Microalbuminuria predicts cardiovascular events and renal insufficiency in patients with essential hypertension

Clinical guidelines for the diagnosis, evaluation, and management of hypertension for Korean children and adolescents: the Korean Working Group of Pediatric Hypertension

Pediatric hypertension (HTN) is a significant, growing health concern worldwide and also in Korea. Diagnosis, evaluation, and treatment of HTN in Korean children and adolescents are uncertain due to limitations in using the current international guidelines, since the recommendations by the American Academy of Pediatrics (AAP) and European Society of Hypertension (ESH) guidelines differ. Furthermore, these are guidelines for Western youth, who are racially and ethnically different from Koreans. In addition, reference blood pressure values for all pediatric age groups, which are essential for the diagnosis of HTN according to these two guidelines, are absent in Korea. Therefore, HTN guidelines for Korean children and adolescents should be established. The Korean Working Group of Pediatric Hypertension established clinical guidelines for the diagnosis, evaluation, and management of HTN in Korean children and adolescents. These guidelines were based on reported clinical evidence, expert recommendations, and AAP and ESH guidelines. The characteristics of Korean youth and the Korean medical and insurance system were considered during the establishment of the guidelines. By providing recommendations suitable for Korean youth, these guidelines will help in the prevention and management of childhood HTN, thus relieving the burden of cardiovascular disease in adulthood in Korea.

[Prognostic Value of Isolated High Serum Cystatin C Levels Without Glomerular Filtration Rate Reduction]

OBJECTIVES

Cystatin C is increasingly used as a marker of renal function as a complement to serum creatinine and glomerular filtration rate (GFR). We have assessed its efficacy as a predictor of mortality in a group of patients with increased cystatin C but GFR> 60mL/min.

DESIGN AND METHODS

We included 608 patients, 65.9% male, 34.6% had diabetes mellitus. The mean age was 58.5±14.5 years and a mean GFR of 64.1±33.5mL/min. Patients were divided into 3 groups: CONTROL (normal cystatin C and GFR> 60mL/min, age 53.3±12.8years, GFR 96.6±22.4mL/min,n=193), INCREASED CYSTATIN (cystatin C>1.03mg/l and GFR>60mL/min, age 58.9±13,1years, GFR 72.2±10.4mL/min, n=40) and CKD (chronic kidney disease, increased cystatin C and GFR <60mL/min, age 61.4±14.8years, GFR 36.0±12.7mL/min, n=160). The relationship with overall mortality was analyzed using the Kaplan-Meier method.

RESULTS

Mean cystatin C was 0.75±0.13 versus 1.79±0.54 in CKD group and 1.14±0.14mg/l, p <0.001). In CONTROL group survival was 93.9% at 5y, compared to 78.8% in the ERC group and 82.3% in the INCREASED CYSTATIN group (p <0.001) Five-year survival before renal replacement therapy was also different for the ERC group (73%, p <0.001 Log Rank) but not between the other two groups (CONTROL 99.0%, INCREASED CYSTATIN 94.3% p=0.08).

CONCLUSIONS

Increased plasmatic levels of cystatin C in patients with GFR> 60mL/min was a predictor of increased mortality but not of progression to end-stage renal failure. These results confirm the interest of routinely measuring cystatin C.

Microalbuminuria and mortality in individuals with coronary heart disease: A meta-analysis of a prospective study

AIM

Microalbuminuria has been elevated as an outcome predictor in cardiovascular medicine. However, due to the small number of studies investigating the association of microalbuminuria and mortality in the coronary heart disease (CHD) population, the prognosis value of microalbuminuria in CHD remains under debate. The objective of this meta-analysis was to investigate the relationship between microalbuminuria and mortality in individuals with CHD.

METHOD

A comprehensive literature search was performed using Pubmed, EuroPMC, Science Direct, and Google Scholar from 2000 to September 2022. Only prospective studies investigating microalbuminuria and mortality in CHD patients were selected. The pooled effect estimate was reported as risk ratio (RR).

RESULTS

5176 patients from eight prospective observational studies were included in this meta-analysis. Individuals with CHD have a greater overall risk of all-cause mortality (ACM) [rR = 2.07 (95% CI = 1.70-2.44); p = 0.0003; I2 = 0.0%] as well as cardiovascular mortality (CVM) [rR = 3.23 (95% CI = 2.06-4.39), p < 0.0001; I2 = 0.0%]. Subgroup analysis based on follow-up duration and a subset of CHD patients were similarly associated with an increased risk of ACM.

CONCLUSION

This meta-analysis indicates that microalbuminuria is associated with a higher risk of mortality in individuals with CHD. Microalbuminuria can serve as a predictor of poor outcomes in CHD patients.

Correlates of Hypertensive-Level BP in African American Adolescents

OBJECTIVE

Adult cardiovascular disease has its roots in childhood and adolescence. Risks for pediatric hypertension include obesity, male sex, and minority race. We identified risk factors associated with hypertension specifically among African American adolescents ages 13-18.

METHODS

We analyzed data from the US National Health and Nutrition Examination Surveys from 2011 to 2018, defining BP consistent with hypertension as average systolic or diastolic BP ≥ 130/80 mmHg or taking medication for a clinical diagnosis of hypertension. Univariate analyses compared characteristics of adolescents with and without hypertensive-level BP. Logistic regression was completed to more precisely identify risk factors.

RESULTS

Among 838 African American adolescents, 48 met criteria for hypertensive-level BP, for a population prevalence of 5.8%. Due to low rates of hypertensive-level BP in girls (2.7%), our analysis focused on the subset of boys, who had an 8.9% prevalence rate, increasing to 26.1% for boys with obesity and 35.3% for boys with severe obesity. Boys with hypertensive-level BP had significantly lower family incomes, higher rates of being in single-parent families, more frequent consumption of fast food, were more likely to be taking prescription medications for psychiatric diagnoses, and had higher A1c and cholesterol values.

CONCLUSIONS

Our study confirms the much higher risk for hypertensive-level BP in African American boys and emphasizes the important role of social determinants of health in this common illness.

From Structural to Functional Hypertension Mediated Target Organ Damage—A Long Way to Heart Failure with Preserved Ejection Fraction

Arterial hypertension (AH) is a major risk factor for the development of heart failure (HF) which represents one of the leading causes of mortality and morbidity worldwide. The chronic hemodynamic overload induced by AH is responsible for different types of functional and morphological adaptation of the cardiovascular system, defined as hypertensive mediated target organ damage (HMOD), whose identification is of fundamental importance for diagnostic and prognostic purposes. Among HMODs, left ventricular hypertrophy (LVH), coronary microvascular dysfunction (CMVD), and subclinical systolic dysfunction have been shown to play a role in the pathogenesis of HF and represent promising therapeutic targets. Furthermore, LVH represents a strong predictor of cardiovascular events in hypertensive patients, influencing per se the development of CMVD and systolic dysfunction. Clinical evidence suggests considering LVH as a diagnostic marker for HF with preserved ejection fraction (HFpEF). Several studies have also shown that microalbuminuria, a parameter of abnormal renal function, is implicated in the development of HFpEF and in predicting the prognosis of patients with HF. The present review highlights recent evidence on the main HMOD, focusing in particular on LVH, CMD, subclinical systolic dysfunction, and microalbuminuria leading to HFpEF.

Hypertension-mediated organ damage in masked hypertension

OBJECTIVES

Masked hypertension - a blood pressure (BP) phenotype characterized by a clinic BP in the normal range but elevated BP outside the office - is associated with early hypertension-mediated organ damage. This study examined early target organ manifestations of masked hypertension diagnosed by home (HBPM) and ambulatory (ABPM) BP monitoring.

METHODS

Left ventricular (LV) structure and diastolic function measured by echocardiography, microalbuminuria, and coronary artery calcification were evaluated in 420 patients with high clinic BP (SBP 120-150 mmHg or DBP 80-95 mmHg). Evidence of hypertension-mediated organ damage was compared in patients with sustained normotension, masked hypertension, and sustained hypertension based on measurements by HBPM, daytime ABPM, and 24-h ABPM.

RESULTS

The 420 participants averaged 48 (12) [mean (SD)] years of age; the average clinic BP was 130 (13)/81 (8) mmHg. In individuals with masked hypertension diagnosed by HBPM, indexed LV mass, relative wall thickness, and e' and E/e' (indices of LV relaxation), were generally intermediate between values observed in normotensives and sustained hypertensive patients, and were significantly greater in masked hypertension than normotensives. Similar trends were observed when masked hypertension was diagnosed by ABPM but a diagnosis of masked hypertension was not as reliably associated with LV remodeling or impaired LV relaxation in comparison to normotensives. There were trends towards greater likelihoods of detectable urinary microalbumin and coronary calcification in masked hypertension than in normotensives.

CONCLUSION

These results support previous studies demonstrating early hypertension-mediated organ damage in patients with masked hypertension, and suggest that HBPM may be superior to ABPM in identifying patients with masked hypertension who have early LV remodeling and diastolic LV dysfunction.

Utility of urinary albumin excretion as an index for stratifying the residual cardiovascular risk in patients undergoing antihypertensive agents treatment

BACKGROUND

Patients treated with antihypertensive medication, even those with well controlled blood pressure (BP), are at higher risk for the development of atherosclerotic cardiovascular disease (ASCVD) in comparison to nonhypertensive individuals with optimal risk levels. We hypothesized that this residual risk could be stratified based on urinary albumin excretion (UAE).

METHODS

A total of 13 082 middle-aged and older individuals with SBP/DBP of less than 160/100 mmHg and urinary albumin-to-creatinine ratios (UACRs) of less than 300 mg/g, and who were free from ASCVD events, were followed to investigate the incidence of ASCVD. The baseline BP was classified into four categories: normal BP (BP1), high normal BP (BP2), elevated BP (BP3), and grade 1 hypertension (BP4) based on the 2019 Japanese Society of Hypertension guidelines.

RESULTS

After an average 10.6 ± 2.6 years of follow-up, the multivariable hazard ratio for the development of ASCVD (n = 994) was already increased in medicated hypertensive patients with BP1 in comparison with untreated individuals with BP1; however, among medicated hypertensive patients, this risk was separated between the UAE groups, which were classified according to the median UACR (male, 15.4 mg/g; female, 19.0 mg/g). In medicated hypertensive patients with any category of BP1-BP3, the adjusted risk of the development of ASCVD in those with lower and higher UACRs was comparable to that observed in untreated individuals in the BP1 and BP4 categories, respectively.

CONCLUSION

In medicated patients with well controlled hypertension, UAE is useful for stratifying the residual risk of developing ASCVD in comparison to nonhypertensive individuals with optimal risk levels.

Relationship between 25-hydroxyvitamin D and microalbuminuria in patients with newly diagnosed essential hypertension

Purpose: Vitamin D deficiency is known that associated with hypertension. Microalbuminuria (MAU) is associated with increased cardiovascular morbidity and mortality. This study aimed to evaluate the relationship between 25-hydroxyvitamin D (25(OH)D) and MAU in newly diagnosed essential hypertension (NDEH) patients. Methods: A total of 116 patients with a diagnosis of NDEH were enrolled in the study. The diagnosis of hypertension was based on ABPM. Patients were divided into 2 groups according to 25(OH)D levels: Group 1: (25(OH)D)>20 ng/mL was defined as Vitamin D sufficiently (VDS), while Group 2: (25(OH)D)<20 ng/mL was defined Vitamin D deficiently (VDD). The relationship between 25(OH)D and MAU was analyzed. The results were analyzed using the SPSS program version 21. Results: The mean age of the patients was 58.4 ± 14.7 years and 60 (51.7%) of them were female. The prevalence of MAU was 18.9% and Vitamin D deficiency was 61.2% in NDEH. Linear regression analysis showed that 25(OH)D was independently related to MAU [β 0.643, 95% confidence interval 1.173-1.631, p = .011]. Besides, male gender, C-reactive protein, non-dipper hypertension, and diastolic blood pressure were independent risk factors associated with MAU in the multivariate analysis (p < .05). Conclusion: Vitamin D deficiency is highly prevalent in NDEH patients. This study showed that the level of microalbuminuria was significantly higher in patients with 25(OH)D deficiency compared to patients with normal 25(OH)D levels. Vitamin D deficiency is independently related to microalbuminuria in NDEH.

Effects of inhibition of the renin-angiotensin system on hypertension-induced target organ damage: clinical and experimental evidence

The dysregulation of renin-angiotensin-system (RAS) plays a pivotal role in hypertension and in the development of the related target organ damage (TOD). The main goal of treating hypertension is represented by the long-term reduction of cardiovascular (CV) risk. RAS inhibition either by angiotensin converting enzyme (ACE)-inhibitors or by type 1 Angiotensin II receptors blockers (ARBs), reduce the incidence of CV events in hypertensive patients. Actually, ACE-inhibitors and ARBs have been demonstrated to be effective to prevent, or delay TOD like left ventricular hypertrophy, chronic kidney disease, and atherosclerosis. The beneficial effects of RAS blockers on clinical outcome of hypertensive patients are due to the key role of angiotensin II in the pathogenesis of TOD. In particular, Angiotensin II through an inflammatory-mediated mechanism plays a role in the initiation, progression and vulnerability of atherosclerotic plaque. In addition, Angiotensin II can be considered the hormonal transductor of the pressure overload in cardiac myocytes, and through an autocrine-paracrine mechanism plays a role in the development of left ventricular hypertrophy. Angiotensin II by modulating the redox status and the immune system participates to the development of chronic kidney disease. The RAS blocker should be considered the first therapeutic option in patients with hypertension, even if ACE-inhibitors and ARBs have different impact on CV prevention. ARBs seem to have greater neuro-protective effects, while ACE-inhibitors have greater cardio-protective action.

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.

Prevalence of Albuminuria in Cardiology and Endocrinology Departments and Its Influencing Factors: A Multicenter, Real-World Evidence Study in China

AIMS

To evaluate the prevalence of albuminuria and compare its risk factors in diabetic and hypertensive patients.

METHODS

This was an observational, cross-sectional, multicenter registry across China. Consecutive patients were registered with the Cardiology and Endocrine departments in 40 centers. Clinical characteristics were collected, and urinary albumin-to-creatinine ratio (UACR) was measured using the immunochemical method.

RESULTS

Of the 2510 patients enrolled in the study, 1515 underwent UACR testing and were included in the present analysis. The prevalence of microalbuminuria was 13.0% and 16.1% while that of macroalbuminuria was 2.5% and 5.0%, in the Cardiology and Endocrinology departments, respectively. HbA1c and systolic blood pressure (SBP) were independent risk factors for albuminuria. The relationship of blood pressure (BP) and HbA1c with albuminuria was continuous and graded. Compared with the reference level of SBP 130-139 mm Hg, an SBP level of <130 mmHg was significantly associated with a lower risk of albuminuria in all subjects (OR = 0.60; 95% CI: 0.40-0.89; P < 0.001) and in subjects with concomitant hypertension and diabetes (OR = 0.48; 95% CI: 0.25-0.92; P < 0.001).

CONCLUSIONS

In China, nearly one-fifth of patients in the Cardiology and Endocrinology departments have albuminuria although ACEI/ARB were widely used. More effective therapy is needed in this population.

Low-Grade Albuminuria Is Associated with Left Ventricular Hypertrophy and Diastolic Dysfunction in Patients with Hypertension

INTRODUCTION

Microalbuminuria is a risk factor for cardiovascular morbidity and mortality in hypertensive patients. However, the relationship between low-grade albuminuria, a higher level of albuminuria below microalbuminuria threshold, and hypertension-related organ damage is unclear. Left ventricular (LV) hypertrophy (LVH) is well recognized to be a subclinical organ damage of hypertension, and LV diastolic dysfunction is also reported to be an early functional cardiac change of hypertension that predicts heart failure. The present study aimed to investigate the association of low-grade albuminuria with LVH and LV diastolic dysfunction in hypertensive patients.

METHODS

This cross-sectional observational clinical study was retrospectively performed in 870 hypertensive patients admitted to our hospital. Urinary albumin to creatinine ratio (UACR) was calculated to assess the levels of albuminuria: macroalbuminuria (≥300 mg/g), microalbuminuria (≥30 mg/g, but <300 mg/g), and normal albuminuria (<30 mg/g). Low-grade albuminuria was defined as sex-specific highest tertile within normal albuminuria (8.1-29.6 mg/g in males and 11.8-28.9 mg/g in females). LVH and LV diastolic dysfunction were identified as recommended by American Society of Echocardiography.

RESULTS

Of the 870 patients, 765 (87.9%) had normal albuminuria, 77 (8.9%) had microalbuminuria, and 28 (3.2%) had macroalbuminuria. Percentage of LVH and LV diastolic dysfunction was increased with ascending UACR. UACR was independently associated with LVH and LV diastolic dysfunction, even in patients with normal albuminuria. Multivariable logistic regression showed that the patients with the highest tertile within normal albuminuria had nearly 80% increase in LVH and nearly 60% increase in LV diastolic dysfunction (adjusted OR for LVH 1.788, 95% CI 1.181-2.708, p = 0.006; adjusted OR for LV diastolic dysfunction 1.567, 95% CI 1.036-2.397, p = 0.034). After further stratification analyses in patients with normal albuminuria, it was shown that this independent association persisted in female patients, those who were younger than 70 years old, and those with duration of hypertension <15 years.

CONCLUSION

Low-grade albuminuria was associated with LVH and LV diastolic dysfunction in hypertensive patients, especially in patients younger than 70 years old, and those with duration of hypertension <15 years.

Immune-unreactive urinary albumin as a predictor of cardiovascular events: the Hortega Study

BACKGROUND

We aimed to determine if immune-unreactive albumin excretion (IURAE) is associated with cardiovascular (CV) events in a representative sample of a general population from Spain.

METHODS

We included 1297 subjects (mean age ± standard error 48.0 ± 0.2 years, 48% females), who participated in the Hortega Follow-Up Study. The primary endpoint was incidence of fatal and non-fatal CV events. Urinary albumin excretion (UAE) was measured in spot voided urine, frozen at -80°C, by immunonephelometry [immune-reactive albumin excretion (IRAE)] and by high-performance liquid chromatography (HPLC) [total albumin excretion (AE)]. IURAE was calculated as the difference between HPLC measurements and IRAE. We estimated fully adjusted hazard ratios (HRs) of CV incidence by Cox regression for IRAE, IURAE and total AE.

RESULTS

After an average at-risk follow-up of 13 years, we observed 172 CV events. urinary albumin to creatinine ratio (UACR) of ≥30 mg/g assessed by IRAE, IURAE or total AE concentrations was observed in 74, 273 and 417 participants, respectively. Among discordant pairs, there were 49 events in those classified as micro- and macroalbuminuric by IURAE, but normoalbuminuric by IRAE. Only the IRAE was a significant independent factor for the incidence of CV events [HR (95% confidence interval) 1.15 (1.04-1.27)]. The association of UAE with CV events was mainly driven by heart failure (HF) [HR 1.33 (1.15-1.55) for IRAE; HR 1.38 (1.06-1.79) for IURAE; HR 1.62 (1.22-2.13) for total AE]. Those subjects who were micro- and macroalbuminuric by both IRAE and IURAE had a significant increase in risk for any CV event, and especially for HF.

CONCLUSIONS

IRAE, IURAE and AE were associated with an increased risk for CV events, but IRAE offered better prognostic assessment.

New Areas of Interest: Is There a Role for Omega-3 Fatty Acid Supplementation in Patients With Diabetes and Cardiovascular Disease?

PURPOSE OF REVIEW

Summarize studies on omega-3 fatty acids in prevention of albuminuria in subjects with diabetes.

RECENT FINDINGS

Several small, short-term trials suggested benefit on albuminuria in subjects with diabetes; however, results were not definitive. Welty et al. showed that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for 1 year slowed progression of early-stage albuminuria in subjects with diabetes with clinical coronary artery disease on an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker, the majority of whom had an albumin/creatinine ratio (ACR) < 30 μg/mg. Moreover, significantly more (3-fold) subjects on EPA and DHA had a decrease in ACR compared to control, and three on EPA and DHA had a change in category from > 30 μg/mg to < 30 μg/mg, whereas no controls did. Potential mechanisms for benefit are discussed. These results suggest that there is benefit and perhaps even reversal of albuminuria with EPA and DHA at an early stage of disease in those with ACR < 30 μg/mg and those with microalbuminuria (ACR > 30).

microRNA-21 and hypertension

Hypertension, a multifactorial disease, is a major risk factor for the development of stroke, coronary artery disease, heart failure, and chronic renal failure. However, its underlying cellular and molecular mechanisms remain largely elusive. Numerous studies have shown that microRNAs (miRNAs) are involved in a variety of cellular processes, including cellular proliferation, apoptosis, differentiation, and the development of diseases. microRNA-21 (miR-21), a conserved single-stranded non-coding RNA that is composed of approximately 22 nucleotides, is one of the most intensively studied miRNAs in recent years, and it can regulate gene expression at the post-transcriptional level. miR-21 is expressed in many kinds of tumors and in the cardiovascular system, and it plays an important role in the occurrence and development of cardiovascular diseases. In recent years, more and more evidence indicates that miR-21 plays an important role in hypertension. This article reviews the source, function, and altered levels of miR-21 in hypertension and the role of miR-21 in the pathogenesis of hypertension and target organ damage (TOD). The potential role of miR-21 as a new target for predicting and treating hypertension is also explored.

Interaction between Albuminuria and Treatment Group Outcomes for Patients with Renal Artery Stenosis: The NITER Study

PURPOSE

To perform a post-hoc analysis of the Nephropathy Ischemic Therapy (NITER) trial, which enrolled patients with atherosclerotic renal artery stenosis, to evaluate whether medical therapy plus stent placement is superior to medical therapy alone in patients without elevated albuminuria.

MATERIALS AND METHODS

Data from 51 patients were analyzed and stratified into 2 cohorts by median urinary albumin (UAlb) levels: cohort 1 ("low albuminuria," UAlb ≤0.04 g/24h) and cohort 2 ("high albuminuria," UAlb >0.04g/24h). Interaction effect between treatment arms and UAlb cohorts was calculated using Cox regression analysis. Survival analysis was followed by test for effect size, power analysis, and construction of a Kaplan-Meier survival table.

RESULTS

At study completion, 13 patients had an outcome event: 6 (23%) from cohort 1 and 7 (28%) from cohort 2. Patients in cohort 1 had event-free survival of 83% at 3.9 ± 0.3 years from the primary endpoints of all-cause mortality, dialysis, and cardiovascular events when treated with interventional therapy, compared to 45% when treated with medical therapy alone (P = .501), which showed a 62% treatment effect for stent placement. In cohort 2, event-free survival rates were 64% for medical therapy versus 52% for medical plus interventional therapy (P = .64). Using Cox regression analysis, the interaction effect between treatment arms and UAlb cohorts was not significant (P = .32). The power of the study to detect an interaction effect, if one existed, was only 15%.

CONCLUSIONS

Inference cannot be drawn for similar populations because of inadequate sample size, but, in this sample, patients treated with stent placement who had low albuminuria had better outcomes than patients treated with medical therapy alone.

Association of Heart Rate Recovery With Microalbuminuria in Non-Obstructive Coronary Artery Disease

Background

Non-obstructive coronary artery disease (CAD) is associated with significantly increased risk for myocardial infarction. Heart rate recovery (HRR), a measure of autonomic function, is a strong predictor of all-cause mortality. Microalbuminuria, a marker of early arterial disease, is an independent risk factor for cardiovascular disease and mortality. We aimed to investigate HRR and determine its relationship with microalbuminuria in patients with non-obstructive CAD.

Methods

We prospectively studied 565 patients who underwent elective coronary angiography. All participants underwent urinary analysis and then an exercise test. Microalbuminuria was defined as an urinary albumin-to-creatinine ratio (UACR) of 30 - 299 mg/g. The HRR was abnormal if ≤ 12 beats/min during the first minute after exercise. First, all patients were divided into two groups, patients with microalbuminuria (n = 152) and patients without microalbuminuria (n = 413). Then, all patients were re-divided into two groups, those with lower HRR (≤ 12 beats/min, n = 126) and those with higher HRR (> 12 beats/min, n = 439).

Results

Patients with microalbuminuria had lower HRR and patients with lower HRR had higher UACR. While UACR was negatively correlated with HRR in patients with microalbuminuria (r = -0.424; P < 0.001) and in patients with lower HRR (r = -0.192; P= 0.042), there was no correlation of UACR with HRR in neither patients with normoalbuminuria nor patients with higher HRR, respectively. In the all study population, there was a significant inverse association between UACR and HRR (r = -0.445, P < 0.001), and UACR independently predicted the presence of lower HRR (P < 0.001).

Conclusions

Our findings showed that there was a significant inverse association between UACR and HRR in patients especially with microalbuminuria, and that albuminuria might predict cardiac autonomic imbalance evaluated by HRR in patients with non-obstructive CAD.

Microalbuminuria: Correlation With Prevalence and Severity of Coronary Artery Disease in Non-Diabetics

BACKGROUND

Previous studies have shown that microalbuminuria (MAU) is an independent risk factor for cardiovascular diseases in diabetics, hypertensive patients and in the general population. However, the correlation of MAU with the severity of coronary artery disease (CAD) in non-diabetic patients has not been addressed in detail. This study aimed to investigate the relationship between MAU and severity of angiographically confirmed CAD in non-diabetic patients.

METHODS

This was a cross-sectional study, which included 90 non-diabetic patients with documented CAD by coronary angiography. The ratio of urine albumin to creatinine was used to define MAU and severity of CAD was estimated using SYNTAX score. Patients were divided into two groups: group I that included patients without MAU and group II that included patients with MAU.

RESULTS

Out of 90 non-diabetic CAD patients, 62 (68.9%) were in group I (MAU negative) and 28 (31.1%) were in group II (MAU positive). There was statistically significant difference in the median SYNTAX score between the groups (21 vs. 28, P < 0.001). The prevalences of double vessel CAD and triple vessel CAD were significantly higher in MAU positive group. There was a strong relationship between the presence of MAU and the extent and complexity of CAD (r = 0.094; P < 0.001).

CONCLUSION

Thus, we conclude that patients with MAU have more severe angiographically detected CAD than those without MAU, and MAU exhibits a significant association with the presence and severity of CAD.

Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents

These pediatric hypertension guidelines are an update to the 2004 "Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents." Significant changes in these guidelines include (1) the replacement of the term "prehypertension" with the term "elevated blood pressure," (2) new normative pediatric blood pressure (BP) tables based on normal-weight children, (3) a simplified screening table for identifying BPs needing further evaluation, (4) a simplified BP classification in adolescents ≥13 years of age that aligns with the forthcoming American Heart Association and American College of Cardiology adult BP guidelines, (5) a more limited recommendation to perform screening BP measurements only at preventive care visits, (6) streamlined recommendations on the initial evaluation and management of abnormal BPs, (7) an expanded role for ambulatory BP monitoring in the diagnosis and management of pediatric hypertension, and (8) revised recommendations on when to perform echocardiography in the evaluation of newly diagnosed hypertensive pediatric patients (generally only before medication initiation), along with a revised definition of left ventricular hypertrophy. These guidelines include 30 Key Action Statements and 27 additional recommendations derived from a comprehensive review of almost 15 000 published articles between January 2004 and July 2016. Each Key Action Statement includes level of evidence, benefit-harm relationship, and strength of recommendation. This clinical practice guideline, endorsed by the American Heart Association, is intended to foster a patient- and family-centered approach to care, reduce unnecessary and costly medical interventions, improve patient diagnoses and outcomes, support implementation, and provide direction for future research.

Eicosapentaenoic and Docosahexaenoic Acids Attenuate Progression of Albuminuria in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease

Background

Albuminuria is a marker of inflammation and an independent predictor of cardiovascular morbidity and mortality. The current study evaluated whether eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation attenuates progression of albuminuria in subjects with coronary artery disease.

Methods and Results

Two‐hundred sixty‐two subjects with stable coronary artery disease were randomized to either Lovaza (1.86 g of EPA and 1.5 g of DHA daily) or no Lovaza (control) for 1 year. Percent change in urine albumin‐to‐creatinine ratio (ACR) was compared. Mean (SD) age was 63.3 (7.6) years; 17% were women and 30% had type 2 diabetes mellitus. In nondiabetic subjects, no change in urine ACR occurred in either the Lovaza or control groups. In contrast, ACR increased 72.3% (P<0.001) in diabetic subjects not receiving Lovaza, whereas those receiving Lovaza had no change. In diabetic subjects on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker, those receiving Lovaza had no change in urine ACR, whereas those not receiving Lovaza had a 64.2% increase (P<0.001). Change in ACR was directly correlated with change in systolic blood pressure (r=0.394, P=0.01).

Conclusions

EPA and DHA supplementation attenuated progression of albuminuria in subjects with type 2 diabetes mellitus and coronary artery disease, most of whom were on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker. Thus, EPA and DHA supplementation should be considered as additional therapy to an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker in subjects with type 2 diabetes mellitus and coronary artery disease.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01624727.

Pediatric Hypertension: Provider Perspectives

Pediatric hypertension is a risk for adult cardiovascular disease, making early detection important. The prevalence of pediatric essential hypertension is rising due to the increased prevalence of obesity. Though guidelines for screening, diagnosis, evaluation, and management are available, there are barriers to accurate diagnosis of pediatric hypertension, including lack of knowledge and complexity of blood pressure standards. We aimed to gain insights into reasons for low rates of diagnosis and treatment from primary care providers. As part of a multisite randomized controlled trial, we interviewed 8 providers in a community health center network. We used a grounded theoretical approach to analyze transcripts. Providers reflected on numerous barriers to diagnosis, management, and follow-up; recommendations for educational content; and how community health center systems can be improved. Findings informed development of a multifaceted intervention. Despite lack of training on essential hypertension, providers were comfortable recommending lifestyle changes to promote healthier weight and reduced blood pressure.

The Use of Ambulatory Blood Pressure Monitoring As Standard of Care in Pediatrics

Hypertension (HTN) is a significant global health problem, responsible for 7.5 million deaths each year worldwide. The prevalence of HTN is increasing in the pediatric population likely attributed to the increase in childhood obesity. Recent work has also shown that blood pressure (BP) tends to track from childhood to adulthood including BP-related target organ damage. In the last 25-30 years, pediatric use of ambulatory blood pressure monitoring (ABPM) has been expanding mainly in the setting of initial elevated BP measurement evaluation, HTN therapy efficacy follow-up, and renal disease. However, there are many clinical areas where ABPM could potentially be used but is currently underutilized. This review summarizes the current knowledge and the uses of pediatric ABPM and explores clinical areas where it can be very useful both to detect HTN and its longitudinal follow-up. And thus, ABPM could serve as a critical tool to potentially prevent early cardiovascular mortality and morbidity in wide variety of populations. With solid data to support ABPM's superiority over clinic BP measurements and these clinical areas for its expansion, ABPM should now be part of standard of care in BP evaluation and management in pediatrics.

Microalbuminuria predicts the recurrence of cardiovascular events in patients with essential hypertension

OBJECTIVES

Microalbuminuria (MAU) is associated with an enhanced risk of cardiovascular events. The prevalence of MAU and its prognostic impact has an important role in the stratification of cardiovascular risk in patients with essential hypertension. This is an observational, prospective study performed by 13 general practitioners aiming at assessing the prevalence and prognostic relevance of MAU in essential hypertension.

METHODS

Patients with essential hypertension and with recent determination of MAU were enrolled into the study by general practitioners, and were followed up for 3 years. Primary end point was the occurrence of major cardiovascular events during the follow-up.

RESULTS

Out of 1024 unselected patients, consecutively enrolled from January 2009 to March 2010, 804 completed the 3-year follow-up. Patients were categorized into two groups according to the absence (n = 523, 65%) or presence (n = 281, 35%) of MAU. During the follow-up, 41 cardiovascular events (1.69 events/100 patient-years) were reported. The presence of MAU was not associated with increased risk of cardiovascular events (adjusted hazard ratio = 1.32; 95% confidence interval 0.290-4.340, P = 0.097). When the analysis was restricted to the patients with previous cardiovascular event, MAU (adjusted hazard ratio = 2.18; 95% confidence interval 0.42-2.43, P = 0.031), together with age, metabolic syndrome, diabetes, and smoking, independently predicted the occurrence of cardiovascular events.

CONCLUSION

Presence of MAU in patients with essential hypertension is not associated with increased risks of cardiovascular events. At the variance, in patients with previous cardiovascular events, MAU was found to predict recurrent events. Thus, the assessment of MAU could be considered a useful tool in secondary prevention.

Low-grade albuminuria and incidence of cardiovascular disease and all-cause mortality in nondiabetic and normotensive individuals

BACKGROUND

Recent studies indicate that, in people with diabetes or hypertension and in the general population, low-grade albuminuria (LGA) below the microalbuminuria threshold is a predictor for incidence of cardiovascular disease (CVD) and mortality. However, it remains unclear whether LGA predicts the risk of CVD incidence and death in nondiabetic and normotensive individuals.

METHODS

A total of 3599 individuals aged not less than 40 years from the general population who are free of CVD in nondiabetic and normotensive individuals with preserved glomerular filtration rate were followed for CVD incidence and all-cause death. LGA was defined as urinary albumin to creatinine ratio (UACR) less than 30  mg/g. It was examined whether there is an association between LGA and CVD incidence or all-cause death.

RESULTS

During the average 5.9 years of follow-up, 61 individuals had first CVD events, and 85 individuals died. The hazard ratios (HRs) for CVD incidence and all-cause death after full adjustment by potential confounders increased significantly in the top tertile of LGA (UACR ≥ 9.6  mg/g for men, ≥ 12.0  mg/g for women) compared with the first tertile [HR = 2.79, 95% confidence interval (CI), 1.41-5.52, HR = 1.69, 95% CI, 1.00-2.84, respectively]. Population-attributable fractions of the top tertile of LGA for CVD incidence and all-cause death were 37.9 and 20.1%, respectively.

CONCLUSION

In apparently healthy individuals with optimal blood pressure and no diabetes, LGA independently predicts CVD incidence and all-cause death, particularly with the large contribution to the excessive incidence 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.

Microalbuminuria, cardiovascular risk factors and cardiovascular morbidity in a British population: The EPIC-Norfolk Population-based Study

BACKGROUND

Microalbuminuria is independently associated with increased cardiovascular risk and renal function deterioration in diabetes and hypertension, but the clinical relevance of raised albuminuria in the general population is less certain. We examined the prevalence of microalbuminuria and its relationship to cardiovascular risk factors and cardiovascular morbidity in the UK general population.

METHODS

Cross-sectional population-based study of 23,964 individuals, aged 40-79 years recruited in 1993-1997 for the EPIC-Norfolk Study. Smoking status, prevalent physician diagnosed diabetes, hypertension, cardiovascular disease and cancer were derived from a health and lifestyle questionnaire. Albumin-to-creatinine ratios were estimated from random spot urine specimens collected at the survey visit, and using these ratios participants were categorized into normoalbuminuria, microalbuminuria (2.5-25 mg/mmol), and macroalbuminuria.

RESULTS

The prevalence of microalbuminuria and macroalbuminuria was 11.8% and 0.9% respectively in the total population and significantly higher in women (14.4%) compared with men (8.9%) (P<0.001). Independent determinants of microalbuminuria were age, sex, systolic blood pressure and current smoking. Microalbuminuria was independently associated with cardiovascular morbidity, after adjusting for known cardiovascular risk factors, with odds ratio (95% confidence interval) for prevalent cardiovascular disease of 1.30 (1.12-1.51) in all men and women.

CONCLUSION

Microalbuminuria was present in approximately 12% of this population. It was independently associated with cardiovascular risk factors and prevalent cardiovascular disease. Microalbuminuria may be a useful indicator of high absolute cardiovascular risk in the community but prospective data are needed to establish its independent predictive value for future events.

Diagnosis, Epidemiology, and Management of Hypertension in Children

National guidelines for the diagnosis and management of hypertension in children have been available for nearly 40 years. Unfortunately, knowledge and recognition of the problem by clinicians remain poor. Prevalence estimates are highly variable because of differing standards, populations, and blood pressure (BP) measurement techniques. Estimates in the United States range from 0.3% to 4.5%. Risk factors for primary hypertension include overweight and obesity, male sex, older age, high sodium intake, and African American or Latino ancestry. Data relating hypertension in childhood to later cardiovascular events is currently lacking. It is known that BP in childhood is highly predictive of BP in adulthood. Compelling data about target organ damage is available, including the association of hypertension with left ventricular hypertrophy, carotid-intima media thickness, and microalbuminuria. Guidelines from both the United States and Europe include detailed recommendations for diagnosis and management. Diagnostic standards are based on clinic readings, ambulatory BP monitoring is useful in confirming diagnosis of hypertension and identifying white-coat hypertension, masked hypertension, and secondary hypertension, as well as monitoring response to therapy. Research priorities include the need for reliable prevalence estimates based on diverse populations and data about the long-term impact of childhood hypertension on cardiovascular morbidity and mortality. Priorities to improve clinical practice include more education among clinicians about diagnosis and management, clinical decision support to aid in diagnosis, and routine use of ambulatory BP monitoring to aid in diagnosis and to monitor response to treatment.

Plasma matrix metalloproteinase-9 and ACE-inhibitor-induced improvement of urinary albumin excretion in non-diabetic, microalbuminuric subjects

Introduction. Elevated plasma matrix metalloproteinase-9 (MMP-9) levels have been suggested to precede the development of microalbuminuria. As angiotensin-converting enzyme (ACE) inhibitors effectively reduce urinary albumin excretion (UAE), in the present study we have investigated the potential association of plasma MMP-9 levels with UAE and treatment effects of ACE-inhibition. Material and methods. In a placebo-controlled

randomised trial we determined plasma MMP-9 levels at baseline and after three months of randomisation to either placebo (n=202) or fosinopril (20 mg/day, n=204) treatment.

Results. Baseline plasma MMP-9 levels were not related to baseline UAE (r=-0.008, p=0.871).Three months of fosinopril treatment effectively reduced UAE compared to placebo treatment (-10.4±2.4 vs. 1.8±1.3 mg/24 hours, p<0.001, respectively). However, fosinopril treatment failed to significantly change plasma MMP-9 levels compared to placebo (-0.47±7.68 vs. 0.06±9.20, p=0.646, respectively) . In addition, the change in UAE was not related with change in MMP-9 levels.

Conclusion. The effective reduction of UAE with fosinopril was not related to plasma MMP-9 levels.

Hidden prevalence of chronic kidney disease in hypertensive patients: the strategic role of primary health care

OBJECTIVE

To identify the hidden prevalence of chronic kidney disease (CKD) in hypertensive patients.

STUDY DESIGN

Cross-sectional study of individuals with systemic arterial hypertension (SAH) who were registered for primary health care (PHC).

METHODS

In total, 293 individuals participated. Data were collected through interviews, as well as biochemical and anthropometric assessments. The CKD-EPI formula was used to identify the occurrence of CKD. Pearson's chi-squared test or Fisher's exact test were used to compare proportions. Prevalence ratios were estimated with a confidence interval of 95% for associations between the explanatory variables and CKD.

RESULTS

Most of the individuals assessed were female (74%), elderly (69%), with a low income (90%), low education levels (84%) and overweight (66.9%). A CKD prevalence of 38.6% (95% CI: 33.0-44.2) was found and approximately 14% were at an advanced stage of the disease. Upon comparison of the variables in the different stages of CKD, statistically significant association could be suggested between CKD and age, education, alcohol intake, overweight individuals, cardiovascular risk, abnormal creatinine and abnormal microalbuminuria. When the prevalence ratio was assessed, association could be suggested between CKD and age, and CKD and creatinine.

CONCLUSION

The high hidden prevalence of CKD confirms the need to train health professionals involved in the treatment of SAH through PHC, enabling the prevention and diagnosis of CKD in its early stages.

[Obesity in metabolic syndrome, as well as kidney dysfunction]

The presence of metabolic syndrome (MS) in a patient allows him to be assigned to a group at high risk for atherosclerosis, cardiovascular events, coronary heart disease, and type 2 diabetes mellitus. In addition, MS negatively affects not only the heart and vessels, but also kidney function, which leads to chronic kidney disease (CKD). MS is pathogenetically associated with CKD and is an independent prognostic factor of the development of the latter, namely, the involvement of the kidney frequently determines prognosis and quality of life in these patients. The paper gives a modern view on the concept of MS and CKD and considers its main diagnostic criteria, etiology, and pathogenesis. The study of the relationships between MS and CKD may suggest that the high prevalence of kidney dysfunction in the general population is largely determined by metabolic nephropathies, including obesity-related nephropathy. The identification of risk factors and poor prognostic markers in this category of patients seems to be extremely important for the early diagnosis of the disease and their timely elimination is one of the main approaches to the comprehensive prevention of CKD in these patients.

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.

The Envy of Scholars: Applying the Lessons of the Framingham Heart Study to the Prevention of Chronic Kidney Disease

During the past 50 years, a dramatic reduction in the mortality rate associated with cardiovascular disease has occurred in the US and other countries. Statistical modeling has revealed that approximately half of this reduction is the result of risk factor mitigation. The successful identification of such risk factors was pioneered and has continued with the Framingham Heart Study, which began in 1949 as a project of the US National Heart Institute (now part of the National Heart, Lung, and Blood Institute). Decreases in total cholesterol, blood pressure, smoking, and physical inactivity account for 24%, 20%, 12%, and 5% reductions in the mortality rate, respectively. Nephrology was designated as a recognized medical professional specialty a few years later. Hemodialysis was first performed in 1943. The US Medicare End-Stage Renal Disease (ESRD) Program was established in 1972. The number of patients in the program increased from 5,000 in the first year to more than 500,000 in recent years. Only recently have efforts for risk factor identification, early diagnosis, and prevention of chronic kidney disease (CKD) been undertaken. By applying the approach of the Framingham Heart Study to address CKD risk factors, we hope to mirror the success of cardiology; we aim to prevent progression to ESRD and to avoid the cardiovascular complications associated with CKD. In this paper, we present conceptual examples of risk factor modification for CKD, in the setting of this historical framework.

Presence of Cardiometabolic Risk Factors Is Not Associated with Microalbuminuria in 14-to-20-Years Old Slovak Adolescents: A Cross-Sectional, Population Study

Introduction

In adults, microalbuminuria indicates generalized endothelial dysfunction, and is an independent risk factor for cardiovascular and all cause mortality. Slovak adults present one of the highest cardiovascular mortality rates in Europe. Thus Slovak adolescents are on a high-risk to develop cardiovascular afflictions early, and screening for microalbuminuria might be useful in early assessment of their cardiovascular risk. We aimed to study the prevalence of microalbuminuria in Slovak adolescents, and the association of urinary albumin-to-creatinine ratio (ACR) to cardiovascular risk factors.

Subjects and methods

Anthropometric data, blood pressure, blood count, glucose homeostasis, lipid profile, renal function, inflammatory status, concentrations of homocysteine and uric acid were determined and associated with ACR in 2 666 adolescents (49.4% boys, 51.6% girls) aged 14-to-20 years. Microalbuminuria was classified as ACR 2.5–25.0 mg/mmol in boys and 3.5–35.0 mg/mmol in girls.

Results

Prevalence of microalbuminuria in both genders reached 3.3%, and did not differ significantly between lean and centrally obese subjects. Girls presented higher ACR than boys (normoalbuminuric: 0.6±0.5 mg/mmol vs. 0.5±0.4 mg/mmol, p>0.001; microalbuminuric: 9.3±7.3 mg/mmol vs. 5.0±3.8 mg/mmol; p>0.001). Microalbuminuric adolescents and those presenting normoalbuminuria within the upper ACR quartile were slimmer than their normoalbuminuric counterparts or adolescents with normoalbuminuria within the lower quartile, respectively. No association between microalbuminuria and cardiovascular risk markers was revealed.

Conclusion

Results obtained in this study do not support our assumption that ACR associates with cardiometabolic risk factors in apparently healthy adolescents. Follow-up studies until adulthood are needed to estimate the potential cardiometabolic risk of apparently healthy microalbuminuric adolescents.

Antihypertensive and vascular remodelling effects of the imperatorin derivative OW1 in renovascular hypertension rats

OW1 is a novel imperatorin derivative that exhibits vasodilator activity. In the present study, the antihypertensive effect of and inhibition of vascular remodelling by OW1 were investigated in two-kidney, one-clip (2K1C) renovascular hypertensive rats. Rats were subjected to the 2K1C procedure and treated with OW1 (40 or 80 mg/kg per day) for 8 weeks. Blood pressure was measured in conscious rats. Microalbumin (mALB) and total protein (U-TP) concentrations were determined in the urine, as were plasma concentrations of angiotensin (Ang) II, calcitonin gene-related peptide (CGRP) and angiotensin-converting enzyme 1 (ACE). The unclipped kidney was stained with haematoxylin and eosin and Masson trichrome, whereas aortic sections were stained with Masson trichrome. In addition, OW1-induced vasodilatation was evaluated in vitro in rat mesenteric and renal arteries. Immunohistochemical analysis was used to quantify collagen I and III expression. OW1 relaxed rat mesenteric and renal arterial rings in vitro. Treatment of 2K1C hypertensive rats with OW1 (40 and 80 mg/kg per day) for 8 weeks significantly decreased blood pressure. In addition, OW1 reduced plasma AngII and ACE concentrations and increased plasma CGRP concentrations. At 80 mg/kg per day, OW1 decreased blood urea nitrogen, mALB and U-TP levels. Histological analysis revealed that OW1 reduced renal arteriolar thickness and relieved the structural hypertrophic arteries. Moreover, OW1 had an inhibitory effect on vascular remodelling and renal lesions in hypertensive rats. In conclusion, the results suggest that OW1 could potentially be a novel candidate for hypertension intervention.

Body mass index (BMI) is associated with microalbuminuria in Chinese hypertensive patients

There is no general consensus on possible factors associated with microalbuminuria in hypertensive patients nor any reported study about this issue in Chinese patients. To examine this issues, 944 hypertensive patients were enrolled in a study based on a cross-sectional survey conducted in Southern China. Multivariate regression analyses were performed to identify the factors related with the presence of microalbuminuria and urinary excretion of albumin. The prevalence of microalbuminuria in hypertensive and non-diabetic hypertensive patients were 17.16% and 15.25%, respectively. Body mass index (BMI), but not waist circumference (WC), were independently associated with microalbuminuria and the values of urinary albumin to creatinine ratio (ACR) based on multiple regression analyses, even after excluding diabetic patients and patients taking inhibitors of the renin-angiotensin system from the analyses. Furthermore, patients with obesity (BMI ≥28) had higher levels of ACR, compared with those with normal weight (BMI <24 kg/m²) and overweight (24 kg/m²≤ BMI < 28). In conclusion, BMI, as a modifiable factor, is closely associated with microalbuminuria among Chinese hypertensive patients, which may provide a basis for future development of intervention approaches for these patients.

Association between low-grade albuminuria and hearing impairment in a non-diabetic Korean population: The Korea National Health and Nutrition Examination Survey (2011-2013)

INTRODUCTION

The objective of the present study was to examine the association between low-grade albuminuria and hearing impairment in the non-diabetic population.

MATERIALS AND METHODS

Data from the Korean National Health and Nutrition Examination Survey 2011-2013 were used in the analyses. Participants were excluded from this study if they were younger than 19 years old, or had urine albumin/creatinine ratio (UACR) ≥ 30 mg/g or diabetes mellitus. There were 10,608 participants included in this study. The participants were divided into three groups according to their UACR tertiles.

RESULTS

There were 1560; 1561; and 1552 male and 1982; 1975; and 1978, female participants in the low, middle, and high tertile groups, respectively. The results indicated the association between low-grade albuminuria and the numbers of metabolic syndrome (MetS) components or Framingham risk score, and the presence of MetS or the proportions of participants at high cardiovascular risk. Univariate and multivariate linear regression analyses demonstrated an association between the UACR and average hearing threshold (AHT) that was observed in both sexes. Multivariate analyses showed that mean AHTs in the low, middle, and high tertile groups were, respectively, 16.127 dB, 17.139 dB, and 18.604 dB for men, and 14.842 dB, 15.100 dB, and 16.353 dB, respectively, for women. Low-frequency, mid-frequency, and high-frequency hearing thresholds according to UACR tertiles showed similar trends. In both sexes, multivariate logistic regression analyses revealed that participants in the low and middle tertile groups had a decreased risk for hearing loss compared to participants in the high tertile group.

CONCLUSION

Low-grade albuminuria was associated with hearing impairment in the non-diabetic participants of this study.

Prognostic Value of Microalbuminuria During Antihypertensive Treatment in Essential Hypertension

Whether changes over time of urinary albumin excretion have prognostic value is a matter of discussion. The objective was to assess the prognostic value of changes in urinary albumin excretion over time in cardiovascular risk during antihypertensive treatment. Follow-up study of 2835 hypertensives in the absence of previous cardiovascular disease (mean age 55 years, 47% men, BP 138/80 mm Hg, 19.1% diabetics, and calibrated systemic coronary risk estimation 5 or >10.6%). Usual-care of antihypertensive treatment was implemented to maintain blood pressure <140/90 mm Hg. Urinary albumin excretion was assessed yearly, and the values were expressed as the creatinine ratio. Incidence of cardiovascular events, fatal and nonfatal, was recorded during the follow-up. During a median follow-up of 4.7 years (17 028 patients-year), 294 fatal and first nonfatal cardiovascular events were recorded (1.73 CVD per 100 patients/year). Independently of blood pressure, estimated glomerular filtration rate, level of cardiovascular risk, and antihypertensive treatment, microalbuminuria at baseline and at any time during the follow-up resulted in higher risk for events, hazard ratio (HR) 1.35 (95% confidence interval [CI], 1.08–1.79) and HR 1.49 (95% CI, 1.14–1.94), respectively. Likewise, development of microalbuminuria (HR 1.60; 95% CI, 1.04–2.46) or persistence from the beginning (1.53; 95% CI, 1.13–2.06) had a significantly higher rate of events than if remained normoalbuminuric (HR 1) or regress to normoalbuminuria (HR 1.37; 95% CI, 0.92–2.06) with an 18%, 18%, 8%, and 11% events, respectively, P <0.001. The study supports the value of urinary albumin excretion assessment as a prognostic factor for cardiovascular risk, but also opens the way to consider it as an intermediate objective in hypertension.

The effects of dipeptidyl peptidase-4 inhibition on microvascular diabetes complications

We performed a review of the literature to determine whether the dipeptidyl peptidase-4 inhibitors (DPP4-I) may have the capability to directly and positively influence diabetic microvascular complications. The literature was scanned to identify experimental and clinical evidence that DPP4-I can ameliorate diabetic microangiopathy. We retrieved articles published between 1 January 1980 and 1 March 2014 in English-language peer-reviewed journals using the following terms: ("diabetes" OR "diabetic") AND ("retinopathy" OR "retinal" OR "nephropathy" OR "renal" OR "albuminuria" OR "microalbuminuria" OR "neuropathy" OR "ulcer" OR "wound" OR "bone marrow"); ("dipeptidyl peptidase-4" OR "dipeptidyl peptidase-IV" OR "DPP-4" OR "DPP-IV"); and ("inhibition" OR "inhibitor"). Experimentally, DPP4-I appears to improve inflammation, endothelial function, blood pressure, lipid metabolism, and bone marrow function. Several experimental studies report direct potential beneficial effects of DPP4-I on all microvascular diabetes-related complications. These drugs have the ability to act either directly or indirectly via improved glucose control, GLP-1 bioavailability, and modifying nonincretin substrates. Although preliminary clinical data support that DPP4-I therapy can protect from microangiopathy, insufficient evidence is available to conclude that this class of drugs directly prevents or decreases microangiopathy in humans independently from improved glucose control. Experimental findings and preliminary clinical data suggest that DPP4-I, in addition to improving metabolic control, have the potential to interfere with the onset and progression of diabetic microangiopathy. Further evidence is needed to confirm these effects in patients with diabetes.

Impact of the albumin to creatinine ratio and the coronary artery state on vascular events

Albuminuria is an important indicator of cardiovascular risk. However, whether albuminuria predicts cardiovascular events independently of the baseline coronary artery state has not yet been investigated. We measured urinary albumin and creatinine concentrations in 867 consecutive patients who underwent coronary angiography for the evaluation of suspected or established stable coronary artery disease (CAD). Albuminuria was defined as a urinary albumin to creatinine ratio of 30 μg/mg or greater. Prospectively, we recorded the vascular events over 3.2 ± 1.2 years. From our patients, 318 had neither albuminuria nor significant CAD (i.e., coronary stenoses ≥ 50%) at baseline angiography, 69 had albuminuria but no significant CAD, 343 did not have albuminuria but significant CAD, and 137 had both albuminuria and significant CAD. Compared with the event rate among patients with neither albuminuria nor significant CAD (8.2%), event rates were significantly higher in patients with albuminuria without significant CAD (18.8%; p = 0.002) and in normoalbuminuric patients with significant CAD (19.2%; p <0.001); it was highest in patients with both albuminuria and significant CAD (33.6%; p <0.001). Importantly, event rates were similar in patients with albuminuria free of significant CAD and those with significant CAD but normoalbuminuria (p = 0.767). In conclusion, this is the first study demonstrating that albuminuria per se is a CAD risk equivalent after adjusting for the angiographically proven atherosclerotic state at baseline.

Contrast-induced nephropathy in aged critically ill patients

Background. Aging is associated with renal structural changes and functional decline. The attributable risk for renal dysfunction from radiocontrast agents in critically ill older patients has not been well established. Methods. In this prospective study, we assessed the incidence of contrast-induced nephropathy (CIN) in critically ill patients with stable renal function who underwent computed tomography with intravenous contrast media. Patients were categorized into two age groups: <65 (YG) or ≥65 years old (OG). CIN was defined as 25% or greater increase from baseline of serum creatinine or as an absolute increase by 0.5 mg/dL until the 5th day after the infusion of contrast agent. We also evaluated the alterations in oxidative stress by assessing serum 8-isoprostane. Results. CIN occurred in 5 of 13 OG patients (38.46%) whereas no YG patient presented CIN (P = 0.015). Serum creatinine kinetics in older patients demonstrated a rise over five days following contrast infusion time while a decline was observed in the YG (P = 0.005). Conclusions. Older critically ill patients are more prone to develop renal dysfunction after the intravenous infusion of contrast agent in relation to their younger counterparts.