Increasing obstructive sleep apnea risk is associated with albuminuria in Korean adults: cross-sectional analysis.

Several studies have shown an association between albuminuria and obstructive sleep apnea (OSA). However, studies on the relationship between the STOP-BANG questionnaire that can screen for OSA and microalbuminuria are still insufficient. Therefore, this study attempted to clarify the relationship between microalbuminuria and OSA risk using the STOP-BANG questionnaire in Korean adults. A total of 7478 participants (3289 men and 4189 women) aged over 40 were enrolled in the Korean National Health and Nutrition Examination Survey from 2019 to 2020. STOP-BANG questionnaire to screen OSA was obtained from subjects. The urinary albumin/creatinine ratio (ACR) and proteinuria were measured via a single dipstick to evaluate renal function. The high OSA risk group had a higher mean ACR value than the low OSA risk group (36.8 ± 172.2 vs 17.7 ± 82.5; P < 0.001). The proportion of subjects with values of 30 ≤ ACR < 300 mg/g (11.9% vs 6.1%; P < 0.001) and ACR > 300 mg/g (2.1% vs 0.7%; P < 0.001) was significantly higher in high OSA risk group. Multivariate logistic regression results confirmed that microalbuminuria (OR 1.279, 95% confidence interval (CI) 1.068-1.532, P = 0.008) was significantly correlated with high OSA risk. In addition, significant correlation with high OSA risk was also found in macroalbuminuria (OR 1.684, 95% CI 1.073-2.530, P = 0.022) and proteinuria (OR 1.355, 95% CI 1.030-1.783, P = 0.030). We confirmed a significant correlation between high OSA risk and albuminuria/proteinuria in Korean adults. Therefore, renal function evaluation is required in high OSA risk patients, and OSA diagnosis through PSG test and treatment is necessary.

Study of Neutrophil Gelatinase Associated Lipocalin and Kidney Injury Molecule-1 in Patients with Type 2 Diabetes Mellitus Nephropathy.

BACKGROUND: There is a need for accurate and rapid biomarkers for the early diagnosis of diabetic nephropathy (DN). We aimed to study the accuracy of urinary neutrophil gelatinase-associated lipocalin (uNGAL), urinary kidney injury molecule-1 (uKIM-1), and blood NGAL (bNGAL) in type 2 diabetics as biomarkers for diagnosis of DN. METHODS: The study was a retrospective case-control study that included 30 control subjects, 40 diabetics with normo-albuminuria < 30 mg/g and eGFR > 60 mL/minute/1.73 m2, and 30 diabetics with albuminuria > 30mg/g and eGFR < 60mL/minute/1.73 m2. Blood and urine samples were obtained to determine levels of bNGAL, uNAGAL, and uKIM1. RESULTS: There was a significant increase in bNGAL, uNGAL, uKIM 1, uNGAL/creatinine and uKIM 1/creatinine among diabetics with albuminuria compared to diabetics with normoalbuminuria and normal control (p < 0.001 for all markers). For diagnosis of early DN, both bNGAL and uKIM 1 had sensitivity and specificity of 100% for each at cutoff values of 322.5 pg/mL and 74.25 ng/mL, respectively. uNGAL had a sensitivity of 97.5% and a spec-ificity of 100% at a cutoff point of 565 ng/mL. uKIM1/creatinine at a cutoff of 51.2 had a sensitivity of 100% and specificity of 100%. CONCLUSIONS: The present study highlights the accuracy of urinary KIM1 and NGAL and blood NGAL as biomarkers for the diagnosis of nephropathy in the early stage of diabetic nephropathy. There were positive correlations with kidney function tests creatinine, blood urea nitrogen, and the presence of albuminuria.

Urine Albumin Measurements in Clinical Diagnostics.

BACKGROUND: Measurement of urine albumin is critical for diagnosis, risk classification, and monitoring of chronic kidney disease (CKD). Guidelines recommend clinical decision cutoffs for the urine albumin-to-creatinine ratio (ACR) of 30 and 300 mg/g (3 and 30 mg/mmol). However, differences among manufacturers' routine urine albumin measurement procedures have been found to exceed 40%, suggesting CKD diagnosis and risk classification may vary depending upon the specific measurement procedure implemented in the laboratory. CONTENT: This review discusses urine albumin pathophysiology and clinical practice guideline recommendations for CKD. The review also provides recommendations for urine specimen collection and storage, and results reporting for the ACR. Recent advances in measurement techniques and development of reference systems intended to facilitate standardization of urine albumin measurements are reviewed. SUMMARY: Urine albumin is an important measurement procedure used for diagnosis, risk classification, and management of CKD. Urine albumin results should be reported as the ACR using quantitative measurement procedures. Random urine collections used for albuminuria screening should be followed by confirmation with first morning void collections to reduce variation and increase diagnostic accuracy for urine albumin measurement. Most measurement procedures utilize immunoturbidimetric or immunonephelometric techniques. However, results vary significantly among measurement procedures, potentially resulting in differences in classification or risk assessment for CKD. The National Institute for Standards and Technology (NIST) and other laboratories are developing reference systems, including liquid chromatography-tandem mass spectrometry candidate reference measurement procedures and reference materials, to enable standardization of routine measurement procedures.

Urinary Prostaglandin E2 Excretion and the Risk of Cardiovascular and Kidney Disease.

BACKGROUND: Inhibition of prostaglandin synthesis by nonsteroidal anti-inflammatory drugs is associated with cardiovascular mortality and kidney disease. This study hypothesizes that urinary prostaglandin E2 (PGE2) and PGE2 metabolite (PGEM) excretions are markers of cardiovascular and kidney health, because they reflect both systemic and kidney-derived PGE2 production. METHODS AND RESULTS: PGE2 and PGEM were measured in spot urine samples from 2291 participants (≥55 years old) of the population-based Rotterdam Study. Urinary PGE2 and PGEM excretions were analyzed using linear regression analyses to identify cross-sectional associations with cardiovascular risk factors and baseline estimated glomerular filtration rate (eGFR). Longitudinal associations with cardiovascular mortality and kidney outcomes (eGFR <60 or <45 mL/min per 1.73 m2 and the composite outcome 40% eGFR loss or kidney failure) were assessed with Cox regression. Urinary PGE2 and PGEM excretions were higher with increasing age, lower eGFR, smoking, diabetes, and albuminuria. A 2-fold higher urinary PGE2 and PGEM excretion was associated with a higher risk of cardiovascular mortality (28 825 patient-years; 160 events; PGE2 hazard ratio [HR], 1.27, [95% CI, 1.06-1.54]; PGEM HR, 1.36 [95% CI, 1.10-1.67]). Higher PGE2 excretions were also associated with a higher risk of incident eGFR <60 mL/min per 1.73 m2 (31 530 person-years; 691 events; HR, 1.13 [95% CI, 1.02-1.25]) with similar HRs for the other kidney outcomes. CONCLUSIONS: Urinary PGE2 and PGEM excretions are novel markers for the presence and progression of cardiovascular and kidney disease. Future studies should address whether these associations are causal and can be targeted to improve cardiovascular and kidney outcomes.

A comprehensive analysis of albuminuria in canine chronic kidney disease.

BACKGROUND: Albuminuria, an important marker of decreased kidney function in chronic kidney disease (CKD), is not routinely used for CKD detection or proteinuria appearance. Its relationships with biochemical parameters and blood pressure in dogs are poorly understood. OBJECTIVES: This study aimed to evaluate the relationship of albuminuria with various CKD markers, its correlation with the urinary protein to creatinine ratio (UPC), and hypertension in dogs with early stages of CKD. It also sought to determine the usability of the urinary albumin to creatinine ratio (UAC) for CKD screening. METHODS: The study reviewed records of 102 dogs, categorising them into four groups based on disease status. UAC and UPC ratio, biochemistry and haematology variables, age, and systolic blood pressure were determined. RESULTS: The Pearson's correlation coefficient between log-transformed values of UPC and UAC was r = 0.902 (95% CI: 0.87 to 0.93). Median UAC ratio values were 2.1 mg/g for the Healthy control group (n = 17), 54.2 mg/g for early stages CKD (n = 42), 5.8 mg/g for Acute sick control (n = 30), and 104 mg/g for Chronic sick control (n = 13). Thresholding UAC ratio as an indicator for impaired kidney function with the threshold of 10 mg/g (established based on the receiver operating characteristic curve) had a sensitivity 81.8%, specificity of 89.4%, positive predictive value (PPV) 90%, and negative predictive value (NPV) 80.1%. The correlation of UAC with biochemistry and haematology variables was statistically significant; for SDMA (µg/L), it was r = 0.566 and for other variables, it was weak to moderate. UAC was markedly elevated in cases of severe hypertension. CONCLUSIONS: UAC ratio was significantly different among dogs with impaired and not impaired kidney function. The correlation strength for the UAC and UPC ratios was high. UAC ratio may be a promising marker for proteinuria analysis in dogs with CKD or other kidney function alterations.

Development of a reference interval for urinary ammonia-to-creatinine ratio in feline patients.

BACKGROUND: Disruption of acid-base homeostasis can lead to many clinical problems. Ammonia excretion by the kidneys is critical to maintaining acid-base homeostasis through bicarbonate production. Measurement of ammonia excretion may help determine if the kidneys are properly functioning in maintaining acid-base balance. Reference intervals are essential tools for clinical decision-making but do not currently exist for urinary ammonia-to-creatinine ratio (UACR) in feline patients. OBJECTIVE: This study aimed to generate a reference interval (RI) for UACR in healthy adult cats. METHODS: The study used samples from client-owned adult healthy cats that presented to the University of Florida Primary Care and Dentistry service (n = 92). Physical examination, serum biochemistry, urinalysis, urine ammonia, and creatinine concentrations were measured. Cats were excluded if there were significant abnormalities in their urinalysis or biochemistry panel. The RI for UACR was calculated according to the recommendation of the American Society for Veterinary Clinical Pathology. The UACR was evaluated for correlation with serum bicarbonate, weight, age, and sex. RESULTS: The RI for UACR was 3.4-20.7 with 90% confidence intervals for the lower and upper limits of (3.0-3.7) and (16.0-23.7), respectively. No significant correlation with age, sex, or weight was found. There was no discernable relationship between serum bicarbonate and UACR. CONCLUSIONS: Establishing an RI for UACR in healthy adult cats will allow further studies to determine if changes in UACR are observed during specific disease states.

Urine albumin-to-creatinine ratio diurnal variation rate predicts outcomes in idiopathic membranous nephropathy.

BACKGROUND: Idiopathic membranous nephropathy (IMN) is a leading cause of end-stage renal disease (ESRD). The purpose of this study was to evaluate whether urinary albumin-to-creatinine ratio (UACR) diurnal variation rate calculated by spot urinary protein test predicts 1-year nephrotic outcomes as a biomarker of proteinuria severity in patients with IMN. METHODS: Patients' baseline demographics, blood and urinary biomarkers, and clinical and pathological characteristics were collected retrospectively. Urine samples were collected at 7:00 (before breakfast) and 19:00 (after dinner) to calculate the UACR diurnal variation rate. A prediction model for no remission (NR) was developed statistically based on differences between prognosis groups. Receiver operating characteristic curve (ROC) analysis was performed to evaluate prediction abilities and determine optimal cut-off points of the model and UACR diurnal variation rate alone. RESULTS: The formula for calculating the probability of NR was exp(L)/(1 + exp(L)), where the linear predictor L = - 22.038 + 0.134 × Age (years) + 0.457 × 24-h urinary protein + 0.511 × blood urea nitrogen (BUN) + 0.014 × serum uric acid (SUA) + 2.411 if glomerular sclerosis + 0.816 × fasting blood glucose (FBG)-0.039 × UACR diurnal variation rate (%). Optimal cut-off points for NR prediction by the final model and UACR diurnal variation rate alone were 0.331 and 58.5%, respectively. Sensitivity and specificity were 0.889 and 0.859 for the final model, and 0.926 and 0.676 for UACR diurnal variation rate alone. CONCLUSION: UACR diurnal variation using spot urinary protein is a simpler way to predict nephrotic outcomes and is a highly sensitive screening tool for identifying patients who should undergo further comprehensive risk assessment.

Trajectory of Urine Albumin-Creatinine Ratio in Patients with Acute Heart Failure.

INTRODUCTION: Albuminuria is prevalent in patients with chronic heart failure and is a risk factor for disease progression. However, its clinical meaning in acute heart failure remains elusive. This study analyzed the trajectory of urine albumin to creatinine ratio (UACR) between admission and discharge and its association with decongestion. METHODS: In this prospective observational study, 63 patients were enrolled. UACR, B-type natriuretic peptide (BNP), and clinical congestion score (CCS) were obtained at admission and discharge. We used linear mixed regression analysis to compare changes in the natural logarithm of UACR (logUACR) and its association with changes in markers of decongestion. Estimates were reported as least squares mean with their respective 95% CIs. RESULTS: The median age of the study population was 87 years, 68.5% were women, and 69.8% had a left ventricular ejection fraction >50%. LogUACR at discharge significantly decreased in the overall population compared to admission (Δ -0.47, 95% CI: -0.78 to -0.15, p value = 0.003). The magnitude of UACR drop at discharge was associated with changes in surrogate markers of decongestion. Patients who showed a greater reduction in BNP at discharge exhibited a greater reduction in UACR (p = 0.016). The same trend was also found with clinical decongestion, as assessed by changes in CCS, however, without achieving statistical significance (p = 0.171). UACR change at discharge was not associated with changes in serum creatinine (p value = 0.923). CONCLUSION: In elderly patients with AHF and volume overload, the level of UACR significantly decreased upon discharge compared to admission. This reduction in UACR was closely linked to decreases in BNP.

Determination of pentoxifylline efficacy on microalbuminuria in patients with type-2 diabetes.

BACKGROUND: Diabetic nephropathy is a clinical syndrome characterized by persistent albuminuria and progressive impairment in renal function. Pentoxifylline is a non-specific inhibitor of phosphodiesterase with anti-inflammatory properties which may have therapeutic potency in patients with diabetic kidney disease. OBJECTIVE: The present study is aimed at evaluating the efficacy of pentoxifylline as a treatment strategy for alleviating the microalbuminuria in type-2 diabetic patients with nephropathy. METHODS: This double-blind randomized clinical trial was performed on outpatients with type 2 diabetic nephropathy who presented urine albumin excretion of 30-300 mg per 24 hours on at least three consecutive occasions. A total of 58 patients were randomly assigned to the treatment and control groups. The treatment group (n=29) received pentoxifylline (400 mg/day) for 3 months in addition to the standard drugs for diabetic nephropathy (Raas blockers), while the control group (n=29) received placebo as add-on therapy. Finally, urine albumin test was measured before and after 3 months of treatment and compared between the two groups. RESULTS: Before the intervention, no significant difference in the levels of albuminuria was observed between the two groups (153.21±130.80 mg/day vs. 159.93 ±130.45; p=0.845); but after 12 weeks of treatment, albuminuria in the treatment group was significantly reduced compared to the placebo group (29.59 ±27.88 mg/day vs. 160.48±129.53 mg/day; p<0.0001). At the end of the study, the response rate to treatment (more than 50% reduction in albuminuria) was 89.7% in the pentoxifylline group, while no response to treatment was observed in the placebo group (p<0.0001). CONCLUSIONS: Pentoxifylline as add-on therapy to the conventional treatment (Raas blockers) may reduce the microalbuminuria in patients with diabetic nephropathy without any side effects.

Reference values for urinary protein, albumin, beta 2-microglobulin, and the alpha 1-microglobulin-to-creatinine ratio in Japanese children.

BACKGROUND: The importance of the ratio of creatinine to urinary protein, albumin, and low-molecular weight protein as a urinary marker in chronic kidney disease patients is widely recognized. However, no reference values have hitherto been established for these markers in Japanese children. The present study aimed to establish the reference values for these urinary markers in Japanese children. METHODS: The first morning urine was randomly collected from 1712 pupils aged ≥ 3 to < 18 years during school and kindergarten mass urinary screenings. The upper limit of the reference values was set at the 97.5th percentile of the creatinine ratio per marker. RESULTS: The urinary protein-to-creatinine ratio (PCR), urinary albumin-to-creatinine ratio (ACR), urinary beta 2-microglobulin-to-creatinine ratio (BMCR), and urinary alpha 1-microglobulin-to-creatinine ratio (AMCR) showed an age-related decrease at the 50th percentile reflecting an age-related increase in urinary creatinine. The appropriate reference value for the PCR and ACR was 0.12 g/gCr and 35 mg/gCr, respectively, in the entire cohort. The appropriate reference value for the BMCR was 0.5 µg /mgCr for age ≥ 3 to < 6 years and 0.35 µg/mgCr for age 6 years or older. The appropriate reference value for the AMCR was 5.0 µg/mgCr for age ≥ 3 to < 6 years and 3.5 µg /mgCr for age 6 years or older. CONCLUSION: The present study was the first to determine appropriate reference values for the PCR, ACR, BMCR, and AMCR based on an analysis of the first morning urine samples of a large number of children.

Proteinuria, measured or estimated albuminuria for risk prediction in patients with chronic kidney disease?

BACKGROUND: Although albuminuria is the gold standard for defining chronic kidney disease (CKD), total proteinuria has also been widely used in real-world clinical practice. Moreover, the superiority of the prognostic performance of albuminuria over proteinuria in patients with CKD remains inconclusive. Therefore, we aimed to compare the predictive performances of albuminuria and proteinuria in these patients. METHODS: From the Korean Cohort Study for Outcome in Patients with CKD we included 2099 patients diagnosed with CKD grades 1-5 who did not require kidney replacement therapy. We measured the spot urine albumin:creatinine ratio (mACR) and protein:creatinine ratio (PCR) and estimated the ACR (eACR) using the PCR. Kidney failure risk equation (KFRE) scores were calculated using the mACR, PCR and eACR. The primary outcome was the 5-year risk of kidney failure with replacement therapy (KFRT). RESULTS: The eACR significantly underestimated mACR in patients with low albuminuria levels. The time-dependent area under the receiver operating characteristics curve showed excellent predictive performance for all KFRE scores from the mACR, PCR and eACR. However, eACR was inferior to mACR based on the continuous net reclassification index (cNRI) and integrated discrimination improvement index (IDI) in all CKD cause groups, except for the group with an unclassified aetiology. Moreover, the cNRI and IDI statistics indicated that both eACR and PCR were inferior to mACR in patients with low albuminuria (<30 mg/g). Conversely, the predictive performance of PCR was superior in severe albuminuria and nephrotic-range proteinuria, in which the IDI and cNRI of the PCR were greater than those of the mACR. CONCLUSIONS: The mACR, eACR and PCR showed excellent performance in predicting KFRT in patients with CKD. However, eACR was inferior to mACR in patients with low albuminuria, indicating that measuring rather than estimating albuminuria is preferred for these patients.

Cardiovascular and renal outcomes with varying degrees of kidney disease in high-risk people with type 2 diabetes: An epidemiological analysis of data from the AMPLITUDE-O trial.

AIMS: To estimate the incidence of a major adverse cardiovascular event (MACE) and a composite kidney outcome across estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR) levels, and to determine whether efpeglenatide's effect varies with these indices. MATERIALS AND METHODS: AMPLITUDE-O trial data were used to estimate the relationship of eGFR, UACR, and Kidney Disease Improving Global Outcomes (KDIGO) category to the hazard of MACE and the kidney composite. Interactions on these outcomes between eGFR and the UACR, and between each of these variables and efpeglenatide were also assessed. RESULTS: Baseline eGFR and UACR were available for 3983 participants (mean age 64.5 years). During a median follow-up of 1.8 years, the hazards of MACE and the kidney composite for the lowest versus highest eGFR third were 1.6 (95% confidence interval [CI] 1.2, 2.2) and 2.3 (95% CI 1.9, 2.8), respectively. The hazards for the highest versus the lowest UACR third were 2.3 (95% CI 1.8, 3.1) and 18.0 (95% CI 12.7, 25.5), respectively, and for the high- versus low-risk KDIGO categories the hazards were 2.4 (95% CI 1.8, 3.1) and 16.0 (95% CI 11.6, 22.0), respectively. eGFR and UACR were independent determinants of both outcomes, but negatively interacted with each other for the kidney outcome. Efpeglenatide's effect on both outcomes did not vary with any kidney disease measure (all interaction p values ≥0.26). CONCLUSIONS: In high-risk people with diabetes, eGFR, UACR, and KDIGO category have different relationships to incident cardiovascular and kidney outcomes. The beneficial effect of efpeglenatide on these outcomes is independent of kidney-related risk category.

Effect of tirzepatide on albuminuria levels and renal function in patients with type 2 diabetes mellitus: A systematic review and multilevel meta-analysis.

AIM: The present systematic review aimed to summarize the available evidence from published randomized controlled trials (RCTs) regarding the effect of tirzepatide on albuminuria levels and renal function in patients with type 2 diabetes mellitus. MATERIALS AND METHODS: Medline (via PubMed), Cochrane Library and Scopus were searched until 20 October 2023. Double-independent study selection, data extraction and quality assessment were performed. Evidence was pooled with a three-level mixed-effects meta-analysis. RESULTS: In total, 9533 participants from eight RCTs were analysed. All RCTs had a low risk of bias, according to the Cochrane Collaboration tool (RoB2). Tirzepatide was associated with a significantly greater reduction in urine albumin-to-creatinine ratio compared with controls [mean difference (MD) -26.9%; 95% confidence interval (CI) (-34.76, -19.04); p < .001; level of evidence (LoE) moderate]. This effect remained significant in participants with baseline urine albumin-to-creatinine ratio ≥30 mg/g [MD -41.42%; 95% CI (-54.38, -28.45); p < .001; LoE moderate]. Based on subgroup analysis, the comparative effect of tirzepatide was significant against placebo and the insulin regimen, whereas no difference was observed compared with semaglutide. The beneficial effect of tirzepatide on albuminuria levels remained significant across all investigated doses (5, 10 and 15 mg), showing a dose-response relationship. A neutral effect was observed on the estimated glomerular filtration rate [MD 0.39 ml/min/1.73m2 ; 95% CI (-0.64, 1.42); p = .46; LoE moderate]. CONCLUSION: Our findings suggest that tirzepatide probably leads to a significant reduction in albuminuria across all administered doses, while its use is associated with a neutral effect on creatinine clearance as a measure of renal function.

Impact of Finerenone-Induced Albuminuria Reduction on Chronic Kidney Disease Outcomes in Type 2 Diabetes : A Mediation Analysis.

BACKGROUND: In patients with chronic kidney disease (CKD) and type 2 diabetes (T2D), finerenone, a nonsteroidal mineralocorticoid receptor antagonist, reduces cardiovascular and kidney failure outcomes. Finerenone also lowers the urine albumin-to-creatinine ratio (UACR). Whether finerenone-induced change in UACR mediates cardiovascular and kidney failure outcomes is unknown. OBJECTIVE: To quantify the proportion of kidney and cardiovascular risk reductions seen over a 4-year period mediated by a change in kidney injury, as measured by the change in log UACR between baseline and month 4. DESIGN: Post hoc mediation analysis using pooled data from 2 phase 3, double-blind trials of finerenone. (ClinicalTrials.gov: NCT02540993 and NCT02545049). SETTING: Several clinical sites in 48 countries. PATIENTS: 12 512 patients with CKD and T2D. INTERVENTION: Finerenone and placebo (1:1). MEASUREMENTS: Separate mediation analyses were done for the composite kidney (kidney failure, sustained ≥57% decrease in estimated glomerular filtration rate from baseline [approximately a doubling of serum creatinine], or kidney disease death) and cardiovascular (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure) outcomes. RESULTS: At baseline, median UACR was 514 mg/g. A 30% or greater reduction in UACR was seen in 3338 (53.2%) patients in the finerenone group and 1684 (27.0%) patients in the placebo group. Reduction in UACR (analyzed as a continuous variable) mediated 84% and 37% of the treatment effect on the kidney and cardiovascular outcomes, respectively. When change in UACR was analyzed as a binary variable (that is, whether the guideline-recommended 30% reduction threshold was met), the proportions mediated for each outcome were 64% and 26%, respectively. LIMITATION: The current findings are not readily extendable to other drugs. CONCLUSION: In patients with CKD and T2D, early albuminuria reduction accounted for a large proportion of the treatment effect against CKD progression and a modest proportion of the effect against cardiovascular outcomes. PRIMARY FUNDING SOURCE: Bayer AG.

Effect of weight loss on proteinuria in adults with type 2 diabetes: A real-world study.

AIMS: To assess the impact of weight loss on proteinuria in patients with type 2 diabetes (T2DM) in real-world settings. METHODS: A total of 1054 participants were categorized based on weight change from baseline to one-year follow-up: weight gain (≥3%), stable weight, or weight loss (≥3%). Proteinuria outcomes were defined as urinary albumin/creatinine ratio (UACR) progression (≥30 % increase), UACR regression (≥30 % reduction), or UACR stable. Ordered logistic regression analysis evaluated the relationship between weight loss and UACR regression. RESULTS: Of the 1054 participants, 44.5 % were overweight, and 24.1 % were obese. Patients with obesity were at higher risk of developing proteinuria (OR, 1.783; 95 %CI, 1.195 to 2.659). Weight loss was associated with an 83.3 % increase in UACR regression compared to weight gain (OR, 1.833; 95 % CI, 1.262 to 2.663; P = 0.001). This association remained consistent across most subgroups and stronger in males (P for interaction = 0.023), with a 6 % UACR regression for every 1 kg weight loss (OR, 1.06; 95 % CI, 1.02 to 1.10; P = 0.003). CONCLUSIONS: Our real-world study reveals that weight reduction is associated with UACR regression in patients with T2DM, regardless of the approach used for weight management, and the association was much stronger in males.

Upregulation of the protein kinase Lyn is associated with renal injury in type 2 diabetes patients.

BACKGROUND: The role of inflammation in the pathogenesis of type 2 diabetes mellitus (T2DM) is well established. Lyn, a member of the nonreceptor protein tyrosine kinase Src family, has been reported to modulate inflammatory signaling pathways. METHODS: Lyn expression was assessed in kidney biopsies of 11 patients with diabetic kidney disease (DKD) and in kidney tissues of streptozotocin (STZ)-induced DKD mice. 102 recruited T2DM patients were divided into three groups: normoalbuminuria, microalbuminuria and macroalbuminuria. Twenty-one healthy volunteers were recruited as a control group. Clinical data, blood and urine samples of all individuals were collected for analysis. RESULTS: Lyn expression was augmented in the kidneys of DKD patients and STZ-induced diabetic mice. Compared with control and normoalbuminuria groups, both mRNA and protein expression of Lyn in peripheral blood mononuclear cells (PBMCs) in the macroalbuminuria group were significantly increased (p < .05). Elevated Lyn levels were independently related to urine albumin/urine creatinine ratio and were positively associated with key inflammatory factors, namely interleukin-1ß, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Additionally, Lyn exhibited a noteworthy connection with renal tubular injury indicators, specifically urinary neutrophil gelatinase-associated lipocalin and urinary retinol binding protein. ROC curve analysis showed that Lyn could predict albuminuria in diabetic patients with an area under the curve of 0.844 (95% CI: 0.764-0.924). CONCLUSION: Lyn levels in PBMCs exhibited a positive correlation with the severity of albuminuria, renal tubular damage, and inflammatory responses. Hence, Lyn may be a compelling candidate for predicting albuminuria levels in diabetes.

Burden and predictors of diabetic kidney disease in an adult Ugandan population with new-onset diabetes.

BACKGROUND: Despite the growing evidence of diabetic kidney disease (DKD) in adult patients with long-standing diabetes in sub-Saharan Africa, data on its burden and correlates in adult African patients with new-onset diabetes are limited. We, therefore, undertook this study to determine the burden and predictors of DKD in an adult population with new-onset diabetes in Uganda. METHODS: We collected data on the relevant sociodemographic, clinical, anthropometric, and metabolic characteristics in 519 participants with newly diagnosed diabetes recruited from seven tertiary hospitals. A spot mid-stream urine sample was collected for determination of the urine albumin creatinine ratio (UACR) using Clinitek® microalbumin strips and a point-of-care Clinitek® status analyser. The estimated glomerular filtration rate (e-GFR) was determined using the Chronic Kidney Disease Epidemiology formula. The presence of DKD was defined as a spot UACR ≥ 3 mg/mmol with or without an e-GFR < 60 ml/min/1.73m2. RESULTS: The median (IQR) age, UACR, and e-GFR of the participants were 48 years (39-57), 2.27 mg/mmol (1.14-3.41), and 121.8 ml/min/1.73m2 (105.4-133.9). UACR ≥ 3 mg/mmol and e-GFR < 60 ml/min/1.73m2 was noted in 175 (33.7%) and 7 (1.4%) participants, respectively. DKD was documented in 175 participants (33.7%). Compared with those without DKD, participants with DKD were more likely to be ≥ 50 years of age (53.7% vs. 43%, p = 0.02) and to have co-existing hypertension at the time of diagnosis (40.6% vs. 30.1%, p = 0.02). On multivariate analysis, self-reported hypertension comorbidity (OR 1.76 95% CI 1.24-2.48, p = 0.002) and body mass index (BMI) ≥ 30 kg/m2 (OR 0.61 95% CI 0.41-0.91, p = 0.02) were noted to independently predict DKD. CONCLUSION: In this study population, DKD was relatively common and was independently associated with self-reported hypertension comorbidity and BMI ≥ 30 kg/m2.

Being overweight worsens the relationship between urinary sodium excretion and albuminuria: the Wakuya study.

BACKGROUND/OBJECTIVES: (Micro)albuminuria (a manifestation of renal microvascular damage) is an independent predictor of mortality risk, even when the urinary albumin/creatinine ratio is ≥ 10 mg/g in the general population. Excessive sodium intake and obesity are strong predictors of cardiovascular disease. However, the effect of obesity on the relationship between sodium intake and albuminuria is not fully understood. SUBJECTS/METHODS: The purpose of the present study was to investigate the cross-sectional relationships among dietary sodium intake, obesity, and albuminuria in a general population cohort. Subjects were 928 apparently healthy adults. Body mass index was calculated using the height and body weight. Urinary sodium/creatinine and albumin/creatinine ratios were measured in spot urine samples. Estimated 24-h urinary sodium/creatinine ratio (e24UNa/Cr) was assessed using age, height, body weight, and spot urinary sodium/creatinine ratio. RESULTS: Both the body mass index and e24UNa/Cr positively correlated with the urinary albumin/creatinine ratio (both, P < 0.001), and had a synergistic effect on increasing urinary albumin/creatinine ratio independent of age, sex, mean arterial pressure, and diabetes (interaction P = 0.04). When subjects were divided into 6 groups according to the tertiles of e24UNa/Cr and body mass index < (normal-weight) or ≥ 25 (overweight), the prevalence rate of urinary albumin/creatinine ratio ≥ 10 mg/g increased with rising e24UNa/Cr and being overweight (P < 0.001). CONCLUSION: An increase in body mass index increases the positive association between urinary sodium excretion and (micro)albuminuria in the general population. Excess sodium intake may strengthen cardiovascular risk by increasing (micro)albuminuria, particularly in overweight individuals.

Albuminuria-Related Genetic Biomarkers: Replication and Predictive Evaluation in Individuals with and without Diabetes from the UK Biobank.

Increased albuminuria indicates underlying glomerular pathology and is associated with worse renal disease outcomes, especially in diabetic kidney disease. Many single nucleotide polymorphisms (SNPs), associated with albuminuria, could be potentially useful to construct polygenic risk scores (PRSs) for kidney disease. We investigated the diagnostic accuracy of SNPs, previously associated with albuminuria-related traits, on albuminuria and renal injury in the UK Biobank population, with a particular interest in diabetes. Multivariable logistic regression was used to evaluate the influence of 91 SNPs on urine albumin-to-creatinine ratio (UACR)-related traits and kidney damage (any pathology indicating renal injury), stratifying by diabetes. Weighted PRSs for microalbuminuria and UACR from previous studies were used to calculate the area under the receiver operating characteristic curve (AUROC). CUBN-rs1801239 and DDR1-rs116772905 were associated with all the UACR-derived phenotypes, in both the overall and non-diabetic cohorts, but not with kidney damage. Several SNPs demonstrated different effects in individuals with diabetes compared to those without. SNPs did not improve the AUROC over currently used clinical variables. Many SNPs are associated with UACR or renal injury, suggesting a role in kidney dysfunction, dependent on the presence of diabetes in some cases. However, individual SNPs or PRSs did not improve the diagnostic accuracy for albuminuria or renal injury compared to standard clinical variables.