Association of blood lipid profile with incident chronic kidney disease: A Mendelian randomization study.

Cohort studies found blood lipid traits were associated with the risk of chronic kidney disease (CKD). We aimed to investigate whether blood lipid traits were causally associated with the risk of CKD in the Chinese. 15,244 participants without kidney disease and cancer from the Dongfeng-Tongji cohort were recruited in 2008-2010 in Shiyan City, China. Blood total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), and triglyceride (TG) levels were measured. 5251 participants had genotype data and were included in the Mendelian randomization analysis. Incident CKD was defined as estimated glomerular filtration rate <60 ml/min per 1.73 m2 in 2013. Logistic regression and Mendelian randomization methods were used to estimate the observed and causal associations of blood lipid traits with incident CKD. Various blood lipid traits were associated with CKD risk, and the odds ratios (95% confidence intervals) for incident CKD comparing the extreme quartiles were 1.45 (1.24-1.70) for TG, 1.26 (1.08-1.46) for nonHDL-c, 2.21 (1.91-2.57) for TC:HDL-c ratio, 2.14 (1.83-2.51) for TG:HDL-c ratio, and 0.47 (0.40-0.55) for HDL-c. The Mendelian randomization analysis indicated that 1 mmol/l increase in the genetic predicted blood TG level was associated with a 5% (95% confidence interval, 0-10%) higher risk of CKD. Although blood levels of HDL-c, TG, nonHDL-c, TC:HDL-c ratio, and TG:HDL-c ratio were observed to be associated with incident CKD, the Mendelian randomization analysis provided genetic evidence to support causal relation for blood TG level only.

Zhang YB ，Sheng LT ，Wei W ，Guo H ，Yang H ，Min X ，Guo K ，Yang K ，Zhang X ，He M ，Wu T ，Pan A ... -  《-》

HDL Cholesterol, LDL Cholesterol, and Triglycerides as Risk Factors for CKD: A Mendelian Randomization Study.

High-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride concentrations are heritable risk factors for vascular disease, but their role in the progression of chronic kidney disease (CKD) is unclear. 2-sample Mendelian randomization analysis of data derived from the largest published lipid and CKD studies. Effect of independent genetic variants significantly associated with lipid concentrations was obtained from the Global Lipids Genetics Consortium (n=188,577), and the effect of these same variants on estimated glomerular filtration rate (eGFR), CKD (defined as eGFR<60mL/min/1.73m2), and albuminuria was obtained from the CKD Genetics Consortium (n=133,814). Using conventional, multivariable, and Egger Mendelian randomization approaches, we assessed the causal association between genetically determined lipid concentrations and kidney traits. eGFR, dichotomous eGFR<60mL/min/1.73m2, and albuminuria. In multivariable analysis, a 17-mg/dL higher HDL cholesterol concentration was associated with an 0.8% higher eGFR (95% CI, 0.4%-1.3%; P=0.004) and lower risk for eGFR<60mL/min/1.73m2 (OR, 0.85; 95% CI, 0.77-0.93; P<0.001), while Egger analysis showed no evidence of pleiotropy. There was no evidence for a causal relationship between LDL cholesterol concentration and any kidney disease measure. Genetically higher triglyceride concentrations appeared associated with higher eGFRs, but this finding was driven by a single pleiotropic variant in the glucokinase regulator gene (GCKR). After exclusion, genetically higher triglyceride concentration was not associated with any kidney trait. Individual patient-level phenotype and genotype information were unavailable. 2-sample Mendelian randomization analysis of data from the largest lipid and CKD cohorts supports genetically higher HDL cholesterol concentration as causally associated with better kidney function. There was no association between genetically altered LDL cholesterol or triglyceride concentration and kidney function. Further analysis of CKD outcomes in HDL cholesterol intervention trials is warranted.

Lanktree MB ，Thériault S ，Walsh M ，Paré G ... -  《-》

Causal effect between total cholesterol and HDL cholesterol as risk factors for chronic kidney disease: a mendelian randomization study.

Miao L ，Min Y ，Qi B ，Zhu CM ，Chen JH ，Deng GX ，Wang Y ，Li JF ，Li RS ... -  《BMC Nephrology》

Apolipoprotein B, Triglyceride-Rich Lipoproteins, and Risk of Cardiovascular Events in Persons with CKD.

Triglyceride-rich lipoproteins may contribute to the high cardiovascular risk of patients with CKD. This study evaluated associations of apo-B and markers of triglyceride-rich lipoproteins with cardiovascular events in people with CKD. Analyses were conducted in 9270 participants with CKD in the Study of Heart and Renal Protection (SHARP): 6245 not on dialysis (mean eGFR 26.5 ml/min per 1.73 m2), and 3025 on dialysis when recruited. Cox regression methods were used to evaluate associations of lipids with incident atherosclerotic and nonatherosclerotic vascular events, adjusting for demographics and clinical characteristics. Hazard ratios (HRs) were calculated per 1 SD higher level for apo-B, HDL cholesterol, LDL cholesterol, triglyceride-rich lipoprotein cholesterol (i.e., total cholesterol minus LDL cholesterol minus HDL cholesterol), non-HDL cholesterol, log triglyceride, and log ratio of triglyceride to HDL cholesterol. During a median follow-up of 4.9 years (interquartile range, 4.0-5.5 years), 1406 participants experienced at least one atherosclerotic vascular event. In multivariable adjusted models, positive associations with atherosclerotic vascular events were observed for apo-B (HR per 1 SD, 1.19; 95% confidence interval, 1.12 to 1.27), triglycerides (1.06; 1.00 to 1.13), the ratio of triglyceride to HDL cholesterol (1.10; 1.03 to 1.18), and triglyceride-rich lipoprotein cholesterol (1.14; 1.05 to 1.25). By contrast, inverse associations with nonatherosclerotic vascular events were observed for each of these lipid markers: apo-B (HR per 1 SD, 0.92; 0.85 to 0.98), triglycerides (0.86; 0.81 to 0.92), the ratio of triglyceride to HDL cholesterol (0.88; 0.82 to 0.94), and triglyceride-rich lipoprotein cholesterol (0.85; 0.77 to 0.94). Higher apo-B, triglycerides, ratio of triglyceride to HDL cholesterol, and triglyceride-rich lipoprotein cholesterol concentrations were associated with increased risk of atherosclerotic vascular events in CKD. Reducing triglyceride-rich lipoproteins using novel therapeutic agents could potentially lower the risk of atherosclerotic cardiovascular disease risk in the CKD population.

Lamprea-Montealegre JA ，Staplin N ，Herrington WG ，Haynes R ，Emberson J ，Baigent C ，de Boer IH ，SHARP Collaborative Group ... -  《-》

The causal effects of lipid traits on kidney function in Africans: bidirectional and multivariable Mendelian-randomization study.

Observational studies have investigated the effect of serum lipids on kidney function, but these findings are limited by confounding, reverse causation and have reported conflicting results. Mendelian randomization (MR) studies address this confounding problem. However, they have been conducted mostly in European ancestry individuals. We, therefore, set out to investigate the effect of lipid traits on the estimated glomerular filtration rate (eGFR) based on serum creatinine in individuals of African ancestry. We used the two-sample and multivariable Mendelian randomization (MVMR) approaches; in which instrument variables (IV's) for the predictor (lipid traits) were derived from summary-level data of a meta-analyzed African lipid GWAS (MALG, n = 24,215) from the African Partnership for Chronic Disease Research (APCDR) (n = 13,612) & the Africa Wits-IN-DEPTH partnership for Genomics studies (AWI-Gen) dataset (n = 10,603). The outcome IV's were computed from the eGFR summary-level data of African-ancestry individuals within the Million Veteran Program (n = 57,336). A random-effects inverse variance method was used in our primary analysis, and pleiotropy was adjusted for using robust and penalized sensitivity testing. The lipid predictors for the MVMR were high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides (TG). We found a significant causal association between genetically predicted low-density lipoprotein (LDL) cholesterol and eGFR in African ancestry individuals β = 1.1 (95% CI [0.411-1.788]; p = 0.002). Similarly, total cholesterol (TC) showed a significant causal effect on eGFR β = 1.619 (95% CI [0.412-2.826]; p = 0.009). However, the IVW estimate showed that genetically predicted HDL-C β = -0.164, (95% CI = [-1.329 to 1.00]; p = 0.782), and TG β = -0.934 (CI = [-2.815 to 0.947]; p = 0.33) were not significantly causally associated with the risk of eGFR. In the multivariable analysis inverse-variance weighted (MVIVW) method, there was evidence for a causal association between LDL and eGFR β = 1.228 (CI = [0.477-1.979]; p = 0.001). A significant causal effect of Triglycerides (TG) on eGFR in the MVIVW analysis β = -1.3 ([-2.533 to -0.067]; p = 0.039) was observed as well. All the causal estimates reported reflect a unit change in the outcome per a 1 SD increase in the exposure. HDL showed no evidence of a significant causal association with eGFR in the MVIVW method (β = -0.117 (95% CI [-1.252 to 0.018]; p = 0.840)). We found no evidence of a reverse causal impact of eGFR on serum lipids. All our sensitivity analyses indicated no strong evidence of pleiotropy or heterogeneity between our instrumental variables for both the forward and reverse MR analysis. In this African ancestry population, genetically predicted higher LDL-C and TC are causally associated with higher eGFR levels, which may suggest that the relationship between LDL, TC and kidney function may be U-shaped. And as such, lowering LDL_C does not necessarily improve risk of kidney disease. This may also imply the reason why LDL_C is seen to be a poorer predictor of kidney function compared to HDL. In addition, this further supports that more work is warranted to confirm the potential association between lipid traits and risk of kidney disease in individuals of African Ancestry. Wellcome (220740/Z/20/Z).

Kintu C ，Soremekun O ，Kamiza AB ，Kalungi A ，Mayanja R ，Kalyesubula R ，Bagaya S B ，Jjingo D ，Fabian J ，Gill D ，Nyirenda M ，Nitsch D ，Chikowore T ，Fatumo S ... -  《EBioMedicine》