Isolated microalbuminuria indicates a poor medical prognosis

Association between grip strength and albuminuria in the general United States population: NHANES 2011-2014

Background

Grip strength has been shown to be associated with chronic renal insufficiency, but the relationship between grip strength and albuminuria has not been confirmed. In this study, we used NHANES data to explore the association between grip strength and albuminuria in a US population.

Methods

In this analytical study, we utilized data sourced from the National Health and Nutrition Examination Survey (NHANES), specifically spanning the years 2011 to 2014. The dataset included 9,638 participants aged 20 years or older. After adjusting for potential confounders, multiple regression models were developed to infer the interrelationship between grip strength and albumin to creatinine ratio (ACR), and subgroup analyses were conducted.

Results

After adjusting for all covariates, ACR by 0.49 mg/g [-0.49 (95% CI: -0.93, -0.04)] for each 1 kg increase in grip strength decreased. Subgroup analysis showed that gender, age, hyperlipidemia, hypertension, diabetes mellitus, smoking, alcohol consumption and body mass index did not influence the negative correlation between grip strength and albuminuria.

Conclusion

There is a negative correlation between grip strength and albuminuria in the general U.S. population.

Association of urinary albumin-to-creatinine ratio with cardiometabolic risk markers and pre-diabetes in adults with normoglycemia, normoalbuminuria, and normotension with parental type 2 diabetes

INTRODUCTION

This is a post hoc analysis of urinary albumin-to-creatinine ratio (uACR) within the normoalbuminuric range in relation to cardiometabolic risk factors among initially normoglycemic, normotensive participants in the Pathobiology of Prediabetes in a Biracial Cohort (POP-ABC) Study.

RESEARCH DESIGN AND METHODS

308 healthy African American (AA) and European American (EA) participants in the POP-ABC Study underwent baseline assessments, including oral glucose tolerance test, anthropometry, urinary albumin-to-creatinine ratio (uACR), lipids, adipocytokines, insulin sensitivity and secretion. Participants were followed quarterly for 5.5 years (mean 2.62 years) for the primary outcome of incident pre-diabetes.

RESULTS

The cohort's mean fasting glucose was 92.1±6.90 mg/dL, 2-hour plasma glucose was 123±25.0 mg/dL, systolic blood pressure was 123±15.9 mm Hg, and diastolic blood pressure was 74±8.80 mm Hg. Baseline uACR levels (range 1-29 mg/g) were similar in AA versus EA participants (6.40 mg/g±4.80 vs 6.80±5.40 mg/g, p=0.52), higher in women than men (7.30 mg/g±5.30 vs 4.60±3.90 mg/g, p<0.0001), and showed significant associations with cardiometabolic risk factors, including age, insulin sensitivity, high-density lipoprotein cholesterol, and adiponectin levels (p=0.03-0.004). During 5.5 years of follow-up, 104 participants developed pre-diabetes and 204 maintained normoglycemia. Baseline uACR quartiles were associated with incident pre-diabetes (r=0.19, p=0.0011).

CONCLUSIONS

Baseline uACR levels were associated with cardiometabolic risk markers and incident pre-diabetes risk among adults with normoglycemia, normoalbuminuria and normotension with parental diabetes.

Longitudinal relationship between albuminuria in infancy and childhood

BACKGROUND

Mildly increased albuminuria is common in the general adult population and is a strong predictor for cardiovascular events, even in otherwise healthy individuals. The underlying pathophysiological process could be endothelial dysfunction. Previously, we reported that increased albuminuria can also be found in 2-year-olds from the general population. We hypothesized that some individuals have constitutionally higher levels of albuminuria, possibly as an expression of early or inborn endothelial dysfunction. The aim of this study is to evaluate longitudinal persistence of albuminuria from infancy into school age.

METHODS

In the population-based GECKO (Groningen Expert Center for Kids with Obesity) cohort, urine was collected from 816 children at the age of 2 years as well as 12 years (random urine and first morning void urine, respectively). We evaluated prevalence and persistence of increased albuminuria (UACR ≥ 3 mg/mmol) at the two time points.

RESULTS

The prevalence of UACR ≥ 3 mg/mmol at 2 and 12 years of age was 31.9% (95% CI 28.7-35.2) and 3.1% (95% CI 2.0-4.5), respectively. UACR < 3 mg/mmol at both 2 and 12 years of age was present in 540 children (66.2%). Only 9 children (3.5%) of the 260 children with an UACR ≥ 3 mg/mmol at 2 years had an UACR ≥ 3 mg/mmol at 12 years (p < 0.001).

CONCLUSION

Albuminuria in 2-year-olds does largely not persist until the age of 12, indicating that albuminuria at 2 years of age is not a marker for constitutional endothelial dysfunction in this cohort. A higher resolution version of the Graphical abstract is available as Supplementary information.

Time-Varying Proteinuria and the Risk of Cardiovascular Disease and Graft Failure in Kidney Transplant Recipients

Introduction: Proteinuria is recognized as an independent risk factor for cardiovascular disease in kidney transplant recipients, but previous studies have not considered the impact of changes in urine protein over time. Research Question and Design: We used time-dependent, multivariable Cox proportional hazards models in this observational cohort study of adult kidney transplant recipients to evaluate whether proteinuria measured by dipstick on random spot urine samples starting from 1-month post-transplant was associated with the risk of major adverse cardiac events and graft loss. Results: A total of 144 major adverse cardiac events, defined as acute myocardial infarction, cerebrovascular accident, revascularization, or all-cause mortality, were observed in 1106 patients over 5728.7 person-years. Any level of proteinuria greater or equal to trace resulted in a two-fold increase in the risk of major adverse cardiac events (hazard ratio 2.00 [95% confidence interval 1.41, 2.84]). This relationship was not found to be dose-dependent (hazard ratios of 2.98, 1.76, 1.63, and 1.54 for trace, 1+, 2+, and 3+ urine protein, respectively). There was an increased risk of graft failure with greater urine protein concentration (hazard ratios 2.22, 2.85, 6.41, and 19.71 for trace, 1+, 2+, and 3+, respectively). Conclusion: Urine protein is associated with major adverse cardiac events and graft loss in kidney transplant recipients. The role of interventions to reduce proteinuria on decreasing the risk of adverse cardiovascular and graft outcomes in kidney transplant recipients requires further study.

Does Microalbuminuria Predict Mortality in Pediatric Intensive Care Unit?

The aim of this study is to assess the accuracy of microalbuminuria (MA) to predict the mortality in pediatric intensive care unit (PICU). Between December 2014 and November 2015, 250 patients who were 1 month to 18 years old monitored at least 24 hours in PICU and met study criteria were included. Spot urine samples were measured for microalbuminuria. Pediatric Risk of Mortality III-24 and Pediatric Multiple Organ Dysfunction scores were calculated by using the worst parameters in first 24 hours. The collected data were analyzed with statistical methods and compared with mortality scoring systems and observed mortality. MA values were significantly higher in nonsurvivors than the average of the survivors (18 vs. 48 mg/g, p < 0.05). The receiver operating characteristics curve analysis showed that the areas under the curves for MA was 0.81 at a cut-off value of 32 mg/g, MA measured in 24 hours of admission to PICU may be able to discriminate between patients a with sensitivity of 85.2, specificity of 70.8%, positive predictive value of 31.5%, and negative predictive value of 96.8%. MA is a useful tool to predict mortality in PICU.

Microalbuminuria and cardiorenal risk: old and new evidence in different populations

Since the association of microalbuminuria (MAU) with cardiovascular (CV) risk was described, a huge number of reports have emerged. MAU is a specific integrated marker of CV risk and targets organ damage in patients with hypertension, chronic kidney disease (CKD), and diabetes and its recognition is important for identifying patients at a high or very high global CV risk. The gold standard for diagnosis is albumin measured in 24-hour urine collection (normal values of less than 30 mg/day, MAU of 30 to 300 mg/day, macroalbuminuria of more than 300 mg/day) or, more practically, the determination of urinary albumin-to-creatinine ratio in a urine morning sample (30 to 300 mg/g). MAU screening is mandatory in individuals at risk of developing or presenting elevated global CV risk. Evidence has shown that intensive treatment could turn MAU into normoalbuminuria. Intensive treatment with the administration of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, in combination with other anti-hypertensive drugs and drugs covering other aspects of CV risk, such as mineralocorticoid receptor antagonists, new anti-diabetic drugs, and statins, can diminish the risk accompanying albuminuria in hypertensive patients with or without CKD and diabetes.

Role of Microalbuminuria in Predicting Cardiovascular Mortality in Individuals With Subclinical Hypothyroidism

PURPOSE

Studies suggest that subclinical hypothyroidism (SCH) is related to cardiovascular mortality (CVM). We explored the role of microalbuminuria (MIA) as a predictor of long-term CVM in population with and without SCH with normal kidney function.

MATERIALS AND METHODS

We examined the National Health and Nutrition Education Survey - III database (n = 6,812). Individuals younger than 40 years, thyroid-stimulating hormone levels ≥20 and ≤0.35mIU/L, estimated glomerular filtration rate <60mL/minute/1.73m² and urine albumin-to-creatinine ratio of >250mg/g in men and >355mg/g in women were excluded. SCH was defined as thyroid-stimulating hormone levels between 5 and 19.99mIU/L and serum T4 levels between 5 and 12µg/dL. MIA was defined as urine albumin-to-creatinine ratio of 17-250mg/g in men and 25-355mg/g in women. Patients were categorized into the following 4 groups: (1) no SCH or MIA, (2) MIA, but no SCH, (3) SCH, but no MIA and (4) both SCH and MIA.

RESULTS

Prevalence of MIA in the subclinical hypothyroid cohort was 21% compared to 16.4% in those without SCH (P = 0.03). SCH was a significant independent predictor of MIA (n = 6,812), after adjusting for traditional risk factors (unadjusted odds ratio = 1.75; 95% CI: 1.24-2.48; P = 0.002 and adjusted odds ratio = 1.83; 95% CI: 1.2-2.79; P = 0.006). MIA was a significant independent predictor of long-term all-cause (adjusted hazard ratio = 1.7, 95% CI: 1.24-2.33) and CVM (adjusted hazard ratio = 1.72, 95% CI: 1.07-2.76) in subclinical hypothyroid individuals.

CONCLUSIONS

In a cohort of subclinical hypothyroid individuals, the presence of MIA predicts increased risk of CVM as compared to nonmicroalbuminurics with SCH. Further randomized trials are needed to assess the benefits of treating microalbuminuric subclinical hypothyroid individuals and impact on CVM.

Association between Overall Lifestyle Changes and the Incidence of Proteinuria: A Population-based, Cohort Study

Objective This study aimed to examine the association between the changes in an overall healthy lifestyle, as quantified by the number of unhealthy lifestyle factors and obesity status, and the incidence of proteinuria in the general Japanese population. Methods A retrospective cohort study was conducted among 99,404 (men, 36.9%) participants aged from 40-74 years of age who underwent two health check-ups with a 1-year interval in Japan between 2008 and 2009. Any participants with chronic kidney disease at baseline were excluded. The smoking status, body mass index, physical activity, alcohol consumption, and healthy eating habits were combined into a simple overall healthy lifestyle score ranging from 0 to 5. The changes in overall healthy lifestyle scores from baseline (range, -5 to +5) and the incidence of proteinuria, defined by a dipstick urinalysis (score ≥1+), were assessed at the second check-up. A logistic regression analysis was used to examine the association between the changes in overall healthy lifestyle scores and the incidence of proteinuria. Results After one year of follow-up, 3.9% of men and 2.4% of women developed proteinuria. Each increase (or decrease) in the changes in overall healthy lifestyle scores was associated with a reduced (or increased) risk of proteinuria in both men (odds ratio (OR) 0.87; 95% confidence interval (CI), 0.81-0.94) and women (OR 0.87; 95%CI, 0.80-0.94) after adjusting for age, baseline lifestyle scores, hypertension, diabetes mellitus, and hypercholesterolemia. Stratified analyses based on age, the presence or absence of hypertension, or diabetes mellitus revealed similar results. Conclusion Overall lifestyle changes, even within a year, were found to influence the incidence of proteinuria.

Impact of glucose load in an oral glucose tolerance test on urinary albumin excretion varies with 2-h glucose levels

BACKGROUND

The aim of the present study was to investigate whether an oral glucose load can induce an increase in urinary albumin excretion (UAE).

METHODS

One hundred and thirty subjects without macroalbuminuria or increased fasting serum glucose (≥7.0 mmol/L) were included in the study. At 0600 hours, subjects were asked to empty their bladder and drink 300 mL water. At 0800 hours, venous blood and 2-h urine were collected for fasting examination. Subjects were then asked to drink 300 mL solution containing 75 g glucose and, at 1000 hours, samples were collected again for post-challenge examination. Concentrations of serum glucose, urinary glucose, albumin, N-acetyl-β-D-glucosaminidase and retinol-binding protein were measured.

RESULTS

Based on the results of the oral glucose tolerance test, subjects were divided into three groups: (i) normal glucose tolerance (NGT; n = 55); (ii) impaired glucose tolerance (IGT; n = 39); and (iii) newly diagnosed diabetes mellitus (NDM; n = 36). In the NDM group, post-challenge urinary excretion of glucose and albumin was 14- and 1.6-fold greater than fasting values, respectively. In the IGT and NGT groups, although post-challenge urinary glucose excretion was 2.6- and 1.6-fold greater than fasting values, UAE did not increase. There was a positive correlation between post-challenge serum glucose and the UAE rate (UAER; r = 0.24, P < 0.01) and the UAER increment (ΔUAER; r = 0.19, P < 0.05), as well as between the serum glucose increment and post-challenge UAER (r = 0.23, P < 0.01) and ΔUAER (r = 0.18, P < 0.05). Post-challenge serum glucose levels were independently correlated with logarithmically converted post-challenge UAER (β = 0.322, P = 0.008).

CONCLUSIONS

Oral glucose load can induce a significant increase in UAE in NDM subjects. The main mechanism may be glomerular hyperfiltration.

Association of Renal Resistive Index, Renal Pulsatility Index, Systemic Hypertension, and Albuminuria with Survival in Dogs with Pituitary-Dependent Hyperadrenocorticism

An increased renal resistive index (RI) and albuminuria are markers of target organ damage secondary to systemic hypertension. This study evaluated associations between systemic blood pressure (SBP), renal RI, pulsatility index (PI), and albuminuria in dogs with pituitary-dependent hyperadrenocorticism (PDH). Predictors of overall mortality were investigated. Twenty client-owned dogs with PDH and 20 clinically healthy client-owned dogs as matched controls were included. Incidence rates of systemic hypertension (SBP ≥ 160 mmHg), albuminuria, and increased renal RI (≥ 0.70) and PI (≥ 1.45) in the control group were 5%, 0%, 5%, and 0%, respectively, compared to 35%, 40%, 50%, and 35%, respectively, in the PDH group (P = 0.001, P < 0.001, P < 0.001, and P = 0.001, resp.). No association between systemic hypertension, renal RI, renal PI, and albuminuria was observed. PDH was the only predictor of albuminuria and increased renal RI. Survival was not affected by increased renal PI, systemic hypertension, or albuminuria. Increased renal RI (≥ 0.70) was the only predictor of overall mortality in dogs with PDH.

Vitamin D and chronic kidney disease-mineral bone disease (CKD-MBD)

Chronic kidney disease (CKD) is a modern day epidemic and has significant morbidity and mortality implications. Mineral and bone disorders are common in CKD and are now collectively referred to as CKD- mineral and bone disorder (MBD). These abnormalities begin to appear even in early stages of CKD and contribute to the pathogenesis of renal osteodystrophy. Alteration in vitamin D metabolism is one of the key features of CKD-MBD that has major clinical and research implications. This review focuses on biology, epidemiology and management aspects of these alterations in vitamin D metabolism as they relate to skeletal aspects of CKD-MBD in adult humans.

Prevalence of and factors associated with albuminuria in the Korean adult population: the 2011 Korea National Health and Nutrition Examination Survey

BACKGROUND

Microalbuminuria is associated with increased risk of renal disease and cardiovascular diseases even in non-diabetic subjects. High incidence rates of microalbuminuria have been found in a number of population-based studies. However, the prevalence and risk factors associated with microalbuminuria in the general population in Korea are unclear.

OBJECTIVES

The present study was performed to estimate the prevalence of microalbuminuria and investigate the associated risk factors in the general adult population using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-2) data from 2011.

METHODS

A total of 5,202 participants (mean age, 45.6 years; men, 2,337; women, 2,865) were included in the analysis. Microalbuminuria was evaluated in participants of KNHANES V-2 based on the urine albumin-creatinine ratio. Estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease study equation.

RESULTS

The weighted prevalence of microalbuminuria was 5.2% (95% CI, 4.4-6.1) in the general population. The prevalence of albuminuria is increased with age. After adjustment for age and sex, the presence of albuminuria was associated with increased waist circumference, systolic and diastolic blood pressure, aspartate aminotransferase, triglyceride, fasting plasma glucose, and the presence of hypertension and diabetes. In logistic regression analyses, older age, female sex, diabetes, hypertension, and serum aspartate aminotransferase were independently associated with the presence of albuminuria.

CONCLUSION

The prevalence of microalbuminuria was found to be 5.2%, and conventional risk factors for cardiovascular diseases are closely related to the presence of microalbuminuria in Korea. Microalbuminuria may be a useful marker to identify individuals with increased risk of cardiovascular disease.