Low-density lipoprotein size and cardiovascular risk assessment

A predominance of small, dense low-density lipoproteins (LDL) has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart disease and evidences suggests that both quality (particularly small, dense LDL) and quantity may increase cardiovascular risk. However, other authors have suggested that LDL size measurement does not add information beyond that obtained by measuring LDL concentration, triglyceride levels and HDL concentrations. Therefore, it remains debatable whether to measure LDL particle size in cardiovascular risk assessment and, if so, in which categories of patient. Therapeutic modulation of LDL particle size or number appears beneficial in reducing the risk of cardiovascular events, but no clear causal relationship has been shown, because of confounding factors, including lipid and non-lipid variables. Studies are needed to investigate the clinical significance of LDL size measurements in patients with coronary and non-coronary forms of atherosclerosis; in particular, to test whether LDL size is associated with even higher vascular risk, and whether LDL size modification may contribute to secondary prevention in such patient

Glucose lowering and anti-atherogenic effects of incretin-based therapies: GLP-1 analogues and DPP-4-inhibitors

BACKGROUND: Type 2 diabetes is a chronic, progressive disease with a multi-faceted pathophysiology. Beyond the known defects of insulin resistance and beta-cell insufficiency, derangement of incretin hormones normally produced from the gut wall in response to food intake play an important role. In recent years, the 'incretin-based' therapies (IBTs) have been developed to address hyperglycemia through either mimicking the action of the endogenous incretin glucagon-like polypeptide (GLP-1) (GLP-1 receptor agonists) or by inhibiting the activity of the enzyme that degrades GLP-1 (the dipeptyl peptidase-4 inhibitors). OBJECTIVE: We reviewed available evidence on the glucose lowering and anti-atherogenic effects of IBT. RESULTS: In addition to their glucose-lowering and weight-neutral or weight-reducing actions, IBT decrease systolic blood pressure and improve fasting and postprandial lipid parameters by reducing total-cholesterol, low-density lipoprotein-cholesterol and triglycerides concentrations, and increasing high-density lipoprotein-cholesterol values. Reduced high-sensitivity C-reactive protein levels and improved endothelial dysfunction have been reported too. CONCLUSIONS: IBT have several beneficial effects on cardiovascular risk factors and, for this reason, it has been recently suggested to extend the use of these drugs in diabetic patients with cardiovascular complications. Yet, the long-term effects of IBT on subclinical or clinical atherosclerosis remain to be established by future studies

Ezetimibe alone or in combination with simvastatin increases small dense low-density lipoproteins in healthy men: a randomized trial

Aims The predominance of small dense low-density lipoproteins (sdLDLs) has been associated with increased cardiovascular risk. The effect of ezetimibe on LDL subfraction distribution has not been fully elucidated. This study assessed by gradient gel electrophoresis the effects of ezetimibe alone, simvastatin alone, and their combination on sdLDL subfraction distribution. Methods and results A single-centre, randomized, parallel three-group open-label study was performed in 72 healthy men with a baseline LDL-cholesterol (LDL-C) concentration of 111 ± 30 mg/dL (2.9 ± 0.8 mmol/L). They were treated with ezetimibe (10 mg/day, n = 24), simvastatin (40 mg/day, n = 24), or their combination (n = 24) for 14 days. Blood was drawn before and after the treatment period. Generalized estimating equations were used to assess the influence of drug therapy on LDL subfraction distribution, controlling for within-subject patterns (clustering). We adjusted for age, body mass index, and baseline concentrations of LDL-C and triglycerides. Ezetimibe alone changed LDL subfraction distribution towards a more atherogenic profile by significantly increasing sdLDL subfractions (LDL-IVA +14.2%, P = 0.0216 and LDL-IVB +16.7%, P = 0.039; fully adjusted Wald χ2 test). In contrast, simvastatin alone significantly decreased the LDL-IVB subfraction (−16.7%, P = 0.002). This effect was offset when simvastatin was combined with ezetimibe (LDL-IVB +14.3%, P = 0.44). All three treatments decreased the large, more buoyant LDL-I subfraction, the effects of ezetimibe being the most pronounced (ezetimibe -13.9%, P < 0.0001; combination therapy −7.3%, P = 0.0743; simvastatin −4.6%, P < 0.0001). Conclusion In healthy men, treatment with ezetimibe alone is associated with the development of a pro-atherogenic LDL subfraction profile. Potentially atheroprotective effects of simvastatin are offset by ezetimibe. This study is registered with ClinicalTrials.gov, identifier no. NCT0031799

Milder forms of atherogenic dyslipidemia in ovulatory versus anovulatory polycystic ovary syndrome phenotype

BACKGROUND Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) but its prevalence in different PCOS phenotypes is still largely unknown. METHODS We measured plasma lipids and lipoproteins in 35 anovulatory PCOS (age: 25 ± 6 years, BMI: 28 ± 6 kg/m2), 15 ovulatory PCOS (age: 30 ± 6 years, BMI: 25 ± 3 kg/m2) and 27 healthy women (controls) age- and BMI-matched with ovulatory PCOS. PCOS was diagnosed by the presence of clinical or biologic hyperandrogenism associated with chronic anovulation and/or polycystic ovaries at ultrasound. In women with normal menses chronic anovulation was indicated by low serum progesterone levels (<9.54 nmol/l) during midluteal phase (days 21-24) in two consecutive menstrual cycles. RESULTS Total cholesterol, triglycerides and low-density lipoprotein (LDL)-cholesterol levels increased and high-density lipoprotein (HDL)-cholesterol decreased from controls to ovulatory and then to anovulatory PCOS (all P < 0.05). Levels of lipoprotein(a) (Lp(a)) and small, dense LDL increased (P < 0.0001 for both) and LDL size reduced (P < 0.005) between groups. Insulin resistance (by HOMA) showed a positive correlation with triglycerides and small, dense LDL and an inverse correlation with HDL-cholesterol and LDL size (P < 0.05 for all) in both PCOS phenotypes. No significant correlations were found with testosterone levels. At multivariate analysis, insulin resistance was independently associated with HDL-cholesterol and small, dense LDL in both PCOS phenotypes and with triglyceride concentrations in ovulatory PCOS only. CONCLUSIONS Women with ovulatory PCOS showed milder forms of atherogenic dyslipidemia than anovulatory PCOS and this seemed to be related to the extent of insulin resistance. Future prospective studies are needed to assess the relative contribution of such alterations on cardiovascular ris

Disturbed eating at high altitude: influence of food preferences, acute mountain sickness and satiation hormones

Purpose: Hypoxia has been shown to reduce energy intake and lead to weight loss, but the underlying mechanisms are unclear. The aim was therefore to assess changes in eating after rapid ascent to 4,559m and to investigate to what extent hypoxia, acute mountain sickness (AMS), food preferences and satiation hormones influence eating behavior. Methods: Participants (n=23) were studied at near sea level (Zurich (ZH), 446m) and on two days after rapid ascent to Capanna Margherita (MG) at 4,559m (MG2 and MG4). Changes in appetite, food preferences and energy intake in an ad libitum meal were assessed. Plasma concentrations of cholecystokinin, peptide tyrosine-tyrosine, gastrin, glucagon and amylin were measured. Peripheral oxygen saturation (SpO2) was monitored, and AMS assessed using the Lake Louis score. Results: Energy intake from the ad libitum meal was reduced on MG2 compared to ZH (643±308 vs. 952±458kcal, p=0.001), but was similar to ZH on MG4 (890±298kcal). Energy intake on all test days was correlated with hunger/satiety scores prior to the meal and AMS scores on MG2 but not with SpO2 on any of the 3days. Liking for high-fat foods before a meal predicted subsequent energy intake on all days. None of the satiation hormones showed significant differences between the 3days. Conclusion: Reduced energy intake after rapid ascent to high altitude is associated with AMS severity. This effect was not directly associated with hypoxia or changes in gastrointestinal hormones. Other peripheral and central factors appear to reduce food intake at high altitud

Insights from interviews with German supply chain managers: a study of supply chain transformations and emerging issues

To investigate current trends and challenges related to supply chain management in Germany, we conduct an interview-based study involving 16 experts. The study focuses on three areas: supply chain transformations, software challenges, and the adoption of emerging technologies. Supply chain transformations are influenced by increasing supply chain complexity, the growing prevalence of e-commerce, and the increased importance allocated by customers to trust and transparency. Complexity is, in part, due to disruptions caused by policy responses to the pandemic and to software challenges in terms of the adaptability of ERP systems and the cybersecurity of cloud-based solutions. This study is relevant for practitioners, as it sheds light on pressing issues in supply chain management, and for researchers as it uncovers potential topics that require further research in the future

Milk and dairy products: good or bad for human health? An assessment of the totality of scientific evidence

Background: There is scepticism about health effects of dairy products in the public, which is reflected in an increasing intake of plant-based drinks, for example, from soy, rice, almond, or oat. Objective: This review aimed to assess the scientific evidence mainly from meta-analyses of observational studies and randomised controlled trials, on dairy intake and risk of obesity, type 2 diabetes, cardiovascular disease, osteoporosis, cancer, and all-cause mortality. Results: The most recent evidence suggested that intake of milk and dairy products was associated with reduced risk of childhood obesity. In adults, intake of dairy products was shown to improve body composition and facilitate weight loss during energy restriction. In addition, intake of milk and dairy products was associated with a neutral or reduced risk of type 2 diabetes and a reduced risk of cardiovascular disease, particularly stroke. Furthermore, the evidence suggested a beneficial effect of milk and dairy intake on bone mineral density but no association with risk of bone fracture. Among cancers, milk and dairy intake was inversely associated with colorectal cancer, bladder cancer, gastric cancer, and breast cancer, and not associated with risk of pancreatic cancer, ovarian cancer, or lung cancer,while the evidence for prostate cancer risk was inconsistent.Finally,consumption of milk and dairy products was not associated with all-cause mortality. Calcium-fortified plant-based drinks have been included as an alternative to dairy products in the nutrition recommendations in several countries. However, nutritionally, cow’s milk and plant-based drinks are completely different foods,and an evidence-based conclusion on the health value of the plant-based drinks requires more studies in humans. Conclusion: The totality of available scientific evidence supports that intake of milk and dairy products contribute to meet nutrient recommendations, and may protect against the most prevalent chronic diseases, whereas very few adverse effects have been reported