Liou Cao

Prevalence of non-diabetic renal disease in patients with type 2 diabetes

It is important to differentiate proteinuria from non-diabetic renal diseases (NDRD) or diabetic nephropathy in diabetic patients. The purpose of our study was to evaluate the prevalence of NDRD. A retrospective analysis was performed on diabetic patients who had undergone renal biopsy during a 6-year period. Our study revealed a high prevalence of NDRD in the diabetic population. Sixty-nine patients were investigated, 52.2% were diagnosed as NDRD and 47.8% as DN. Focal segmental glomerulosclerosis was the most common lesion found in patients with NDRD. We found a relationship between DN and fasting blood glucose level, systolic blood pressure, diastolic blood pressure, LVMI, intima-media thickening (IMT), and the presence of carotid plaques. Patients with NDRD had a lower incidence of diabetic retinopathy (DR). The absence of DR to differentiate NDRD had a sensitivity of 72.7%, a specificity 91.7%, and an ROC=0.822. Fasting blood glucose level had a sensitivity and specificity of 93.9% and 75%, respectively. Similarly, the use of IMT had sensitivity and specificity of 90% and 75.8%, respectively. In this study, we determined that the absence of DR, a lower fasting blood glucose level, and IMT is useful in differentiating NDRD from DN in diabetic patients with overt proteinuria.

Circulating levels of asymmetric dimethylarginine are an independent risk factor for left ventricular hypertrophy and predict cardiovascular events in pre-dialysis patients with chronic kidney disease.

BACKGROUND Several studies have related the circulating level of asymmetric dimethylarginine (ADMA) to cardiac remodeling and cardiovascular (CV) events in end-stage renal disease (ESRD) patients. Studies investigating this relationship in patients with pre-dialysis chronic kidney disease (CKD) are lacking. METHODS We enrolled 76 CKD patients (age, 46.7+/-14.3 years, 39 females) and 15 controls (age, 40.1+/-18.5 years, 6 females). Clinical parameters, blood biochemistry and echocardiographic findings were recorded, and plasma ADMA concentrations measured by high-performance liquid chromatography-mass spectrometry (HPLC-MS). Patients were prospectively followed up for a median of 15 (range, 6-24) months. RESULTS Plasma ADMA was significantly elevated in CKD patients compared with controls (41.56+/-12.76 microg/mL vs 17.12+/-7.09 microg/mL, P<0.001), and correlated with the left ventricular mass index (LVMI) (r=0.597, P<0.001). During follow-up, 25 patients experienced new CV events and their plasma ADMA level was significantly elevated (48.27+/-13.70 vs 34.91+/-6.38 in CV event-free patients, P<0.001). Cox regression analysis further confirmed that ADMA was an independent risk factor for CVD (HR=1.175, 95%CI[1.070-1.290], P=0.001). CONCLUSION Similar to findings in ESRD patients, elevated circulating levels of ADMA may increase the risk of LVH and CV events in pre-dialysis CKD patients.

Better preservation of residual renal function in peritoneal dialysis patients treated with a low-protein diet supplemented with keto acids: a prospective, randomized trial

BACKGROUND While a low-protein diet may preserve residual renal function (RRF) in chronic kidney disease (CKD) patients before the start of dialysis, a high-protein intake is usually recommended in dialysis patients to prevent protein-energy wasting. Keto acids, which were often recommended to pre-dialysis CKD patients treated with a low-protein diet, had also been reported to be associated with both RRF and nutrition maintenance. We conducted a randomized trial to test whether a low-protein diet with or without keto acids would be safe and associated with a preserved RRF during peritoneal dialysis (PD). METHODS To assess the safety of low protein, we first conducted a nitrogen balance study in 34 incident PD patients randomized to receive in-centre diets containing 1.2, 0.9 or 0.6 g of protein/kg ideal body weight (IBW)/day for 10 days. Second, 60 stable PD patients [RRF 4.04 +/- 2.30 ml/ min/1.73 m(2), urine output 1226 +/- 449 ml/day, aged 53.6 +/- 12.8 years, PD duration 8.8 (1.5-17.8) months] were randomized to receive either a low- (LP: 0.6-0.8 g/kg IBW/day), keto acid-supplemented low- (sLP: 0.6-0.8 g/kg IBW/day with 0.12 g/kg IBW/day of keto acids) or high-protein (HP: 1.0-1.2 g/kg IBW/day) diet. The groups were followed for 1 year and RRF as well as nutritional status was evaluated serially. RESULTS A neutral or positive nitrogen balance was achieved in all three groups. RRF remained stable in group sLP (3.84 +/- 2.17 to 3.39 +/- 3.23 ml/min/1.73 m(2), P = ns) while it decreased in group LP (4.02 +/- 2.49 to 2.29 +/- 1.72 ml/min/1.73 m(2), P < 0.05) and HP (4.25 +/- 2.34 to 2.55 +/- 2.29 ml/min/1.73 m(2), P < 0.05). There was no change from baseline on nutritional status in any of the groups during follow-up. CONCLUSIONS A diet containing 0.6-0.8 g of protein/kg IBW/day is safe and, when combined with keto acids, is associated with an improved preservation of RRF in relatively new PD patients without significant malnutrition or inflammation.

Serum IL-18 Is Closely Associated with Renal Tubulointerstitial Injury and Predicts Renal Prognosis in IgA Nephropathy

Background. IgA nephropathy (IgAN) was thought to be benign but recently found it slowly progresses and leads to ESRD eventually. The aim of this research is to investigate the value of serum IL-18 level, a sensitive biomarker for proximal tubule injury, for assessing the histopathological severity and disease progression in IgAN. Methods. Serum IL-18 levels in 76 IgAN patients and 36 healthy blood donors were measured by ELISA. We evaluated percentage of global and segmental sclerosis (GSS) and extent of tubulointerstitial damage (TID). The correlations between serum IL-18 levels with clinical, histopathological features and renal prognosis were evaluated. Results. The patients were 38.85 ± 10.95 years old, presented with 2.61 (1.43∼4.08) g/day proteinuria. Serum IL-18 levels were significantly elevated in IgAN patients. Baseline serum IL-18 levels were significantly correlated with urinary protein excretion (r = 0.494, P = 0.002), Scr (r = 0.61, P < 0.001), and eGFR (r = −0.598, P < 0.001). TID scores showed a borderline significance with serum IL-18 levels (r = 0.355, P = 0.05). During follow-up, 26 patients (34.21%) had a declined renal function. Kaplan-Meier analysis found those patients with elevated IL-18 had a significant poor renal outcome (P = 0.03), and Cox analysis further confirmed that serum IL-18 levels were an independent predictor of renal prognosis (β = 1.98, P = 0.003).

Metabolic Syndrome Is Correlated With Carotid Atherosclerosis in Patients With Lupus Nephritis

Background:To investigate the prevalence of metabolic syndrome (MS) in patients with lupus nephritis (LN), and its correlation with carotid atherosclerosis. Methods:Two hundred ten patients with LN (age: 38.83 ± 12.41 years, 92.86% women) were enrolled. The control group included 150 lupus patients without nephritis and 200 age-matched healthy persons. The improved criteria in 2009 were used to calculate the prevalence of MS, and carotid artery ultrasound was used to detect plaque and intima-media thickness (IMT). The correlation between MS and carotid atherosclerosis in patients with LN was analyzed. Results:The prevalence of MS in patients with LN was 41.90%, which was significantly higher than that in lupus patients without nephritis (30.67%) and healthy controls (11.50%). LN patients with MS showed a significantly increased carotid plaque ratio (28.41% versus 17.21%, P < 0.05) and IMT value (0.74 ± 0.25 mm versus 0.64 ± 0.18 mm, P < 0.01). Stepwise multiple regression further confirmed that age (&bgr; = 0.026, P = 0.033), duration of disease (&bgr; = 0.057, P = 0.025) and MS (&bgr; = 0.074, P < 0.001) were independent risk factors that affected the carotid IMT value in patients with LN. Conclusions:The prevalence of MS was comparatively high in patients with LN and was significantly correlated with carotid atherosclerosis, indicating that MS screening might be useful in the prevention and treatment of carotid atherosclerosis in patients with LN.

High-Sensitivity C-Reactive Protein: An Independent Risk Factor for Left Ventricular Hypertrophy in Patients with Lupus Nephritis

Objective. To determine the prevalence of left ventricular hypertrophy (LVH) and its associated risk factors in lupus nephritis (LN) patients. Methods. 287 LN patients (age: 38.54 ± 13.31, 262 female) were recruited. Echocardiography and serum high-sensitivity C-reactive protein (hs-CRP) were measured. Their relationship was evaluated by univariate correlation analysis and multivariate regression analysis. Results. The prevalence of LVH in this cohort was 21.25% (n = 61). Serum hs-CRP level was significantly elevated in patients with LVH compared to those without (8.03 (3.22–30.95) versus 3.93 (1.48–9.48) mg/L, P < .01), and correlated with left ventricular mass index (LVMI) (r = 0.314, P = .001). Multivariate regression analysis further confirmed that hs-CRP was an independent risk factor (β = 0.338, P = .002) for LVH in patients with LN. Conclusions. Our findings demonstrated that serum hs-CRP level is independently correlated with LVMI and suggested that measurement of hs-CRP may provide important clinical information to investigate LVH in LN patients.

Comparison of Long-Term Outcomes between Peritoneal Dialysis Patients with Diabetes as a Primary Renal Disease or as a Comorbid Condition.

Objective To investigate the long-term outcomes of peritoneal dialysis (PD) patients with diabetes as primary renal disease and patients with diabetes as a comorbid condition. Methods All diabetic patients who commenced PD between January 1, 1995 and June 30, 2012 at Ren Ji Hospital, China were included. Patients were divided into diabetic nephropathy group (DN group) and non-diabetic nephropathy group (NDN group) according to their diagnosis of primary renal disease at the initiation of PD. They were followed until death, cessation of PD, transferred to other centers or to the end of study (June 30, 2013). Outcomes were analyzed by Kaplan-Meier method and Cox regression models. Results A total of 163 diabetic patients were enrolled in the study, including 121 (74.2%) in DN group and 42 (25.8%) in NDN group. The 1-, 2-, 3- and 5-year patient survival rates were 89%, 78%, 66% and 51% for DN group, and 85%, 63%, 53% and 25% for NDN group, respectively. Kaplan-Meier analysis showed that patients in NDN group had a worse patient survival compared with DN group (log rank 4.830, P=0.028). Patients in NDN group had a marginally shorter peritonitis-free period (log rank 3.297, P=0.069), however, there was no significant difference in technique survival (log rank 0.040, P=0.841). Multivariate Cox regression analysis showed that older age (HR 1.047, 95% CI 1.022-1.073, p<0.001), cardiovascular disease comorbidity (HR 2.200, 95% CI 0.1.269-3.814, P=0.005) and diabetes as a comorbidity condition (HR 1.806, 95% CI 1.003-3.158, P=0.038) were the independent predictors of increased mortality. Conclusions PD patients with diabetes as a comorbidity had an inferior patient survival compared to those with diabetic nephropathy, and closer monitoring and extra attention in the former subgroup of patients are therefore warranted.

Possible role of IL-6 and TIE2 gene polymorphisms in predicting the initial high transport status in patients with peritoneal dialysis: an observational study

Objectives The aim of this study was to investigate the effect of interleukin (IL)-6 and TIE2 gene polymorphisms on baseline peritoneal transport property. Design An observational study. Setting Renji Hospital in Shanghai, China. Participants This study included 220 patients with continuous ambulatory peritoneal dialysis (PD). Outcome measures Patients were divided into 2 groups based on the results of an initial peritoneal equilibration test performed within 3 months of starting PD therapy: group 1 consisted of low/low average transporters (n=123), and group 2 consisted of high/high average transporters (n=97). We genotyped TIE2 and IL-6 polymorphisms and analysed their effects on baseline transport status. Results The genotype AT in IL-6 Rs13306435 and the genotype CC in TIE2 Rs639225 were both negatively associated with a higher initial peritoneal transport status (IL-6 Rs13306435: OR=0.408, 95% CI 0.227 to 0.736; TIE2 Rs639225: OR=0.188, 95% CI 0.044 to 0.806). Conclusions IL-6 and TIE2 polymorphisms are associated with baseline peritoneal transport property.

Hyperleptinaemia, insulin resistance and survival in peritoneal dialysis patients

The aim of this study was to clarify the relationship between insulin resistance (IR) and glucose and lipid metabolism in peritoneal dialysis (PD) patients. The study also investigated the prognostic factors for survival in long‐term peritoneal dialysis patients.

Low-Protein Diet Supplemented with Keto Acids Is Associated with Suppression of Small-Solute Peritoneal Transport Rate in Peritoneal Dialysis Patients

Objective. We investigate whether low-protein diet would show benefits in suppressing peritoneal transport rate in peritoneal dialysis (PD) patients. Methods. This is a supplemented analysis of our previously published trial, which randomized 60 PD patients to receive low- (LP: dietary protein intake of 0.6–0.8 g/kg/d), keto-acid-supplemented low- (sLP: 0.6–0.8 g/kg/d with 0.12 g/kg/d of keto acids), or high- (HP: 1.0–1.2 g/kg/d) protein diet and lasted for one year. In this study, the variations of peritoneal transport rate were assessed. Results. While baseline D/Pcr (dialysate-to-plasma concentration ratio for creatinine at 4 hour) and D/D0glu (dialysate glucose at 4 hour to baseline dialysate glucose concentration ratio) were similar, D/Pcr in group sLP was lower, and D/D0glu was higher than those in the other two groups (P < 0.05) at 12th month. D/D0glu increased (P < 0.05), and D/Pcr tended to decrease, (P = 0.071) in group sLP. Conclusions. Low-protein diet with keto acids may benefit PD patients by maintaining peritoneum at a lower transport rate.