Serum Albumin and High-Sensitivity C-reactive Protein are Independent Risk Factors of Chronic Kidney Disease in Middle-Aged Japanese Individuals: the Circulatory Risk in Communities Study

Total protein intake and subsequent risk of chronic kidney disease: the Circulatory Risk in Communities Study

BACKGROUND

Whether dietary protein intake worsens renal function in the general population has been discussed but not yet determined. We aimed to examine the longitudinal association between dietary protein intake and risk of incident chronic kidney disease (CKD).

METHODS

We conducted a 12-year follow-up study with 3,277 Japanese adults (1,150 men and 2,127 women) aged 40-74 years, initially free from CKD, who participated in cardiovascular risk surveys from two Japanese communities under the Circulatory Risk in Communities Study. The development of CKD was defined by the estimated glomerular filtration rate (eGFR) during the follow-up period. Protein intake was measured at baseline by using the brief-type self-administered diet history questionnaire. We estimated sex-, age-, community- and multivariate-adjusted hazard ratios (HR) for incident CKD were calculated using the Cox proportional hazards regression models according to quartiles of percentage of energy (%energy) from protein intake.

RESULTS

During 26,422 person-years of follow-up, 300 participants developed CKD (137 men and 163 women). The sex-, age-, and community-adjusted HR (95% confidence interval, CI) for the highest (≥16.9%energy) versus lowest (≤13.4%energy) quartiles of total protein intake was 0.66 (0.48-0.90), p for trend = 0.007. The multivariable HR (95%CI) was 0.72 (0.52-0.99), p for trend = 0.016 after further adjustment for body mass index, smoking status, alcohol drinking status, diastolic blood pressure, antihypertensive medication use, diabetes mellitus, serum total cholesterol levels, cholesterol-lowering medication use, total energy intake, and baseline eGFR. The association did not vary by sex, age, and baseline eGFR. When examining animal and vegetable protein intake separately, the respective multivariable HRs (95%CIs) were 0.77 (0.56-1.08), p for trend = 0.036, and 1.24 (0.89-1.75), p for trend = 0.270.

CONCLUSIONS

Higher protein intake, more specifically animal protein intake was associated with a lower risk of CKD.

Increased LDL cholesterol level is associated with deterioration of renal function in males

Background

Relationships between levels of serum lipid fractions and the time course of renal function are discrepant in the literature. Here we examined this issue by analyses of healthy subjects in a cohort.

Methods

Of all subjects who received health examinations at Keijinkai Maruyama Clinic, Sapporo in 2006, subjects with hypertension, diabetes mellitus or chronic kidney disease (CKD) and those taking medication for dyslipidemia were excluded, and a total of 5,586 subjects (male/female: 3,563/2,023, mean age: 43 ± 8 years) were followed for 10 years.

Results

Linear mixed effect models showed that baseline low-density lipoprotein (LDL)-cholesterol level was negatively associated with estimated glomerular filtration rate (eGFR) during the 10-year follow-up period after adjustment of confounders. Interactions between the follow-up year and baseline level of LDL-cholesterol or high-density lipoprotein (HDL)-cholesterol for eGFR values during the follow-up period were significant in males but not in females. There were no significant interactions for eGFR between the follow-up year and baseline levels of total cholesterol, triglycerides, or HDL-cholesterol/triglycerides ratio. During the follow-up period, 346 males and 223 females developed CKD. When male subjects were divided into subgroups according to tertiles of baseline levels of LDL-cholesterol, the adjusted risk for CKD in the third tertial group was significantly higher than that in the first tertile group as a reference (hazard ratio [95% confidence interval]: 1.39 [1.02-1.90], p = 0.035). Such a difference was not observed for LDL-cholesterol tertiles in females or HDL-cholesterol tertiles in both sexes.

Conclusions

A high LDL-cholesterol level may be a risk factor of new-onset CKD in apparently healthy males.

Association of the serum albumin level with prognosis in chronic kidney disease patients

PURPOSE

Chronic kidney disease (CKD) is an important contributor to the overall morbidity and mortality due to noncommunicable diseases. We investigated the relationship between serum albumin and the clinical prognosis in patients with stage G2-G5 CKD who were not undergoing dialysis.

METHODS

This was a post hoc analysis of 1138 patients enrolled from 2010 to 2011 in the Chronic Kidney Disease Research of Outcomes in Treatment and Epidemiology (CKD-ROUTE) study. The primary endpoints were CKD progression, cardiovascular disease (CVD) development, and all-cause mortality. Cox proportional hazards models were used.

RESULTS

During a median follow-up time of 35 months, the number of patients who experienced CKD progression, CVD development, and all-cause mortality was 278 (24.7%), 116 (10.3%), and 78 (6.9%), respectively. In multivariable-adjusted Cox proportional hazards models, the adjusted hazard ratios (HRs) for CKD progression, CVD development, and all-cause mortality in patients with the highest quartile of serum albumin concentrations compared to those with the lowest quartile of serum albumin concentrations were 0.13 (P < 0.0001), 0.29 (P = 0.0002), and 0.27 (P = 0.0009), respectively, in the model adjusted for demographic factors, hypertension, diabetes, and a history of CVD. After further adjustment for the estimated glomerular filtration rate (eGFR), urinary protein/creatinine ratio (UPCR), and systolic blood pressure (SBP), the results remained significant (HR for CKD progression 0.37, P < 0.0001; HR for CVD development 0.41, P = 0.0120; HR for all-cause mortality 0.37, P = 0.0158).

CONCLUSION

Serum albumin levels were inversely associated with the risks of CKD progression, CVD development, and all-cause mortality among patients with stage G2-G5 CKD who were not undergoing dialysis.

Combined impact of residual inflammatory risk and chronic kidney disease on long-term clinical outcomes in patients undergoing percutaneous coronary intervention

BACKGROUND

Inflammatory status is associated with cardiovascular events in patients with coronary artery disease (CAD) and renal function impairment. Chronic kidney disease (CKD) increases the incidence of cardiovascular events. However, whether the presence of residual inflammatory risk (RIR) and CKD together has a synergistic effect on the long-term clinical outcomes of patients with stable CAD undergoing percutaneous coronary intervention (PCI) remains unclear.

METHODS

We assessed 2,948 consecutive patients with stable CAD who underwent the first PCI from 2000 to 2016. Of these, we analyzed the data of patients (2,087) with measurements of high-sensitivity C-reactive protein (hs-CRP) available at follow-up (6-9 months later). High RIR was defined as hs-CRP of >0.6 mg/L according to the median value at follow-up. Patients were classified into four groups: Group 1 (low RIR, non-CKD), Group 2 (high RIR, non-CKD), Group 3 (low RIR, CKD), and Group 4 (high RIR, CKD). We evaluated all-cause mortality and major adverse cardiac events (MACE). The median follow-up period was 5.2 (interquartile range, 1.9-9.9) years.

RESULTS

In total, 189 (16.1%) and 128 (11.2%) cases of all-cause mortality and MACE, respectively, were identified during follow-up. The rates of all-cause mortality and MACE were significantly higher in Group 4 than those in the other groups (p<0.001). There was a stepwise increase in the incidence of all-cause mortality and MACE. Upon adjustment for important covariates, the presence of high RIR and/or CKD showed an independent association with a high incidence of MACE and all-cause mortality.

CONCLUSIONS

The presence of high RIR and CKD conferred a synergistic adverse effect on the long-term clinical outcomes of patients undergoing PCI.

Evaluation of cardiovascular events and progression to end-stage renal disease in patients with dyslipidemia and chronic kidney disease from the North-Eastern area of Romania

PURPOSE

The aim of this prospective cohort study was: to identify the association between different biomarkers [proprotein convertase subtilisin/kexin 9-PCSK9, lipoprotein(a)-Lp(a) and high-sensitivity C-reactive protein-hsCRP] and the cardiovascular events; to evaluate the relationship between the 3 biomarkers mentioned above and the renal outcomes that contributed to end-stage renal disease (ESRD).

METHODS

We studied 110 patients with chronic kidney disease (CKD) stages 2 to 4. The identification of the new cardiovascular events and the renal outcomes were performed by clinical and paraclinical explorations.

RESULTS

350 patients were examined and 110 (31.4%) were included in this study. The mean age was 55.6 ± 10.9 years, with a higher number of men compared to women. The CKD patients with de novo cardiovascular events and new renal outcome during the study, had significantly increased values of total cholesterol (TC), low density cholesterol lipoprotein (LDL-C) at 6 and 12 months and higher levels of Lp(a), PCSK9, hsCRP and low ankle-brachial index (ABI) and ejection fraction (EF) values compared to patients without cardiovascular and renal events. In CKD patients, PCSK9 > 220 ng/mL was a predictor of cardiovascular events, while the EF < 50% was a predictor for renal outcomes. For CKD patients with PCSK9 > 220 ng/mL and hsCRP > 3 mg/L levels, the time-interval for the new cardiovascular and renal events occurrence were significantly decreased compared to patients displaying low values of these biomarkers.

CONCLUSION

The results of this study show that PCSK9 > 220 ng/mL was predictor for cardiovascular events, while EF < 50% was predictor for CKD progression to ESRD. PCSK9 > 220 ng/mL and hsCRP > 3 mg/L were associated with the occurrence of renal and cardiovascular events earlier.

Assessing the relationship between high-sensitivity C-reactive protein and kidney function employing mendelian randomization in a Japanese community based J-MICC Study

Background

Inflammation is thought to be a risk factor for kidney disease. However, whether inflammatory status is either a cause or an outcome of chronic kidney disease remains controversial. We aimed to investigate the causal relationship between high-sensitivity C-reactive protein (hs-CRP) and estimated glomerular filtration rate (eGFR) using Mendelian randomization (MR) approaches.

Methods

A total of 10,521 participants of the Japan Multi-institutional Collaborative Cohort Study was analyzed in this study. We used two-sample MR approaches (the inverse-variance weighted (IVW), the weighted median (WM), and the MR-Egger method) to estimate the effect of genetically determined hs-CRP on kidney function. We selected four and three hs-CRP associated single nucleotide polymorphisms (SNPs) as two instrumental variables (IV): IV_CRP and IV_Asian, based on SNPs previously identified in European and Asian populations. IV_CRP and IV_Asian explained 3.4% and 3.9% of the variation in hs-CRP, respectively.

Results

Using the IV_CRP, genetically determined hs-CRP was not significantly associated with eGFR in the IVW and the WM methods (estimate per 1 unit increase in ln(hs-CRP), 0.000; 95% confidence interval [CI], −0.019 to 0.020 and −0.003; 95% CI, −0.019 to 0.014, respectively). For IV_Asian, we found similar results using the IVW and the WM methods (estimate, 0.005; 95% CI, −0.020 to 0.010 and −0.004; 95% CI, −0.020 to 0.012, respectively). The MR-Egger method also showed no causal relationships between hs-CRP and eGFR (IV_CRP: −0.008; 95% CI, −0.058 to 0.042; IV_Asian: 0.001; 95% CI, −0.036 to 0.036).

Conclusion

Our two-sample MR analyses with different IVs did not support a causal effect of hs-CRP on eGFR.

Hyperhomocysteinemia Concurrent with Metabolic Syndrome Is Independently Associated with Chronic Kidney Disease among Community-Dwelling Adults in an Urban Korean Population

Elevated homocysteine (Hcy) levels and metabolic syndrome (MetS) are associated with chronic kidney disease (CKD). We investigated the combined effects of hyperhomocysteinemia (HHcy) and MetS on CKD among community-dwelling adults in an urban area of South Korea. We also identified the combination of HHcy and individual MetS components associated with the maximal risk of CKD. A retrospective cross-sectional study involving 19,311 health examinees between 2 January 2011 and 31 December 2015 was conducted. The participants were divided into four groups—namely, the HHcy−/MetS−, HHcy−/MetS+, HHcy+/MetS−, and HHcy+/MetS+ groups. CKD was defined as a low eGFR <60 mL/min/1.73 m² or albuminuria. The HHcy+/MetS+ group had a higher risk of CKD than the HHcy−/MetS+ group (odds ratio (OR): 1.750, p = 0.002 for males; OR: 3.224, p < 0.001 for females). The HHcy+/MetS+ group had a higher CKD risk than the HHcy+/MetS− group; however, the difference was not statistically significant (OR: 1.070, p = 0.712 for males; OR: 1.847, and p < 0.074 for females). HHcy concurrent with MetS increased the CKD risk. Among the combinations of HHcy and MetS components, the coexistence of HHcy and central obesity had the greatest effect on CKD. Therefore, the timely detection and treatment of HHcy and MetS are important for preventing CKD.

Main Risk Factors Related to Activities of Daily Living in Non-Dialysis Patients with Chronic Kidney Disease Stage 3-5: A Case-Control Study

Introduction

Elderly people are at increased risk of falls, disability and death due to reduced functional reserve, decline in multiple systems functions, which affects their activities of daily living (ADL) and eventually develop into frailty. The ADL assessment is conducive to early detection to avoid further serious situations. Previous studies on patients’ activities of daily living with chronic kidney disease (CKD) are mainly focused on dialysis patients. Little information is available on non-dialysis patients.

Patients and Methods

A total of 303 elderly patients with CKD stage 3–5 who were admitted to our hospital were selected. ADL evaluation was performed on patients at admission, with Barthel index (BI) as the evaluation tool. They were divided into two groups based on BI (≥60 and <60). Demographic information, lifestyle and clinical profile were collected. The risk factors related to ADL were analyzed by univariate and multivariate models.

Results

The data of 303 patients enrolled in this study were analyzed. The average age of patients was 84.48± 7.14 years and 62.05% were male. There were 88 patients (29.04%) in BI <60 group and 215 patients (70.96%) in the BI ≥60 group. The average age of subjects in the two groups was 87.47 ± 5.85 years and 83.26± 7.28 years, respectively. On univariate analysis, ADL impairment was associated with many factors, such as age, body mass index, blood lipid, heart rate, smoking history, Charlson comorbidity index (CCI), hemoglobin, serum albumin, BNP, eGFR, etc. Multivariate logistic regression showed that age (OR 1.08, 95% CI 1.00–1.17, P=0.0390), Charlson comorbidity index (OR 4.75, 95% CI 1.17–19.30, P=0.0295), and serum albumin (OR 0.80, 95% CI 0.70–0.92, P=0.0012) were the independent risk factors of ADL impairment.

Conclusion

Decline of ADL in CKD patients was independently correlated with age, Charlson comorbidity index and serum albumin. ADL and its influential factors in the elderly CKD patients deserve further attention.

Metabolic abnormalities, but not obesity per se, associated with chronic kidney disease in a Taiwanese population

BACKGROUND AND AIMS

It is inconclusive whether obesity itself or metabolic abnormalities are linked to chronic kidney disease (CKD). The aim of this study was to examine the association between different subtypes of obesity and metabolic abnormalities with CKD in adults.

METHODS AND RESULTS

This study enrolled 14,983 eligible subjects stratified into metabolically healthy normal weight (MHNW), metabolically healthy overweight (MHOW), metabolically healthy obesity (MHO), metabolically unhealthy normal weight (MUNW), metabolically unhealthy overweight (MUOW), and metabolically unhealthy obesity (MUO) according to body mass index and metabolic syndrome status (ATP-III criteria). The metabolic healthy phenotype was defined as the absence of both metabolic syndrome and any known diabetes, coronary artery disease, stroke, hypertension or dyslipidemia. Early and advanced CKD were defined as eGFR<60, proteinuria, or structural abnormalities as detected by renal sonography. The prevalence of CKD was 2.5, 3.0, 4.0, 10.6, 9.5, and 10.5% in subjects with MHNW, MHOW, MHO, MUNW, MUOW, and MUO, respectively. In the multivariate analysis, the MUNW (OR:2.22, P < 0.001), MUOW (OR:2.22, P < 0.001), and MUO (OR:2.45, P < 0.001) groups were associated with early CKD. For advanced CKD, the OR was 2.56 (P < 0.001), 2.31 (P < 0.001), and 3.49 (P < 0.001) in the MUNW, MUOW, and MUO groups, respectively. The associated risks of early and advanced CKD were not significant in the MHOW and MHO group. MUOW and MUO were associated with higher risk of CKD compared with MHOW and MHO after adjusting other variables.

CONCLUSIONS

Metabolic abnormalities, but neither overweight nor obesity, were associated with a higher risk of CKD in adults.

Reduction in Serum High-Sensitivity C-Reactive Protein Favors Kidney Outcomes in Patients with Impaired Fasting Glucose or Diabetes

OBJECTIVE

We aimed to evaluate whether the reduction in serum high-sensitivity C-reactive protein (hs-CRP) favors kidney outcomes.

METHODS

This study was a subanalysis including patients with impaired fasting glucose or diabetes of the Kailuan cohort study. The predictor was based on two consecutive visits of hs-CRP levels in 2006 and 2008. A total of 3924 patients with hs-CRP ≥ 3 mg/L in 2006 were divided into two groups according to whether the levels of hs-CRP were reduced in 2008: Group 1: no reduction: hs-CRP ≥ 3 mg/L in 2008; Group 2: reduction: hs-CRP < 3 mg/L in 2008. Kidney outcomes include kidney function decline and development and progression of proteinuria and were followed up until the end of 2015.

RESULTS

There were 3905, 2049, and 493 patients included into our analysis for the outcomes of kidney function decline and the development and progression of proteinuria, respectively. A total of 398, 297, and 47 events occurred after 5 years of follow-up, respectively. Cox regression revealed that patients with reduction in hs-CRP have lower risk of kidney function decline (HR 0.71, 95% CI 0.57-0.89, and P = 0.002) and development of proteinuria (0.77, 0.61-0.99, and P = 0.038) after controlling for potential confounders as compared to those with no reduction in hs-CRP levels.

CONCLUSIONS

Reduction in serum hs-CRP levels favors kidney outcomes in patients with impaired fasting glucose or diabetes.

Association between metabolic body composition status and risk for impaired renal function: A cross-sectional study

BACKGROUND

The risk for obesity-related disorders is proportional to the visceral region and had been observed to be highly related with impaired renal function. In the current study, we aimed to evaluate renal function impairment, according to sex, age, and different status of metabolic body composition.

METHODS

We retrospectively collected from the medical records the basic information and metabolic titers of Chinese adults (13,373 men and 10,175 women) who underwent health checkup from 2013 to 2016. The population was divided into four groups, according to metabolic body composition, including metabolic healthy norms-weight (MHNW), metabolic healthy obesity (MHO), metabolic unhealthy norms-weight (MUNW), and metabolic unhealthy obesity (MUO). The categorical data were compared among the groups and logistic regression analyses were conducted to investigate the association between metabolic body composition status and risk for renal function impairment.

RESULTS

Across all ages in both sexes, the odds ratios (OR) for renal function impairment were higher in the MHO, MUNW, and MUO groups than in the MHNW group, except for women <45 years old in the MUNW group. However, after adjustment, the trend was no longer significant in all groups under 45 years old. For individuals >45 years old, the relatively high risk for renal function impairment remained significantly associated with the MUNW group (OR 2.95, 95% CI 2.02-4.30 in men and OR 1.95, 95% CI 1.35-2.82 in women) and MUO group (OR 2.33, 95% CI 1.82-3.00 in men and OR 2.67, 95% CI 2.04-3.48 in women).

CONCLUSION

Impaired renal function was independently associated with the status of metabolic obesity. However, the trend was only observed in individuals >45 years old, with significant sex difference.

High sensitivity C-reactive protein as a predictive of intima-media thickness in patients with end-stage renal disease on regular hemodialysis

BACKGROUND

Several emerging problems of regular hemodialysis (HD) including cardiovascular complication or atherosclerosis formation caused by chronic inflammation. Intima-media thickness (IMT) of the carotid artery can be applied as a marker of atherosclerosis progression. This study was designed to identify the predictive of IMT progression among end-stage renal disease (ESRD) subject.

METHODS

This cohort study was performed at the Hemodialysis Unit of Dr. Kariadi Hospital and Telogorejo Hospital Semarang between October 2009 and April 2010. The study subjects were the ESRD patients with regular HD.

RESULTS

This study enrolled 78 subjects with regular HD, follow-up 6 months. The subjects which completed the study were divided into two groups that consist of IMT progressive group (n=53) and IMT non-progressive group (n=12). There were no differences between two groups according to age, gender, history of diabetes, blood pressure, duration of HD, urea, creatinine, blood glucose, HbA1C, cholesterol, triglyceride, HDL, uric acid, phosphate, calcium, homocysteine, and albumin. Subject with high-sensitive C-reactive protein (hsCRP) level >0.52 mg/L had an IMT progression. There was a correlation between hsCRP and the thickening of carotid artery wall after 6-month HD (RR=3.6; 95% CI=2.2-22.9). The subject with hsCRP level >9.00 mg/L after 6-month dialysis progress to thickening of carotid artery wall of >0.03 mm. There was a correlation between hsCRP level (cut-off point: 9.0 m/L) and the progression of the carotid artery wall (RR=2.1; 95% CI=1.3-3.37). Statistically, there was no correlation between IL-6-174 G/C gene and eNOS gene polymorphism with IMT progression.

CONCLUSION

hsCRP is a significant predictive of IMT progression at hemodialysis subject. IL -174 G/C gene and eNOS gene polymorphism are not significant predictive of IMT progression at hemodialysis subject.

Risk factors for peptic ulcer disease in patients with end-stage renal disease receiving dialysis

Background

Compared to the general population, patients with end-stage renal disease have more gastrointestinal symptoms and a higher prevalence of peptic ulcer. Risk factors for peptic ulcer disease in patients with end-stage renal disease, however, remain poorly defined. This study aims to better identify those risk factors.

Methods

We analyzed 577 patients with end-stage renal disease from 2004 to 2016. We excluded patients with life-threatening conditions. All patients underwent upper endoscopy. We analyzed patient medical records, medication history, and endoscopic findings. Independent sample t test, chi-square test, Fisher’s exact test, and multiple logistic regression analysis were used in statistical analyses.

Results

Of the 577 patients with end-stage renal disease, 174 had peptic ulcer disease (gastric or duodenal ulcer). Patients on hemodialysis had a higher prevalence of peptic ulcer disease than those on peritoneal dialysis. Patients with peptic ulcer disease had lower serum albumin level and higher blood urea nitrogen level than those without peptic ulcer disease. Positive scores on two or more nutritional indices (albumin, serum cholesterol, uric acid, and creatinine levels) were associated with peptic ulcer disease in end-stage renal disease.

Conclusion

Hemodialysis, hypoalbuminemia, and multiple malnutrition indices were associated with the prevalence of peptic ulcer disease in patients with end-stage renal disease receiving dialysis.

The impact of antihypertensive pharmacotherapy on interplay between protein-bound uremic toxin (indoxyl sulfate) and markers of inflammation in patients with chronic kidney disease

PURPOSE

Indoxyl sulfate (IS) is one of the most potent uremic toxins involved in chronic kidney disease (CKD) progression, induction of inflammation, oxidative stress, and cardiovascular diseases occurrence. It is proved that hypertension is a common CVD complication and a major death risk factor as well as contributes for decline in a renal function. The aim of our study was to investigate how implementing of antihypertensive therapy impact IS concentrations and the associations between IS and markers of renal function, inflammation and oxidative stress.

METHODS

Study was conducted on 50 patients diagnosed with CKD and hypertension, divided into three groups: without hypotensive therapy (CKD-NONE), hypotensive monotherapy (CKD-MONO), and hypotensive polypharmacotherapy (CKD-POLI), and 18 healthy volunteers. The markers of inflammation [interleukin-6, tumor necrosis factor-alpha (TNF-α), high-sensitive C-reactive protein (hs-CRP), neopterin, ferritin], oxidative status [superoxide dismutase (Cu/Zn-SOD), antibodies against oxidized low-density lipoprotein (oxLDL-abs)], and selectins were determinate using immunoenzymatic methods. IS levels were assayed using high-performance liquid chromatography and other parameters were analysed using routine laboratory techniques. Then cross-sectional analysis was performed.

RESULTS

Elevated levels of IS, indicators of kidney function, markers of inflammation and blood pressure values were observed in each CKD subgroups. There was no effect of antihypertensive therapy on IS levels between studied groups, as well as there was no clear relationship between IS and blood pressure values in each studied group. The positive associations between IS and Cu/Zn SOD, neopterin, hs-CRP, creatinine and neutrophils/lymphocytes ratio were observed in CKD-NONE and CKD-POLI subgroups. Additionally, in CKD-POLI group IS positively correlated with TNF-α, ferritin and neutrophils. In CKD-MONO group, IS was positively related to oxLDL-abs, neopterin, E-selectin and creatinine, whereas it was inversely associated with hs-CRP.

CONCLUSIONS

Our study showed for the first time that the antihypertensive therapy has no impact on IS levels in CKD patients with hypertension. However, the introduction of the antihypertensive therapy modified the dependencies between IS and the studied markers of kidney function, inflammation, oxidative stress and hematological parameters that are crucial for mortality and morbidity amongst the CKD patients with hypertension.

U-shaped association between serum albumin and development of chronic kidney disease in general hypertensive patients

BACKGROUND & AIMS

We aimed to examine the association between serum albumin (SAlb) and the development of chronic kidney disease (CKD), and examine any possible effect modifiers in general hypertensive patients with normal renal function and with no previous cardiovascular diseases (CVD).

METHODS

This is a post-hoc analysis (performed at May, 2018) of 12,621 hypertensive adults with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m² and SAlb ≥35.0 g/L from the renal sub-study of the China Stroke Primary Prevention Trial (CSPPT), conducted from May 2008 to August 2013. The primary outcome was development of CKD, defined as a decrease in eGFR of ≥30% and to a level of <60 mL/min/1.73 m²; or end stage renal disease.

RESULTS

The median follow-up duration was 4.4 years. Overall, the association between SAlb levels and risk of the primary outcome followed a U-shape. The risk of CKD development significantly decreased with the increment of SAlb (per g/L: OR = 0.92; 95% CI: 0.88-0.96) in participants with SAlb <51.4 g/L, and increased with the increment of SAlb (per g/L: OR = 1.06; 95%CI: 1.01-1.11) in participants with SAlb ≥51.4 g/L. Moreover, in participants with SAlb <51.4 g/L, the association between SAlb and CKD development remained significant in participants without proteinuria (per g/L: OR = 0.93; 95% CI: 0.88-0.99). The association between SAlb and CKD development was not significantly modified by age, sex, folic acid treatment, proteinuria, systolic blood pressure (SBP) at baseline and time-averaged SBP during the treatment period (all P-interactions>0.05).

CONCLUSIONS

There was a U-shaped association between SAlb levels and risk of CKD development among general hypertensive patients with normal renal function and without CVD, with a turning point at about 51.4 g/L.

Risk Factors of Renal Involvement Based on Different Manifestations in Patients with Ankylosing Spondylitis

BACKGROUND/AIMS

Renal involvement is one of the most common extra-articular complications caused by ankylosing spondylitis (AS). Most studies have focused on the incidence rate, clinical manifestation and pathology, while risk factors have hardly been investigated. Therefore, the objective of this study was to assess the risk factors of renal involvement in patients with AS.

METHODS

Clinical and biochemical data of 926 AS patients were collected. Based on the manifestations of renal involvement, patients were divided into three groups and the differences in clinical and biochemical characteristics were compared. A group with non-renal involvement served as a control. Multivariable logistic regression was used for analyzing risk factors of renal involvement in AS.

RESULTS

Of the 926 AS patients, 201 patients suffered from renal involvement. Moreover, female AS patients faced a higher risk of hematuria compared to male patients. As indicated by the data obtained from multivariate logistic regression analysis, gender, uric acid (UA), immunoglobulin A (IgA), and serum albumin (ALB) were found to be risk factors of renal involvement in AS. An increase in UA or IgA levels, or a decrease in ALB level can increase the risk of renal involvement with multiple manifestations (more than one manifestation of renal damage). According to our findings, no definite variable was identified as a risk factor of proteinuria in AS patients.

CONCLUSION

In AS patients, UA, IgA, and ALB levels can indicate the risk of renal involvement in AS patient and need to be paid special attention. Furthermore, women are subjected to a higher risk of hematuria.

GlycA, a marker of protein glycosylation, is related to albuminuria and estimated glomerular filtration rate: the ELSA-Brasil study

Background

Systemic inflammation has been implicated in several chronic diseases. GlycA is a new nuclear mass resonance (NMR) spectroscopy-derived biomarker of systemic inflammation that reflects protein glycosylation. We evaluated the association of GlycA with albuminuria and eGFR in the ELSA-Brasil Study.

Methods

The cross-sectional association between GlycA (automated NMR LipoProfile(®) test spectra, LabCorp, Raleigh, NC), and overnight 12 h–albuminuria and CKD-EPI eGFR was evaluated among 5050 participants.

Results

GlycA was higher among older, women, smokers, alcohol abstemious, obese and in those with diabetes, hypertension or dyslipidemia. In addition, both eGFR and albuminuria were associated to GlycA. In linear regression, GlycA was independently associated with log albuminuria (B 0.03; 95%CI 0.02–0.04, P < 0.0001, per 1sd increase) and inversely related to eGFR (B -0.53; 95%CI -0.99 – -0.07, P < 0.02), even after adjustments including hsCRP. In logistic regression, GlycA was independently related to the risk of A2 or A3 albuminuria (OR 1.42, 95%CI 1.27–1.57, p < 0.0001, per 1sd increase), of having an eGFR < 60 ml/min/1.73m² (OR 1.26, 95%CI 1.12–1.41, p = 0.0003, per 1 sd) or of a combined diagnosis of both conditions (OR 1.35, 95%CI 1.23–1.46, p < 0.0001, per 1 sd). In the ROC curve, GlycA had a higher AUC in comparison to hsCRP (AUC 0.67 vs. 0.62, p = 0.06) for the association with albuminuria A2 or A3.

Conclusions

The present study demonstrates that GlycA is associated with albuminuria and eGFR, independently of major risk factors for CKD progression, including (and with a stronger association than) hsCRP. GlycA should be further evaluated in CKD progression.

Impact of Renal Functional/Morphological Dynamics on the Calcification of Coronary and Abdominal Arteries in Patients with Chronic Kidney Disease

Aim: Fast-progressing vascular calcification (VC) is accompanied by renal atrophy and functional deterioration along with atherosclerosis in patients with chronic kidney disease (CKD). However, the relationship between VC progression and renal functional and/or morphological changes remains unclear.

Methods: We included 70 asymptomatic patients with CKD without hemodialysis in our study. To identify temporal variations, the coronary artery calcification score (CACS), abdominal aortic calcification index (ACI), and renal parenchymal volume index (RPVI) were determined via spiral computed tomography scans taken during the study. We investigated significant factors related to annualized variations of CACS (ΔCACS/y) and ACI (ΔACI/y).

Results: During the follow-up period (4.6 years), median values of CACS [in Agatston units (AU)] and ACI increased from 40.2 to 113.3 AU (p = 0.053) and from 13.2 to 21.7% (p = 0.036), respectively. Multivariate analysis revealed that CACS at baseline (p < 0.001) and diabetes mellitus (DM) status (p = 0.037) for ΔCACS/y and ACI at baseline (p = 0.017) and hypertension (HT) status (p = 0.046) for ΔACI/y were significant independent predictors. Furthermore, annualized RPVI variation was significantly related to both ΔCACS/y and ΔACI/y (R = −0.565, p < 0.001, and R = −0.289, p = 0.015, respectively). On the other hand, independent contributions of the estimated glomerular filtration rate (eGFR) and annualized eGFR variation to VC progression were not confirmed.

Conclusion: The degree of VC at baseline, DM, HT, and changes in renal volume, but not eGFR, had a strong impact on VC progression in patients with CKD.

Metabolically healthy obesity and incident chronic kidney disease: The role of systemic inflammation in a prospective study

OBJECTIVE

To investigate the association between the metabolically healthy obesity (MHO) phenotype and incident chronic kidney disease (CKD) in a Chinese population and whether systemic inflammation affects this association.

METHODS

A cohort study was performed with 2,491 Chinese adults. Body mass index ≥ 25.0 kg/m² was defined as obesity. CKD was defined as estimated glomerular filtration rate < 60 mL/min per 1.73 m² or urinary albumin-to-creatinine ratio ≥ 30 mg/g. High-sensitivity C-reactive protein (hsCRP) was used as a surrogate marker of systemic inflammation.

RESULTS

Over a median follow-up period of 3.9 years, 243 of 2,491 participants developed incident CKD (9.8%). Compared with metabolically healthy nonobesity (MHNO), MHO was associated with incident CKD (odds ratio [OR] = 1.65, 95% confidence interval [CI] 1.01-2.69), but not after adjustment for hsCRP. The MHO/hsCRP ≥ 0.20 mg/L group, but not the MHO/hsCRP < 0.20 mg/L group, had an increased OR for incident CKD (OR = 2.66, 95% CI 1.37-5.14), with the MHNO/hsCRP < 0.20 mg/L group as the reference.

CONCLUSIONS

MHO was significantly associated with incident CKD, and the level of systemic inflammation partially explained this association.

Investigation of Metabolic Factors Associated with eGFR Decline Over 1 Year in a Japanese Population without CKD

Aim: Early intervention before the progression of chronic kidney disease (CKD) is essential to prevent end-stage renal disease (ESRD) and cardiovascular complications. This study evaluated the correlation between metabolic and lifestyle-related factors and the decline of estimated glomerular filtration rate (eGFR) over 1 year in a Japanese population without CKD.

Methods: Subjects who received two consecutive annual health checkups from 2013 to 2015 were involved. Factors associated with eGFR decline were identified using multiple regression models.

Results: A total of 2531 subjects aged 58.9 ± 11.7 years old were included in this study. Baseline levels of HDL-C and ApoA1 correlated with the eGFR decline over 1 year defined as eGFR reduction rate of 15% or more and/or eGFR at the next year < 60 ml/min/m² (odds ratio (OR) 0.87 (per 10 mg/dl); 95% CI, 0.80–0.94; p = 0.0012, 0.90 (per 10 mg/dl); 0.86–0.96; p = 0.0004, respectively). A U-shaped relationship between the eGFR decline and HDL-C or ApoA1 levels was not observed in non-CKD population of this study. Metabolic syndrome was significantly associated with eGFR decline (OR 1.32; 1.04–1.67; p = 0.0205), although obesity-related factors did not show a significant correlation with eGFR decline over 1 year.

Conclusion: Low HDL-C and ApoA1 levels significantly correlated with eGFR decline in a short period of 1 year. Metabolic syndrome also showed a significant association with eGFR decline. This study suggests the importance of hypertension and low HDL-C in the metabolic syndrome effect on eGFR decline rather than obesity in non-CKD population.