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Background: The causal nature of the observed associations between serum lipids and apolipoproteins and kidney function are unclear.Methods: Using two-sample and multivariable Mendelian randomization (MR), we examined the causal effects of serum lipids and apolipoproteins on kidney function, indicated by the glomerular-filtration rate estimated using creatinine (eGFRcrea) or cystatin C (eGFRcys) and the urinary albumin-to-creatinine ratio (UACR). We obtained lipid- and apolipoprotein-associated genetic variants from the Global Lipids Genetics Consortium (n = 331 368) and UK Biobank (n = 441 016), respectively, and kidney-function markers from the Trøndelag Health Study (HUNT; n = 69 736) and UK Biobank (n = 464 207). The reverse causal direction was examined using variants associated with kidney-function markers selected from recent genome-wide association studies.Results: There were no strong associations between genetically predicted lipid and apolipoprotein levels with kidney-function markers. Some, but inconsistent, evidence suggested a weak association of higher genetically predicted atherogenic lipid levels [indicated by low-density lipoprotein cholesterol (LDL-C), triglycerides and apolipoprotein B] with increased eGFR and UACR. For high-density lipoprotein cholesterol (HDL-C), results differed between eGFRcrea and eGFRcys, but neither analysis suggested substantial effects. We found no clear evidence of a reverse causal effect of eGFR on lipid or apolipoprotein traits, but higher UACR was associated with higher LDL-C, triglyceride and apolipoprotein B levels.Conclusion: Our MR estimates suggest that serum lipid and apolipoprotein levels do not cause substantial changes in kidney function. A possible weak effect of higher atherogenic lipids on increased eGFR and UACR warrants further investigation. Processes leading to higher UACR may lead to more atherogenic lipid levels. [ABSTRACT FROM AUTHOR]

Context: Maternal lipids during pregnancy and placental growth factors are associated with excess fetal growth. However, how these factors interact to increase the risk of delivering large-for-gestational-age (LGA) neonates remains unclear. In this study, we investigated the relationship between maternal plasma triglycerides (TGs) and free fatty acids (FFAs) during pregnancy, cord blood insulin-like growth factors (IGF), and LGA.Objective: In a cell model, we studied the effect of different FAs on placental IGF-1 secretion.Methods: This cohort study included pregnant women with term pregnancy and without diabetes or hypertensive disorders in pregnancy. Maternal fasting plasma TGs and FFAs were measured in the second trimester. Cord blood IGF-1, IGF-2, and IGF binding protein-1 and protein-3 were measured at the time of delivery. A human trophoblast cell line, 3A-sub-E, was used to evaluate the effect of different FFAs on placental IGF-1 secretion.Results: We recruited 598 pregnant women-neonate pairs. Maternal plasma TG (180 mg/dL [152.5-185.5 mg/dL] vs 166 mg/dL [133-206 mg/dL], P = .04) and cord blood IGF-1 concentrations (72.7 ± 23.0 vs 54.1 ± 22.8 ng/mL, P < .001) were higher in the LGA group and were significantly associated with birth weight z score. Maternal plasma free palmitic acid (PA) and stearic acid (SA), but not oleic acid (OA) or linoleic acid (LA), were significantly associated with cord blood IGF-1 concentrations. In 3A-sub-E cells, treatment with PA, SA, and LA, but not OA, induced IGF-1 expression and secretion.Conclusion: Certain FFAs can induce placental IGF-1 secretion, which suggests a potential pathophysiology linking maternal plasma lipids and LGA. [ABSTRACT FROM AUTHOR]

Background: Age-related macular degeneration (AMD) is a leading cause of vision loss. Whereas lipids have been studied extensively to understand their effects on cardiovascular diseases, their relationship with AMD remains unclear.Methods: Two-sample Mendelian randomization (MR) analyses were performed to systematically evaluate the causal relationships between eight serum lipid biomarkers, consisting of apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), total cholesterol (CHOL), high-density lipoprotein cholesterol (HDL-C), direct low-density lipoprotein cholesterol (LDL-C), lipoprotein A [Lp(a)], triglycerides (TG) and non-HDL cholesterol (non-HDL-C), and the risk of different AMD stages and subtypes. We derived 64-407 genetic instruments for eight serum lipid biomarkers in 419 649 participants of European descent from the UK Biobank cohort. We conducted genome-wide association studies (GWAS) for 12 711 advanced AMD cases [8544 choroidal neovascularization (CNV) and 2656 geographic atrophy (GA) specific AMD subtypes] and 5336 intermediate AMD cases with 14 590 controls of European descent from the International AMD Genomics Consortium.Results: Higher genetically predicted HDL-C and ApoA1 levels increased the risk of all AMD subtypes. LDL-C, ApoB, CHOL and non-HDL-C levels were associated with decreased risk of intermediate and GA AMD but not with CNV. Genetically predicted TG levels were associated with decreased risk of different AMD subtypes. Sensitivity analyses revealed no evidence for directional pleiotropy effects. In our multivariable MR analyses, adjusting for the effects of correlated lipid biomarkers yielded similar results.Conclusion: These results suggest the role of lipid metabolism in drusen formation and particularly in AMD development at the early and intermediate stages. Mechanistic studies are warranted to investigate the utility of lipid pathways for therapeutic treatment in preventing AMD. [ABSTRACT FROM AUTHOR]

Context: Hyperthyroidism is associated with low levels of cholesterol and triglycerides, and hypothyroidism is associated with hypercholesterolemia and hypertriglyceridemia.Objective: The aim of this systematic review was to investigate the impact of therapy for overt and subclinical hyper- and hypothyroidism on serum lipids.Data Sources: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus from 1970 through April 5, 2018.Study Selection: Pairs of independent reviewers selected randomized and observational studies evaluating lipid parameters in patients undergoing treatment for hyper- or hypothyroidism.Data Extraction: Pairs of independent reviewers extracted data and appraised studies.Data Synthesis: Treatment of overt hyperthyroidism showed a significant increase in total cholesterol (TC) by 44.50 mg/dL (95% confidence interval [CI]: 37.99, 51.02), low-density lipoprotein cholesterol (LDL-C) by 31.13 mg/dL (95% CI: 24.33, 37.93), high-density lipoprotein cholesterol (HDL-C) by 5.52 mg/dL (95% CI: 1.48, 9.56), apolipoprotein A (Apo A) by 15.6 mg/dL (95% CI: 10.38, 20.81), apolipoprotein B (apo B) by 26.12 mg/dL (95% CI: 22.67, 29.57), and lipoprotein (Lp[a]) by 4.18 mg/dL (95% CI: 1.65, 6.71). There was no significant change in triglyceride (TG) levels. Treatment of subclinical hyperthyroidism did not change any lipid parameters significantly. Levothyroxine therapy in overt hypothyroidism showed a statistically significant decrease in TC by -58.4 mg/dL (95% CI: -64.70, -52.09), LDL-C by -41.11 mg/dL (95% CI: -46.53, -35.69), HDL-C by -4.14 mg/dL (95% CI: -5.67, -2.61), TGs by -7.25 mg/dL (95% CI: -36.63, 17.87), apo A by -12.59 mg/dL (95% CI: -17.98, -7.19), apo B by -33.96 mg/dL (95% CI: 41.14, -26.77), and Lp(a) by -5.6 mg/dL (95% CI: -9.06, -2.14). Levothyroxine therapy in subclinical hypothyroidism showed similar changes but with a smaller magnitude. The studies contained varied population characteristics, severity of thyroid dysfunction, and follow-up duration.Conclusions: Treatment of overt but not subclinical hyperthyroidism is associated with worsening of the lipid profile. Levothyroxine therapy in both overt and subclinical hypothyroidism leads to improvement in the lipid profile, with a smaller magnitude of improvement in subclinical hypothyroidism. [ABSTRACT FROM AUTHOR]

Background: Although high-density lipoprotein (HDL) and non-HDL cholesterol have opposite associations with coronary heart disease, multi-country reports of lipid trends only use total cholesterol (TC). Our aim was to compare trends in total, HDL and non-HDL cholesterol and the total-to-HDL cholesterol ratio in Asian and Western countries.Methods: We pooled 458 population-based studies with 82.1 million participants in 23 Asian and Western countries. We estimated changes in mean total, HDL and non-HDL cholesterol and mean total-to-HDL cholesterol ratio by country, sex and age group.Results: Since ∼1980, mean TC increased in Asian countries. In Japan and South Korea, the TC rise was due to rising HDL cholesterol, which increased by up to 0.17 mmol/L per decade in Japanese women; in China, it was due to rising non-HDL cholesterol. TC declined in Western countries, except in Polish men. The decline was largest in Finland and Norway, at ∼0.4 mmol/L per decade. The decline in TC in most Western countries was the net effect of an increase in HDL cholesterol and a decline in non-HDL cholesterol, with the HDL cholesterol increase largest in New Zealand and Switzerland. Mean total-to-HDL cholesterol ratio declined in Japan, South Korea and most Western countries, by as much as ∼0.7 per decade in Swiss men (equivalent to ∼26% decline in coronary heart disease risk per decade). The ratio increased in China.Conclusions: HDL cholesterol has risen and the total-to-HDL cholesterol ratio has declined in many Western countries, Japan and South Korea, with only a weak correlation with changes in TC or non-HDL cholesterol. [ABSTRACT FROM AUTHOR]

Blood lipids are causally involved in the pathogenesis of atherosclerosis, but their role in cerebral small vessel disease remains largely elusive. Here, we explored associations of genetic determinants of blood lipid levels, lipoprotein particle components, and targets for lipid-modifying drugs with small vessel disease phenotypes. We selected genetic instruments for blood levels of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides, for cholesterol and triglycerides components of size-defined lipoprotein particles, and for lipid-modifying drug targets based on published genome-wide association studies (up to 617 303 individuals). Applying two-sample Mendelian randomization approaches we investigated associations with ischaemic and haemorrhagic manifestations of small vessel disease [small vessel stroke: 11 710 cases, 287 067 controls; white matter hyperintensities (WMH): 10 597 individuals; intracerebral haemorrhage: 1545 cases, 1481 controls]. We applied the inverse-variance weighted method and multivariable Mendelian randomization as our main analytical approaches. Genetic predisposition to higher HDL-C levels was associated with lower risk of small vessel stroke [odds ratio (OR) per standard deviation = 0.85, 95% confidence interval (CI) = 0.78-0.92] and lower WMH volume (β = -0.07, 95% CI = -0.12 to -0.02), which in multivariable Mendelian randomization remained stable after adjustments for LDL-C and triglycerides. In analyses of lipoprotein particle components by size, we found these effects to be specific for cholesterol concentration in medium-sized high-density lipoprotein, and not large or extra-large high-density lipoprotein particles. Association estimates for intracerebral haemorrhage were negatively correlated with those for small vessel stroke and WMH volume across all lipid traits and lipoprotein particle components. HDL-C raising genetic variants in the gene locus of the target of CETP inhibitors were associated with lower risk of small vessel stroke (OR: 0.82, 95% CI = 0.75-0.89) and lower WMH volume (β = -0.08, 95% CI = -0.13 to -0.02), but a higher risk of intracerebral haemorrhage (OR: 1.64, 95% CI = 1.26-2.13). Genetic predisposition to higher HDL-C, specifically to cholesterol in medium-sized high-density lipoprotein particles, is associated with both a lower risk of small vessel stroke and lower WMH volume. These analyses indicate that HDL-C raising strategies could be considered for the prevention of ischaemic small vessel disease but the net benefit of such an approach would need to be tested in a randomized controlled trial. [ABSTRACT FROM AUTHOR]

Objectives: To analyse lipid changes and tolerability in a cohort of HIV-infected patients who switched their antiretroviral regimens to rilpivirine/emtricitabine/tenofovir (RPV/FTC/TDF) in a real-world setting.Methods: PRO-STR is a 48 week prospective observational post-authorization study in 25 hospitals. Patients with a viral load <1000 copies/mL, receiving at least 12 months of combination ART (cART), with constant posology for at least the prior 3 months, were categorized according to previous treatment [NNRTI or ritonavir-boosted PI (PI/r)]. Analytical tests were performed at the baseline visit, between week 16 and week 32, and at week 48.Results: A total of 303 patients were included (mean age 46.6 years; male 74.0%; previous treatment 74.7% NNRTI and 25.3% PI/r). Both groups exhibited significantly reduced lipid profiles, except for HDL cholesterol, for which a non-significant increase was observed. [NNRTI patients: total cholesterol (baseline: 195.5 ± 38.4 mg/dL; week 48: 171.0 ± 35.5 mg/dL), total cholesterol/HDL ratio (baseline: 4.2 ± 1.2; week 48: 4.0 ± 1.2), HDL (baseline: 49.1 ± 12.0 mg/dL; week 48: 49.2 ± 45.8 mg/dL), LDL (baseline: 119.2 ± 30.2 mg/dL; week 48: 114.2 ± 110.7 mg/dL), and triglycerides (baseline: 136.6 ± 86.8 mg/dL; week 48: 113.4 ± 67.8 mg/dL); PI/r patients: total cholesterol (baseline: 203.2 ± 48.8 mg/dL; week 48: 173.4 ± 36.9 mg/dL), total cholesterol/HDL ratio (baseline: 4.7 ± 1.6; week 48: 4.0 ± 1.2), HDL (baseline: 46.4 ± 12.5 mg/dL; week 48: 52.1 ± 54.4 mg/dL), LDL (baseline: 127.0 ± 36.3 mg/dL; week 48: 111.4 ± 35.8 mg/dL), and triglycerides (baseline: 167.6 ± 107.7 mg/dL; week 48: 122.7 ± 72.1 mg/dL)]. The most common intolerances were neuropsychiatric in the NNRTI patients and gastrointestinal and metabolic in the PI/r patients, and these intolerances were significantly reduced in both groups at week 48 [NNRTI: neuropsychiatric (baseline: 81.3%; week 48: 0.0%); PI/r: gastrointestinal (baseline: 48.7%; week 48: 0.0%) and metabolic (baseline: 42.1%; week 48: 0.0%)].Conclusions: RPV/FTC/TDF improved the lipid profiles and reduced the intolerances after switching from NNRTI or PI-based regimens, in a cohort of HIV-infected patients. [ABSTRACT FROM AUTHOR]

Study Question: Are maternal preconception lipid levels associated with fecundability?Summary Answer: Fecundability was reduced for all abnormal female lipid levels including total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and total triglyceride levels.What Is Known Already: Subfecundity affects 7-15% of the population and lipid disorders are hypothesized to play a role since cholesterol acts as a substrate for the synthesis of steroid hormones. Evidence illustrating this relationship at the mechanistic level is mounting but few studies in humans have explored the role of preconception lipids in fecundity.Study Design, Size, Duration: A secondary analysis of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial (2007-2011), a block-randomized, double-blind, placebo-controlled trial.Participants/materials, Setting, Methods: A total of 1228 women, with 1-2 prior pregnancy losses and without a diagnosis of infertility, attempting pregnancy for up to six menstrual cycles were recruited from clinical sites in Utah, New York, PA and Colorado. Time to pregnancy was the number of menstrual cycles to pregnancy as determined by positive hCG test or ultrasound. Individual preconception lipoproteins were measured at baseline, prior to treatment randomization and dichotomized based on clinically accepted cut-points as total cholesterol ≥200 mg/dl, LDL-C ≥130 mg/dl, HDL-C <50 mg/dl and triglycerides ≥150 mg/dl.Main Results and the Role Of Chance: There were 148 (12.3%) women with elevated total cholesterol, 94 (7.9%) with elevated LDL-C, 280 (23.2%) with elevated triglycerides and 606 (50.7%) with low HDL-C. The fecundability odds ratio (FOR) was reduced for all abnormal lipids before and after confounder adjustment, indicating reduced fecundability. Total cholesterol ≥200 mg/dl was associated with 24% (FOR: 0.76, 95% CI: 0.59, 0.97) and 29% (FOR: 0.71, 95% CI: 0.55, 0.93) reduced fecundability for hCG-detected and ultrasound-confirmed pregnancy, respectively, compared with total cholesterol <200 mg/dl. There was a 19-36% decrease in the probability of conception per cycle for women with abnormal lipoprotein levels, though additional adjustment for central adiposity and BMI attenuated observed associations.Limitations, Reasons For Caution: Although the FOR is a measure of couple fecundability, we had only measures of female lipid levels and can therefore not confirm the findings from a previous study indicating the independent role of male lipids in fecundity. The attenuated estimates and decreased precision after adjustment for central adiposity and obesity indicate the complexity of potential causal lipid pathways, suggesting other factors related to obesity besides dyslipidemia likely contribute to reduced fecundability.Wider Implications Of the Findings: Our results are consistent with one other study relating preconception lipid concentrations to fecundity and expand these findings by adding critically important information about individual lipoproteins. As lipid levels are modifiable they may offer an inexpensive target to improve female fecundability.Study Funding and Competing Interest(s): This study was funded by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors have declared that no conflicts of interest exist.Trial Registration Number: #NCT00467363. [ABSTRACT FROM AUTHOR]

Caloric restriction (CR), which increases longevity and retards age-associated diseases in laboratory rodents, is being evaluated in nonhuman primate trials. CR reduces oxidative stress in rodents and appears to improve risk factors for cardiovascular disease in nonhuman primates. We tested the hypothesis that low-density lipoprotein (LDL) oxidizability is reduced in two monkey species (rhesus and cynomolgus) subjected to chronic CR. In both species, no significant differences occurred between CR and control animals on total, LDL, or high-density lipoprotein (HDL) cholesterol. In rhesus monkeys, triglycerides were higher in controls than CR (139 +/- 23 vs 66 +/- 8 mg/dl,p < .01, respectively). LDL from CR rhesus monkeys was reduced in triglyceride content and molecular weight compared to controls, whereas LDL composition in cynomolgus monkeys was similar in CR and control animals. In keeping with minor deviations in lipids, antioxidants, and LDL composition, no consistent differences in in vitro LDL oxidizability were apparent between CR and controls in either species. [ABSTRACT FROM AUTHOR]