Blood pressure independent association of microalbuminuria and left ventricular hypertrophy in hypertensive men

The association between EKG abnormalities and the development of microalbuminuria in type 2 diabetes

Microalbuminuria is associated with both with chronic kidney disease and various cardiovascular abnormalities. Given the common use of electrocardiograms (EKGs) in diagnosing cardiovascular dysfunction, this study is analyzing the relationship between EKG abnormalities and diabetic nephropathy in type 2 diabetes mellitus (DM) patients. The enrollments of this study were from the 10-year follow-up data (2003-2012) of the Diabetes Management through an Integrated Delivery System project. All study subjects underwent at least 1 EKG measurement. The urinary microalbuminuria was recorded annually. The logistic regression model was used to evaluate the association between EKG abnormalities and the occurrence of diabetic nephropathy in type 2 DM patients. The total of 1189 patients with type 2 DM are included in this study and a total of 552 patients had microalbuminuria during a 10-year follow-up. A significantly higher odds ratio of microalbuminuria occurrence (4.85) was found in the patients with premature supraventricular contraction or tachycardia compared to those without EKG abnormalities. The odds ratios of microalbuminuria occurrence were 1.00, 2.43, 2.64, and 2.98, respectively, for patients with insulin resistance in the Q (quartile) 1(as the reference), Q2, Q3, and Q4, respectively. Our findings can serve as a reference for the association between EKG abnormalities and the development of microalbuminuria in type 2 diabetes.

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Microalbuminuria in subjects with hypertension attending specialist blood pressure clinics

Albuminuria is associated with increased risk of cardiovascular disease and target organ damage in patients with diabetes mellitus. In nondiabetic hypertensive patients, the threshold at which microalbuminuria (MAU) increases risk is unclear and there is evidence that cardiovascular risk may be increased in individuals with MAU levels lower than the usual recommended screening thresholds. We compared two definitions of MAU (on the basis of three early morning urine samples) in a cohort of hypertensive patients attending two specialist clinics in Scotland: conventional (MAU(C)) albumin-to-creatinine ratio (ACR) >2.5-25 mg mmol(-1) in males or >3.5-25 mg mmol(-1) in females; and low-grade (MAU(L)) ACR 1.2-2.5 in males or 1.7-3.5 mg mmol(-1) in females. Of the 1059 subjects screened, 786 (74%) were nondiabetic, with estimated glomerular filtration rate ⩾30 ml min(-1) per 1.73 m(2) and without gross proteinuria (low-risk subset). The average age was 58±15 years, body mass index 30±6 kg m(-2) and 46% were males. The prevalence of MAU(C) was 11% and 9.5% in the overall and low-risk subset, respectively, whereas MAU(L) prevalence was 11.1% and 10% respectively. The prevalence of cardiovascular disease was higher (24%) with albuminuria (both MAU(C) and MAU(L)) compared with 14% among those without albuminuria. The use of MAU(L) doubled the number of hypertensive subjects with increased cardiovascular risk who can be targeted for more rigorous risk reduction strategies. Consideration should be given to reducing the current threshold for MAU.

Increased Klk9 Urinary Excretion Is Associated to Hypertension-Induced Cardiovascular Damage and Renal Alterations

Early detection of hypertensive end-organ damage and secondary diseases are key determinants of cardiovascular prognosis in patients suffering from arterial hypertension. Presently, there are no biomarkers for the detection of hypertensive target organ damage, most outstandingly including blood vessels, the heart, and the kidneys.We aimed to validate the usefulness of the urinary excretion of the serine protease kallikrein-related peptidase 9 (KLK9) as a biomarker of hypertension-induced target organ damage.Urinary, plasma, and renal tissue levels of KLK9 were measured by the Western blot in different rat models of hypertension, including angiotensin-II infusion, DOCA-salt, L-NAME administration, and spontaneous hypertension. Urinary levels were associated to cardiovascular and renal injury, assessed by histopathology. The origin of urinary KLK9 was investigated through in situ renal perfusion experiments.The urinary excretion of KLK9 is increased in different experimental models of hypertension in rats. The ACE inhibitor trandolapril significantly reduced arterial pressure and the urinary level of KLK9. Hypertension did not increase kidney, heart, liver, lung, or plasma KLK9 levels. Hypertension-induced increased urinary excretion of KLK9 results from specific alterations in its tubular reabsorption, even in the absence of overt nephropathy. KLK9 urinary excretion strongly correlates with cardiac hypertrophy and aortic wall thickening.KLK9 appears in the urine in the presence of hypertension as a result of subtle renal handling alterations. Urinary KLK9 might be potentially used as an indicator of hypertensive cardiac and vascular damage.

Cardiac structural and functional changes in old elderly patients with obstructive sleep apnoea-hypopnoea syndrome

OBJECTIVE

To investigate cardiac structural changes in elderly patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) and the impact on left ventricular systolic and diastolic function.

METHODS

The study enrolled elderly patients with OSAHS and age-matched healthy control subjects. Cardiac structure, left ventricular diastolic function and left ventricular systolic function were measured using a Doppler ultrasound scanner and compared between the two groups.

RESULTS

The study included 136 patients with OSAHS and 50 healthy control subjects. There were significant differences in the echocardiography indicators that reflect cardiac structure, including interventricular septum, left ventricle posterior wall thickness, and left ventricular mass and mass index between the two groups. There were significant differences between the two groups in the ventricular septal early diastolic myocardial peak velocity/late diastolic myocardial peak velocity (Em/Am), mitral annulus Em/Am, and left ventricle posterior wall Em/Am. There were also significant differences in the indicators of interventricular septum, mitral annulus and left ventricular posterior wall systolic peak velocity between the two groups.

CONCLUSION

Elderly patients with OSAHS demonstrated cardiac structural changes and their left ventricular diastolic and systolic functions were significantly diminished.

Proteinuria and its relation to cardiovascular disease

Chronic kidney disease (CKD) and its associated morbidity pose a worldwide health problem. As well as risk of endstage renal disease requiring renal replacement therapy, cardiovascular disease is the leading cause of premature death among the CKD population. Proteinuria is a marker of renal injury that can often be detected earlier than any tangible decline in glomerular filtration rate. As well as being a risk marker for decline in renal function, proteinuria is now widely accepted as an independent risk factor for cardiovascular morbidity and mortality. This review will address the prognostic implications of proteinuria in the general population as well as other specific disease states including diabetes, hypertension and heart failure. A variety of pathophysiological mechanisms that may underlie the relationship between renal and cardiovascular disease have been proposed, including insulin resistance, inflammation, and endothelial dysfunction. As proteinuria has evolved into a therapeutic target for cardiovascular risk reduction in the clinical setting we will also review therapeutic strategies that should be considered for patients with persistent proteinuria.

Urinary protein excretion is associated with left ventricular hypertrophy in treatment-naïve hypertensive patients in an african hospital setting

BACKGROUND

Left ventricular hypertrophy (LVH) is an independent predictor of fatal and non-fatal cardiovascular events in hypertensive patients. Current guidelines for the management of hypertension are based on cardiovascular risk stratification. This study evaluated the possibility that an inexpensive, simple random, single-void urinary protein-to-creatinine ratio (UPCR) would be associated to left ventricular (LV) mass in a black African setting, and therefore direct appropriate management of these patients.

METHODS

We measured echocardiographic LV mass and a random spot UPCR in 34 untreated newly diagnosed hypertensive patients attending the cardiology consultation unit at the Yaoundé General Hospital. LV mass was indexed to height (in m(2.7)) to obtain the LV mass index (LVMI). A regression model was used to verify the independent association between UPCR and LVMI.

RESULTS

The mean age of our patients was 52.65 years, and the mean systolic and diastolic blood pressures were 152.44 and 92.84 mm Hg, respectively. The prevalence of LVH was 41.2%. UPCR was higher in patients with LVH compared to those without (p = 0.043). There was a significant correlation between UPCR and LVMI (r = 0.581, p < 0.001). In the multiple linear regression model, UPCR was associated with LVMI independent of systolic blood pressure (p < 0.001).

CONCLUSION

Random spot UPCR is associated with an increased LV mass and may be very useful in screening and guiding appropriate management of high-risk untreated hypertensive patients.

Parallel deterioration of albuminuria, arterial stiffness and left ventricular mass in essential hypertension: integrating target organ damage

BACKGROUND

Albuminuria, arterial stiffening and left ventricular hypertrophy (LVH) constitute target organ damage. We estimated whether increased urinary albumin excretion, assessed by albumin-to-creatine ratio (ACR), and carotid to femoral pulse wave velocity (c-f PWV) were accompanied by augmented left ventricular (LV) mass index (LVMI) in hypertension.

METHODS

In 428 non-diabetic untreated hypertensives (257 men, mean age = 52 years, office blood pressure (BP) = 146/93 mm Hg) the distributions of ACR and c-f PWV were split by the median (8 mg/g and 7.8 m/s, respectively).

RESULTS

Age, male sex, 24 h systolic BP, ACR and c-f PWV were the independent predictors of LVMI (R(2) = 0.478, p < 0.0001). Among patients with low ACR (n = 198), those with high c-f PWV (n = 84) compared to those with low c-f PWV (n = 114) were characterized by increased LVMI (by 8.9 g/m(2), p = 0.012) and prevalence of LVH (30 vs. 14%, p = 0.015). Similarly among patients with high ACR (n = 230), those with high c-f PWV (n = 123) compared to those with low c-f PWV (n = 107) exhibited heightened LVMI (by 13.6 g/m(2), p = 0.001).

CONCLUSIONS

Increased ACR in conjunction with pronounced arterial stiffness is accompanied by augmented LV mass and higher LVH rates. Furthermore, the interrelationships between albuminuria, c-f PWV and LVMI suggest parallel target organ damage progression.

The progressive pathway of microalbuminuria: from early marker of renal damage to strong cardiovascular risk predictor

There is clear evidence that urinary albumin excretion levels, even below the cut-off values currently used to diagnose microalbuminuria, are associated with an increased risk of cardiovascular events. The relationships of microalbuminuria with a variety of risk factors, such as hypertension, diabetes and metabolic syndrome and with several indices of subclinical organ damage, may contribute, at least in part, to explain the enhanced cardiovascular risk conferred by microalbuminuria. Nonetheless, several studies showed that the association between microalbuminuria and cardiovascular disease remains when all these risk factors are taken into account in multivariate analyses. Therefore, the exact pathophysiological mechanisms explaining the association between microalbuminuria and cardiovascular risk remain incompletely understood. The simple search for microalbuminuria in hypertensive patients may enable the clinician to better assess absolute cardiovascular 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 cardiovascular risk factors.

Proteinuria and clinical outcomes in hypertensive patients

This narrative review focuses on outcomes related to proteinuria in hypertension (HT), and also examines the role of current and future therapeutic strategies. Proteinuria is an independent marker of renal and cardiovascular (CV) disease in hypertensive populations, particularly in high-risk groups such as diabetic patients. Effective blood pressure (BP) control and proteinuria management are associated with significant improvements in the risk of key adverse outcomes, although a causative relationship needs careful assessment. Available antihypertensives have varying effects on proteinuria reduction. Drugs affecting the renin system offer antiproteinuric and renoprotective effects that are probably at least partially independent of their BP effects. Economic evaluations of these interventions confirm their cost-saving benefits relative to other antihypertensives, but outcomes-based research is needed in some settings.

Left ventricular hypertrophy and clinical outcomes in hypertensive patients

The prevalence of left ventricular hypertrophy (LVH) rises with severity of hypertension (HT), age, and obesity. Its prevalence ranges from 20% in mildly hypertensive patients to almost 100% in those with severe or complicated HT. However, the diagnosis of LVH is not straightforward, and the definitions and criteria used in clinical studies lack consistency. While many factors play a role in the onset and progression of LVH, blood pressure (BP) is recognized as a central factor. Twenty-four-hour BP measurements are more closely related to LVH than conventional BP readings taken in the clinician's office. Increased renin-angiotensin system (RAS) activity also plays an important role in the development of LVH, and various studies show a correlation between plasma renin activity and left ventricular mass (LVM). LVH is a recognized marker of HT-related target organ damage, and a strong and independent risk factor for adverse cardiovascular (CV) outcomes. CV risk increases with increasing LVM, and decreases with regression of LVH in response to antihypertensive treatment. Therefore the detection, prevention, and reversal of LVH are important goals in HT management. Most antihypertensive drugs can attenuate BP and LVH. However, each drug class may induce LVH regression to a different extent and these extents seldom correlate with the degree of BP reduction achieved. Data from the few large comparative studies in this area suggest that certain classes of antihypertensive drugs and/or their combinations are more effective than others. In particular, calcium channel blockers and drugs that target the RAS, such as angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), appear to have a specific effect on LVH, independent of BP reduction. Guidelines, therefore, have recommended these drug classes for the treatment of hypertensive patients with LVH.

Prevention of heart failure: a scientific statement from the American Heart Association Councils on Epidemiology and Prevention, Clinical Cardiology, Cardiovascular Nursing, and High Blood Pressure Research; Quality of Care and Outcomes Research Interdisciplinary Working Group; and Functional Genomics and Translational Biology Interdisciplinary Working Group

The increase in heart failure (HF) rates throughout the developed and developing regions of the world poses enormous challenges for caregivers, researchers, and policymakers. Therefore, prevention of this global scourge deserves high priority. Identifying and preventing the well-recognized illnesses that lead to HF, including hypertension and coronary heart disease, should be paramount among the approaches to prevent HF. Aggressive implementation of evidence-based management of risk factors for coronary heart disease should be at the core of HF prevention strategies. Questions currently in need of attention include how to identify and treat patients with asymptomatic left ventricular systolic dysfunction (Stage B HF) and how to prevent its development. The relationship of chronic kidney disease to HF and control of chronic kidney disease in prevention of HF need further investigation. Currently, we have limited understanding of the pathophysiological basis of HF in patients with preserved left ventricular systolic function and management techniques to prevent it. New developments in the field of biomarker identification have opened possibilities for the early detection of individuals at risk for developing HF (Stage A HF). Patient groups meriting special interest include the elderly, women, and ethnic/racial minorities. Future research ought to focus on obtaining a much better knowledge of genetics and HF, especially both genetic risk factors for development of HF and genetic markers as tools to guide prevention. Lastly, a national awareness campaign should be created and implemented to increase public awareness of HF and the importance of its prevention. Heightened public awareness will provide a platform for advocacy to create national research programs and healthcare policies dedicated to the prevention of HF.

Relation of albuminuria to left ventricular mass (from the HyperGEN Study)

Although albuminuria has been associated with a larger left ventricular (LV) mass in hypertensive and diabetic populations, little is known about this association in normotensive adults. We hypothesized that albuminuria is positively associated with LV mass in normotensive and hypertensive subjects. We analyzed data from 3,445 participants of the Hypertension Genetic Epidemiology Network (HyperGEN) Study (mean age 48.6 +/- 13.7 years, range 18 to 87, 57% women). LV parameters were obtained by echocardiography. Urinary albumin was estimated using standard methods. From the lowest to highest quartile of albuminuria, multivariable adjusted means of LV mass indexed to body surface area were 71.9, 73.3, 74.0, and 76.5 g/m2, respectively (p for trend = 0.002) in normotensive participants. Corresponding values for hypertensive subjects were 87.4, 89.3, 92.3, and 94.9 g/m2, respectively (p for trend <0.0001). Similar results were observed for LV mass indexed to height2.7. In secondary analyses, we found similar associations for men and women and after exclusion of subjects with diabetes. Furthermore, positive associations were observed between albuminuria and LV wall thickness in hypertensive and normotensive subjects. Albuminuria was negatively related to ejection fraction only in hypertensive subjects. In conclusion, these results suggest that albuminuria is positively associated with LV mass in normotensive subjects as it is in hypertensive subjects.

Relation of left ventricular hypertrophy with systemic inflammation and endothelial damage in resistant hypertension

The relation between left ventricular hypertrophy (LVH) and unfavorable cardiovascular prognosis may involve systemic inflammation and endothelial dysfunction/damage. The aim of this study was to investigate in a cross-sectional design the relationships of LVH with C-reactive protein (CRP) levels (a marker of systemic low-grade inflammation) and with microalbuminuria (a marker of glomerular endothelial damage) in 705 patients with resistant hypertension. At baseline, all were submitted to a laboratory evaluation including 24-hour urinary albumin excretion, 2D echocardiogram, and 24-hour ambulatory blood pressure monitoring. A total of 463 patients also had high-sensitivity CRP levels determined. LVH was defined as an indexed left ventricular mass >110 g/m(2) in women and >125 g/m(2) in men. Microalbuminuria was evaluated in 3 categories: low normal (<15 mg/24 hours), high normal (between 15 and 29 mg/24 hours), and abnormal (between 30 and 299 mg/24 hours). CRP was dichotomized at the median value (3.7 mg/L). Associations with LVH were examined after adjustment for all of the potential confounders by multivariate logistic regression. A total of 534 patients (75.7%) had LVH. After full adjustment, both abnormal microalbuminuria (odds ratio: 1.97; 95% CI: 1.04 to 3.73) and high CRP (OR: 1.76; 95% CI: 1.06 to 2.93) were independently associated with LVH occurrence. The high-normal albuminuria was associated with a borderline significant 46% increased chance of having LVH. Furthermore, the association between high CRP and LVH was observed exclusively in the subgroup with normal albuminuria. In conclusion, both systemic inflammation and endothelial damage were associated with LVH occurrence. These relationships offer insight into the pathophysiological mechanisms linking LVH to atherosclerosis and to increased cardiovascular morbidity and mortality.

Incidence of new stroke or new myocardial infarction or death at 39-month follow-up in patients with diabetes mellitus, hypertension or both with and without microalbuminuria

We investigated in 306 patients, mean age 57 +/- 10 years, with diabetes mellitus (202 patients) or hypertension (179 patients) whether microalbuminuria was a significant independent risk factor for the development of new stroke or new myocardial infarction (MI) or death. At 39-month follow-up, new stroke or new MI or death developed in 44 of 111 patients (40%) with microalbuminuria and in 38 of 195 patients (19%) without microalbuminuria (p = 0.0001). Stepwise Cox regression analysis showed that significant independent predictors of the time to development of new stroke or new MI or death were (1) diabetes (risk ratio = 1.76), (2) left ventricular (LV) mass index (risk ratio = 1.020 for each 1 g/m(2) increase), (3) prior stroke (risk ratio = 5.39), and (4) prior MI (risk ratio = 3.29). Microalbuminuria was not a significant independent predictor of new stroke or new MI or death, but LV mass index, diabetes mellitus, prior stroke, and prior MI were significant independent predictors.

α-Adducin and angiotensin-converting enzyme polymorphisms in hypertension: evidence for a joint influence on albuminuria

BACKGROUND

A single-nucleotide polymorphism (Gly460Trp) within the alpha-adducin gene (ADD1) may influence several renal phenotypes, including salt sensitivity, susceptibility to renal failure, the renal haemodynamics and confer a worse cardiovascular risks profile. However, its relationship with microalbuminuria, a marker of early renal and cardiovascular damage and an independent predictor of morbid events in hypertension, is unknown. For this reason, we related the ADD1 genetic polymorphism to urine albumin levels and other clinical variables in essential hypertensive men. The angiotensin-converting enzyme (ACE) insertion/deletion (ID) polymorphism was also evaluated because of its interactive potential with the ADD1 genotype.

METHODS

Albuminuria (three overnight collections), echocardiographic left ventricular mass index, blood pressure, body mass index, renal function, glucose and lipids were measured in 238 genetically unrelated, never treated, uncomplicated Caucasian essential hypertensive men. Polymerase chain reaction or a 5' nuclease assay were used to characterize the ACE ID and ADD1 Gly460Trp variants, respectively.

RESULTS

Microalbuminuria (albuminuria >or= 15 microg/min) was more frequent in patients with the ACE DD variant, but only in those with a ADD1 Gly460Gly background. In contrast, urine albumin did not differ by ACE ID genotype in the presence of mutated ADD1 Trp alleles. ADD1 polymorphisms per se were not associated with albuminuria. Cardiovascular, renal, metabolic parameters were homogeneously distributed among different genetic backgrounds.

CONCLUSIONS

ACE DD and ADD1 Gly460Gly polymorphisms may jointly influence albuminuria in hypertensive men, 460Gly homozygosis facilitating or, possibly, the 460Trp allele mitigating the noxious renal impact of the ACE DD genotype. The data highlight further the complex pathophysiological implications of microalbuminuria in hypertension.

QT dispersion: comparison between participants with Type 1 and 2 diabetes and association with microalbuminuria in diabetes

BACKGROUND AND AIMS

The interlead variation of QT duration in surface electrocardiogram [ECG; QT dispersion (QTd)] has been shown to predict mortality in both diabetic and general population. Diabetic cardiac autonomic neuropathy (CAN) is a common complication of diabetes, and it is also associated with worse prognosis among the diabetic population. In this study, we investigated the association between QTd duration and CAN, as well as other complications of diabetes in participants with Types 1 and 2 diabetes.

METHODS

A total of 184 patients with either Type 1 (n=63) or 2 (n=121) diabetes, as well as 100 control participants, matched for age and sex with the diabetic individuals, were studied. QT and RR intervals were measured on 12 leads of resting ECG tracing. QTd was calculated semiautomatically using a computer program as the difference between the maximum and the minimum QT in any of the 12 leads. CAN was diagnosed when two out of the four classical tests were abnormal.

RESULTS

QTd was not significantly different between controls and patients with either Type 1 or 2 diabetes. Age-adjusted QTd intervals were not significantly different between patients with Types 1 and 2 diabetes (P=.86). For both types of diabetes, no significant differences were found in QTd between patients with and without CAN. Multivariable linear regression analysis, after adjustment for a number of confounding factors, demonstrated a positive association between QTd and duration of diabetes (P=.02) in the group of the patients with Type 1 diabetes. In those with Type 2 diabetes, QTd was associated with age (P=.006) and presence of microalbuminuria (P=.001). In addition, no significant association was found with retinopathy or blood pressure levels.

CONCLUSIONS

Age-adjusted QTd interval was not different between patients with Types 1 and 2 diabetes. CAN is not associated with QTd interval in both types of diabetes. Furthermore, microalbuminuria was found to be the strongest predictor of QTd in patients with Type 2 diabetes. Because long QTd interval predicts cardiac mortality in participants with diabetes, it is suggested that it may be a useful adjuvant index in the evaluation of cardiovascular risk in participants with Type 2 diabetes and microalbuminuria.

Urine albumin excretion and subclinical cardiovascular disease. The Multi-Ethnic Study of Atherosclerosis

We examined the association between urine albumin excretion (UAE) and common and internal carotid artery intima-media thickness (IMT), end-diastolic left ventricular (LV) mass, and coronary artery calcification (CAC) scores using data from the Multi-Ethnic Study of Atherosclerosis (MESA), a population-based study of 6814 adults aged 45 to 85 years without clinical cardiovascular disease (CVD). The mean age of the MESA participants was 62.7 years, 47% were male, and 15% had diabetes mellitus (DM). Sex-specific spot urine albumin/creatinine ratios were used to define 4 UAE categories: normal, high normal, microalbuminuria, and macroalbuminuria. CAC scores were log-transformed after adding 1 to all scores. Mean values of subclinical CVD measures were computed by level of UAE after adjustment for blood pressure, DM, and other covariates. After adjustment for all covariates, geometric mean CAC scores were higher among participants with high normal UAE (8.8; P=0.07), microalbuminuria (9.9; P=0.002), and macroalbuminuria (13.1; P=0.02) compared with normal UAE (7.4), but only microalbuminuria reached statistical significance. Mean LV mass (g/m2.7) was significantly higher in participants with high normal UAE (37.0; P=0.001), microalbuminuria (38.3; P< or =0.0001), and macroalbuminuria (42.3; P< or =0.0001) compared with normal UAE (36.0) after adjustment for all covariates. No significant difference in mean carotid IMT was found after adjustment for all covariates. Similar results were noted in MESA participants with and without DM. In conclusion, higher UAE, including levels below microalbuminuria, may reflect the presence of subclinical CVD among adults without established CVD.

The controversial role of serum uric acid in essential hypertension: relationships with indices of target organ damage

The role of serum uric acid (SUA) in the context of adverse cardiovascular events in hypertensive subjects is controversial. Additionally, the relationship between SUA and indices of target organ damage is not well defined in this setting. Towards this end, we studied 842 consecutive nondiabetic patients with stage I-II essential hypertension (office blood pressure=148/95 mmHg, aged 53.4 years), referred to our outpatient hypertensive unit within a period of 4 years. According to the urinary albumin excretion (UAE), the study population was classified into those with microalbuminuria [MA(+), UAE=20-200 mg/24 h, n=222] and those without MA [MA (-), UAE< 20 mg/24 h, n=620]. Moreover, according to the presence of left ventricular hypertrophy (LVH) the participants were subdivided into two additional groups: [LVH (+), n=305 and LVH (-), n=537]. SUA levels were higher by 0.4 mg/dl, (P=0.04) in group MA (+) compared with the group MA (-), while no difference was observed between groups LVH (+) and LVH (-) (P=NS). In the entire population, SUA was correlated with body mass index (BMI) (r=0.17, P<0.001), waist/hip ratio (r=0.3, P<0.001), office systolic blood pressure (SBP) (r=0.14, P<0.05), triglycerides levels (r=0.25, P<0.001), UAE (r=0.35, P<0.001) and HDL (r=-0.26, P<0.001). Multiple regression analysis demonstrated that SUA was significantly related with BMI, office SBP and UAE (P<0.05). In conclusion, increased SUA levels are associated with MA but not with LVH in essential hypertensive subjects. Whether these inter-relationships may elucidate the clinical positioning of augmented SUA in this setting remains to be clarified in future studies.

Association between chronic kidney disease and coronary artery calcification: the Dallas Heart Study

The hypothesis that chronic kidney disease (CKD) is associated with increased coronary artery calcification (CAC) was tested using data from the Dallas Heart Study, a representative sample of Dallas County residents aged 30 to 65 yr. CKD was defined as presence of microalbuminuria and GFR > or =60 ml/min per 1.73 m(2) (stage 1 to 2), or GFR <60 ml/min per 1.73 m(2) (stage 3 to 5), excluding end-stage kidney disease. Logistic regression was used to examine the association between stages of CKD and CAC scores >10, >100, and >400 versus scores < or =10 compared with no CKD while adjusting for covariates. Analyses were repeated after stratifying by presence of diabetes. The mean age was 43.9 yr, and hypertension and diabetes were noted in 31.0 and 9.8%, respectively. No association was noted between stage 1 to 2 CKD and increased CAC scores. Compared with no CKD, stage 3 to 5 CKD was associated with CAC scores >100 (odds ratio, 2.85; 95% confidence interval, 0.92 to 8.80) and >400 (odds ratio, 8.35; 95% confidence interval, 1.94 to 35.95) in the total population after adjustment for covariates, but these associations were substantially reduced after exclusion of participants with diabetes. Participants with diabetes and stage 3 to 5 CKD had a ninefold increased odds of CAC scores >10 versus scores < or =10 compared with participants with diabetes and without CKD, whereas no association was noted between stage 3 to 5 CKD and CAC scores >10 in the nondiabetic population. In conclusion, stage 3 to 5 CKD is associated with increased CAC scores, but this association may be substantially stronger among adults with diabetes. These findings need to be confirmed in study populations that include adults >65 yr of age and a larger number of CKD cases.

Low-grade inflammation and microalbuminuria in hypertension

Background- Albuminuria and C-reactive protein (CRP), a marker of systemic low-grade inflammation, are frequently elevated in essential hypertension and predict cardiovascular prognosis independent of conventional risk factors. However, in spite of their potentially important links, the interrelationships between the 2 parameters have not been explored in depth in hypertensive patients.

METHODS AND RESULTS

Albuminuria (the mean of 3 overnight urine collections), high-sensitive CRP (hs-CRP), 24-hour blood pressure (BP), weight, lipids, poststimulative (75 g PO) plasma glucose, insulin, and insulin sensitivity by the homeostasis model assessment model were evaluated in 220 never treated, nondiabetic, uncomplicated essential hypertensive men. Albuminuria > or =15 microg/min was defined as microalbuminuria and hs-CRP values above and below median (2.3 mg/L) as high and low, respectively. Concentric left ventricular hypertrophy was diagnosed by echocardiography, and a full-blown metabolic syndrome was identified in presence of hypertension and at least 3 of following: obesity, subclinical hyperglycemia, low high-density lipoprotein (HDL) and high triglycerides. Microalbuminuria was present in 54 patients, 29 with high hs-CRP characterized by higher 24-hour systolic BP, postload glucose, body mass index, lower HDL cholesterol, more frequent metabolic syndrome, concentric LVH, and active smoking than those with either isolated microalbuminuria (n=27) or normoalbuminuria.

CONCLUSIONS

Microalbuminuria accompanied by evidence of subclinical inflammation is a strong correlate of metabolic abnormalities in essential hypertension and identifies a patient subset at very high cardiovascular risk. In contrast, isolated microalbuminuria may represent a distinct pathophysiological condition characterized by a more benign profile and possibly a better prognosis.

Risk factors for heart failure

Despite remarkable therapeutic advances in the management of patients with heart failure (HF), the mortality due to this syndrome remains high. Identifying free-living individuals who are at high risk for developing HF may allow implementing strategies that can prevent HF. Prospective epidemiologic studies have identified several risk factors and risk markers for HF. This article reviews current knowledge regarding conventional and newer risk markers for HF, outlines possible underlying mechanisms for the increased HF risk, and provides a framework for clinical multivariate risk prediction using HF risk factors.

Mechanisms and management of hypertensive heart disease: from left ventricular hypertrophy to heart failure

Hypertensive heart disease (HHD) is a spectrum of abnormalities that represents the accumulation of a lifetime of functional and structural adaptations to increased blood pressure load. Left ventricular hypertrophy (LVH), increasing vascular and ventricular stiffness,and diastolic dysfunction are prominent intermediate features of this syndrome that operate in parallel with ischemic heart disease and ultimately cause heart failure (HF) if inadequately treated. Outcomes in HHD and HF are improved by antihypertensive drugs at any stage of the condition. This review describes an integrated model of the natural history, pathogenesis, and drug treatment of hypertensive heart disease that is consistent with the recommendations of the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, including an important modification to the HF guideline published by the American College of Cardiology and the American Heart Association that includes LVH and diastolic dysfunction as treatable conditions within the HHD-HF continuum.