Serum urate and the risk of major coronary heart disease events

Serum uric acid: an independent risk factor for cardiovascular disease in Pakistani Punjabi patients

BACKGROUND

It is well-known that serum uric acid (SUA) can increase the risk of hypertension, diabetes, obesity and dyslipidemia. However, its independent association with the risk of cardiovascular diseases (CVD) is controversial particularly in different populations. Hence, this study was aimed to assess an independent association of SUA with CVD risk in a Punjabi Pakistani cohort.

METHODS

This is a retrospective observational study in which 502 human subjects having CVD, hypertension and/or diabetes were grouped based on SUA levels as normouricemia (n = 266) and hyperuricemia (n = 236). Role of SUA was assessed in increasing the risk of CVD independent of other key confounding factors (i.e. age, gender, dyslipidemia, hypertension, diabetes, dietary and life-style habits). All clinical and biochemical data were analyzed in SPSS (ver. 20).

RESULTS

Subjects aged 55 ± 13 years were of both genders (males: 52%). SUA levels were significantly different among clinical subtypes of CVD [i.e. acute coronary syndrome (ACS), myocardial infarction (MI) and heart failure (HF)]. Spearman correlation showed a significantly positive association between CVD and SUA (rho = 0.149, p < 0.001). Multivariate logistic regression of SUA quartiles showed that hyperuricemia is associated with CVD [3rd quartile: OR: 1.78 (CI: 1.28-2.48), p = 0.001 and 4th quartile: OR: 2.37 (CI: 1.72-3.27), p < 0.001]. Moreover, this association remained significant even after adjusting for confounding factors.

CONCLUSION

This study showed that SUA is positively associated with CVD, thus it can act as an independent risk factor for CVD.

A Study of Lipid Profile and the Correlation of Serum Uric Acid Levels in Patients With Hypertension

Aim We examine the lipid profile and correlation of serum uric acid (SUA) levels in cases of hypertension and normotensives. Methods The current observational study spanned between April 2022 and April 2024. Throughout the research, 200 patients were examined; 100 of these patients were classified as Stage 1 or Stage 2 hypertensive (as per the seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure), while the other 100 served as controls, meaning they did not have hypertension or any other medical condition that could lead to elevated SUA levels. Results It was revealed that the proportion of hypertension was higher in males compared to females. Of the total male patients, most (41.1%) patients had grade 1 hypertension and grade 2 hypertension, while among females, 20% had grade 1 hypertension. It was seen that as age increases, systolic blood pressure (SBP) and diastolic blood pressure (DBP) also rise among the two study groups, although the correlation was not statistically significant between blood pressure level and age of study subjects. The hypertensive patients have increased SBP and DBP levels when compared to the control group, which is significant. The lipid profile shows that the hypertensive subjects had significantly higher mean low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and triglyceride levels than controls. SUA levels were observed to be elevated in the hypertensive subjects implying a positive correlation between the level of uric acid and blood pressures. Conclusion We found evidence that hyperuricemia and hypertension go hand in hand. A statistically noteworthy positive connection was found between the systolic blood pressures and lipid profiles of the patients. Hypertensive patients were found to have hyperlipidemia, whereas normotensive controls had normal lipid profiles. Moreover, it was seen that there was a positive correlation between SBP and chronological age in hypertensive cases, although this was statistically not significant.

A Ten-Year Follow-Up Study of the Association Between Uric Acid and Adverse Cardiovascular Events in Patients With Coronary Artery Disease

The association between uric acid (UA) and long-term mortality in patients with coronary artery disease is poorly investigated. We assessed the association between UA and 10-year mortality after percutaneous coronary intervention (PCI) in 3,998 patients who underwent PCI. Patients were categorized in groups according to UA tertiles: tertile 1 (UA <5.80 mg/100 ml, n = 1,347), tertile 2 (UA 5.80 to 7.04 mg/100 ml, n = 1,340), and tertile 3 (UA >7.94 mg/100 ml, n = 1,311). The primary outcome was 10-year all-cause mortality. All-cause deaths occurred in 1,200 patients: 320 deaths (26.5%) in patients with UA in the first tertile, 325 deaths (26.9%) in patients with UA in the second tertile, and 555 deaths (46.0%) in patients with UA in the third tertile (adjusted hazard ratio 1.22, 95% confidence interval 1.17 to 1.27, p <0.001) for 1 mg/100 ml increment in UA level. Cardiac deaths occurred in 748 patients: 194 deaths (16.5%) in patients with UA in the first tertile, 202 deaths (17.0%) in patients with UA in the second tertile, and 352 deaths (29.7%) in patients with UA in the third tertile (adjusted hazard ratio 1.24 [1.17 to 1.32], p <0.001) for 1 mg/100 ml increment in the UA level. The 10-year rates of target lesion revascularization, target vessel revascularization, or nontarget vessel revascularization did not differ significantly according to the UA level. In conclusion, in patients with coronary artery disease treated with PCI, increased UA level was associated with higher 10-year mortality. Increased UA level was not associated with the progression of atherosclerosis in nontreated coronary vessels or progression of intimal hyperplasia in stented lesions requiring intervention.

Uric Acid Levels, Number of Standard Modifiable Cardiovascular Risk Factors, and Prognosis in Patients With Coronary Artery Disease: A Large Cohort Study in Asia

Background Serum uric acid (UA) is correlated closely with traditional cardiovascular risk factors, which might interfere with the action of UA, in patients with coronary artery disease. We performed this study to evaluate the prognostic effect of UA levels in individuals with different numbers of standard modifiable cardiovascular risk factors (SMuRFs). Methods and Results In this prospective study, we consecutively enrolled 10 486 patients with coronary artery disease. They were stratified into 3 groups according to the tertiles of UA concentrations and, within each UA tertile, further classified into 3 groups by the number of SMuRFs (0-1 versus 2-3 versus 4). The primary end point was major adverse cardiovascular and cerebrovascular events (MACCEs), including death, myocardial infarction, stroke, and unplanned revascularization. Over a median follow-up of 2.4 years, 1233 (11.8%) MACCEs were recorded. Patients with high UA levels developed significantly higher risk of MACCEs than those with low UA levels. In addition, UA levels were positively associated with MACCEs as a continuous variable. More importantly, in patients with 0 to 1 SMuRF, the risks of MACCEs were significantly higher in the high-UA-level group (adjusted hazard ratio [HR], 1.469 [95% CI, 1.197-1.804]) and medium-UA-level group (adjusted HR, 1.478 [95% CI, 1.012-2.160]), compared with the low-UA-level group, whereas no significant association was found between UA levels and the risk of MACCEs in participants with 2 to 3 or 4 SMuRFs. Conclusions In patients with coronary artery disease who received evidence-based secondary prevention therapies, elevated UA levels might affect the prognosis of individuals with 0 to 1 SMuRF but not that of individuals with ≥2 SMuRFs.

Uric Acid and Risk of Cardiovascular Disease and Mortality: A Longitudinal Cohort Study

BACKGROUND

This study aimed to examine the association of serum uric acid levels with incident cardiovascular disease and mortality in Korean adults without gout.

METHODS

This large longitudinal cohort study included adults aged > 19 years who had serum uric acid levels measured at least once at the National Health Insurance Service Ilsan Hospital from January 1, 2006 to December 31, 2015. Longitudinal data on person-level cardiovascular disease and cardiovascular mortality were linked to the National Health Insurance Service claims database and National Death Index.

RESULTS

Among a total of 92,454 study participants with a median follow-up of 4.7 years, 7,670 (8.3%) composite events of cardiovascular disease or cardiovascular mortality were observed. Multivariable Cox proportional-hazards models revealed that each 1 mg/dL increment in uric acid level was associated with a 6% higher risk of composite outcomes. Compared with that for the uric acid level category of 4.0 to < 5.0 mg/dL, adjusted hazard ratios (95% confidence interval) for uric acid level categories of 5.0 to < 6.0, 6.0 to < 7.0, and ≥ 7.0 mg/dL were 1.10 (1.04-1.18), 1.20 (1.11-1.30), and 1.36 (1.25-1.47), respectively. In the secondary analyses for cardiovascular disease or cardiovascular mortality examined separately, a higher uric acid level was similarly associated with a higher risk of each adverse outcome. These associations were generally consistent across clinically relevant subgroups.

CONCLUSION

A graded association was noted between serum uric acid levels and cardiovascular risk, suggesting that higher uric acid levels may adversely affect cardiovascular health and survival in individuals without gout.

Change of serum uric acid and progression of cardiometabolic multimorbidity among middle aged and older adults: A prospective cohort study

Background

Hyperuricemia is prevalent and associated with individual cardiometabolic diseases, highlighting the potential role of serum uric acid (SUA) in the development and progression of cardiometabolic multimorbidity (CMM, the coexistence of diabetes, heart disease, or stroke). This study aimed to examine the role of SUA change in the progression of CMM.

Methods

This prospective cohort study used data from the China Health and Retirement Longitudinal Study, included 4,820 participants aged 45 years or above with three complete surveys at 2011 (baseline), 2015, and 2018. SUA level at survey 2011 and 2015 was used to measure SUA change as keeping or rising to hyperuricemia, and keeping or declining to non-hyperuricemia. CMM progression was defined as the first report of CMM or additional report of cardiometabolic diseases during survey 2015 and 2018. We used logistic regression models to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) of SUA change on CMM progression.

Results

During the follow-up of around 7 years, 519 (10.8%) of the participants kept or rose to hyperuricemia from survey 2011 to 2015, and 311 (6.5%) experienced CMM progression from survey 2015 to 2018. Participants who kept or rose to hyperuricemia had 1.86 (95% CI, 1.29, 2.68) increased odds of CMM progression compared with those who kept or declined to non-hyperuricemia. Specifically, keeping or rising to hyperuricemia (vs. keeping or declining to non-hyperuricemia) was associated with 2.01 times higher odds (95% CI, 1.18, 3.43) of incident diabetes and 1.67 times higher odds (OR:1.67; 95% CI, 1.15, 2.43) of incident cardiovascular diseases following diabetes.

Conclusion

Keeping or rising to hyperuricemia was associated with CMM progression, particularly with incident cardiovascular diseases following diabetes. These findings suggest that monitoring SUA change may provide innovative insights into the prevention of CMM, especially in the secondary prevention of CMM (i.e., preventing further progression to cardiovascular diseases among patients with diabetes).

Effect and correlation of patent vascular access flow on left ventricular hypertrophy in kidney transplant patients

Background

Patency of vascular accesses (VA) is associated with left ventricular hypertrophy (LVH) in kidney transplant recipients (KTR). This level of VA flow (VAF) as related to LVH was assessed and an upward level of VA flow recommended for VA closure determined. This recommendation has not been previously reported.

Methods

123 KTR cohort patients were enrolled between August 2016 and December 2017 and their LVH and LV mass index (LVMI) by echocardiography and VAF by Doppler ultrasound were evaluated at baseline and for a 24-month follow-up period. Associations between VAF and LVH were adjusted for other factors.

Results

Patients with patent VA (55.3%) had significantly greater LVH (47.1 vs. 29.1%, an adjusted odds ratio 2.44, p = 0.03) and LVMI (112.15 ± 34.4 vs. 97.55 ± 23.55 g/m², p = 0.009) when compared with the non-VA group. A positive correlation between VAF rate and LVM was noted (r = 0.40, p < 0.001). Subgroup analysis revealed the VAF ≥ 900 ml/min had risks of LVH 3.61, and 2.86 times compared with the non-VA group and the VAF < 900 ml/min group. After a 24-month follow up, there was no significantly individual change in LVMI in patients with or without VA except 6 patients who lost their VA patency during follow-up time had a significant reduction of LVMI (120.17 ± 52.13 to 80.89 ± 22.72 g/m², p = 0.046).

Conclusions

Patency of VA in post-KT patients was associated with LVH. There was a significant reduction of LMVI after loss of VA patency. Patients with stable kidney graft function should be considered for VA closure especially if VAF is ≥ 900 ml/min.

Association between gout and cardiovascular outcomes in adults with no history of cardiovascular disease: large data linkage study in New Zealand

Objective

To examine the association of gout with cardiovascular outcomes using linked administrative health data in Aotearoa New Zealand.

Design

Data linkage study.

Setting

National registries of pharmaceutical dispensing, hospital admission, and deaths linked to the Auckland/Northland regional repository of laboratory results to create a regional health contact population as of 31 December 2011.

Participants

942 416 residents of the Auckland/Northland region, aged 20-79 years with no history of cardiovascular disease.

Main outcome measures

Time to first fatal or non-fatal cardiovascular event, identified from national datasets on hospital admissions and mortality, between 1 January 2012 and 31 December 2016. Cardiovascular disease was broadly defined as comprising ischaemic heart disease, ischaemic or haemorrhagic stroke, transient ischaemic attack, peripheral vascular disease, and heart failure.

Interventions

A history of gout identified from a discharge diagnosis of gout from a public hospital admission or previous dispensing of gout specific drug treatments. The cohort was then linked to national hospital admissions and deaths through to 31 December 2016 (ie, 5 years' follow-up). Multivariable Cox proportional hazard models were constructed to assess the associations between gout, other risk factors, and cardiovascular outcomes.

Results

Of 942 416 people included in the study, 31 907 (3.4%) had gout (6261 women and 25 646 men). After adjustment for multiple risk factors for cardiovascular disease, gout was associated with increased cardiovascular events (adjusted hazard ratio 1.34 (95% confidence interval 1.23 to 1.45) in women; 1.18 (1.12 to 1.24) in men). For men with gout, there was an increased risk of cardiovascular disease in those who were not dispensed regular allopurinol (1.15 (1.05 to 1.25)) and those with a serum urate above the treatment target of 0.36 mmol/L (1.16 (1.04 to 1.30)). Risk of cardiovascular events was lower for men with gout who were not dispensed colchicine compared with those who were (0.84 (0.77 to 0.92)). These findings were not observed in women.

Conclusion

These results indicate that gout is associated with an increased risk of cardiovascular events. In men with gout without history of cardiovascular disease, the cardiovascular risk was lower in those regularly dispensed allopurinol and those with serum urate levels at the recommended treatment target. By contrast, colchicine dispensing was associated with an increased risk of cardiovascular events in men with gout without a cardiovascular history. The potential causal mechanisms of these associations require further exploration, including casual inference modelling in future studies.

High-level uric acid in asymptomatic hyperuricemia could be an isolated risk factor of cardio-cerebrovascular diseases: A prospective cohort study

BACKGROUND AND AIMS

Whether the asymptomatic hyperuricemia (AH) raise the cardiovascular disease risk with or without hyperuricemia-related comorbidities still remains contentious. Our study was aimed to quantitatively access the incidence risk of coronary heart disease (CHD) and stroke associated with AH.

METHODS AND RESULTS

In this prospective cohort study, multivariate-adjusted Cox regression models were applied to evaluate the risk of cardiovascular disease (CVD). Baseline serum uric acid beyond normouricemia (357 mmol/L) was quarterly stratified based on the distribution of healthy populations without CVD onset. 1062 CVD first-attack cases were collected among the 29,974 study population (age range: 18-91, mean age: 47.2 ± 13.9 years-old) with a mean follow-up duration of 5.78 ± 0.83 years. The AH showed overall non-association with the CVD incident. However, significantly increased adjusted hazard ratio (HR) of CVD with 95% confidence interval (CI) were observed when the fourth quartile compared with normouricemia stratum in the total cohort population (CHD: 1.42, 1.21-1.68; stroke: 1.27, 1.06-1.41), male (CHD: 1.26, 1.12-1.55), female (CHD: 1.34, 1.04-2.02; stroke: 2.06, 1.13-3.77) and aged over 50 years-old population. Meanwhile, the age-standardized incidence rate of CVD in the fourth quartile was 2-3 times higher than the normouricemia population. After excluded 14,464 baseline population with diabetes, dyslipidemia, and hypertension, consistent results were also observed in the AH population in absence of comorbidities (CHD: 1.51, 1.22-2.25; stroke: 1.68, 1.13-2.39).

CONCLUSION

Asymptomatic hyperuricemia patients exposed to a higher level of uric acid (>=428 mmol/L) could significantly increase the incidence risk of CHD and stroke, with or without hyperuricemia-related comorbidities.

Association of hyperuricemia and serum uric acid lowering therapy with mortality in hemodialysis patients

Introduction

In the general population, hyperuricemia is associated with increased morbidity and mortality. Data on this association in hemodialysis patients is controversial. Moreover, it remains elusive whether serum uric acid (SUA) lowering therapy is associated with mortality.

Methods

Retrospective analysis of 601 patients on chronic hemodialysis therapy in five outpatient centers with a maximum follow-up of 100 and a mean follow-up of 41 months. Death was defined as primary endpoint. Cumulative survival was analyzed by Kaplan–Meier analysis and Cox regressions adjusted for age.

Findings

Cumulative survival rates were higher for those subjects with a higher than median SUA concentration both based on mean annual and baseline measurements (p < 0.05 each). There was no survival difference anymore after adjustment for age (p > 0.05 each). Stratification for SUA lowering therapy (allopurinol/febuxostat) had no impact on cumulative survival, neither in Kaplan Meier nor in Cox regression analyses (p > 0.05 each). Furthermore, Cox regression analysis excluded an increased cardiovascular mortality in subjects with hyperuricemia.

Discussion

In contrast to the general population, hyperuricemia is not associated with increased mortality in patients undergoing hemodialysis. Moreover, xanthine oxidase inhibition was not associated with a survival benefit in this analysis. These data do not support the use of SUA lowering medication in hemodialysis patients with asymptomatic hyperuricemia.

Cumulative Serum Uric Acid and Its Time Course Are Associated With Risk of Myocardial Infarction and All-Cause Mortality

Background Serum uric acid (SUA) has been demonstrated as a risk factor for myocardial infarction (MI) and all-cause mortality; however, the impact of cumulative SUA (cumSUA) remains unclear. We aimed to investigate the association of cumSUA with MI risk and all-cause mortality, and to further explore the effects of SUA accumulation time course. Methods and Results The study enrolled 53 463 participants without a history of MI, and these participants underwent 3 examinations during 2006 to 2010. cumSUA from baseline to the third examination was calculated, multiplying mean values between consecutive examinations by time intervals between visits. Cox models estimated hazard ratios (HRs) and 95% CIs of MI and all-cause mortality for cumSUA quartiles, hyperuricemia exposure duration, and SUA accumulation time course. During a median follow-up of 7.04 years, 476 incident MIs and 2692 deaths occurred. In the fully adjusted model, a higher MI risk was observed in the highest cumSUA quartile (HR, 1.48; 95% CI, 1.10-1.99), in participants with longer hyperuricemia exposure duration (HR, 1.71; 95% CI, 1.06-2.73), and in participants with cumSUA≥median and a negative slope (HR, 1.58; 95% CI, 1.18-2.11). Similar associations persisted for all-cause mortality. Conclusions The risk of MI and all-cause mortality increased with higher cumSUA and was affected by the SUA accumulation time course. Early SUA accumulation contributed more to MI risk and all-cause mortality than later SUA accumulation with the same overall cumulative exposure, emphasizing the importance of optimal SUA control early in life.

Early onset of hyperuricemia is associated with increased cardiovascular disease and mortality risk

BACKGROUND

Hyperuricemia is associated with cardiovascular mortality, but the association of the age at hyperuricemia onset with cardiovascular disease (CVD) and mortality is still unclear.

OBJECTIVE

The purpose of this study was to examine the associations of hyperuricemia onset age with CVD and all-cause mortality.

METHODS

A total of 82,219 participants free of hyperuricemia and CVD from 2006 to 2015 in the Kailuan study were included. The analysis cohort comprised 18,311 new-onset hyperuricemia patients and controls matched for age and sex from the general population. Adjusted associations were estimated using Cox models for CVD and all-cause mortality across a range of ages.

RESULTS

There were 1,021 incident cases of CVD (including 215 myocardial infarctions, 814 strokes) and 1459 deaths during an average of 5.2 years of follow-up. Patients with hyperuricemia onset at an age < 45 years had the highest hazard ratios (HRs) (1.78 (1.14-2.78) for CVD and 1.64 (1.04-2.61) for all-cause mortality relative to controls). The HRs of CVD and all-cause mortality were 1.32 (1.05-1.65) and 1.40 (1.08-1.81) for the 45-54 years age group, 1.23 (0.97-1.56) and 1.37 (1.11 to 1.72) for the 55-64 years age group, and 1.10 (0.88-1.39) and 0.88 (0.76-1.01) for the ≥ 65 years age group, respectively.

CONCLUSIONS

The age at hyperuricemia onset was identified as an important predictor of CVD and all-cause mortality risk, and the prediction was more powerful in those with a younger age of hyperuricemia onset. Early onset of hyperuricemia is associated with increased cardiovascular disease and mortality risk.

Trends of venous thromboembolism risk before and after diagnosis of gout: a general population-based study

OBJECTIVE

To estimate the overall risk and the temporal trend of venous thromboembolism (VTE), deep vein thrombosis (DVT), and pulmonary embolism (PE) before and after gout diagnosis in an incident gout cohort compared with the general population.

METHODS

We conducted a matched cohort study using a province-wide population-based administrative health database in Canada. We calculated incidence rates (IRs) and multivariable adjusted hazard ratios (HRs) for the risk of VTE, DVT and PE before and after gout diagnosis.

RESULTS

Among 130 708 incident individuals with gout (64% male, mean age 59 years), 2071 developed VTE, 1377 developed DVT and 1012 developed PE. IRs per 1000 person-years for gout were 2.63, 1.74 and 1.28 compared with 2.03, 1.28 and 1.06 for non-gout, respectively. The fully adjusted HRs (95% CI) for VTE, DVT and PE were 1.22 (1.13, 1.32), 1.28 (1.17, 1.41) and 1.16 (1.05, 1.29). For the pre-gout period, the fully adjusted HRs (95% CI) were 1.51 (1.38, 1.64), 1.55 (1.40, 1.72) and 1.47 (1.31, 1.66) for VTE, DVT and PE. During the third, second and first years preceding gout, the fully adjusted HRs for VTE were 1.44, 1.56 and 1.62. During the first, second, third, fourth and fifth years after gout, the fully adjusted HRs were 1.63, 1.29, 1.33, 1.28 and 1.22. Similar trends were also seen for DVT and PE.

CONCLUSION

Increased risks of VTE, DVT and PE were found both before and after gout diagnosis. The risk increased gradually before gout, peaking in the year prior to diagnosis, and then progressively declined. Gout-associated inflammation may contribute to venous thrombosis risk.

The differential role of uric acid - The purpose or cause of cardiovascular diseases?

For 40 years many studies have been conducted to verify the connection between serum uric acid concentration and cardiovascular diseases, such as myocardial infarction. Unfortunately, it remains unclear which form of uric acid - prooxidant or antioxidant - could be a predictive marker of cardiovascular disease, especially in patients after myocardial infarction. It is well-known that uric acid is an organic compound and the water-soluble final product of purine catabolism, which is catalysed by xanthine oxidoreductase and excreted by kidneys. An increased concentration of UA in human plasma leads to diseases like tumours, renal disorders, atherosclerosis, hypertension, diabetes, metabolic syndrome, polycythaemia vera, haemolytic anaemias, ischemia, oxidative stress, and rare genetic disorders connected with UA degradation. Epidemiological studies have shown that UA might be a marker of oxidative stress, progression of inflammation, or renal disease. A fortiori, it is possible that could also be a predictor for short/long-term survival of patients with CVD. Evidence provided by multiple studies is controversial and mutually exclusive. Among 71 studies the most of them found an independent association between SUA and CVD risk. Some of those studies confirm that CVD risk is higher in women who had elevated SUA levels. On the other hand, many studies reached the opposite conclusion and did not find any relationship between SUA and CVD mortality and morbidity.

Hyperuricemia is a Risk Factor for One-Year Overall Survival in Elderly Female Patients with Acute Coronary Syndrome

Background

Hyperuricemia is a risk factor for cardiovascular diseases, but the impact of hyperuricemia and sex-related disparities is not fully clear in elderly patients with acute coronary syndrome (ACS).

Objective

To investigate the association between hyperuricemia and 1-year all-cause mortality in elderly patients with ACS.

Methods

This retrospective cohort study included 711 consecutive ACS patients aged ≥75 years, hospitalized in our center between January 2013 and December 2017. Serum uric acid (sUA), in-hospital events, and 1-year follow-up were analyzed. Multivariable logistic regression models were used to explore the risk factors for in-hospital events and 1-year all-cause mortality.

Results

sUA levels were higher in males than in females (381.4 ± 110.1 vs. 349.3 ± 119.1 μmol/l, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%,

Conclusions

Hyperuricemia is an independent risk factor for 1-year all-cause mortality in elderly female patients with ACS.

Obesity-Related Genetic Variants and Hyperuricemia Risk in Chinese Men

Objective: Obesity/metabolic syndrome and hyperuricemia are clinically associated; however, the association of obesity/metabolic syndrome-related genetic variants with hyperuricemia is not clear. Therefore, we assessed this association in Chinese men diagnosed with hyperuricemia in comparison to a non-hyperuricemia group. Methods: We genotyped 47 single nucleotide polymorphisms (SNPs) previously identified to be associated with obesity or metabolic syndrome in 474 adult males (aged ≥ 18 years) using multiplex polymerase chain reaction. Multivariate logistic regression was used to investigate the association between the genetic variations and hyperuricemia. Stratified analyses were applied to further assess the associations. Results: The obesity-related SNP in MSRA rs545854 significantly affected serum uric acid levels. In addition, the G-allele of rs545854 was positively associated with the risk of hyperuricemia [odds ratio (OR) = 2.80, 95% confidence interval (CI) = 1.19-6.64, P = 0.0188]. After adjusting the model for body mass index and central obesity, rs545854 was shown to be an independent factor increasing the risk of hyperuricemia (OR = 2.81, 95%CI = 1.18-6.70, P = 0.0196). Stratified analyses also showed a significant association between rs545854 and hyperuricemia among meat eaters (OR = 2.62, 95%CI = 1.09-6.26, P = 0.0308). Conclusion: The obesity-related SNP rs545854 was correlated with the serum uric acid level and risk of hyperuricemia in a male Chinese population. Therefore, men carrying this SNP could benefit from limiting their meat consumption to prevent hyperuricemia. These findings suggest an underlying genetic link between obesity and hyperuricemia worthy of further exploration.

Hyperuricemia - As a Pathogenetic and Independent Risk Factor in Relation to the Metabolic Syndrome

Introduction: The Metabolic Syndrome is considered at present as one of the most important causes of mortality and morbidity at world level. Even if the uric acid is not part of any definition of the Metabolic Syndrome, the actual studies have shown strong associations between uric acid concentration and the Metabolic Syndrome or its components, the role of Uric Acid within the Metabolic Syndrome (MS) being increasingly investigated.

Aims: We have analyzed recently published data that show the importance of hyperuricemia in MS, Cardiovascular Diseases, Chronic Kidney Disease.

Conclusions: Uric Acid (UA) is a central player in MS progression and in cardiorenal pathology, which is why a multidisciplinary approach and a correct treatment are required, in order to obtain multiple benefits and, possibly, in the future, new therapeutic guidelines in approaching MS.

Asymptomatic hyperuricemia and coronary artery disease in elderly patients without comorbidities

Because many subjects with hyperuricemia have comorbidities, it can be difficult to differentiate the role of hyperuricemia from that of other comorbidities of coronary artery disease (CAD). Subjects aged ≥ 65 years were enrolled in the study and were available at enrollment and at 5-year follow-up. Subjects were excluded if they were overweight or obese, hypertensive, diabetic, hyperlipidemic, had a pre-existing cardiovascular disease, a history of gout or hyperuricemia on medications, or chronic kidney disease as estimated by a glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m². We used Poisson regression to estimate the hazard ratio (HR) for incident CAD events between hyperuricemic (> 7 mg/dL in men and ≥ 6 mg/dL in women) and normouricemic subjects. A total of 2,142 subjects without comorbidities (mean age of 70.7 ± 5.9 years, 1,194 men) were followed for 57.4 ± 8.9 months. Hyperuricemia was associated with an increased cumulative incidence of incident CAD events (15.0% versus 8.8%, P < 0.001). After adjusting for confounding factors, hyperuricemia independently predicted the risk of incident CAD events (HR=1.71, 95% CI 1.26-2.34). In conclusion, asymptomatic hyperuricemia is a valuable biomarker for predicting the development of incident CAD events.

Serum uric acid levels and multiple health outcomes: umbrella review of evidence from observational studies, randomised controlled trials, and Mendelian randomisation studies

Objective To map the diverse health outcomes associated with serum uric acid (SUA) levels.Design Umbrella review.Data sources Medline, Embase, Cochrane Database of Systematic Reviews, and screening of citations and references.Eligibility criteria Systematic reviews and meta-analyses of observational studies that examined associations between SUA level and health outcomes, meta-analyses of randomised controlled trials that investigated health outcomes related to SUA lowering treatment, and Mendelian randomisation studies that explored the causal associations of SUA level with health outcomes.Results 57 articles reporting 15 systematic reviews and144 meta-analyses of observational studies (76 unique outcomes), 8 articles reporting 31 meta-analyses of randomised controlled trials (20 unique outcomes), and 36 articles reporting 107 Mendelian randomisation studies (56 unique outcomes) met the eligibility criteria. Across all three study types, 136 unique health outcomes were reported. 16 unique outcomes in meta-analyses of observational studies had P<10-6, 8 unique outcomes in meta-analyses of randomised controlled trials had P<0.001, and 4 unique outcomes in Mendelian randomisation studies had P<0.01. Large between study heterogeneity was common (80% and 45% in meta-analyses of observational studies and of randomised controlled trials, respectively). 42 (55%) meta-analyses of observational studies and 7 (35%) meta-analyses of randomised controlled trials showed evidence of small study effects or excess significance bias. No associations from meta-analyses of observational studies were classified as convincing; five associations were classified as highly suggestive (increased risk of heart failure, hypertension, impaired fasting glucose or diabetes, chronic kidney disease, coronary heart disease mortality with high SUA levels). Only one outcome from randomised controlled trials (decreased risk of nephrolithiasis recurrence with SUA lowering treatment) had P<0.001, a 95% prediction interval excluding the null, and no large heterogeneity or bias. Only one outcome from Mendelian randomisation studies (increased risk of gout with high SUA levels) presented convincing evidence. Hypertension and chronic kidney disease showed concordant evidence in meta-analyses of observational studies, and in some (but not all) meta-analyses of randomised controlled trials with respective intermediate or surrogate outcomes, but they were not statistically significant in Mendelian randomisation studies.Conclusion Despite a few hundred systematic reviews, meta-analyses, and Mendelian randomisation studies exploring 136 unique health outcomes, convincing evidence of a clear role of SUA level only exists for gout and nephrolithiasis.

Fructose Intake, Serum Uric Acid, and Cardiometabolic Disorders: A Critical Review

There is a direct relationship between fructose intake and serum levels of uric acid (UA), which is the final product of purine metabolism. Recent preclinical and clinical evidence suggests that chronic hyperuricemia is an independent risk factor for hypertension, metabolic syndrome, and cardiovascular disease. It is probably also an independent risk factor for chronic kidney disease, Type 2 diabetes, and cognitive decline. These relationships have been observed for high serum UA levels (>5.5 mg/dL in women and >6 mg/dL in men), but also for normal to high serum UA levels (5-6 mg/dL). In this regard, blood UA levels are much higher in industrialized countries than in the rest of the world. Xanthine-oxidase inhibitors can reduce UA and seem to minimize its negative effects on vascular health. Other dietary and pathophysiological factors are also related to UA production. However, the role of fructose-derived UA in the pathogenesis of cardiometabolic disorders has not yet been fully clarified. Here, we critically review recent research on the biochemistry of UA production, the relationship between fructose intake and UA production, and how this relationship is linked to cardiometabolic disorders.

Serum uric acid levels are associated with obesity but not cardio-cerebrovascular events in Chinese inpatients with type 2 diabetes

We aim to explore the associations between serum uric acid (SUA) and obesity and cardio-cerebrovascular events (CCEs) in Chinese inpatients with type 2 diabetes mellitus (T2DM). 2 962 inpatients with T2DM were stratified into quartile based on SUA concentrations. There were significant increases in the prevalence of both obesity (32.6%, 41.9%, 50.1%, and 62.8%, respectively, p < 0.001 for trend) and severe obesity (0.4%, 0.6%, 0.8%, and 1.3%, respectively, p < 0.001 for trend) across the SUA quartiles. A fully adjusted multiple logistic regression analysis revealed that SUA quartiles were independently associated with the presence of obesity (p < 0.001). The prevalence of CCEs was significantly higher in the obese diabetics than in the nonobese diabetics (16.8% vs. 13.2%, p = 0.027). After controlling for multiple confounding factors, BMI levels were also significantly correlated with the presence of CCEs (p = 0.020). However, there was no significant association of SUA quartiles/SUA levels with the presence of CCEs in T2DM. This study suggested that SUA levels were independently associated with obesity but not with CCEs in patients with T2DM. In selected populations such as subjects with T2DM, the role of uric acid in cardiovascular complications might be attributable to other cardiovascular risk factors, such as obesity.

Clinical and hemodynamic profiles of elderly patients with pulmonary arterial hypertension: a single center, prospective study

BACKGROUNDS

Pulmonary arterial hypertension (PAH) was previously considered an illness that affects mostly the young, but now it is also increasingly recognized in the elderly. The aim of this study was to compare the features of elderly versus younger patients diagnosed with PAH, and to define the prognostic factors which affect their long-term survival.

METHODS

In this prospective, single center study, the clinical, echocardiographic, hemodynamic characteristics, and the outcomes of younger (18-65 years) and elderly (≥ 65 years) patients with definitive diagnosis of precapillary PAH were compared.

RESULTS

A total of 119 patients were analyzed in this study; 43 were elderly (mean age: 71.5 ± 5.5 years), while 76 were non-elderly (mean age 44.5 ± 15.2 years). During the mean follow-up duration of 26.8 ± 25.0 months, 43 deaths occurred, 17 of which were among the elderly group, with 28 among non-elderly group. Comparison of baseline parameters showed that 6 min walking distance, hemoglobin levels, pulmonary artery pressures and pulmonary vascular resistance were significantly lower; and estimated glomerular filtration rate, body mass index, E/e' and pulmonary capillary wedge pressure were significantly higher in the elderly group than in the younger group. Survival analysis demonstrated that the independent predictors of death were tricuspid plane annular systolic excursion (TAPSE; HR: 1.272, 95% CI: 1.079-1.499, P = 0.004) and uric acid (HR: 1.291, 95% CI: 1.042-1.600, P = 0.019) in the elderly group. In contrast, in the non-elderly group, higher brain natriuretic peptide (HR: 1.002, 95% CI: 1.001-1.004, P < 0.001) and higher right atrial pressure (HR: 1.128, 95% CI: 1.026-1.241, P = 0.013) values were the only parameters associated with mortality.

CONCLUSIONS

Our data suggest that elderly PAH patients have a unique clinical and hemodynamic profile, with totally different prognostic markers compared to younger PAH patients.

Serum uric acid levels and cardiovascular disease: the Gordian knot

Hyperuricemia is defined as serum uric acid level of more than 7 mg/dL and blood levels of uric acid are causally associated with gout, as implicated by evidence from randomized clinical trials using urate lowering therapies. Uric acid as a cardiovascular risk factor often accompanies metabolic syndrome, hypertension, diabetes, dyslipidemia, chronic renal disease, and obesity. Despite the association of hyperuricemia with cardiovascular risk factors, it has remained controversial as to whether uric acid is an independent predictor of cardiovascular disease. To settle this issue, and in the absence of large randomized controlled trials, Mendelian randomization analysis in which the exposure is defined based on the presence or absence of a specific allele that influences a risk factor of interest have tried to shed light on this.

Hyperuricemia and coronary heart disease mortality: a meta-analysis of prospective cohort studies

Background

Hyperuricemia may be associated with an increased risk of coronary heart disease (CHD) mortality; however, the results from prospective studies are conflicting. The objective of this study was to assess the association between hyperuricemia and risk of CHD mortality by performing a meta-analysis.

Methods

Pubmed and Embase were searched for relevant prospective cohort studies published until July 2015. Studies were included only if they reported data on CHD mortality related to hyperuricemia in a general population. The pooled adjusted relative risk (RR) was calculated using a random-effects model.

Results

A total of 14 studies involving 341 389 adults were identified. Hyperuricemia was associated with an increased risk of CHD mortality (RR: 1.14; 95 % CI: 1.06–1.23) and all-cause mortality (RR: 1.20; 95 % CI: 1.13–1.28). For each increase of 1 mg/dl of serum uric acid (SUA), the overall risks of CHD and all-cause mortality increased by 20 and 9 %, respectively. According to the gender subgroup analyses, hyperuricemia increased the risk of CHD mortality in women (RR: 1.47; 95 % CI: 1.21–1.73) compared to men (RR: 1.10; 95 % CI: 1.00–1.19). The risk of all-cause mortality was greater in women.

Conclusions

Hyperuricemia may modestly increase the risk of CHD and all-cause mortality. Future research is needed to determine whether urate–lowering therapy has beneficial effects for reducing CHD mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-016-0379-z) contains supplementary material, which is available to authorized users.

Serum uric acid and low-density lipoprotein cholesterol levels are independent predictors of coronary artery disease in Asian Indian patients with type 2 diabetes mellitus

Aim:

We aimed to identify the predictors of coronary artery disease (CAD) in patients with type 2 diabetes mellitus (type 2 DM).

Methods:

About fifty Asian Indian patients with type 2 DM patients aged >40 years and fifty sex- and age-matched nondiabetic controls were enrolled for this study. Following complete medical history and baseline clinical data, laboratory investigations were performed to assess fasting and postprandial plasma glucose levels, lipid profile, blood urea, serum creatinine, and serum uric acid levels.

Results:

Body mass index (BMI), waist-to-hip ratio, serum uric acid, serum total cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, very LDL cholesterol were significantly higher among diabetic patients compared to controls. On univariate analysis, serum LDL cholesterol (odds ratio [OR]: 29.67, P < 0.001), serum uric acid (OR: 25.65, P < 0.001), low high-density lipoprotein (HDL) cholesterol (OR: 21.12, P < 0.001), hypertension (OR: 17.06, P < 0.001), family history of cardiovascular disease (CVD) (OR: 9.43, P = 0.002), and duration of diabetes (OR: 4.65, P = 0.03) were identified as predictors of CVD among diabetic patients. On multivariate regression, only LDL cholesterol (OR: 1.51, P = 0.002) and serum uric acid (OR: 1.21, P = 0.01) were the independent predictors of CAD among diabetic patients. Significant positive correlation of serum uric acid with duration of diabetes (r = 0.38, P = 0.006), BMI (r = 0.35, P = 0.01), triglycerides (r = 0.356, P = 0.01), LDL cholesterol (r = 0.38, P = 0.007), HDL cholesterol (r = −0.514, P < 0.001), and hypertension (r = 0.524, P < 0.001) was observed.

Conclusion:

Serum LDL cholesterol and hyperuricemia may serve as independent predictors of CAD among Asian Indian subjects with type 2 DM.

Association between Serum Uric Acid and Mortality among Chinese Patients with Coronary Artery Disease

OBJECTIVES

Several studies have investigated the association between serum uric acid (SUA) and the risks of coronary artery disease (CAD) but have yielded inconsistent results. The aim of this study was to assess whether there is an independent association of SUA with all-cause and cardiovascular disease (CVD) mortality in Chinese patients with CAD.

METHODS

A prospective cohort study of 1,799 patients was conducted. Cox regression models were used to estimate the association of SUA with the risk of death.

RESULTS

During a median follow-up of 3.9 years, 177 deaths were recorded and 126 of these were due to CVD. Patients in the highest SUA quartile had a 2.43-fold risk of all-cause mortality and a 2.44-fold risk of CVD mortality compared with those in the lowest quartile. In the subpopulation analysis, the association between SUA and mortality remained similar when participants were stratified by age, gender, body mass index and type of CAD. In contrast, we found a significant interaction with estimated glomerular filtration rate (eGFR). There was a stronger association between SUA and the risk of all-cause and CVD mortality among patients with an eGFR ≥60 ml/min/1.73 m2, but no significant association was found in the population with an eGFR <60 ml/min/1.73 m2.

CONCLUSIONS

Elevated SUA levels were positively associated with an increased risk of all-cause and CVD mortality among CAD patients.

A genetic marker of hyperuricemia predicts cardiovascular events in a meta-analysis of three cohort studies in high risk patients

INTRODUCTION

The strongest genetic marker of uric acid levels, the rs734553 SNP in the GLUT9 urate transporter gene, predicts progression to kidney failure in CKD patients and associates with systolic BP and carotid intima media thickness in family-based studies.

METHODS

Since genes are transmitted randomly (Mendelian randomization) we used this gene polymorphism as an unconfounded research instrument to further explore the link between uric acid and cardiovascular disease (cardiovascular death, and non-fatal myocardial infarction and stroke) in a meta-analysis of three cohort studies formed by high risk patients (MAURO: 755 CKD patients; GHS: 353 type 2 diabetics and coronary artery disease and the TVAS: 119 patients with myocardial infarction).

RESULTS

In separate analyses of the three cohorts, the incidence rate of CV events was higher in patients with the rs734553 risk (T) allele (TT/GT) than in those without (GG patients) and the HR in TT/GT patients in the three cohorts (range 1.72-2.14) coherently signaled an excessive cardiovascular risk with no heterogeneity (I2 = 0.01). The meta-analytical estimate (total number of patients, n = 1227; total CV events, n = 222) of the HR for the combined end-point in TT/GT patients was twice higher (pooled HR: 2.04, 95% CI: 1.11-3.75, P = 0.02) than in GG homozygotes.

CONCLUSIONS

The T allele of the rs734553 polymorphism in the GLUT9 gene predicts a doubling in the risk for incident cardiovascular events in patients at high cardiovascular risk. Findings in this study are compatible with the hypothesis of a causal role of hyperuricemia in cardiovascular disease in high risk conditions.

Relationship Between Hyperuricemia and Cardiovascular Disease Risk Factors in a Chinese Population: A Cross-Sectional Study

BACKGROUND

To study the relationship between hyperuricemia and cardiovascular diseases (CVDs) risk factors in a Chinese population.

MATERIAL AND METHODS

Data analyzed in this study were from the Chinese Hyperuricemia and Gout Database. Indicators of serum uric acid (SUA) level, height, weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), smoking status, alcohol consumption, blood glucose, cholesterol, and triglycerides were measured. T test, one-way analysis of variance, Pearson's correlation, multivariate linear regression, and multivariate logistic regression were used.

RESULTS

Compared with normouricemic men, hyperuricemic men had greater height (P<0.01), weight (P<0.001), body mass index (BMI) (P<0.001), SBP (P<0.01), DBP (P<0.001), cholesterol (P<0.01), and triglyceride (P<0.001). Compared with normouricemic women, hyperuricemic women were older (P<0.01) and had greater weight (P<0.05), BMI (P<0.01), SBP (P<0.01), DBP (P<0.05), glucose (P<0.05), and triglyceride (P<0.001). In men, an increase of 1 mg/dL in SUA was associated with a 0.279 kg/m2 increase in BMI (P<0.001), a 2.438 mg/dL increase in cholesterol (P<0.05), a 10.358 mg/dL increase in triglyceride (P<0.001), and a 3.1 mg/dL decrease in glucose (P<0.01). In women, an increase of 1 mg/dL SUA was associated with a 0.168 kg/m2 increase in BMI (P<0.01) and a 3.708 mg/dL increase in triglyceride (P<0.01). After adjustment, SUA was strongly associated with obesity and hyperlipidemia in both sexes.

CONCLUSIONS

Elevated serum uric acid concentration was strongly associated with obesity and hyperlipidemia in both men and women. These results indicated that, among hyperuricemia patients, we should pay more attention to the possibility of cardiovascular complications. These results might provide a novel target or a possible new treatment for cardiovascular diseases by lowering the level of serum uric acid.

Relation of serum uric acid to cardiovascular disease

This review summarizes recent published literature on the association between serum uric acid and cardiovascular disease, a relationship which is complex and not fully elucidated. Uric acid may be a marker for risk, a causative agent in cardiovascular disease, or both. Various biologic factors can influence serum uric acid levels, and serum uric acid level itself is closely related to conditions such as hypertension, dyslipidemia, obesity, and impaired glucose metabolism, that contribute to cardiovascular disease pathophysiology. Serum uric acid levels have been found to be associated with adverse outcomes, including mortality, in the general population. In addition, serum uric acid is associated with increased risk for incident coronary heart disease, heart failure, and atrial fibrillation. In the setting of established systolic heart failure, serum uric acid is positively associated with disease severity and mortality risk. Whether targeting treatment based on uric acid levels might affect clinical outcomes is still being studied.

Is hyperuricemia a risk factor for arteriosclerosis? Uric acid and arteriosclerosis in apolipoprotein e-deficient mice

Although hyperlipidemia, high blood pressure, and diabetes increase the risk of arteriosclerosis, it is not clear whether hyperuricemia increases the risk of arteriosclerosis or not. We examined the effects of uric acid and curative drugs for hyperuricemia on atherosclerosis-susceptible C57BL/6J apolipoprotein E-deficient (apoE(-/-)) mice. Male apoE(-/-) mice (age: 6 weeks) were fed a normal diet (normal diet group) or a uric acid-enriched diet. Mice fed the uric acid-enriched diet were divided into three groups and administered a drinking vehicle (high uric acid diet group), allopurinol (20 mg·kg(-1)·d(-1)), or benzbromarone (20 mg·kg(-1)·d(-1)) for 10 weeks. Serum uric acid concentrations were higher in the high uric acid diet group than in the normal diet group, and concentrations in the allopurinol and benzbromarone groups were lower than in the high uric acid diet group. Serum total cholesterol and triglyceride levels were lower in the allopurinol group than in the high uric acid diet group. Oxidative stress was lower in the benzbromarone group than in the high uric acid diet group. Atherosclerotic lesion areas were smaller in the allopurinol and benzbromarone groups than in the high uric acid diet group. Thus, hyperuricemia may not be an independent risk factor for arteriosclerosis; however, the administration of allopurinol and benzbromarone prevented the development of atherosclerosis in apoE(-/-) mice fed a uric acid-enriched diet. The anti-atherosclerotic effect was in part due to lower total cholesterol and oxidative stress in the serum. Other possible mechanisms underlying this effect should be investigated.

Why focus on uric acid?

In gouty patients, urate lowering therapies (ULTs) are recommended to bring serum uric acid (SUA) levels below 6.0 mg/dL, with the aim of dissolving urate depositions, thereby reducing disease impact. However, patients with hyperuricemia often present with other conditions associated with cardiovascular (CV) risk, such as high blood pressure, obesity, insulin resistance, fatty liver, and chronic kidney disease. In the last decade, several well grounded pieces of evidence showed that the elevation of uric acid often occurs prior to the development of hypertension or metabolic syndrome, thus suggesting a direct association between elevated SUA and these conditions. This paper will discuss available evidence supporting the key role of serum uric acid in the development of CV and renal disease, with a focus on the molecular mechanisms underlying this causative association. This review is based on a PubMed/Embase database search for articles on hyperuricemia and its impact on cardiovascular and renal function.

Relationship between serum uric acid and electrocardiographic alterations in a large sample of general population: data from the Brisighella Heart Study

INTRODUCTION

Serum uric acid (SUA) may contribute to the increased cardiovascular damage through direct injury to the endothelium and alteration of cardiovascular function.

AIM

To evaluate the association of SUA with the presence of the most recurrent electrographic alterations and with the length of the main ECG intervals in a large sample of general population.

METHODS

For this study, on the database of the Brisighella Heart Study, we evaluated the available data of 790 men and 849 women, excluding subjects affected by gout or taking antihyperuricemic agents, those taking drug increasing the QT interval and those using beta-blockers or non-dihydropyridine calcium channel blockers at the moment of the ECG registration. Multiple ascending stepwise regression analyses were carried out to determine the independent predictors of the predefined ECG alterations.

RESULTS

The prevalence of predefined ECG alterations was comparable between genders, with the exception of sinus bradicardia, left-anterior fascicular block, atrio-ventricular blocks and left ventricular hypertrophy (LVH), which appeared to be more frequent in men. The multivariate analysis revealed that SUA was associated to ischaemic alterations, LVH, sinus tachycardia and tachyarrhytmias. Age was associated to all evaluated ECG alterations beyond sinus tachycardia and LVH. Male sex was associated to sinus bradicardia, atrio-ventricular blocks, anterior-left fascicular block and LVH. Blood pressure was associated to different ECG alterations, but with clinically relevant OR with ischaemic alterations and LVH.

CONCLUSION

SUA level is related the prevalence of both organic and rhythm ECG alterations in a wide sample of general population.

Uric acid, hypertension, and cardiovascular and renal complications

Over the last decade, the biologic interference of uric acid with the cardiovascular (CV) system and the kidney has been intensively investigated, and several experimental studies in animal models and in vitro documented that hyperuricemia may trigger hypertension and incite endothelial dysfunction, vascular damage and renal disease. A substantial proportion of epidemiological studies are compatible with the hypothesis that hyperuricemia may be noxious to the CV system and the kidney as well. However, there are still no well-powered trials testing whether uric acid-lowering interventions may reduce BP or attenuate the risk for adverse CV and renal outcomes. Evidence still remains largely insufficient to recommend changes in the current policy of not prescribing uric acid-lowering drugs to individuals with asymptomatic hyperuricemia.

Treatment of Asymptomatic Hyperuricemia and Prevention of Vascular Disease: A Decision Analytic Approach

Objective.

Elevated serum urate may be associated with an increase in cardiovascular (CV) disease. Treating asymptomatic hyperuricemia with urate-lowering drugs such as allopurinol may reduce CV events. We designed a model to simulate the effect of allopurinol treatment on reducing frequency of CV events in individuals with elevated serum urate.

Methods.

A Markov state-transition model was constructed to assess occurrence of vascular events (VE) for 2 treatment strategies: treat all asymptomatic individuals with allopurinol (Treat All) and treat only if symptomatic (Treat Symptomatic). The model simulated a hypothetical cohort of 50-year-old men with different serum urate concentrations (6–6.9 and 7–7.9 mg/dl) followed over 20 years. Age and sex subgroups were analyzed. Model inputs were derived from current literature. The main outcome measures were mean number of VE and mean number of deaths from VE.

Results.

For 50-year-old men with serum urate 6.0–6.9 mg/dl, individuals in the Treat All strategy have a 30% reduction in the mean number of VE compared to those in the Treat Symptomatic strategy (mean VE: 0.078 vs 0.11), and a 39% reduction in mean number of deaths from VE. At higher serum urate concentrations, treatment is more effective in reducing the mean number of VE and mean number of deaths from VE (38% event, 54% death). Results for women show similar trends. As the cohort ages, treatment has less effect on reducing VE. The number needed to treat to prevent 1 event is 20 (men, 7.0–7.9 mg/dl).

Conclusion.

The model predicts that treating asymptomatic hyperuricemia with allopurinol is most effective in preventing VE at a serum urate above 7.0 mg/dl in men and 5.0 mg/dl in women.

The associations of uric acid, cardiovascular and all-cause mortality in peritoneal dialysis patients

AIMS

To investigate whether uric acid (UA) is an independent predictor of cardiovascular (CV) and all-cause mortality in peritoneal dialysis (PD) patients after controlling for recognized CV risk factors.

METHODS

A total of 2264 patients on chronic PD were collected from seven centers affiliated with the Socioeconomic Status on the Outcome of Peritoneal Dialysis (SSOP) Study. All demographic and laboratory data were recorded at baseline. Multivariate Cox regression was used to calculate the hazard ratio (HR) of CV and all-cause mortality with adjustments for recognized traditional and uremia-related CV factors.

RESULTS

There were no significant differences in baseline characteristics between patients with (n = 2193) and without (n = 71) UA measured. Each 1 mg/dL of increase in UA was associated with higher all-cause mortality with 1.05(1.00∼1.10) of HR and higher CV mortality with 1.12 (1.05∼1.20) of HR after adjusting for age, gender and center size. The highest gender-specific tertile of UA predicted higher all-cause mortality with 1.23(1.00∼1.52) of HR and higher CV mortality with 1.69 (1.21∼2.38) of HR after adjusting for age, gender and center size. The predictive value of UA was stronger in patients younger than 65 years without CV disease or diabetes at baseline. The prognostic value of UA as both continuous and categorical variable weakened or disappeared after further adjusted for uremia-related and traditional CV risk factors.

CONCLUSIONS

The prognostic value of UA in CV and all-cause mortality was weak in PD patients generally, which was confounded by uremia-related and traditional CV risk factors.

Uric acid is a risk factor for ischemic stroke and all-cause mortality in the general population: a gender specific analysis from The Tromsø Study

BACKGROUND

The role of serum uric acid as an independent predictor of cardiovascular disease and death is uncertain in the general population. Adjustments for additional cardiovascular risk factors have not been consistent. We examined the association of serum uric acid with all-cause mortality, ischemic stroke and myocardial infarction in a prospective population based study, with several traditional and non-traditional risk factors for cardiovascular disease included in the model.

METHODS

A population-based prospective cohort study was performed among 2696 men and 3004 women. Endpoints were all-cause mortality after 15 years, and fatal or non-fatal myocardial infarction (MI) and ischemic stroke after 12 years.

RESULTS

1433 deaths, 659 MIs and 430 ischemic strokes occurred during follow-up. Fully adjusted Cox regression analyses showed that per 1 SD (87 μmol/L) increase in serum uric acid level, the risk of all-cause mortality increased in both genders (hazard ratios, HR men; 1.11, 95% CI 1.02-1.20, women; 1.16, 1.05-1.29). HRs and 95% CI for stroke were 1.31, 1.14-1.50 in men, 1.13, 0.94-1.36 in women, and 1.22 (1.09, 1.35) in the overall population. No independent associations were observed with MI.

CONCLUSION

Serum uric acid was associated with all-cause mortality in men and women, even after adjustment for blood pressure, estimated GFR, urinary albumin/creatinine ratio, drug intake and traditional cardiovascular risk factors. After the same adjustments, serum uric acid was associated with 31% increased risk of stroke in men.

Hyperuricemia is independently associated with endothelial dysfunction in postmenopausal women but not in premenopausal women

OBJECTIVES

The purpose of this study was to determine the relationships between uric acid, endothelial function and cardiovascular risk factors and to investigate whether menopausal status was associated with the relationship between uric acid and endothelial function in women.

DESIGN

Cross-sectional study.

SETTING

3 general hospitals in Japan.

PARTICIPANTS

749 Japanese women aged 30-74 years recruited from people who underwent health-screening examinations with agreement for measurement of vascular function.

MEASURES

We measured serum concentrations of uric acid and flow-mediated vasodilation (FMD). Percentage of FMD (peak diameter-baseline diameter/baseline diameter) was used for analysis. Endothelial dysfunction was defined as FMD ≤4.90%, division point for the lowest tertile and the middle tertile of FMD. Menopause women were defined as participants without menstruation for over 1 year or participants with a history of hysterectomy or bilateral oophorectomy.

RESULTS

Of the 749 participants, 368 (49.1%) were premenopausal women and 381 (50.9%) were postmenopausal women. Age, body mass index, systolic blood pressure, total cholesterol, triglycerides, glucose, estimated glomerular filtration rate and Framingham risk score were significantly correlated with serum uric acid level. FMD showed a gradual decrease in accordance with the serum uric acid level in the entire study population (<4 mg/dL, 6.85±3.65%; 4 to <5 mg/dL, 6.79±3.60%; 5 to <6 mg/dL, 6.24±3.58%; ≥6 mg/dL, 5.27±3.18%; p=0.01). Multivariate analysis revealed that uric acid was a significantly independent risk factor for endothelial dysfunction in postmenopausal women (OR 1.23, 95% CI 1.01 to 1.50), but not in premenopausal women.

CONCLUSIONS

These findings suggest that uric acid can be used as a risk marker of endothelial dysfunction in a female population, and particularly as an independent risk factor in postmenopausal women but not in premenopausal women.

REGISTRATION NUMBER OF THE STUDY

UMIN000003409.

Relationship between serum uric acid and all-cause and cardiovascular mortality in patients treated with peritoneal dialysis

BACKGROUND

Although serum uric acid level appears to be associated with mortality in individuals treated with hemodialysis, the relationship between serum uric acid level and death is uncertain in patients treated with peritoneal dialysis (PD).

STUDY DESIGN

Cohort study.

SETTING & PARTICIPANTS

985 patients from a single PD center in South China followed up for a median of 25.3 months.

PREDICTOR

Serum uric acid level.

OUTCOMES & MEASUREMENTS

The association of baseline sex-specific uric acid level with all-cause and cardiovascular mortality was evaluated. Models were adjusted for age, body mass index, comorbidity score, residual kidney function, total Kt/V, allopurinol and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use, and laboratory test results, including hemoglobin, serum albumin, creatinine, calcium, phosphorus, triglycerides, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein.

RESULTS

Mean age was 48.3±15.4 (SD) years, and 23% had diabetes. Mean uric acid level was 7.0±1.3 (range, 3.8-19.8) mg/dL. During follow-up, 144 deaths were recorded, of which 64 were due to cardiovascular events. In multivariable models, the highest sex-specific tertile of uric acid level was associated with increased risk of all-cause mortality (HR, 1.93; 95% CI, 1.27-2.93; P=0.004) and cardiovascular mortality (HR, 3.31; 95% CI, 1.70-6.41; P<0.001) compared to the lowest tertile. Adjusted Cox regression models showed that the HRs per 1-mg/dL higher uric acid level for all-cause and cardiovascular mortality were 1.33 (95% CI, 1.14-1.56; P<0.001) and 1.44 (95% CI, 1.17-1.77; P=0.001) for men and 1.03 (95% CI, 0.86-1.24; P=0.8) and 1.16 (95% CI, 0.97-1.38; P=0.1) for women, respectively. A formal test for interaction indicated that the association of uric acid level with all-cause and cardiovascular mortality differed by sex (β = -0.06 [P=0.02] and β = -0.10 [P=0.02], respectively).

LIMITATIONS

Single measurement of uric acid at baseline. Cause of death determined by death certificates and expert consensus.

CONCLUSIONS

Elevated serum uric acid level is an independent risk factor for all-cause and cardiovascular mortality in men treated with PD.

The Impacts of Serum Uric Acid on arterial hemodynamics and Cardiovascular Risks

Hyperuricemia, and its clinical manifestation gout, is a metabolic disease process that has been recognized since the dawn of medical inquiry. Uric acid was hypothesized to be a mediator of cardiovascular disease for period of time. Epidemiological correlations of hyperuricemia with hypertension and cardiovascular events were evident for two centuries' studies. With recent animal studies shedding light on the causal mechanisms of hypertension, and clinical trials suggesting that urate-lowering therapy can lower blood pressure, there appears to be growing evidence of a connection between hyperuricemia and cardiovascular disease. To help bring this recent uric acid research into context, we have undertaken this narrative review of hyperuricemia, hypertension, its hemodynamics and its outcomes, and the risk for cardiovascular diseases.

KEY WORDS

Cardiovascular risk; Hemodynamics; Uric acid.

The role of uric acid in the pathogenesis of human cardiovascular disease

Hyperuricaemia is common in subjects with cardiovascular disease, but is not commonly considered a true risk factor. Recent studies suggest that uric acid is biologically active and can stimulate oxidative stress, endothelial dysfunction, inflammation and vasoconstriction. Epidemiological studies have found that uric acid can independently predict the development of hypertension, as well as stroke and heart failure. Experimentally raising uric acid in animals increases blood pressure, and pilot studies suggest that lowering uric acid in humans can reduce blood pressure in hypertensive individuals. Uric acid may also have emerging roles in the pathogenesis of kidney disease, metabolic syndrome and diabetes. More studies need to be performed on the pathophysiology and clinical consequences of hyperuricaemia in cardiovascular disease.

Effects of menopause and hormone replacement therapy on the associations of hyperuricemia with mortality

OBJECTIVE

Serum uric acid (SUA) levels have been associated with cardiovascular and all-cause mortality. It remains unclear whether these associations differ by gender, menopausal status and hormone replacement therapy (HRT) and whether they persist after adjustment for known cardiovascular risk factors.

METHODS

We determined the associations between fasting SUA level and death certificate-based mortality among 5856 participants of the third US National Health and Nutrition Examination Survey aged ≥20 years recruited between 1988 and 1994 and followed for mortality until December 2006 (mean follow-up: 13.5 years; maximum follow-up: 18 years). Cox proportional hazards regression analysis was used to adjust for demographic characteristics, cardiovascular risk factors and other variables potentially associated with SUA levels.

RESULTS

Among women, SUA level was associated with all-cause and cardiovascular mortality (adjusted hazard ratio [AHR] 1.17, 95% CI 1.03-1.32 and AHR 1.23 (1.01-1.51) respectively per unit increase in SUA. These associations persisted among postmenopausal but not premenopausal women. Furthermore, among postmenopausal women, significant associations were identified between SUA and all-cause (AHR 1.30 [1.11-1.51]) or cardiovascular (AHR 1.61 [1.33-1.94]) mortality only among women not taking HRT, but not among women on HRT. We did not identify associations between SUA levels and all-cause or cardiovascular mortality in men, either under or over 51 years of age, in unadjusted or adjusted analyses.

CONCLUSIONS

SUA level predicts cardiovascular and all-cause mortality independently of major predictors and risk factors in postmenopausal women not taking HRT but not in premenopausal women, postmenopausal women on HRT, or men.

Serum uric acid is an independent risk factor for cardiovascular disease and mortality in hypertensive patients

The purpose of the study was to investigate the association of serum uric acid (UA) levels in hypertensive patients with the prognosis for cardiovascular disease (CVD) and mortality. This hospital-based cohort study included 669 patients with essential hypertension. A questionnaire was used to identify patients in whom hypertensive complications had occurred, as well as causes of death. The primary end point of this study was new onset of stroke or CVD (new onset of angina pectoris, myocardial infarction or heart failure). We evaluated the baseline characteristics of patients, including UA levels, and assessed whether UA levels could be used to predict stroke and CVD. We also classified subjects into four groups according to the serum UA levels. During a mean follow-up period of 7.1±0.1 years, 71 strokes, 58 cases of CVD and 64 deaths were recorded. Kaplan-Meier analysis revealed that subjects in the high UA group had a higher frequency of stroke and CVD (P=0.0120) and total mortality (P=0.0021). A Cox proportional hazard model determined that, after adjusting for traditional risk factors, serum UA levels were predictive of CVD (relative risk=1.30; P=0.0073), stroke and CVD (relative risk=1.19; P=0.0141), mortality (relative risk=1.23; P=0.0353) and stroke CVD and mortality (relative risk=1.19; P=0.0083), but not stroke (P=0.4268). The significant correlations were particularly marked in women. Serum UA levels may be an independent risk factor for stroke and CVD in patients with essential hypertension, particularly women.

Urate transporter gene SLC22A12 polymorphisms associated with obesity and metabolic syndrome in Caucasians with hypertension

BACKGROUND/AIMS

Hyperuricemia is associated with obesity and the metabolic syndrome. URAT1 is a urate transporter, and we tested the association of URAT1 transporter gene (SLC22A12) polymorphisms with obesity and the metabolic syndrome in hypertensive subjects.

METHODS

Patients with essential hypertension (n = 414) from a randomized controlled study were genotyped for SLC22A12 SNPs rs11602903, rs505802 and rs11231825.

RESULTS

In Caucasians, SLC22A12 SNPs were associated with the body mass index (BMI). rs11602903 was associated with BMI (p < 0.0001), waist circumference (p = 0.003), HDL cholesterol (p = 0.018) and the metabolic syndrome (p = 0.033), and accounted for 7% of the variation of BMI in Caucasians. In African Americans, SLC22A12 SNP rs11602903 was not associated with BMI, waist circumference, HDL cholesterol or triglycerides.

CONCLUSION

The URAT1 gene SLC22A12 polymorphism may play a role in obesity and the metabolic syndrome in Caucasian hypertensive subjects.