Hyperuricemia and uncontrolled hypertension in treated hypertensive patients: K-MetS Study

Relationship between hyperuricemia and the risk of cardiovascular events and chronic kidney disease in both the general population and hypertensive patients: A systematic review and meta-analysis

BACKGROUND

To explore the relationships between hyperuricemia and the risk of cardiovascular diseases (CVD) and chronic kidney disease (CKD) in both the general population and hypertensive patients through meta-analysis.

METHODS AND RESULTS

We systematically searched PubMed, Embase, and Cochrane Library databases from January 2012. The eligibility criteria were predefined, and quality was assessed using the Newcastle-Ottawa Scale (NOS). Stata 15.1 was used for meta-analysis, heterogeneity and sensitivity analysis. Subgroup analysis was used to explore heterogeneity, funnel plots and Egger tests were used to assesse publication bias and applicability. A total of 10,662 studies were retrieved, 45 of which were included in this meta-analysis utilizing a random effects model. Hyperuricemia was significantly associated with an increased risk of new-onset hypertension (RR = 1.36, 95% CI 1.16-1.59; I2 = 98.8%), total CVD (RR = 1.53, 95% CI 1.23-1.89; I2 = 93.7%), stroke (RR = 1.97, 95% CI 1.71-2.26, I2 = 0.0%), coronary heart disease (CHD) (RR = 1.56, 95% CI 1.06-2.30, I2 = 93.3%), and CKD (RR = 1.71, 95% CI 1.56-1.87; I2 = 87.3%). However, subgroup analysis showed no significant associations between hyperuricemia and hypertension in non-Asian populations (RR = 0.88, 95% CI 0.59-1.33), or between hyperuricemia and CVD with a follow-up duration <5 years (RR = 1.26, 95% CI 0.97-1.63). Among hypertensive patients, hyperuricemia was significantly associated with total CVD (RR = 2.32, 95% CI 1.31-4.12, I2 = 90.2%), but not with stroke (RR = 1.48, 95% CI 0.86-2.55; I2 = 90.7%) or CHD (RR = 1.51, 95% CI 0.98-2.33; I2 = 71.7%).

CONCLUSION

Hyperuricemia was significantly associated with an increased risk of new-onset hypertension, total CVD, stroke, CHD, and CKD in the general population. Among hypertensive patients, hyperuricemia was associated with an increased risk of CVD but not stroke or CHD alone.

REGISTRATION NUMBER

CRD42022370692.

Carvacrol Alleviates Hyperuricemia-Induced Oxidative Stress and Inflammation by Modulating the NLRP3/NF-κB Pathwayt

Purpose

Gouty arthritis is generally induced by the accumulation of monosodium urate (MSU) crystals in the joints due to elevated serum uric acid levels, potentially leading to serious pathological disorders such as nephrolithiasis, renal failure, and acute gouty arthritis. In this study, we aimed to validate the anti-gout effects of carvacrol, a phenolic monoterpene.

Materials and Methods

Male Sprague–Dawley rats were divided into normal saline, disease group by injecting potassium mono-oxonate (PO) at a dose of 250 mg/kg, and three treatment groups, either with carvacrol 20 mg/kg or 50 mg/kg and 10 mg/kg allopurinol. The blood and tissue samples were subsequently collected and analyzed using different biochemical and histopathological techniques.

Results

Our results revealed a significant increase in the serum levels of oxidative stress-related markers, namely, uric acid and C-reactive protein (CRP), and NLRP3 inflammasome-dependent inflammatory mediators, including nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α). Carvacrol administration for seven consecutive days exhibited significant anti-hyperuricemic and anti-inflammatory effects in a dose-dependent manner. Notably, the 50 mg/kg carvacrol treatment was observed to produce results similar to the allopurinol treatment. Furthermore, the renal safety of carvacrol was confirmed by the renal function test.

Conclusion

Carvacrol potentially alleviates hyperuricemia-induced oxidative stress and inflammation by regulating the ROS/NRLP3/NF-κB pathway, thereby exerting protective effects against joint degeneration.

Prevalence of Hypertension in Sudanese Patients With Gouty Arthritis

Background In this study, we aimed to study the frequency of hypertension in Sudanese patients with gouty arthritis attending the largest three tertiary hospitals in Khartoum and correlate it with serum uric acid levels. Methodology An observational, descriptive, cross-sectional, hospital-based study was conducted in rheumatology clinics in Khartoum state, Sudan, from August 2020 to January 2021 involving 100 participants. Data were collected, prepared, and analyzed using SPSS version 25.0 (IBM Corp., Armonk, NY, USA). Results In this study, 100 participants were enrolled. The majority were males (79%), with 45% of the participants in the age group of 61-75 years. Overall, 89% of participants had symptoms of gouty arthritis, with the knee being the most common joint affected in 27% of participants. Most participants had a uric acid level above the target (6 mg/dL). The most frequently used uric acid lowering agent was found to be allopurinol in 85% of the patients. Furthermore, among those with gouty arthritis, 51% had hypertension with nearly half being insufficiently controlled. The frequency of undiagnosed hypertension among the participants was found to be 19%, which was statistically significant among gouty arthritis patients (p-value < 0.0001). Upon further analysis of our hypertensive participants, 79.5% of males (n = 35) had high blood pressure levels, which was statistically significant as well (p-value = 0.005), with the highest prevalence being among the age group of 61-75 years. Of those who were hypertensive, 51% had a history of concomitant comorbidity. Overall, 90% of the hypertensive participants (n = 40) had joint symptoms. Moreover, serum uric acid level was above the target in 93% of the participants. Conclusions Hypertension was found to be the most frequently recognized comorbidity in gouty arthritic patients, with more than a third remaining undiagnosed. Moreover, the male gender was a significant risk factor for hypertension among the gouty arthritis participants. Nevertheless, most patients with high blood pressure levels had concurrent elevated uric acid levels.

Association Between Serum Uric Acid and Carotid Intima-Media Thickness in Different Fasting Blood Glucose Patterns: A Case-Control Study

Our objective was to analyze the correlation between serum uric acid (SUA) levels and carotid intima-media thickness (CIMT) and explore the relationship between SUA and carotid atherosclerosis in different glucose metabolism patterns. A total of 614 patients were enrolled in this case-control study, including 406 in the normouricemia group and 208 in the hyperuricemia group. The two groups were each divided into three groups according to fasting blood glucose (FBG) level: normal, impaired fasting glucose (IFG), and diabetes mellitus (DM). CIMT and the CIMT thickening rate in the hyperuricemia group were significantly higher than those in the normouricemia group: 0.17 (0.11-0.24) cm vs. 0.12 (0.08-0.15) cm and 73.56% vs. 51.97% (p < 0.001). Pearson's correlation analysis showed that age, systolic blood pressure (SBP), diastolic blood pressure, FBG, triglyceride, SUA, creatinine, and blood urea nitrogen were positively correlated with CIMT, whereas high-density lipoprotein cholesterol and total cholesterol were negatively correlated with CIMT. Multiple linear regression analysis showed that age, SUA, FBG, and SBP were independent factors that affected CIMT. Furthermore, age and SBP were independent factors in the normouricemia group, and FBG was an independent factor that affected CIMT in the hyperuricemia group (p < 0.05). In the hyperuricemia group, CIMT in the DM group was significantly higher than that in the normal group [0.20 (0.14-0.25)cm vs. 0.15 (0.1-0.25); p < 0.05], and the CIMT thickening rate in the DM group was significantly higher than those in the IFG and normal groups (90.38% vs. 78.38%, 90.38% vs. 65.81%; p < 0.05). The ROC curve analysis showed that uric acid combined with age, SBP, and FBG had the highest area under the curve (AUC) for predicting CIMT thickening [0.855 (95% confidence interval (CI): 0.804-0.906)], followed by uric acid combined with FBG [AUC: 0.767 (95% CI: 0.726-0.808)]. In conclusion, SUA was closely associated with an increase in CIMT in patients with specific FBG metabolic patterns and may be an independent risk factor for carotid atherosclerosis. SUA, especially in combination with other factors (such as age, SBP, FBG), may serve as a specific model to help predict the incidence of CIMT thickening. Clinical Trial Registration: http://www.chictr.org.cn, identifier ChiCTR2000039124.

Structural and Functional Alterations of Gut Microbiota in Males With Hyperuricemia and High Levels of Liver Enzymes

Objective: To investigate the correlation between the structure and function alterations of gut microbiota and biochemical indicators in males with hyperuricemia (HUA) and high levels of liver enzymes, in order to provide new evidences and therapeutic targets for the clinical diagnosis and treatment of HUA. Methods: A total of 69 patients with HUA (HUA group) and 118 healthy controls were enrolled in this study. Their age, height, waist circumference, weight, and pressure were measured. The clinical parameters such as fasting plasma glucose (FBG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), serum uric acid (SUA), serum creatinine (Scr), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), white blood cell (WBC), platelet (PLT), and absolute value of neutrophils (NEUT) were examined. We used whole-genome shotgun sequencing technology and HUMAnN2 MetaCyc pathway database to detect the composition and pathways of the gut microbiota. The main statistical methods were student's t test, chi-square tests, and Wilcoxon rank sum test. The correlations among bacterial diversity, microbial pathways, and biochemical indicators were evaluated by the R function "cor.test" with spearman method. Results: The gut bacterial diversity in HUA group reduced significantly and the community of the microbiota was of significant difference between the two groups. The pathways that can produce 5-aminoimidazole ribonucleotide (PWY-6122, PWY-6277, and PWY-6121), aromatic amino acids, and chorismate (COMPLETE-ARO-PWY, ARO-PWY, and PWY-6163) were enriched in the HUA group; while the pathways that can produce short-chain fatty acids (SCFAs, such as CENTFERM-PWY and PWY-6590) and the gut microbiotas that can produce SCFAs (Roseburia hominis, Odoribacter splanchnicus, Ruminococcus callidus, Lachnospiraceae bacterium 3_1_46FAA, Bacteroides uniformis, Butyricimonas synergistica) and equol (Adlercreutzia equolifaciens) were enriched in healthy controls. Conclusion: The structure and function of the gut microbiota in males with HUA and high levels of liver enzymes have altered apparently. In-depth study of related mechanisms may provide new ideas for the treatment of HUA.

Insulin resistance surrogates predict hypertension plus hyperuricemia

AIMS/INTRODUCTION

To compare the association of hypertension plus hyperuricemia with four insulin resistance surrogates, including glucose and triglycerides (TyG index), TyG index with body mass index (TyG-BMI), the ratio of triglycerides divided by high-density lipoprotein cholesterol (TG/HDL-C) and metabolic score for insulin resistance (METS-IR).

MATERIALS AND METHODS

Data from a cross-sectional epidemiological study enrolling a representative population sample aged ≥65 years were used to calculate the four indexes. The association with hypertension plus hyperuricemia and insulin resistance surrogates was examined with multivariate logistic regression and receiver operating characteristic.

RESULTS

A total of 4,352 participants were included, including 93 (2.1%) patients with hyperuricemia alone, 2,875 (66.1%) with hypertension alone and 587 (13.5%) with hypertension plus hyperuricemia. Mutivariate logistic regression showed that TyG index, TyG-BMI, TG/HDL-C and METS-IR were all significantly correlated with hyperuricemia, hypertension and hypertension plus hyperuricemia. Compared with the lowest quartile, the odds ratios (OR) of the highest quartile of the four indicators for hypertension plus hyperuricemia were TyG index: OR 6.39 (95% confidence interval [CI] 4.17-9.78); TyG-BMI: OR 8.54 (95% CI 5.58-13.09); TG/HDL-C: OR 7.21 (95% CI 4.72-11.01); METS-IR: OR 9.30 (95% CI 6.00-14.43), respectively. TyG-BMI and METS-IR had moderate discriminative abilities for hypertension plus hyperuricemia and the AUC values were 0.72 (95% CI 0.70-0.74) and 0.73 (95% CI 0.70-0.75).

CONCLUSIONS

The present study suggested that TyG index, TyG-BMI, TG/HDL-C and METS-IR had a significant correlation with hypertension plus hyperuricemia, and TyG-BMI and METS-IR had discriminative abilities for hypertension plus hyperuricemia.

Hyperuricaemia and gout in cardiovascular, metabolic and kidney disease

During the last century, there has been an increasing prevalence of hyperuricaemia noted in many populations. While uric acid is usually discussed in the context of gout, hyperuricaemia is also associated with hypertension, chronic kidney disease, hypertriglyceridaemia, obesity, atherosclerotic heart disease, metabolic syndrome, and type 2 diabetes. Here we review the connection between hyperuricaemia and cardiovascular, kidney and metabolic diseases. Contrary to the popular view that uric acid is an inert metabolite of purine metabolism, recent studies suggest serum uric acid may have a variety of pro-inflammatory, pro-oxidative and vasoconstrictive actions that may contribute to cardiometabolic diseases. Hyperuricaemia is a predictive factor for the development of hypertension, metabolic syndrome, type 2 diabetes, coronary artery disease, left ventricular hypertrophy, atrial fibrillation, myocardial infarction, stroke, heart failure and chronic kidney disease. Treatment with uric acid-lowering therapies has also been found to improve outcomes in patients with hypertension and kidney disease, in some but not all studies. In conclusion, uric acid is emerging as a potentially treatable risk factor for cardiometabolic diseases, and more clinical trials investigating the potential benefit of lowering serum uric acid are recommended in individuals with hyperuricaemia with and without deposition and concomitant hypertension, metabolic syndrome or chronic kidney disease.

Cardiovascular safety risks associated with gout treatments

INTRODUCTION

Uric acid is the final byproduct of purine metabolism. The loss of the enzyme that hydrolyzes uric acid to allantoin was lost, leading to a decrease in uric acid excretion and its further accumulation. The buildup of uric acid leads to damage in different organ systems, including the cardiovascular system. With the increasing burden of cardiovascular disease worldwide, a growing body of evidence has addressed the relationship between urate, cardiovascular outcomes, and gout medication cardiovascular safety. Areas covered: We discuss the most common gout therapies used for the reduction of serum urate and management of gout flares in different observational and clinical trials and their effects on different aspects of cardiovascular disease. We selected the most representative clinical studies that evaluated cardiovascular outcomes with each gout therapy as well as recommendation given by the most representative guidelines from Rheumatology societies for the management of gout.

EXPERT OPINION

The treatment of gout reduces joint damage and it can also lessen CV morbidity. Allopurinol shows CV safety profile when compared to other ULTs. Evidence supporting CV safety with the use of colchicine and IL-1 agents is promising and research needs to be conducted to further assess this outcome.

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.

A pilot study on the epidemiology of hyperuricemia in Chinese adult population based on big data from Electronic Medical Records 2014 to 2018

BACKGROUND

We performed this study based on big data from Electronic Medical Records (EMR) of outpatients and inpatients from 52 hospitals in China to investigate the prevalence of hyperuricemia in Chinese adults.

METHODS

In this retrospective, descriptive study, a total of 3,363,016 subjects from 52 hospitals in 13 provinces and municipalities in China were enrolled. Eligible subjects were 18 years and older performing serum uric acid test between 2014 and 2018. Subjects were divided into the total group (including the subjects from all the clinic departments) and department-amended group (including the subjects from all the departments except endocrinology, orthopedics, and rheumatology and immunology departments).

RESULTS

The prevalence of hyperuricemia in the department-amended group was lower than that in the total group (23.06% and 23.42% in 2018, respectively; P<0.0001). From 2014 to 2017, the prevalence of hyperuricemia increased year by year (18.29%, 20.02%, 20.16% and 23.06%, respectively) in the department-amended group. Besides, the prevalence of hyperuricemia was higher in men than that in women (38.00% and 11.89%, respectively; P<0.0001) and higher in southern region than in northern region (25.84% and 9.79%, respectively; P<0.0001) in department-amended group in 2018.

CONCLUSIONS

Projections from our study estimate that about 271 million Chinese adults aged 18 years and older may have had hyperuricemia in 2018. These findings will be useful for the future researches and healthcare decision.

Potential benefits of garlic and other dietary supplements for the management of hypertension

Elevated blood pressure is a major risk factor for cardiovascular diseases. Although some effective drug treatments are available, a relatively large proportion of patients have uncontrolled blood pressure. Dietary supplements are used for the prevention and treatment of hypertension as complementary and alternative medicines. Of the various dietary supplements, antioxidants, fish oil and diverse herbal products are commonly used. Within this context, it is important to determine the actual effectiveness and possible side-effects of these supplements; however, some of the products have been poorly investigated for their effects and safety. In the current review, we focus on garlic and several other dietary supplements, such as coenzyme Q10, fish oil and probiotics, that have exhibited significant beneficial effects on blood pressure in clinical trials. In addition, we discuss the possible mechanisms of action responsible for their anti-hypertensive effects, as well as the safety, active ingredients and their potential use as adjunct therapies for uncontrolled hypertension.

Relationship between oxidative stress and inflammation in hyperuricemia: Analysis based on asymptomatic young patients with primary hyperuricemia

The average age of hyperuricemia patients has gradually decreased, but young patients with primary hyperuricemia often do not exhibit clinical symptoms and have not received sufficient attention. However, a lack of symptoms with primary hyperuricemia does not mean that high serum uric acid (UA) levels cannot lead to pathological effects, such as oxidative stress and inflammation, and the specific damage is still unclear. We aimed to determine the relationship between oxidative stress and inflammation to explore the possible role of pathological damage in asymptomatic young patients with primary hyperuricemia.A total of 333 participants were enrolled in our study: 158 asymptomatic young patients with primary hyperuricemia and 175 healthy persons from a health check-up population. Malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and general biochemical markers were measured.We found no differences in biochemical markers (fasting glucose, TG, TC, LDL-C, HDL-C, SCr, BUN, AST, and ALT) between the patients and healthy persons. Subsequent analyses of oxidative stress and inflammation revealed that the serum levels of MDA, IL-6, and TNF-α in the patients were significantly higher than those in the healthy control group (P < .001), and the SOD activity was significantly lower (P < .001). As the UA levels increased, MDA increased significantly and SOD decreased significantly; likewise, IL-6 and TNF-α increased significantly as the UA level increased. MDA showed a significant positive correlation with IL-6 (r = 0.367, P < .001) and TNF-α (r = 0.319, P < .001), and SOD was negatively correlated with IL-6 (r = -0.241, P < .01) and TNF-α (r = -0.308, P < .001). Multivariable logistic regression analysis showed that UA (OR: 2.379, 95% CI: 1.698-3.286, P < .001; OR: 3.261, 95% CI: 1.729-3.857, P < .001; for IL-6 and TNF-α, respectively) and MDA (OR: 1.836, 95% CI: 1.283-2.517, P < .01; OR: 2.532, 95% CI: 1.693-3.102, P < .001; for IL-6 and TNF-α, respectively) were risk factors for high IL-6 and TNF-α and that SOD (OR: 0.517, 95% CI: 0.428-0.763, P < .01; OR: 0.603, 95% CI: 0.415-0.699, P < .001; for IL-6 and TNF-α, respectively) was a protective factor.In our study, some abnormal pathological effects were found in asymptomatic young patients with hyperuricemia, suggesting that in young hyperuricemia patients, oxidative stress, inflammation and the inflammatory response may be related to the oxidative stress induced by UA. Therefore, we should pay more attention to the pathological damage caused by these alterations.

Effects of serum uric acid on blood-pressure lowering treatment

If hyperuricemia is an independent risk factor in blood-pressure control, urate-lowering therapy should be used to reduce cardiovascular risk. It may also act as a prognostic marker of other abnormalities. This review presents current evidence on the relationship between hyperuricemia and hypertension.

Uric acid in the pathogenesis of metabolic, renal, and cardiovascular diseases: A review

The association between uric acid (UA) on one side and systemic hypertension (Htn), dyslipidemia, glucose intolerance, overweight, fatty liver, renal disease and cardiovascular disease (CVD) on the other side is well recognized. However, the causal relationship between UA and these different clinical problems is still debatable. The recent years have witnessed hundreds of experimental and clinical trials that favored the opinion that UA is a probable player in the pathogenesis of these disease entities. These studies disclosed the strong association between hyperuricemia and metabolic syndrome (MS), obesity, Htn, type 2 diabetes mellitus (DM), non-alcoholic fatty liver disease, hypertriglyceridemia, acute kidney injury, chronic kidney disease (CKD), coronary heart disease (CHD), heart failure and increased mortality among cardiac and CKD patients. The association between UA and nephrolithiasis or preeclampsia is a non-debatable association. Recent experimental trials have disclosed different changes in enzyme activities induced by UA. Nitric oxide (NO) synthase, adenosine monophosphate kinase (AMPK), adenosine monophosphate dehydrogenase (AMPD), and nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase are affected by UA. These changes in enzymatic activities can lead to the observed biochemical and pathological changes associated with UA. The recent experimental, clinical, interventional, and epidemiologic trials favor the concept of a causative role of UA in the pathogenesis of MS, renal, and CVDs.

Erratum: Hyperuricemia and uncontrolled hypertension in treated hypertensive patients K-MetS Study: Erratum

[This corrects the article DOI: 10.1097/MD.0000000000004177.].