Uric acid: bystander or culprit in hypertension and progressive renal disease?

The role of hyperuricemia in the progression of end-stage kidney disease and its molecular prospective in inflammation and cardiovascular diseases: A general review

With the ongoing development of the Chinese economy, the occurrence of chronic kidney disease (CKD) has experienced a remarkable upsurge recently, and due to uremia caused by CKD, the number of patients undergoing dialysis has shown a dramatic increase. China has been ranked first in the world for patients undergoing hemodialysis (HD) and peritoneal dialysis (PD) with approximately one million patients across the country. Due to the loss of kidney function caused by CKD, the kidneys tend to lose their ability to excrete uric acid (UA) out of the body; therefore, most patients undergoing dialysis are complicated with hyperuricemia (HUA). HUA is an abnormal disease of purine metabolism, and it's considered a chronic disease. More than 90% of patients suffering from HUA will not show any symptoms on physical examination. According to statistics, if high serum UA is left untreated, 55% of patients will develop severe problems due to the purine crystallization in the body, and the kidneys are the most affected organs by HUA causing renal insufficiency that can promote end-stage kidney disease (ESKD) by activating the renin-angiotensin system (RAS), which will lead to inflammation, arteriosclerosis, cardiovascular diseases (CVD), and other diseases. Lifestyle modifications and pharmacological interventions are the first primary choice for lowering UA, although dialysis will tend to reduce the high UA levels in the blood, drugs are also necessary. This review will summarize the mechanisms and metabolism of UA, the relationship between HUA and ESKD progression, HUA and inflammation, HUA and CVD, and pharmacological treatment of HUA.

Self-calibrating multiplexed microneedle electrode array for continuous mapping of subcutaneous multi-analytes in diabetes

Monitoring multiplexed biochemical markers is beneficial for the comprehensive evaluation of diabetes-associated complications. Techniques for multiplexed analyses in interstitial fluids have often been restricted by the difficulties of electrode materials in accurately detecting chemicals in complex subcutaneous spaces. In particular, the signal stability of enzyme-based sensing electrodes often inevitably decreases due to enzyme degradation or interference in vivo. In this study, we developed a self-calibrating multiplexed microneedle (MN) electrode array (SC-MMNEA) capable of continuous, real-time monitoring of multiple types of bioanalytes (glucose, cholesterol, uric acid, lactate, reactive oxygen species [ROSs], Na+, K+, Ca2+, and pH) in the subcutaneous space. Each type of analyte was detected by a discrete MN electrode assembled in an integrated array with single-MN resolution. Moreover, this device utilized an MN-delivery-mediated self-calibration technique to address the inherent problem of decreased accuracy of implantable electrodes caused by long-term tissue variation and enzyme degradation, and this technique might increase the reliability of the MN sensors. Our results indicated that SC-MMNEA could provide real-time monitoring of multiplexed analyte concentrations in a rat model with good accuracy, especially after self-calibration. SC-MMNEA has the advantages of in situ and minimally invasive monitoring of physiological states and the potential to promote wearable devices for long-term monitoring of chemical species in vivo.

Gout: global epidemiology, risk factors, comorbidities and complications: a narrative review

BACKGROUND

Gout is one of the oldest known diseases and the most common form of inflammatory arthritis. The established risk factors for gout include hyperuricemia, chronic renal disease, genetic, alcohol consumption, dietary factors, diuretic use, hypertension, obesity, and metabolic syndrome. Patients with gout have an increased risk of all-cause mortality, particularly from cardiovascular disease, cancer, and infectious diseases. Gout is also associated with several complications, such as nephrolithiasis. This literature review describes the global epidemiology and trends associated with gout, before providing an overview of its risk factors and complications.

METHODS

This research used the narrative review method. Thorough searches were performed in PubMed and Google scholar, up to June 15, 2024, for articles that evaluated the risk factors, comorbidities or complications associated with gout. Moreover, we also included studies that reported the epidemiological characteristics or burden of gout at the global, regional, or national level.

RESULTS

Gout is more prevalent in developed countries, than in developing countries, although its prevalence is increasing globally. In addition, gout is much more prevalent among males than among females. Hyperuricemia has the largest role in the development of gout, although many risk factors contribute to the increasing prevalence of gout, including genes, several medications, and diet. Gout is associated with several comorbidities and complications, which need to be taken into consideration when managing gout. In recent years, gout has been found to be associated with several new comorbidities.

CONCLUSIONS

Our findings provide a comprehensive and informative overview that can be useful for the prevention, diagnosis, and management of gout.

Managing Gout in Patients with Metabolic Syndrome

Gout is characterized by monosodium urate (MSU) crystal deposition secondary to hyperuricemia. Gout is associated with metabolic syndrome (MetS) and its related comorbid conditions such as cardiovascular disease (CVD). Major advances have been made in the comprehension of the link between MetS and gout. Despite observational studies suggesting an association between MetS-related conditions and hyperuricemia, there is no proof of causality. Most studies using Mendelian randomization did not find hyperuricemia as a causal factor for MetS-related conditions. In contrast, these conditions were found associated with hyperuricemia, which suggests a reverse causality. Among patients with gout, this high CVD risk profile implies the need for systematic screening for MetS-related conditions. Most international guidelines recommend systematic screening for and care of CVD and related risk factors in patients with gout. Some anti-hypertensive agents, such as losartan and calcium channel blockers, are able to decrease serum urate (SU) levels. However, there are potential interactions between gout management therapies and the treatment of metabolic diseases. Some data suggest that anti-inflammatory drugs used for gout flare treatment, such as colchicine or canakinumab, might have benefits for CVD. Regarding the impact of urate-lowering therapies on CVD risk, recent studies found a similar CVD safety profile for allopurinol and febuxostat. Finally, sodium-glucose cotransporter-2 inhibitors are promising for gout because of their ability to decrease SU levels and risk of recurrent flares. In this review, we focus on the clinical challenge of managing MetS in patients with gout, particularly older patients with co-medications.

Association between uric acid and referable diabetic retinopathy in patients with type 2 diabetes

Plasmatic uric acid (UA) has been inconsistently associated with diabetic retinopathy (DR). Specific sight-threatening stages of DR have not been studied for their association with UA. Cross-sectional, comparative study. Between 2014 and 2018 we recruited 210 Mexican individuals > 18 years-old with type 2 diabetes (T2D). Clinical, ophthalmological and biochemical assessment was performed with standardized funduscopic examination. Certified readers classified DR stages. The association between DR and UA was assessed by multiple logistic regression analysis, calculating odds ratios (OR) and 95% CI, after adjustment for covariates. Two hundred and ten patients were included, 41 (19.5%) had referable DR. Subjects with referable (severe or worse) DR had longer diabetes duration, 22 (15-28) vs 15 (8-20) years (P < 0.01); higher levels of UA, 6.5 (5.8-8.1) vs 5.4 (4.5-6.6) mg/dL (P < 0.01); higher systolic blood pressure, 130 (120-140) vs 120 (110-130) mmHg (P < 0.01); higher diastolic blood pressure, 78.4 ± 9.7 vs 75.4 ± 9.2 mmHg (P = 0.03); and lower glomerular filtration rate , 54.1 (41.5-69.6) vs 87.3 (66.8-108.3) mL/min/1.73m2 (P < 0.01) compared with those without referable DR. With multiple logistic regression, after adjustment, per each unit of change (mg/dL) in UA the probability of having referable DR increased 45% (OR = 1.45, 95% CI 1.12-1.87, P < 0.01). When UA was evaluated as dichotomous variable, those with levels ≥ 7.8 mg/dL had almost two times (OR = 2.81, 95% CI 1.00-7.9., P = 0.049) the probability of having referable DR compared with those with levels < 7.8 mg/dL. UA may contribute to the microvascular damage in retinal vessels and therefore hyperuricemia could be a therapeutic target to prevent DR progression.

Association of remnant cholesterol and newly diagnosed early-onset type 2 diabetes mellitus in Chinese population: A retrospective cross-sectional study

BACKGROUND

With the increasing incidence of diabetes worldwide, patients diagnosed with diabetes has been getting younger. Previous studies have shown that high remnant cholesterol (RC) level leads to an increased risk of cardiovascular disease events. However, the relationship between RC levels and newly diagnosed early-onset type 2 diabetes mellitus (T2DM) is unknown. This study aimed to explore the association between RC and newly diagnosed early-onset T2DM.

METHODS

A total of 606 patients newly diagnosed with early-onset T2DM and 619 gender-matched subjects with normal blood glucose levels were retrospectively enrolled in this study. All T2DM patients showed onset age of 18-40 years. Binary logistic regression analysis was performed to analyze independent risk factors and receiver operating characteristic (ROC) analysis was used to explore the predictive value of RC and other unconventional lipids. Moreover, the correlation between RC and insulin resistance in patients with newly diagnosed early-onset T2DM was also examined with binary logistic regression analysis and Spearman correlation analysis.

RESULTS

Increased RC level was an independent risk factor for early-onset T2DM (p < .05). The area under the curve on ROC analysis of RC was 0.805, 95% confidence interval (CI) was 0.781 ~ 0.826, sensitivity was 82.18% and specificity was 66.24%, which showed higher predictive value than those of triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and total cholesterol (TC)/HDL-C ratio. Cutoff value of RC was 0.32 mmol/L. Level of RC in early-onset T2DM patients with moderate or severe insulin resistance was significantly higher than that in patients with mild insulin resistance (p < .0001). No difference in RC levels was found between patients with moderate and severe insulin resistance (p > .05). RC was still correlated with insulin resistance after adjusting the conventional lipid parameters (TG, TC, HDL-C, and low-density lipoprotein cholesterol) using partial correlation analysis.

CONCLUSION

RC level was higher in patients with early-onset T2DM and was correlated to the degree of insulin resistance as well. Patients aged 18-40 years with RC >0.32 mmol/L showed an increased risk of developing T2DM.

Interleukin-41 as a biomarker of the anti-inflammatory response associated with hyperuricemia

BACKGROUND

Interleukin (IL)-41 is a recently discovered secreted protein that is expressed in a variety of tissues, and it is associated with several immune and metabolic diseases. However, IL-41 has not been studied in hyperuricemia (HUA).

METHODS

Forty-four HUA patients and 44 healthy controls (HCs) were included in this study, and we collected theirgeneral and biochemical parameters, including white blood cell, neutrophil, lymphocyte, and platelet counts, mean platelet volume, platelet distribution width, serum creatinine, blood urea nitrogen, fasting blood glucose, total triglyceride, total cholesterol, high-density lipoprotein, low-density lipoprotein, total protein, albumin, alkaline phosphatase, gamma-glutamyltransferase, and hemoglobin concentration. The level of serum IL-41 was determined using an enzyme-linked immunosorbent assay. Multivariate logistic regression analysis was exploited to identify the independent risk factors associated with HUA, and the clinical diagnostic value of IL-41 was analyzed by applying the receiver operating characteristic (ROC) curve. We assessed the association between IL-41 and clinical parameters with Spearman's rank correlation.

RESULTS

Circulating IL-41 levels were significantly higher in HUA patients than in the HCs group (460.3 pg/mL vs. 261.3 pg/mL, respectively; P < 0.001). The area under the ROC curve (AUC) for IL-41 in HUA patients was 0.7443 (with a cut-off value of 311.055 pg/mL, a sensitivity of 68.18 %, and a specificity of 72.73 %), while the AUC for IL-41 combined with the platelet count was 0.8109. Correlation analysis revealed that the circulating IL-41 level was positively correlated with age in HCs and HUA patients.

CONCLUSIONS

We herein demonstrated that serum IL-41 was elevated in HUA patients and that it may constitute a novel biomarker of anti-inflammatory response related to HUA.

Clinical characteristics of patients with early-onset diabetes mellitus: a single-center retrospective study

BACKGROUND

The prevalence of diabetes mellitus (DM) is dramatically increasing around the world, and patients are getting younger with changes in living standards and lifestyle. This study summarized and analyzed the clinical characteristics of different types of newly diagnosed diabetes mellitus patients with an onset age between 18 and 40 years to provide clinical evidence for the early diagnosis and treatment of diabetes, reduce short-term and long-term complications and offer scientific and personalized management strategies.

METHODS

A total of 655 patients newly diagnosed with early-onset diabetes mellitus in the Department of Endocrinology, the First Medical Center of PLA General Hospital from January 2012 to December 2022 were retrospectively enrolled in this study, with an onset age of 18-40 years. Their clinical data were collected and investigated. All patients were divided into two groups according to whether they presented with diabetic microangiopathy. Similarly, patients with early-onset type-2 diabetes were grouped in accordance with whether they had ketosis at the time of diagnosis. Binary logistic regression analysis was performed to analyze risk factors, and receiver-operating characteristic (ROC) analysis was used to explore the predictive value of significant risk factors.

RESULTS

The findings were as follows: (1) Of 655 enrolled patients, 477 (72.8%) were male and 178 (27.1%) were female, with a mean age of onset of was 29.73 years ± 0.24 SD. (2) The prevalence of early-onset diabetes was gradually increasing. Type-2 diabetes was the most common type of early-onset diabetes (491, 75.0%). The ages of onset of early-onset type-1 diabetes, type-2 diabetes and LADA were mainly 18-24 years, 25-40 years and 33-40 years, respectively. (3) Initial clinical manifestations of early-onset diabetes were classic diabetes symptoms (361, 55.1%), followed by elevated blood glucose detected through medical examination (207, 31.6%). (4) Binary logistic regression analysis suggested that high serum uric acid (UA), a high urinary albumin-to-creatinine ratio (UACR) and diabetic peripheral neuropathy (DPN) were risk factors for microangiopathy in early-onset diabetes patients (P < 0.05). The area under the curve (AUC) on ROC analysis of the combination of UA, UACR and DPN was 0.848, 95% CI was 0.818 ~ 0.875, sensitivity was 73.8% and specificity was 85.9%, which had higher predictive value than those of UA, UACR and DPN separately. (5) Weight loss, high glycosylated hemoglobin (HbA1c) and young onset age were risk factors for ketosis in patients with early-onset type-2 diabetes (P < 0.05).

CONCLUSION

(1) Men were more likely to have early-onset diabetes than women. (2) Early-onset diabetes patients with high serum uric acid levels, high UACRs and peripheral neuropathy were prone to microangiopathy. Comprehensive evaluation of these risk factors could have higher predictive value in the prediction, diagnosis and treatment of microvascular lesions. (3) Patients with weight loss at onset, high HbA1c and young onset age were more likely to develop ketosis. Attention should be given to the metabolic disorders of these patients.

Association between serum uric acid levels and cardiovascular risk factors among adults in India

BACKGROUND AND AIM

The objective of this study was to explore the association between serum uric acid (SUA) levels and cardiovascular risk factors in the Indian population.

METHODS AND RESULTS

This was a cross-sectional, population-based study. The study enrolled adults aged 20 years and above residing in rural, sub-urban, and urban. All participants completed a detailed questionnaire, underwent anthropometric measurements, and had blood samples collected. Participants were divided into three tertiles based on their SUA concentrations. A total of 2976 participants were included in this study, with 865 from rural, 1030 from sub-urban, and 1081 from urban populations. The mean values of cardiovascular risk factors were significantly higher in tertile 3 (p < 0.001) as compared to the other tertiles. However, we observed a negative trend between the increase of SUA and SUA/Scr ratio and HbA1c levels (Pearson correlation r = -0.068; p < 0.001 and r = -0.140; p < 0.001, respectively). The healthy and prediabetic groups did not show any significant change in HbA1c with increasing SUA levels, while an inverse trend was observed in diabetics. In the diabetic population, both men and women showed an inverse trend between increasing SUA levels and HbA1c in both known and newly diagnosed diabetes (p < 0.001).

CONCLUSIONS

The study found a positive association between SUA levels and cardiovascular risk factors. However, HbA1c was inversely correlated with increasing SUA tertiles in both known and newly diagnosed diabetes, as compared to the general population. Additionally, both men and women with diabetes consistently showed an inverse relationship between increasing SUA/SCr ratio and HbA1c levels.

Influence of Serum Uric Acid on Macular Choroidal Thickness and Ganglion Cell Inner Plexiform Layer Thickness

Purpose

The purpose of this study was to determine the influence of serum uric acid (UA) on macular choroidal and ganglion cell inner plexiform layer (GC-IPL) thickness.

Methods

This cross-sectional study enrolled adult individuals in communities in Guangzhou, China. All participants underwent a comprehensive ophthalmologic examination. They were divided into four groups according to UA quartiles. The choroidal and GC-IPL thickness was measured by swept-source optical coherence tomography (SS-OCT).

Results

A total of 719 subjects (1389 eyes) were included in the study. The average UA was 348.50 ± 86.16 mmol/L. The average choroidal and GC-IPL thickness decreased with UA quartiles (P < 0.001). Multivariate linear regression analyses showed that UA was negatively associated with average choroidal (β = -0.073, 95% confidence interval [CI] = -0.117 to -0.028, P = 0.001) and GC-IPL thickness (β = -0.006, 95% CI = -0.009 to -0.002, P = 0.001). After adjusting for confounding factors, the average choroidal thickness was decreased in quartile 4 as compared with quartile 1 by -14.737 µm (95% CI = -24.460 to -5.015, P = 0.003). The average GC-IPL thickness was decreased in quartile 4 versus quartile 1 by -1.028 (95% CI = -1.873 to -0.290, P = 0.007).

Conclusions

Higher UA levels were independently associated with macular choroid and GC-IPL thinning. These contribute to a better understanding of ocular pathological mechanisms.

Translational Relevance

The associated UA with choroidal and GC-IPL thickness helps to understand the ocular pathological and retinal neurodegenerative mechanism.

Uric acid and gamma-glutamyl-transferase in children and adolescents with obesity: Association to anthropometric measures and cardiometabolic risk markers depending on pubertal stage, sex, degree of weight loss and type of patient care: Evaluation of the adiposity patient follow-up registry

OBJECTIVES

Associations between body mass index (BMI)- standard deviation score (SDS)/waist-to-height ratio (WHtR) were studied with (i) serum uric acid (sUA)/gamma-glutamyl-transferase (GGT) and (ii) cardiometabolic risk markers in children with obesity, considering sex, pubertal development, and degree of weight loss/type of patient care.

METHODS

102 936 children from the Adiposity-Follow-up registry (APV; 47% boys) were included. Associations were analysed between sUA/GGT and anthropometrics, transaminases, lipids, fasting insulin (FI), homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides to HDL-cholesterol (TG/HDL)-ratio. Follow-up analyses (3-24 months after baseline) considered a BMI-SDS reduction ≥0.2 (n = 11 096) or ≥0.5 (n = 3728). Partialized correlation analyses for sex and BMI-SDS were performed, taking pubertal development into consideration.

RESULTS

At baseline, BMI-SDS showed the strongest correlations to sUA (r = 0.35; n = 26 529), HOMA-IR/FI (r = 0.30; n = 5513 /n = 5880), TG/HDL-ratio (r = 0.23; n = 24 501), and WHtR to sUA (r = 0.32; n = 10 805), GGT (r = 0.34; n = 11 862) and Alanine-aminotransferase (ALAT) (r = 0.33; n = 11 821), with stronger correlations in boys (WHtR and GGT: r = 0.36, n = 5793) and prepubertal children (r = 0.36; n = 2216). GGT and sUA (after partializing effects of age, sex, BMI-SDS) showed a correlation to TG/HDL-ratio (r = 0.27; n = 24 501). Following a BMI-SDS reduction ≥0.2 or ≥0.5, GGT was most strongly related to Aspartate-aminotransferase (ASAT)/ ALAT, most evident in prepuberty and with increasing weight loss, and also to TG/HDL-ratio (r = 0.22; n = 1528). Prepubertal children showed strongest correlations between BMI-SDS/WHtR and GGT. ΔBMI-SDS was strongly correlated to ΔsUA (r = 0.30; n = 4160) and ΔGGT (r = 0.28; n = 3562), and ΔWHtR to ΔGGT (r = 0.28; n = 3562) (all p < 0.0001).

CONCLUSION

Abdominal obesity may trigger hyperuricemia and hepatic involvement already in prepuberty. This may be stronger in infancy than anticipated to date. Even moderate weight loss has favourable effects on cardiometabolic risk profile and glucose homeostasis.

Urate Transporter 1 Can Be a Therapeutic Target Molecule for Chronic Kidney Disease and Diabetic Kidney Disease: A Retrospective Longitudinal Study

Chronic kidney disease (CKD) is a major global health problem for which there are no curative drug treatments. Hyperuricemia is one of risk factors for CKD. The evidence on effects of uric acid (UA)-lowering treatments on the progression of CKD was very limited and previous meta-analyses used only trials which primarily used xanthin oxidase (XO) inhibitors because the reports on fulminant hepatitis due to benzbromarone kept us from using uricosuric agents for hyperuricemia patients. Dotinurad, a novel selective urate reabsorption inhibitor for the treatment of hyperuricemia, reduces serum UA levels by selectively inhibiting urate transporter 1 (URAT1). We retrospectively picked up patients who had taken dotinurad from June 2018 to August 2021 and compared metabolic parameters at baseline with the data at 3 and 6 months after the start of dotinurad. We found 84 patients, and approximately 74% of patients were complicated with CKD. After the start of dotinurad, improvements in serum lipids, systolic blood pressure, body weight, and albuminuria, in addition to reduction in serum UA, were observed. Dotinurad increased urinary UA excretion, and was effective to reduce serum UA in patients with both UA underexcretion type and renal UA overload type. Furthermore, urinary UA excretion was significantly and negatively correlated with serum creatine levels at baseline and at 6 months after the start of dotinurad, and the change in urinary UA excretion after 3 months was significantly and negatively correlated with change in serum creatine levels. The property of dotinurad, which selectively inhibits URAT1, but not other UA transporters, such as ATP-binding cassette, subfamily G, and 2 (ABCG2), which ABCG2 is a UA and uremic toxin exporter, may be beneficially associated with pathology of CKD. URAT1 can be a therapeutic target molecule for CKD and DKD.

Association of WBC Counts, Leukocyte Ratios, and Serum Uric Acid with Clinical Outcome of Intravitreal Bevacizumab in Diabetic Macular Edema

Purpose

To investigate the role of serum uric acid and leukocyte counts and ratios as predictors of clinical outcomes of intravitreal bevacizumab in diabetic macular edema.

Method

In this prospective study, the patients were treated with three monthly intravitreal bevacizumab. The correlation of serum uric acid and immune cell indices with the changes of best corrected visual acuity and central macular thickness at the end of month 3 were evaluated through univariate and multivariate linear regression analysis.

Result

A total of 80 eyes from 80 diabetic patients were included in the study. The difference of uric acid level and immune indices between groups with different retinopathy severity was no statistically significant(P>0.05). Lower duration of diabetes (P=0.0451), monocyte count (P=0.021), and uric acid level (P<0.001) were correlated with larger improvement in visual acuity at 3-month visit. Higher logMAR of baseline visual acuity (P=0.007), lymphocyte count (P=0.008), lymphocyte-to-neutrophil ratio (LNR) (P<0.001) and lymphocyte-to-platelet ratio (LPR) (P<0.001) were correlated with larger improvement in visual acuity at 3-month visits. According to multivariate analysis, baseline logMAR (coefficient=0.125, P=0.009), duration of diabetes (coefficient=-0.216, P=0.047), LNR (coefficient=0.712, P<0.001), LPR (coefficient=0.238, P<0.001), and uric acid level (coefficient=-0.397, P<0.001) were the significant predictors of changes in visual acuity in our subset of patients.

Conclusion

Serum uric acid and leukocyte counts and ratios may predict the response of diabetic macular edema to intravitreal injection.

Excess comorbidities in gout: the causal paradigm and pleiotropic approaches to care

Gout is a common hyperuricaemic metabolic condition that leads to painful inflammatory arthritis and a high comorbidity burden, especially cardiometabolic-renal (CMR) conditions, including hypertension, myocardial infarction, stroke, obesity, hyperlipidaemia, type 2 diabetes mellitus and chronic kidney disease. Substantial advances have been made in our understanding of the excess CMR burden in gout, ranging from pathogenesis underlying excess CMR comorbidities, inferring causal relationships from Mendelian randomization studies, and potentially discovering urate crystals in coronary arteries using advanced imaging, to clinical trials and observational studies. Despite many studies finding an independent association between blood urate levels and risk of incident CMR events, Mendelian randomization studies have largely found that serum urate is not causal for CMR end points or intermediate risk factors or outcomes (such as kidney function, adiposity, metabolic syndrome, glycaemic traits or blood lipid concentrations). Although limited, randomized controlled trials to date in adults without gout support this conclusion. If imaging studies suggesting that monosodium urate crystals are deposited in coronary plaques in patients with gout are confirmed, it is possible that these crystals might have a role in the inflammatory pathogenesis of increased cardiovascular risk in patients with gout; removing monosodium urate crystals or blocking the inflammatory pathway could reduce this excess risk. Accordingly, data for CMR outcomes with these urate-lowering or anti-inflammatory therapies in patients with gout are needed. In the meantime, highly pleiotropic CMR and urate-lowering benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors and key lifestyle measures could play an important role in comorbidity care, in conjunction with effective gout care based on target serum urate concentrations according to the latest guidelines.

Association between uric acid level and incidence of albuminuria in patients with type 2 diabetes mellitus: A 4.5-year cohort study

Using animal models and molecular biology researches, hyperuricemia has been shown to instruct renal arteriolopathy, arterial hypertension, and microvascular injury involving the renin-angiotensin system and resulting in renal function impairment. Nevertheless, the association between uric acid levels and the development of albuminuria has been under-investigated in patients with type 2 diabetes mellitus. Patients with type 2 diabetes and regular outpatient visits were recruited from the Puli Branch of the Taichung Veterans General Hospital in Taiwan since January 2014. Demographics, lifestyle features, and medical history were gathered by well-trained interviewers. All participants underwent comprehensive physical examinations, including a biochemical assay of venous blood specimens and urine samples after an 8-hour overnight fast. Participants were followed until June 2018. The primary outcome was the albuminuria incidence. Univariable and multivariable Cox regression analysis were employed to explore the relation between uric acid and incident albuminuria. Uric acid cutoffs for incident albuminuria were determined with the receiver operator characteristic curve. We included 247 qualified subjects (mean age: 64.78 years old [standard deviation = 11.29 years]; 138 [55.87%] men). During a 4.5-year follow-up duration, 20 subjects with incident albuminuria were recognized. Serum uric acid was significantly associated with an increased risk of incident albuminuria (adjusted hazard ratio = 2.39; 95% confidence interval: 1.53-3.75; P < .001) with potential confounders adjustment. The uric acid cutoff point was 6.9 mg/dL (area under the curve 0.708, sensitivity 60.0%, specificity 84.58%) for incident albuminuria. Serum uric acid was associated with incident albuminuria among patients with type 2 diabetes.

Molecular Biological and Clinical Understanding of the Pathophysiology and Treatments of Hyperuricemia and Its Association with Metabolic Syndrome, Cardiovascular Diseases and Chronic Kidney Disease

Uric acid (UA) is synthesized mainly in the liver, intestines, and vascular endothelium as the end product of an exogenous purine from food and endogenously from damaged, dying, and dead cells. The kidney plays a dominant role in UA excretion, and the kidney excretes approximately 70% of daily produced UA; the remaining 30% of UA is excreted from the intestine. When UA production exceeds UA excretion, hyperuricemia occurs. Hyperuricemia is significantly associated with the development and severity of the metabolic syndrome. The increased urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) expression, and glycolytic disturbances due to insulin resistance may be associated with the development of hyperuricemia in metabolic syndrome. Hyperuricemia was previously thought to be simply the cause of gout and gouty arthritis. Further, the hyperuricemia observed in patients with renal diseases was considered to be caused by UA underexcretion due to renal failure, and was not considered as an aggressive treatment target. The evidences obtained by basic science suggests a pathogenic role of hyperuricemia in the development of chronic kidney disease (CKD) and cardiovascular diseases (CVD), by inducing inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and activation of the renin-angiotensin system. Further, clinical evidences suggest that hyperuricemia is associated with the development of CVD and CKD. Further, accumulated data suggested that the UA-lowering treatments slower the progression of such diseases.

Hyperuricemia and Its Associated Factors Among Adult Staff Members of the Ethiopian Public Health Institute, Ethiopia

Background

Hyperuricemia is related not only to an increased risk of gouty arthritis but also to an increased risk of cardiovascular diseases, resistant hypertension, insulin resistance and progression of type 2 diabetes mellitus. However, to the best of our knowledge, the prevalence of hyperuricemia and its associated factors have rarely been assessed in Ethiopian populations. Therefore, this study aimed to determine the prevalence of hyperuricemia and its associated factors among adult staff members of the Ethiopian Public Health Institute.

Methods

An institution-based cross-sectional study was conducted from July 1 to October 28, 2018. A total of 402 study participants were selected using a simple random sampling technique. An interviewer-administered questionnaire was used to collect the data. A blood sample of approximately 5 mL was collected from each study participant after overnight fasting through standardized methods for biochemical tests, and analyses were carried out with an automated COBAS 6000 analyzer. Data analysis was performed by SPSS version 20 software. The factors associated with the outcome variable were identified by bivariable and multivariable logistic regression analyses, and a p value <0.05 was used to declare statistical significance.

Results

The mean age of the study participants was 37.13±10.5 (mean ± SD), and 51.5% of the participants were male. The overall prevalence of hyperuricemia (>5.7 mg/dL for females and >7 mg/dL for males) was found to be 31.0%. The multivariable logistic analysis revealed that age (AOR=1.59, 95% CI 1.01–2.78), sex (AOR=1.66, 95% CI 1.02–2.70), cigarette smoking (AOR=2.05, 95% CI 1.01–4.19) and serum low-density lipoprotein (LDL) (AOR=1.70, 95% CI 1.01–2.87) were significantly associated with hyperuricemia.

Conclusion

The prevalence of hyperuricemia was relatively high compared to similar studies. Early screening for hyperuricemia in the general population, especially in those who are smokers, of older age and with high serum LDL levels, is vital to control its adverse effects at an early stage.

Age and sex dependent association of uric acid and incident hypertension

BACKGROUND AND AIMS

A previous meta-analysis suggested that the relationship between hyperuricemia and hypertension may be stronger in younger individuals and women. We aimed to investigate the age and sex dependent association of uric acid (UA) and incident hypertension.

METHODS AND RESULTS

We analyzed data from the Health Examinees Study, a community-based prospective cohort study conducted in Korea from 2004 to 2013. It included 29,088 non-hypertensive subjects aged 40-79 (age, 52.5 ± 7.8 years; men, 31.4%) who had serum UA measurement and participated in the follow-up survey. The risk factors of hypertension were assessed using Cox regression. Over a mean 3.8 years of follow-up, 1388 men (15.2%) and 1942 women (9.7%) were newly diagnosed with hypertension. Upon age- and sex-based stratification, the risk of hypertension was highest in hyperuricemic subjects aged 40-49 years (HR: women, 2.16; men, 1.30). Across the entire cohort, the risk of incident hypertension was higher in groups with higher serum UA levels, and highest in women aged 40-49 years (HR, 1.44; P < 0.001). On multivariable linear regression analysis, the higher the baseline serum UA level, the greater the increase in blood pressure during follow-up, and this effect was strongest in women aged 40-49 years (β = 0.87 and P < 0.01 for systolic blood pressure).

CONCLUSIONS

The relationship between uric acid and incident hypertension tended to be dependent on age and sex. Younger women are at highest risk of UA-related incident hypertension.

14-Day Repeated Intraperitoneal Toxicity Test of Ivermectin Microemulsion Injection in Wistar Rats

To evaluate the safety of ivermectin microemulsion injection, 100 Wistar rats were injected intraperitoneally at 0.38 g/kg, 0.19 g/kg, and 0.1 g/kg for 14 days. The 14-day repeated toxicity test of ivermectin microemulsion injection was systematically evaluated by clinical observation, organ coefficient, hematological examination, clinical chemistry examination, and histopathological examination. The results showed that no rats died during the test. At the initial stage of treatment, the rats in the high dose group had mild clinical reaction, which disappeared after 4 days. Clinical chemistry showed that the high dose of ivermectin microemulsion could cause significant changes in ALT and LDH parameters in male rats; high and medium doses could increase the liver coefficients of male and female rats. The toxic target organ may be the liver as indicated by histopathological findings. No significant toxic injury was found in the heart, liver, spleen, lung, kidney, brain, ovary, and testes of all groups of rats. No drug-related toxic effects were found at low doses, and thus the NOVEL of ivermectin microemulsion injection was 0.19 g/kg.

Estimate of prevalent hyperuricemia by systemic inflammation response index: results from a rural Chinese population

OBJECTIVES

Hyperuricemia is a common metabolic disease that is intimately correlated with inflammation. Our study aimed to investigate the value of systemic inflammation response index as a novel inflammatory marker to estimate hyperuricemia in the rural Chinese population.

METHODS

This cross-sectional study used the data of 8,095 Chinese men and women aged ≥35 years from the 2012-2013 Northeast China Rural Cardiovascular Health Study.

RESULTS

The overall prevalence of hyperuricemia was 12.84%. After fully adjusting for potential confounders, each SD increase of SIRI in men and women caused a 21.4% and 37.0% additional risk, respectively, for hyperuricemia. Moreover, smooth curve fitting and subgroup analyses corroborated the linearity and robustness of this correlation. ROC analysis showed the ability of SIRI to estimate hyperuricemia was significantly improved in females (0.741 vs 0.745, P = 0.043), but not in males (0.710 vs 0.714, P = 0.105). The net reclassification improvement (NRI, 0.120 in men vs 0.166 in women) and integrated discrimination improvement (IDI, 0.002 in men vs 0.006 in women) showed a significant improvement for both genders.

CONCLUSIONS

Our present study suggests a linear and robust relationship between SIRI and prevalent hyperuricemia, which implicates the value of SIRI to optimize the risk stratification and prevention of hyperuricemia.

Association between pre-and postnatal growth and longitudinal trends in serum uric acid levels and blood pressure in children aged 3 to 7 years

Background

Uric acid has been identified as an important factor in the development of hypertension. If low birth weight (LBW) combined with catch-up growth (CUG) is associated with continuously elevated serum uric acid levels (SUA) level trajectories, LBW children who experience CUG may have an increased risk of hypertension later in life. Therefore, this cohort study analyzed longitudinal trends in SUA levels and changes in blood pressure in relation to pre- and postnatal growth over an extended follow-up period.

Methods

This prospective cohort study of 364 children from the Ewha Birth and Growth Cohort assessed the effects of pre- and postnatal growth status on SUA at 3, 5, and 7 years of age using a linear mixed model and the change in blood pressure over the 7-year follow-up period using a generalized linear model (analysis of covariance). CUG was defined as a change in weight (between birth and age 3) with a z-score > 0.67 for LBW subjects. The multivariate model considered sex, gestational age, and uric acid, height, and weight at 3 years of age.

Results

Children with LBW and CUG had higher SUA for the first 7 years of life compared to the normal birth weight group. This trend was particularly evident when comparing LBW children at term to children with normal birth weight. Within the group with LBW at term, children with greater CUG had higher SUA than children with normal birth weight, and this difference increased with age. Changes in the systolic blood pressure between 3 and 7 years of age were higher by 7.9 mmHg in children who experienced LBW and CUG compared with those who had a normal birth weight after adjusting for sex, gestational age, and height, weight, and uric acid at 3 years of age (p-value = 0.08).

Conclusions

The uric acid levels and changes in systolic blood pressure were consistently higher among LBW children who experienced CUG compared with NBW children for the first 7 years of life. LBW children who experienced greater weight gain from birth to age 3 had even higher uric acid levels compared with NBW children.

Impact of Alpha-Lipoic Acid Chronic Discontinuous Treatment in Cardiometabolic Disorders and Oxidative Stress Induced by Fructose Intake in Rats

Insulin resistance (IR) and cardiometabolic disorders are the main consequences of today’s alimentary behavior. This study evaluates the effects of a chronic-discontinuous treatment with alpha-lipoic acid (AL), an antioxidant substance that improves glycemic control associated with diabetes mellitus, on metabolic disorders and plasma oxidative stress induced by fructose intake, in rats. Sprague-Dawley rats (48 animals) were randomized into two series (n = 24): rats fed with standard chow or with standard chow supplemented with 60% fructose. In each of the two series, for 2 weeks/month over 12 weeks, a group of rats (n = 12) was intraperitoneally injected with NaCl 0.9%, and a second group (n = 12) received AL 50 mg/kg/day. Body weight, glycemia, and systolic blood pressure were monitored throughout the study. After 12 weeks, IR, plasma lipoproteins, uric acid, transaminase activities, and oxidative stress markers were assessed. The high fructose-enriched diet induced cardiometabolic disorders (hypertension, hyperglycemia, IR and dyslipidemia), an increase in uric acid concentration, transaminase activities and C-reactive protein level. This diet also enhanced plasma products of lipid and protein oxidation, homocysteine level, and decreased GSH/GSSG ratio. In this field, there is evidence to indicate that oxidative stress plays an important role in the etiology of diabetic complications. AL discontinuous treatment prevents the metabolic disorders induced by fructose intake, reduced plasma lipid and protein oxidation-products, and restored the GHS/GSSG ratio. Our study proves a promising potential of the chronic-discontinuous treatment of AL and highlights the pleiotropic effects of this antioxidant substance in metabolic disorders such as diabetes.

The relationship of blood pressure with uric acid and bilirubin in young lean and overweight/obese men and women: the African-PREDICT study

Mounting evidence supports the central role of oxidative stress and inflammation in obesity and the development of hypertension. However, most studies focusing on the non-enzymatic antioxidants, such as uric acid and bilirubin, and their relationship with obesity and hypertension were done in older populations with overt cardiovascular disease. The aim of this study was therefore to compare measures of cardiovascular function (blood pressure and arterial stiffness) and non-enzymatic antioxidants (uric acid and bilirubin) between young healthy lean and overweight/obese men and women and to investigate the link between these variables. We grouped 967 men and women (aged 20-30 years) according to body mass index (BMI) categories (lean BMI < 25 kg/m²; overweight/obese BMI ≥ 25 kg/m²). Cardiovascular measurements included 24 h blood pressure and carotid-femoral pulse wave velocity. Serum samples were used to analyse uric acid and bilirubin. Women and men with a BMI ≥ 25 kg/m² displayed higher 24 h blood pressure (P < 0.001) and uric acid (P ≤ 0.014) than their lean counterparts; lean women showed higher bilirubin (P < 0.001). In multi-variable adjusted regression analyses we found that 24 h systolic blood pressure was independently associated with uric acid (R² = 0.10; β = 0.19; P = 0.017) only in overweight/obese women. In lean women a negative association of 24 h systolic blood pressure with bilirubin (R² = 0.03; β = -0.14; P = 0.018) was found. No associations were found in men. In conclusion, we found adverse associations between blood pressure and uric acid in young healthy women with increased adiposity, but not in lean women or men.

New Rice-Derived Short Peptide Potently Alleviated Hyperuricemia Induced by Potassium Oxonate in Rats

Gout that caused by hyperuricemia affects human health seriously and more efficient drugs are urgently required clinically. In this study, a novel peptide named RDP1 (AAAAGAKAR, 785.91 Da) was identified from the extract of shelled fruits of Oryza sativa. Our results demonstrated that RDP1 (the minimum effective concentration is 10 μg/kg) could significantly reduce the serum uric acid and creatinine and alleviate hyperuricemic nephropathy in rats by intragastric administration. RDP1 inhibited xanthine oxidase, which also was verified at the animal level. Results from molecular docking indicated that RDP1 can inhibit uric acid formation by occupying the binding site of xanthine oxidase to xanthine. Besides, RDP1 showed no toxicity on rats and was stable in several temperatures, demonstrating its advantages for transportation. This research was the first discovery of antihyperuricemic peptide from the shelled fruits of O. Sativa and provided a new candidate for the development of hypouricemic drugs.

Relationship between oxidative stress and inflammation in hyperuricemia: Analysis based on asymptomatic young patients with primary hyperuricemia

The average age of hyperuricemia patients has gradually decreased, but young patients with primary hyperuricemia often do not exhibit clinical symptoms and have not received sufficient attention. However, a lack of symptoms with primary hyperuricemia does not mean that high serum uric acid (UA) levels cannot lead to pathological effects, such as oxidative stress and inflammation, and the specific damage is still unclear. We aimed to determine the relationship between oxidative stress and inflammation to explore the possible role of pathological damage in asymptomatic young patients with primary hyperuricemia.A total of 333 participants were enrolled in our study: 158 asymptomatic young patients with primary hyperuricemia and 175 healthy persons from a health check-up population. Malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and general biochemical markers were measured.We found no differences in biochemical markers (fasting glucose, TG, TC, LDL-C, HDL-C, SCr, BUN, AST, and ALT) between the patients and healthy persons. Subsequent analyses of oxidative stress and inflammation revealed that the serum levels of MDA, IL-6, and TNF-α in the patients were significantly higher than those in the healthy control group (P < .001), and the SOD activity was significantly lower (P < .001). As the UA levels increased, MDA increased significantly and SOD decreased significantly; likewise, IL-6 and TNF-α increased significantly as the UA level increased. MDA showed a significant positive correlation with IL-6 (r = 0.367, P < .001) and TNF-α (r = 0.319, P < .001), and SOD was negatively correlated with IL-6 (r = -0.241, P < .01) and TNF-α (r = -0.308, P < .001). Multivariable logistic regression analysis showed that UA (OR: 2.379, 95% CI: 1.698-3.286, P < .001; OR: 3.261, 95% CI: 1.729-3.857, P < .001; for IL-6 and TNF-α, respectively) and MDA (OR: 1.836, 95% CI: 1.283-2.517, P < .01; OR: 2.532, 95% CI: 1.693-3.102, P < .001; for IL-6 and TNF-α, respectively) were risk factors for high IL-6 and TNF-α and that SOD (OR: 0.517, 95% CI: 0.428-0.763, P < .01; OR: 0.603, 95% CI: 0.415-0.699, P < .001; for IL-6 and TNF-α, respectively) was a protective factor.In our study, some abnormal pathological effects were found in asymptomatic young patients with hyperuricemia, suggesting that in young hyperuricemia patients, oxidative stress, inflammation and the inflammatory response may be related to the oxidative stress induced by UA. Therefore, we should pay more attention to the pathological damage caused by these alterations.

Interactive effect of serum uric acid and total bilirubin for micro-vascular disease of type 2 diabetes in China

AIMS

Serum uric acid (SUA) and bilirubin at high levels had both pro-oxidant and anti-oxidant properties. The present study aimed to examine additive interactions between SUA and total bilirubin (TBIL) for the risk of micro-vascular disease (MVD) in type 2 diabetes mellitus (T2DM).

METHODS

A cross-sectional survey of 6713 inpatients with T2DM was conducted in 81 tertiary care hospitals in China. MVD was defined as having either prior diabetic retinopathy (DR) or diabetic nephropathy (DN). Binary logistic regression was used to estimate odds ratios of SUA and TBIL for MVD. Additive interaction was measured by three indices, i.e., relative excess risk due to interaction, attributable proportion due to interaction and synergy index.

RESULTS

Among 6713 inpatients, 408 (6.08%) suffered from MVD. SUA ≥ 283 μmol/l (i.e., its media) was defined as high SUA, and TBIL <11.5 μmol/l (n = 2290 or 34.11%) was defined as low TBIL. Overall, 621 patients were exposed to co-presence of high SUA and low TBIL. The co-presence of both factors greatly increased the effect sizes from 1.03(95%CI: 0.72-1.46) (high SUA alone) or 0.70(95%CI: 0.48-1.05) (low TBIL alone) to 1.90 (95%CI: 1.26-2.87) for MVD in multivariable analysis. The additive interaction of both factors was significant for MVD in both univariable analysis and multivariable analysis.

CONCLUSIONS

Co-presence of both high SUA and low TBIL indentified a group of patients at a markedly increased risk of MVD in high-risk Chinese patients with T2DM.

Impact of hyperuricemia on clinical outcomes after percutaneous coronary intervention for in-stent restenosis

Background

There have been limited data on the impact of hyperuricemia on long-term clinical outcomes after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR).

Methods

From January 2009 to July 2015, 317 patients who underwent repeat PCI for ISR were divided into two groups: patients with normal serum uric acid (UA) levels (normal UA group) and patients with higher serum UA levels (higher UA group). The higher UA group included patients with serum UA levels > 6.8 mg/dL or patients who were taking anti-hyperuricemic medication.

Results

During a median follow-up period of 1088 days, the cumulative incidence rates of major adverse event (MAE), including a composite of all-cause death, non-fatal myocardial infarction, and any revascularization, were similar between the two groups (higher UA 36.4% vs. normal UA 29.9%, p = 0.389, log-rank p = 0.367). Follow-up angiographic data showed similar outcomes of late lumen loss (0.8 ± 0.9 mm vs. 0.8 ± 1.1 mm, p = 0.895) and binary restenosis rate (28.1% vs. 34.7%, p = 0.622). Multivariate Cox regression analysis indicated higher levels of low-density lipoprotein cholesterol (hazard ratio [HR] 1.011, 95% confidence interval [CI] 1.003–1.019, p = 0.006) and lower left ventricular ejection fraction (HR 0.972, 95% CI 0.948–0.996, p = 0.022), but not UA levels, to be the independent risk predictors of MAE.

Conclusion

Hyperuricemia is not associated with poor clinical outcomes after repeat PCI for ISR lesions.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0840-2) contains supplementary material, which is available to authorized users.

Serum uric acid and renal function in patients with type 1 diabetes: a nationwide study in Brazil

BACKGROUND

Diabetes nephropathy is a microvascular complication associated with high morbidity and mortality in patients with type 1 diabetes, and its pathogenesis is not fully understood. Our aim was to evaluate the association between levels of serum uric acid and renal function assessed by glomerular filtration rate (GFR) and albuminuria in patients with type 1 diabetes.

METHODS

This is a multicenter, cross-sectional, observational study with 1686 patients, conducted between August 2011 and August 2014 in 14 public clinics from ten Brazilian cities. Renal function was estimated by CKD-EPI (adults) and by Schwartz (adolescents).

RESULTS

We analyzed 1686 patients, aged 30.1 ± 12.0, with 15.4 ± 9.3 years of duration of diabetes; 55.8% were female and 54.0% were Caucasians. Serum uric acid was related to renal function, with a mean of 4.8 ± 1.4 (in the normal renal function group) vs 5.2 ± 2.0 (GFR ≥ 60 ml/min and albuminuria) vs 6.5 ± 2.6 mg/dl (GFR < 60 ml/min). In the pooled group, multivariate analysis showed an inverse correlation between serum uric acid and GFR (r = - 0.316, p < 0.001) with a decrease of 4.11 ml/min in the GFR for every increase of 1 mg/dl in serum uric acid. Considering only patients with normal renal function (n = 1170), a decrease of 2.04 ml/min in the GFR for every increase of 1 mg/dl in Serum uric acid was noted using multivariate analysis.

CONCLUSIONS

Patients with higher levels of serum uric acid have worse renal function, independently of HbA1c or duration of diabetes, which persisted even in patients with normal renal function. Further prospective studies are necessary to establish if patients with higher serum uric acid may have an elevated risk for developing chronic kidney disease.

Uric acid causes kidney injury through inducing fibroblast expansion, Endothelin-1 expression, and inflammation

Background

Uric acid (UA) plays important roles in inducing renal inflammation, intra-renal vasoconstriction and renal damage. Endothelin-1 (ET-1) is a well-known profibrotic factor in the kidney and is associated with fibroblast expansion. We examined the role of hyperuricemia conditions in causing elevation of ET-1 expression and kidney injury.

Methods

Hyperuricemia was induced in mice using daily intraperitoneal injection of uric acid 125 mg/Kg body weight. An NaCl injection was used in control mice. Mice were euthanized on days-7 (UA7) and 14 (UA14). We also added allopurinol groups (UAL7 and UAL14) with supplementation of allopurinol 50 mg/Kg body weight orally. Uric acid and creatinine serum were measured from blood serum. Periodic Acid Schiff (PAS) and Sirius Red staining were done for glomerulosclerosis, tubular injury and fibrosis quantification. mRNA expression examination was performed for nephrin, podocin, preproEndothelin-1 (ppET-1), MCP-1 and ICAM-1. PDGFRβ immunostaining was done for quantification of fibroblast, while α-SMA immunostaining was done for localizing myofibroblast. Western blot analysis was conducted to quantify TGF-β1, α-SMA and Endothelin A Receptor (ETAR) protein expression.

Results

Uric acid and creatinine levels were elevated after 7 and 14 days and followed by significant increase of glomerulosclerosis and tubular injury score in the uric acid group (p < 0.05 vs. control). Both UA7 and UA14 groups had higher fibrosis, tubular injury and glomerulosclerosis with significant increase of fibroblast cell number compared with control. RT-PCR revealed down-regulation of nephrin and podocin expression (p < 0.05 vs. control), and up-regulation of MCP-1, ET-1 and ICAM-1 expression (p < 0.05 vs. control). Western blot revealed higher expression of TGF-β1 and α-SMA protein expression. Determination of allopurinol attenuated kidney injury was based on reduction of fibroblast cell number, inflammation mediators and ppET-1 expression with reduction of TGF-β1 and α-SMA protein expression.

Conclusions

UA induced glomerulosclerosis, tubular injury and renal fibrosis with reduction of podocyte function and inflammatory mediator elevation. ET-1 and fibroblast expansion might modulate hyperuricemia induced renal fibrosis.

Serum Uric Acid and Its Association with Longitudinal Cognitive Change Among Urban Adults

Uric acid, a waste metabolite among humans, was linked to various cognitive outcomes. We describe sex and age-group specific associations of baseline serum uric acid (SUAbase) and significant change in SUA (ΔSUA: 1 versus 0 = decrease versus no change; 2 versus 0 = increase versus no change) with longitudinal annual rate of cognitive change among a large sample of urban adults. Data from the Healthy Aging in Neighborhoods of Diversity across the Life Span study, 2004-2009 (visit 1) and 2009-2013 (visit 2) were used. Of 3,720 adults selected at baseline (age range: 30-64 y), complete data were available for N = 1,487-1,602 with a mean repeat of 1.5-1.7 visits/participant. Cognitive test domains spanned attention, processing speed, learning/memory, executive function, visuo-spatial/visuo-construction ability, language/verbal, and global cognitive function. SUA was measured at both visits. Multiple mixed-effects regression analyses were conducted. In the total population, a higher SUAbase was associated with a faster annual rate of decline on a measure of visual memory/visuo-construction ability (the Benton Visual Retention Test) by γ= 0.07 with a standard error of 0.02, p < 0.001. Among older men, a significant increase in SUA was associated with slower decline on a test of attention/processing speed, namely Trailmaking test, Part A, measured in seconds to completion (γ= -6.91 ± 1.73, p < 0.001). In sum, a higher SUAbase was associated with faster cognitive decline over-time in a visual memory/visuo-construction ability test. ΔSUA had particular beneficial effects of an increasing ΔSUA on the domain of attention/processing speed among older men. More longitudinal studies are needed to examine cognitive domain-specific effects of over-time change in SUA within sex and age groups.

Association between serum uric acid level and hypertension in a Chinese elderly rural population

Previous studies have examined the association between elevated serum uric acid (SUA) level and hypertension; however, the association in the Chinese elderly is still uncertain. A cross-sectional study was performed in a rural district of Beijing. A total of 2,397 participants (967 men and 1,430 women) completed the survey. The SUA levels of participants were categorized into four levels using the quartiles (P25, P50, and P75) as cutoff values. Participant was diagnosed as hyperuricemia if the SUA level was ≥417 μmol/L (male) or ≥357 μmol/L (female). Hypertension was defined as systolic blood pressure (BP) ≥140 mmHg and/or diastolic BP ≥90 mmHg and/or receiving antihypertensive drug treatment. Multiple logistic regression was used to estimate the association between SUA and hypertension. We found that higher SUA level was associated with the increased risk of hypertension in both sexes, even after adjusting for potential confounding variables. In total, the risk for having hypertension increased by 0.3% per 1 μmol/L increment in SUA level, increased by 95% for the highest vs. lowest quartile of SUA level, and increased by 111% in the hyperuricemia patients. Moreover, we found that the association was more pronounced in the male participants. There were approximately J-shaped relationships between SUA level (quartiles) and hypertension in all age groups. Higher SUA levels are positively associated with hypertension among the Chinese rural elderly. Further studies are still required to determine the relationship between SUA level and hypertension and to explore its potential biological mechanisms underlying the gender-related association in the elderly population.

ABBREVIATIONS

CVD; cardiovascular disease; BMI: body mass index; BP: blood pressure; SUA: serum uric acid; TC: total cholesterol; TG: triglycerides; HDL-C: high-density lipoprotein; LDL-C: low-density lipoprotein; FPG: fasting blood glucose; OR: odds ratio; CI: confidence interval; SD: standard deviation.

Serum uric acid is not independently associated with plasma renin activity and plasma aldosterone in hypertensive adults

BACKGROUND AND AIMS

In experimental investigations conducted in rats, raising serum uric acid (SUA) levels resulted in the stimulation of intrarenal renin expression. Studies in humans exploring the association of SUA with plasma renin activity (PRA) yielded conflicting results. Moreover, little is known about the relationship of SUA with plasma aldosterone concentration (PAC). The study aimed to assess the relationship between SUA levels, PRA, and PAC and the influence of age, gender, body mass index (BMI), and hyperuricemia on these relationships in subjects with essential hypertension (EH).

METHODS AND RESULTS

We enrolled 372 hypertensive patients (mean age 45 ± 12 years, men 67%) with uncomplicated EH that was not pharmacologically treated. The study population was divided in tertiles according to SUA levels. While PRA did not differ significantly across the three tertiles, PAC was higher in subjects belonging to the uppermost tertile of SUA than those in the lower ones (p = 0.0429); however, this difference lost statistical significance after adjustment for age, sex, BMI, and serum creatinine. Univariate correlation analyses showed significant associations of SUA with PRA (r = 0.137; p = 0.008) and PAC (r = 0.179; p < 0.001). However, these relationships were not significant after correcting for confounding factors in multiple linear regression analyses. We did not observe statistically significant effect modification by gender, age, BMI, and hyperuricemia.

CONCLUSION

SUA levels are weakly associated with PRA and PAC in adults with untreated EH. These relationships were lost after adjustment for age, sex, BMI, and serum creatinine.

Association of Serum Uric Acid Concentration with Diabetic Retinopathy and Albuminuria in Taiwanese Patients with Type 2 Diabetes Mellitus

Patients with type 2 diabetes mellitus (DM) may experience chronic microvascular complications such as diabetic retinopathy (DR) and diabetic nephropathy (DN) during their lifetime. In clinical studies, serum uric acid concentration has been found to be associated with DR and DN. The goal of this study was to evaluate the relationship between the increases in serum uric acid level and the severity of DR and albuminuria in Taiwanese patients with type 2 DM. We recorded serum uric acid concentration, the severity of DR, and the severity of albuminuria by calculating urinary albumin-to-creatinine ratio (UACR) in 385 patients with type 2 DM. In multivariate logistic regression analysis, a high uric acid concentration was a risk factor for albuminuria (odds ratio (OR), 1.227; 95% confidence interval (CI) = 1.015–1.482; p = 0.034) and DR (OR, 1.264; 95% CI = 1.084–1.473; p = 0.003). We also demonstrated that there was a higher concentration of serum uric acid in the patients with more severe albuminuria and DR. In conclusion, an increased serum uric acid level was significantly correlated with the severity of albuminuria and DR in Taiwanese patients with type 2 DM.

Association of serum uric acid levels with the risk of development or progression of albuminuria among Japanese patients with type 2 diabetes: a prospective cohort study [Diabetes Distress and Care Registry at Tenri (DDCRT 10)]

AIMS

To assess the prospective association between baseline serum uric acid level and subsequent risk of development or progression in albuminuria.

METHODS

Longitudinal data were obtained from 2518 patients with type 2 diabetes in the development cohort and registered in a Japanese diabetes registry. To assess the independent correlations between baseline serum uric acid quartiles and either the development or progression of diabetic nephropathy for 2 years, the Cox proportional hazards model was used and adjusted for potential confounders.

RESULTS

The mean patient age, body mass index, and glycated hemoglobin (HbA1c) level were 66.1 years, 24.6 kg/m(2), and 7.5 % (57.6 mmol/mol), respectively. The baseline serum uric acid levels, with mean values of 3.6, 4.9, 5.8, and 7.3 mg/dL from the first to fourth quartiles, were significantly associated with the urinary albumin/creatinine ratio at baseline (p < 0.001). Baseline uric acid levels were not significantly associated with the development of nephropathy, but they were with the progression of nephropathy. The multivariable-adjusted hazards ratios for the progression from microalbuminuria to macroalbuminuria were 2.17 [95 % confidence interval (CI) 1.15-4.08; p = 0.016], 3.04 (95 % CI 1.67-5.53; p < 0.001), and 3.56 (95 % CI 1.83-6.93; p < 0.0011) for the first, third, and fourth quartiles of serum uric acid levels, respectively, as compared to that for the second quartile. We did not observe significant association between uric acid levels and change in estimated glomerular filtration rate.

CONCLUSIONS

Low and high serum uric levels, independent of possible confounders, were associated with a subsequent risk of progression, not development, in albuminuria in type 2 diabetes patients. Therefore, serum uric acid levels may be useful for predicting the future risk of progression of microalbuminuria.

Putative Role of Cardio Metabolic Risk Among Poorly Controlled Asthmatics in South Indian Population

Mortality and morbidity attributed to asthma remains to be the biggest nightmare worldwide. Hence, the study was aimed to compare the cardio metabolic risk factors as assessed by Body mass index (BMI), waist hip ratio (WHR), serum triacylglycerol and uric acid in well controlled and poorly controlled asthmatics and to correlate these parameters with the severity of asthma. A case control study was conducted on 90 subjects who were segregated into well controlled asthmatics (n = 30) and poorly controlled asthmatics (n = 30) who were diagnosed based on Global initiative for Asthma management guidelines and healthy volunteers (n = 30). Centrifuged fasting venous blood samples were used for biochemical analysis, pulmonary function test, BMI, and waist hip ratio (WHR) were measured. The statistical analysis was done using SPSS version 17. There was a significant increase in BMI, WHR, lipid profile, serum uric acid and decrease in forced expiratory volume (FEV1), forced vital capacity (FVC), and FEV1/FVC in poorly controlled asthmatics. There was a significant association between FEV1 and serum uric acid, BMI and Triacylgycerol in poorly controlled asthmatics. Poorly controlled asthmatics have greater risk of developing cardiometabolic problems. Serum uric acid can be used as one of the severity markers in asthma to assess cardio metabolic risk.

Association between uric acid and renal function in hypertensive patients: which role for systemic vascular involvement?

The role of systemic vascular involvement in mediating the association between serum uric acid (SUA) and renal function in hypertension has not been explored. Main purpose of our study was to investigate whether morphofunctional vascular changes, assessed as carotid intima-media thickness (cIMT) and aortic pulse wave velocity (aPWV), might mediate the association between SUA and renal damage. We enrolled 523 hypertensive subjects with or without chronic kidney disease and divided population into tertiles of SUA based on sex-specific cutoff values. cIMT and aPWV were higher in uppermost SUA-tertile patients when compared to those in the lowest ones (all P < .001). Uricemia strongly correlated with cIMT and aPWV at univariate analysis (P < .001) and with cIMT after adjustment for confounders (P < .001). Adjustment for cIMT attenuated the relationship between SUA and estimated glomerular filtration rate (P = .019). Systemic vascular changes seem partially to mediate the association between SUA and renal function in hypertensive patients, regardless of kidney function.

Value of the intrarenal arterial resistivity indices and different renal biomarkers for early identification of diabetic nephropathy in type 1 diabetic patients

BACKGROUND

The aim of this study was to compare resistivity index (RI) in type 1 diabetic patients and normal controls and to evaluate whether high RI is associated with different biomarkers of diabetic nephropathy (DN) as early detection of DN offers the best chance of delaying or possibly preventing progression to end-stage renal disease.

METHODS

The study included 62 type 1 diabetic patients and 30 healthy volunteers of the same age and sex. Blood samples were taken for assessment of glycosylated hemoglobin, lipid profile and urine samples were taken for assessment of albumin/creatinine ratio, neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid binding protein (L-FABP) and kidney injury molecule-1 (Kim-1). Forty-five diabetic patients and 30 controls had a renal Doppler ultrasonography. t-Test or Mann Whitney U-test for independent variables, Pearson's or Spearman correlation analysis were used.

RESULTS

The mean age of diabetic patients was 16.3±1.5 years, and mean duration of diabetes was 9.4±2.9 years. RI, albumin/creatinine ratio, NGAL, Kim-1 and L-FABP were significantly higher in diabetics than in controls. RI, NGAL, Kim-1, and L-FABP were significantly higher in microalbuminuric compared to normoalbuminuric diabetics. In normoalbuminuric diabetics, RI, NGAL, Kim-1 and L-FABP were significantly higher compared to controls. The study revealed significant positive correlation between the RI in diabetics and both KIM-1 and albumin/creatinine ratio.

CONCLUSIONS

Increased RI and renal biomarkers in diabetics are early sensitive specific markers of DN, even preceded the development of microalbuminuria, denoting that they can be used as an early and sensitive markers for early detection of DN.

Serum uric acid levels are associated with a high risk of rapid chronic kidney disease progression among patients with type 2 diabetes: a prospective cohort study [Diabetes Distress and Care Registry at Tenri (DDCRT 12)]

Background

We assessed the prospective association between baseline serum uric acid (SUA) concentrations and consequent risk of chronic kidney disease (CKD) progression in type 2 diabetes patients.

Methods

Longitudinal data from a Japanese diabetes registry including 3454 type 2 diabetes patients were obtained. To assess the independent correlations between SUA and rapid CKD progression [i.e., 30 % reduction in estimated glomerular filtration rate (eGFR) over 2 years], participants were divided into five groups based on SUA levels: <5.0, ≥5.0-6.0, ≥6.0-7.0, ≥7.0-8.0, and ≥8.0 mg/dl. Cox proportional hazards model adjusted for potential confounders was used for analysis.

Results

After 2 years, rapid CKD progression was recognized in 169 patients (4.89 %) who showed longer duration of type 2 diabetes (15.5 vs. 13.5 years, p = 0.005); higher systolic blood pressure (142.0 vs. 138.3 mmHg, p = 0.016), SUA (6.15 vs. 5.32 mg/dl, p < 0.001), and urinary albumin-creatinine ratio (1127.4 vs. 184.7 mg/gCr, p < 0.001); and lower diastolic blood pressure (69.7 vs. 72.8 mmHg, p = 0.003). Multivariate ratios for rapid CKD progression were 1.19 (p = 0.371), 1.02 (p = 0.937), 1.18 (p = 0.625), and 3.04 (p = 0.004), respectively, for the first, third, fourth, and fifth serum UA range groups; a second group was used as a reference.

Conclusions

Higher SUA levels, independent of possible confounders, were associated with rapid eGFR decline and CKD progression in type 2 diabetes patients. SUA may be a useful biomarker for predicting future risk of rapid diabetic CKD progression.

Serum uric acid concentrations and SLC2A9 genetic variation in Hispanic children: the Viva La Familia Study

BACKGROUND

Elevated concentrations of serum uric acid are associated with increased risk of gout and renal and cardiovascular diseases. Genetic studies in adults have consistently identified associations of solute carrier family 2, member 9 (SLC2A9), polymorphisms with variation in serum uric acid. However, it is not known whether the association of serum uric acid with SLC2A9 polymorphisms manifests in children.

OBJECTIVE

The aim was to investigate whether variation in serum uric acid is under genetic influence and whether the association with SLC2A9 polymorphisms generalizes to Hispanic children of the Viva La Familia Study.

DESIGN

We conducted a genomewide association study with 1.1 million genetic markers in 815 children.

RESULTS

We found serum uric acid to be significantly heritable [h(2) ± SD = 0.45 ± 0.08, P = 5.8 × 10(-11)] and associated with SLC2A9 variants (P values between 10(-16) and 10(-7)). Several of the significantly associated polymorphisms were previously identified in studies in adults. We also found positive genetic correlations between serum uric acid and BMI z score (ρG = 0.45, P = 0.002), percentage of body fat (ρG = 0.28, P = 0.04), fat mass (ρG = 0.34, P = 0.02), waist circumference (ρG = 0.42, P = 0.003), and waist-to-height ratio (ρG = 0.46, P = 0.001).

CONCLUSIONS

Our results show that variation in serum uric acid in Hispanic children is under considerable genetic influence and is associated with obesity-related phenotypes. As in adults, genetic variation in SLC2A9 is associated with serum uric acid concentrations, an important biomarker of renal and cardiovascular disease risk, in Hispanic children.

Estrogen receptor β signaling induces autophagy and downregulates Glut9 expression

Glut9 is highly expressed in the human kidney proximal convoluted tubular and plays a crucial role in the regulation of plasma urate levels. The gene effects were stronger among women. Our results show that 17-β-estradiol (E2) through ER (estrogen receptor) β downregulates Glut9 protein expression on human renal tubular epithelial cell line (HK2). Intriguingly, E2 does not affect the expression of Glut9 mRNA. ERβ is linked to PTEN, the PTEN gene negatively regulates the PI3K/AKT pathway, and the PI3K/AKT pathway inhibition may lead to autophagy. Further study indicates that ERβ may affect the expression of Glut9 though autophagy.

No development of hypertension in the hyperuricemic liver-Glut9 knockout mouse

Urate is the metabolic end point of purines in humans. Although supra-physiological plasma urate levels are associated with obesity, insulin resistance, dyslipidemia, and hypertension, a causative role is debated. We previously established a mouse model of hyperuricemia by liver-specific deletion of Glut9, a urate transporter that provides urate to the hepatocyte enzyme uricase. These LG9 knockout mice show mild hyperuricemia (120 μmol/l), which can be further increased by the urate precursor inosine. Here, we explored the role of progressive hyperuricemia on the cardiovascular function. Arterial blood pressure and heart rate were periodically measured by telemetry over 6 months in LG9 knockout mice supplemented with incremental amounts of inosine in a normal chow diet. This long-term inosine treatment elicited a progressive increase in uricemia up to 300 μmol/l; however, it did not modify heart rate or mean arterial blood pressure in LG9 knockout compared with control mice. Inosine treatment did not alter cardiac morphology or function measured by ultrasound echocardiography. However, it did induce mild renal dysfunction as revealed by higher plasma creatinine levels, lower glomerular filtration rate, and histological signs of chronic inflammation and fibrosis. Thus, in LG9 knockout mice, inosine-induced hyperuricemia was not associated with hypertension despite partial renal deficiency. This does not support a direct role of urate in the control of blood pressure.

The urinary cytokine/chemokine signature of renal hyperfiltration in adolescents with type 1 diabetes

OBJECTIVE

Urinary cytokine/chemokine levels are elevated in adults with type 1 diabetes (T1D) exhibiting renal hyperfiltration. Whether this observation extends to adolescents with T1D remains unknown. Our first objective was to determine the relationship between hyperfiltration and urinary cytokines/chemokines in normotensive, normoalbuminuric adolescents with T1D using GFR(cystatin). Our second aim was to determine the relationship between urine and plasma levels of inflammatory biomarkers, to clarify the origin of these factors.

METHODS

Urine and serum cytokines/chemokines (Luminex platform) and GFR(cystatin) were measured in normofiltering (n = 111, T1D-N, GFR<135 ml/min/1.73 m(2)) and hyperfiltering (n = 31, T1D-H, GFR ≥ 135 ml/min/1.73 m(2)) adolescents with T1D (ages 10-16), and in age and sex matched healthy control subjects (HC, n = 59).

RESULTS

We noted significant step-wise increases in urinary cytokine/chemokine excretion according to filtration status with highest levels in T1D-H, with parallel trends in serum analyte concentrations. After adjusting for serum glucose at the time of sampling, differences in urinary cytokine excretion were not statistically significant. Only serum IL-2 significantly differed between HC and T1D (p = 0.0076).

CONCLUSIONS

Hyperfiltration is associated with increased urinary cytokine/chemokine excretion in T1D adolescents, and parallel trends in serum cytokine concentration. The GFR-associated trends in cytokine excretion may be driven by the effects of ambient hyperglycemia. The relationship between hyperfiltration, glycemia, and variations in serum and urine cytokine expression and their impact on future renal and systemic vascular complications requires further study.

UPLC-based metabonomic applications for discovering biomarkers of diseases in clinical chemistry

OBJECTIVES

Metabonomics is a powerful and promising analytic tool that allows assessment of global low-molecular-weight metabolites in biological systems. It has a great potential for identifying useful biomarkers for early diagnosis, prognosis and assessment of therapeutic interventions in clinical practice. The aim of this review is to provide a brief summary of the recent advances in UPLC-based metabonomic approach for biomarker discovery in a variety of diseases, and to discuss their significance in clinical chemistry.

DESIGN AND METHODS

All the available information on UPLC-based metabonomic applications for discovering biomarkers of diseases were collected via a library and electronic search (using Web of Science, Pubmed, ScienceDirect, Springer, Google Scholar, etc.).

RESULTS

Metabonomics has been used in clinical chemistry to identify and evaluate potential biomarkers and therapeutic targets in various diseases affecting the liver (hepatocarcinoma and liver cirrhosis), lung (lung cancer and pneumonia), gastrointestinal tract (colorectal cancer) and urogenital tract (prostate cancer, ovarian cancer and chronic kidney disease), as well as metabolic diseases (diabetes) and neuropsychiatric disorders (Alzheimer's disease and schizophrenia), etc.

CONCLUSIONS

The information provided highlights the potential value of determination of endogenous low-molecular-weight metabolites and the advantages and potential drawbacks of the application of UPLC-based metabonomics in clinical setting.

Dietary sugars and cardiometabolic risk: systematic review and meta-analyses of randomized controlled trials of the effects on blood pressure and lipids

BACKGROUND

Dietary sugars have been suggested as a cause of obesity, several chronic diseases, and a range of cardiometabolic risk factors, but there is no convincing evidence of a causal relation between sugars and risk factors other than body weight.

OBJECTIVE

We conducted a systematic review and meta-analysis of randomized controlled trials that examined effects of the modification of dietary free sugars on blood pressure and lipids.

DESIGN

Systematic searches were conducted in OVID Medline, Embase, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Web of Science databases (to August 2013) to identify studies that reported intakes of free sugars and at least one lipid or blood pressure outcome. The minimum trial duration was 2 wk. We pooled data by using inverse-variance methods with random-effects models.

RESULTS

A total of 39 of 11,517 trials identified were included; 37 trials reported lipid outcomes, and 12 trials reported blood pressure outcomes. Higher compared with lower sugar intakes significantly raised triglyceride concentrations [mean difference (MD): 0.11 mmol/L; 95% CI: 0.07, 0.15 mmol/L; P < 0.0001], total cholesterol (MD: 0.16 mmol/L; 95% CI: 0.10, 0.24 mmol/L; P < 0.0001), low-density lipoprotein cholesterol (0.12 mmol/L; 95% CI: 0.05, 0.19 mmol/L; P = 0.0001), and high-density lipoprotein cholesterol (MD: 0.02 mmol/L; 95% CI: 0.00, 0.03 mmol/L; P = 0.03). Subgroup analyses showed the most marked relation between sugar intakes and lipids in studies in which efforts were made to ensure an energy balance and when no difference in weight change was reported. Potential explanatory factors, including a weight change, in most instances explained <15% of the heterogeneity between studies (I(2) = 36-75%). The effect of sugar intake on blood pressure was greatest in trials ≥8 wk in duration [MD: 6.9 mm Hg (95% CI: 3.4, 10.3 mm Hg; P < 0.001) for systolic blood pressure and 5.6 mm Hg (95% CI: 2.5, 8.8 mm Hg; P = 0.0005) for diastolic blood pressure].

CONCLUSIONS

Dietary sugars influence blood pressure and serum lipids. The relation is independent of effects of sugars on body weight. Protocols for this review were registered separately for effects of sugars on blood pressure and lipids in the PROSPERO International prospective register of systematic reviews as PROSPERO 2012: CRD42012002379 and 2012: CRD42012002437, respectively.

High-normal serum uric acid predicts the development of chronic kidney disease in patients with type 2 diabetes mellitus and preserved kidney function

AIMS

We evaluated whether high-normal serum uric acid (SUA) levels can predict the development of chronic kidney disease (CKD) in patients with type 2 diabetes mellitus and preserved kidney function at baseline.

METHODS

This was a retrospective observational longitudinal study of patients presenting at the Department of Endocrinology and Metabolism, Pusan National University Hospital. A total of 512 patients with type 2 diabetes mellitus and preserved kidney function (estimated glomerular filtration rate [eGFR] ≥ 60 mL/min/1.73 m(2)) and normouricemia were included. The main outcome was development of CKD of stage 3 or greater. The patients were divided into four groups according to quartiles of SUA levels.

RESULTS

During the follow-up period, 62 (12.1%) patients had progressed to CKD 3 or greater. The group with the highest-normal range of SUA (Q4) showed a higher cumulative incidence of CKD stage 3 or greater than that of the other lower quartiles (Q4 vs. Q3; P = 0.037, Q4 vs. Q2; P<0.001, Q4 vs. Q1; P<0.001). In a univariate analysis, Q4 was significantly associated with the development of CKD 3 or greater (log-rank statistic, 31.93; P<0.001). In a multivariate analysis, Q4 (hazard ratio, 2.97; 95% confidence interval, 1.15-7.71; P = 0.025) showed a significant association with CKD 3 or greater.

CONCLUSIONS

High-normal SUA may predict the occurrence of CKD stage 3 or greater in patients with type 2 diabetes mellitus and preserved kidney function.