Kidney Function and Risk Factors for Left Ventricular Hypertrophy in Untreated Uncomplicated Essential Hypertension

The Prevention of the New Onset of Heart Failure in Hypertensive Patients

In 2014, Japan was estimated to have approximately 27 million patients with hypertension (HT), and the ultimate goal of treatment is to prevent complications of HT, including heart failure (HF). The major structural changes in the heart that cause HF are left ventricular (LV) hypertrophy (LVH) and the resulting LV diastolic dysfunction. However, in patients with HT with well-controlled blood pressure (BP), whether they are in HF stage A (only HT) or B (with organic heart disease) is often unclear. It has been reported that strict BP control suppresses LVH, and the improvement of LVH leads to the suppression of cardiovascular complications. Thus, detecting HF stage B HT and providing appropriate treatment lead to the suppression of HF onset. This review focuses on the detection and treatment of organic heart disease in HT.

Metabolic associated fatty liver disease is a risk factor for chronic kidney disease

BACKGROUND AND AIMS

To clarify the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and chronic kidney disease (CKD).

METHODS

The participants were divided into four groups by the presence or absence of fatty liver disease (FLD) and metabolic dysfunction (MD). MAFLD was defined as having both FLD and MD, whereas CKD was defined as having an estimated glomerular filtration rate of <60 mL/min/1.73 m2 and/or proteinuria.

RESULTS

In this cross-sectional study of 27,371 participants, the proportions of those in the non-FLD without MD, non-FLD with MD, FLD without MD, and MAFLD groups were 48.7, 28.2, 2.3, and 20.8%, respectively. Compared with non-FLD without MD, MAFLD was associated with the risk of CKD (adjusted odds ratio 1.83 [1.66-2.01], P < 0.001), whereas FLD without MD was not (1.02 [0.79-1.33], P = 0.868). Moreover, compared with FLD without MD, MAFLD was associated with the risk of CKD (1.19 [1.09-1.31], P < 0.001). In this retrospective cohort study, 16,938 of 27,371 participants underwent a median 4.6 (2.0-8.1) years follow-up, and incident data of non-FLD without MD, non-FLD with MD, FLD without MD, and MAFLD were 21.0, 31.1, 26.1, and 31.1 cases per 1,000 person-years, respectively. Compared with the non-FLD without MD, MAFLD was associated with the risk of incident CKD (adjusted hazard ratio 1.24 [1.14-1.36], P < 0.001), whereas FLD without MD was not (1.11 [0.85-1.41], P = 0.433).

CONCLUSIONS

MAFLD was associated with a risk of CKD, whereas FLD without MD was not a risk for CKD.

Insulin resistance in chronic kidney disease: a systematic review

Insulin resistance (IR) is an early metabolic alteration in chronic kidney disease (CKD) patients, being apparent when the glomerular filtration rate is still within the normal range and becoming almost universal in those who reach the end stage of kidney failure. The skeletal muscle represents the primary site of IR in CKD, and alterations at sites beyond the insulin receptor are recognized as the main defect underlying IR in this condition. Estimates of IR based on fasting insulin concentration are easier and faster but may not be adequate in patients with CKD because renal insufficiency reduces insulin catabolism. The hyperinsulinemic euglycemic clamp is the gold standard for the assessment of insulin sensitivity because this technique allows a direct measure of skeletal muscle sensitivity to insulin. The etiology of IR in CKD is multifactorial in nature and may be secondary to disturbances that are prominent in renal diseases, including physical inactivity, chronic inflammation, oxidative stress, vitamin D deficiency, metabolic acidosis, anemia, adipokine derangement, and altered gut microbiome. IR contributes to the progression of renal disease by worsening renal hemodynamics by various mechanisms, including activation of the sympathetic nervous system, sodium retention, and downregulation of the natriuretic peptide system. IR has been solidly associated with intermediate mechanisms leading to cardiovascular (CV) disease in CKD including left ventricular hypertrophy, vascular dysfunction, and atherosclerosis. However, it remains unclear whether IR is an independent predictor of mortality and CV complications in CKD. Because IR is a modifiable risk factor and its reduction may lower CV morbidity and mortality, unveiling the molecular mechanisms responsible for the pathogenesis of CKD-related insulin resistance is of importance for the identification of novel therapeutic targets aimed at reducing the high CV risk of this condition.

Inflammation, Endothelial Dysfunction and Increased Left Ventricular Mass in Chronic Kidney Disease (CKD) Patients: A Longitudinal Study

Introduction

Within this longitudinal study we investigated the association of inflammation markers C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) and endothelial dysfunction markers intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) with left ventricular mass indexed for height²·⁷¹ (LVMI) in hypertensive predialysis CKD patients.

Material and Methods

From 2004 to 2005, 182 incident consecutive adult patients from the outpatient CKD clinics of two hospitals in Greece with CKD and hypertension or using antihypertensive medication, were included. Of these, 107 patients underwent CRP (mg/l) and LVMI (g/height²·⁷¹) measurements annually for three years.

Results

In the longitudinal analyses, using linear mixed modeling, a higher IL-6 (ß = 1.9 (95%ci:0.38;3.5), inflammation score based on CRP, IL-6 and TNF-α (ß = 5.0 (95%ci:0.72; 9.4) and VCAM-1 (ß = 0.01 (95%ci:0.005;0.02) were associated with higher LVMI. These models were adjusted for age, gender and primary renal disease, and for confounders that on top changed the beta with ≥10%, i.e. diuretic use (for IL-6 and inflammation score).

Conclusion

The results suggest that in predialysis CKD patients, inflammation as well as endothelial dysfunction may play an important role towards the increase in LVMI.

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.

Individualizing pharmacotherapy in patients with renal impairment: the validity of the Modification of Diet in Renal Disease formula in specific patient populations with a glomerular filtration rate below 60 ml/min. A systematic review

Background

The Modification of Diet in Renal Disease (MDRD) formula is widely used in clinical practice to assess the correct drug dose. This formula is based on serum creatinine levels which might be influenced by chronic diseases itself or the effects of the chronic diseases. We conducted a systematic review to determine the validity of the MDRD formula in specific patient populations with renal impairment: elderly, hospitalized and obese patients, patients with cardiovascular disease, cancer, chronic respiratory diseases, diabetes mellitus, liver cirrhosis and human immunodeficiency virus.

Methods and Findings

We searched for articles in Pubmed published from January 1999 through January 2014. Selection criteria were (1) patients with a glomerular filtration rate (GFR) < 60 ml/min (/1.73m²), (2) MDRD formula compared with a gold standard and (3) statistical analysis focused on bias, precision and/or accuracy. Data extraction was done by the first author and checked by a second author. A bias of 20% or less, a precision of 30% or less and an accuracy expressed as P₃₀% of 80% or higher were indicators of the validity of the MDRD formula. In total we included 27 studies. The number of patients included ranged from 8 to 1831. The gold standard and measurement method used varied across the studies. For none of the specific patient populations the studies provided sufficient evidence of validity of the MDRD formula regarding the three parameters. For patients with diabetes mellitus and liver cirrhosis, hospitalized patients and elderly with moderate to severe renal impairment we concluded that the MDRD formula is not valid. Limitations of the review are the lack of considering the method of measuring serum creatinine levels and the type of gold standard used.

Conclusion

In several specific patient populations with renal impairment the use of the MDRD formula is not valid or has uncertain validity.

Chronic HCV infection increases cardiac left ventricular mass index in normotensive patients

BACKGROUND & AIMS

Left ventricular hypertrophy (LVH), is an independent predictor for cardiovascular events. We investigated if chronic hepatitis C virus (HCV) infection and the related insulin resistance (IR)/hyperinsulinemia could influence the increase of left ventricular mass (LVM).

METHODS

We enrolled 260 outpatients matched for age, body mass index, gender, ethnicity: 52 with never-treated uncomplicated chronic HCV infection (HCV(+)), 104 never-treated hypertensives (HT) and 104 healthy subjects (NT). LVM was calculated according to the Devereux formula and indexed for body surface area. The following laboratory parameters were measured: fasting plasma glucose and insulin, total, LDL- and HDL-cholesterol, triglyceride, creatinine, e-GFR-EPI, HOMA. Quantitative HCV-RNA was assessed by PCR.

RESULTS

HCV(+) patients with respect to healthy normotensive subjects had an increased LVMI (100 ± 23 vs. 83 ± 15 g/m(2); p < 0.0001), similar to that observed in HT group (103 ± 25 g/m(2)). Regarding biochemical variables, HCV(+) patients, in comparison with normotensive healthy subjects, had higher triglyceride, creatinine, fasting insulin and HOMA (3.2 ± 1.3 vs. 2.5 ± 1.0; p < 0.0001). At linear regression analysis, the correlation between LVMI and HOMA was similar in HT (r = 0.528, p < 0.0001) and HCV(+) (r = 0.489, p < 0.0001) groups. At multiple regression analysis, HOMA resulted the major determinant of LMVI in all groups, explaining respectively 21.8%, 27.8%, and 23.9% of its variation in NT, HT and HCV(+). At correlational analysis HCV-RNA and HOMA demonstrated a strong and linear relationship between them, explaining the 72.4% of their variation (p = 0.022).

CONCLUSIONS

We demonstrated a significant and direct correlation between HOMA and LVMI in patients with chronic HCV infection, similar to that observed in hypertensives.

Renal disease and left atrial remodeling predict atrial fibrillation in patients with cardiovascular risk factors

OBJECTIVES

In this prospective population-based study, we tested the possible interaction between chronic kidney disease (CKD) and left atrium volume index (LAVI) in predicting incident atrial fibrillation (AF).

METHODS

We enrolled 3549 Caucasian subjects, 1829 men and 1720 women, aged 60.7 ± 10.6 years, without baseline AF and thyroid disorders. Echocardiographic left ventricular mass and LAVI were measured. Renal function was calculated by estimated glomerular filtration rate (e-GFR). To test the effect of some clinical confounders on incident AF, we constructed different models including clinical and laboratory parameters. AF diagnosis was made by standard electrocardiogram or 24-h ECG-Holter, hospital discharge diagnoses, and by the all-clinical documentation.

RESULTS

During the follow-up (53.3 ± 18.1 months), 546 subjects developed AF (4.5 events/100 patient-years). Progressors to AF were older, had a higher body mass index, blood pressure, LDL-cholesterol, glucose, cardiac mass, and LAVI, and had lower e-GFR. Hypertension, metabolic syndrome, diabetes, cardiac hypertrophy and CKD were more common among AF cases than controls. In the final Cox regression model, variables that remained significantly associated with AF were: cardiac hypertrophy (HR=1.495, 95% CI=1.215-1.841), renal disease (HR=1.528, 95% CI=1.261-1.851), age (HR=1.586, 95% CI=1.461-1.725) and LAVI (HR=2.920, 95% CI=2.426-3.515). The interaction analysis demonstrated a synergic effect between CKD and cardiac hypertrophy (HR=4.040, 95% CI=2.661-6.133), as well as between CKD and LAVI (HR=4.875, 95% CI=2.699-8.805). The coexistence of all three subclinical organ damages significantly increases the arrhythmic risk (HR=7.185, 95% CI=5.041-10.240).

CONCLUSIONS

Our data demonstrate that LAVI and CKD significantly interact in a synergic manner in increasing AF risk.

Subclinical nephrosclerosis is linked to left ventricular hypertrophy independent of classical atherogenic factors

Recently, cardio-renal interactions have been considered to be important and it has been demonstrated that mild renal dysfunction is associated with left ventricular hypertrophy (LVH). However, the correlation between LVH and subclinical renal damage is unclear. We investigated this association by assessing pretransplant biopsies from living kidney donors with normal renal function. We retrospectively categorized 238 living kidney donors into tertiles according to the percentage of global glomerulosclerosis (%GGS) observed in pretransplant biopsies (low, 0-3.45% (n=80); moderate, 3.46-11.76% (n=78); high, ⩾11.77% (n=80)) to analyze trends in their left ventricular mass index (LVMI) measured by echocardiography and baseline factors. LVH was defined as LVMI >110 g m(-2) in female and >125 g m(-2) in male subjects. We used a logistic regression model to evaluate any correlations between %GGS and LVH. LVMI increased significantly with increasing tertiles of %GGS, as did the prevalence of left ventricular remodeling and LVH. According to multivariate logistic regression analysis, subjects with high %GGS tertiles had a sevenfold greater risk of LVH than did those with low tertiles, even after adjusting for age, sex, systolic blood pressure, history of diabetes mellitus, total serum cholesterol and glomerular filtration rate (GFR) measured by a radioisotopic technique. There is an association between GGS and LVH in subjects with normal renal function. This association is significant after adjustment for age, sex, blood pressure, GFR and other atherogenic factors.

Effect of early stage kidney disease on cardiac mass: comparison to post-donation renal function

BACKGROUND/AIM

In chronic renal failure the increase in cardiovascular risk is in part related to the high prevalence of left ventricular hypertrophy. The aim of the present monocentric retrospective study was to evaluate the influence of the presence of parenchymal kidney disease on left ventricular geometry in normotensive (arterial pressure <140/90 mm Hg) patients (KD+, n = 50, mean age 39 ± 19 years) with mild to moderate renal failure (stage 2-3 chronic kidney disease).

METHODS

Left ventricular geometry was estimated by echocardiography and compared to a group of healthy subjects with similarly reduced renal function as a consequence of renal donation (KD-, n = 63, mean age 52 ± 12 years).

RESULTS

Subjects with and without kidney disease had similar blood pressure, body mass index and isotopic glomerular filtration rate. Left ventricular mass (LVM) indexed to body surface area was greater in KD+ as compared to KD- subjects and the difference was more pronounced in women than in men. The increase in LVM in KD+ patients was associated with lower albuminemia and hematocrit, and a higher plasma renin activity and aldosterone as compared to KD- subjects. In multivariate analysis, kidney disease emerged as an important determinant of LVM index independently of age, gender and blood pressure.

CONCLUSION

This observation suggests that the presence of kidney disease has an independent amplifying effect on LVM which could be related to volume overload and/or prohypertrophic factors such as aldosterone.

Absence of an independent association between serum uric acid and left ventricular mass in Caucasian hypertensive women and men

BACKGROUND AND AIM

Experimentally uric acid may induce cardiomyocyte growth and interstitial fibrosis of the heart. However, clinical studies exploring the relationship between serum uric acid (SUA) and left ventricular (LV) mass yielded conflicting results. The aim of our study was to evaluate the relationships between SUA and LV mass in a large group of Caucasian essential hypertensive subjects.

METHODS AND RESULTS

We enrolled 534 hypertensive patients free of cardiovascular complications and without severe renal insufficiency. In all subjects routine blood chemistry, including SUA determination, echocardiographic examination and 24 h ambulatory blood pressure (BP) monitoring were obtained. In the overall population we observed no significant correlation of SUA with LV mass indexed for height(2.7) (LVMH(2.7)) (r = 0.074). When the same relationship was analysed separately in men and women, we found a statistically significant correlation in female gender (r = 0.27; p < 0.001), but not in males (r = -0.042; p = NS). When we grouped the study population in sex-specific tertiles of SUA, an increase in LVMH(2.7) was observed in the highest tertiles in women (44.5 ± 15.6 vs 47.5 ± 16 vs 55.9 ± 22.2 g/m(2.7); p < 0.001), but not in men. The association between SUA and LVMH(2.7) in women lost statistical significance in multiple regression analyses, after adjustment for age, 24 h systolic BP, body mass index, serum creatinine and other potential confounders.

CONCLUSIONS

Our findings do not support an independent association between SUA and LV mass in Caucasian men and women with arterial hypertension.

Circulating soluble receptor for advanced glycation end product (sRAGE) and left ventricular hypertrophy in patients with chronic kidney disease (CKD)

BACKGROUND AND AIM

A decoy receptor for advanced glycation end product (soluble RAGE or sRAGE) is involved in left ventricular hypertrophy (LVH), and cardiomyopathy myocardial damage in experimental models and observational studies in patients with heart failure support the hypothesis that sRAGE attenuates the progression of heart disease and prevents death. Since sRAGE accumulates in patients with chronic kidney disease (CKD) we studied the relationship between plasma sRAGE with LVH in CKD patients.

METHODS AND RESULTS

We enrolled 142 patients with an average estimated glomerular filtration rate (eGFR) of 32 ml/min/1.73 m(2) and 49 healthy control individuals matched for age and gender. Plasma sRAGE was significantly higher in CKD patients than in healthy controls. Significant inverse relationships were found between sRAGE with left ventricular mass index (LVMI) and mean wall thickness (MWT) but no such associations were found in controls. A bootstrap re-sampling validation study confirmed the estimates of the link between sRAGE and these variables. On covariance analysis, the slopes of LVMI and MWT to sRAGE were significantly steeper in CKD patients than in the controls. On logistic regression analysis 1 log unit increase in sRAGE was associated with a 82% decrease in the odds for LVH in CKD patients.

CONCLUSIONS

sRAGE is an inverse marker of LVH in CKD patients. This association generates the hypothesis that the RAGE pathway could be a causal risk factor for LVH in this population and that blockade of this pathway by the endogenous decoy receptor sRAGE could attenuate LVH in the same population.

Thyroid hormone within the normal range is associated with left ventricular mass in patients with hypertension

Thyroid hormone amplifies hypertrophy of cardiac myocytes. The heart is influenced by the minimal changes of thyroid hormone levels. We hypothesized that thyroid hormone within the normal reference range may be associated with left ventricular (LV) mass in hypertensive subjects. We performed echocardiography to assess LV mass indexed by body surface area (LVMI), and measured thyroid stimulating hormone (TSH), free triiodo-thyronine (fT3), free thyroxine (fT4), and brain natriuretic peptide (BNP) in 318 hypertensive patients without known thyroidal diseases. Glomerular filtration rate (GFR) was estimated using the MDRD formula. Relationship between each thyroid hormone and LVMI in hypertensive patients with euthyroidism were investigated using a multiple linear regression model entering age, gender, height, weight, GFR, log BNP, systolic BP, the use of more than 2 different types of antihypertensive medications, and HbA1c as covariates. Thyroid hormone and TSH levels were within the normal range in 293 patients. In these patients, fT3 (standard β = 0.13) and fT4 (standard β = 0.11) positively, and TSH (standard β = -0.15) inversely correlated with LVMI in the multiple linear regression model. Thyroid hormone may be associated with LV remodeling independent of renal and LV dysfunctions in hypertensive patients with euthyroidism.

Lifestyle interventions, insulin resistance, and renal artery stiffness in essential hypertension

The study investigates lifestyle and effective anti-hypertensive intervention in overweight-obese patients can influence insulin-resistance (HOMA-IR) and US Renal-Resistive-Index (RRI). After a 1-year interventional program (including a personalized Mediterranean diet, physical activity increase, smoking withdrawal counseling), 156 Essential Hypertension (EH) patients still have abnormal HOMA-IR, significantly higher in comparison to 159 control group patients. Body mass index (BMI) and cholesterol-high-density-lipoprotein improvement are the best predictors of a HOMA-IR decrease; RRI improves in EH according to lifestyle interventions, but no predictor to RRI is identified. Persistence of IR can be tentatively assumed as a steady sign, persistent also after extended lifestyle intervention in EH, further warranting more intensive dietary interventions.

Renal and cardiac abnormalities in primary hypertension

OBJECTIVE

The relationship between mild reduction in renal function and cardiac structure and function have not yet been fully elucidated. We investigated cardiac and renal abnormalities in 400 untreated, nondiabetic patients (65% men, mean age 47 years) with primary hypertension and normal serum creatinine.

METHODS

Renal abnormalities were defined as creatinine clearance less than 75 ml/min per 1.73 m2 (Cockcroft-Gault formula) and/or the presence of microalbuminuria (albumin-to-creatinine ratio). Left ventricular structure and function were assessed by echocardiography.

RESULTS

The prevalence of microalbuminuria and reduced creatinine clearance was 13 and 31%, respectively. Patients with renal abnormalities shared greater left ventricular mass index, higher prevalence of left ventricular hypertrophy, and unfavorable geometric patterns. Microalbuminuria was also associated with inappropriate left ventricular mass and depressed midwall fractional shortening, whereas reduced creatinine clearance was associated with lower stroke volume and higher central pulse pressure/stroke volume ratio and total peripheral resistance. Stepwise regression analysis showed that both albuminuria and creatinine clearance were independently related to left ventricular mass. Logistic regression analysis of the reciprocal interaction of microalbuminuria and reduced creatinine clearance on the occurrence of subclinical cardiac damage showed that reduced creatinine clearance entailed a greater risk of left ventricular hypertrophy in patients with normal albuminuria alone, whereas the presence of microalbuminuria was associated with a greater risk of left ventricular hypertrophy independently of creatinine clearance.

CONCLUSIONS

These findings provide further proof of the role of cardiorenal interaction in the development of hypertension-related cardiovascular disease, and may have clinical implications.