Early Life Microcirculatory Plasticity and Blood Pressure Changes in Low Birth Weight Infants Born to Normotensive Mothers: A Cohort Study.

BACKGROUND: Capillary rarefaction (CR) is an established hallmark of essential hypertension (EH). The aim of this study was to examine early changes in capillary density (CD) and blood pressure (BP) in low birth weight (LBW) infants who are at risk of developing EH in later life. METHODS: We studied 77 LBW infants and 284 normal birth weight (NBW) infants, all born to mothers with normotension, in a longitudinal multicenter study. Intravital capillaroscopy was used to measure functional basal capillary density (BCD) and maximal capillary density (MCD) at birth, 3, 6, and 12 months. RESULTS: We found that LBW infants, born preterm and at term, had a significantly higher CD at birth, then underwent significant CR in the 1st 3 months culminating in a CD similar to that seen in NBW infants. NBW infants showed a gradual reduction in CD between birth and 12 months. Non-Caucasian ethnicity and preterm birth were significant predictors of a higher CD at birth. Systolic BP in NBW infants increased significantly from birth to 3 months, and we identified a significant negative correlation between systolic BP and MCD. CONCLUSIONS: This study has identified a process of early "accelerated capillary remodeling" in LBW infants, which corrects their higher CD at birth. This remodeling is unlikely to explain the CR seen in adult individuals with, or at risk of developing EH. Further follow-up studies are required to determine the timing and mechanisms involved in CR, which is likely to occur after the 1st year of life but before early adulthood

Late effects of hypertensive disorders of pregnancy on central blood pressure, microcirculation and cardiovascular disease: a cross-sectional case control study

Objective: The Inter-arm blood Pressure difference Individual Patient Data (INTERPRESS-IPD) Collaboration recently demonstrated, based on data from over 57,000 records, that an inter-arm difference in systolic blood pressure (IAD) is an independent risk marker for cardiovascular events after adjustment for Framingham or QRISK2 scores. This approach offers improved risk prediction through reclassification of individuals across risk categories and can result in initiation of treatment for primary prevention of cardiovascular disease in those close to current pharmaceutical intervention thresholds. The aim of this study was to model this approach of adjusting cardiovascular risk prediction scores for IAD in a typical primary care population. Design and method: Individuals aged 45–75 years, free of cardiovascular disease, had bilateral blood pressure measured three times, simultaneously, during National Health Service (NHS) Health Checks in one rural general practice in Devon, England. QRISK2 scores were calculated as part of the Health Check process, Framingham risk scores were calculated during analysis with Stata v15.0. Framingham and QRISK2 risk scores were adjusted by taking account of hazard ratios for IAD derived from our INTERPRESS-IPD analyses. Results: Complete data existed for 334 participants [mean (standard deviation): age 57.4 (9.3), systolic/diastolic blood pressure 132 (14)/79 (8.5)]. Mean Framingham and QRISK2 scores were 10.7 (8.1) and 8.0 (6.9), respectively before adjustment for IAD, and 11.1 (8.5) and 8.2 (7.1) afterwards (see figure). Overall, 10 (3%) participants were reclassified from below to above either the 10% or 20% Framingham risk thresholds, and 2 (1%) individuals were reclassified across the corresponding QRISK2 thresholds. For individuals with initial risk scores of 8% to 9.9%, 7/38 (18%) were reclassified to a Framingham risk above 10% and 2/35 (6%) to a QRISK2 score above 10%. Conclusions: Our findings confirm that systolic IADs can be applied to refine cardiovascular risk estimates in a UK primary care population. By taking account of systolic IAD, individual decisions on interventions for primary prevention of cardiovascular disease can be personalised, and could facilitate targeting of treatment to those at greater than average cardiovascular risk

Early life microcirculatory plasticity and blood pressure changes in low birth weight infants born to normotensive mothers: a cohort study

BACKGROUND Capillary rarefaction (CR) is an established hallmark of essential hypertension (EH). The aim of this study was to examine early changes in capillary density (CD) and blood pressure (BP) in low birth weight (LBW) infants who are at risk of developing EH in later life. METHODS We studied 77 LBW infants and 284 normal birth weight (NBW) infants, all born to mothers with normotension, in a longitudinal multicenter study. Intravital capillaroscopy was used to measure functional basal capillary density (BCD) and maximal capillary density (MCD) at birth, 3, 6, and 12 months. RESULTS We found that LBW infants, born preterm and at term, had a significantly higher CD at birth, then underwent significant CR in the 1st 3 months culminating in a CD similar to that seen in NBW infants. NBW infants showed a gradual reduction in CD between birth and 12 months. Non-Caucasian ethnicity and preterm birth were significant predictors of a higher CD at birth. Systolic BP in NBW infants increased significantly from birth to 3 months, and we identified a significant negative correlation between systolic BP and MCD. CONCLUSIONS This study has identified a process of early “accelerated capillary remodeling” in LBW infants, which corrects their higher CD at birth. This remodeling is unlikely to explain the CR seen in adult individuals with, or at risk of developing EH. Further follow-up studies are required to determine the timing and mechanisms involved in CR, which is likely to occur after the 1st year of life but before early adulthood