Association of low-grade urinary albumin excretion with left ventricular hypertrophy in the general population: the MONICA/KORA Augsburg Echocardiographic Substudy

Renal Insufficiency Increases the Combined Risk of Left Ventricular Hypertrophy and Dysfunction in Patients at High Risk of Cardiovascular Diseases

BACKGROUND

The identification of asymptomatic structural and functional cardiac abnormalities can help us to recognize early and intervene in patients at pre-heart failure (HF). However, few studies have adequately evaluated the associations of renal function and left ventricular (LV) structure and function in patients at high risk of cardiovascular diseases (CVD).

METHODS

Patients undergoing coronary angiography and/or percutaneous coronary interventions were enrolled from the Cardiorenal ImprovemeNt II (CIN-II) cohort study, and their echocardiography and renal function were assessed at admission. Patients were divided into five groups according to their estimated glomerular filtration rate (eGFR). Our outcomes were LV hypertrophy and LV systolic and diastolic dysfunction. Multivariable logistic regression analyses were conducted to investigate the associations of eGFR with LV hypertrophy and LV systolic and diastolic dysfunction.

RESULTS

A total of 5610 patients (mean age: 61.6 ± 10.6 years; 27.3% female) were included in the final analysis. The prevalence of LV hypertrophy assessed by echocardiography was 29.0%, 34.8%, 51.9%, 66.7%, and 74.3% for the eGFR categories >90, 61-90, 31-60, 16-30, and ≤15 mL/min per 1.73 m² or for patients needing dialysis, respectively. Multivariate logistic regression analysis showed that subjects with eGFR levels of ≤15 mL/min per 1.73 m2 or needing dialysis (OR: 4.66, 95% CI: 2.96-7.54), as well as those with eGFR levels of 16-30 (OR: 3.87, 95% CI: 2.43-6.24), 31-60 (OR: 2.00, 95% CI: 1.64-2.45), and 61-90 (OR: 1.23, 95% CI: 1.07-1.42), were significantly associated with LV hypertrophy. This reduction in renal function was also significantly associated with LV systolic and diastolic dysfunction (all P for trend <0.001). In addition, a per one unit decrease in eGFR was associated with a 2% heightened combined risk of LV hypertrophy and systolic and diastolic dysfunction.

CONCLUSIONS

Among patients at high risk of CVD, poor renal function was strongly associated with cardiac structural and functional abnormalities. In addition, the presence or absence of CAD did not change the associations. The results may have implications for the pathophysiology behind cardiorenal syndrome.

Systemic immune-inflammation index (SII) may be an effective indicator in predicting the left ventricular hypertrophy for patients diagnosed with hypertension

The development of left ventricular hypertrophy (LVH) induced by hypertension is considered a poor prognosis for patients. Similarly, high values of the systemic immune-inflammation index (SII) are correlated with high mortality and morbidity in cardiovascular events. Within this context, our study aimed to detect the association of SII with LVH caused by hypertension. The study included 150 patients diagnosed with hypertension in total and evaluated them as two separate groups with regard to left ventricular mass index (LVMI), including 56 patients (37.3%) with LVH and 94 patients (62.6%) with non-LVH. SII was calculated as platelet × neutrophil/lymphocyte counts. The SII values regarding the group with LVH were detected remarkably higher than those of the non-LVH group (p < 0.001). Additionally, the SII levels of patients with eccentric and concentric hypertrophy were detected higher than those of the normal ventricular geometry and concentric remodeling groups. About curve analysis of the receiver-operating characteristic (ROC), SII values above 869.5 predicted LVH with a sensitivity of 82.1% and specificity of 86.2% (AUC: 0.861; 95% CI: 0.792-0.930; p < 0.001). LVH can be predicted independently through the use of SII in patients diagnosed with hypertension, which may be a simple and easily calculable marker for judging LVH. Moreover, SII can serve as an accurate determinant for the prediction of LVH, in comparison to NLR and PLR.

Hypertension mediated kidney and cardiovascular damage and risk stratification: Redefining concepts

Hypertension mediated organ damage (HMOD) refers to structural or functional changes in arteries or target organs that can be present in long-standing hypertension, but it can be also found in naïve never treated patients. Traditionally, cardiovascular risk is stratified with charts or calculators that tend to underestimate the real cardiovascular risk. The diagnosis of HMOD automatically reclassifies patients to the highest level of cardiovascular risk. Subclinical HMOD can be present already at the diagnosis of hypertension and more than 25% of hypertensives are misclassified with the routine tests recommended by hypertension guidelines. Whether HMOD regression improves cardiovascular outcomes has never been investigated in randomized clinical trials and remains controversial. However, different drugs have been probed with promising results in high cardiovascular risk patients, such as the new antidiabetic or the novel non-steroid mineralocorticoid antagonists. Accordingly, trials have shown that lowering blood pressure reduces cardiovascular events. In this narrative review, we will discuss the role of HMOD in cardiovascular risk stratification, the different types of organ damage, and the evidence available to define whether HMOD can be used as a therapeutic target.

Analysis of cadmium accumulation in community adults and its correlation with low-grade albuminuria

OBJECTIVE

To investigate the effects of chronic non-occupational exposure to cadmium (Cd) on renal injury in residents living in the urban areas of China.

METHODS

In this cross-sectional study, we recruited 1000 participants in Shanghai from August 2015 to August 2017 and collected data on their socio-demographic characteristics, lifetime occupation, and lifestyle factors. The urinary Cd, urinary albumin, urinary creatinine, serum creatinine, urea, and uric acid levels were tested, and 683 participants completed those measurements.

RESULTS

The median urinary Cd concentration of this study population was 0.77 μg/g. The urinary Cd concentration was significantly higher in the female, older, and lower body mass index populations. There were 148 participants with dominant albuminuria who had higher urinary Cd levels than those without dominant albuminuria (0.98 vs. 0.72 μg/g; P < 0.001). Among participants without dominant albuminuria, there were 134 participants with low-grade albuminuria (13.84 ≤ ACR < 30 mg/g) and 401 participants who had normal urinary albumin excretion (ACR < 13.84 mg/g). Compared with those who had normal urinary albumin excretion, those with low-grade albuminuria had significantly higher urinary Cd levels (0.83 vs. 0.69 μg/g; P < 0.001). Among those without dominant albuminuria, participants in the highest quartile of urinary Cd were more likely to have low-grade albuminuria than those in the lowest quartile (Odd's ratio = 2.98; P < 0.001). Further adjustment for age, sex, and BMI or other potential confounding factors did not change the magnitudes of the associations. Moreover, we conducted multivariable stepwise linear regression analysis within 134 low-grade albuminuria participants and demonstrated that urinary Cd concentration (P < 0.001) were independent determinants of urine albumin after adjusting for relevant confounders.

CONCLUSION

The urinary Cd levels observed in Chinese urban adults are substantial and associated with an increased risk of low-grade albuminuria. Our findings suggest that potential sources of environmental Cd exposure should be explored, and the associated renal toxicity should be studied in more detail in future.

Low-grade albuminuria and its relationship with cardiovascular disease risk in hypertensive and diabetic patients in primary health care

OBJECTIVE

To evaluate the presence of LGA and the relationship with the 10-year risk of a cardiovascular event in hypertensive and diabetic patients in Primary Health Care.

STUDY DESIGN

The study design used is cross-sectional.

METHODS

This study was based on the application of questionnaires, anthropometric measurements, and laboratory tests carried out from August 2017 to April 2018. Logistic regression was used to evaluate the odds ratio of the explanatory variables in relation to the highest tercile of LGA. The Framingham risk score was used to assess the 10-year risk of cardiovascular event. The comparison of this score with the LGA terciles was analyzed using ANOVA.

RESULTS

An increase in the 10-year risk of cardiovascular event score was observed with an increasing LGA tercile, and this pattern prevailed after adjusting for confounding variables.

CONCLUSION

An association between LGA and the 10-year risk of cardiovascular event was observed in a representative sample of hypertensive and diabetic patients.

Left ventricular structure and function in patients with chronic kidney disease assessed by 3D echocardiography: the CPH-CKD ECHO study

Cardiovascular disease is the leading cause of mortality amongst patients with chronic kidney disease (CKD). This is the first study using 3-dimensional echocardiography (3DE) to investigate associations between adverse changes of the left ventricle, and different stages of CKD. Participants were recruited from the Copenhagen CKD cohort study and the Herlev-Gentofte CKD cohort study. Patients were stratified according to GFR category (G1 + 2: eGFR ≥ 60 mL/min/1.73 m2, G3: eGFR = 30-59 mL/min/1.73 m2, and G4 + 5: eGFR ≤ 29 mL/min/1.73 m2), and according to albuminuria (A1: UACR < 30 mg/g, A2: 30-300 mg/g, A3: > 300 mg/g). Echocardiograms were analysed for left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), and global strain measures. In adjusted analysis, eGFR groups were adjusted for confounders and albuminuria category, while albuminuria groups were adjusted for confounders and GFR category. The study population consisted of 662 outpatients with CKD and 169 controls. Mean age was 57 ± 13 years, and 61% were males. Mean LVEF and global longitudinal strain (GLS) were increasingly impaired across eGFR groups: LVEF = 60.1%, 58.4%, and 57.8% (p = 0.013), GLS =  - 16.1%, - 14.8%, and - 14.6% (p < 0.0001) for G1 + 2, G3, and G4 + 5. LVMi and prevalence of LV hypertrophy increased with albuminuria severity: mean LVMi = 87.9 g/m2, 88.1 g/m2, and 92.1 g/m2 (p = 0.007) from A1-3. Adjusted analysis confirmed reduced LVEF in G3 compared with G1 + 2, and increased LVMi in A3 compared with A1. Increasingly impaired eGFR was associated with adverse changes in LV systolic function, while albuminuria was associated with adverse changes in LV mass assessed by 3DE. Their associations were independent of each other.

Transiently Observed Trace Albuminuria on Urine Dipstick Test Is Associated With All-Cause Death, Cardiovascular Death, and Incident Chronic Kidney Disease: A National Health Insurance Service-National Sample Cohort in Korea

Introduction

Albuminuria is a well-known risk factor for end-stage kidney disease, all-cause mortality, and cardiovascular mortality, even when the albumin-to-creatinine ratio is <30 mg/g. However, the association between transiently observed trace albuminuria and these major adverse outcomes has not yet been reported. This study aimed to examine the effect of transient albuminuria on these major adverse outcomes using the National Health Insurance Service data in Korea.

Methods and Results

The National Health Insurance Service-National Sample Cohort from Korea, followed from 2002 to 2015, consisted of 1,025,340 individuals, accounting for 2.2% of the total Korean population. We analyzed the effect of transient albuminuria on all-cause death, cardiovascular death, and incident chronic kidney disease (CKD) and compared it with the group without albuminuria. Among 1,025,340 individuals, 121,876 and 2,815 had transient albuminuria and no albuminuria, respectively. Adjusted hazard ratios of the transient albuminuria group for cardiovascular death and incident CKD were 1.76 (1.01–3.08) and 1.28 (1.15–1.43), respectively. There were significant differences in all-cause death, cardiovascular death, and incident CKD between the two groups after propensity score matching (p = 0.0037, p = 0.015, and p < 0.0001, respectively). Propensity score matching with bootstrapping showed that the hazard ratios of the transient albuminuria group for all-cause death and cardiovascular death were 1.39 (1.01–1.92) and 2.18 (1.08–5.98), respectively.

Conclusions

In this nationwide, large-scale, retrospective cohort study, transient albuminuria was associated with all-cause death, cardiovascular death, and incident CKD, suggesting that transient albuminuria could be a risk marker for adverse outcomes in the future, and that its own subclinical phenotype could play an important role during the course of CKD.

Abnormalities in Cardiac Structure and Function among Individuals with CKD: The COMBINE Trial

Background

Individuals with CKD have a high burden of cardiovascular disease (CVD). Abnormalities in cardiac structure and function represent subclinical CVD and can be assessed by cardiac magnetic resonance imaging (cMRI).

Methods

We investigated differences in cMRI parameters in 140 individuals with CKD stages 3b-4 who participated in the CKD Optimal Management with BInders and NicotinamidE (COMBINE) trial and in 24 age- and sex-matched healthy volunteers. Among COMBINE participants, we examined the associations of eGFR, urine albumin-creatinine ratio (UACR), phosphate, fibroblast growth factor 23 (FGF23), and parathyroid hormone (PTH) with baseline (N=140) and 12-month change (N=112) in cMRI parameters.

Results

Mean (SD) ages of the COMBINE participants and healthy volunteers were 64.9 (11.9) and 60.4 (7.3) years, respectively. The mean (SD) baseline eGFR values in COMBINE participants were 32.1 (8.0) and 85.9 (16.0) ml/min per 1.73 m² in healthy volunteers. The median (interquartile range [IQR]) UACR in COMBINE participants was 154 (20.3-540.0) mg/g. Individuals with CKD had lower mitral valve E/A ratio compared with healthy volunteers (for CKD versus non-CKD, β estimate, -0.13; 95% CI, -0.24 to -0.012). Among COMBINE participants, multivariable linear regression analyses showed that higher UACR was significantly associated with lower mitral valve E/A ratio (β estimate per 1 unit increase in natural-log UACR, -0.06; 95% CI, -0.09 to -0.03). This finding was preserved among individuals without baseline CVD. UACR was not associated with 12-month change in any cMRI parameter. eGFR, phosphate, FGF23, and PTH were not associated with any cMRI parameter in cross-sectional or change analyses.

Conclusions

Individuals with CKD stages 3b-4 have evidence of cMRI abnormalities. Albuminuria was independently associated with diastolic dysfunction, as assessed by mitral valve E/A ratio, in individuals with CKD with and without clinical CVD. Albuminuria was not associated with change in any cMRI parameter.

Increased epicardial adipose tissue thickness is associated with microalbuminuria in hypertensive patients with left ventricular hypertrophy

OBJECTIVE

Epicardial adipose tissue (EAT) is a cardiometabolic risk factor, and its possible relationship with hypertension has been previously reported. Microalbuminuria (MA) is associated with target-organ damage, especially in patients with hypertension with left ventricular hypertrophy (LVH) and suggest endothelial dysfunction. This study aimed to investigate the relationship between echocardiographic EAT thickness and presence of MA in patients with hypertension.

METHODS

A total of 297 newly diagnosed hypertension patients who applied to the outpatient clinic were enrolled consecutively in this study. Patients were divided into two groups regarding the presence of LVH in echocardiography. An age and gender matched control group was set including 156 healthy patients without HT. All subjects underwent transthoracic echocardiography for the measurement of EAT thickness. Spot urine samples were collected for the assessment of MA.

RESULTS

In hypertensive patients with LVH, the EAT thicknesses (6.6 ± 1.8 vs 5.3 ± 1.5 vs 5.1 ± 1.3, p < .001; respectively) and prevalence of MA (41.2 vs 20.1 vs 3.2%; p < .001 respectively) were significantly higher than the other two groups. In hypertensive patiens without LVH, no relationship was found between the presence of MA and EAT thickness. In multivariate regression analyses, EAT thickness (OR: 3.141, 95%CI: 2.425-6.123, p < .001) and left ventricular mass index (OR: 1.339, 95%CI: 1.145-2.143, p = .003) were determined as independent predictors for MA development in hypertensive patients with LVH.

CONCLUSION

Measurement of EAT thickness may help to identify high-risk hypertensive patients for target-organ damage especially among patients with LVH.

Albuminuria and other target organ damage in Chinese patients with hypertension and diabetes: A data analysis based on the ATTEND study

AIMS

The relationship between albuminuria and left ventricular hypertrophy (LVH) was well characterized in hypertension (HTN), but not in diabetes. Moreover, most studies have described the correlation between albuminuria and cardiovascular mortality, but not cardiovascular diseases (CVD) morbidity. This study aimed to explore the relationship between albuminuria and LVH, CVD morbidity in patients with HTN, diabetes mellitus (DM) or HTN + DM.

METHODS

Conducted a data analysis based on the demographic, medical history and laboratory data of 2504 patients from the ATTEND study, a national registry study on HTN and DM in Chinese outpatients.

RESULTS

The prevalence of LVH and CVD was 7.7% and 21.5% in HTN + DM, 7.6% and 17.6% in HTN, 3.9% and 5.2% in DM patients. Subjects with HTN + DM implied higher risk of LVH (P = 0.023), CVD (P = 0.001) and 10-year coronary heart disease (CHD) (P < 0.001) than those with DM only. There was no significant relationship between albuminuria and LVH or CVD.

CONCLUSIONS

More than one-fifth of HTN and/or DM patients with microalbuminuria suffered from CVD. Comorbidity of DM and HTN significantly increases cardiovascular events than DM only. No statistical association between albuminuria and LVH or CVD was found.

Increased Proteinuria is Associated with Increased Aortic Arch Calcification, Cardio-Thoracic Ratio, Rapid Renal Progression and Increased Overall and Cardiovascular Mortality in Chronic Kidney Disease

Background: Patients with chronic kidney disease (CKD) are associated with high prevalence rates of proteinuria, vascular calcification and cardiomegaly. In this study, we investigated relationships among proteinuria, aortic arch calcification (AoAC) and cardio-thoracic ratio (CTR) in patients with CKD stage 3A-5. In addition, we investigated correlations among proteinuria and decline in renal function, overall and cardiovascular (CV) mortality. Methods: We enrolled 482 pre-dialysis patients with CKD stage 3A-5, and determined AoAC and CTR using chest radiography at enrollment. The patients were stratified into four groups according to quartiles of urine protein-to-creatinine ratio (U_PCR). Results: The patients in quartile 4 had a lower estimated glomerular filtration rate (eGFR) slope, and higher prevalence rates of rapid renal progression, progression to commencement of dialysis, overall and CV mortality. Multivariable analysis showed that a high U_PCR was associated with high AoAC (unstandardized coefficient β: 0.315; p = 0.002), high CTR (unstandardized coefficient β: 1.186; p = 0.028) and larger negative eGFR slope (unstandardized coefficient β: -2.398; p < 0.001). With regards to clinical outcomes, a high U_PCR was significantly correlated with progression to dialysis (log per 1 mg/g; hazard ratio [HR], 2.538; p = 0.003), increased overall mortality (log per 1 mg/g; HR, 2.292; p = 0.003) and increased CV mortality (log per 1 mg/g; HR, 3.195; p = 0.006). Conclusions: Assessing proteinuria may allow for the early identification of high-risk patients and initiate interventions to prevent vascular calcification, cardiomegaly, and poor clinical outcomes.

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.

Larger nephron size, low nephron number, and nephrosclerosis on biopsy as predictors of kidney function after donating a kidney

It is unclear whether structural findings in the kidneys of living kidney donors predict postdonation kidney function. We studied living kidney donors who had a kidney biopsy during donation. Nephron size was measured by glomerular volume, cortex volume per glomerulus, and mean cross-sectional tubular area. Age-specific thresholds were defined for low nephron number (calculated from CT and biopsy measures) and nephrosclerosis (global glomerulosclerosis, interstitial fibrosis/tubular atrophy, and arteriosclerosis). These structural measures were assessed as predictors of postdonation measured GFR, 24-hour urine albumin, and hypertension. Analyses were adjusted for baseline age, gender, body mass index, systolic and diastolic blood pressure, hypertension, measured GFR, urine albumin, living related donor status, and time since donation. Of 2673 donors, 1334 returned for a follow-up visit at a median 4.4 months after donation, with measured GFR <60 mL/min/1.73 m² in 34%, urine albumin >5 mg/24 h in 13%, and hypertension in 5.3%. Larger glomerular volume and interstitial fibrosis/tubular atrophy predicted follow-up measured GFR <60 mL/min/1.73 m² . Larger cortex volume per glomerulus and low nephron number predicted follow-up urine albumin >5 mg/24 h. Arteriosclerosis predicted hypertension. Microstructural findings predict GFR <60 mL/min/1.73 m² , modest increases in urine albumin, and hypertension shortly after kidney donation.

Serum osteocalcin level as an indicator of low-grade albuminuria in Chinese men free of kidney disease

OBJECTIVE

The presence of low-grade albuminuria (LGA) suggested that the pathophysiology of vascular dysfunction has been initiated. Clear evidence supports a role for osteocalcin in energy metabolism and a great incidence of pathological cardiovascular changes. The observational community-based study aims to examine the association of osteocalcin with LGA, which may provide new insight into potential involvement of osteocalcin in cardiovascular diseases.

METHODS

A total of 1951 adults [58.37 (53.34-63.13) years, 41.3% men] from Shanghai were enrolled. LGA was defined as a urinary albumin-to-creatinine ratio (UACR) < 30 mg/g. Serum osteocalcin was measured using an electrochemiluminescence immunoassay.

RESULTS

Serum osteocalcin level in men decreased with increasing UACR after adjusting for potential covariates (p = 0.045); however, the adjusted association disappeared in women (p = 0.258). Linear regression analysis showed that osteocalcin was a negative variable of UACR in men (standardized β = -0.074, p = 0.030), particularly prominent in non-hyperglycemic, non-hypertensive men, even regardless of estimated glomerular filtration rate (eGFR) (60 ≤ eGFR <90 mL/min/1.73 m², standardized β =-0.422, p = 0.004; ≥ 90 mL/min/1.73 m², standardized β = -0.167, p = 0.037).

CONCLUSION

After controlling for confounders, serum osteocalcin level was independently associated with LGA in men, which suggested that osteocalcin was closely related with atherosclerosis and vascular dysfunction.

Non-alcoholic fatty liver disease is associated with low-grade albuminuria in men without diabetes mellitus

Background: Non-alcoholic fatty liver disease (NAFLD) is associated with the dysregulation of multiple metabolic and inflammatory pathways. These can lead to extrahepatic disorders involving the kidney, a vulnerable organ responsible for extra-renal complications. Evaluating the association between NAFLD and low-grade albuminuria as a renal complication would be helpful to better understand the pathophysiology and extra-hepatic complications of NAFLD. Patients and Methods: Our study extracted data from database obtained a representative population sample. Overall, 3867 men were included in this survey. Our study included only men without diabetes mellitus, with a urinary albumin/creatinine ratio < 30 mg/g (n = 1390). Low-grade albuminuria was defined by a urinary albumin/creatinine ratio within the highest quartile. The fatty liver index was calculated in accordance with Bedogni's equation. We defined the NAFLD group as patients with a fatty liver index of ≥ 60. Results: In the multivariate analysis, the urinary albumin/creatinine ratio in the non-NAFLD and NAFLD groups was 3.05 ± 0.14 and 5.19 ± 0.42, respectively (P < 0.001). The correlation coefficients between the fatty liver index and urinary albumin/creatinine ratio were 0.124 in the Pearson's correlation test and 0.084 in the partial correlation test (P < 0.001 and P = 0.002, respectively). Linear regression analysis showed a positive association between the fatty liver index and the urinary albumin/creatinine ratio on multivariate analysis. Logistic regression analysis showed that the odds ratio for low-grade albuminuria with NAFLD was 2.31 (95% confidence interval, 1.47-3.61; P < 0.001) on the multivariate analysis. Subgroup analyses according to the presence of metabolic syndrome or age (< 50 or ≥ 50 years) showed that the association between NAFLD and the urinary albumin/creatinine ratio was stronger for participants without metabolic syndrome and in those aged < 50 years. Conclusion: NAFLD was associated with low-grade albuminuria in men without diabetes mellitus in this study. Therefore, men with a relatively high fatty liver index or NAFLD should be closely monitored for low-grade albuminuria, especially in absence of metabolic syndrome.

Left ventricular hypertrophy among chronic kidney disease patients in Ghana

Introduction

The presence of left ventricular hypertrophy (LVH) in patients with Chronic Kidney Disease (CKD) is associated with worsening cardiovascular outcomes. There is a dearth of data on LVH in Ghanaian CKD patients.

Methods

This was a cross sectional study carried out at the Komfo Anokye Teaching Hospital (KATH) in Kumasi, Ghana. A questionnaire was used to obtain information on clinical features of CKD. The MDRD-4 equation was used to calculate eGFR. Information on the prevalence and factors associated with electrocardiographic left ventricular hypertrophy were obtained during the initial assessment.

Results

About 64.5% of the 203 participants were male and the mean age was 43.9 ± 17.8 years. Most subjects (79.8%) had stage 5 disease. The mean systolic and diastolic blood pressures were 167.86 ± 39.87 and 101.8 ± 24.4 respectively. Approximately 43% of respondents had LVH. eGFR correlated negatively with LVH. High systolic pressure (OR 4.9, CI 2.4 – 10.4; p < 0.05), high diastolic pressure (OR 8.1, CI 4.0 – 16.1; p < 0.05) increased pulse pressure (OR 3.4 CI 2.6-9.3, p < 0.05), increased body mass index (OR 3.6 CI 1.7-11.2, p < 0.001) as well as male gender (OR 4.7, 95% CI 2.4 – 9.1; p <0.05) were associated with the presence of LVH.

Conclusion

LVH is common in our cohort. High pulse pressure, high DBP, increased BMI and male gender are significant associated factors. Adequate treatment of high blood pressure as well as early detection of LVH and interventions aimed at prevention and/or regression of LVH are to be encouraged.

Kidney Disease Measures and Left Ventricular Structure and Function: The Atherosclerosis Risk in Communities Study

Background

Heart failure is one of the most important complications of chronic kidney disease (CKD). However, few studies comprehensively investigated left ventricular (LV) structure and function in relation to 2 key CKD measures, estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR).

Methods and Results

Among 4175 ARIC (Atherosclerosis Risk in Communities) participants (aged 66–90 years during 2011–2013), we quantified the association of eGFR and ACR with echocardiogram parameters of LV mass, size, systolic function, and diastolic function. Adjusting for demographic variables, both CKD measures were significantly associated with most echocardiogram parameters. Additionally accounting for other potential confounders, we observed significantly higher LV mass index according to reduced eGFR (82.3 [95% confidence interval (CI), 77.6–87.0] g/m² for eGFR <30 mL/min per 1.73 m², 80.9 [95% CI, 77.3–84.6] g/m² for eGFR 30–44 mL/min per 1.73 m², and 80.1 [95% CI, 76.7–83.5] g/m² for eGFR 45–59 mL/min per 1.73 m² compared with 78.7 [95% CI, 75.3–82.1] g/m² for eGFR 75–89 mL/min per 1.73 m²; trend P<0.001). Regarding LV size and function, significant differences were observed for some parameters, particularly at eGFR <30 mL/min per 1.73 m². For ACR, the associations remained significant for most parameters (eg, LV mass index, 91.5 [95% CI, 86.6–96.5] g/m² for ACR ≥300 mg/g and 82.9 [95% CI, 79.4–86.3] g/m² for ACR 30–299 mg/g compared with 77.7 [95% CI, 74.4–81.1] g/m² for ACR <10 mg/g [trend P<0.001]; left arterial volume index, 24.9 [95% CI, 22.9–26.8] and 24.7 [95% CI, 23.4–26.1] mL/m² compared with 23.4 [95% CI, 22.1–24.7] mL/m², respectively [trend P=0.010]). Dichotomizing echo parameters with clinical thresholds, the stronger relationships of ACR over eGFR were further evident.

Conclusions

LV mass was related to both CKD measures, whereas LV size and function were robustly associated with albuminuria. These results have implications for pathophysiological processes behind cardiorenal syndrome and targeted cardiac assessment in patients with CKD.

Association between shift work and microalbuminuria: data from KNHANES(2012-2014)

Background

Shift work disturbs workers’ biological clocks and this condition can cause various health problems including cardiovascular disease. The elevated albuminuria level has been significantly associated with the risk of the cardiovascular disease even within a normal reference range. Therefore, this study aimed to investigate the association between shift work and microalbuminuria.

Methods

Workers aged over 20 years from the fifth and sixth Korea National Health and Nutrition Examination Survey(KNHANES 2012–2014; n = 3000) were included in this analysis. The multiple logistic regression analysis was performed to determine the association between shift work and microalbuminuria stratified by gender.

Results

The prevalence of microalbuminuria in male subjects was higher among day workers, but the difference was not significant. However, the prevalence of microalbuminuria among females was higher in shift workers with statistical significance. For female, the Odds ratio of microalbuminuria in shift workers was significantly higher with 1.86 (95% CI 1.02–3.39) compared with day workers. After dividing into 5 subgroups of the shift work pattern, the odds ratio of microalbuminuria for fixed night shift was significantly higher at 4.68 (95% CI 1.29–17.00) compared with day workers.

Conclusions

This study showed that shift work was associated with microalbuminuria in female workers. Especially we found out the association between fixed night shift and microalbuminuria in female workers.

Epidemiology in Germany-general development and personal experience

Did you ever hear about epidemiology in Germany? Starting from an epidemiological desert the discipline has grown remarkably, especially during the last 10-15 years: research institutes have been established, research funding has improved, multiple curriculae in Epidemiology and Public Health are offered. This increase has been quite steep, and now the epidemiological infrastructure is much better. Several medium-sized and even big population cohorts are ongoing, and the number and quality of publications from German epidemiologists has reached a respectable level. My own career in epidemiology started in the field of environmental health. After German reunification I concentrated for many years on environmental problems in East Germany and observed the health benefits after improvement of the situation. Later, I concentrated on population-based cohorts in newborns (GINI/LISA) and adults (KORA, German National Cohort), and on biobanking. This Essay describes the development in Germany after worldwar 2, illustrated by examples of research results and build-up of epidemiological infractructures worth mentioning.

The association of chronic kidney disease and microalbuminuria with heart failure with preserved vs. reduced ejection fraction

AIMS

Chronic kidney disease (CKD) and microalbuminuria are associated with incident heart failure (HF), but their relative contributions to HF with preserved vs. reduced EF (HFpEF and HFrEF) are unknown. We sought to evaluate the associations of CKD and microalbuminuria with incident HF subtypes in the community-based Framingham Heart Study (FHS).

METHODS AND RESULTS

We defined CKD as glomerular filtration rate <60 mL/min/1.73 m² , and microalbuminuria as a urine albumin to creatinine ratio (UACR) ≥17 mg/g in men and ≥25 mg/g in women. We observed 754 HF events (324 HFpEF/326 HFrEF/104 unclassified) among 9889 FHS participants with serum creatinine measured (follow-up 13 ± 4 years). In Cox models adjusted for clinical risk factors, CKD (prevalence = 9%) was associated with overall HF [hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.01-1.51], but was not significantly associated with individual HF subtypes. Among 2912 individuals with available UACR (follow-up 15 ± 4 years), 192 HF events (91 HFpEF/93 HFrEF/8 unclassified) occurred. Microalbuminuria (prevalence = 17%) was associated with a higher risk of overall HF (HR 1.71, 95% CI 1.25-2.34) and HFrEF (HR 2.10, 95% CI 1.35-3.26), but not HFpEF (HR 1.26, 95% CI 0.78-2.03). In cross-sectional analyses, microalbuminuria was associated with LV systolic dysfunction (odds ratio 3.19, 95% CI 1.67-6.09).

CONCLUSIONS

Microalbuminuria was associated with incident HFrEF prospectively, and with LV systolic dysfunction cross-sectionally in a community-based sample. In contrast, CKD was modestly associated with overall HF but not differentially associated with HFpEF vs. HFrEF. The mechanisms responsible for the relationship of microalbuminuria to future development of HFrEF warrant further investigation.

Urinary Albumin Excretion Reflects Cardiovascular Risk in Postmenopausal Women without Diabetes: The 2011 to 2013 Korean National Health and Nutrition Examination Survey

BACKGROUND

The objective of the current study was to determine whether there was an association between urinary albumin excretion and cardiovascular disease (CVD) risk by estimating the Framingham Risk Score (FRS) in postmenopausal women without diabetes.

METHODS

This study was based on data from the Korea National Health and Nutrition Examination Survey, which was conducted by the Korean Ministry of Health and Welfare in 2011 to 2013. Data on 2,316 postmenopausal women from a total of 24,594 participants was included in the analysis.

RESULTS

The mean FRS was significantly different in each of the urinary albumin to creatinine ratio (UACR) subgroups, and it increased with UACR. The FRS was 12.69±0.12 in the optimal group, 14.30±0.19 in the intermediate normal group, 14.62±0.26 in the high normal group, and 15.86±0.36 in the microalbuminuria group. After fully adjusting for potential confounding factors, high normal levels and microalbuminuria were significantly associated with the highest tertile of FRS ([odds ratio (OR), 1.642; 95% confidence interval (CI), 1.124 to 2.400] and [OR, 3.385; 95% CI, 2.088 to 5.488], respectively) compared with the optimal subgroup. High normal levels and microalbuminuria were also significantly associated with a ≥10% 10-year risk of CVD ([OR, 1.853; 95% CI, 1.122 to 3.060] and [OR, 2.831; 95% CI, 1.327 to 6.037], respectively) after adjusting for potential confounding covariates.

CONCLUSION

Urinary albumin excretion reflects CVD risk in postmenopausal women without diabetes, and high normal levels and microalbuminuria were independently associated with a higher risk of CVD.

Glycated hemoglobin A1c level is associated with high urinary albumin/creatinine ratio in non-diabetic adult population

BACKGROUND

Regarding the association between glycated hemoglobin A1c (HbA1c) levels and microvascular complications, high HbA1c level in participants without diabetes mellitus (DM) may be associated with a high urinary albumin-to-creatinine ratio (UACR).

PATIENTS AND METHODS

Twelve thousand seven hundred and seventy four participants without DM were included in this study. The participants were divided into three groups according to HbA1c levels: a Low group (<5.7%), Middle group (5.7-6.0%), and High group (>6.0%). A high UACR was defined as UACR ≥3.9 mg/g for men and UACR ≥7.5 mg/g for women.

RESULTS

The proportions of participants with a high UACR in the Low, Middle, and High groups were 22.4%, 27.9%, and 38.1%, respectively. Both univariate and multivariate analyses showed that logUACR was greatest in the High group compared to the other groups. For participants without metabolic syndrome (MetS), the proportions of participants with high UACR and logUACR values were greatest in the High group compared to the other groups. For participants with MetS, no differences were found for proportions of participants with high UACR and logUACR values in the Low, Middle, and High groups.

CONCLUSION

Non-DM participants with relatively high HbA1c levels should be closely monitored for UACR, especially if participants do not have MetS. KEY MESSAGES HbA1c level was positively associated with the proportion of participants with a high UACR and logUACR in participants without DM. For participants without MetS, the proportion of participants with a high UACR was greater in the High group than in the other groups and logUACR was greatest in the High group compared to the other groups. For participants with MetS, there were significant associations between HbA1c and the proportion of participants with a high UACR as a categorical variable or logUACR as a continuous variable, but the statistical significance of this finding was weak. No differences were found for proportions of participants with high UACR and logUACR values in the Low, Middle, and High groups.

Markers of kidney disease and risk of subclinical and clinical heart failure in African Americans: the Jackson Heart Study

BACKGROUND

African Americans and patients with chronic kidney disease (CKD) are at high risk for clinical heart failure (HF). In this study, we aimed to determine the association of markers of kidney disease with subclinical HF (by echocardiogram) and risk of clinical HF among a large, well-characterized community-based cohort of African American patients. We also examined whether the association of markers of kidney disease with HF was attenuated with adjustment for echocardiographic measures.

METHODS

We studied participants in the Jackson Heart Study, a large community-based cohort of African Americans. Estimated glomerular filtration rate (eGFR) and urine albumin:creatinine ratio (ACR) were measured at baseline. We tested the association of eGFR and urine ACR with left ventricular mass (LVM), left ventricular ejection fraction (LVEF) and physician-adjudicated incident HF.

RESULTS

Among the 3332 participants in the study, 166 (5%) had eGFR <60 mL/min/1.73 m² and 405 (12%) had urine ACR ≥30 mg/g. In models adjusted for demographics, comorbidity and the alternative measure of kidney disease, lower eGFR and higher urine ACR were associated with higher LVM {β-coefficient 1.54 [95% confidence interval (CI) 0.78-2.31] per 10 mL/min/1.73 m² decrease in eGFR and 2.87 (95% CI 1.85-3.88) per doubling of urine ACR}. There was no association of eGFR and urine ACR with LVEF [β-coefficient -0.12 (95% CI -0.28-0.04) and -0.11 (95% CI -0.35-0.12), respectively]. There was no association of eGFR with the risk of incident HF [HR 1.02 (95% CI 0.91-1.14) per 10 mL/min/1.73 m² decrease], while there was a significant association of urine ACR [HR 2.22 (95% CI 1.29-3.84) per doubling of urine ACR]. This association was only modestly attenuated with adjustment for LVM [HR 1.95 (95% CI 1.09-3.49)].

CONCLUSIONS

Among a community-based cohort of African Americans, lower eGFR and higher ACR were associated with higher LVM. Furthermore, higher urine ACR was associated with incident HF, which was not entirely explained by the presence of left ventricular disease.

Methodology used in studies reporting chronic kidney disease prevalence: a systematic literature review

Background

Many publications report the prevalence of chronic kidney disease (CKD) in the general population. Comparisons across studies are hampered as CKD prevalence estimations are influenced by study population characteristics and laboratory methods.

Methods

For this systematic review, two researchers independently searched PubMed, MEDLINE and EMBASE to identify all original research articles that were published between 1 January 2003 and 1 November 2014 reporting the prevalence of CKD in the European adult general population. Data on study methodology and reporting of CKD prevalence results were independently extracted by two researchers.

Results

We identified 82 eligible publications and included 48 publications of individual studies for the data extraction. There was considerable variation in population sample selection. The majority of studies did not report the sampling frame used, and the response ranged from 10 to 87%. With regard to the assessment of kidney function, 67% used a Jaffe assay, whereas 13% used the enzymatic assay for creatinine determination. Isotope dilution mass spectrometry calibration was used in 29%. The CKD-EPI (52%) and MDRD (75%) equations were most often used to estimate glomerular filtration rate (GFR). CKD was defined as estimated GFR (eGFR) <60 mL/min/1.73 m² in 92% of studies. Urinary markers of CKD were assessed in 60% of the studies. CKD prevalence was reported by sex and age strata in 54 and 50% of the studies, respectively. In publications with a primary objective of reporting CKD prevalence, 39% reported a 95% confidence interval.

Conclusions

The findings from this systematic review showed considerable variation in methods for sampling the general population and assessment of kidney function across studies reporting CKD prevalence. These results are utilized to provide recommendations to help optimize both the design and the reporting of future CKD prevalence studies, which will enhance comparability of study results.

Subclinical Kidney Damage in Hypertensive Patients: A Renal Window Opened on the Cardiovascular System. Focus on Microalbuminuria

The kidney is one of the major target organs of hypertension.Kidney damage represents a frequent event in the course of hypertension and arterial hypertension is one of the leading causes of end-stage renal disease (ESRD).ESRD has long been recognized as a strong predictor of cardiovascular (CV) morbidity and mortality. However, over the past 20 years a large and consistent body of evidence has been produced suggesting that CV risk progressively increases as the estimated glomerular filtration rate (eGFR) declines and is already significantly elevated even in the earliest stages of renal damage. Data was supported by the very large collaborative meta-analysis of the Chronic Kidney Disease Prognosis Consortium, which provided undisputable evidence that there is an inverse association between eGFR and CV risk. It is important to remember that in evaluating CV disease using renal parameters, GFR should be assessed simultaneously with albuminuria.Indeed, data from the same meta-analysis indicate that also increased urinary albumin levels or proteinuria carry an increased risk of all-cause and CV mortality. Thus, lower eGFR and higher urinary albumin values are not only predictors of progressive kidney failure, but also of all-cause and CV mortality, independent of each other and of traditional CV risk factors.Although subjects with ESRD are at the highest risk of CV diseases, there will likely be more events in subjects with mil-to-moderate renal dysfunction, because of its much higher prevalence.These findings are even more noteworthy when one considers that a mild reduction in renal function is very common in hypertensive patients.The current European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines for the management of arterial hypertension recommend to sought in every patient signs of subclinical (or asymptomatic) renal damage. This was defined by the detection of eGFR between 30 mL/min/1.73 m² and 60 mL/min/1.73 m² or the presence of microalbuminuria (MAU), that is an amount of albumin in the urine of 30-300 mg/day or an albumin/creatinine ratio, preferentially on morning spot urine, of 30-300 mg/g.There is clear evidence that urinary albumin excretion levels, even below the cut-off values used to define MAU, are associated with an increased risk of CV events. The relationships of MAU with a variety of risk factors, such as blood pressure, diabetes and metabolic syndrome and with several indices of subclinical organ damage, may contribute, at least in part, to explain the enhanced CV risk conferred by MAU. Nonetheless, several studies showed that the association between MAU and CV disease remains when all these risk factors are taken into account in multivariate analyses. Therefore, the exact pathophysiological mechanisms explaining the association between MAU and CV risk remain to be elucidated. The simple search for MAU and in general of subclinical renal involvement in hypertensive patients may enable the clinician to better assess absolute CV risk, and its identification may induce physicians to encourage patients to make healthy lifestyle changes and perhaps would prompt to more aggressive modification of standard CV risk factors.

Identifying the determinants of microalbuminuria in obese patients in primary care units: the effects of blood pressure, random plasma glucose and other risk factors

OBJECTIVE

The objective of this study is to evaluate the demographic characteristics, blood pressure and blood glucose and the other related factors that affect the microalbuminuria levels in the obese patients aged 40 and above who applied to the primary care for medical evaluation.

MATERIALS AND METHODS

The population of the research, which was a cross-sectional type, comprised obese patients aged 40 and above who had applied to the community health centers in the center of Malatya. A total of 422 obese patients consisting of 116 males and 306 females were included in the research. The anthropometric measurements of the participants were determined, their blood pressures and their random blood glucoses were evaluated, as well. A microalbuminuria measurement was performed in the urine samples taken from the patients using "Nycocard Reader II" device.

FINDINGS

The incidence of microalbuminuria in patients was found as 31.5%, whereas the incidence of macroalbuminuria was 6.6%. The incidence of microalbuminuria in female patients was 32.7%, while it was 28.4% in male patients; on the other hand, the incidence of macroalbuminuria in female patients was found as 6.8%, whereas this percentage was determined as 7.8 in male patients (p > 0.05). The probability of the incidence of microalbuminuria increased 2.8 times more in those with the diastolic blood pressure of 90 mmHg and above when compared to those without it (GA: 1.79-4.56), whereas the incidence increased 3.2 times more in those with the random blood glucose of 200 mg/l and above (GA: 1.32-7.84) (p < 0.001). In our study, among the variables predicting the microalbuminuria in obese patients; the cutoff values of the diastolic and systolic blood pressures, the waist circumference were found as >85 mmHg; >130 mmHg; >141 mg/dl, respectively, in male patients and found as >85 mmHg, >114 cm, and 109 cm, respectively, in female patients. The sensitivity and specificity of the tests indicating the cutoff values showed significance (p < 0.05). There was no statistically significant relevance between the microalbumin levels of the obese patients via the anthropometric criteria, except for their waist circumference (p > 0.05).

RESULT

In this study, the blood pressure and blood glucose levels of the patients along with their waist circumference that indicated a central obesity were specified as the determinants of microalbuminuria. While the obese patients are being evaluated in terms of proteinuria, the cutoff values of these variables can be taken into consideration.

Microalbuminuria is a late event in patients with hypertension: Do we need a lower threshold?

Background

Microalbuminuria (MA) is a marker of vascular damage. However, many studies have observed an increased risk at lower levels of albuminuria than are currently used to define MA.

Aim

To verify early cardiovascular changes occurring before MA in hypertensive patients.

Materials and methods

One hundred and fifty hypertensive patients and 60 normotensive individuals were divided into normotensive individuals with normal left ventricular (LV) geometry (Group I), hypertensive patients with normal LV geometry (Group II), and hypertensive patients with abnormal LV geometry (Group III). The LV mass index, ambulatory arterial stiffness index, flow-mediated dilatation of the brachial artery, and intima-media thickness (IMT) of the common carotid were assessed. Urinary albumin/creatinine ratio was determined using a morning spot-urine sample.

Results

Compared with Group I, ambulatory arterial stiffness index and IMT were significantly increased and flow-mediated dilatation was significantly decreased in Group II; however, MA did not differ between both groups. These changes were augmented when Group III was compared with Group II. MA significantly increased in Group III compared with Group II. Receiver operating characteristic analysis revealed that MA, with a cut-off value of 19.25 mg/g, predicted increased IMT, and abnormal LV geometry in a statistically significant manner.

Conclusion

Many vascular changes, in the form of increased IMT, reduced vasodilator capacity, and increased arterial stiffness, preceded MA and any change in LV geometry. The results presented here strengthen the usefulness of adopting a lower cut-off to define MA.

Influence of chronic kidney disease on cardiac structure and function

Chronic kidney disease (CKD), the presence of kidney dysfunction and/or damage, is a worldwide public health issue. Although CKD is independently associated with various subtypes of cardiovascular diseases, a recent international collaborative meta-analysis demonstrates that CKD is particularly strongly associated with heart failure, suggesting its critical impact on cardiac structure and function. Although numerous studies have investigated the association of CKD and cardiac structure and function, these studies substantially vary regarding source populations and methodology (e.g., measures of CKD and/or parameters of cardiac structure and function), making it difficult to reach universal conclusions. Nevertheless, in this review, we comprehensively examine relevant studies, discuss potential mechanisms linking CKD to alteration of cardiac structure and function, and demonstrate clinical implications as well as potential future research directions. We exclusively focus on studies investigating both CKD measures, kidney function (i.e., glomerular filtration rate [GFR], creatinine clearance, or levels of filtration markers), and kidney damage represented by albuminuria, since current international clinical guidelines of CKD recommend staging CKD and assessing its clinical risk based on both GFR and albuminuria.

Presence of albuminuria predicts left ventricular mass in patients with chronic systemic arterial hypertension

BACKGROUND

Increased left ventricular mass (LVM) is known to predict cardiovascular morbidity and mortality. LVM is high in patients with advanced kidney disease. Our aim was to study the relationship between renal parameters and LVM in hypertensive subjects at high risk of cardiovascular disease.

DESIGN

Cardiac MRI was performed in 527 patients participating in the single-centre SMART cohort study. Participants free from previous symptomatic coronary heart disease but with a history of hypertension were recruited. Subjects were screened for cardiovascular risk factors in a standardized way. Multivariable linear regression was used to study the relationship of both estimated glomerular filtration rate (eGFR) and presence of albuminuria with left ventricular mass.

RESULTS

Mean LVM was 121 g for men (SD 26) and 87 g for women (SD 20). Mean eGFR was 82 mL/min/1.73 m(²) (SD 19). A total of 73 patients (14%) had albuminuria. After adjusting for known determinants of LVM (height, weight, sex and age) eGFR did not relate to LVM while presence of albuminuria did (mean change in LVM per 10 mL/min/1.73 m(2) change in eGFR 0.79 g, 95% CI -0.33 to 1.91, P = 0.17, mean change in LVM in presence vs. absence of albuminuria 9.9 g, 95% CI 4.33 to 15.45, P = 0.001). Additional adjustment for systolic blood pressure did not change results (B for eGFR 0.54, 95% CI -0.58 to 1.66, P = 0.35, B for albuminuria 9.09, 95% CI 3.57 to 14.60, P = 0.001).

CONCLUSIONS

In this study in hypertensive patients with high vascular risk, albuminuria was related to increased LVM and eGFR was not.

Prognostic Impact of Diabetes Mellitus in Chronic Heart Failure According to Presence of Ischemic Heart Disease – With Special Reference to Nephropathy

BACKGROUND

It is unclear whether the prognostic impact of diabetes mellitus (DM) in chronic heart failure (CHF) is influenced by ischemic heart disease (IHD) and/or nephropathy.

METHODS AND RESULTS

We enrolled 4,065 consecutive patients with stage C/D CHF (mean age, 69.0 years; 68.7% male) in the CHART-2 Study (n=10,219). We defined DM as current history of DM treatment or HbA1c ≥6.5% (National Glycohemoglobin Standardization Program [NGSP]), and nephropathy as urine albumin:creatinine ratio ≥30 mg/g or urine dipstick test ≥(±) at enrollment. Impacts of DM and nephropathy on the composite of death, myocardial infarction, stroke, and HF admission were examined. Among the 4,065 patients, 1,448 (35.6%) had DM, while IHD and nephropathy were also noted in 1,644 (40.4%) and in 1,549 (38.1%), respectively. During the median follow-up of 2.88 years, 1,025 (25.2%) reached the composite endpoint. On multivariate Cox regression, DM was significantly associated with the composite endpoint in all patients (HR, 1.17; P=0.02), and in those with IHD (HR, 1.38; P=0.004), but not in those without IHD (HR, 1.12; P=0.22; P for interaction=0.12). Furthermore, when the patients were stratified by nephropathy, DM was associated with worse prognosis only in the IHD patients with nephropathy.

CONCLUSIONS

The prognostic impact of DM was more evident in patients with IHD than in those without IHD, particularly when complicated with nephropathy.

Association between low-grade albuminuria and cardiovascular risk in Korean adults: the 2011-2012 Korea National Health and Nutrition Examination Survey

Background

Recent studies have indicated that low UACR levels (<30 μg/mg) previously considered to be in the normal range (‘low-grade albuminuria’) are associated with cardiovascular morbidity and mortality in the general population.

Methods

We studied 9,736 participants with albuminuria in the normal range from the 2011–2012 Korea National Health and Nutrition Examination Survey (KNHANES).

Results

The weighted prevalences of metabolic syndrome (MS) and the 10-year risk for coronary heart disease measured using the Framingham risk score (FRS) ≥ 20% (high risk) were 22.5 ± 0.7% and 14.5 ± 0.7%, respectively, in males and 23.3 ± 0.8% and 8.5 ± 0.4%, respectively in females. Weighted comparisons among the tertiles of UACR revealed that the prevalences of MS and high-risk FRS increased with increasing UACR (MS: males, 15.9 ± 1.1, 20.2 ± 1.2, 32.4 ± 1.5%, respectively; P < 0.001; and females, 17.6 ± 1.0, 22.7 ± 1.0, 30.2 ± 1.4%, respectively; P < 0.001. High-risk FRS: males, 9.5 ± 0.7, 12.3 ± 0.9, 22.5 ± 1.2, respectively; P < 0.001; and females, 5.8 ± 0.6, 7.9 ± 0.7, 12.0 ± 0.9%, respectively; P < 0.001). The positive association persisted after adjusting for hypertension and diabetes. The weighted comparisons among the deciles of UACR revealed that the prevalences of MS and high-risk FRS began to increase at the ranges of 3.89–5.15 and 5.16–7.36 mg/g Cr, respectively.

Conclusion

Low-grade albuminuria was significantly associated with estimated cardiovascular risk and MS in a nationally representative sample of Koreans.

Association between renal function and cardiovascular structure and function in heart failure with preserved ejection fraction

AIM

Renal dysfunction is a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). We sought to determine whether renal dysfunction was associated with measures of cardiovascular structure/function in patients with HFpEF.

METHODS

We studied 217 participants from the PARAMOUNT study with HFpEF who had echocardiography and measures of kidney function. We evaluated the relationships between renal dysfunction [estimated glomerular filtration rate (eGFR) >30 and <60 mL/min/1.73 m(2) and/or albuminuria] and cardiovascular structure/function.

RESULTS

The mean age of the study population was 71 years, 55% were women, 94% hypertensive, and 40% diabetic. Impairment of at least one parameter of kidney function was present in 62% of patients (16% only albuminuria, 23% only low eGFR, 23% both). Renal dysfunction was associated with abnormal LV geometry (defined as concentric hypertrophy, or eccentric hypertrophy, or concentric remodelling) (adjusted P = 0.048), lower midwall fractional shortening (MWFS) (P = 0.009), and higher NT-proBNP (P = 0.006). Compared with patients without renal dysfunction, those with low eGFR and no albuminuria had a higher prevalence of abnormal LV geometry (P = 0.032) and lower MWFS (P < 0.01), as opposed to those with only albuminuria. Conversely, albuminuria alone was associated with greater LV dimensions (P < 0.05). Patients with combined renal impairment had mixed abnormalities (higher LV wall thicknesses, NT-proBNP; lower MWFS).

CONCLUSION

Renal dysfunction, as determined by both eGFR and albuminuria, is highly prevalent in HFpEF, and associated with cardiac remodelling and subtle systolic dysfunction. The observed differences in cardiac structure/function between each type of renal damage suggest that both parameters of kidney function might play a distinct role in HFpEF.

Slight increase in urinary albumin excretion within the normal range predicts incident hypertension in a community-based Japanese population: the Takahata study

Recent studies have suggested that urine albumin excretion in the high normal range predicts hypertension. However, the relationship between urinary albumin excretion in spot urine and incident hypertension remains unclear in the general Japanese population. To clarify this relationship, we conducted a cohort study in a community-based population of 412 normotensive individuals without diabetes and renal insufficiency and examined the incidence of hypertension using the urinary albumin-to-creatinine ratio (UACR) at baseline. Incident hypertension was defined as new-onset systolic blood pressure ⩾ 140 mm Hg and/or diastolic blood pressure ⩾ 90 mm Hg and/or the use of anti-hypertensive drugs. During the follow-up period (median, 6.7 years), 133 subjects (32.3%) newly developed hypertension. The incidence of hypertension increased with an increase in baseline UACR (20.4% for UACR <5 mg g(-1), 34.0% for 5-9.9 mg g(-1) UACR and 40.4% for 10-29.9 mg g(-1), P=0.002). Multivariate logistic regression analysis, after adjustment for possible confounders, showed that UACR 5-9.9 mg g(-1) and 10-29.9 mg g(-1) were independent risks for incident hypertension compared with UACR <5 mg g(-1) (odds ratio (OR) 2.15, 95% confidence interval (CI) 1.16-4.10 and OR 2.67, 95% CI 1.36-5.38, respectively). Subgroup analysis revealed that subjects with increased UACR (⩾ 5 mg g(-1)) had a higher risk of incident hypertension than did those with low UACR (<5 mg g(-1)), irrespective of their backgrounds (age, sex, smoking, alcohol consumption, obesity and urinary sodium excretion). In conclusion, this study showed that a slight increase in urinary albumin excretion might predict incident hypertension in a community-based Japanese population.

Low-Grade Albuminuria Is Associated with Metabolic Syndrome and Its Components in Middle-Aged and Elderly Chinese Population

BACKGROUND

Micro-albuminuria has been well established as one of the risk factors of metabolic syndrome (MetS). However, the association of MetS and its components with low-grade albuminuria among those with normal urinary albumin excretion has not been clearly elucidated in Chinese population.

METHODOLOGY AND FINDINGS

A cross-sectional study was conducted among 9,579 participants with normal urinary albumin excretion, who were recruited from Jia Ding District, Shanghai, China. The single-void first morning urine sample was collected for urinary albumin and creatinine measurements, and urinary albumin-to-creatinine ratio (UACR) was calculated as urinary albumin divided by creatinine. Low-grade albuminuria was classified as sex-specific upper UACR quartile in this population. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. The prevalence of MetS and its components increased across the UACR quartiles (all P trend <0.01). A multivariable adjusted logistic regression analysis revealed that the prevalence of MetS was gradually elevated according to the UACR quartiles (adjusted odds ratios [ORs] were 1.14, 1.24 and 1.59 for UACR quartiles 2, 3 and 4, compared with the lowest quartile; P trend<0.0001). In the further stratified logistic regression analyses, the associations between low-grade albuminuria and MetS were significant in both sex strata (male and female), both age strata (<60 and ≥60 years), both body mass index strata (<24 and ≥24 kg/m(2)), and both diabetes strata (yes and no). Compared to the lowest UACR quartile, the participants in the highest quartile of UACR had the highest prevalence of central obesity (OR = 1.43; 95%CI = 1.25-1.63), high blood pressure (OR = 1.64; 95%CI = 1.43-1.87), hyperglycemia (OR = 1.52; 95%CI = 1.30-1.78) and high triglycerides (OR = 1.19; 95%CI = 1.04-1.37).

CONCLUSIONS AND SIGNIFICANCE

Low-grade albuminuria was significantly associated with the increasing prevalence of MetS and its components in the middle-aged and elderly Chinese population with normal urinary albumin excretion.

Association of heart rate and left ventricular structure in a rural population in Korea

Abstract We investigated the association of heart rate (HR) and estimated glomerular filtration rate (eGFR) with left ventricular (LV) structure in a multi-rural cohort project in Korea. A total of 3215 subjects were analyzed for factors related to Echo-LV mass index (LVMI). eGFR was positively associated with both types of LVMI whereas HR was negatively associated with both. Odd ratios (ORs) (highest versus lowest quartiles) for LVMI by height(2.7) were significant for HR (OR: 0.441, p = 0.0035 in males; OR: 0.638, p = 0.0226 in females), and for eGFR (OR:1.643, p = 0.0145) in females. In conclusion, in addition to age, systolic blood pressure and body mass index, eGFR is positively associated with echocardiographic LVMI and HR is negatively associated with echocardiographic LVMI.

Cardiac structure and function and renal insufficiency in the oldest old

BACKGROUND

People over the age of 85 years have a high incidence of cardiovascular disease and chronic kidney disease.

HYPOTHESIS

There is an association between renal function and cardiac structure and function in subjects 85 years of age.

METHODS

Subjects born in the years 1920 and 1921 were recruited from the Jerusalem Longitudinal Cohort Study. Echocardiography was performed at the subject's home with assessment of cardiac structure and function. Glomerular filtration rate (GFR) was assessed by the Cockroft-Gault formula, with abnormal GFR defined as ≤60 mL/min/1.73 m(2).

RESULTS

There were 310 subjects who were enrolled. When GFR was examined as a continuous variable, linear regression showed a small although statistically significant relationship between GFR and left atrial volume (r = 0.15, P < 0.014), left ventricular mass index (r = 0.12, P < 0.04), and ejection fraction (r = 0.19, P < 0.03) but not with indices of diastolic function (r = 0.02, P < 0.72). However, using the accepted clinical cutoff of 60 mL/min/1.73 m(2), there were no significant differences between subjects with normal and abnormal GFR in indices of cardiac structure. Ejection fraction (57.0 ± 10.4% vs 54.4 ± 10.3%; P = 0.08) and indices of diastolic function (E/e' 12.4 ± 5.0 vs 12.3 ± 4.6; P = 0.89) were not significantly different between the 2 groups.

CONCLUSIONS

A weak and clinically insignificant association was found between GFR as a continuous variable and indices of cardiac function. However, using the clinically accepted cutoff, no association between abnormal GFR and cardiac structure or function was observed.

Exposure to bisphenol A is associated with low-grade albuminuria in Chinese adults

Bisphenol A is an industrial chemical widely used in plastic products with a consequent exposure to humans. To assess whether exposure to bisphenol A is associated with renal disease, we searched for low-grade albuminuria in 3055 Chinese adults in the Shanghai metropolitan area aged 40 years or older. Using a value for urinary albumin-to-creatinine ratios <30 mg/g, we examined its association with urinary bisphenol A. Participants in the highest compared to the lowest quartile of urinary bisphenol A concentrations were significantly more likely to have low-grade albuminuria. Multivariate stepwise linear regression analysis, adjusted for potential confounding factors, showed that urinary bisphenol A was an independent determinant of the urinary albumin-to-creatinine ratio significantly associated with an increased risk of low-grade albuminuria with an adjusted odds ratio of 1.23 for the highest compared to the lowest concentration quartiles. This association was not modified by conventional risk factors such as age, gender, smoking, alcohol consumption, body mass index, hypertension, diabetes, and the estimated glomerular filtration rate. There was no significant relationship between bisphenol A and combined micro- and macroalbuminuria. Thus, our study lends support to a potential relation between bisphenol A exposure and an increased risk of low-grade albuminuria.

The relationship between renal impairment and left ventricular structure, function, and ventricular-arterial interaction in hypertension

OBJECTIVES

Our objective was to define the relationship between renal dysfunction--both albuminuria and reduced estimated glomerular filtration rate (eGFR)--and cardiac structure and diastolic dysfunction among patients with chronic hypertension.

METHODS

Both albuminuria and eGFR were measured in 540 asymptomatic patients with hypertension and diastolic dysfunction assessed by reduced early mitral annular relaxation velocity (E'). The majority of patients were white, mean age was 60 ± 10 years, mean SBP was 149 ± 18 mmHg, and there was a low prevalence comorbid conditions. Albuminuria was undetectable in 148 (27%), within the normal to low range [urine albumin-to-creatinine ratio (UACR) 1-25 mg/g for men, 1-17 mg/g for women] in 292 (54%), and high or very high (UACR >25 mg/g for men, >17 mg/g for women) in 100 (19%). Estimated GFR was 60 ml/min per 1.73 m² or less in 75 (14%), 61-90 ml/min per 1.73 m² in 244 (45%), and more than 90 ml/min per 1.73 m² in 221 (41%).

RESULTS

Albuminuria, even within the normal range, was associated with greater left ventricular wall thickness (P = 0.01), higher relative wall thickness (P = 0.004), worse diastolic function reflected in lower E' (P = 0.01), greater arterial and left ventricular end-systolic stiffness (P < 0.0001 and P = 0.003, respectively), and higher N-terminal pro-brain natriuretic peptide (NT-proBNP) level (P = 0.0025), even after adjustment for differences in baseline characteristics. In contrast, no independent relationship was observed between eGFR and parameters of cardiac structure or function.

CONCLUSION

Among asymptomatic hypertensive patients with evidence of diastolic dysfunction, the presence of albuminuria, even within the normal range, is associated with greater concentric remodeling, greater left ventricular end-systolic stiffness, and worse diastolic function.

High-normal albuminuria and risk of heart failure in the community

BACKGROUND

Albuminuria has been associated with cardiovascular risk, but the relationship of high-normal albuminuria to subsequent heart failure has not been well established.

STUDY DESIGN

Prospective observational study, the Atherosclerosis Risk in Communities (ARIC) Study.

SETTING & PARTICIPANTS

10,975 individuals free from heart failure were followed up from the fourth ARIC Study visit (1996-1998) through January 2006.

PREDICTOR

Urinary albumin-creatinine ratio (UACR), analyzed continuously and categorically as optimal (<5 mg/g), intermediate-normal (5-9 mg/g), high-normal (10-29 mg/g), microalbuminuria (30-299 mg/g), and macroalbuminuria (≥300 mg/g).

OUTCOMES & MEASUREMENTS

Incident heart failure was defined as a heart failure-related hospitalization or death. Cox proportional hazard models were used to calculate the HR of heart failure after adjustment for age, race, sex, estimated glomerular filtration rate (eGFR), and other cardiovascular risk factors.

RESULTS

Individuals were followed up for a median of 8.3 years and experienced 344 heart failure events. Compared with normal UACR, albuminuria was associated with a progressively increased risk of heart failure from intermediate-normal (adjusted HR, 1.54; 95% CI, 1.12-2.11) and high-normal UACR (adjusted HR, 1.91; 95% CI, 1.38-2.66) to microalbuminuria (adjusted HR, 2.49; 95% CI, 1.77-3.50) and macroalbuminuria (adjusted HR, 3.47; 95% CI, 2.10-5.72). Results were similar in secondary analyses of participants censored at the time of coronary heart disease event and along a range of eGFRs.

LIMITATIONS

UACR was measured as a single random sample.

CONCLUSIONS

Albuminuria is associated with subsequent heart failure, even in individuals with few cardiovascular risk factors and UACR within the normal range. Our results suggest that the association between albuminuria and heart failure may not be mediated fully by ischemic heart disease or kidney disease, measured using eGFR.

CUBN is a gene locus for albuminuria

Identification of genetic risk factors for albuminuria may alter strategies for early prevention of CKD progression, particularly among patients with diabetes. Little is known about the influence of common genetic variants on albuminuria in both general and diabetic populations. We performed a meta-analysis of data from 63,153 individuals of European ancestry with genotype information from genome-wide association studies (CKDGen Consortium) and from a large candidate gene study (CARe Consortium) to identify susceptibility loci for the quantitative trait urinary albumin-to-creatinine ratio (UACR) and the clinical diagnosis microalbuminuria. We identified an association between a missense variant (I2984V) in the CUBN gene, which encodes cubilin, and both UACR (P = 1.1 × 10(-11)) and microalbuminuria (P = 0.001). We observed similar associations among 6981 African Americans in the CARe Consortium. The associations between this variant and both UACR and microalbuminuria were significant in individuals of European ancestry regardless of diabetes status. Finally, this variant associated with a 41% increased risk for the development of persistent microalbuminuria during 20 years of follow-up among 1304 participants with type 1 diabetes in the prospective DCCT/EDIC Study. In summary, we identified a missense CUBN variant that associates with levels of albuminuria in both the general population and in individuals with diabetes.

Obstructive sleep apnea: a stand-alone risk factor for chronic kidney disease

BACKGROUND

Previous studies have found an association between obstructive sleep apnea (OSA) and chronic kidney disease (CKD). However, subjects with confounding factors such as diabetes and hypertension were not excluded. The purpose of the present study was to determine whether patients with OSA without meeting criteria for diabetes or hypertension would also show increased likelihood of CKD.

METHODS

We prospectively enrolled adult patients with a chief complaint of habitual snoring. Overnight polysomnography, fasting blood triglyceride, cholesterol, glucose, insulin, creatinine, albumin and hemoglobin A1c, and first voiding urine albumin and creatinine were examined. Estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR), homeostatic model assessment-insulin resistance and percentage of CKD were calculated.

RESULTS

The final analyses involved 40 patients who were middle-aged [44.8 (8.6) years] predominantly male (83%), obese [body mass index, 28.2 (5.1) kg/m(2)] and more severe OSA, with an apnea-hypopnea index (AHI) of 51.6 (39.2)/h. The mean eGFR and UACR were 85.4 (18.3) mL/min/1.73m(2) and 13.4 (23.4) mg/g, respectively. The prevalence of CKD in severe OSA subjects is 18%. With stepwise multivariate linear regression analysis, AHI and desaturation index were the only independent predictor of UACR (β = 0.26, P = 0.01, R(2) = 0.17) and eGFR (β = 0.32, P < 0.01, R(2) = 0.32), respectively.

CONCLUSIONS

High prevalence of CKD is present in severe OSA patients without hypertension or diabetes. Significantly positive correlations were found between severity of OSA and renal function impairment.