Causality of Genetically Determined Metabolites on Chronic Kidney Disease: A Two-Sample Mendelian Randomization Study In Silico

Introduction: Chronic kidney disease (CKD) is associated with metabolic disorders. However, the evidence for the causality of circulating metabolites to promote or prevent CKD is still lacking. Methods: The two-sample Mendelian randomization (MR) analysis was conducted to evaluate the latent causal relationship between the genetically proxied 486 blood metabolites and CKD. Genome-wide association study (GWAS) data for exposures were derived from 7824 European GWAS on metabolite levels, which have been extensively utilized in the medical field to elucidate the mechanisms underlying disease onset and progression. The random inverse variance weighted (IVW) is the primary analysis for causality analysis while MR-Egger and weighted median as complementary analyses. For the further identification of metabolites, reverse MR and linkage disequilibrium score regression were performed for further evaluation. The drug target for N-acetylornithine was subsequently supplemented into the analysis, with MR and colocalization analysis being utilized. Key metabolic pathways were identified via MetaboAnalyst 4.0 (https://www.metaboanalyst.ca/) online website. Results: N-acetylornithine was identified as a reliable metabolite that increases the susceptibility to estimated glomerular filtration rate (eGFR) decrease (β = 0.047; 95% confidence interval: -0.068 to -0.026; PIVW = 1.5E-5). The "glyoxylate and dicarboxylate metabolism" pathway showed significant relevance to CKD development (P = 6E-4), whereas the "glycine, serine, and threonine metabolism" pathway was also recognized as associated with CKD by general practitioners (P = 7E-4). Colocalization analysis revealed a robust genetic link between N-acetylornithine and both CKD and eGFR, with 85.1% and 99.4% colocalization rates, respectively. IVW-MR analysis substantiated these findings with a significant positive association for CKD (odds ratio = 1.43, P = 4.7E-5) and a negative correlation with eGFR (b = -0.04, P = 1.13E-31). Conclusions: MR was utilized to explore the potential causal links between 61 genetic serum metabolites and CKD. N-acetylornithine and NAT8 were further explored as a potential therapeutic target for CKD treatment.

Remnant cholesterol is an independent risk factor for the incidence of chronic kidney disease in newly-diagnosed type 2 diabetes: A nationwide population-based study

AIMS

To evaluate the impact of remnant cholesterol (remnant-C) on chronic kidney disease (CKD) incidence in newly-diagnosed type 2 diabetes.

METHODS

This retrospective cohort study used Korean National Health Insurance Service data on 212,836 patients with newly-diagnosed type 2 diabetes between 2009 and 2014. We conducted cox regression analysis to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for developing CKD according to remnant-C tertile.

RESULTS

During a median follow-up duration of 5.23 years, 6,850 CKD cases developed. In the fully adjusted model, HRs and 95 % CIs for incident CKD increased in the highest tertile of baseline remnant-C compared to the lowest (HR [95 % CI]; 1.234 [1.159-1.314]). This association was more prominent in patients with hypertension or low-income status (P for interaction < 0.05). Increased HRs in the highest tertile of remnant-C was sustained in type 2 diabetes patients within target range of conventional lipid profile such as low-density lipoprotein cholesterol (LDL-C) < 100 mg/dL and < 70 mg/dL (1.165 [1.041-1.304] and 1.308 [1.063-1.609]), high-density lipoprotein cholesterol (HDL-C) (1.243 [1.155-1.338]) and triglyceride (1.168 [1.076-1.268]), respectively.

CONCLUSIONS

In newly-diagnosed type 2 diabetes patients, higher remnant-C is independently associated with CKD incidence, even when conventional lipid values are well-controlled.

Association of Serum Levels of Cholesterol Absorption and Synthesis Markers with the Presence of Cardiovascular Disease: The CACHE Study CVD Analysis

AIM

Serum levels of cholesterol absorption and synthesis markers have been associated with cardiovascular risk in the United States and European countries. In this study, we examined the relevance of these biomarkers and the presence of cardiovascular disease (CVD) in Japanese individuals.

METHODS

The CACHE consortium, comprising of 13 research groups in Japan possessing data on campesterol, an absorption marker, and lathosterol, a synthesis marker measured by gas chromatography, compiled the clinical data using the REDCap system.

RESULTS

Among the 2,944 individuals in the CACHE population, those with missing campesterol or lathosterol data were excluded. This cross-sectional study was able to analyze data from 2,895 individuals, including 339 coronary artery disease (CAD) patients, 108 cerebrovascular disease (CeVD) patients, and 88 peripheral artery disease (PAD) patients. The median age was 57 years, 43% were female, and the median low-density lipoprotein cholesterol and triglyceride levels were 118 mg/dL and 98 mg/dL, respectively. We assessed the associations of campesterol, lathosterol, and the ratio of campesterol to lathosterol (Campe/Latho ratio) with the odds of CVD using multivariable-adjusted nonlinear regression models. The prevalence of CVD, especially CAD, showed positive, inverse, and positive associations with campesterol, lathosterol, and the Campe/Latho ratio, respectively. These associations remained significant even after excluding individuals using statins and/or ezetimibe. The associations of the cholesterol biomarkers with PAD were determined weaker than those with CAD. Contrarily, no significant association was noted between cholesterol metabolism biomarkers and CeVD.

CONCLUSION

This study showed that both high cholesterol absorption and low cholesterol synthesis biomarker levels were associated with high odds of CVD, especially CAD.

Association between remnant cholesterol level and severity of chronic kidney disease in patients with type 2 diabetes

BACKGROUND

Studies on whether remnant cholesterol (RC) affects the progression of chronic kidney disease (CKD) remain insufficient. This study aimed to determine whether RC level was associated with the severity of CKD in patients with type 2 diabetes mellitus (T2DM).

METHODS

In total, 3383 individuals diagnosed with T2DM were enrolled in this cross-sectional study from China. The severity of CKD was defined as no, moderate, severe, and very severe CKD based on the urinary albumin-to-creatinine ratio and estimated glomerular filtration rate. Because RC was non-normally distributed, it was log-transformed and categorized into quantiles. Multivariate logistic regression and multivariate ordinal logistic regression analysis were performed to investigate whether RC was independently associated with CKD and its severity.

RESULTS

The median RC level was 25.9 mg/dL. The number of patients with no, moderate, severe, and very severe CKD was 2587 (76.5 %), 520 (15.4 %), 189 (5.6 %), and 87 (2.5 %), respectively. After adjusting for confounding factors, the prevalence of CKD increased 1.67-fold when the log-transformed RC level was elevated by one unit (OR [95 % CI], 1.67 [1.43-1.95]). The likelihood of CKD severity increasing by one degree was 1.76-fold for each one-unit increase in log-transformed RC level (OR [95 % CI], 1.76 [1.52-2.05]). When RC was incorporated as a categorical variable, it still correlated with CKD severity compared with quantile 1 (Q1) (Q2, 1.30 [1.01-1.68]; Q3, 1.60 [1.23-2.07]; Q4, 2.39 [1.86-3.09]). The association remained regardless of whether the patient's traditional lipid profiles achieved the target range.

CONCLUSION

RC level was associated with CKD severity even when traditional lipid profiles were within the target range in patients with T2DM.

Association between remnant cholesterol and chronic kidney disease in Chinese hypertensive patients

Background

Remnant cholesterol (RC) and chronic kidney disease (CKD) have not been definitively linked in individuals with different characteristics. This study aims to investigate the relationship between serum RC level and CKD and examine possible effect modifiers in Chinese patients with hypertension.

Methods

Our study is based on the Chinese H-type Hypertension Project, which is an observational registry study conducted in real-world settings. The outcome was CKD, defined as an estimated glomerular filtration rate of less than 60 ml/min·1.73 m2. Multivariate logistic regression and smooth curve fitting were used to analyze the association between RC and CKD. Subgroup analyses were subsequently conducted to examine the effects of other variables.

Results

The mean age of the 13,024 patients with hypertension at baseline was 63.8 ± 9.4 years, and 46.8% were male. A conspicuous linear positive association was observed between RC level and CKD (per SD increment; odds ratio [OR], 1.15; 95% confidence interval [CI], 1.08-1.23). Compared with the lowest quartile group of RC, the risk of CKD was 53% higher (OR, 1.53; 95% CI, 1.26-1.86) in the highest quartile group. Furthermore, a stronger positive association between RC level and CKD was found among participants with a higher body mass index (BMI <24 vs. ≥24 kg/m2; P-interaction = 0.034) or current non-smokers (smoker vs. non-smoker; P-interaction = 0.024).

Conclusions

Among Chinese adults with hypertension, RC level was positively associated with CKD, particularly in those with a BMI of ≥24 kg/m2 and current non-smokers. These findings may help improve lipid management regimens in patients with hypertension.

Significance of Circulating Remnant Lipoprotein Cholesterol Levels Measured by Homogeneous Assay in Patients with Type 2 Diabetes

Remnant lipoproteins (RLs), which are typically present at high concentrations in patients with type 2 diabetes mellitus (T2DM), are associated with cardiovascular disease (CVD). Although an RL cholesterol homogeneous assay (RemL-C) is available for the measurement of RL concentrations, there have been no studies of the relationship between RemL-C and clinical parameters in T2DM. Therefore, we evaluated the relationships between RemL-C and CVD-related parameters in patients with T2DM. We performed a cross-sectional study of 169 patients with T2DM who were hospitalized at Kumamoto University Hospital. Compared with those with low RemL-C, those with higher RemL-C had higher fasting plasma glucose, homeostasis model assessment for insulin resistance (HOMA-R), total cholesterol, triglyceride, small dense low-density lipoprotein cholesterol (sdLDL-C), and urinary albumin-creatinine ratio; and lower high-density lipoprotein cholesterol, adiponectin, and ankle brachial pressure index (ABI). Multivariate logistic regression analysis showed that sdLDL-C and ABI were significantly and independently associated with high RemL-C. Although LDL-C was lower in participants with CVD, there was no difference in RemL-C between participants with or without CVD. Thus, RemL-C may represent a useful index of lipid and glucose metabolism, and that may be a marker of peripheral atherosclerotic disease (PAD) in male patients with T2DM.

Association of Kidney Function with Serum Levels of Cholesterol Absorption and Synthesis Markers: The CACHE Study CKD Analysis

AIM

Serum levels of cholesterol absorption and synthesis markers are known to be associated with cardiovascular risk. Individuals with reduced kidney function or chronic kidney disease (CKD) are at an increased risk for cardiovascular disease. Hence, we examined the relationship between estimated glomerular filtration rate (eGFR) and serum markers of cholesterol absorption and synthesis.

METHODS

The CACHE (Cholesterol Absorption and Cholesterol synthesis in High-risk patiEnts) Consortium, comprised of 13 research groups in Japan possessing data of lathosterol (Latho, synthesis marker) and campesterol (Campe, absorption marker) measured via gas chromatography, compiled the clinical data using the REDCap system. Among the 3597 records, data from 2944 individuals were utilized for five analyses including this CKD analysis.

RESULTS

This study analyzed data from 2200 individuals including 522 hemodialysis patients; 42.3% were female, the median age was 58 years, and the median eGFR was 68.9 mL/min/1.73 m2. Latho, Campe, and Campe/Latho ratio were significantly different when compared across CKD stages. When the associations of eGFR with these markers were assessed with multivariable nonlinear regression models, Latho, Campe, and Campe/Latho ratio showed positive, inverse, and inverse associations with eGFR. These associations were significantly modified by sex, the presence/absence of diabetes mellitus, and the presence/absence of statin use.

CONCLUSION

We showed that individuals with lower eGFR have lower cholesterol synthesis marker levels and higher cholesterol absorption marker levels in this large sample.

Association of baseline and cumulative remnant cholesterol with incidence of diabetic nephropathy: A longitudinal cohort study

AIMS

To evaluate the longitudinal association of remnant cholesterol with the incidence of diabetic nephropathy using a Chinese diabetes cohort.

METHODS

We included 4237 individuals with type 2 diabetes during 2013-2014 from Beijing Health Management Cohort. Remnant cholesterol was defined by Martin-Hopkins equation. Diabetic nephropathy was confirmed by urine albumin/creatinine ratio and estimated glomerular filtration rate. We calculated the hazard ratio (HR) and 95% confidence interval (CI) for incident diabetic nephropathy using adjusted Cox proportional hazards regression.

RESULTS

The median [IQR] age was 55 [48, 64] years, and 3 256 (76.8 %) were men. During follow-up, 248 (5.9 %) participants developed diabetic nephropathy. One-SD increase of baseline and average cumulative remnant cholesterol were significantly associated with an increased risk of diabetic nephropathy, and the adjusted HRs were 1.208 (95 % CI: 1.098-1.329) and 1.216 (95 % CI: 1.102-1.341), respectively. Individuals in the highest tertile of baseline and average cumulative remnant cholesterol had a 82.3 % and 87.6 % excess risk of diabetic nephropathy, compared with those in the lowest.

CONCLUSION

Remnant cholesterol is independently associated with incident diabetic nephropathy in type 2 diabetes.

Serum phosphate as an independent factor associated with cholesterol metabolism in patients undergoing hemodialysis: a cross-sectional analysis of the DREAM cohort

Background

Hyperphosphatemia is a risk factor for cardiovascular outcomes in patients with chronic kidney disease. In an experimental model, hyperphosphatemia promotes atherosclerosis by activating sterol regulatory element-binding protein 2 which controls cholesterol homeostasis. In the present study, we hypothesized that serum phosphate level is associated with cholesterol metabolism in patients with kidney failure.

Methods

We conducted a single center cross-sectional study including 492 patients undergoing hemodialysis and 100 healthy controls not on statin or ezetimibe treatment. Serum lathosterol and campesterol levels were measured as a marker of cholesterol synthesis and absorption, respectively. As compared to the control group, the hemodialysis patients had higher median (interquartile range) phosphate [5.8 (5.0 to 6.6) vs. 3.3 (3.0 to 3.6) mg/dL, P &lt; 0.001], lower lathosterol [1.2 (0.8 to 1.7) vs. 2.6 (1.9 to 3.4) µg/mL, P &lt; 0.001] and higher campesterol levels [4.5 (3.6 to 6.0) vs. 4.1 (3.2 to 5.4) µg/mL, P = 0.02]. Serum phosphate correlated positively to campesterol in the control group (Spearman's r = 0.21, P = 0.03) and in the hemodialysis patients (Spearman's r = 0.19, P &lt; 0.001). The positive association between phosphate and campesterol levels in the hemodialysis group remained significant in multivariable-adjusted linear regression analysis. There was no significant association between phosphate and lathosterol in either group.

Conclusions

An independent association was found between phosphate and campesterol levels in patients with kidney failure. This study suggests a novel relationship between phosphate and cholesterol metabolism, both of which could affect cardiovascular outcomes in this population.

Remnant cholesterol predicts progression of diabetic nephropathy and retinopathy in type 1 diabetes

BACKGROUND

We aimed to assess whether remnant cholesterol concentration and variability predict the progression of diabetic nephropathy (DN) and severe diabetic retinopathy (SDR) in type 1 diabetes.

METHODS

This observational prospective study covered 5150 FinnDiane Study participants. Remnant cholesterol was calculated as total cholesterol - LDL cholesterol - HDL cholesterol and variability as the coefficient of variation. DN category was based on consensus albuminuria reference limits and the progression status was confirmed from medical files. SDR was defined as retinal laser treatment. For 1338 individuals, the severity of diabetic retinopathy (DR) was graded using the ETDRS classification protocol. Median (IQR) follow-up time was 8.0 (4.9-13.7) years for DN and 14.3 (10.4-16.3) for SDR.

RESULTS

Remnant cholesterol (mmol L^-1 ) was higher with increasing baseline DN category (P < 0.001). A difference was also seen comparing non-progressors (0.41 [0.32-0.55]) with progressors (0.55 [0.40-0.85]), P < 0.001. In a Cox regression analysis, remnant cholesterol predicted DN progression, independently of diabetes duration, sex, HbA_1c , systolic blood pressure, smoking, BMI, estimated glucose disposal rate and estimated glomerular filtration rate (HR: 1.51 [1.27-1.79]). Remnant cholesterol was also higher in those who developed SDR (0.47 [0.36-0.66]) than those who did not (0.40 [0.32-0.53]), P < 0.001, and the concentration increased stepwise with increasing DR severity (P < 0.001). Regarding SDR, the HR for remnant cholesterol was 1.52 (1.26-1.83) with the most stringent adjustment. However, remnant cholesterol variability was not independently associated with the outcomes.

CONCLUSIONS

Remnant cholesterol concentration, but not variability, predicts DN progression and development of SDR. However, it remains to be elucidated whether the associations are causal or not.

Markers of cholesterol synthesis to cholesterol absorption across the spectrum of non-dialysis CKD: An observational study

In dialysis patients, cholesterol-lowering therapy with statins is less effective than in other high-risk patients. This may be explained by a shift from cholesterol synthesis toward cholesterol absorption. In line, markers of cholesterol absorption-such as campesterol-better predict atherosclerotic cardiovascular events than markers of cholesterol synthesis-such as lathosterol-in dialysis patients. To test the association between markers of cholesterol absorption such as campesterol-and markers of cholesterol synthesis-such as lathosterol-against cardiovascular events in non-dialysis CKD patients. Altogether 251 patients those not on lipid-lowering agents were followed annually for the composite endpoint atherosclerotic cardiovascular disease (ASCVD) and all-cause death. During follow-up of 5.2 ± 2.1 years, 61 participants reached the primary endpoint atherosclerotic cardiovascular disease/all-cause death [ASCVD/D], 47 participants suffered from ASCVD, and 46 participants died. In univariate Cox regression analysis, campesterol/lathosterol ratio did not significantly predict ASCVD/D (HR 0.643; 0.358-1.155; 3rd vs. 1st tertile), all-cause death (HR 1.309; 0.604-2.838; 3rd vs. 1st tertile) nor ASCVD (HR 0.589; 0.311-1.118; 3rd vs. 1st tertile). We did not observe a shift from cholesterol synthesis to cholesterol absorption across the spectrum of non-dialysis CKD. Campesterol/lathosterol ratio did not predict future ASCVD or all-cause death in non-dialysis CKD.

A study on the correlation between remnant cholesterol and urinary albumin to creatinine ratio in Chinese community adults: A report from the REACTION study

BACKGROUND

The correlation between remnant cholesterol (RC) and urinary albumin to creatinine ratio (UACR) has not been illustrated. The present study aims to explore the correlation between RC levels and UACR in Chinese community adults.

METHODS

This study included 35 848 participants from a cohort study (REACTION). The UACR data were divided into three groups: UACR <10 mg/g, 10 ≤UACR<30 mg/g, and UACR ≥30 mg/g groups. RC was divided into two groups, according to the 75th percentile: <75% group and ≥75% group. Multiple logistic regression analysis was used to evaluate the correlation between RC and UACR.

RESULTS

The RC exhibited an adjusted odds ratio that was significant in models 1-5. Although all confounders were corrected in model 5, RC and UACR were still significantly correlated， and the correlation was more significant in females，when compared to males (odds ratio [OR]: 1.117, 95% CI: 1.063-1.176, P < 0.001 for all subjects; OR: 1.092, 95% CI: 1.128-1.161, P = 0.004 for females; and OR: 1.085, 95% CI: 0.998-1.194, P = 0.088 for males). The RC was significantly correlated with UACR for subjects with 5.6 ≤ fasting blood glucose < 7.0 or 7.8 ≤ post-load blood glucose < 11.1 mmol/L, 24 ≤ body mass index (BMI) < 28 kg/m² , 120 ≤ systolic blood pressure < 140 and/or 80 ≤ diastolic blood pressure < 90 mm Hg.

CONCLUSIONS

In the Chinese community, RC is highly correlated with UACR, and the correlation is more significant in females compared with males. At higher RC levels, patients with critical values of blood pressure, BMI and blood glucose have a more significant correlation between RC and UACR.

Impact of statin-ezetimibe combination on coronary atheroma plaque in patients with and without chronic kidney disease - Sub-analysis of PRECISE-IVUS trial

BACKGROUND

Chronic kidney disease (CKD) deteriorates the prognosis of patients undergoing percutaneous coronary intervention (PCI). Because coronary artery disease (CAD) is the major cause of death in CKD patients, cardiovascular risk reduction has been clinically important in CKD. We hypothesized intensive lipid-lowering with statin/ezetimibe attenuated coronary atherosclerotic development even in patients with CKD.

METHODS

In the prospective, randomized, controlled, multicenter PRECISE-IVUS trial, 246 patients undergoing intravascular ultrasound (IVUS)-guided PCI were randomly assigned to receive atorvastatin/ezetimibe combination or atorvastatin alone (the dosage of atorvastatin was up-titrated to achieve the level of low-density lipoprotein cholesterol < 70 mg/dL). Serial volumetric IVUS findings obtained at baseline and 9-12 month follow-up to quantify the coronary plaque response in 202 patients were compared stratified by the presence or absence of CKD.

RESULTS

CKD was observed in 52 patients (26%) among 202 enrolled patients. Compared with the non-CKD group, the CKD group was significantly older (71.5 ± 8.6 years vs. 64.4 ± 9.6 years, P < 0.001) with similar prevalence of comorbid coronary risk factors and lipid profiles. Similar to the non-CKD group (-1.4 [-2.8 to -0.1]% vs. -0.2 [-1.7 to 1.0]%, P = 0.002), the atorvastatin/ezetimibe combination significantly reduced ∆PAV compared with atorvastatin alone even in the CKD group (-2.6 [-5.6 to -0.4]% vs. -0.9 [-2.4 to 0.2]%, P = 0.04).

CONCLUSIONS

As with non-CKD, intensive lipid-lowering therapy with atorvastatin/ezetimibe demonstrated stronger coronary plaque regression effect even in patients with CKD compared with atorvastatin monotherapy.

TRIAL REGISTRATION

NCT01043380 (ClinicalTrials.gov).

[Chronic kidney disease and dyslipidaemia]

Chronic kidney disease (CKD) has to be considered as a high, or even very high risk cardiovascular risk condition, since it leads to an increase in cardiovascular mortality that continues to increase as the disease progresses. An early diagnosis of CKD is required, together with an adequate identification of the risk factors, in order to slow down its progression to more severe states, prevent complications, and to delay, whenever possible, the need for renal replacement therapy. Dyslipidaemia is a factor of the progression of CKD that increases the risk in developing atherosclerosis and its complications. Its proper control contributes to reducing the elevated cardiovascular morbidity and mortality presented by these patients. In this review, an assessment is made of the lipid-lowering therapeutic measures required to achieve to recommended objectives, by adjusting the treatment to the progression of the disease and to the characteristics of the patient. In CKD, it seems that an early and intensive intervention of the dyslipidaemia is a priority before there is a significant decrease in kidney function. Treatment with statins has been shown to be safe and effective in decreasing LDL-Cholesterol, and in the reduction of cardiovascular events in individuals with CKD, or after renal transplant, although there is less evidence in the case of dialysed patients.

Postprandial Hyperlipidemia and Remnant Lipoproteins

Fasting hypertriglyceridemia is positively associated with the morbidity of coronary heart disease (CHD), and postprandial (non-fasting) hypertriglyceridemia is also correlated with the risk status for CHD, which is related to the increase in chylomicron (CM) remnant lipoproteins produced from the intestine. CM remnant particles, as well as oxidized low density lipoprotein (LDL) or very low density lipoprotein (VLDL) remnants, are highly atherogenic and act by enhancing systemic inflammation, platelet activation, coagulation, thrombus formation, and macrophage foam cell formation. The cholesterol levels of remnant lipoproteins significantly correlate with small, dense LDL; impaired glucose tolerance (IGT) and CHD prevalence. We have developed an assay of apolipoprotein (apo)B-48 levels to evaluate the accumulation of CM remnants. Fasting apoB-48 levels correlate with the morbidity of postprandial hypertriglyceridemia, obesity, type III hyperlipoproteinemia, the metabolic syndrome, hypothyroidism, chronic kidney disease, and IGT. Fasting apoB-48 levels also correlate with carotid intima-media thickening and CHD prevalence, and a high apoB-48 level is a significant predictor of CHD risk, independent of the fasting TG level. Diet interventions, such as dietary fibers, polyphenols, medium-chain fatty acids, diacylglycerol, and long-chain n-3 polyunsaturated fatty acids (PUFA), ameliorate postprandial hypertriglyceridemia, moreover, drugs for dyslipidemia (n-3 PUFA, statins, fibrates or ezetimibe) and diabetes concerning incretins (dipeptidyl-peptidase IV inhibitor or glucagon like peptide-1 analogue) may improve postprandial hypertriglyceridemia. Since the accumulation of CM remnants correlates to impaired lipid and glucose metabolism and atherosclerotic cardiovascular events, further studies are required to investigate the characteristics, physiological activities, and functions of CM remnants for the development of new interventions to reduce atherogenicity.

Enhanced Impact of Cholesterol Absorption Marker on New Atherosclerotic Lesion Progression After Coronary Intervention During Statin Therapy

Aim: Clinical trials suggest that residual risks remain for coronary artery disease (CAD) during low-density lipoprotein cholesterol (LDL-C) lowering therapy. We aimed to investigate the role of exogenous lipids in the prognosis of CAD after percutaneous coronary intervention (PCI).

Methods: A total of 145 patients with CAD, who underwent elective PCI, and 82 non-CAD (control) patients were enrolled in this study. CAD patients underwent follow-up coronary angiography 6–9 months after PCI, and were classified into three groups: 1) patients who showed in-stent restenosis (ISR) in the original stented segment, 2) patients with other non-target coronary atherosclerotic lesions (de novo), and 3) patients with neither ISR nor a de novo lesion. Biochemical analyses were performed on fasting serum samples at the time of follow-up coronary angiography.

Results: Despite the controlled serum LDL-C levels, CAD patients with statin showed elevated cholesterol absorption marker campesterol/total cholesterol (TC), synthesis marker lathosterol/TC, campesterol/lathosterol ratio, and apolipoprotein B48 (apoB48) concentration compared with non-CAD patients. The high campesterol/TC, campesterol/lathosterol ratio, and apoB48 concentration were associated with de novo lesion progression after PCI. In stepwise multivariate logistic regression analysis, campesterol/TC and apoB48 concentrations were independent risk factors for de novo lesion progression in statin-treated CAD patients after PCI.

Conclusion: The increase of cholesterol absorption marker and apoB48 concentration may lead to the progression of de novo lesions, and these markers may represent a residual risk during statin treatment after PCI.

Remnant lipoproteinemia predicts cardiovascular events in patients with type 2 diabetes and chronic kidney disease

BACKGROUND

Patients having type 2 diabetes mellitus (DM) and chronic kidney disease (CKD) are at high risk of cardiovascular events. Triglyceride-rich lipoprotein levels are synergistically increased in patients with DM and CKD. This study examined the predictive value of remnant lipoprotein levels for cardiovascular events in patients with DM and CKD.

METHODS

Three hundred and sixty-five patients with type 2 DM and CKD were enrolled. Serum levels of remnant lipoproteins (remnant-like lipoprotein particles cholesterol; RLP-C) were measured by an immunoseparation method. All patients were followed prospectively for a period of 45±23 months or until occurrence of one of the following events: cardiac death, non-fatal myocardial infarction, unstable angina requiring unplanned coronary revascularization, or ischemic stroke.

RESULTS

During the follow-up period, 59 patients had cardiovascular events. Multivariate Cox analysis revealed that high levels of RLP-C (≥4.3mg/dL; median value) were a significant risk factor for cardiovascular events, independent of traditional risk factors (HR: 1.30; 95% CI: 1.04-1.63; p=0.02). The addition of high levels of RLP-C to traditional risk factors improved net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.36, p=0.01; and IDI 0.03, p=0.02).

CONCLUSIONS

RLP-C is useful for risk assessment of future cardiovascular events in patients having type 2 DM and CKD.

Current Focuses in Serum Lipid Abnormalities in Dialysis Patients

BACKGROUND

Dyslipidemia is a common metabolic complication in patients with chronic kidney disease and is detected as changes in lipoprotein concentrations in serum.

SUMMARY

Recently, other features of lipid abnormalities have been described, such as alterations in serum n-3 polyunsaturated fatty acids, cholesterol metabolism (proportion of hepatic synthesis and intestinal absorption), and dysfunctional high-density lipoprotein.

KEY MESSAGES

Since abnormalities of these new aspects predict adverse outcomes in hemodialysis populations, they may be helpful in risk stratification of patients and could also be new targets for prevention.