Microalbuminuria: marker or maker of cardiovascular disease

Kidney damage predictors in children with metabolically healthy and metabolically unhealthy obesity phenotype

BACKGROUND

Obesity and kidney damage have been closely linked in adults, but little is still known in childhood.

OBJECTIVE

To identify predictors of kidney damage in children with metabolically healthy (MHO) and metabolically unhealthy (MUO) obesity phenotypes.

METHODS

We retrospectively examined 396 children with obesity (mean age 10.72 ± 2.71 years, body mass index-standard deviation score, BMI-SDS, 2.23 ± 0.57) stratified according to metabolic phenotypes. Kidney damage was defined as the presence of reduced estimated glomerular filtration rate (eGFR < 90 mL/min/1.73m2) and/or albuminuria (≥ 30 mg/g urinary creatinine).

RESULTS

Kidney damage was found in 20.9% of the study population. Children with kidney damage had higher BMI-SDS, homeostasis model assessment of insulin resistance (HOMA-IR), and inflammation markers levels and increased prevalence of non-alcoholic fatty liver disease (NAFLD) than those without kidney damage (all p < 0.005). MUO and MHO subjects had respectively an odds ratio (OR) to show kidney damage of of 1.92 (95%CI:1.22-3.01; p = 0.005) and 1.05 (95%CI:1.00-1.09; p = 0.028) after adjustments. Moreover, we found that only HOMA-IR was closely associated to kidney damage in MUO group (OR = 2.07;95%CI:1.20-3.57; p = 0.007), while HOMA-IR (OR = 1.15;95%CI:1.02-1.29; p = 0.011) and uric acid (OR = 1.15;95% CI:1.02-1.30; p = 0.010) were the only significant risk factors for kidney damage in MHO group.

CONCLUSION

An increased risk of kidney damage has been observed in children with obesity and in particular in those with MUO phenotype. As their role on kidney function, HOMA-IR should be monitored in MUO children and both HOMA-IR and uric acid in MHO children.

Association of high-normal albuminuria and vascular aging: Hanzhong adolescent hypertension study

Normoalbuminuria has recently been associated with increased cardiovascular risk, and vascular aging is proposed as the early manifestation of cardiovascular disease. Here, the authors aimed to examine the association of high-normal albuminuria and vascular aging in a Chinese cohort. From our previously established cohort, 1942 participants with estimated glomerular filtration rate ≥60 mL/min/1.73 m2 or urinary albumin-creatinine ratio (UACR) <30 mg/g were enrolled. Brachial-ankle pulse wave velocity (baPWV) ≥1400 cm/s and/or carotid intima-media thickness (CIMT) ≥0.9 mm were used as indicators of vascular aging. Multivariate regression and receiving operating characteristic curve analysis were performed to examine the relationship between continuous and categorical UACR with vascular aging. We found an average UACR value of 8.08 (5.45-12.52) mg/g in this study. BaPWV and CIMT demonstrated positive correlations with lg-UACR (p < .05). High-normal albuminuria (10-29 mg/g) was significantly associated with the presence of vascular aging after adjusting for multiple cardiovascular confounders (OR = 1.540, 95% CI = 1.203-1.972, p = .001). In addition, a lg-UACR cutoff point of 0.918 lg(mg/g) (equal to UACR of 8.285 mg/g) was significantly associated with the presence of vascular aging and its components for all participants and those without hypertension or diabetes and without medication (p < .05). Briefly, high-normal albuminuria was significantly associated with vascular aging in this sample of Chinese adults. These findings implied the warning of elevated UACR even within normal range in clinical practice and the importance of UACR screening in normoalbuminuria for early detection and prevention of cardiovascular disease in otherwise healthy participants.

Microvascular reactivity using laser Doppler measurement in type 2 diabetes with subclinical atherosclerosis

Microangiopathy should be noted in diabetes with subclinical vascular diseases. Little is known about whether various surrogate markers of systemic arterial trees exacerbate simultaneously in preclinical atherosclerosis. To clarify the association of skin microvascular reactivity with arterial stiffness is essential to elucidating early atherosclerotic changes. The post-occlusive reactive hyperemia of skin microcirculation was evaluated in 27 control and 65 type 2 diabetic subjects, including 31 microalbuminuria (MAU) and 34 normoalbuminuria (NAU) patients. The laser Doppler skin perfusion signals were transformed into three frequency intervals for the investigation of endothelial, neurogenic, and myogenic effects on basal and reactive flow motion changes. The analysis of spectral intensity and distribution provided insight into potential significance of microvascular regulation in subclinical atherosclerotic diseases. Systemic arterial stiffness was studied by the brachial ankle pulse wave velocity (baPWV). Following occlusive ischemia, the percent change of endothelial flow motion was lower in MAU than in NAU and control groups. The MAU group revealed a relative increase in myogenic activity and a decrease in endothelial activity in normalized spectra. The baPWV showed more significant associations with reactive endothelial change (r = - 0.48, P < 0.01) and normalized myogenic value (r = - 0.37, P < 0.05) than diabetes duration and HbA1c. By multivariate regression analysis, only endothelial vasomotor changes independently contributed to the decreased baPWV (OR 3.47, 95% CI 1.63-7.42, P < 0.05). Impaired microcirculatory control is associated with increased arterial stiffness in preclinical atherosclerosis. To identify the early manifestations is necessary for at-risk patients to prevent from further vascular damage.

Impact of Albuminuria on the Prognosis After Transcatheter Aortic Valve Implantation

The impact of preoperative albuminuria on the prognosis after transcatheter aortic valve implantation (TAVI) has not been studied. A total of 228 patients who underwent TAVI for severe aortic stenosis (AS) and for whom preoperative urinary data was available were retrospectively investigated. Patients were divided into two groups according to the urinary albumin-to-creatinine ratio (ACR): high (ACR≥ 30 mg/g) and low (ACR<30 mg/g). The urinary total protein-to-creatinine ratio (PCR) and dipstick proteinuria were also evaluated. The primary outcome was the composite outcome of all-cause death and readmission for heart failure. In total, 117 patients had a high ACR and 111 patients had a low ACR. During the median follow-up period of 467 days, patients with a high ACR had a higher incidence of the primary outcome than those with a low ACR (p<0.001). Patients with a high PCR or positive dipstick proteinuria were also at a higher risk for the primary outcome (p<0.001 and p=0.008, respectively). Multivariable Cox proportional hazards analysis showed a high ACR was independently associated with a primary outcome (hazard ratio, 4.98; 95% confidence interval, 1.84-13.49; p=0.002). In conclusion, preoperative albuminuria is an independent predictor of cardiac events in patients with severe AS undergoing TAVI.

Decreased renal function is associated with incident dementia: An IMRD-THIN retrospective cohort study in the UK

INTRODUCTION

Decreased renal function is a potential risk factor for dementia.

METHODS

This retrospective cohort study of 2.8 million adults aged ≥50 years used the IMRD-THIN database, representative of UK primary care, from January 1, 1995 to February 24, 2020. The associations between estimated glomerular filtration rate (eGFR) and urine albumin creatinine ratio (ACR) with incident all-cause dementia were analyzed using Cox regression.

RESULTS

In the eGFR cohort (n = 2,797,384), worsening renal dysfunction was associated with increased hazard of all-cause dementia, with greatest hazard at eGFR 15-30 ml/min/1.73min² (hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.19-1.33). In the ACR cohort (n = 641,912), the hazard of dementia increased from ACR 3-30 mg/mmol (HR 1.13, 95% CI 1.10-1.15) to ACR > 30 mg/mmol (HR 1.25, 95% CI 1.18-1.33).

DISCUSSION

Worsening eGFR and albuminuria have graded associations with the risk of dementia, which may have significant implications for the care of patients with kidney disease.

Association of Dietary Fish and n-3 Unsaturated Fatty Acid Consumption with Diabetic Nephropathy from a District Hospital in Northern Taiwan

Nephropathy caused by diabetes mellitus (DM) is the main cause of end-stage renal disease (ESRD). To understand the association of dietary intake with renal function indicators among patients with diabetic nephropathy (DN), this cross-sectional study was conducted at the dietetic consultation clinic of the Taoyuan Armed Forces General Hospital in Taiwan. In total, 317 participants were recruited for this study. Patients with diabetes who had a urinary albumin–creatinine ratio (UACR) of ≥30 mg/g were defined as having DN. The anthropometric characteristics, blood biochemistry, and renal function of the participants were assessed. Furthermore, a semiquantitative food frequency questionnaire (SQFFQ) was administered to investigate the dietary intake of the participants in the DM and DN groups. The result showed that participants in the DN group were older, had longer diabetes duration and poorer glycemic control and renal function than those in the DM group. Logistic regression models revealed that intake of high-fat marine fishes had the lowest odds ratio (OR) for DN risk compared with other fishes (OR: 0.868; 95% CI: 0.781–0.965, p = 0.009). Shellfish, soybean products, and skim milk also provided better protective effects to decrease the risk of DN. A further analysis of polyunsaturated fatty acids revealed that Σn-3 PUFAs significantly reduced DN risk, while Σn-6 PUFAs did not, especially EPA (OR: 0.821; 95% CI: 0.688–0.979, p = 0.029) and DHA (OR: 0.903; 95% CI: 0.823–0.992, p = 0.033) regardless of whether the variables were adjusted, including diabetes duration, age, and HbA1c. Our findings suggest that a diet that incorporates high-fat fish, shellfish, soybean products, and a lower Σn-6/Σn-3 ratio can mitigate DN risk.

High Normal Urinary Albumin-Creatinine Ratio Is Associated With Hypertension, Type 2 Diabetes Mellitus, HTN With T2DM, Dyslipidemia, and Cardiovascular Diseases in the Chinese Population: A Report From the REACTION Study

Background

Albuminuria has been widely considered a risk factor for cardiovascular diseases (CVDs), which is associated with hypertension (HTN), type 2 diabetes mellitus (T2DM), HTN with T2DM, and dyslipidemia. However, the associations between albuminuria and HTN, T2DM, HTN with T2DM, dyslipidemia, and CVDs are still unclear. Thus, this study aimed to explore the association of albuminuria thoroughly, especially within the normal range, with the abovementioned diseases in the Chinese population.

Methods

This study included 40,188 participants aged over 40 years from seven centers across China. Urinary albumin-creatinine ratio (UACR) was firstly divided into the ≥30-mg/g group, indicating kidney damage, and <30-mg/g group. Furthermore, UACR was divided into five groups: the <20%, 20%-39%, 40%-59%, 60%-79%, and ≥80% groups, according to the quintile division of participants within the normal range. Propensity score matching was used to reduce bias, and multiple logistic regression models were conducted to examine the association between UACR and HTN, T2DM, HTN with T2DM, dyslipidemia, and CVDs.

Results

Multivariable regression analysis revealed that UACR, even within the normal range, is significantly associated with HTN, T2DM, HTN with T2DM, dyslipidemia, and CVDs, and the association between UACR and HTN with T2DM was the most significant in model 3 even after adjusting for confounding factors (HTN: OR = 1.56 (95% CI = 1.45-1.68), p < 0.0001; T2DM: OR = 1.78 (95% CI = 1.60-1.97), p < 0.0001; HTN with T2DM: OR = 1.76 (95% CI = 1.59-1.95), p < 0.0001; dyslipidemia: OR = 1.08 (95% CI = 1.01-1.14), p = 0.0146; CVDs: OR = 1.12 (95% CI = 1.00-1.25), p = 0.0475). In the stratified analysis, high normal UACR was significantly associated with HTN, T2DM, HTN with T2DM, and dyslipidemia in subgroups.

Conclusions

In summary, we observe a higher prevalence of HTN, T2DM, HTN with T2DM, dyslipidemia, and CVDs in abnormal UACR and reveal a significant association of UACR, even within the normal range, with HTN, T2DM, HTN with T2DM, dyslipidemia, and CVDs.

Correlation between microalbuminuria and atherosclerotic intracranial and extracranial arterial stenosis in patients with cerebral infarction

BACKGROUND AND AIMS

Microalbuminuria (MAU) reflects the generalized vascular endothelial dysfunction. Whether MAU has correlation with atherosclerotic intracranial and extracranial arterial stenosis in cerebral infarction patients is not known and is explored in the present investigation.

METHODS

We enrolled 255 cerebral infarction patients hospitalized at the department of neurology. All patients underwent digital subtraction angiography (DSA) to evaluate the severity and distribution of intracranial and extracranial arterial stenosis. MAU was expressed as the urine albumin-to-creatinine ratio (UACR). We collected basic information, medical history reviews and laboratory results of each participant. The multivariate logistic regression analysis was utilized to analyze the risk factors for severity and distribution of cerebral arterial stenosis.

RESULTS

The prevalence of MAU in patients with cerebral infarction was 39.2%, patients with MAU had older age, lower blood uric acid, higher systolic blood pressure (SBP), higher prevalence of hypertension and diabetes (p < 0.05) and higher incidence of atherosclerotic intracranial and extracranial arterial stenosis (χ2 = 5.900, p = 0.015). In multiple logistic regression analysis for intracranial and extracranial arterial stenosis more than 50% or occlusion groups, UACR (OR 1.088 95%CI 1.012-1.170p = 0.022), male (OR 2.196 95%CI 1.085-4.442p = 0.029) as well as SBP (OR 5.870 95%CI 1.026-1.048p = 0.015) showed statistical significance. But UACR had no correlation with the distribution of intracranial and extracranial artery stenosis after adjusting for all potential confounders.

CONCLUSIONS

Microalbuminuria was an independent risk factor for intracranial and extracranial arterial stenosis more than 50% or occlusion.

Association of the Atherogenic Index of Plasma with C-Reactive Protein and Urinary Albumin Excretion in a Normotensive Nondiabetic Population

Background: The atherogenic index of plasma (AIP) is an indicator of atherogenic dyslipidemia and is significantly associated with the development of atherosclerotic cardiovascular disease. Previous studies showing the association of AIP with C-reactive protein (CRP) and microalbuminuria included hypertensive and diabetic patients. We aimed to determine the association of AIP with CRP and albuminuria in a normotensive and nondiabetic population. Methods: The study was conducted retrospectively. Two hundred thirty-three individuals without hypertension, diabetes, cardiovascular disease, malignancy, systemic inflammatory disease, nephrological disease, and active infection were determined and included in the study. Urinary albumin excretion was calculated from the albumin-creatinine ratio in fresh spot urine [urinary albumin-creatinine ratio (UACR)]. AIP risk groups were compared in terms of clinical and laboratory findings, and the correlation between AIP and CRP and UACR was evaluated. Results: A total of 233 people, with a mean age of 45.4 years and 139 (69.7%) of whom were male, were included in the study. One hundred thirty-eight (59.2%) individuals were found to be in the low-risk group, 29 (12.5%) in the medium-risk group, and 66 (28.3%) in the high-risk group, according to the AIP value. CRP and UACR were not different between the AIP risk groups (P: 0.141 and 0.441, respectively). A mild correlation was found between AIP and CRP (r: 0.192; P: 0.003), but no correlation was found between AIP and UACR (r: 0.086; P: 0.193). The stepwise linear regression analysis with model adjusted for possible confounders and AIP revealed that only body mass index was a significant predictor of CRP (β: 0.308; P < 0.001), while only systolic blood pressure was a significant predictor of UACR (β: 0.19; P: 0.004), but AIP was not. Conclusions: AIP was not associated with CRP and UACR in normotensive and nondiabetic individuals. This finding suggests that the relationship found in previous studies is related to the presence of hypertension or diabetes rather than the AIP.

Urinary levels of pro-fibrotic transglutaminase 2 (TG2) may help predict progression of chronic kidney disease

Renal clinical chemistry only detects kidney dysfunction after considerable damage has occurred and is imperfect in predicting long term outcomes. Consequently, more sensitive markers of early damage and better predictors of progression are being urgently sought, to better support clinical decisions and support shorter clinical trials. Transglutaminase 2 (TG2) is strongly implicated in the fibrotic remodeling that drives chronic kidney disease (CKD). We hypothesized that urinary TG2 and its ε-(γ-glutamyl)-lysine crosslink product could be useful biomarkers of kidney fibrosis and progression. Animal models: a rat 4-month 5/6th subtotal nephrectomy model of CKD and a rat 8-month streptozotocin model of diabetic kidney disease had 24-hour collection of urine, made using a metabolic cage, at regular periods throughout disease development. Patients: Urine samples from patients with CKD (n = 290) and healthy volunteers (n = 33) were collected prospectively, and progression tracked for 3 years. An estimated glomerular filtration rate (eGFR) loss of 2–5 mL/min/year was considered progressive, with rapid progression defined as > 5 mL/min/year. Assays: TG2 was measured in human and rat urine samples by enzyme-linked immunosorbent assay (ELISA) and ε-(γ-glutamyl)-lysine by exhaustive proteolytic digestion and amino acid analysis. Urinary TG2 and ε-(γ-glutamyl)-lysine increased with the development of fibrosis in both animal model systems. Urinary TG2 was 41-fold higher in patients with CKD than HVs, with levels elevated 17-fold by CKD stage 2. The urinary TG2:creatinine ratio (UTCR) was 9 ng/mmol in HV compared with 114 ng/mmol in non-progressive CKD, 1244 ng/mmol in progressive CKD and 1898 ng/mmol in rapidly progressive CKD. Both urinary TG2 and ε-(γ-glutamyl)-lysine were significantly associated with speed of progression in univariate logistic regression models. In a multivariate model adjusted for urinary TG2, ε-(γ-glutamyl)-lysine, age, sex, urinary albumin:creatinine ratio (UACR), urinary protein:creatinine ratio (UPCR), and CKD stage, only TG2 remained statistically significant. Receiver operating characteristic (ROC) curve analysis determined an 86.4% accuracy of prediction of progression for UTCR compared with 73.5% for UACR. Urinary TG2 and ε-(γ-glutamyl)-lysine are increased in CKD. In this pilot investigation, UTCR was a better predictor of progression in patients with CKD than UACR. Larger studies are now warranted to fully evaluate UTCR value in predicting patient outcomes.

Impact of lisinopril on cardiometabolic risk factors in men with hypertension and early-onset androgenetic alopecia: a pilot study

ABSTRACT

Women with polycystic ovary syndrome are at high cardiometabolic risk. Early-onset male-pattern baldness is considered the phenotypic equivalent of polycystic ovary syndrome in men. The aim of the present study was to assess whether early-onset androgenetic alopecia modifies cardiometabolic effects of lisinopril in men with arterial hypertension. The study population consisted of 62 young men with grade 1 hypertension, 31 of whom were diagnosed with early-onset male-pattern baldness (group A). Thirty-one blood pressure-matched men with normal hair growth (group B) served as a control group. All participants were treated with lisinopril (10-40 mg daily). Blood pressure, glucose homeostasis markers, urinary albumin-to-creatinine ratio (UACR), as well as plasma levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, total and calculated free testosterone, dehydroepiandrosterone-sulfate and estradiol were assessed before lisinopril treatment and six months later. At baseline, levels of all cardiometabolic risk factors were higher in group A than group B. Although lisinopril reduced systolic and diastolic blood pressure, UACR, hsCRP and fibrinogen in both study groups, these effects were stronger in group B than in group A. Only in group B, the drug decreased levels of uric acid and homocysteine, as well as improved insulin sensitivity. The impact of lisinopril on uric acid, hsCRP, fibrinogen, homocysteine and UACR correlated weakly with its hypotensive properties, androgen levels and insulin sensitivity. The obtained results suggest that cardiometabolic effects of lisinopril in men are less pronounced in case of coexisting early-onset androgenetic alopecia.

Association Between Neck Circumference and Microalbuminuria in Community Residents

OBJECTIVE

Neck circumference (NC) represents the subcutaneous fat deposition in the neck and is an effective indicator for evaluating metabolic disorders, such as metabolic syndrome, subclinical atherosclerosis, and non-alcoholic fatty liver disease. Microalbuminuria (MAU) is regarded as a potential sign of systemic endothelial dysfunction and microvascular abnormalities. The aim of this study was to elucidate the association of NC with urine albumin-to-creatinine ratio (UACR) and MAU.

METHODS

A total of 1882 Shanghai community residents were enrolled (816 men and 1066 women), with age ranging from 40 to 80 years. Anthropometric parameters, including NC, and biochemical indices were measured. MAU was determined if 30 mg/g ≤ UACR < 300 mg/g. An elevated NC was defined as NC ≥ 38.5 cm for men and NC ≥ 34.5 cm for women.

RESULTS

Individuals with an elevated NC had significantly higher prevalence of MAU and UACR values than those with normal NC in both men and women (all P < 0.05). The logistic regression analysis showed that there were significant and positive associations between elevated NC and the increasing risk of MAU after adjusting for lipid profile and glycemic indices (P = 0.007 for men and P = 0.009 for women). After further adjusting for blood pressure, elevated NC caused an 69.3% additional risk of MAU in men (P = 0.037) and the positive correlation in women disappeared (P = 0.131).

CONCLUSION

There was an independent and positive association between elevated NC and the risk of MAU in men in the Chinese community population.

CHINESE CLINICAL TRIAL REGISTRY WWWCHICTRORGCN REGISTRATION NUMBER

ChiCTR1900024011.

Urinary albumin-to-creatinine ratio within normal range and all-cause or cardiovascular mortality among U.S. adults enrolled in the NHANES during 1999-2015

PURPOSE

Urinary albumin-to-creatinine ratio (UACR) is one of the important diagnostic markers of chronic kidney disease. We aimed to investigate the association between UACR within normal range and cardiovascular or all-cause mortality.

METHODS

This study included a nationally representative sample of 31,413 U.S. adults aged greater than or equal to 20 years enrolled in the National Health and Nutrition Examination Survey 1999-2014. Mortality was ascertained through 2015. We used multivariable Cox proportional models to investigate the association of UACR with all-cause and cardiovascular mortality. Stratum-specific analyses were conducted by age, sex, race, education status, and comorbidities (e.g., hypertension, diabetes, cardiovascular disease, and chronic kidney disease).

RESULTS

Over a median follow-up of 7.6 years, 2854 all-cause deaths and 454 cardiovascular deaths were identified. Higher UACR (per 10 mg/g) was associated with increased risk of all-cause mortality (adjusted hazard ratio = 1.29, 95% confidence interval = 1.22-1.37) and cardiovascular mortality (adjusted hazard ratio = 1.34, 95% confidence interval = 1.17-1.55). The association was larger among women for both all-cause and cardiovascular mortality, and among younger and highly educated participants only for all-cause mortality. The association did not differ by the presence of comorbidities.

CONCLUSIONS

Elevated UACR within normal range was associated with higher all-cause and cardiovascular mortality risk across almost all subgroups including participants without comorbidities. Our findings suggest the importance of the early detection of albuminuria and careful evaluation of UACR even within normal range to reduce mortality risk.

Cardiometabolic risk factors in women with non-classic congenital adrenal hyperplasia

Background: No previous study has investigated cardiometabolic risk factors in untreated patients with congenital adrenal hyperplasia (CAH).Methods: The study population consisted of 14 premenopausal women with previously untreated non-classic congenital adrenal hyperplasia (NC-CAH) and 20 matched healthy women. Apart from 17-hydroxyprogesterone and androgen levels, the outcomes of interest were glucose homeostasis markers, plasma lipids, plasma levels of uric acid, C-reactive protein, fibrinogen, homocysteine and 25-hydroxyvitamin D, as well as urinary albumin-to-creatinine ratio (UACR).Results: As expected, women with NC-CAH were characterised by higher levels of 17-hydroxyprogesterone and were more insulin-resistant than control women. The mean values of C-reactive protein, fibrinogen, homocysteine and UACR were higher while 25-hydroxyvitamin D levels were lower in subjects with NC-CAH. The investigated cardiometabolic risk factors correlated with androgen levels and insulin sensitivity.Conclusions: The obtained results suggest that the occurrence of NC-CAH in premenopausal women may increase cardiometabolic risk.

Serum leptin levels are positively associated with aortic stiffness in patients with chronic kidney disease stage 3-5

Leptin potentially exerts atherogenic effects.This study evaluated the relationship between serum leptin levels and aortic stiffness in patients with stage 3-5 chronic kidney disease (CKD). Totally 205 participants were enrolled. Fasting blood sample were checked and serum leptin were measured by enzyme immunoassay. Aortic stiffness was measured as the carotid-femoral pulse wave velocity (cfPWV). 73 (35.6%) of 205 patients showed cfPWV >10 m/s were defined as aortic stiffness group. Compared with the remaining patients, the aortic stiffness group had high prevalence of diabetes mellitus, older age, higher waist circumference, body fat mass, systolic blood pressure, fasting glucose, and higher serum leptin level. In multivariable logistic regression analysis the independent predictors of cfPWV >10 m/s included leptin levels (odds ratio [OR]: 1.061, 95% confidence interval [CI]: 1.027-1.095, P < 0.001), age (OR: 1.064, 95% CI: 1.033-1.096, P< 0.001), and systolic blood pressure (OR: 1.021, 95% CI: 1.006-1.037, P = 0.006). Multivariable forward stepwise linear regression analysisshowed a positive association between log-transformed leptin levels and log-cfPWV (β = 0.192, adjusted R² change = 0.042, P = 0.001). Thus, aortic stiffness is positively correlated with serum leptin levels in patients with stage 3-5 CKD.Abbreviations: BUN, blood urea nitrogen; cfPWV, carotid-femoral pulse wave velocity; CI, confidence interval; CKD, chronic kidney disease; Cre, creatinine; DBP, diastolic blood pressure; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; LDL-C, low-density lipoprotein cholesterol; OR, odds ratio; SBP, systolic blood pressure; TCH, total cholesterol; TG, triglycerides.

Associations Between Day-by-Day Home Blood Pressure Variability and Renal Function and Albuminuria in Patients With and Without Diabetes

BACKGROUND

The phenotype of diabetic kidney disease represents a lower estimated glomerular filtration rate (eGFR) and albuminuria. We investigated the association between day-by-day home blood pressure (BP) variability and the eGFR in subjects with diabetes and compared this association with that in subjects without diabetes. We then attempted to determine whether the association is present in albuminuria.

METHODS

We analyzed 4,231 patients with risk factors of cardiovascular disease (24.4% with diabetes) from the J-HOP (Japan Morning Surge-Home Blood Pressure) study. Home BP was measured in the morning and evening for 14 days. We calculated the SD, coefficient of variation, average real variability (ARV), and variation independent of the mean of the subjects' morning and evening home systolic BP (SBP) as the indexes of day-by-day home BP variability.

RESULTS

A multiple linear regression analysis adjusted for covariates showed both average morning and evening SBP were associated with the log-transformed urine albumin-to-creatinine ratio (UACR) with and without diabetes (all P < 0.05), but not with the eGFR except for an association of average evening SBP in the no-diabetes group. None of the indexes of day-by-day morning and evening home SBP variability were associated with the log-transformed UACR except for the association between the ARV of home morning SBP in the diabetes group. All of the indexes of day-by-day morning and evening home SBP variability were associated with the eGFR only in the diabetes group (all P < 0.05).

CONCLUSIONS

The association between increased day-by-day home BP variability and impaired renal function was unique in diabetes.

Urinary albumin-to-creatinine ratio is inversely related to nitric oxide synthesis in young black adults: the African-PREDICT study

Hypertension is common in black populations and is known to be associated with low nitric oxide (NO) bioavailability. We compared plasma and urinary NO-related markers and plasma creatine kinase (CK) levels between young healthy black and white adults along with the associations of these markers with the urinary albumin-to-creatinine ratio (uACR), which is a surrogate marker of endothelial and kidney function. We included 1105 participants (20-30 years). We measured the uACR, plasma CK, plasma and urinary arginine, homoarginine, asymmetric (ADMA) and symmetric dimethylarginine (SDMA), urinary ornithine/citrulline, nitrate and nitrite, and malondialdehyde (MDA). In addition, the urinary nitrate-to-nitrite ratio (U_NOxR) was calculated and used as a measure of circulating NO bioavailability. The uACR was comparable between the groups, yet the black group had lower urinary nitrate (by -15%) and U_NOxR values (by -18%) (both p ≤ 0.001), higher plasma (by +9.6%) and urinary (by +5.9%) arginine (both p ≤ 0.004), higher plasma (by +13%) and urinary (by +3.7%) ADMA (both p ≤ 0.033), and higher CK (by +9.5%) and MDA (by +19%) (both p < 0.001) compared with white adults. Plasma and urinary homoarginine were similar between the groups. In the multiple regression analysis, we confirmed the inverse associations of the uACR with both plasma (adj. R² = 0.066; β = -0.209; p = 0.005) and urinary (adj. R² = 0.066; β = -0.149; p = 0.010) homoarginine and with the U_NOxR (adj. R² = 0.060; β = -0.122; p = 0.031) in the black group only. The overall less favorable NO profile and higher CK and MDA levels in the black cohort along with the adverse associations with the uACR may reflect the vulnerability of this cohort to the early development of hypertension.

A Novel Near Infrared Spectroscopy Based Device for Albumin Estimation

In this paper we have proposed a fluorescence based spectroscopy device which can be used to quantitatively estimate the amount of albumin that gets excreted out of our body. Albumin is a significant protein in bio-fluids and performs a wide range of metabolic functions. The dye that has been used as a fluorescent indicator for the presence of albumin in this study has been earlier tested with bovine serum albumin (BSA) and human serum albumin (HSA) with satisfactory results. The method is based on principle of fluorescence in near infrared range (NIR) of 700 to 850 nm by using a novel dye with the test mixture. The chosen near infrared range has a benefit of absence of the auto fluorescence of the bio-molecules present in urine other than the albumin molecules. The system consists of: light source, spectroscopic chamber, sensing and computational unit. The study shows the stability and reproducibility of device so as to avoid fluctuations of voltage and other undesirables. The optimization with bovine serum albumin and human serum albumin has been done and the device can sense as low as 100 nM concentration precisely and accurately.Clinical Relevance-The system being presented is intended for developing a low cost point of care testing device for determining albumin concentration in urine.

Changes in albuminuria during the spontaneous breathing trial: A prospective observational study

BACKGROUND

We hypothesized urine albumin concentration may detect the early increasing cardiac load during the spontaneous breathing trial (SBT). The purpose of our study is to determine whether the changes in urine albumin concentration before and after the SBT correlate with SBT outcome.

METHODS

This prospective observational study was conducted from January 2013 to September 2013. Patients receiving endotracheal tube intubation due to acute respiratory failure were included. Urine albumin concentration was measured upon admission to the intensive care unit, before and after the SBT.

RESULTS

A total of 211 patients with respiratory failure were screened. Finally, 69 patients were included for analysis. Among the 69 patients received the SBT, 61 patients passed the SBT while 8 patients didn't. Urine albumin concentration upon admission was 251.00 ± 108.21 mg/g in the SBT success group and 260.87 ± 77.95 mg/g in the SBT failure group (p = 0.97). The mean percent change in urine albumin concentration during the SBT was significantly higher in the SBT failure group (+58.44%) than in the SBT success group (+13.11%) (p = 0.02). Univariable and multivariable logistic regression model showed that the difference of urine albumin concentration before and after the SBT correlated significantly with SBT failure (adjusted OR:1.04, p = 0.01).

CONCLUSION

This open label pilot study demonstrates the significant association of the changes in urine albumin concentration with SBT outcome. Further study is warranted to investigate the predictive value of urine albumin concentration.

Bidirectional and Temporal Association Between Hypertension and Microalbuminuria: A Longitudinal Study in Chinese Adults

Background Although hypertension and microalbuminuria are closely interrelated, the magnitude and temporal sequence of the bidirectional association between hypertension and microalbuminuria are largely unknown. We aimed to delineate the bidirectional and temporal relationship between hypertension and microalbuminuria. Methods and Results Leveraging a longitudinal cohort of Chinese adults who had blood pressure and urinary albumin measured twice 4 years apart, we examined the temporal association between hypertension and microalbuminuria by bidirectional and cross-lagged panel analysis. All participants were free of cardiovascular disease and chronic kidney disease at baseline. Bidirectional association analysis found that baseline microalbuminuria predicted the risk of incident hypertension (odds ratio=1.75, P=0.028), and baseline blood pressure also significantly predicted the risk of microalbuminuria (odds ratios=1.27 and 1.21 for a per-SD increase in systolic and diastolic blood pressure, respectively; all P<0.05). Cross-lagged panel analysis demonstrated a bottom-line significant relationship of baseline systolic blood pressure to follow-up urinary albumin ( P=0.079), which is significantly weaker than the other direction of the relationship of baseline urinary albumin to follow-up blood pressures (all P<0.001). Conclusions These findings indicate a significant bidirectional association between microalbuminuria and hypertension in Chinese adults. Elevated urinary albumin excretion is more likely to precede hypertension. The causality between microalbuminuria and hypertension needs further investigation.

Impact of Kidney Function on Cardiovascular Risk and Mortality: A Comparison of South Asian and European Cohorts

BACKGROUND

Evidence is limited on ethnic differences in associations between kidney function markers and mortality or cardiovascular disease (CVD).

METHODS

Baseline cross-sectional analysis and longitudinal follow-up study of a UK population-based cohort of 1,116 Europeans and 1,104 South Asians of predominantly Indian descent, age 52 ± 7 years at baseline (1988-1991). Kidney function was estimated using Cystatin C and creatinine-based chronic kidney disease (CKD) Epidemiology Collaboration estimated glomerular filtration rate (eGFR) equations, and urinary albumin-creatinine ratio (ACR). Mortality was captured at 27 years, and incident CVD at 22 years, from death certification, medical records and participant report. Longitudinal associations between eGFR/ACR and mortality/incident CVD were examined using Cox models.

RESULTS

eGFRcys was lower and ACR higher in South Asians than Europeans. eGFRcys and -eGFRcreat were more strongly associated with outcomes in Europeans than South Asians. Conversely, associations between ACR and outcomes were greater in South Asians than Europeans, for example, for CVD mortality: HRs (95% CI) adjusted for CVD risk factors and ACR/eGFRcys as appropriate, p for ethnicity interaction: eGFRcys: Europeans: 0.76 (0.62-0.92), South Asians: 0.92 (0.78-1.07), p = 0.05, eGFRcreat: Europeans 0.81 (0.67-0.99), South Asians 1.18 (0.97-1.41), p = 0.002, ACR: -Europeans: 1.24 (1.08-1.42), South Asians: 1.39 (1.25-1.57), p= 0.23. Addition of all CKD measures to a standard CVD risk factor model modestly improved prediction capability in -Europeans; in South Asians only ACR contributed to improvement.

CONCLUSIONS

Strong associations between ACR and outcomes in South Asians of predominantly Indian origin, and null associations for eGFRcys and eGFRcreat, suggest that ACR may have greater utility in CVD risk prediction in South Asians. Further work is needed to validate these -findings.

Association between Brachial-Ankle Pulse Wave Velocity and Microalbuminuria and to Predict the Risk for the Development of Microalbuminuria Using Brachial-Ankle Pulse Wave Velocity Measurement in Type 2 Diabetes Mellitus Patients

Brachial-ankle pulse wave velocity (baPWV) provides a useful means of assessing cardiovascular events and diabetic complications. However, the nature of associations between baPWV and microalbuminuria (MAU) and its presence in Type 2 diabetes mellitus (Type 2 DM) have rarely been investigated. This study aimed to examine the association between baPWV and MAU coupled with prediction of MAU using baPWV measurement among Type 2 DM patients. In this cross-sectional study, we enrolled 424 Type 2 DM patients who visited the cardiology and endocrinology department at a tertiary level health care facility, Republic of Korea between 1 January 2006 to 31 December 2008. Clinical and laboratory data were collected, and risk factors associated with MAU and prediction of risk for the development of MAU using baPWV measurement. The association between MAU and baPWV was examined using multivariable logistic regression analysis and predicted MAU by using receiver operating characteristic (ROC) curve analysis. Of the 424 Type 2 DM patients, 93 (21.9%) had MAU (20-200 μg/min). baPWV (cm/sec) was found to be significantly correlated with MAU levels (ug/min) (r = 0.791, p < 0.001). Further, baPWV was significantly associated MAU with higher odds ratio (adjusted odds ratio (AOR) 10.899; 95% confidence interval (CI) (4.518-26.292)). Similarly, smoking (AOR 10.899; 95% CI (4.518-26.292)), and low-density lipoprotein (LDL)-cholesterol (mg/dL) (AOR 1.017; 95% CI (1.001-1.033)) were also significantly associated with MAU. The appropriate cut-off value for baPWV to predict MAU 20 μg/min in our study was 1700 cm/sec (area under ROC curve = 0.976). This study shows that baPWV, cigarette smoking, and LDL-cholesterol are associated with MAU in Type 2 DM patients and suggests that a baPWV cut-off of 1700 cm/sec could be used to predict the presence of MAU (20 μg/min) in Type 2 DM patients in the Korean community.

A new strategy for vascular complications in young people with type 1 diabetes mellitus

Diabetes vascular complications, including cardiovascular disease, diabetic nephropathy and retinopathy, have a negative effect on the long-term prognosis of young people with type 1 diabetes mellitus (T1DM). Poor glycaemic control and consequent increased HbA_1c levels are major risk factors for the development of vascular complications. HbA_1c levels are the main focus of current management strategies; however, the recommended target is rarely achieved in adolescents. Thus, a clear need exists for improved biomarkers to identify high-risk young people early and to develop new intervention strategies. Evidence is accumulating that early increases in urinary albumin excretion could be predictive of adolescents with T1DM who are at an increased risk of developing vascular complications, independent of HbA_1c levels. These findings present an opportunity to move towards the personalized care of adolescents with T1DM, which takes into consideration changes in albumin excretion and other risk factors in addition to HbA_1c levels.

The effect of atorvastatin on cardiometabolic risk factors in women with non-classic congenital adrenal hyperplasia: A pilot study

BACKGROUND

Individuals with non-classic congenital adrenal hyperplasia (NC-CAH) often show evidence of hyperandrogenism, including premature pubarche, accelerated linear growth velocity, short final height, hirsutism, acne, alopecia, impaired ovulation, menstrual dysfunction and subfertility. Although statins were found to reduce elevated levels of androgens in subjects with this disorder, no previous study has investigated whether 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors affect cardiometabolic risk factors in patients with NC-CAH.

METHODS

We studied 12 women with NC-CAH, 6 of whom because of coexisting hypercholesterolemia received atorvastatin (20-40 mg daily). Circulating levels of lipids, glucose homeostasis markers, plasma levels of androgens, 17-hydroxyprogesterone, high-sensitivity C-reactive protein (hsCRP), uric acid, fibrinogen, homocysteine and 25-hydroxyvitamin D, as well as urinary albumin-to-creatinine ratio (UACR) were determined at the beginning of the study and 12 weeks later.

RESULTS

Beyond affecting plasma lipids, atorvastatin reduced circulating levels of testosterone, dehydroepiandrosterone sulphate, androstenedione and 17-hydroxyprogesterone, and decreased free androgen index. Moreover, atorvastatin caused a decrease in plasma levels/urinary loss of uric acid, hsCRP, homocysteine and UACR, and insignificantly increased circulating levels of 25-hydroxyvitamin D. The drug produced no effect on plasma fibrinogen. The effect of atorvastatin on hsCRP, uric acid, homocysteine, 25-hydroxyvitamin D and UACR correlated with the magnitude of reduction in 17-hydroxyprogesterone and androgens.

CONCLUSION

Our results suggest that statin therapy reduces cardiometabolic risk in women with NC-CAH.

Oxidative Stress and the Kidney in the Space Environment

In space, the special conditions of hypogravity and exposure to cosmic radiation have substantial differences compared to terrestrial circumstances, and a multidimensional impact on the human body and human organ functions. Cosmic radiation provokes cellular and gene damage, and the generation of reactive oxygen species (ROS), leading to a dysregulation in the oxidants–antioxidants balance, and to the inflammatory response. Other practical factors contributing to these dysregulations in space environment include increased bone resorption, impaired anabolic response, and even difficulties in detecting oxidative stress in blood and urine samples. Enhanced oxidative stress affects mitochondrial and endothelial functions, contributes to reduced natriuresis and the development of hypertension, and may play an additive role in the formation of kidney stones. Finally, the composition of urine protein excretion is significantly altered, depicting possible tubular dysfunction.

The comorbidity of increased arterial stiffness and microalbuminuria in a survey of middle-aged adults in China

BACKGROUND

Increased arterial stiffness (iAS) and microalbuminuria (MAU), which may occur simultaneously or separately in the general population and share similar risk factors, are markers of macro- and microvascular injuries. Our research investigated the comorbidity of iAS and MAU in the middle-aged population and examined the heterogeneous effects of metabolic risk factors on iAS and MAU.

METHODS

We selected 11,911 individuals aged 45 to 60 years who underwent a health examination at the 3rd Xiangya Hospital between 2010 and 2014. Metabolic syndrome (MetS) was determined according to IDF/NHLBI/AHA-2009 criteria. Multinomial logistic regression was applied to evaluate the influence of MetS, components of MetS and clusters of MetS on the co-occurrence (MAU(+)/iAS(+)) or non-co-occurrence (MAU(+)/iAS(-) and MAU(-)/iAS(+)) of MAU and iAS.

RESULTS

Reference group was MAU(-)/iAS(-). A positive effect of MetS on the presence of MAU(+)/iAS(-), MAU(-)/iAS(+), or MAU(+)/iAS(+) is listed in ascending order based on odds ratios (ORs = 2.11, 2.41, 4.61, respectively; P < 0.05). Compared with MAU(+)/iAS(-), Elevated blood pressure (BP) (OR = 1.62 vs. 4.83, P < 0.05), triglycerides(TG) (OR = 1.20 vs. 1.37, P < 0.05) were more strongly associated with MAU(-)/iAS(+), whereas fasting blood glucose (FBG) was less associated (OR = 1.37 vs. 1.31, P < 0.05). Decreased high-density lipoprotein cholesterol(HDL-c) (OR = 1.84, P < 0.01) and elevated waist circumference(WC) (OR = 1.28 P < 0.01) were the most strongly associated with MAU(+)/iAS(-). Compared with the individuals without MetS, individuals with the elevated BP, FBG, TG and decreased HDL-c cluster had the greatest likelihood of presenting a MAU(-)/iAS(+) (OR = 5.98, P < 0.01) and MAU(+)/iAS(+) (OR = 13.17, P < 0.01), these likelihood was even greater than the cluster with simultaneous alteration in all five MetS components (OR = 3.89 and 10.77, respectively, P < 0.01), which showed the most strongly association with MAU(+)/iAS(+) (OR = 5.22, P < 0.01).

CONCLUSION

Based on the heterogeneous influences of MetS-related risk factors on MAU and iAS, these influences could be selectively targeted to identify different types of vascular injuries.

Proton Pump Inhibitors, Nephropathy, and Cardiovascular Disease in Type 2 Diabetes: The Fremantle Diabetes Study

CONTEXT

There is emerging evidence of various adverse effects of chronic proton pump inhibitor (PPI) therapy.

OBJECTIVE

To assess the impact of PPI use on nephropathy and cardiovascular disease (CVD) risk in type 2 diabetes.

DESIGN

Longitudinal observational study.

SETTING

Urban-dwelling community.

PATIENTS

Patients with type 2 diabetes from the Fremantle Diabetes Study Phase II and on stable renin-angiotensin system blocking therapy were divided into those remaining untreated with a PPI (group 1, n = 686), on PPI therapy throughout (group 2, n = 174), and commencing (group 3, n = 109) or discontinuing regular PPI therapy (group 4, n = 67) during the 2 years between assessments.

MAIN OUTCOME MEASURES

Changes (Δ) in urinary albumin/creatinine ratio (uACR), estimated glomerular filtration rate (eGFR), and predicted 5-year CVD risk.

RESULTS

There were no statistically significant differences in ΔuACR between groups [analysis of variance (ANOVA), P = 0.36], but ΔeGFR was different (ANOVA, P = 0.002), with group 3 exhibiting a greater reduction than group 1 [adjusted mean difference (95% confidence interval), -2.7 (-4.5 to -0.8) mL/min/1.73 m2; P = 0.005]. The Δ5-year CVD risk showed a similar pattern (ANOVA, P < 0.001), with group 3 having a greater increase than group 1 [adjusted mean difference (95% confidence interval), 1.7% (0.6% to 2.8%); P = 0.002].

CONCLUSIONS

Although PPI use was not associated with a sustained adverse effect on uACR, the association between PPI initiation and both worsening nephropathy and increasing 5-year CVD risk has potential clinical implications in type 2 diabetes.

Different associations of albuminuria with total and cardiovascular mortality by concentrations of persistent organic pollutants in the elderly

Epidemiologic studies have indicated that albuminuria is associated with mortality from all causes and cardiovascular disease (CVD), with substantial heterogeneity. We evaluated if the associations of urine albumin creatinine ratio (ACR) with all-cause and CVD mortality differed depending on serum concentrations of persistent organic pollutants (POPs), strong lipophilic chemical mixtures with very long half-lives, which are recently linked to many degenerative diseases. Study subjects were participants of the National Health and Nutrition Examination Survey 1999-2004 who were 60 years or older at baseline (n=1215 and 1067 for organochlorine pesticides (OCPs) and other POPs, respectively). They were followed-up through 2011 (mean follow-up periods: 8.1 and 8.0 years for OCPs and other POPs, respectively). The associations between the ACR and all-cause mortality significantly differed by the serum levels of POPs, especially organochlorine pesticides (OCPs; P_interaction<0.01). Stratified analyses indicated that the associations between ACR and all-cause mortality became stronger as the serum levels of OCPs increased. Among the elderly with the highest tertile of OCPs, the adjusted hazard ratios were 1.0, 1.1, and 2.9 (P_trend<0.01) across the categories of ACR (<10, 10-<30, and ≥30mg/g); however, ACR was not clearly related to mortality among the elderly with the lowest tertile of OCPs. CVD mortality showed similar interactions, as noted for all-cause mortality (P_interaction<0.01). The different associations between albuminuria and mortality by the serum OCP levels and the little association among the elderly with low serum OCPs levels suggest that OCPs play an important role in albuminuria-related death risk. However, these findings need to be replicated in other cohort studies.

Dipstick proteinuria level is significantly associated with pre-morbid and in-hospital functional status among hospitalized older adults: a preliminary study

Although chronic kidney disease (CKD) is associated with functional decline, whether proteinuria alone is associated with functional statuses over the course of acute illnesses independent of CKD is unclear. During 2014, we prospectively enrolled non-dialysis patients aged ≥65 years, and all participants underwent spot dipstick urinalysis on admission, divided into 3 groups according to the results (none, trace to 1 + , and 2 + or higher); functional status was evaluated using the pre-morbid and in-hospital Barthel index (BI) scores. Of 136 community-dwelling elderly patients enrolled (age 80.7 ± 8.2 years, with 19% having CKD), 17%, 57%, and 26% had no, trace to 1 + , or 2 + or higher proteinuria. Overall pre-morbid, on-admission, and on-discharge BI scores were 50.4 ± 41.9, 38.6 ± 31.8, and 38.7 ± 35.3, respectively with significant negative correlations with proteinuric severity on admission. Finally, multivariate linear stepwise regression analysis with backward variable selection found that dipstick proteinuric severity was significantly associated with pre-morbid, on-admission, and on-dischrage BI scores (p = 0.048, <0.01, and <0.01, respectively), independent of diabetes and CKD. This relationship between dipstick proteinuric levels and functional status of hospitalized elderly suggests an under-recognized association. Prospective evaluation of long-term outcome is needed.

Plasma Molecular Signatures in Hypertensive Patients With Renin–Angiotensin System Suppression

Albuminuria is a risk factor strongly associated with cardiovascular disease, the first cause of death in the general population. It is well established that renin–angiotensin system suppressors prevent the development of new-onset albuminuria in naïf hypertensive patients and diminish its excretion, but we cannot forget the percentage of hypertensive patients who develop de novo albuminuria. Here, we applied multiple proteomic strategy with the purpose to elucidate specific molecular pathways involved in the pathogenesis and provide predictors and chronic organ damage indicators. Briefly, 1143 patients were followed up for a minimum period of 3 years. One hundred and twenty-nine hypertensive patients chronically renin–angiotensin system suppressed were recruited, classified in 3 different groups depending on their albuminuria levels (normoalbuminuria, de novo albuminuria, and sustained albuminuria), and investigated by multiple proteomic strategies. Our strategy allowed us to perform one of the deepest plasma proteomic analysis to date, which has shown 2 proteomic signatures: (1) with predictive value of de novo albuminuria and (2) sustained albuminuria indicator proteins. These proteins are involved in inflammation, immune as well as in the proteasome activation occurring in situations of endoplasmic reticulum stress. Furthermore, these results open the possibility of a future strategy based on anti-immune therapy to treat hypertension which could help to prevent the development of albuminuria and, hence, the progression of kidney damage.

Urinary albumin excretion in patients with rheumatoid arthritis in a large cross-sectional study

While there is a lot of evidence published on the association of cardiovascular (CV) disease and rheumatoid arthritis (RA), little is known about urinary albumin excretion (UAE)-a marker of CV risk-in this particular high-risk population. Therefore, we investigated UAE in a large cross-sectional study. We used data from the US National Health and Nutrition Examination Survey (NHANES), including the years 2007-2012. Primary outcome was the proportion of patients with a urinary albumin-creatinine ratio (ACR) >30 mg/g. A total of 14,648 study participants (representing a population size of 174,663,008) with available ACR were included in the study (14,179 without RA and 469 with RA). In the RA group, the proportion of patients with an ACR >30 mg/g was 10.46 % (95 % CI 7.47-14.45 %) and in the non-RA group this proportion was 13.39 % (95 % CI 12.65-14.16 %; p = 0.09). There was a strong association between RA and DM (OR 5.84; 95 % CI 4.48-7.62). In the RA group, significantly more patients had a former CV event (OR 3.01; 95 % CI 2.28-3.97). Adjustments for DM, smoking status, former CV event, age, systolic blood pressure, and gender did not substantially alter the association between RA and ACR >30 mg/g (OR 0.82; 95 % CI 0.51-1.33). We did not find evidence for a difference in UAE in patients with or without RA, despite the fact that RA was associated with DM and, in addition, RA patients more often had a previous CV event. These findings may support the assumption that despite an increased CV risk, UAE does not play a major role in RA patients.

Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients.

Akt Links Insulin Signaling to Albumin Endocytosis in Proximal Tubule Epithelial Cells

Diabetes mellitus (DM) has become an epidemic, causing a significant decline in quality of life of individuals due to its multisystem involvement. Kidney is an important target organ in DM accounting for the majority of patients requiring renal replacement therapy at dialysis units. Microalbuminuria (MA) has been a valuable tool to predict end-organ damage in DM but its low sensitivity has driven research efforts to seek other alternatives. Albumin is taken up by albumin receptors, megalin and cubilin in the proximal tubule epithelial cells. We demonstrated that insulin at physiological concentrations induce albumin endocytosis through activation of protein kinase B (Akt) in proximal tubule epithelial cells. Inhibition of Akt by a phosphorylation deficient construct abrogated insulin induced albumin endocytosis suggesting a role for Akt in insulin-induced albumin endocytosis. Furthermore we demonstrated a novel interaction between Akt substrate 160kDa (AS160) and cytoplasmic tail of megalin. Mice with type 1 DM (T1D) displayed decreased Akt, megalin, cubilin and AS160 expression in their kidneys in association with urinary cubilin shedding preceding significant MA. Patients with T1D who have developed MA in the EDC (The Pittsburgh Epidemiology of Diabetes Complications) study demonstrated urinary cubilin shedding prior to development of MA. We hypothesize that perturbed insulin-Akt cascade in DM leads to alterations in trafficking of megalin and cubilin, which results in urinary cubilin shedding as a prelude to MA in early diabetic nephropathy. We propose that utilization of urinary cubilin shedding, as a urinary biomarker, will allow us to detect and intervene in diabetic nephropathy (DN) at an earlier stage.

Use of Contrast-Enhanced Ultrasound to Study Relationship between Serum Uric Acid and Renal Microvascular Perfusion in Diabetic Kidney Disease

Purpose. To investigate the relationship between uric acid and renal microvascular perfusion in diabetic kidney disease (DKD) using contrast-enhanced ultrasound (CEUS) method. Materials and Methods. 79 DKD patients and 26 healthy volunteers were enrolled. Renal function and urine protein markers were tested. DKD patients were subdivided into two groups including a normal serum uric acid (SUA) group and a high SUA group. Contrast-enhanced ultrasound (CEUS) was performed, and low acoustic power contrast-specific imaging was used for quantitative analysis. Results. Normal controls (NCs) had the highest levels of AUC, AUC1, and AUC2. Compared to the normal SUA DKD group, high SUA DKD patients had significantly higher IMAX, AUC, and AUC1 (P < 0.05). DKD patients with low urinary uric acid (UUA) excretion had significantly higher AUC2 compared to DKD patients with normal UUA (P < 0.05). Conclusion. Hyperuricemia in DKD patients was associated with a renal ultrasound image suggestive of microvascular hyperperfusion. The CEUS parameter AUC1 holds promise as an indicator for renal microvascular hyperperfusion, while AUC2 might be a useful indicator of declining glomerular filtration rate in DKD patients with decreased excretion of uric acid.

Microalbuminuria and left ventricular hypertrophy among newly diagnosed black African hypertensive patients: a cross sectional study from a tertiary hospital in Uganda

BACKGROUND

Microalbuminuria is an early manifestation of kidney damage and independently predicts cardiovascular disease (CVD). Left ventricular hypertrophy (LVH) is also an early marker of cardiac manifestation of target organ damage among hypertensive patients. The prognostic significance of microalbuminuria and its correlation with left ventricular hypertrophy has not been extensively studied in African adult hypertensive populations. This study aimed at determining the prevalence of microalbuminuria, LVH in patients with microalbuminuria and the correlation between microalbuminuria and LVH among newly diagnosed black adult hypertensive patients attending a large outpatient hypertension clinic or admitted on the cardiology ward at Mulago national referral and teaching hospital and Uganda Heart Institute in Kampala, Uganda.

METHODS

In this cross-sectional study, 256 newly diagnosed eligible black adult hypertensive patients attending the outpatient hypertension clinic or admitted on the cardiology ward at Mulago national referral and teaching hospital and the Uganda Heart Institute, Kampala Uganda were consecutively recruited over a period of 5 months. Data on socio-demographics, clinical and laboratory findings of the study participants was collected using a pre tested questionnaire. Two spot urine samples were collected to assess for microalbuminuria. Echocardiography (ECHO) was done to assess for the left ventricular mass index using the formula of Teicholz as evidence for early hypertensive heart disease.

RESULTS

The mean age/standard deviation of the study participants was 54.3 ± 6.2 years with a female predominance (162, 63.3%). The prevalence of microalbuminuria among newly diagnosed hypertensive patients was 39.5%. The prevalence of LVH among patients with microalbuminuria was found to be 17%. There was a positive correlation between microalbuminuria and left ventricular hypertrophy among the newly diagnosed adult hypertensive patients at Mulago Hospital (r = 0.185, p = 0.003).

CONCLUSIONS

This study demonstrates that microalbuminuria is highly prevalent among newly diagnosed black hypertensive patients and in the presence of LVH. There is also a positive correlation between microalbuminuria and LVH among newly diagnosed hypertensive patients. Since it is a less costly and readily available test, it can be used to predict presence of LVH especially in resource limited settings where ECHO services are not readily available.

Relationship between serum irisin levels and urinary albumin excretion in patients with type 2 diabetes

AIM

Irisin is first discovered as a potential mediator of obesity related energy homeostasis. Recent studies indicate that irisin is associated with endothelial dysfunction and atherosclerosis in patients with type 2 diabetes. Our objective was to examine the relationship between irisin and urinary albumin excretion in patients with type 2 diabetes.

METHODS

100 newly diagnosed patients with type 2 diabetes and 100 healthy subjects were selected. Serum irisin levels were measured by ELISA, and urine albumin was measured by radioimmunoassay. High resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (flow-mediated arterial dilation, FMD) and after sublingual glyceryltrinitrate.

RESULTS

Patients with type 2 diabetes presented decreased irisin levels when compared to controls (14.12±3.93 versus 28.98±2.56ng/ml, P=0.015).Serum irisin levels in the microalbuminuric and macroalbuminuria subgroup were 9.89±1.56ng/ml and 5.67±1.89ng/ml, respectively, which were significantly lower than those in the normoalbuminuria (15.97±3.12ng/ml). In comparison to microalbuminuric subgroup, macroalbuminuria subgroup had lower levels of irisin. By dividing the distribution of serum irisin levels into quartiles, FMD was increased gradually with the increase of serum irisin levels (P<0.001). Multiple stepwise linear regression analysis showed that FMD (β=0.75, P=0.002), 2-hBG (β=-0.25, P=0.038) and UAE (β=-0.87, P=0.008) were significantly associated with irisin. Pearson's correlation analyses showed a negative correlation between irisin and logUAE (r=-0.57) and between FMD and logUAE (r=-0.47), and positive correlations between irisin and FMD (r=0.51).

CONCLUSIONS

Decreased plasma levels of irisin seem to be associated with UAE and FMD in patients with type 2 diabetes.

Increased risk of end-stage renal disease among hip fracture patients

BACKGROUND

Inflammation-related microvasculr disease, albuminuria, and rapid deterioration of renal function can accelerate the development of end-stage renal disease (ESRD). The role of hip fracture (HFr), a disorder that involves inflammation, in the development of ESRD has not been fully investigated. This study explored whether HFr increases the risk of ESRD.

METHODS

Taiwan National Health Insurance inpatient claims were used to identify 83,550 patients newly diagnosed with HFr from 2000 to 2006, and 83,550 age- and sex-matched patients without HFr were randomly selected for comparison. Hazards of ESRD combined with HFr, comorbidities, including hypertension, hyperlipidemia, peripheral arterial disease, osteoporosis and asthma, and general health status, with Charlson comorbidity index (CCI), were assessed using data to the end of 2011.

RESULTS

ESRD risk was 1.42-fold higher (95% confidence interval [CI]:1.29-1.33) in the HFr cohort than in the control group, which was computed using the Cox proportional model. Age-specific analysis revealed that the adjusted hazard ratios (aHRs) of ESRD for HFr patients increased slightly as age increased, with an aHR of 1.56 (95% CI:1.35-1.81) for patients 65-74 years old, which gradually decreased to 0.88 (95% CI:0.66-1.18) for patients ≥ 85 years old. ESRD risk increased as HFr severity increased, with an aHR of 6.71 (95% CI:5.90-7.63) for patients with severe HFr.

CONCLUSION

This study is the first to report that HFr, in combination with underlying osteoporosis-related chronic illness, microvascular disease and chronic inflammation, is associated with an increased risk of ESRD, particularly among relatively younger people.

Urine albumin-creatinine ratio in women with gestational diabetes: its link with glycaemic status

BACKGROUND

Micro-albuminuria has been established as a marker for micro-vascular disease. Spot urine albumin-to-creatinine ratio (UACR), even in the high normal range, predicts future cardiovascular events. The value of UACR in women with gestational diabetes mellitus (GDM) during pregnancy is uncertain.

AIM

The objectives of this study were to assess the associations between UACR (performed at the time of GDM diagnosis) and various maternal parameters and to evaluate its correlation with pregnancy outcomes.

MATERIALS AND METHODS

We conducted a retrospective review of women with GDM who attended antenatal clinics at a single centre between March 2010 and September 2013.

RESULTS

Among 1015 women included in this study, high UACR levels were associated with advancing maternal age, maternal obesity, gestational hypertension, elevated glycosylated haemoglobin (HbA1c) and high fasting glucose level. After adjustments for various maternal factors, only advancing age, HbA1c and fasting glucose level were associated with UACR. In terms of pregnancy outcomes, elevated UACR was not associated with adverse events, but was a predictor for pre-eclampsia.

CONCLUSIONS

The finding that UACR was associated with glycaemic status in women with GDM suggests early micro-vascular disease may be present in women who had greater degree of hyperglycaemia. This raises the question of whether women with GDM and elevated UACR may be at higher risk of developing cardiovascular disease in the future. Long-term follow-up of this subgroup of women would be worthwhile.

Peripheral arterial disease among adult diabetic patients attending a large outpatient diabetic clinic at a national referral hospital in Uganda: a descriptive cross sectional study

Background

Peripheral arterial disease (PAD) is one of the recognised diabetic macro vascular complications. It is a marker of generalised systemic atherosclerosis and is closely associated with symptomatic coronary and cerebrovascular disease, hence significant morbidity and mortality. Among African adult diabetic populations, screening and diagnosis of PAD is frequently suboptimal. The aim of this study was to determine the prevalence and associated clinical factors of PAD in adult ambulatory diabetic patients attending the outpatient diabetic clinic of Mulago national referral and teaching hospital, Kampala Uganda.

Methods

In this descriptive cross sectional study, 146 ambulatory adult diabetic patients were studied. Information about their socio-demographic and clinical characteristics, fasting lipid profile status, blood pressure, glycated haemoglobin (HbA1c) levels and presence of albuminuria was collected using a pre tested questionnaire. Measurement of ankle brachial index (ABI) to assess for PAD, defined as a ratio less than 0.9 was performed using a portable 5–10 MHz Doppler device. Clinical factors associated with PAD were determined by comparing specific selected characteristics in patients with PAD and those without.

Results

The mean age/standard deviation of the study participants was 53.9/12.4 years with a male predominance (75, 51.4%). PAD was prevalent in 57 (39%) study participants. Of these, 34 (59.6%) had symptomatic PAD. The noted clinical factors associated with PAD in this study population were presence of symptoms of intermittent claudication and microalbuminuria.

Conclusions

This study documents a high prevalence of PAD among adult ambulatory Ugandan diabetic patients. Aggressive screening for PAD using ABI measurement in adult diabetic patients should be emphasised in Uganda especially in the presence of symptoms of intermittent claudication and microalbuminuria.

Elevated brachial-ankle pulse wave velocity is independently associated with microalbuminuria in a rural population

Microalbuminuria is a marker of generalized endothelial dysfunction resulting from arterial stiffness or insulin resistance, and brachial-ankle pulse wave velocity (baPWV) is a good measure of arterial stiffness. We aimed to investigate whether elevated baPWV is independently associated with microalbuminuria. This study included 1,648 individuals aged over 40 who participated in the baseline Multi-Rural Cohort Study conducted in Korean rural communities between 2005 and 2006. Participants were classified into less than 30 mg/g as normoalbuminuria or 30-300 mg/g as microalbuminuriausing urinary albumin creatinine ratio (UACR). The median and Q1-Q3 baPWV values were significantly higher in the microalbuminuric group both in men (1,538, 1,370-1,777 cm/s vs. 1,776, 1,552-2,027 cm/s, P < 0.001) and women (1,461, 1,271-1,687 cm/s vs. 1,645, 1,473-1,915 cm/s, P < 0.001). BaPWV was independently associated with microalbuminuria in both genders after adjusting for pulse rate; fasting blood glucose; triglyceride; homeostatic model assessment insulin resistance (HOMAIR) and, history of hypertension and diabetes. Fasting blood sugar and HOMAIR were judged as having nothing to do with multicolinearity (r = 0.532, P < 0.001). Elevated baPWV was independently associated with microalbuminuria regardless of insulin resistance among rural subjects over 40 yr.

Serum myeloid-related protein 8/14 complex is associated with microalbuminuria in patients with type 2 diabetes

OBJECTIVES

Microalbuminuria (MA) is associated independently with cardiovascular risk and progression of renal disease in patients with diabetes and the normal population. MA is an accepted factor for microvascular defects, in particular in patients with diabetes, and is associated with inflammation. Activated transmigrating macrophages are key cells in these inflammatory processes. Based on the theory that myeloid-related protein 8/14 complex (MRP8/14) is secreted by transmigrating macrophages, we hypothesized that MA was accompanied by elevated MRP8/14 and investigated whether MA predicts MRP8/14 in patients with type 2 diabetes.

METHODS

A total of 86 men with type 2 diabetes were grouped according to urinary albumin excretion in normoalbuminuria and MA. Serum MRP8/14 levels were measured by enzyme-linked immunosorbent assay. Established cardiovascular risk factors were quantified in both groups and compared with urinary albumin excretion.

RESULTS

Albuminuria (mg/day) was positively associated with MRP8/14 (r = 0.34) and systemic blood pressure (r = 0.33). Patients with type 2 diabetes and MA demonstrated significantly higher MRP8/14 levels than patients with normoalbuminuria [median (interquartile range), 1.24 (0.97-2.28) µg/ml versus 0.97 (0.67-1.35) µg/ml, p < 0.05]. Serum creatinine levels, systolic blood pressure (SBP), very low density lipoprotein levels and the incidence of hypertension and coronary artery disease were significantly higher in the group with MA. Both groups did not differ significantly in other cardiovascular risk factors. MA was an independent predictor of serum MRP8/14 levels (β = 0.454) as well as SBP (β = 0.625) and haemoglobin A1c (β = 0.322).

CONCLUSION

Our data demonstrate that albumin excretion is associated with the process of macrophage activation determined by MRP8/14 levels. These data not only suggest tissue inflammation as a factor for elevated cardiovascular risk in patients with type 2 diabetes, they further point to a role of macrophage activation in this process.

The total urine protein-to-creatinine ratio can predict the presence of microalbuminuria

Background

The Kidney Disease: Improving Global Outcomes chronic kidney disease (CKD) guidelines recommend that CKD be classified based on the etiology, glomerular filtration rate (GFR) and degree of albuminuria. The present study aimed to establish a method that predicts the presence of microalbuminuria by measuring the total urine protein-to-creatinine ratio (TPCR) in patients with cardiovascular disease (CVD) risk factors.

Methods and Results

We obtained urine samples from 1,033 patients who visited the cardiovascular clinic at St. Luke's International Hospital from February 2012 to August 2012. We measured the TPCR and the urine albumin-to-creatinine ratio (ACR) from random spot urine samples. We performed correlation, receiver operating characteristic (ROC) curve, sensitivity, and subgroup analyses. There was a strong positive correlation between the TPCR and ACR (R² = 0.861, p<0.001). A ROC curve analysis for the TPCR revealed a sensitivity of 94.4%, a specificity of 86.1%, and an area under the curve of 0.903 for detecting microalbuminuria for a TPCR cut-off value of 84 mg/g of creatinine. The subgroup analysis indicated that the cut-off value could be used for patients with CVD risk factors.

Conclusions

These results suggest that the TPCR with an appropriate cut-off value could be used to screen for the presence of microalbuminuria in patients with CVD risk factors. This simple, inexpensive measurement has broader applications, leading to earlier intervention and public benefit.

Association of renal biochemical parameters with left ventricular diastolic dysfunction in a community-based elderly population in China: a cross-sectional study

Background

Relationship of left ventricular diastolic dysfunction (LVDD) with parameters that could provide more information than hemodynamic renal indexes has not been clarified. We aimed to explore the association of comprehensive renal parameters with LVDD in a community-based elderly population.

Methods

1,166 community residents (aged ≥ 65 years, 694 females) participating in the Shanghai Heart Health Study with complete data of renal parameters were investigated. Echocardiography was used to evaluate diastolic function with conventional and tissue Doppler imaging techniques. Serum urea, creatinine, urea-to-creatinine ratio, estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) were analyzed on their associations with LVDD.

Results

The prevalence of LVDD increased in proportion to increasing serum urea, urea-to-creatinine ratio and UACR. These three renal parameters were found negatively correlated to peak early (E) to late (A) diastolic velocities ratio (E/A), and positively to left atrial volume index; UACR also positively correlated with E to peak early (E’) diastolic mitral annular velocity ratio (E/E’). Serum urea, urea-to-creatinine ratio and UACR correlated with LVDD in logistic univariate regression analysis, and urea-to-creatinine ratio remained independently correlated to LVDD [Odds ratio (OR) 2.82, 95% confidence interval (CI) 1.34–5.95] after adjustment. Serum urea (OR 1.18, 95%CI 1.03–1.34), creatinine (OR 6.53, 95%CI 1.70­–25.02), eGFR (OR 0.22, 95%CI 0.07–0.65) and UACR (OR 2.15, 95%CI 1.42–3.24) were revealed independent correlates of advanced (moderate and severe) LVDD.

Conclusions

Biochemical parameters of renal function were closely linked with LVDD. This finding described new cardio-renal relationship in the elderly population.

Microalbuminuria, kidney function, and daily physical activity

The present study was carried out to investigate independent relationship between daily physical activity, microalbuminuria, and kidney function. The demographic characteristics and laboratory parameters were recorded for all patients. The determination of daily activities was carried out by Nottingham Extended Activities of Daily Living Scale (NEADLS) which was performed for each patient in an interview. Totally 139 patients were enrolled. In the whole group NEADLS score was correlated with age (rho: −0.759, P < 0.0001), clinical systolic blood pressure (rho: −0.212, P: 0.018), blood urea nitrogen (rho: −0.516, P < 0.0001), creatinine (rho: −0.501, P < 0.0001), uric acid (rho: −0.308, P < 0.0001), albumin (rho: 0.382, P < 0.0001), total cholesterol (rho: −0.194, P: 0.022), LDL-cholesterol (rho: −0.230, P: 0.008), hemoglobin (rho: 0.256, P: 0.002), creatinine clearance (rho: 0.565, P < 0.0001), 24-hour urinary protein excretion (rho: −0.324, P < 0.0001), and 24-hour urinary albumin excretion (UAE) (rho: −0.483, P < 0.0001). The multivariate linear regression of independent factors corelated with logarithmically converted NEADLS score (as a dependent variable) has shown that age (P < 0.0001), presence of coronary artery disease (P: 0.011), hemoglobin (P: 0.020), 24-hour creatinine clearance (P: 0.004), and 24-hour urinary albumin excretion (P < 0.0001) were independently corelated with NEADLS score. In conclusion, both UAE and kidney function were independently associated with daily physical activity.