Uric acid and left ventricular hypertrophy in Japanese men

Uric acid as a cardiorenal mediator: pathogenesis and mechanistic insights

Introduction: The role of serum uric acid as a connector in cardiorenal interactions has been long debated and studied extensively in the past decade. Epidemiological, and clinical data suggest that hyperuricemia may be an independent risk factor as well as a strong predictor of morbidity and mortality in cardiovascular diseases (CVD) and renal diseases. New data suggesting that urate lowering therapies may improve outcomes in cardiovascular diseases have generated interest.Areas Covered: This review attempts to summarize the pathophysiological mechanisms by which hyperuricemia causes cardiorenal dysfunction. It also provides a summary of the recent evidence for urate lowering therapies and the possible underlying mechanisms which lead to cardiovascular benefits. This was a narrative review with essential references or cross references obtained via expert opinion.Expert Opinion: Emphasis on newer drugs that address the cardio-renal metabolic axis and the relation to their effects on uric acid may help further elucidate underlying mechanisms responsible for their cardiovascular and renal benefits. Once these benefits are well established, we will be able to come up with guidelines for targeting hyperuricemia. This can potentially lead to a change in clinical practice and can possibly lead to improved cardiovascular and renal outcomes.

Effect of Long-Term Allopurinol Therapy on Left Ventricular Mass Index in Patients with Ischemic Heart Disease; A Cross-Sectional Study

Background

Left ventricular hypertrophy (LVH), as assessed by measurement of left ventricular mass (LVM), is one of the most important cardiovascular risk factors. It is commonly present in patients with ischemic heart disease (IHD), irrespective of the level of blood pressure; recently, oxidative stress has been shown to be an important factor in its development. The question then arises: can this risk factor be modified by antioxidant treatment (e.g., with allopurinol, a xanthine oxidase inhibitor)?

Methods

This is an observational study with a cross-sectional design which explored the association between long-term (>12 months) allopurinol therapy and LV mass index (LVMI) as well as geometry in patients generally receiving standard treatments for IHD. The primary endpoint was LVMI measurement (by 2D-echocardiography) and secondary endpoints included the association of allopurinol use with LV function (ejection fraction), blood pressure, glycemic control, and lipid profile.

Results

Ninety-six patients on standard anti-ischemic drug treatment (control group) and 96 patients who were additionally taking allopurinol (minimum dose 100 mg/day) were enrolled. Both groups were matched for age, sex, height, and co-morbidities, but poorer kidney function in the allopurinol group required further sub-group analysis based on renal function. Allopurinol treatment was associated with the lowest LVMI in the patients with normal serum creatinine (median LVMI; 70.5 g/m²): corresponding values were 76.0 and 87.0 in the control group with, respectively, normal and elevated serum creatinine, and 89.5 in the allopurinol group with elevated serum creatinine (P=0.027). In addition, allopurinol was associated with better glycemic control (HbA1c) with a difference of 0.8% (95% CI; 1.3, 0.2) (P=0.004) as compared with control patients.

Conclusion

In our population, treatment with allopurinol (presumably because of its anti-oxidant properties) has shown a tendency to be associated with smaller LVM in IHD patients with normal serum creatinine, along with better glycemic control.

Clinical Characteristics Associated with Electrocardiographic Left Ventricular Hypertrophy in Clinical Normotensives without a History of Hypertension: a Cross-Sectional Study

Background

Methods

Results

Conclusion

Gender-Related Association of Serum Uric Acid Levels with Premature Ventricular Contraction

In this study, we aim to investigate the association of serum uric acid (SUA) with the prevalence of premature ventricular contraction (PVC). The relationship between SUA and the prevalence of PVC in 98,965 subjects (79,034 male subjects, mean age: 51.9 ± 12.6 years old) in the Kailuan cohort study (n = 101,510, age range: 18-98 years) from June 2006 to October 2007 was investigated. These subjects were divided into five groups on the basis of their SUA levels. A multivariate logistic regression model was constructed to evaluate the association between SUA and the prevalence of PVC. The prevalence of PVC was 1.1% in all subjects, 1.1% in male subjects, and 1.0% in female subjects. Compared with the first quintile of SUA, the odds ratio (OR) and 95% confidence interval (95% CI) of other quintiles were 1.33 (1.05-1.69), 1.14 (0.90-1.46), 1.37 (1.08-1.74), and 1.63 (1.30-2.06) in male subjects; 1.12 (0.68-1.87), 1.27 (0.77-2.09), 1.45 (0.90-2.36), and 1.33 (0.81-2.18) in female subjects; and 1.30 (1.04-1.61), 1.20 (0.96-1.50), 1.33 (1.07-1.66), and 1.57 (1.26-1.95) for all subjects. The correlation between SUA and the prevalence of PVC was significant in all subjects and in male subjects, but not in female subjects. We demonstrated that SUA was apparently associated with the prevalence of PVC. The significant relationship between SUA and PVC identified in male subjects suggests the potential involvement of a gender-specific mechanism. Prospective studies are needed to further corroborate our results.

Assessment of cardiovascular risk profile based on measurement of tophus volume in patients with gout

Hyperuricemia and gout are associated with increased risk of cardiovascular disease and metabolic syndrome. The aim of this study was to evaluate the correlation of total tophus volumes, measured using dual-energy computed tomography, with cardiovascular risk and the presence of metabolic syndrome. Dual-energy computed tomography datasets from 91 patients with a diagnosis of gout were analyzed retrospectively. Patients who received urate lowering therapy were excluded to avoid the effect on tophus volume. The total volumes of tophaceous deposition were quantified using automated volume assessment software. The 10-year cardiovascular risk using the Framingham Risk Score and metabolic syndrome based on the Third Adult Treatment Panel criteria were estimated. Fifty-five and 36 patients with positive and negative dual-energy computed tomography results, respectively, were assessed. Patients with positive dual-energy computed tomography results showed significantly higher systolic blood pressure, diastolic blood pressure, fasting glucose, and higher prevalence of chronic kidney disease, compared with those with negative dual-energy computed tomography results. The total tophus volumes were significantly correlated with the Framingham Risk Score, and the number of metabolic syndrome components (r = 0.22 and p = 0.036 and r = 0.373 and p < 0.001, respectively). The total tophus volume was one of the independent prognostic factors for the Framingham Risk Score in a multivariate analysis. This study showed the correlation of total tophus volumes with cardiovascular risk and metabolic syndrome-related comorbidities. A high urate burden could affect unfavorable cardiovascular profiles.

Serum uric acid and the relationship with subclinical organ damage in adults

AIMS

Elevated serum uric acid (SUA) is often present in conditions associated with increased cardiovascular risk yet it is not recognized as a marker of risk. We evaluated whether SUA was associated with evidence of early markers of cardiovascular risk factor including subclinical early organ damage, sympathetic tone and metabolic profile in a healthy population with a high prevalence of obesity.

MATERIAL AND METHODS

Data from 281 patients (175 women and 106 men, mean age: 35.5 ± 0.8 years, mean BMI: 33.2 ± 0.5 kg/m) were retrieved from a database. All participants were healthy, nonsmoker and free of medication. Available data included metabolic profile, muscle sympathetic nervous activity (MSNA, microneurography), endothelial function (pulse amplitude tonometry, augmentation index), estimated glomerular filtration rate (eGFR) and echocardiography.

RESULTS

With participants grouped into sex-adjusted tertiles of SUA, those in the third tertile of SUA had increased waist circumference, worse metabolic profile (fasting glucose, total cholesterol, triglycerides and HDL), elevated MSNA, decreased endothelial function, increased augmentation index and decreased eGFR compared with those in the first tertile of SUA. In multiple regression analysis adjusted for age, sex, BMI and ethnicity, SUA was independently associated with waist circumference, low-density lipoprotein, triglycerides, augmentation index, MSNA and eGFR, providing a combined adjusted R = 0.599 or 60% of the overall variance.

CONCLUSION

In a healthy population with a high proportion of obesity, SUA is associated with measures of metabolic, end-organ damage and sympathetic tone indicating the potential value of SUA as a marker of early cardiovascular disease development.

Increased Serum Uric Acid Level Is a Risk Factor for Left Ventricular Hypertrophy but Not Independent of eGFR in Patients with Type 2 Diabetic Kidney Disease

BACKGROUND

Although the relation between serum uric acid (SUA) and left ventricular hypertrophy (LVH) has been studied for decades, however, their association remains debatable.

METHODS

This is a retrospective study in which a total of 435 hospitalized Chinese patients with type 2 DKD were enrolled. The subjects were stratified into quartiles according to SUA level. LVH was assessed by two-dimensional guided M-mode echocardiography.

RESULTS

There was a significant increase in the prevalence of LVH in patients with type 2 DKD across SUA quartiles (28.9, 26.5, 36.1, and 49.5%; p < 0.001). The Spearman analysis indicated that SUA was positively correlated to LVMI and negatively correlated to eGFR. The logistic regression analysis revealed that the odd ratio for LVH in the highest SUA quartile was 2.439 (95% CI 1.265-4.699; p = 0.008; model 1) or 2.576 (95% CI 1.150-5.768; p = 0.021; model 2) compared with that in the lowest SUA quartile. However, there was no significant increased risk of LVH in the subjects with the highest SUA quartile after adjusting the eGFR (OR = 1.750; 95% CI 0.685-4.470; p = 0.242; model 3).

CONCLUSIONS

In selected population, such as type 2 DKD, the elevated SUA level is positively linked with the increased risk of LVH, but this relationship is not independent of eGFR.

Sex-specific association between serum uric acid and prolonged corrected QT interval: Result from a general rural Chinese population

Recently, it has been found that high level of serum uric acid (SUA) is causally related to sudden cardiac death (SCD). We examined the sex-specific associations of SUA with prolonged heart rate-corrected QT (QTc) interval in a general Chinese population.A large sample of 11,206 Chinese research participants aged 35 years and older was recruited from rural areas of Liaoning Province during 2012 to 2013. SUA were divided into quartiles separated for males and females. Prolonged QTc interval, assessed by the Bazett formula, was defined as cut points of 460 ms or longer in females and 450 ms or longer in males. Mean (+/- standard deviation) QTc intervals were 422.1 ± 24.2 ms among 5104 males and 436.1 ± 23.5 ms among 6102 females, respectively. In both sexes, SUA showed significant correlations with QTc interval (both P < 0.001). Among male participants, the highest quartile of SUA (>379 μmol/L) was related to an increased risk for prolonged QTc interval (odds ratios: 1.402, 95% confidence interval: 1.073-1.831) compared to the lowest quartile (≤276 μmol/L) after fully adjustment. However, there were no significant relationships between SUA and prolonged QTc interval among females in all the models.Males with high SUA are prone to a higher risk for prolonged QTc interval. This study provides novel explanation for population-based findings on SUA and SCD, as well as important implications for management strategies for hyperuricemic patients in clinical practice.

Evaluation of cardiovascular risk in stages of gout by a complex multimodal ultrasonography

The aim of our work was to assess ultrasound features of cardiovascular (CV) risk in stages of gout. Cross-sectional complex multimodal ultrasound study of 169 age-matched patients, with similar distribution of arterial hypertension, diabetes mellitus, obesity and chronic renal failure, was divided into four groups: 41 with asymptomatic hyperuricemia, 52 gout without tophi, 42 gouty tophi and 34 controls with osteoarthritis. Parameters independently associated with CV risk were measured: renal resistive index (RRI), left ventricular mass index (LVMi), mitral annulus early diastolic velocity (e'), intima-media thickness (IMT) and common carotid artery resistive index (CCARI). Multivariate analyses were performed to evaluate the impact of gout stages and CV risk factors on ultrasound alterations. Gouty tophi increased the risk of having IMT >0.90 mm with an OR 11.51 (95 % CI 2.32-57.21, p = 0.003), gout without tophi raised the risk with an OR 6.25 (95 % CI 1.37-28.44, p = 0.018), while asymptomatic hyperuricemia had no effect on IMT. The category of CCARI >0.70 was influenced by tophi with an OR 11.18 (95 % CI 2.61-47.83, p = 0.001) and by arterial hypertension with an OR 3.22 (95 % CI 1.11-9.36, p = 0.032). Neither asymptomatic hyperuricemia nor gout without tophi modified the development of abnormally high CCARI. Gout stages had no impact on LVMi, e' and RRI. Tophi are related to worsened ultrasonographic parameters evaluating target organs in gout, relative to earlier stages of the disease. They create a strong risk of carotid arteries' changes even beyond arterial hypertension.

Gender-related differences in the association between serum uric acid and left ventricular mass index in patients with obstructive hypertrophic cardiomyopathy

BACKGROUND

Serum uric acid (SUA) is associated with left ventricular hypertrophy in a wide spectrum of study population. However, whether this association exists in patients with hypertrophic cardiomyopathy (HCM, including obstructive HCM), and if present, whether gender has any impact on this association, remains unknown.

METHODS

A total of 161 patients with obstructive HCM (age 47.2 ± 10.8 years, 99 (62 %) men) were included in this study. All patients underwent extensive clinical, laboratory, echocardiographic, and cardiac magnetic resonance (CMR) imaging examinations. Left ventricular mass index (LVMI) was assessed using CMR.

RESULTS

The mean value of SUA was 353.4 ± 87.5 μmol/L. Both SUA levels (381.2 ± 86.4 vs. 309.0 ± 69.3 μmol/L, p < 0.001) and LVMI (96.2 ± 32.1 vs. 84.4 ± 32.4 g/m(2), p = 0.025) were significantly higher in men than in women. LVMI increased progressively across sex-specific tertiles of SUA in women (p = 0.030), but not in men (p = 0.177). SUA was positively correlated with LVMI in female patients (r = 0.372, p = 0.003), but not in males (r = 0.112, p = 0.269). On multivariate linear regression analysis, SUA was independently associated with LVMI in females (β = 0.375, p = 0.002), but not in males.

CONCLUSIONS

SUA levels are significantly and independently associated with LVMI in women with obstructive HCM, but not in men. Our findings imply the potential significance of urate-lowering regimens in female patients with obstructive HCM.

Elevated uric acid and obesity-related cardiovascular disease risk factors among hypertensive youth

BACKGROUND

Uric acid (UA) is associated with high blood pressure in adolescents and with left ventricular hypertrophy (LVH) and cardiovascular disease (CVD) in adults. We sought to determine if UA is independently associated with CVD risk factors and left ventricular mass (LVM) over time in hypertensive youth.

METHODS

This was a 1-year prospective observational study of hypertensive children aged 3-19 years. Cross-sectional and longitudinal associations of serum UA with CVD risk factors and LVM were explored.

RESULTS

Of the 49 children who completed both the baseline and 12-month assessments, at baseline the mean age was 13.8 years and mean UA was 5.5 mg/dL; 24% had elevated UA, 51% were overweight/obese and 39% had LVH. Measures of adiposity, low high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, LVM and LVH were all significantly associated with elevated UA at baseline, but not with change over time. Each 1 mg/dL increase in baseline UA was associated with a 2.5 g/m(2.7) increase in the LVM index at follow-up (95% confidence interval 0.64, 4.39; p = 0.01); after adjustment for age, sex, race, body mass index z-score, change in UA, time, blood pressure and medication use, this association was no longer significant.

CONCLUSIONS

Hypertensive children with elevated UA have a higher prevalence of obesity-related CVD risk factors. Among hypertensive children, UA may be a marker of adiposity and not an independent CVD risk factor.

Gout, not hyperuricemia alone, impairs left ventricular diastolic function

Introduction

Gout is a common metabolic disorder characterized by hyperuricemia and chronic inflammation. Previous studies show that hyperuricemia accelerates the occurrence and worsening of cardiovascular disease due to LV remodeling. However, it is still unclear whether hyperuricemia is the sole contributor to organic heart remodeling in patients with gout. In addition, there is a paucity of data regarding the association between LV diastolic function and gout. The objective of this study was to investigate the effects of gout on LV diastolic function.

Methods

A total of 173 patients were divided into tertiles based on the following serum uric acid (UA) levels: 1) serum UA ≤ 6.5 mg/dL (n = 54), 2) serum UA >6.5 to ≤8.5 mg/dL (n = 59), and 3) serum UA > 8.5 mg/dL (n = 60).Patients underwent a comprehensive Doppler-echocardiography examination to evaluate LV volume, systolic and diastolic function, and left atrial (LA) volume.

Results

LV diastolic parameters, including diastolic peak early transmitral flow velocity (E), late transmitral flow velocity (A), E/A, peak early diastolic mitral annular velocity (Em), late diastolic annular velocity (Am), Em/Am, E/Em, maximal LA volume index (LAVi) and prevalence of moderate to severe LV diastolic dysfunction were not significantly different between the three groups. Among the population being studied, 108 individuals received a gout diagnosis. Gout patients had greater LV end-systolic dimensions (27.08 ± 4.38 mm, p = 0.006), higher LV mass index (107.18 ± 29.51 g/m², p < 0.001), higher E/Em (10.07 ± 2.91, p = 0.008), and larger maximal LAVi (16.96 ± 7.39 mL/m², p < 0.001) than patients without gout. The prevalence of moderate to severe LV diastolic dysfunction was higher in patients with gout (23 %, p = 0.02).

Conclusions

Gout, not hyperuricemia alone, is associated with LV diastolic dysfunction and LA volume enlargement.

Serum uric acid and other short-term predictors of electrocardiographic alterations in the Brisighella Heart Study cohort

INTRODUCTION

Recent studies show that serum uric acid (SUA) is a predictor of atrial fibrillation, while its association with other kinds of arrhythmias is not yet established. We aimed to evaluate the incidence of the most common electrocardiographic alterations in a relatively large sample of general population and their association with SUA.

MATERIALS AND METHODS

We selected a Brisighella Heart Study cohort sample of 1557 subjects, consecutively visited in the 2004 and 2008 surveys, in a setting of primary prevention for cardiovascular disease and without a known diagnosis of arrhythmia or left ventricular hypertrophy, excluding subjects affected by gout or taking any antihyperuricemic agent or drugs able to interfere with the QT interval. A step-wise Cox regression analysis was used to determine the independent prognostic significance of age, gender, physical activity, smoking, body mass index (BMI), fasting plasma glucose, mean arterial pressure (MAP), heart rate, LDL-cholesterol, HDL-cholesterol, triglycerides, SUA and eGFR on ECG alterations during a 4-year follow-up.

RESULTS

No one of the considered variables was associated with the incident diagnosis of sinus tachycardia and sinus bradycardia. SUA predicted incident tachyarrhythmias, Q waves and ECG signs of left ventricular hypertrophy; age, female sex and active smoking predicted incident tachyarrhythmias; male sex, active smoking and LDL-cholesterol predicted incident ECG signs of previous myocardial infarction; BMI and MAP predicted incident ECG-diagnosed left ventricular hypertrophy.

CONCLUSION

In a cohort of general population, SUA seems to be a significant middle-term predictor of electrocardiographically diagnosed myocardial infarction, left ventricular hypertrophy and tachyarrhythmias.

Cross-sectional analysis of serum calcium levels for associations with left ventricular hypertrophy in normocalcemia individuals with type 2 diabetes

Background

Left ventricular hypertrophy (LVH) is prevalent in patients with type 2 diabetes mellitus (T2DM). Recent studies show that an increase in albumin-adjusted serum calcium level is associated with an elevated risk of T2DM. We speculate that increased serum calcium levels in T2DM patients are related to LVH prevalence.

Methods

In this echocardiographic study, 833 normocalcemia and normophosphatemia patients with T2DM were enrolled. The associations between serum calcium and metabolic parameters, left ventricular mass index (LVMI), as well as the rate of LVH were examined using bivariate linear correlation, multivariate linear regression and logistic regression, respectively. The predictive performance of serum calcium for LVH was evaluated using the area under the receiver operating characteristic curve (AUC).

Results

Patients with LVH have significantly higher serum calcium than those without LVH. Serum calcium was positively associated with total cholesterol, triglycerides, low-density lipoprotein cholesterol, serum uric acid, HOMA-IR and fasting plasma glucose. Multivariate linear regression analysis demonstrated that serum calcium was independently associated with LVMI (p < 0.001). In comparison with patients in the lowest serum calcium quartile, the odds ratio (OR) for LVH in patients in the highest quartile was 2.909 (95% CI 1.792-4.720; p < 0.001). When serum calcium was analyzed as a continuous variable, per 1 mg/dl increase, the OR (95% CI) for LVH was [2.400 (1.552-3.713); p < 0.001]. Serum calcium can predict LVH (AUC = 0.617; 95% CI (0.577-0.656); p < 0.001).

Conclusions

Albumin-adjusted serum calcium is associated with an increased risk of LVH in patients with T2DM.

Uric Acid and Cardiovascular Events: A Mendelian Randomization Study

Obesity and diets rich in uric acid-raising components appear to account for the increased prevalence of hyperuricemia in Westernized populations. Prevalence rates of hypertension, diabetes mellitus, CKD, and cardiovascular disease are also increasing. We used Mendelian randomization to examine whether uric acid is an independent and causal cardiovascular risk factor. Serum uric acid was measured in 3315 patients of the Ludwigshafen Risk and Cardiovascular Health Study. We calculated a weighted genetic risk score (GRS) for uric acid concentration based on eight uric acid-regulating single nucleotide polymorphisms. Causal odds ratios and causal hazard ratios (HRs) were calculated using a two-stage regression estimate with the GRS as the instrumental variable to examine associations with cardiometabolic phenotypes (cross-sectional) and mortality (prospectively) by logistic regression and Cox regression, respectively. Our GRS was not consistently associated with any biochemical marker except for uric acid, arguing against pleiotropy. Uric acid was associated with a range of prevalent diseases, including coronary artery disease. Uric acid and the GRS were both associated with cardiovascular death and sudden cardiac death. In a multivariate model adjusted for factors including medication, causal HRs corresponding to each 1-mg/dl increase in genetically predicted uric acid concentration were significant for cardiovascular death (HR, 1.77; 95% confidence interval, 1.12 to 2.81) and sudden cardiac death (HR, 2.41; 95% confidence interval, 1.16 to 5.00). These results suggest that high uric acid is causally related to adverse cardiovascular outcomes, especially sudden cardiac death.

Uric acid promotes left ventricular diastolic dysfunction in mice fed a Western diet

The rising obesity rates parallel increased consumption of a Western diet, high in fat and fructose, which is associated with increased uric acid. Population-based data support that elevated serum uric acids are associated with left ventricular hypertrophy and diastolic dysfunction. However, the mechanism by which excess uric acid promotes these maladaptive cardiac effects has not been explored. In assessing the role of Western diet-induced increases in uric acid, we hypothesized that reductions in uric acid would prevent Western diet-induced development of cardiomyocyte hypertrophy, cardiac stiffness, and impaired diastolic relaxation by reducing growth and profibrotic signaling pathways. Four-weeks-old C57BL6/J male mice were fed excess fat (46%) and fructose (17.5%) with or without allopurinol (125 mg/L), a xanthine oxidase inhibitor, for 16 weeks. The Western diet-induced increases in serum uric acid along with increases in cardiac tissue xanthine oxidase activity temporally related to increases in body weight, fat mass, and insulin resistance without changes in blood pressure. The Western diet induced cardiomyocte hypertrophy, myocardial oxidative stress, interstitial fibrosis, and impaired diastolic relaxation. Further, the Western diet enhanced activation of the S6 kinase-1 growth pathway and the profibrotic transforming growth factor-β1/Smad2/3 signaling pathway and macrophage proinflammatory polarization. All results improved with allopurinol treatment, which lowered cardiac xanthine oxidase as well as serum uric acid levels. These findings support the notion that increased production of uric acid with intake of a Western diet promotes cardiomyocyte hypertrophy, inflammation, and oxidative stress that lead to myocardial fibrosis and associated impaired diastolic relaxation.

Allopurinol and progression of CKD and cardiovascular events: long-term follow-up of a randomized clinical trial

BACKGROUND

Asymptomatic hyperuricemia increases renal and cardiovascular (CV) risk. We previously conducted a 2-year, single-blind, randomized, controlled trial of allopurinol treatment that showed improved estimated glomerular filtration rate and reduced CV risk.

STUDY DESIGN

Post hoc analysis of a long-term follow-up after completion of the 2-year trial.

SETTING & PARTICIPANTS

113 participants (57 in the allopurinol group and 56 in the control group) initially followed up for 2 years and 107 participants followed up to 5 additional years.

INTERVENTION

Continuation of allopurinol treatment, 100mg/d, or standard treatment.

OUTCOME

Renal event (defined as starting dialysis therapy and/or doubling serum creatinine and/or ≥50% decrease in estimated estimated glomerular filtration rate) and CV events (defined as myocardial infarction, coronary revascularization or angina pectoris, congestive heart failure, cerebrovascular disease, and peripheral vascular disease).

RESULTS

During initial follow-up, there were 2 renal and 7 CV events in the allopurinol group compared with 6 renal and 15 CV events in the control group. In the long-term follow-up period, 12 of 56 participants taking allopurinol stopped treatment and 10 of 51 control participants received allopurinol. During long-term follow-up, an additional 7 and 9 participants in the allopurinol group experienced a renal or CV event, respectively, and an additional 18 and 8 participants in the control group experienced a renal or CV event, respectively. Thus, during the initial and long-term follow-up (median, 84 months), 9 patients in the allopurinol group had a renal event compared with 24 patients in the control group (HR, 0.32; 95% CI, 0.15-0.69; P=0.004; adjusted for age, sex, baseline kidney function, uric acid level, and renin-angiotensin-aldosterone system blockers). Overall, 16 patients treated with allopurinol experienced CV events compared with 23 in the control group (HR, 0.43; 95% CI, 0.21-0.88; P=0.02; adjusted for age, sex, and baseline kidney function).

LIMITATIONS

Small sample size, single center, not double blind, post hoc follow-up and analysis.

CONCLUSIONS

Long-term treatment with allopurinol may slow the rate of progression of kidney disease and reduce CV risk.

Hyperuricemia is independently associated with left ventricular hypertrophy in post-menopausal women but not in pre-menopausal women in rural Northeast China

The aim of this article is to estimate the relationship between hyperuricemia and left ventricular hypertrophy (LVH) and to investigate whether menopause was associated with the relationship between hyperuricemia and LVH. This survey was conducted from July 2012 to August 2013. A total of 6029 women (3508, 58.2% were post-menopause) from the rural Northeast China were randomly selected and examined. LVH was defined using the 2007 Guidelines for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). Age, body mass index, glucose, estimated glomerular filtration rate and lipid level were significantly correlated with serum uric acid level. LVH showed a gradual increase in accordance with the serum uric acid level in entire study population (<4.0 mg/dL, 11.4%; 4 to <5 mg/dL, 14.9%; 5 to <6 mg/dL, 18.9%; ≥6 mg/dL, 27.4%; p < 0.001). Multivariate analysis revealed that hyperuricemia was a significantly independent risk factor for LVH in post-menopausal women [OR (95% CI): 1.367 (1.026, 1.821)], but not in pre-menopausal women [OR (95% CI): 1.290 (0.669, 2.486)]. These findings suggested that hyperuricemia can be used as a risk marker of LVH in a female population and, in particular, as an independent risk factor in post-menopausal women but not in pre-menopausal women.

Relative risks of chronic kidney disease for mortality and end-stage renal disease across races are similar

Some suggest race-specific cutpoints for kidney measures to define and stage chronic kidney disease (CKD), but evidence for race-specific clinical impact is limited. To address this issue, we compared hazard ratios of estimated glomerular filtration rates (eGFR) and albuminuria across races using meta-regression in 1.1 million adults (75% Asians, 21% Whites, and 4% Blacks) from 45 cohorts. Results came mainly from 25 general population cohorts comprising 0.9 million individuals. The associations of lower eGFR and higher albuminuria with mortality and end-stage renal disease (ESRD) were largely similar across races. For example, in Asians, Whites, and Blacks, the adjusted hazard ratios (95% confidence interval) for eGFR 45-59 versus 90-104 ml/min per 1.73 m(2) were 1.3 (1.2-1.3), 1.1 (1.0-1.2), and 1.3 (1.1-1.7) for all-cause mortality, 1.6 (1.5-1.7), 1.4 (1.2-1.7), and 1.4 (0.7-2.9) for cardiovascular mortality, and 27.6 (11.1-68.7), 11.2 (6.0-20.9), and 4.1 (2.2-7.5) for ESRD, respectively. The corresponding hazard ratios for urine albumin-to-creatinine ratio 30-299 mg/g or dipstick 1+ versus an albumin-to-creatinine ratio under 10 or dipstick negative were 1.6 (1.4-1.8), 1.7 (1.5-1.9), and 1.8 (1.7-2.1) for all-cause mortality, 1.7 (1.4-2.0), 1.8 (1.5-2.1), and 2.8 (2.2-3.6) for cardiovascular mortality, and 7.4 (2.0-27.6), 4.0 (2.8-5.9), and 5.6 (3.4-9.2) for ESRD, respectively. Thus, the relative mortality or ESRD risks of lower eGFR and higher albuminuria were largely similar among three major races, supporting similar clinical approach to CKD definition and staging, across races.

Impact of gout on left atrial function: a prospective speckle-tracking echocardiographic study

The purpose of our study was to evaluate the left ventricular (LV) and left atrial (LA) function in patients with gout. A total of 173 patients underwent a comprehensive Doppler-echocardiography examination. Participants were divided into four groups–Stage 0: control (n = 35), Stage I: asymptomatic hyperuricemia (n = 30), Stage II: gouty arthritis without tophi (n = 58), and Stage III: tophaceous gout (n = 50). Serum uric acid levels were not significantly different between stage I, II and III. Stage III patients demonstrated a higher ratio of the transmitral and myocardial peak early diastolic velocities (E/Em) (10.50±3.18 vs. 8.58±2.07; P = 0.008), and larger maximal LA volume index (LAVi) (29.60±9.89 vs. 20.07±4.76 ml/m²; P<0.001) compared with controls. Stage III patients had decreased LV global longitudinal systolic strain (LVε) compared with controls (−20.2±3.06 vs. −21.79±2.27; P = 0.002). Stage III patients also had decreased peak atrial longitudinal strain rate during ventricular systole (ALSR_syst), peak atrial longitudinal strain rate during ventricular early diastole (ALSR_early), and peak atrial longitudinal strain rate during ventricular late diastole (ALSR_late) compared with controls (1.73±0.48 vs. 2.05±0.55 1/s, −1.44±0.53 vs. −2.07±0.84 1/s, −2.07±0.7 vs. −2.66±0.91 1/s, respectively; all P<0.005). Multiple regression analysis revealed severity of gout had an independent negative impact on LA pump function (ALSR_late). In conclusion, gout caused LV diastolic dysfunction, LV subclinical systolic dysfunction and LA reservoir, conduit, and booster pump dysfunction.

Elevated serum uric acid is associated with angiotensinogen in obese patients with untreated hypertension

This study investigated the correlation between elevated serum uric acid (SUA) and angiotensinogen in obesity patients with hypertension. A total of 162 obese and 162 nonobese men with hypertension were recruited in this study. Plasma angiotensinogen levels were measured by enzyme-linked immunosorbent assay. Fasting insulin (FINS) was evaluated by radioimmunoassay. Compared with nonobese patients, obese patients exhibited higher levels of angiotensinogen, FINS, and homeostasis model assessment index-insulin resistance (HOMA-IR) (P<.001 for all). Moreover, these indexes significantly increased in obese patients in the highest tertile of SUA when compared with those in the lowest tertile of SUA (P<.001, P=.002, P=.007, respectively). In the obese group, SUA levels were significantly related to angiotensinogen, FINS, and HOMA-IR, respectively. Furthermore, it was demonstrated that obesity × uric acid was an independent contributor to angiotensinogen (β=0.257, P<.001). In conclusion, elevated SUA is strongly related to angiotensinogen in an obesity-dependent manner in hypertension.

Serum uric acid is associated with the left ventricular mass index in males of a general population

The association of serum uric acid (UA) with left ventricular hypertrophy (LVH) remains controversial. We investigated this issue in a general population. Participants consisted of 1,943 subjects (774 males and 1,169 females) aged over 40 years, living in Tanushimaru (a Japanese cohort of the Seven Countries Study). Serum UA and other biochemistry parameters were determined by a standard analytical technique. All individuals underwent anthropometric measurements and 2-dimensional echocardiography. Because serum UA levels are much higher in males than in females, they were analyzed separately. When LV mass index (LVMI) levels were stratified according to tertile as low (≤ 80 cm(2): n = 261), middle (81-103 cm(2): n = 261), and high (≥ 104 cm(2): n = 252) in males, there were significant relationships between LVMI and UA, in addition to age, body mass index, systolic blood pressure, medication for hypertension, triglycerides, and alcohol intake. Multiple stepwise regression analysis revealed LVMI was significantly associated with systolic BP (P < 0.0001), medication for hypertension (P < 0.0001), UA (P = 0.003), BMI (P = 0.019), and alcohol intake (P = 0.038) in males. In females, LVMI was not associated with UA. In a multiple logistic regression analysis, a significantly higher odds ratio of LVH (odds ratio: 1.77, 95%CI: 1.01-3.09, P < 0.05) was observed for males in the highest UA tertile versus the lowest UA tertile after adjustments for confounding factors, but not for females. In this cross-sectional study, there was a clear difference in the relation of UA and LVH between males and females. High serum UA was significantly and independently associated with LVH evaluated by echocardiography in only males of a general population.

Serum uric acid is associated with left ventricular hypertrophy independent of serum parathyroid hormone in male cardiac patients

Background

Several studies have shown that serum uric acid (UA) is associated with left ventricular (LV) hypertrophy. Serum levels of parathyroid hormone (PTH), which has bbe shown to be correlated with UA, is also known to be associated with cardiac hypertrophy; however, whether the association between UA and cardiac hypertrophy is independent of PTH remains unknown.

Purpose

We investigated whether the relationship between serum uric acid (UA) and LV hypertrophy is independent of intact PTH and other calcium-phosphate metabolism-related factors in cardiac patients.

Methods and Results

In a retrospective study, the association between UA and left ventricular mass index was assessed among 116 male cardiac patients (mean age 65±12 years) who were not taking UA lowering drugs. The median UA value was 5.9 mg/dL. Neither age nor body mass index differed significantly among the UA quartile groups. Patients with higher UA levels were more likely to be taking loop diuretics. UA showed a significant correlation with intact PTH (R = 0.34, P<0.001) but not with other calcium-phosphate metabolism-related factors. Linear regression analysis showed that log-transformed UA showed a significant association with left ventricular mass index, and this relationship was found to be significant exclusively in patients who were not taking loop and/or thiazide diuretics. Multivariate logistic regression analysis showed that log-transformed UA was independently associated with LV hypertrophy with an odds ratio of 2.79 (95% confidence interval 1.48–5.28, P = 0.002 per one standard deviation increase).

Conclusions

Among cardiac patients, serum UA was associated with LV hypertrophy, and this relationship was, at least in part, independent of intact PTH levels, which showed a significant correlation with UA in the same population.

Uric acid increases the incidence of ventricular arrhythmia in patients with left ventricular hypertrophy

BACKGROUNDS

Elevated uric acid (UA) level is reported to be related to the development of left ventricular hypertrophy (LVH) which is associated with high incidence of ventricular tachycardia (VT) and sudden cardiac death. However, little is known about the association between serum UA levels and the occurrence of VT. Thus, we examined the relationship between serum UA levels and the appearance of VT in patients with LVH.

METHODS

The study subjects consisted of 167 patients (110 males, mean age 67.4 ± 12.7 years) with LVH detected by echocardiography. These patients were divided into two groups based on whether VT was presented (defined by more than 5 beats, n = 27) or not (n = 140) by 24-hour Holter ECG monitoring. Left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVDd), the E/A ratio and deceleration time of transmitral flow velocity were assessed by echocardiography in each group. In addition, blood urea nitrogen (BUN), creatinine, estimated glomerular filtration rate (eGFR), sodium, potassium, hemoglobin, total bilirubin and UA were compared in each group.

RESULTS

Echocardiographic findings did not show the difference between the two groups. However, BUN and UA levels in the VT group were significantly higher than those in the Non-VT group (p < 0.01). eGFR was significantly lower in the VT group than that in the Non-VT group (p < 0.01). A multivariate logistic regression analysis identified the UA level as an independent predictive factor for the occurrence of VT (odds ratio 1.61, 95% confidence interval 1.1-2.2, p < 0.01).

CONCLUSIONS

These results suggest that serum UA level is a useful marker for predicting ventricular arrhythmias in patients with LVH.

Sex differences in the association between serum uric acid levels and cardiac hypertrophy in patients with chronic kidney disease

Several studies have documented an association between serum uric acid (SUA) concentration and cardiac hypertrophy in hypertensive patients; however, the association remains unclear in chronic kidney disease (CKD) patients. If there is an association between SUA and hypertrophy in these patients, it is unknown whether the association is different between men and women. Our aim in this study is to determine whether SUA is associated with cardiac hypertrophy in CKD patients, focusing on any sex differences. Two hundred sixteen CKD patients (117 men and 99 women) were enrolled in this cross-sectional study. Patients prescribed uric acid-lowering agents and those with congestive heart failure, valvular heart disease, or ischemic heart disease were excluded from this study. Left ventricular mass index (LVMI) and left ventricular hypertrophy (LVH) were assessed using echocardiography. The prevalence of LVH was 58% in men and 47% in women. In multivariate linear regression analysis, SUA levels did not correlate with LVMI in men, whereas SUA was independently associated with LVMI in women (β=0.27, P=0.02). Multivariate logistic regression analysis also revealed that diabetes mellitus (odds ratio (OR), 4.41; P=0.01) was associated with LVH in men, whereas age (OR, 1.13; P<0.01), hypertension (OR, 7.38; P=0.03) and SUA (OR, 1.91; P=0.03) were associated with LVH in women. In female CKD patients, SUA levels were associated with LVMI and LVH, whereas there was no association in male patients. These observations suggest that an association between SUA levels and the development of cardiac hypertrophy is more likely in women than in men.

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.

The relationship between training status, blood pressure and uric acid in adults and elderly

Background

Hypertension can be generated by a great number of mechanisms including elevated uric acid (UA) that contribute to the anion superoxide production. However, physical exercise is recommended to prevent and/or control high blood pressure (BP). The purpose of this study was to investigate the relationship between BP and UA and whether this relationship may be mediated by the functional fitness index.

Methods

All participants (n = 123) performed the following tests: indirect maximal oxygen uptake (VO₂max), AAHPERD Functional Fitness Battery Test to determine the general fitness functional index (GFFI), systolic and diastolic blood pressure (SBP and DBP), body mass index (BMI) and blood sample collection to evaluate the total-cholesterol (CHOL), LDL-cholesterol (LDL-c), HDL-cholesterol (HDL-c), triglycerides (TG), uric acid (UA), nitrite (NO2) and thiobarbituric acid reactive substances (T-BARS). After the physical, hemodynamic and metabolic evaluations, all participants were allocated into three groups according to their GFFI: G1 (regular), G2 (good) and G3 (very good).

Results

Baseline blood pressure was higher in G1 when compared to G3 (+12% and +11%, for SBP and DBP, respectively, p<0.05) and the subjects who had higher values of BP also presented higher values of UA. Although UA was not different among GFFI groups, it presented a significant correlation with GFFI and VO₂max. Also, nitrite concentration was elevated in G3 compared to G1 (140±29 μM vs 111± 29 μM, for G3 and G1, respectively, p<0.0001). As far as the lipid profile, participants in G3 presented better values of CHOL and TG when compared to those in G1.

Conclusions

Taking together the findings that subjects with higher BP had elevated values of UA and lower values of nitrite, it can be suggested that the relationship between blood pressure and the oxidative stress produced by acid uric may be mediated by training status.

Age and association of kidney measures with mortality and end-stage renal disease

CONTEXT

Chronic kidney disease (CKD) is prevalent in older individuals, but the risk implications of low estimated glomerular filtration rate (eGFR) and high albuminuria across the full age range are controversial.

OBJECTIVE

To evaluate possible effect modification (interaction) by age of the association of eGFR and albuminuria with clinical risk, examining both relative and absolute risks.

DESIGN, SETTING, AND PARTICIPANTS

Individual-level meta-analysis including 2,051,244 participants from 33 general population or high-risk (of vascular disease) cohorts and 13 CKD cohorts from Asia, Australasia, Europe, and North/South America, conducted in 1972-2011 with a mean follow-up time of 5.8 years (range, 0-31 years).

MAIN OUTCOME MEASURES

Hazard ratios (HRs) of mortality and end-stage renal disease (ESRD) according to eGFR and albuminuria were meta-analyzed across age categories after adjusting for sex, race, cardiovascular disease, diabetes, systolic blood pressure, cholesterol, body mass index, and smoking. Absolute risks were estimated using HRs and average incidence rates.

RESULTS

Mortality (112,325 deaths) and ESRD (8411 events) risks were higher at lower eGFR and higher albuminuria in every age category. In general and high-risk cohorts, relative mortality risk for reduced eGFR decreased with increasing age; eg, adjusted HRs at an eGFR of 45 mL/min/1.73 m2 vs 80 mL/min/1.73 m2 were 3.50 (95% CI, 2.55-4.81), 2.21 (95% CI, 2.02-2.41), 1.59 (95% CI, 1.42-1.77), and 1.35 (95% CI, 1.23-1.48) in age categories 18-54, 55-64, 65-74, and ≥75 years, respectively (P <.05 for age interaction). Absolute risk differences for the same comparisons were higher at older age (9.0 [95% CI, 6.0-12.8], 12.2 [95% CI, 10.3-14.3], 13.3 [95% CI, 9.0-18.6], and 27.2 [95% CI, 13.5-45.5] excess deaths per 1000 person-years, respectively). For increased albuminuria, reduction of relative risk with increasing age was less evident, while differences in absolute risk were higher in older age categories (7.5 [95% CI, 4.3-11.9], 12.2 [95% CI, 7.9-17.6], 22.7 [95% CI, 15.3-31.6], and 34.3 [95% CI, 19.5-52.4] excess deaths per 1000 person-years, respectively by age category, at an albumin-creatinine ratio of 300 mg/g vs 10 mg/g). In CKD cohorts, adjusted relative hazards of mortality did not decrease with age. In all cohorts, ESRD relative risks and absolute risk differences at lower eGFR or higher albuminuria were comparable across age categories.

CONCLUSIONS

Both low eGFR and high albuminuria were independently associated with mortality and ESRD regardless of age across a wide range of populations. Mortality showed lower relative risk but higher absolute risk differences at older age.

Comparison of risk prediction using the CKD-EPI equation and the MDRD study equation for estimated glomerular filtration rate

CONTEXT

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation more accurately estimates glomerular filtration rate (GFR) than the Modification of Diet in Renal Disease (MDRD) Study equation using the same variables, especially at higher GFR, but definitive evidence of its risk implications in diverse settings is lacking.

OBJECTIVE

To evaluate risk implications of estimated GFR using the CKD-EPI equation compared with the MDRD Study equation in populations with a broad range of demographic and clinical characteristics.

DESIGN, SETTING, AND PARTICIPANTS

A meta-analysis of data from 1.1 million adults (aged ≥ 18 years) from 25 general population cohorts, 7 high-risk cohorts (of vascular disease), and 13 CKD cohorts. Data transfer and analyses were conducted between March 2011 and March 2012.

MAIN OUTCOME MEASURES

All-cause mortality (84,482 deaths from 40 cohorts), cardiovascular mortality (22,176 events from 28 cohorts), and end-stage renal disease (ESRD) (7644 events from 21 cohorts) during 9.4 million person-years of follow-up; the median of mean follow-up time across cohorts was 7.4 years (interquartile range, 4.2-10.5 years).

RESULTS

Estimated GFR was classified into 6 categories (≥90, 60-89, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m(2)) by both equations. Compared with the MDRD Study equation, 24.4% and 0.6% of participants from general population cohorts were reclassified to a higher and lower estimated GFR category, respectively, by the CKD-EPI equation, and the prevalence of CKD stages 3 to 5 (estimated GFR <60 mL/min/1.73 m(2)) was reduced from 8.7% to 6.3%. In estimated GFR of 45 to 59 mL/min/1.73 m(2) by the MDRD Study equation, 34.7% of participants were reclassified to estimated GFR of 60 to 89 mL/min/1.73 m(2) by the CKD-EPI equation and had lower incidence rates (per 1000 person-years) for the outcomes of interest (9.9 vs 34.5 for all-cause mortality, 2.7 vs 13.0 for cardiovascular mortality, and 0.5 vs 0.8 for ESRD) compared with those not reclassified. The corresponding adjusted hazard ratios were 0.80 (95% CI, 0.74-0.86) for all-cause mortality, 0.73 (95% CI, 0.65-0.82) for cardiovascular mortality, and 0.49 (95% CI, 0.27-0.88) for ESRD. Similar findings were observed in other estimated GFR categories by the MDRD Study equation. Net reclassification improvement based on estimated GFR categories was significantly positive for all outcomes (range, 0.06-0.13; all P < .001). Net reclassification improvement was similarly positive in most subgroups defined by age (<65 years and ≥65 years), sex, race/ethnicity (white, Asian, and black), and presence or absence of diabetes and hypertension. The results in the high-risk and CKD cohorts were largely consistent with the general population cohorts.

CONCLUSION

The CKD-EPI equation classified fewer individuals as having CKD and more accurately categorized the risk for mortality and ESRD than did the MDRD Study equation across a broad range of populations.

Association among serum uric acid, cardiovascular risk, and arterial stiffness: a cross-sectional study in She ethnic minority group of Fujian Province in China

OBJECTIVES

To investigate the association between serum uric acid levels, cardiovascular risk, and arterial stiffness in She ethnic minority in South China's Fujian Province.

METHODS

5109 participants aged 20-79 yr were enrolled in analysis. Tpeak-Tend interval (Tp-e), QT interval, and height of the R wave in lead aVL (aVLR) were measured on 12-lead electrocardiogram (ECG), and Minnesota code-indicated major abnormal ECG MA-ECG was used as a risk indicator of cardiovascular disease. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV).

RESULTS

Longer Tp-e interval, greater Tp-e/QT ratio, and higher aVLR were observed in the highest quartile of uric acid level. The incidence of MA-ECG was gradually increased from lowest to highest quartile of serum uric acid in males (p for trend <0.01). After adjusting traditional cardiovascular risk factors, multivariate analysis revealed that the fourth quartile of serum uric acid level was independently associated with MA-ECG in males [odds ratios (OR) (95% confidence interval): 2.129 (1.376-3.295)] but not in females. Serum uric acid was also associated with abnormal baPWV, when adjusted for atherogenic confounders. Compared with the lowest serum uric acid quartile, the OR (95% confidence interval) of the second, third, and fourth quartile were 1.920 (1.246-2.957), 1.650 (1.064-2.558), and 2.501 (1.600-3.908) in males.

CONCLUSION

Among China's She ethnic minority, uric acid level was independently related to arterial stiffness assessed by baPWV in both genders. The evaluation of uric acid level was related to higher cardiovascular risk in males but not in females.

Hyperuricemia and the echocardiographic measures of myocardial dysfunction

Few studies have investigated the association between hyperuricemia and subclinical myocardial dysfunction. The authors analyzed the relationship between serum uric acid and subclinical markers of heart failure in participants in the Framingham Offspring Cohort (N=2169, mean age 57.3 years, 55.4% women). Cardiac dysfunction was assessed through echocardiographic measurements of left ventricular (LV) mass and thickness, end-diastolic LV thickness, and LV fractional shortening at the sixth visit, approximately 24 years after study onset. Participants in the highest serum uric acid quartile (≥ 6.2 mg/dL serum uric acid) had a significantly greater frequency of echocardiographic abnormalities compared with those in the lowest quartile (<4.3 mg/dL). Those in the highest quartile had multivariable-adjusted odds ratios of 9.013 (95% confidence interval, 2.051-39.604) for abnormal LV ejection fraction and 4.584 (95% confidence interval, 1.951-10.768) for LV systolic dysfunction compared with those in the lowest quartile. Hyperuricemia in young adults can be a marker for subsequent heart failure.

New and improved strategies for the treatment of gout

The Western world appears to be in the midst of the third great gout epidemic of all time. In this century, gout is increasing in prevalence despite an increased understanding of its risk factors and pathophysiology, and the availability of reasonably effective treatment. The main cultural factors responsible for this appear to be diet, obesity, ethanol use and medications. Excess fructose consumption is a newly recognized modifiable risk factor. The debate has been renewed concerning hyperuricemia as an independent risk factor for renal insufficiency and cardiovascular disease. Prevention is still rooted in lifestyle choices. Existing treatments have proven to be unsatisfactory in many patients with comorbidities. New treatments are available today and on the horizon for tomorrow, which offer a better quality of life for gout sufferers. These include febuxostat, a nonpurine inhibitor of xanthine oxidase with a potentially better combination of efficacy and safety than allopurinol, and investigational inhibitors of URAT-1, an anion exchanger in the proximal tubule that is critical for uric acid homeostasis. New abortive treatments include interleukin-1 antagonists that can cut short the acute attack in 1 to 2 days in persons who cannot take nonsteroidal anti-inflammatory drugs, colchicine or corticosteroids. Lastly, newer formulations of uricase have the ability to dissolve destructive tophi over weeks or months in patients who cannot use currently available hypouricemic agents. Diagnostically, ultrasound and magnetic resonance imaging offer advanced ways to diagnose gout noninvasively, and just as importantly, a way to follow the progress of tophus dissolution. The close association of hyperuricemia with metabolic syndrome, hypertension and renal insufficiency ensures that nephrologists will see increasing numbers of gout-afflicted patients.

Association between serum uric acid levels and cardiometabolic risk factors among Japanese junior high school students

BACKGROUND

The present study was designed to examine whether serum uric acid (SUA) levels were associated with cardiometabolic risk factors and to determine optimal cut-offs for SUA to identify multiple risk factors among Japanese junior high school students.

METHODS AND RESULTS

A total of 958 students (518 boys and 440 girls, aged 12.1-15.0 years) who were enrolled between April 2005 and June 2008 were divided into 4 groups according to SUA quartiles. Compared with the lowest quartile of SUA, prevalence of abdominal obesity, hypertension, and dyslipidemia was significantly increased in the highest quartile in boys and that of abdominal obesity was increased in the highest quartile in girls. The adjusted odds ratios (95% confidence interval) of the highest quartile of SUA for 2 or more cardiometabolic risk factors were 2.59 (1.16-5.79) for boys and 1.54 (0.43-5.56) for girls. Receiver operating characteristic curve analysis demonstrated that the most appropriate cut-offs for SUA to identify multiple cardiometabolic risk factors were 6.4 mg/dl for boys and 4.9 mg/dl for girls.

CONCLUSIONS

SUA was strongly associated with the prevalence of cardiometabolic risk factors among male Japanese junior high school students. The present study may provide insights into the role of SUA in the school screening system for the development of educational programs on prevention of lifestyle-related diseases among school children.

Hyperuricemia and its association with carotid intima-media thickness in hypertensive and non hypertensive patients

Carotid intima-media thickness (C-IMT) measured noninvasively by ultrasonography is widely used as a marker for increased risk of cardiovascular disease. Also hyperuricemia (HU) is a well recognized risk factor for cardiovascular diseases. The study was designed to assess the relation between hyperuricemia and carotid intima-media thickness C-IMT in patients with and without hypertension (HTN). This study included 126 patients divided into four groups: (1) Group A, included 59 hypertensive patients with hyperuricemia. (2) Group B, included 29 hypertensive patients without hyperuricemia. (3) Group C, included 17 patients with hyperuricemia and normal blood pressure without history of hypertension. (4) Group D, included 21 control subjects. We measured carotid intima-media thickness by B-mode ultrasound in the common carotid and internal carotid artery. Routine echocardiography and uric acid level was assessed for all patients. We found that C-IMT was significantly higher in group A, B and C than group D; and it was significantly higher in group A than B. This means that C-IMT is significantly higher in all hypertensive groups than control group but it was significantly higher in hypertensive hyperuricemia (group A) than those hypertensives without hyperuricemia. We also observed a higher C-IMT in hyperuricemic non hypertensive patients than control group this means that hyperuricemia per se could be a risk factor for atherosclerosis. Uric acid levels among the whole number of patients included in the study and among the groups with hyperuricemia (group A and C) were positively correlated with the intimal-media thickness (IMT) while there were no correlations in the other two groups without hyperuricemia. We found that left ventricular hypertrophy (LVH) was significantly higher in hypertensive patients (group A&B) than normotensives (group C&D) either with or without hyperuricemia and this was evident in the hypertensive hyperuricemic patients (group A); but unexpectedly we observed the presence of LVH in the hyperuricemic non hypertensive patients (group C) which was significantly higher than the control group (group D). This means that hyperuricemia is a risk factor for development of LVH hypertrophy independently of hypertension. Therefore, higher serum uric acid levels are associated with increased C-IMT and left ventricular hypertrophy in hypertensive and even non hypertensive patients. So, early screening for hyperuricemia and lowering serum uric acid levels might be beneficial in slowing progression of atherogenesis.