Serum Ceruloplasmin Level as a Predictor for the Progression of Diabetic Nephropathy in Korean Men with Type 2 Diabetes Mellitus

Novel Biomarkers for the diagnosis of diabetic nephropathy

Diabetes mellitus and its complications are a known public health problem nowadays. Diabetic nephropathy is one of the main complications and the result of multiple mechanisms, including: activation of the renin-angiotensin-aldosterone system, formation of advanced glycation end products and chronic inflammation that led to glomerular and tubulo-interstitial damage producing mesangial expansion and glomerulosclerosis, which finally results in chronic kidney disease. Early detection of diabetic nephropathy is essential for adequate intervention to stop, or at least slow down its progression. Multiple markers have been described, not only the classic ones such as serum creatinine, urea, and albuminuria, but at this point also novel biomarkers such as neutrophil gelatinase-associated lipocalin, tumor necrosis factor 1 receptor and monocyte chemoattractant protein-1, among others. The aim of this article was to provide an update review of the role of biomarkers in the diagnosis of diabetic nephropathy.

In-depth urinary and exosome proteome profiling analysis identifies novel biomarkers for diabetic kidney disease

Diabetic kidney disease (DKD) is a major microvascular complication of type 2 diabetes mellitus (T2DM). Monitoring the early diagnostic period and disease progression plays a crucial role in treating DKD. In this study, to comprehensively elucidate the molecular characteristics of urinary proteins and urinary exosome proteins in type 2 DKD, we performed large-scale urinary proteomics (n=144) and urinary exosome proteomics (n=44) analyses on T2DM patients with albuminuria in varying degrees. The dynamics analysis of the urinary and exosome proteomes in our study provides a valuable resource for discovering potential urinary biomarkers in patients with DKD. A series of potential biomarkers, such as SERPINA1 and transferrin (TF), were detected and validated to be used for DKD diagnosis or disease monitoring. The results of our study comprehensively elucidated the changes in the urinary proteome and revealed several potential biomarkers reflecting the progression of DKD, which provide a reference for DKD biomarker screening.

Change in pulmonary function tests and their relation to the serum levels of ceruloplasmin, copper and superoxide dismutase in patients suffering from Type-1 and Type-2 diabetes

Objective

To correlate the serum levels of ceruloplasmin (Cp), copper (Cu), and superoxide dismutase (SOD) with pulmonary function tests (PFTs) in non-diabetics (controls) and patients suffering from Type-1 and Type- 2 diabetes.

Methods

The comparative cross-sectional study of 348 participants was performed at the Baqai Institute of Diabetes and Endocrinology (BIDE) - Karachi, Pakistan, from February 2019 to September 2020. Individuals having diabetes-related complications, asthma, chronic obstructive pulmonary disease, chest infection, pregnant women and smokers were excluded. A total of 348 participants were included into three groups after signing informed consent. The control group had 107 non-diabetic participants, with an age range of 6 to 60 years. The diagnosed T1D group (n=107) had an age range of 6 to 25 years. While diagnosed T2D group (n=134) had an age range of 26 to 60 years. During the fasting state, anthropometric parameters, blood pressure, spirometry, and a venous blood sample (5ml) were collected to measure serum Cp, serum Cu, serum SOD, and HbA1c levels by using commercially available kits. The SPSS, version 21, was used for data analysis.

Results

The reduced FVC (p-value <0.001), FEV1 (p-value <0.001), and PEFR (p-value <0.001) were found in both groups of diabetes. However, the lower levels of serum Cu (p-value <0.001), SOD (p-value <0.001), and significantly increased values of FEV1/ FVC (p-value <0.001) and Cp levels (p-value 0.030) were found only in T2D group as compared to T1D and controls. The study found no significant correlation of PFTs and serum Cp, Cu, and SOD levels in patients suffering from T1D and T2D.

Conclusion

Hyperglycemia leads to more non-enzymatic glycosylation of tissue proteins that reflects reduced PFTs and increased Cp; particularly in T2D, which may alter lung tissue's physiology. Moreover, the study showed no correlation of PFTs with the Cp, Cu, and SOD in patients suffering from T1D and T2D.

Novel biomarkers for prognosticating diabetic kidney disease progression

The global burden of diabetic kidney disease (DKD) is escalating, and it remains as a predominant cause of the end-stage renal disease (ESRD). DKD is associated with increased cardiovascular disease and morbidity in all types of diabetes. Prediction of progression with albuminuria and eGFR is challenging in DKD, especially in non-proteinuric DKD patients. The pathogenesis of DKD is multifactorial characterized by injury to all components of the nephron, whereas albuminuria is an indicator of only glomerular injury. The limits in the diagnostic and prognostic value of urine albumin demonstrate the need for alternative and clinically significant early biomarkers, allowing more targeted and effective diabetic treatment, to reduce the burden of DKD and ESRD. Identification of biomarkers, based on multifactorial pathogenesis of DKD can be the crucial paradigm in the treatment algorithm of DKD patients. This review focuses on the potential biomarkers linked to DKD pathogenesis, particularly with the hope of broadening the diagnostic window to identify patients with different stages of DKD progression.

A correlative study of copper, ceruloplasmin, iron, total iron binding capacity and total antioxidant capacity in diabetic nephropathy

Introduction and Aim:   Diabetic nephropathy is the common cause of final stage of kidney disease. Studies on trace elements and oxidant-antioxidant status in diabetes mellitus are required for establishing the mechanisms involved in pathogenesis of diabetic complications, and also to establish biomarkers of diabetic nephropathy in addition to the conventional markers. The present study aimed to assess and correlate the blood levels of copper, iron, ceruloplasmin, total iron binding capacity (TIBC) and total antioxidant capacity (TAC) in diabetic nephropathy patients in comparison to diabetic individuals without complications and normal healthy controls.   Materials and Methods: The study subjects were, diabetic patients with nephropathy (group 1), diabetic patients without complications (group 2), and healthy controls (group 3). In the serum samples of all study subjects levels of copper, iron, ceruloplasmin, TIBC and TAC were estimated by standard spectrophotometric methods.   Results: Levels of copper, ceruloplasmin, iron and TIBC in serum were significantly higher and TAC was lower in diabetic patients when compared to controls, and more pronounced changes were seen in diabetic nephropathy patients when compared to diabetic patients with no complications. There was significant positive correlation among glycated hemoglobin, copper, iron and microalbumin in diabetic patients with or without nephropathy. Serum Total antioxidant capacity showed significant negative correlation with HbA1c, microalbuminuria, copper, and iron in diabetic patients with and without nephropathy.   Conclusion: Serum levels of trace elements could serve as diagnostic and prognostic biomarkers of diabetic nephropathy complimentary to microalbuminuria and glycated haemoglobin. Monitoring the trace elements and oxidative stress biomarkers in diabetic patients could be beneficial to prevent oxidative stress and pathogenesis of diabetic complications.

The nephropathy of sickle cell trait and sickle cell disease

Sickle cell syndromes, including sickle cell disease (SCD) and sickle cell trait, are associated with multiple kidney abnormalities. Young patients with SCD have elevated effective renal plasma flow and glomerular filtration rates, which decrease to normal ranges in young adulthood and subnormal levels with advancing age. The pathophysiology of SCD-related nephropathy is multifactorial - oxidative stress, hyperfiltration and glomerular hypertension are all contributing factors. Albuminuria, which is an early clinical manifestation of glomerular damage, is common in individuals with SCD. Kidney function declines more rapidly in individuals with SCD than in those with sickle cell trait or in healthy individuals. Multiple genetic modifiers, including APOL1, HMOX1, HBA1 and HBA2 variants are also implicated in the development and progression of SCD-related nephropathy. Chronic kidney disease and rapid decline in estimated glomerular filtration rate are associated with increased mortality in adults with SCD. Renin-angiotensin-aldosterone system inhibitors are the standard of care treatment for albuminuria in SCD, despite a lack of controlled studies demonstrating their long-term efficacy. Multiple studies of novel therapeutic agents are ongoing, and patients with SCD and kidney failure should be evaluated for kidney transplantation. Given the high prevalence and severe consequences of kidney disease, additional studies are needed to elucidate the pathophysiology, natural history and treatment of SCD-related nephropathy.

Molecular Functions of Ceruloplasmin in Metabolic Disease Pathology

Ceruloplasmin (CP) is a multicopper oxidase and antioxidant that is mainly produced in the liver. CP not only plays a crucial role in the metabolic balance of copper and iron through its oxidase function but also exhibits antioxidant activity. In addition, CP is an acute-phase protein. In addition to being associated with aceruloplasminemia and neurodegenerative diseases such as Wilson's disease, Alzheimer's disease, and Parkinson's disease, CP also plays an important role in metabolic diseases, which are caused by metabolic disorders and vigorous metabolism, mainly including diabetes, obesity, hyperlipidemia, etc. Based on the physiological functions of CP, we provide an overview of the association of type 2 diabetes, obesity, hyperlipidemia, coronary heart disease, CP oxidative stress, inflammation, and metabolism of copper and iron. Studies have shown that metabolic diseases are closely related to systemic inflammation, oxidative stress, and disorders of copper and iron metabolism. Therefore, we conclude that CP, which can reduce the formation of free radicals in tissues, can be induced during inflammation and infection, and can correct the metabolic disorder of copper and iron, has protective and diagnostic effects on metabolic diseases.

Prospection of plasma proteins as biomarkers for diabetes mellitus monitoring

Purpose

This prospective study aimed to detect and identify plasma proteins differentially expressed between groups of Brazilian diagnosed with type 1 (T1DM), type 2 (T2DM) diabetes with good and poor glycemic control and the non-diabetic group denominated control group (CG).

Methods

Patients with T1DM and T2DM were subdivided according to their glycated haemoglobin (HbA_1c) level: ≥ 53 mmol/mol and < 53 mmol/mol. Each subgroup was composed of ten subjects (n = 10). The plasma from each subgroup was pooled and depleted of albumin and IgG. The reminiscent proteins were quantified and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The relative volume of protein bands was determined by densitometry analysis, and those with differential abundance were identified by MALDI-TOF mass spectrometry.

Results

Alpha 2 - Macroglobulin (AMG) was 1.3-fold more abundant in T1DM with HbA_1c ≥ 53 mmol/mol and < 53 mmol/mol and 1.4-fold more abundant in T2DM with HbA_1c ≥ 53 mmol/mol compared to CG. Ceruloplasmin (Cp) and Haptoglobin (Hp) were overexpressed above 1.5-fold in all DM subgroups. Cp in T1DM and Hp in both types of DM were more expressed in HbA_1c ≥ 53 mmol/mol than <53 mmol/mol. Apolipoprotein A-I (Apo A-I) was upregulated only in T2DM subgroups.

Conclusion

In summary, three positive acute-phase proteins, AMG, Cp and Hp were more abundant in diabetic individuals regardless of the diabetes type. The highest Hp abundance in both types of DM with HbA_1c ≥ 53 mmol/mol, reinforces Hp as a possible biomarker associated with diabetic complications.

Evaluation of Serum Ceruloplasmin Levels as a Biomarker for Oxidative Stress in Patients With Diabetic Retinopathy

Background

Elevated serum ceruloplasmin is a biomarker for oxidative stress. Diabetes mellitus (DM) is known to be a state of oxidative stress which causes complications of DM including diabetic retinopathy (DR). The role of ceruloplasmin in DR is still unclear.

Methods

Ninety patients of DM were included as cases and after evaluation sub-grouped as those with no DR, non-proliferative DR (NPDR) and proliferative DR (PDR). Serum ceruloplasmin levels were tested in all cases as well as in equal numbers of age and sex-matched controls without DM. Statistical analysis was done with p<0.05 taken as significant.

Results

 Serum ceruloplasmin was significantly higher among cases as compared to controls (1222.82±306.15 IU/L versus 868.38±198.80 IU/L, p<0.01). There was no statistical difference between serum ceruloplasmin values in No DR, NPDR and PDR. On receiver operator characteristic curve (ROC) analysis for serum ceruloplasmin as a test for discriminating various parameters, it was seen that serum ceruloplasmin was a good test for discriminating DM from no DM (area under receiver operator characteristic {AUROC}=0.814, 95% CI=0.749-0.868, p<0.0001) with a cut point of >1093 IU/L yielding a sensitivity of 63.33% and specificity of 87.78%. Ceruloplasmin as a test was not found to significantly discriminate DR (total) from no DR, NPDR from no DR, PDR from no DR and PDR from NPDR.

Conclusion

Serum ceruloplasmin levels are significantly raised in patients with DM. However, serum ceruloplasmin levels do not correlate with DR severity.

Risk assessment for foot ulcers among Tunisian subjects with diabetes: a cross sectional outpatient study

BACKGROUND

Diabetic foot is an underestimated and redoubtable diabetes complication. The aims of our study were to assess diabetic foot ulcer risk factors according to International Working Group on the Diabetic Foot (IWGDF) classification, stratify patients into risk categories and identify factors associated with higher-risk grade.

METHODS

Cross-sectional setting over a period of 07 months, patients were randomly selected from the diabetic outpatients attending our unit of diabetology. Questionnaire and clinical examination were made by the same physician. Patients free of active foot ulcer were included.

RESULTS

Among 230 patients evaluated, 10 had an active foot ulcer and were excluded. Five patients (2.27%) had a history of foot ulcer and 3(1.36%) had a lower-limb amputation. Sensory neuropathy, as measured by the 5.07(10 g) Semmes-Weinstein monofilament testing, was present in 23.63% of patients, whereas 36.82% had a peripheral arterial disease based on clinical findings, and 43.63% had foot deformities. According to the IWGDF classification, Group 0: 72.72%, Group 1: 5.9%, Group 2: 17.73% and Group 3: 3.63%. After univariate analysis, patients in higher-risk groups were significantly more often female, had higher age and BMI, longer diabetes duration, elevated waist circumference, low school level, retinopathy and hyperkeratosis. Multivariate logistic regression analysis identified 3 significant independent factors associated with high-risk groups: retinopathy (OR = 2.529, CI95 [1.131-5.655], p = 0.024), hyperkeratosis (OR = 2.658, CI95 [1.222-5.783], p = 0.014) and school level (OR = 0.489, CI95 [0.253-9.44], p = 0.033).

CONCLUSIONS

Risk factors for foot ulceration were rather common in outpatients with diabetes. The screening of patients at risk for foot ulceration should start early, integrated with sustainable patient education.

Metalloproteins and apolipoprotein C: candidate plasma biomarkers of T2DM screened by comparative proteomics and lipidomics in ZDF rats

Background

Early diagnosis of type 2 diabetes mellitus (T2DM) is still difficult. Screening of plasma biomarkers has great significance of optimizing diagnosis and predicting the complications of T2DM.

Methods

We used a special diet, Purina #5008, to induce diabetes in Zucker leptin receptor gene-deficient rats (fa/fa) to establish Zucker diabetic fatty (ZDF) rats, simulating the early stage of T2DM. The differentially expressed proteins (DEP) and lipids (DEL), as potential biomarkers, were screened to compare the plasma expression levels in ZDF rats and their basic diet-fed wild-type controls (fa/+) by Tandem Mass Tags (TMT) and liquid chromatography-tandem mass spectrometry.

Results

These two groups had different plasma proteins and lipids profiles consisting of 84 DEPs and, 179 DELs identified in the positive ion mode and 178 DELs in the negative ion mode, respectively. Enrichment analysis of these different indicators showed that oxidative stress, insulin resistance and metabolic disorders of glycan and lipid played an important role in generating the difference. Some markers can be used as candidate biomarkers in prediction and treatments of T2DM, such as ceruloplasmin, apolipoprotein C-I, apolipoprotein C-II and apolipoprotein C-IV.

Conclusion

These plasma differences help to optimize the diagnosis and predict the complications of T2DM, although this remains to be verified in the crowd. Trace elements related-metalloproteins, such as ceruloplasmin, and lipid metabolism and transport-related apolipoprotein C are expected to be candidate biomarkers of T2DM and should be given more attention.

Oxidative Stress in Peritoneal Dialysis Patients: Association with the Dialysis Adequacy and Technique Survival

Introduction:

Increased oxidative stress is suggested as one of the possible mechanisms of structural and functional damage to the peritoneal membrane in peritoneal dialysis patients. But there are few available data on the association of oxidative stress with peritoneal dialysis adequacy and technique survival. The present study was undertaken to investigate the association of oxidative stress biomarkers with the peritoneal dialysis adequacy and technique survival.

Methods:

This prospective single-center observational study was conducted between January 2010 and May 2015. Adequacy of dialysis, malondialdehyde levels in the serum and erythrocytes (as an indicator of lipid peroxidation), the concentration of ceruloplasmin, transferrin, and sulfhydryl groups in the blood, and total peroxidase activity in erythrocyte (as indicators of antioxidant system) were determined in 44 stable ambulatory non-diabetic peritoneal dialysis patients.

Results:

The follow-up period was 3 years. We identified a negative correlation between the serum level of malondialdehyde in the patients and total weekly Kt/V. Peritoneal weekly CrCl was positively correlated with the levels of transferrin, total peroxidase activity, and SH– groups. Daily peritoneal ultrafiltration had a positive correlation with the total peroxidase activity and the serum transferrin levels. The results of the Kaplan–Meier analysis and the log-rank test also demonstrated a significant difference in the cumulative technique survival rate between the patients with ceruloplasmin level ≤0.19 g/l and ≥0.2 g/l.

Conclusions:

The results mentioned above could be considered as one of the ways to explain better technique survival in PD patients.

Long-term expression of glomerular genes in diabetic nephropathy

Background

Although diabetic nephropathy (DN) is the most common cause for end-stage renal disease in western societies, its pathogenesis still remains largely unclear. A different gene pattern of diabetic and healthy kidney cells is one of the probable explanations. Numerous signalling pathways have emerged as important pathophysiological mechanisms for diabetes-induced renal injury.

Methods

Glomerular cells, as podocytes or mesangial cells, are predominantly involved in the development of diabetic renal lesions. While many gene assays concerning DN are performed with whole kidney or renal cortex tissue, we isolated glomeruli from black and tan, brachyuric (BTBR) obese/obese (ob/ob) and wildtype mice at four different timepoints (4, 8, 16 and 24 weeks) and performed an mRNA microarray to identify differentially expressed genes (DEGs). In contrast to many other diabetic mouse models, these homozygous ob/ob leptin-deficient mice develop not only a severe type 2 diabetes, but also diabetic kidney injury with all the clinical and especially histologic features defining human DN. By functional enrichment analysis we were able to investigate biological processes and pathways enriched by the DEGs at different disease stages. Altered expression of nine randomly selected genes was confirmed by quantitative polymerase chain reaction from glomerular RNA.

Results

Ob/ob type 2 diabetic mice showed up- and downregulation of genes primarily involved in metabolic processes and pathways, including glucose, lipid, fatty acid, retinol and amino acid metabolism. Members of the CYP4A and ApoB family were found among the top abundant genes. But more interestingly, altered gene loci showed enrichment for processes and pathways linked to angioneogenesis, complement cascades, semaphorin pathways, oxidation and reduction processes and renin secretion.

Conclusion

The gene profile of BTBR ob/ob type 2 diabetic mice we conducted in this study can help to identify new key players in molecular pathogenesis of diabetic kidney injury.

Changes in Trace Elements During Early Stages of Chronic Kidney Disease in Type 2 Diabetic Patients

Trace elements can influence glucose metabolism and be related to oxidative stress in type 2 diabetes mellitus. Moreover, trace elements play important roles in the nephrotic complications of these patients. Nevertheless, few investigations have been made into the changes in the levels of trace elements in diabetic patients at various stages of chronic kidney disease (CKD). The aims of this present study were to determine the levels of some important trace elements in diabetic patients during the early stages of CKD and to identify the relationship between these elements and CKD progression in type 2 diabetic patients. One hundred and forty-eight type 2 diabetic patients with chronic kidney diseases were recruited into this study. The subjects were grouped into four stages (1, 2, 3a, 3b) of CKD, according to their urine protein levels and estimated glomerular filtration rates (eGFRs). The levels of serum zinc and iron exhibited a statistically significant decreasing trend (P trend = 0.032 and 0.047, respectively) from stage 1 to stage 3b after adjustment for age, gender, smoking, alcohol consumption, education, hypertension, and body mass index. The other tested elements, including copper, magnesium, selenium, chromium, and manganese, did not display any significant trends upon proceeding from stage 1 to stage 3b. Thus, serum zinc and iron appear to be useful markers when evaluating the early progression of CKD in type 2 diabetic patients.

Recent advancements in biopolymer and metal nanoparticle-based materials in diabetic wound healing management

Currently, diabetes mellitus (DM) accelerated diabetic foot ulcer (DFU) remains vivacious health problem related with delayed healing and high amputation rates which leads to enormous clinical obligation. Keeping in view of the foregoing, researchers have been made in their efforts to develop novel materials which accelerate delayed wound healing in the diabetic patient and reduce the adversative influences of DFUs. The most prominent materials used for the wound healing application have biocompatibility, low cytotoxicity, excellent biodegradable properties, and antimicrobial activity properties. Utilization of nanoparticles has emerged as a protruding scientific and technological revolution in controlling DFUs. Biopolymers in combination with bioactive nanoparticles having antimicrobial, antibacterial, and anti-inflammatory properties have great potential in wound care to enhance the healing process of diabetic wound infectious. Combination of antibacterial nanoparticles like silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), copper nanoparticles (CuNPs) etc. with polymeric matrix could efficiently inhibit bacterial growth and at the same time fastens the healing process of a wound. This review briefed the recent development of different natural polymers and antibacterial nanoparticles to mitigate the diabetes mellitus based DFU.

The Divalent Elements Changes in Early Stages of Chronic Kidney Disease

As the glomerular filtration rate (GFR) decreases, it can cause imbalance in some divalent elements. These imbalances can cause increased oxidative stress in patients with renal impairment. The aim of present study was to investigate the changes of these divalent elements with CKD progression. One hundred and ninety-four patients with chronic kidney diseases (CKD) were divided into five stages, stage 1, 2, 3a, 3b, 4, and were recruited into this study. The divalent elements, calcium, magnesium, phosphorus, as well as iron, zinc, and copper were determined in clinical chemistry analyzer. Higher CKD stages were found to be associated with increased levels of phosphorus and copper; P_trend values were 0.002 and 0.004, respectively. Also, higher CKD stages were associated with decreased levels of zinc; P_trend value was 0.002, after adjustment for age, gender, smoke, education, diabetes, hypertension, and BMI. Decreased levels of zinc and elevated levels of phosphorus and copper might increase the oxidative stress and complications in CKD patients. Future randomized studies are needed to show whether adjusting dietary intake of phosphorus, copper, and zinc might affect the progression of CKD.

Incidence of chronic kidney disease among people with diabetes: a systematic review of observational studies

AIMS

The aim was to systematically review published articles that reported the incidence of chronic kidney disease among people with diabetes.

METHODS

A systematic literature search was performed using MEDLINE, Embase and CINAHL databases. The titles and abstracts of all publications identified by the search were reviewed and 10 047 studies were retrieved.

RESULTS

A total of 71 studies from 30 different countries with sample sizes ranging from 505 to 211 132 met the inclusion criteria. The annual incidence of microalbuminuria and albuminuria ranged from 1.3% to 3.8% for Type 1 diabetes. For Type 2 diabetes and studies combining both diabetes types, the range was from 3.8% to 12.7%, with four of six studies reporting annual rates between 7.4% and 8.6%. In studies reporting the incidence of eGFR < 60 ml/min/1.73 m² using the Modification of Diet on Renal Disease (MDRD) equation, apart from one study which reported an annual incidence of 8.9%, the annual incidence ranged from 1.9% to 4.3%. The annual incidence of end-stage renal disease ranged from 0.04% to 1.8%.

CONCLUSIONS

The annual incidence of microalbuminuria and albuminuria is ~ 2-3% in Type 1 diabetes, and ~ 8% in Type 2 diabetes or mixed diabetes type. The incidence of developing eGFR < 60 ml/min/1.73 m² is ~ 2-4% per year. Despite the wide variation in methods and study design, within a particular category of kidney disease, there was only modest variation in incidence rates. These findings may be useful in clinical settings to help understand the risk of developing kidney disease among those with diabetes.

Global epidemiology of diabetic foot ulceration: a systematic review and meta-analysis †

Diabetic foot is a severe public health issue, yet rare studies investigated its global epidemiology. Here we performed a systematic review and meta-analysis through searching PubMed, EMBASE, ISI Web of science, and Cochrane database. We found that that global diabetic foot ulcer prevalence was 6.3% (95%CI: 5.4-7.3%), which was higher in males (4.5%, 95%CI: 3.7-5.2%) than in females (3.5%, 95%CI: 2.8-4.2%), and higher in type 2 diabetic patients (6.4%, 95%CI: 4.6-8.1%) than in type 1 diabetics (5.5%, 95%CI: 3.2-7.7%). North America had the highest prevalence (13.0%, 95%CI: 10.0-15.9%), Oceania had the lowest (3.0%, 95% CI: 0.9-5.0%), and the prevalence in Asia, Europe, and Africa were 5.5% (95%CI: 4.6-6.4%), 5.1% (95%CI: 4.1-6.0%), and 7.2% (95%CI: 5.1-9.3%), respectively. Australia has the lowest (1.5%, 95%CI: 0.7-2.4%) and Belgium has the highest prevalence (16.6%, 95%CI: 10.7-22.4%), followed by Canada (14.8%, 95%CI: 9.4-20.1%) and USA (13.0%, 95%CI: 8.3-17.7%). The patients with diabetic foot ulcer were older, had a lower body mass index, longer diabetic duration, and had more hypertension, diabetic retinopathy, and smoking history than patients without diabetic foot ulceration. Our results provide suggestions for policy makers in deciding preventing strategy of diabetic foot ulceration in the future. Key messages Global prevalence of diabetic foot is 6.3% (95%CI: 5.4-7.3%), and the prevalence in North America, Asia, Europe, Africa and Oceania was 13.0% (95%CI: 10.0-15.9%), 5.5% (95%CI: 4.6-6.4%), 5.1% (95%CI: 4.1-6.0%), 7.2% (95%CI: 5.1-9.3%), and 3.0% (95% CI: 0.9-5.0%). Diabetic foot was more prevalent in males than in females, and more prevalent in type 2 diabetic foot patients than in type 1 diabetic foot patients. The patients with diabetic foot were older, had a lower body mass index, longer diabetic duration, and had more hypertension, diabetic retinopathy, and smoking history than patients without diabetic foot.

Serum Vascular Adhesion Protein-1 Predicts End-Stage Renal Disease in Patients with Type 2 Diabetes

BACKGROUND

Diabetes is the leading cause of end-stage renal disease (ESRD) worldwide. Vascular adhesion protein-1 (VAP-1) participates in inflammation and catalyzes the deamination of primary amines into aldehydes, hydrogen peroxide, and ammonia, both of which are involved in the pathogenesis of diabetic complications. We have shown that serum VAP-1 is higher in patients with diabetes and in patients with chronic kidney disease (CKD), and can predict cardiovascular mortality in subjects with diabetes. In this study, we investigated if serum VAP-1 can predict ESRD in diabetic subjects.

METHODS

In this prospective cohort study, a total of 604 type 2 diabetic subjects were enrolled between 1996 to 2003 at National Taiwan University Hospital, Taiwan, and were followed for a median of 12.36 years. The development of ESRD was ascertained by linking our database with the nationally comprehensive Taiwan Society Nephrology registry. Serum VAP-1 concentrations at enrollment were measured by time-resolved immunofluorometric assay.

RESULTS

Subjects with serum VAP-1 in the highest tertile had the highest incidence of ESRD (p<0.001). Every 1-SD increase in serum VAP-1 was associated with a hazard ratio of 1.55 (95%CI 1.12-2.14, p<0.01) for the risk of ESRD, adjusted for smoking, history of cardiovascular disease, body mass index, hypertension, HbA1c, duration of diabetes, total cholesterol, use of statins, ankle-brachial index, estimated GFR, and proteinuria. We developed a risk score comprising serum VAP-1, HbA1c, estimated GFR, and proteinuria, which could predict ESRD with good performance (area under the ROC curve = 0.9406, 95%CI 0.8871-0.9941, sensitivity = 77.3%, and specificity = 92.8%). We also developed an algorithm based on the stage of CKD and a risk score including serum VAP-1, which can stratify these subjects into 3 categories with an ESRD risk of 0.101%/year, 0.131%/year, and 2.427%/year, respectively.

CONCLUSIONS

In conclusion, serum VAP-1 can predict ESRD and is a useful biomarker to improve risk stratification in type 2 diabetic subjects.