In humans, adaptive optics camera enables precise large-scale noninvasive retinal microcirculation evaluation to assess ageing, blood pressure and antihypertensive treatments respective roles on retinal arterioles anatomy. We used adaptive optics camera rtx1 (Imagine-Eyes, Orsay, France) to measure wall thickness, internal diameter and to calculate wall-to-lumen ratio (WLR) and wall cross-sectional area of retinal arterioles. This assessment was repeated within a short period in two subgroups of hypertensive individuals without or with a drug-induced blood pressure drop. In 1000 individuals, mean wall thickness, lumen diameter and WLR were 23.2 ± 3.9, 78.0 ± 10.9 and 0.300 ± 0.054 μm, respectively. Blood pressure and age both independently increased WLR by thickening arterial wall. In opposite, hypertension narrowed lumen in younger as compared to older individuals (73.2 ± 9.0 vs. 81.7 ± 10.2 μm; P < 0.001), whereas age exerted no influence on lumen diameter. Short-term blood pressure drop (-29.3 ± 17.3/-14.4 ± 10.0 mmHg) induced a WLR decrease (-6.0 ± 8.0%) because of lumen dilatation (+4.4 ± 5.9%) without wall thickness changes. By contrast, no modifications were observed in individuals with stable blood pressure. In treated and controlled hypertensives under monotherapy WLR normalization was observed because of combined wall decrease and lumen dilatation independently of antihypertensive pharmacological classes. In multivariate analysis, hypertension drug regimen was not an independent predictor of any retinal anatomical indices. Retinal arteriolar remodeling comprised blood pressure and age-driven wall thickening as well as blood pressure-triggered lumen narrowing in younger individuals. Remodeling reversal observed in controlled hypertensives seems to include short-term functional and long-term structural changes.
18 June 2020 in Diabetes/Metabolism Research and Reviews
Structural and functional dysfunction in both the macro- and microvasculature are a feature of essential hypertension. In a healthy cardiovascular system, the elastic properties of the large arteries ensure that pulsations in pressure and flow generated by cyclic left ventricular contraction are dampened, so that less pulsatile pressure and flow are delivered at the microvascular level. However, in response to aging, hypertension, and other disease states, arterial stiffening limits the buffering capacity of the elastic arteries, thus exposing the microvasculature to increased pulsatile stress. This is thought to be particularly pertinent to high flow/low resistance organs such as the brain and kidney, which may be sensitive to excess pressure and flow pulsatility, damaging capillary networks, and resulting in target organ damage. In this review, we describe the clinical relevance of the pulsatile interaction between the macro- and microvasculature and summarize current methods for measuring the transmission of pulsatility between the two sites.
A wealth of data demonstrates a causal link between serum low-density lipoprotein cholesterol (LDL-C) concentrations and cardiovascular disease (CVD). Any decrease in serum LDL-C concentrations is associated with a decreased CVD risk, and this benefit is similar to a comparable LDL-C reduction after drug treatment and dietary intervention. Moreover, life-long reductions in serum LDL-C levels have a large impact on CVD risk and a long-term dietary enrichment with functional foods or supplements with a proven LDL lowering efficacy is therefore a feasible and efficient approach to decrease future CVD risk. Functional foods with an LDL-C lowering effect can improve health and/or a reduce the risk of disease. However, it has not been mentioned specifically whether this concerns mainly universal prevention or whether this can also be applied to the hierarchy towards care related prevention. Therefore, we here describe the effects of a list of interesting functional food ingredients with proven benefit in LDL-C lowering. In addition, we pay particular attention to the emerging evidence that the addition of these functional ingredients and supplements is advisable as universal and selective prevention in the general population. Moreover, functional ingredients and supplements are also helpful in care related prevention, i.e. in patients with elevated LDL-C concentrations who are statin-intolerant or are not able to achieve their LDL-C target levels. Furthermore, we will highlight practical aspects regarding the use of functional foods with an LDL-C lowering effect, such as the increasing importance of shared decision making of medical doctors and dieticians with patients to ensure proper empowerment and better adherence to dietary approaches. In addition, we will address costs issues related to the use of these functional foods, which might be a barrier in some populations.