possible to infer causal associations. The generalisability of the findings may be limited by the gender imbalance, high educational attainment, survival bias, and lack of ethnic and socioeconomic diversity in this cohort., Conclusions: Our findings indicate that faster rates of aortic stiffening in mid-to-late life were associated with poor brain WM microstructural integrity and reduced cerebral perfusion, likely due to increased transmission of pulsatile energy to the delicate cerebral microvasculature. Strategies to prevent arterial stiffening prior to this point may be required to offer cognitive benefit in older age., Trial Registration: ClinicalTrials.gov NCT03335696., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: JED reports provision of medical consulting for the Brain Protection Company Ltd. The remaining authors have declared that no competing interests exist.

An increased albumin-creatinine ratio within the normal range can identify adolescents at higher risk of developing adverse cardio-renal outcomes as they progress into adulthood. Utilizing a parallel randomized controlled trial and observational cohort study, we characterized the progression of vascular phenotypes throughout this important period and investigated the effect of ACE (angiotensin-converting enzyme) inhibitors and statins in high-risk adolescents. Endothelial function (flow-mediated dilation and reactive hyperemia index) and arterial stiffness (carotid-femoral pulse wave velocity) were assessed in 158 high-risk participants recruited to a randomized, double-blind placebo-controlled 2×2 factorial trial (randomized, placebo-controlled trial) of ACE inhibitors and/or statins in adolescents with type 1 diabetes (AdDIT [Adolescent Type 1 Diabetes cardio-renal Intervention Trial]). Identical measures were also assessed in 215 lower-risk individuals recruited to a parallel observational study. In the randomized, placebo-controlled trial, high-risk patients randomized to ACE inhibitors had improved flow-mediated dilation after 2 to 4 years of follow-up (mean [95% CI]: 6.6% [6.0-7.2] versus 5.3% [4.7-5.9]; P =0.005), whereas no effect was observed following statin use (6.2% [5.5-6.8] versus 5.8% [5.1-6.4]; P =0.358). In the observational study, patients classed as high-risk based on albumin-creatinine ratio showed evidence of endothelial dysfunction at the end of follow-up (flow-mediated dilation=4.8% [3.8-5.9] versus 6.3% [5.8-6.7] for high-risk versus low-risk groups; P =0.015). Neither reactive hyperemia index nor pulse wave velocity were affected by either treatment ( P >0.05 for both), but both were found to increase over the duration of follow-up (0.07 [0.03-0.12]; P =0.001 and 0.5 m/s [0.4-0.6]; P <0.001 for reactive hyperemia index and pulse wave velocity, respectively). ACE inhibitors improve endothelial function in high-risk adolescents as they transition through puberty. The longer-term protective effects of this intervention at this early age remain to be determined. Registration- URL: https://www.clinicaltrials.gov; Unique identifier NCT01581476.

Objectives: To identify biomarkers of renal disease in adolescents with type 1 diabetes (T1D) and to compare findings in adults with T1D., Methods: Twenty-five serum biomarkers were measured, using a Luminex platform, in 553 adolescents (median [interquartile range] age: 13.9 [12.6, 15.2] years), recruited to the Adolescent Type 1 Diabetes Cardio-Renal Intervention Trial. Associations with baseline and final estimated glomerular filtration rate (eGFR), rapid decliner and rapid increaser phenotypes (eGFR slopes <-3 and > 3 mL/min/1.73m 2 /year, respectively), and albumin-creatinine ratio (ACR) were assessed. Results were also compared with those obtained in 859 adults (age: 55.5 [46.1, 64.4) years) from the Scottish Diabetes Research Network Type 1 Bioresource., Results: In the adolescent cohort, baseline eGFR was negatively associated with trefoil factor-3, cystatin C, and beta-2 microglobulin (B2M) (B coefficient[95%CI]: -0.19 [-0.27, -0.12], P = 7.0 × 10 -7 ; -0.18 [-0.26, -0.11], P = 5.1 × 10 -6 ; -0.12 [-0.20, -0.05], P = 1.6 × 10 -3 ), in addition to clinical covariates. Final eGFR was negatively associated with osteopontin (-0.21 [-0.28, -0.14], P = 2.3 × 10 -8 ) and cystatin C (-0.16 [-0.22, -0.09], P = 1.6 × 10 -6 ). Rapid decliner phenotype was associated with osteopontin (OR: 1.83 [1.42, 2.41], P = 7.3 × 10 -6 ), whereas rapid increaser phenotype was associated with fibroblast growth factor-23 (FGF-23) (1.59 [1.23, 2.04], P = 2.6 × 10 -4 ). ACR was not associated with any of the biomarkers. In the adult cohort similar associations with eGFR were found; however, several additional biomarkers were associated with eGFR and ACR., Conclusions: In this young population with T1D and high rates of hyperfiltration, osteopontin was the most consistent biomarker associated with prospective changes in eGFR. FGF-23 was associated with eGFR increases, whereas trefoil factor-3, cystatin C, and B2M were associated with baseline eGFR., (© 2020 The Authors. Pediatric Diabetes published by John Wiley & Sons Ltd.)

Objective: Suboptimal adherence to insulin treatment is a main issue in adolescents with type 1 diabetes. However, to date, there are no available data on adherence to adjunct noninsulin medications in this population. Our aim was to assess adherence to ACE inhibitors and statins and explore potential determinants in adolescents with type 1 diabetes., Research Design and Methods: There were 443 adolescents with type 1 diabetes recruited into the Adolescent Type 1 Diabetes Cardio-Renal Intervention Trial (AdDIT) and exposed to treatment with two oral drugs-an ACE inhibitor and a statin-as well as combinations of both or placebo for 2-4 years. Adherence was assessed every 3 months with the Medication Event Monitoring System (MEMS) and pill count., Results: Median adherence during the trial was 80.2% (interquartile range 63.6-91.8) based on MEMS and 85.7% (72.4-92.9) for pill count. Adherence based on MEMS and pill count dropped from 92.9% and 96.3%, respectively, at the first visit to 76.3% and 79.0% at the end of the trial. The percentage of study participants with adherence ≥75% declined from 84% to 53%. A good correlation was found between adherence based on MEMS and pill count ( r = 0.82, P < 0.001). Factors associated with adherence were age, glycemic control, and country., Conclusions: We report an overall good adherence to ACE inhibitors and statins during a clinical trial, although there was a clear decline in adherence over time. Older age and suboptimal glycemic control at baseline predicted lower adherence during the trial, and, predictably, reduced adherence was more prevalent in subjects who subsequently dropped out., (© 2020 by the American Diabetes Association.)

Increased carotid intima-media thickness (cIMT) is reported in both adults and children with human immunodeficiency virus (HIV) in high income settings and is associated with an increased risk of cardiovascular disease, but data from sub-Saharan Africa is lacking.We assessed cIMT using ultrasound in perinatally HIV-infected children aged 6 to 16 years taking antiretroviral therapy (ART) for ≥6 months compared with HIV-uninfected controls in Harare, Zimbabwe. Groups were compared using unpaired t test and potential predictors of cIMT were assessed using multiple linear regression.A total of 117 participants with HIV, of whom 55 (45%) were female and 75 healthy uninfected controls were included. Participants with HIV were younger than uninfected controls, 10.7 (2.4) years versus 11.9 (2.6) years (P = .001). Mean cIMT was 0.40 (0.05) mm in those with HIV versus 0.40 (0.04) mm in healthy controls (P = .377). There was no association between cluster of differentiation 4 count, HIV viral load, and duration on ART and cIMT.Children with HIV taking ART have similar cIMT to uninfected children. Increasing numbers of children with HIV are reaching adulthood and longitudinal studies to assess the effect of long-term HIV and ART on vascular changes are required.

Genetic, experimental and clinical studies have consistently confirmed that inhibition of Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) can result in significant lowering of LDL-C and two fully human PCSK9 monoclonal antibodies have received regulatory approval for use in highrisk patients. Co-administration of PCSK9 with statins has resulted in extremely low LDL-C levels with excellent short-term safety profiles. While results from Phase III clinical trials provided significant evidence about the role of PCSK9 inhibitors in reducing cardiovascular event rates, their impact on mortality remains less clear. PCSK9 inhibitor therapy can be considered for high-risk patients who are likely to experience significant cardiovascular risk reduction., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Aims: High-density lipoprotein (HDL) function may be altered in patients with chronic disease, transforming the particle from a beneficial vasoprotective molecule to a noxious pro-inflammatory equivalent. Adolescents with Type 1 diabetes often have elevated HDL, but its vasoprotective properties and relationship to endothelial function have not been assessed., Methods and Results: Seventy adolescents with Type 1 diabetes (age 10-17 years) and 30 age-matched healthy controls supplied urine samples for the measurement of early renal dysfunction (albumin:creatinine ratio; ACR), blood samples for the assessment of cardiovascular risk factors (lipid profiles, HDL functionality, glycaemic control, and inflammatory risk score), and had their conduit artery endothelial function tested using flow-mediated dilation (FMD). HDL-c levels (1.69 ± 0.41 vs. 1.44 ± 0.29mmol/L; P < 0.001), and glycated haemoglobin (HbA1c) (8.4 ± 1.2 vs. 5.4 ± 0.2%; P < 0.001) were increased in all patients compared with controls. However, increased inflammation and HDL dysfunction were evident only in patients who also had evidence of early renal dysfunction (mean ± standard deviation for high-ACR vs. low-ACR and healthy controls: inflammatory risk score 11.3 ± 2.5 vs. 9.5 ± 2.4 and 9.2 ± 2.4, P < 0.01; HDL-mediated nitric-oxide bioavailability 38.0 ± 8.9 vs. 33.3 ± 7.3 and 25.0 ± 7.7%, P < 0.001; HDL-mediated superoxide production 3.71 ± 3.57 vs. 2.11 ± 3.49 and 1.91 ± 2.47nmol O2 per 250 000 cells, P < 0.05). Endothelial function (FMD) was impaired only in those who had both a high inflammatory risk score and high levels of HDL-c (P < 0.05)., Conclusion: Increased levels of HDL-c commonly observed in individuals with Type 1 diabetes may be detrimental to endothelial function when accompanied by renal dysfunction and chronic inflammation., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Aims: Excessive arterial pulsatility may contribute to cognitive decline and risk of dementia via damage to the fragile cerebral microcirculation. We hypothesized that the intensity of downstream-travelling pulsatile waves measured by wave intensity analysis in the common carotid artery during mid- to late-life would be associated with subsequent cognitive decline., Methods and Results: Duplex Doppler ultrasound was used to calculate peak forward-travelling compression wave intensity (FCWI) within the common carotid artery in 3191 individuals [mean ± standard deviation (SD), age = 61 ± 6 years; 75% male] assessed as part of the Whitehall II study in 2003-05. Serial measures of cognitive function were taken between 2002-04 and 2015-16. The relationship between FCWI and cognitive decline was adjusted for sociodemographic variables, genetic and health-related risk factors, and health behaviours. Mean (SD) 10-year change in standardized global cognitive score was -0.39 (0.18). Higher FCWI at baseline was associated with accelerated cognitive decline during follow-up [difference in 10-year change of global cognitive score per 1 SD higher FCWI = -0.02 (95% confidence interval -0.04 to -0.00); P = 0.03]. This association was largely driven by cognitive changes in individuals with the highest FCWI [Q4 vs. Q1-Q3 = -0.05 (-0.09 to -0.01), P = 0.01], equivalent to an age effect of 1.9 years. Compared to other participants, this group was ∼50% more likely to exhibit cognitive decline (defined as the top 15% most rapid reductions in cognitive function during follow-up) even after adjustments for multiple potential confounding factors [odds ratio 1.49 (1.17-1.88)]., Conclusion: Elevated carotid artery wave intensity in mid- to late-life predicts faster cognitive decline in long-term follow-up independent of other cardiovascular risk factors., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: The link between adiposity, metabolic abnormalities, and arterial disease progression in children and adolescents remains poorly defined. We aimed to assess whether persistent high adiposity levels are associated with increased arterial stiffness in adolescence and any mediation effects by common metabolic risk factors., Methods: We included participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) who had detailed adiposity measurements between the ages 9-17 years and arterial stiffness (carotid to femoral pulse wave velocity [PWV]) measured at age 17 years. Body-mass index (BMI) and waist-to-height ratio were calculated from weight, height, and waist circumference measurements whereas fat mass was assessed using repeated dual-energy x-ray absorptiometry (DEXA) scans. We used total and trunk fat mass indices (FMIs) to classify participants as normal (<75th percentile) or high (>75th percentile) FMI. We classified participants as being metabolically unhealthy if they had three or more of the following risk factors: high levels of systolic blood pressure, triglycerides, or glucose (all >75th percentile) or low levels of high-density lipoprotein (<25th percentile). We used multivariable linear regression analysis to assess the relationship between PWV and exposure to adiposity, and tested for linear trend of PVW levels across ordinal groups. We used latent class growth mixture modelling analysis to assess the effect of longitudinal changes in adiposity indices through adolescence on arterial stiffness., Findings: We studied 3423 participants (1866 [54·5%] female and 1557 [45·5%] male). Total fat mass was positively associated with PWV at age 17 years (0·004 m/s per kg, 95% CI 0·001-0·006; p=0·0081). Persistently high total FMI and trunk FMI between ages 9 and 17 years were related to greater PWV (0·15 m/s per kg/m 2 , 0·05-0·24; p=0·0044 and 0·15 m/s per kg/m 2 , 0·06-0·25; p=0·0021) compared with lower FMI. Metabolic abnormalities amplified the adverse effect of high total FMI on arterial stiffness (PWV 6·0 m/s [95% CI 5·9-6·0] for metabolically healthy participants and 6·2 m/s [5·9-6·4] for metabolically unhealthy participants). Participants who restored normal total FMI in adolescence (PWV 5·8 m/s [5·7-5·9] for metabolically healthy and 5·9 m/s [5·6-6·1] for metabolically unhealthy) had comparable PWV to those who had normal FMI throughout (5·7 m/s [5·7-5·8] for metabolically healthy and 5·9 m/s [5·8-5·9] for metabolically unhealthy)., Interpretation: Persistently high fat mass during adolescence was associated with greater arterial stiffness and was further aggravated by an unfavourable metabolic profile. Reverting to normal FMI in adolescence was associated with normal PWV, suggesting adolescence as an important period for interventions to tackle obesity in the young to maximise long-term vascular health., Funding: UK Medical Research Council, Wellcome Trust, British Heart Foundation, and AFA Insurances., (Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: This case-report characterized the respiratory, cardiovascular, and nutritional/gastrointestinal (GI) responses of a trained individual to a novel ultra-endurance exercise challenge. Case Presentation: A male athlete (age 45 years; V ˙ O 2 max 54.0 mL⋅kg -1 ⋅min -1 ) summited 100 mountains on foot in 25 consecutive days (all elevations >600 m). Measures: Laboratory measures of pulmonary function (spirometry, whole-body plethysmography, and single-breath rebreathe), respiratory muscle function (maximum static mouth-pressures), and cardiovascular structure and function (echocardiography, electrocardiography, large vessel ultrasound, and flow-mediated dilatation) were made at baseline and 48 h post-challenge. Dietary intake (four-day food diary), self-reported GI symptoms and plasma endotoxin concentrations were assessed at baseline, pre/post mid-point, pre/post end-point, and 48 h post-challenge. Results: The challenge was completed in a total exercise time of 142 h (5.3 ± 2.8 h⋅d -1 ), with a distance of 1141 km (42.3 ± 43.9 km⋅d -1 ), and energy expenditure of 80460 kcal (2980 ± 1451 kcal⋅d -1 ). Relative to baseline, there were post-challenge decreases in pulmonary capacities and expiratory flows (≤34%), maximum expiratory mouth-pressure (19%), and maximum voluntary ventilation (29%). Heart rate variability deteriorated, manifesting as a 48% decrease in the root mean square of successive differences and a 70% increase in the low-frequency/high-frequency ratio. Pre- to post-challenge endotoxin concentrations were elevated by 60%, with a maximum increase of 130% after a given stage, congruent with an increased frequency and severity of GI symptoms. Conclusion: The challenge resulted in pulmonary and autonomic dysfunction, endotoxaemia, and GI distress. The findings extend our understanding of the limits of physiological function and may inform medical best-practice for personnel supporting ultra-endurance events.

High-density lipoprotein cholesterol (HDL-c) has long been referred to as 'good cholesterol' due to its apparent inverse relationship with future CVD risk. More recent research has questioned a causal role for HDL-c in this relationship, however, as both genetic studies and numerous large-scale randomised controlled trials have found no evidence of a cardiovascular protective effect when HDL-c levels are raised. Instead, focus has switched to the functional properties of the HDL particle. Evidence suggests that both the composition and function of HDL may be significantly altered in the context of an inflammatory milieu, transforming the particle from a vasoprotective anti-atherogenic particle to a noxious pro-atherogenic equivalent. This review will summarise evidence relating HDL to CVD risk, explore recent evidence characterising changes in the composition and function of HDL that may occur in chronic inflammatory diseases, and discuss the potential for future HDL-modifying therapeutic interventions.

Aims: To determine the impact of smoking and alcohol exposure during adolescence on arterial stiffness at 17 years., Methods and Results: Smoking and alcohol use were assessed by questionnaires at 13, 15, and 17 years in 1266 participants (425 males and 841 females) from the ALSPAC study. Smoking status (smokers and non-smoker) and intensity ('high' ≥100, 'moderate' 20-99, and 'low or never' <20 cigarettes in lifetime) were ascertained. Participants were classified by frequency (low or high) and intensity of drinking [light (LI <2), medium (MI 3-9), and heavy (HI >10 drinks on a typical drinking day)]. Carotid to femoral pulse wave velocity (PWV) was assessed at 17 years [mean ± standard deviation and/or mean difference (95% confidence intervals)]. Current smokers had higher PWV compared with non-smokers (P = 0.003). Higher smoking exposure was associated with higher PWV compared with non-smokers [5.81 ± 0.725 vs. 5.71 ± 0.677 m/s, mean adjusted difference 0.211 (0.087-0.334) m/s, P = 0.001]. Participants who stopped smoking had similar PWV to never smokers (P = 0.160). High-intensity drinkers had increased PWV [HI 5.85 ± 0.8 vs. LI 5.67 ± 0.604 m/s, mean adjusted difference 0.266 (0.055-0.476) m/s, P = 0.013]. There was an additive effect of smoking intensity and alcohol intensity, so that 'high' smokers who were also HI drinkers had higher PWV compared with never-smokers and LI drinkers [mean adjusted increase 0.603 (0.229-0.978) m/s, P = 0.002]., Conclusion: Smoking exposure even at low levels and intensity of alcohol use were associated individually and together with increased arterial stiffness. Public health strategies need to prevent adoption of these habits in adolescence to preserve or restore arterial health.

Background: Body mass index (BMI) has been suggested to be causally related to cardiovascular health in mid-to-late life, but this has not been explored systematically at younger ages - nor with detailed cardiovascular phenotyping. Recall-by-Genotype (RbG) is an approach that enables the collection of precise phenotypic measures in smaller studies, whilst maintaining statistical power and ability for causal inference., Methods: In this study, we used a combination of conventional multivariable regression analysis, Mendelian randomization (MR) and sub-sample RbG methodologies to estimate the causal effect of BMI on gross-level and detailed cardiovascular health in healthy participants from the Avon Longitudinal Study of Parents and Children at age 17 (N=1420-3108 for different outcomes) and an independent sample from the same cohort (for RbG) study at age 21 (N=386-418)., Results: In both MR and RbG analyses, results suggested that higher BMI causes higher blood pressure (BP) and left ventricular mass index (LVMI) in young adults (e.g., difference in LVMI per kg/m 2 using MR: 1.07g/m 2.7 ; 95% CI: 0.62, 1.52; P =3.87x10 -06 and per 3.58kg/m 2 using RbG: 1.65g/m 2.7 95% CI: 0.83, 2.47; P =0.0001). Additionally, RbG results suggested a causal role of higher BMI on higher stroke volume (SV: difference per 3.58kg/m 2 : 1.49ml/m 2.04 ; 95% CI: 0.62, 2.35; P =0.001) and cardiac output (CO: difference per 3.58kg/m 2 : 0.11l/min/m 1.83 ; 95% CI: 0.03, 0.19; P =0.01) but no strong evidence for a causal role on systemic vascular resistance or total arterial compliance. Neither analysis supported a causal role of higher BMI on heart rate., Conclusions: Complementary MR and RbG causal methodologies, together with a range of sensitivity analyses, suggest that higher BMI is likely to cause worse cardiovascular health, specifically higher BP and LVMI, even in youth. Higher BMI also resulted in increased CO in the RbG study, which appeared to be solely driven by SV, as neither MR nor RbG analyses suggested a causal effect of BMI on heart rate. These consistent results support efforts to reduce BMI from a young age to prevent later adverse cardiovascular health and illustrate the potential for phenotypic resolution with maintained analytical power using RbG.

Objective: Baseline data from the Adolescent Type 1 Diabetes Cardio-Renal Intervention Trial (AdDIT) indicated that tertiles of urinary albumin-to-creatinine ratios (ACRs) in the normal range at age 10-16 years are associated with risk markers for diabetic nephropathy (DN) and cardiovascular disease (CVD). We aimed to determine whether the top ACR tertile remained associated with DN and CVD risk over the 2-4-year AdDIT study., Research Design and Methods: One hundred fifty adolescents (mean age 14.1 years [SD 1.6]) with baseline ACR in the upper tertile (high-ACR group) recruited to the AdDIT trial, who remained untreated, and 396 (age 14.3 years [1.6]) with ACR in the middle and lower tertiles (low-ACR group), who completed the parallel AdDIT observational study, were evaluated prospectively with assessments of ACR and renal and CVD markers, combined with carotid intima-media thickness (cIMT) at baseline and end of study., Results: After a median follow-up of 3.9 years, the cumulative incidence of microalbuminuria was 16.3% in the high-ACR versus 5.5% in the low-ACR group (log-rank P < 0.001). Cox models showed independent contributions of the high-ACR group (hazard ratio 4.29 [95% CI 2.08-8.85]) and HbA 1c (1.37 [1.10-1.72]) to microalbuminuria risk. cIMT change from baseline was significantly greater in the high- versus low-ACR group (mean difference 0.010 mm [0.079], P = 0.006). Changes in estimated glomerular filtration rate, systolic blood pressure, and hs-CRP were also significantly greater in the high-ACR group ( P < 0.05)., Conclusions: ACR at the higher end of the normal range at the age of 10-16 years is associated with an increased risk of progression to microalbuminuria and future CVD risk, independently of HbA 1c ., (© 2018 by the American Diabetes Association.)

Objective: To evaluate the association between a clustering of cardio-metabolic risk factors in parents and the development of microalbuminuria (MA) in their offspring with childhood-onset type 1 diabetes (T1D)., Methods: The study population comprised 53 parents (mean age [±SD]: 56.7±6.2 years) of 35 T1D young people with MA (MA+) and 86 parents (age: 56.1±6.3 years) of 50 matched offspring with normoalbuminuria (MA-), who underwent clinical, biochemical and cardiovascular imaging assessments. The primary study endpoint was the difference between parents from the MA+ and MA- groups in a cardio-metabolic risk score, calculated as the average value of the standardized measures (z-scores) for waist circumference, blood pressure, fasting glucose, insulin, HDL-cholesterol and triglycerides levels. Cardiovascular parameters, including carotid intima-media thickness (cIMT), flow-mediated dilatation (FMD) and pulse wave velocity (PWV), were also assessed. A DXA scan was performed to assess body composition., Results: The cardio-metabolic risk score was significantly higher in parents of MA+ compared to parents of MA- offspring (mean [95% CI]: 1.066[0.076; 2.056] vs -0.268[-0.997; 0.460], P = .03). Parents of MA+ offspring had slightly higher values of waist circumference, lipids, insulin and blood pressure, although only diastolic blood pressure was statistically different between the 2 groups (P = .0085). FMD, cIMT, PWV (all P > .3), and DXA parameters (all P > .2) were not significantly different between the 2 groups., Conclusions: Parents of young offspring with childhood-onset T1D and MA showed an abnormal metabolic profile, reflected by a calculated risk score. The finding supports the role of a familial predisposition to risk of developing diabetic nephropathy., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Among adolescents with type 1 diabetes, rapid increases in albumin excretion during puberty precede the development of microalbuminuria and macroalbuminuria, long-term risk factors for renal and cardiovascular disease. We hypothesized that adolescents with high levels of albumin excretion might benefit from angiotensin-converting-enzyme (ACE) inhibitors and statins, drugs that have not been fully evaluated in adolescents., Methods: We screened 4407 adolescents with type 1 diabetes between the ages of 10 and 16 years of age and identified 1287 with values in the upper third of the albumin-to-creatinine ratios; 443 were randomly assigned in a placebo-controlled trial of an ACE inhibitor and a statin with the use of a 2-by-2 factorial design minimizing differences in baseline characteristics such as age, sex, and duration of diabetes. The primary outcome for both interventions was the change in albumin excretion, assessed according to the albumin-to-creatinine ratio calculated from three early-morning urine samples obtained every 6 months over 2 to 4 years, and expressed as the area under the curve. Key secondary outcomes included the development of microalbuminuria, progression of retinopathy, changes in the glomerular filtration rate, lipid levels, and measures of cardiovascular risk (carotid intima-media thickness and levels of high-sensitivity C-reactive protein and asymmetric dimethylarginine)., Results: The primary outcome was not affected by ACE inhibitor therapy, statin therapy, or the combination of the two. The use of an ACE inhibitor was associated with a lower incidence of microalbuminuria than the use of placebo; in the context of negative findings for the primary outcome and statistical analysis plan, this lower incidence was not considered significant (hazard ratio, 0.57; 95% confidence interval, 0.35 to 0.94). Statin use resulted in significant reductions in total, low-density lipoprotein, and non-high-density lipoprotein cholesterol levels, in triglyceride levels, and in the ratio of apolipoprotein B to apolipoprotein A1, whereas neither drug had significant effects on carotid intima-media thickness, other cardiovascular markers, the glomerular filtration rate, or progression of retinopathy. Overall adherence to the drug regimen was 75%, and serious adverse events were similar across the groups., Conclusions: The use of an ACE inhibitor and a statin did not change the albumin-to-creatinine ratio over time. (Funded by the Juvenile Diabetes Research Foundation and others; AdDIT ClinicalTrials.gov number, NCT01581476 .).

Intense, large muscle mass exercise increases circulating microvesicles, but our understanding of microvesicle dynamics and mechanisms inducing their release remains limited. However, increased vascular shear stress is generally thought to be involved. Here, we manipulated exercise-independent and exercise-dependent shear stress using systemic heat stress with localized single-leg cooling (low shear) followed by single-leg knee extensor exercise with the cooled or heated leg (Study 1, n  = 8) and whole-body passive heat stress followed by cycling (Study 2, n  = 8). We quantified femoral artery shear rates (SRs) and arterial and venous platelet microvesicles (PMV-CD41 + ) and endothelial microvesicles (EMV-CD62E + ). In Study 1, mild passive heat stress while one leg remained cooled did not affect [microvesicle] ( P  ≥ 0.05). Single-leg knee extensor exercise increased active leg SRs by ~12-fold and increased arterial and venous [PMVs] by two- to threefold, even in the nonexercising contralateral leg ( P  < 0.05). In Study 2, moderate whole-body passive heat stress increased arterial [PMV] compared with baseline (mean±SE, from 19.9 ± 1.5 to 35.5 ± 5.4 PMV . μ L -1. 10 3 , P  < 0.05), and cycling with heat stress increased [PMV] further in the venous circulation (from 27.5 ± 2.2 at baseline to 57.5 ± 7.2 PMV . μ L -1. 10 3 during cycling with heat stress, P  < 0.05), with a tendency for increased appearance of PMV across exercising limbs. Taken together, these findings demonstrate that whole-body heat stress may increase arterial [PMV], and intense exercise engaging either large or small muscle mass promote PMV formation locally and systemically, with no influence upon [EMV]. Local shear stress, however, does not appear to be the major stimulus modulating PMV formation in healthy humans., (© 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Peripheral arterial disease (PAD) is a common atherosclerotic condition affecting the lower extremities. PAD patients share similar cardiovascular risk factors to coronary artery disease patients and suffer from increased cardiovascular morbidity and mortality. Statins have been widely used in coronary artery disease patients but have been underused in patients with PAD. In the current review, we present data, which support the beneficial role of statins in both reducing cardiovascular events and improving symptom-related outcomes in PAD patients. Alongside their lipid lowering effects, their pleiotropic actions are also discussed. Recent guidelines, which strongly recommend the administration of statins in PAD patients, are also presented., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

New Findings: What is the central question of this study? Skin and muscle blood flow increases with heating and decreases with cooling, but the temperature-sensitive mechanisms underlying these responses are not fully elucidated. What is the main finding and its importance? We found that local tissue hyperaemia was related to elevations in ATP release from erythrocytes. Increasing intravascular ATP augmented skin and tissue perfusion to levels equal or above thermal hyperaemia. ATP release from isolated erythrocytes was altered by heating and cooling. Our findings suggest that erythrocytes are involved in thermal regulation of blood flow via modulation of ATP release. Local tissue perfusion changes with alterations in temperature during heating and cooling, but the thermosensitivity of the vascular ATP signalling mechanisms for control of blood flow during thermal interventions remains unknown. Here, we tested the hypotheses that the release of the vasodilator mediator ATP from human erythrocytes, but not from endothelial cells or other blood constituents, is sensitive to both increases and reductions in temperature and that increasing intravascular ATP availability with ATP infusion would potentiate thermal hyperaemia in limb tissues. We first measured blood temperature, brachial artery blood flow and plasma [ATP] during passive arm heating and cooling in healthy men and found that they increased by 3.0 ± 1.2°C, 105 ± 25 ml min -1  °C -1 and twofold, respectively, (all P < 0.05) with heating, but decreased or remained unchanged with cooling. In additional men, infusion of ATP into the brachial artery increased skin and deep tissue perfusion to levels equal or above thermal hyperaemia. In isolated erythrocyte samples exposed to different temperatures, ATP release increased 1.9-fold from 33 to 39°C (P < 0.05) and declined by ∼50% at 20°C (P < 0.05), but no changes were observed in cultured human endothelial cells, plasma or serum samples. In conclusion, increases in plasma [ATP] and skin and deep tissue perfusion with limb heating are associated with elevations in ATP release from erythrocytes, but not from endothelial cells or other blood constituents. Erythrocyte ATP release is also sensitive to temperature reductions, suggesting that erythrocytes may function as thermal sensors and ATP signalling generators for control of tissue perfusion during thermal interventions., (© 2016 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Cardiovascular strain and hyperthermia are thought to be important factors limiting exercise capacity in heat-stressed humans, however, the contribution of elevations in skin (T sk ) versus whole body temperatures on exercise capacity has not been characterized. To ascertain their relationships with exercise capacity, blood temperature (T B ), oxygen uptake (V̇O 2 ), brain perfusion (MCA V mean ), locomotor limb hemodynamics, and hematological parameters were assessed during incremental cycling exercise with elevated skin (mild hyperthermia; HYP mild ), combined core and skin temperatures (moderate hyperthermia; HYP mod ), and under control conditions. Both hyperthermic conditions increased T sk versus control (6.2 ± 0.2°C; P < 0.001), however, only HYP mod increased resting T B , leg blood flow and cardiac output (Q̇), but not MCA V mean Throughout exercise, T sk remained elevated in both hyperthermic conditions, whereas only T B was greater in HYP mod At exhaustion, oxygen uptake and exercise capacity were reduced in HYP mod in association with lower leg blood flow, MCA V mean and mean arterial pressure (MAP), but similar maximal heart rate and T B The attenuated brain and leg perfusion with hyperthermia was associated with a plateau in MCA and two-legged vascular conductance (VC). Mechanistically, the falling MCA VC was coupled to reductions in PaCO 2 , whereas the plateau in leg vascular conductance was related to markedly elevated plasma [NA] and a plateau in plasma ATP These findings reveal that whole-body hyperthermia, but not skin hyperthermia, compromises exercise capacity in heat-stressed humans through the early attenuation of brain and active muscle blood flow., (© 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Purpose of Review: Continuous wave near infrared spectroscopy (CW NIRS) provides non-invasive technology to measure relative changes in oxy- and deoxy-haemoglobin in a dynamic environment. This allows determination of local skeletal muscle O 2 saturation, muscle oxygen consumption ([Formula: see text]) and blood flow. This article provides a brief overview of the use of CW NIRS to measure exercise-limiting factors in skeletal muscle., Recent Findings: NIRS parameters that measure O 2 delivery and capacity to utilise O 2 in the muscle have been developed based on response to physiological interventions and exercise. NIRS has good reproducibility and agreement with gold standard techniques and can be used in clinical populations where muscle oxidative capacity or oxygen delivery (or both) are impaired. CW NIRS has limitations including: the unknown contribution of myoglobin to the overall signals, the impact of adipose tissue thickness, skin perfusion during exercise, and variations in skin pigmentation. These, in the main, can be circumvented through appropriate study design or measurement of absolute tissue saturation., Summary: CW NIRS can assess skeletal muscle O 2 delivery and utilisation without the use of expensive or invasive procedures and is useable in large population-based samples, including older adults.

The influence of temperature on the hemodynamic adjustments to direct passive heat stress within the leg's major arterial and venous vessels and compartments remains unclear. Fifteen healthy young males were tested during exposure to either passive whole body heat stress to levels approaching thermal tolerance [core temperature (Tc) + 2°C; study 1; n = 8] or single leg heat stress (Tc + 0°C; study 2; n = 7). Whole body heat stress increased perfusion and decreased oscillatory shear index in relation to the rise in leg temperature (Tleg) in all three major arteries supplying the leg, plateauing in the common and superficial femoral arteries before reaching severe heat stress levels. Isolated leg heat stress increased arterial blood flows and shear patterns to a level similar to that obtained during moderate core hyperthermia (Tc + 1°C). Despite modest increases in great saphenous venous (GSV) blood flow (0.2 l/min), the deep venous system accounted for the majority of returning flow (common femoral vein 0.7 l/min) during intense to severe levels of heat stress. Rapid cooling of a single leg during severe whole body heat stress resulted in an equivalent blood flow reduction in the major artery supplying the thigh deep tissues only, suggesting central temperature-sensitive mechanisms contribute to skin blood flow alone. These findings further our knowledge of leg hemodynamic responses during direct heat stress and provide evidence of potentially beneficial vascular alterations during isolated limb heat stress that are equivalent to those experienced during exposure to moderate levels of whole body hyperthermia., (Copyright © 2016 the American Physiological Society.)

Dehydration hastens the decline in cerebral blood flow (CBF) during incremental exercise, whereas the cerebral metabolic rate for O2 (CMRO2 ) is preserved. It remains unknown whether CMRO2 is also maintained during prolonged exercise in the heat and whether an eventual decline in CBF is coupled to fatigue. Two studies were undertaken. In study 1, 10 male cyclists cycled in the heat for ∼2 h with (control) and without fluid replacement (dehydration) while internal and external carotid artery blood flow and core and blood temperature were obtained. Arterial and internal jugular venous blood samples were assessed with dehydration to evaluate CMRO2 . In study 2, in 8 male subjects, middle cerebral artery blood velocity was measured during prolonged exercise to exhaustion in both dehydrated and euhydrated states. After a rise at the onset of exercise, internal carotid artery flow declined to baseline with progressive dehydration (P < 0.05). However, cerebral metabolism remained stable through enhanced O2 and glucose extraction (P < 0.05). External carotid artery flow increased for 1 h but declined before exhaustion. Fluid ingestion maintained cerebral and extracranial perfusion throughout nonfatiguing exercise. During exhaustive exercise, however, euhydration delayed but did not prevent the decline in cerebral perfusion. In conclusion, during prolonged exercise in the heat, dehydration accelerates the decline in CBF without affecting CMRO2 and also restricts extracranial perfusion. Thus, fatigue is related to a reduction in CBF and extracranial perfusion rather than CMRO2 ., (Copyright © 2015 the American Physiological Society.)