The effect of triglycerides to high-density lipoprotein cholesterol ratio on the reduction of renal function: findings from China health and retirement longitudinal study (CHARLS)

Comprehensive assessment of the combined impact of dyslipidemia and inflammation on chronic kidney disease development: A prospective cohort study

BACKGROUND

There remains a limited comprehensive understanding of how dyslipidemia and chronic inflammation collectively contribute to the development of chronic kidney disease (CKD).

OBJECTIVE

We aimed to identify clusters of individuals with five variables, including lipid profiles and C-reactive protein (CRP) levels, and to assess whether the clusters were associated with incident CKD risk.

METHODS

We used the Korean Genome and Epidemiology Study-Ansan and Ansung data. K-means clustering analysis was performed to identify distinct clusters based on total cholesterol, triglyceride, non-high-density lipoprotein (HDL)-C, HDL-C, and CRP levels. Cox proportional hazards models were used to examine the association between incident CKD risk and the different clusters.

RESULTS

During the mean 10-year follow-up period, CKD developed in 1,645 participants (690 men and 955 women) among a total of 8,053 participants with a mean age of 51.8 years. Four distinct clusters were identified: C1, low cholesterol group (LC); C2, high-density lipoprotein cholesterol group (HC); C3, insulin resistance and inflammation group (IIC); and C4, dyslipidemia and inflammation group (DIC). Cluster 4 had a significantly higher risk of incident CKD compared to clusters 2 (hazard ratio (HR) 1.455 [95% confidence interval (CI) 1.234-1.715]; p < 0.001) and cluster 1 (HR 1.264 [95% CI 1.067-1.498]; p = 0.007) after adjusting for confounders. Cluster 3 had a significantly higher risk of incident CKD compared to clusters 2 and 1.

CONCLUSION

Clusters 4 and 3 had higher risk of incident CKD compared to clusters 2 and 1. The combination of dyslipidemia with inflammation or insulin resistance with inflammation appears to be pivotal in the development of incident CKD.

Establishment and evaluation of a nomogram prediction model for the risk of vascular calcification in stage 5 chronic kidney disease patients

Vascular calcification (VC) is a common complication of chronic kidney disease (CKD) that has a detrimental effect on patients' survival and prognosis. The aim of this study was to develop and validate a practical and reliable prediction model for VC in CKD5 patients. The medical records of 544 CKD5 patients were reviewed retrospectively. Multivariate logistic regression analysis was used to identify the independent risk factors for vascular calcification in patients with CKD5 and then created a nomogram prediction model. The area under the receiver operating characteristic curve (AUC), Hosmer-Lemeshow test, and decision curve analysis (DCA) were used to assess model performance. The patients were split into groups with normal and high serum uric acid levels, and the factors influencing these levels were investigated. Age, BUN, SUA, P and TG were independent risk factors for vascular calcification in CKD5 patients in the modeling group (P < 0.05). In the internal validation, the results of model showed that the AUC was 0.917. No significant divergence between the predicted probability of the nomogram and the actual incidence rate (x2 = 5.406, P = 0.753) was revealed by the calibration plot and HL test, thus confirming that the calibration was satisfactory. The external validation also showed good discrimination (AUC = 0.973). The calibration chart and HL test also demonstrated good consistency. Besides, the correlation analysis of serum uric acid levels in all CKD5 patients revealed that elevated uric acid levels may be related to gender, BUN, P, and TG.

Relationship of serum lipid parameters with kidney function decline accompanied by systemic arterial stiffness: a retrospective cohort study

Background

Dyslipidemia is associated with kidney function decline (KFD), although the non-linear relationship of lipid parameters to KFD has not been fully elucidated. We aimed to determine the detailed relationship of baseline lipid parameters with KFD, considering the mediation of arterial stiffness.

Methods

A total of 27 864 urban residents with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 at baseline, who participated in a median of three (range two to eight) consecutive annual health examinations were studied. Arterial stiffness was assessed by cardio-ankle vascular index (CAVI). KFD was defined as development of eGFR <60 mL/min/1.73 m2.

Results

During the study period, 1837 participants (6.6%) developed KFD. Receiver operating characteristic analysis determined that the cutoff values independently associated with KFD are 123 mg/dL for low-density lipoprotein cholesterol (LDL-C) [area under the curve (95% confidence interval) 0.570 (0.557-0.583)], 65 mg/dL for high-density lipoprotein cholesterol (HDL-C) [0.552 (0.539-0.566)], 82 mg/dL for triglycerides (TG) [0.606 (0.593-0.618)] and 1.28 for TG/HDL-C ratio [0.600 (0.587-0.612)]. These cut-offs were independently associated with KFD in Cox analysis. Regarding the contribution of each lipid parameter to KFD, a linear relationship was observed for both TG and TG/HDL-C, and a U-shaped relationship for HDL-C. A adjusted mediating effect of CAVI on the relationship of TG or TG/HDL-C ratio with KFD was observed (mediating rate: 2.9% in TG, 2.5% in TG/HDL-C ratio). Regarding the association to KFD, a linear relationship was observed for both TG and TG/HDL-C, and a U-shaped relationship for HDL-C. A mediating effect of CAVI on the relationship of TG or TG/HDL-C ratio with KFD was observed after adjustment for confounders.

Conclusions

TG and TG/HDL-C ratio related linearly to KFD and this was partially mediated by CAVI. A U-shaped relationship was observed between HDL-C and KFD risk. LDL-C showed no significant association. Further study should investigate whether intensive TG-lowering treatment prevents KFD via decreasing CAVI.

Correlation between the increase in serum uric acid and the rapid decline in kidney function in adults with normal kidney function: a retrospective study in Urumqi, China

BACKGROUND

To examine the association between elevated serum uric acid (SUA) levels and the rapid decline in kidney function by conducting a retrospective cohort study on a physically healthy population in Urumqi, China.

METHODS

A cohort study of 2,802 physically healthy people with a normal estimated glomerular filtration rate (eGFR) was investigated from 2018 to 2021. The examination procedure included using questionnaires, taking physical measurements, and blood sampling. The rapid decline in kidney function was defined as eGFR > 5 mL·min^-1 ·(1.73 m² )^-1 year. The relationship between elevated SUA levels and the rapid decline in kidney function was assessed.

RESULTS

When performing the three-year retrospective analysis, 688 (28.55%) cases experienced a rapid decline in kidney function, and 52 (1.9%) cases developed chronic kidney disease (CKD). They were divided into the stable group and the rapidly declining kidney function group according to eGFR > 15 mL·min^-1·(1.73 m² )^-1. The comparison revealed a greater increase in uric acid in the rapidly declining kidney function group [0.30 (-0.29, 0.82) mg/dL vs. - 0.07(-0.54, 0.37) mg/dL, Z = - 8.822, P < 0.001]. The participants were further divided into four groups according to their uric acid levels in 2018 and 2021, which included the normal to normal (N-N) group, the normal to hyperuricemia (HUA) (N-H) group, the HUA to normal (H-N) group, and the persistently HUA (H-H) group. The decrease in eGFR was significantly higher in the N-H group than in the other three groups (χ² = 20.580, P < 0.001). The results of the multifactorial logistic regression analysis showed that elevated uric acid was a risk factor for the rapid decline in kidney function (OR = 1.640, P < 0.001).

CONCLUSION

Elevated SUA levels were a risk factor for the rapid decline in kidney function in the Chinese health examination population. Higher SUA levels might predict the occurrence of progressive kidney impairment.

Co-exposure to perfluoroalkyl acids and heavy metals mixtures associated with impaired kidney function in adults: A community-based population study in China

BACKGROUND

Previous studies have separately linked either perfluoroalkyl acid (PFAA) or heavy metal exposure with kidney dysfunction. However, the relationships of co-exposure to PFAAs and heavy metals with kidney function are still unclear.

OBJECTIVES

To explore the associations between exposure to PFAAs and heavy metals mixtures and kidney function in adults.

METHODS

We conducted a cross-sectional community-based population study in Guangzhou, China, enrolling 1312 adults from November 2018 to August 2019. We quantified 13 PFAAs in serum and 14 heavy metals in plasma. We chose estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD) as outcomes of interest. Distributed lag non-linear models (DLNMs) were used to check nonlinearity of individual pollutant with kidney function. Joint associations of pollutant mixtures on kidney function were assessed by Bayesian Kernel Machine Regression (BKMR) models. We further explored modification effects of gender.

RESULTS

Most individual PFAA and heavy metal were associated with declined kidney function in single-pollutant models. We also observed significant dose-response relationships of pollutant mixtures with reduced eGFR levels and increased odds of CKD in BKMR models. Perfluoroheptanesulfonic acid (PFHpS), arsenic (As) and strontium (Sr) were the predominant contributors among pollutant mixtures. A change in log PFHpS, As and Sr concentrations from the 25th to the 75th percentile were associated with a decrease in eGFR of -5.42 (95% confidence interval (CI): -6.86, -3.98), -2.14 (95% CI: -3.70, -0.58) and -1.87 (95% CI: -3.03, -0.72) mL/min/1.73 m², respectively, when other pollutants were at their median values. In addition, the observed associations were more obvious in females.

CONCLUSIONS

We provided new evidence that co-exposure to PFAAs and heavy metals mixtures was associated with reduced kidney function in adults and PFHpS, As and Sr appeared to be the major contributors. Further studies are warranted to confirm our findings and elucidate the underlying mechanisms.

Prognostic Value of Triglyceride to High-Density Lipoprotein Cholesterol Ratio (TG/HDL-C) in IgA Nephropathy Patients

Background

The triglycerides to high-density lipoprotein cholesterol (TG/HDL-C) ratio is an easy-to-use atherogenic and prognostic marker which has attracted increasing attention these days. However, whether TG/HDL-C correlate with outcomes in IgA nephropathy (IgAN) patients remains unknown. To clarify these issues, we conducted this study.

Methods

A total of 1146 patients from West China Hospital of Sichuan University were retrospectively analysed between 2008 and 2018.The demographic, clinical and pathological data of all patients at the time of biopsy were collected. Then, patients were divided into the high TG/HDL group (TG/HDL ≥ 1.495, N=382) and the low TG/HDL group (TG/HDL-C < 1.495, N=764) based on the optimal cut-off value of the TG/HDL-C using receive operating curve. Cox proportional hazard models and Kaplan-Meier curves were used to evaluate the renal outcomes of IgAN.

Results

The median age of the patients was 33 (26-42) years, and 44.5% were men. By correlation analysis, we found that the TG/HDL-C ratio was negatively correlated with the eGFR (r = 0.250, P < 0.001) but positively correlated with proteinuria (r = 0.230, P< 0.001), BMI (r=0.380, P<0.001) and serum uric (r =0.308, P< 0.001). Patients with a higher TG/HDL-C ratio tended to have hypertension [odds ratio (OR), 1.987; 95% CI, 1.527-2.587; P<0.001] and more severe pathologic lesions with tubular atrophy/interstitial fibrosis (OR, 1.610; 95% CI, 1.203-2.154; P=0.001). During a median follow-up period of 54.1 (35.6-73.2) months, a high TG/HDL ratio was strongly associated with worse renal survival in IgAN patients (log-rank: P <0.001). Multivariate Cox analysis demonstrated that a high TG/HDL-C ratio (HR 1.775, 95% CI 1.056-2.798; P=0.029) was an independent predictive marker to ESRD.

Conclusion

In this study, we addressed the importance of TG/HDL-C ratio as a predictive marker for IgAN progression.

Association Between the Surrogate Markers of Insulin Resistance and Chronic Kidney Disease in Chinese Hypertensive Patients

Background

We aim to evaluate the four surrogate markers of insulin resistance (IR), including triglyceride-glucose index (TyG), lipid accumulation product index (LAP), visceral adiposity index (VAI), triglycerides to high-density lipoprotein cholesterol ratio (TG/HDL), on prevalence of chronic kidney disease (CKD) and to examine any possible effect modifiers in Chinese hypertensive patients.

Methods

A total of 13,055 hypertensive participants were included in this cross-sectional study. In addition, average age of the study population was 63.81 ± 9.46 years, and 47.66% of them are men. The primary outcome was CKD, defined as eGFR &lt;60 ml/min/1.73 m2. Multivariate logistic regression analysis and the generalized additive model and a fitted smoothing curve (penalized spline method) were used to examine the association between the surrogate markers of IR and CKD.

Results

Four surrogate markers of IR were independently and positively associated with CKD in a dose-response fashion. The association between four surrogate markers of IR and the prevalence of CKD was examined as a continuous variable per one unit increment and also as a categorical variable using tertiles with the tertiles (T1) as the reference group. In the fully adjusted model, multivariate logistic analyses showed that the per one unit increments of the TyG, LAP, VAI, and TG/HDL ratios were all significantly associated with 42, 31, 67, and 78% higher risk for CKD, respectively. Consistently, the adjusted ORs (95% CI) for CKD were 1.48 (1.21, 1.81), 1.34 (1.06, 1.69), 1.26 (1.03, 1.53), 1.35 (1.12, 1.63) when comparing the highest tertile to the lowest tertile of the TyG, LAP, VAI, and TG/HDL ratios, respectively. The stratification analysis showed that a significant positive correlation between TyG, VAI, and TG/HDL and CKD in patients over 65 years old.

Conclusion

Four surrogate markers of IR were independently and positively correlated with CKD, and LAP was better than the other surrogate markers of IR for predicting CKD. Only among participants aged over 65 years were higher levels of TyG, VAI and TG/HDL found to be closely related to the increased prevalence of CKD.