The association between serum uric acid level and long-term incidence of hypertension: Population-based cohort study

Relationship between serum uric acid, nocturnal hypertension and risk for preeclampsia in high-risk pregnancies

To analyze the possible association between serum uric acid (SUA) and nocturnal hypertension and to evaluate the ability of these variables (alone or in combination) to predict preeclampsia (PE) we conducted a historical cohort study in 532 high-risk pregnancies. Women were divided according to SUA values and nocturnal blood pressure (BP) into four groups: 1- normal SUA and nocturnal normotension; 2- high SUA and nocturnal normotension; 3- normal SUA and nocturnal hypertension and 4- high SUA and nocturnal hypertension. High SUA was defined by the top quartile values and nocturnal hypertension as BP ≥ 120/70 mmHg, using ambulatory blood pressure monitoring (ABPM), during nocturnal rest. Risks for PE were compared using logistic regression. SUA had a weak but significant correlation with daytime systolic ABPM (r = 0.11, p = 0.014), daytime diastolic ABPM (r = 0.13, p = 0.004), nighttime systolic ABPM (r = 0.16, p < 0.001) and nighttime diastolic ABPM (r = 0.18, p < 0.001). Also, all ABPM values were higher in women with high SUA. The absolute risk of PE increased through groups: 6.5%, 13.1%, 31.2%, and 47.9% for groups 1, 2, 3, and 4, respectively, p < 0.001. Compared with Group 1, Group 3 (OR 6.29 95%CI 3.41-11.60), but not Group 2 (OR 2.15 95%CI 0.88-5.24), had statistically significant higher risk for PE. Group 4 (women with both, high SUA and nocturnal hypertension) had the highest risk (OR 13.11 95%CI 6.69-25.70). Risks remained statistically significant after the adjustment for relevant variables. In conclusion, the combination of SUA > 4 mg/dL and nocturnal BP > 120/70 mmHg implies a very high risk to developed PE.

Efficacy and Safety of Allopurinol on Chronic Kidney Disease Progression: A Systematic Review and Meta-Analysis

OBJECTIVE

Hyperuricemia is associated with the progression of chronic kidney disease (CKD). Whether urate-lowering treatment with allopurinol can delay disease progression remains controversial.

METHODS

Relevant databases were searched. Randomized clinical trials comparing the efficacy and -safety of allopurinol in patients with CKD were selected. The primary outcomes were changes in serum uric acid concentration and estimated glomerular filtration rate (eGFR). Random-effects modeling was used to -calculate the standard mean difference (SMD) with 95% CIs.

RESULTS

Four trials enrolling 698 participants were included. All were 2-arm parallel trials with a mean duration follow-up of 22.5 months. Congenital anomalies of the kidney and urinary tract were the most common cause of CKD in children, whereas diabetes was the leading cause of CKD in adults. Allopurinol significantly increased the eGFR compared with control groups (SMD, 2.04; 95% CI, 0.60-3.49; p = 0.005; I2 = 98.23%). Allopurinol led to a significant decrease in serum uric acid concentration compared with the control group (SMD, -5.16; 95% CI, -8.31 to -2.01; p = 0.001; I2 = 98.80%). No significant difference in adverse effects was identified between treatment and control groups.

CONCLUSIONS

Allopurinol treatment in patients with CKD and hyperuricemia slows the decline in eGFR as compared with placebo, without risk of increased adverse effects.

Correlation between hyperuricemia and thickened left ventricular wall in hypertensive young adults

BACKGROUND

In this study, we examine the association between the hyperuricemia(HU) and hypertension(HTN) in Chinese young adults. Besides, the correlation between the occurrence of thickened left ventricular wall and HU was identified in patients with HTN.

METHODS

In all, 360 patients with HTN and 1991 young adults with normal blood pressure(NBP) were enrolled in the study. Participant characteristics were collected. Univariable and multivariable logistic regression tests were utilized to identify the correlation between the presence of HU and HTN, and the correlation between the occurrence of thickened ventricular septum and HU in patients with HTN.

RESULTS

The prevalence of HU in Chinese young adults with HTN was significantly higher than young adults with NBP(36.39% vs. 16.93%). Univariable analyses revealed that 8 factors were related with the presence of HTN with p value < 0.001, including HU, male, body mass index(BMI) ≥ 24 kg/m2, total cholesterol(TC) > 5.17mmol/L, triglyceride(TG) > 1.70mmol/L, high density lipoprotein cholesterol(HDL-C) < 1.0mmol/L, fasting blood glucose(FBG) > 6.10mmol/L and fatty liver. After adjusting these covariates, multivariable analysis revealed that HU[odds ratio(OR):1.47, 95% confidence interval(CI): 1.10-1.95, p = 0.008] remained independent association with HTN in young adults. Additionally, univariable and multivariable logistic analyses revealed that HU kept the independent effect on the presence of thickened interventricular septum(adjusted OR = 1.81, 95% CI: 1.05-3.11, P = 0.03) and thickened left ventricular posterior wall(adjusted OR = 2.28, 95% CI: 1.28-4.08, P = 0.005) in young adults with HTN.

CONCLUSION

HU was independently associated with HTN in young adults. HU was independently correlated with thickened left ventricular wall, including interventricular septum and left ventricular posterior wall, in young adults with HTN.

Thyroid function, renal function, and depression: an association study

Objective

To investigate the correlations between thyroid function, renal function, and depression.

Methods

Clinical data of 67 patients with Major depressive disorder (MDD) and 36 healthy control subjects between 2018 and 2021 were collected to compare thyroid and renal function. Thyroid and renal functions of depressed patients were then correlated with the Hamilton Depression Rating Scale (HAMD) and the Hamilton Anxiety Rating Scale (HAMA).Spearman correlation analysis was used to find the correlation between renal function, thyroid function, and depression. A logistic regression was performed to find significant predictors of depression.

Results

Triiodothyronine protamine (T3), thyroxine (T4), free triiodothyronine protamine (FT3), uric acid, sodium, and anion gap were lower in the MDD group than in the control group (p < 0.05). Correlation analysis of thyroid function, renal function, and factor terms of HAMD in the MDD group suggested that diurnal variation, hopelessness, and depression level were positively correlated with thyrotropin (TSH) (p < 0.05). Cognitive disturbance, retardation, and depression level were negatively correlated with creatinine (p < 0.05). Diurnal variation was negatively correlated with sodium ion (p < 0.01); hopelessness and depression level were positively correlated with chloride ion (p < 0.05); diurnal variation, retardation, and depression level were negatively correlated with anion gap (p < 0.05). Diurnal variation (p < 0.01) and retardation (p < 0.05) were negatively correlated with osmolality. Cognitive disturbance and depression level were positively correlated with estimated glomerular filtration rate (eGFR) (p < 0.05). In the MDD group, correlation analysis of thyroid function, renal function, and HAMA factor terms suggested that the total HAMA score and anxiety level were positively correlated with chloride ion (p < 0.05); psychic anxiety, total HAMA score, and anxiety level were negatively correlated with anion gap (p < 0.05). Furthermore, a low level of anion gap was an independent risk factor for depression and anxiety levels (p < 0.05).

Conclusion

Low thyroid function and reduced waste metabolized by the kidneys in patients with MDD suggest a low intake and low metabolism in depressed patients. In addition, subtle fluctuations in the anion gap in depressed patients were strongly correlated with the degree of depression and anxiety.

Association between hyperuricemia and hypertension and the mediatory role of obesity: a large cohort study in China

OBJECTIVE

This study aimed to investigate the sex-specific association between hyperuricemia and the risk of hypertension and whether obesity mediates this association.

METHODS

This study included 31,395 (47.0% women) adults without hypertension, cardiovascular disease, or cancer at baseline who completed at least one follow-up annual examination between 2009 and 2016. Cox regression models were performed to calculate hazard ratios and 95% confidence intervals. Mediation analysis was conducted to estimate the effect of body mass index on the association between hyperuricemia and hypertension.

RESULTS

During a median 2.9-year follow-up, hyperuricemia was significantly associated with a higher risk of hypertension (HR 1.15, 95%CI 1.07-1.24 for all participants; HR 1.12, 95%CI 1.03-1.22 for men; and HR 1.23, 95%CI 1.02-1.48 for women) after adjustment for potential confounders. Additional adjustment for body mass index attenuated this association (HR 1.09, 95%CI 1.08-1.10 for all participants; HR 1.07; 95%CI 0.98-1.16 for men; HR 1.18; 95%CI 0.96-1.44 for women). Mediation analysis showed that BMI partially mediated the relationship between hyperuricemia and incident hypertension (indirect effect HR 1.09, 95%CI 1.08-1.10; direct effect: HR 1.08, 95%CI 1.02-1.15). The percentage of the mediation effect was 53.2% (95%CI 37.9-84.5).

CONCLUSION

Hyperuricemia is associated with a risk of hypertension in both sexes, and BMI partially mediates hyperuricemia-related incident hypertension.

Association of serum uric acid with the risk of developing hypertension: A prospective cohort study with mediation analysis

Elevated serum uric acid (SUA) is associated with the incidence of hypertension, but whether relevant metabolic factors have mediating effects is not certain. Our study was based on a functional community cohort established in Beijing. In 2015, a total of 7482 individuals without hypertension were recruited and followed up until 2019. Multivariate logistic regression analysis was used to investigate the association between SUA and hypertension. Cross-lagged panel analysis and mediation analysis were used to explore the effects of metabolic factors on the association between SUA and incident hypertension. During the average 4-year follow-up, the cumulative incidence of hypertension was 10.9% (n = 580). SUA was an independent risk factor for hypertension, and the RRs (95% CI) for subjects with baseline SUA levels in quartile 2, quartile 3 and quartile 4 were 1.20 (0.88-1.63), 1.50 (1.10-2.05), and 1.57 (1.11-2.22) compared to those in quartile 1, respectively. The cross-lagged panel analysis showed that the increases in Cr, TG, LDL, ALT, AST and WBC occurred after SUA increased (P < 0.001). Among these factors, TG, WBC and ALT played an intermediary role in both men (TG: 14.76%; WBC: 11.61%; ALT: 15.93%) and women (TG: 14.55%; WBC: 8.55%; ALT: 6.89%). The elevated SUA concentration was an independent risk factor for hypertension in the Chinese population, and TG, WBC and ALT had important mediating effects on the association between SUA and hypertension.

Association between dyslipidaemia and the risk of hyperuricaemia: a six-year longitudinal cohort study of elderly individuals in China

BACKGROUND

Despite abundant evidence linking dyslipidaemia to an increased risk of hyperuricaemia, the exact association between each component of dyslipidaemia and hyperuricaemia remains controversial. Thus, the objective of this research was to examine the correlation between dyslipidaemia and its components, as well as hyperuricaemia in Chinese people over the age of 60.

METHODS

In this study, 4018 participants over 60 years without hyperuricaemia were investigated from 2014 to 2020. The association between each dyslipidaemia component and hyperuricaemia was evaluated employing Cox proportional hazards models. This research conducted further stratified and sensitivity analyses to assess the potential relationship.

RESULTS

A total of 1155 participants suffered from hyperuricaemia (28.75%) at the time of the 6-year follow-up survey. In multivariable-adjusted analyses, compared to participants with normal lipid levels, those with dyslipidaemia had 1.28 times the risk (95% confidence interval 1.12 to 1.47) of experiencing hyperuricaemia. The hazard ratios (HR) (95% CI) comparing high TC, high TG, high LDL-C, and low HDL-C of dyslipidaemia with the regular group were 0.99 (0.72 to 1.37), 1.30 (1.07 to 1.57), 1.02 (0.70 to 1.50), and 1.20 (1.00 to 1.44), respectively. There was a nonlinear dose-response between TG, HDL-C, and serum uric acid (SUA).

CONCLUSIONS

Dyslipidaemia and its two distinct types, high TG and low HDL-C, increased hyperuricaemia incidence in this prospective cohort. Further research should be undertaken to investigate the possible reverse causality between different components of dyslipidaemia and hyperuricaemia.

SGLT2 Inhibitors: New Hope for the Treatment of Acute Myocardial Infarction?

Among all of the new antidiabetic drugs, an increasing number of studies have evaluated the relationship between the sodium-glucose cotransporter 2 inhibitors (SGLT2i) and acute myocardial infarction (AMI). Since SGLT2i like empagliflozin, canagliflozin, and recently, dapagliflozin have shown impressive positive effects in patients with chronic heart failure with reduced ejection fraction (HFrEF), it has increased research interest to explore the cardiac molecular mechanisms underlying the clinical benefits and attracted more attention to the effects of SGLT2i on a series of cardiovascular events. Experimental and clinical data on SGLT2i treatment after AMI is limited. This is a review of the clinical and preclinical effects of SGLT2i, focusing on available data on the effects of SGLT2i in AMI patients with a brief overview of ongoing trials.

Health risk assessment of exposure to organochlorine pesticides in the general population in Seoul, Korea over 12 years: A cross-sectional epidemiological study

This study evaluated the 12-year trends in serum levels of 28 organochlorine pesticides (OCPs) in 880 adults living in Seoul, Korea. The OCP levels decreased from 2006 to 2017, and p,p'-dichlorodiphenyldichloroethylene was a predominant compound. OCP levels were higher in females than in males, and showed positive associations with BMI and age. The OCP concentrations had inverted U-shaped associations with low-density lipoprotein cholesterol and total cholesterol. Concentrations of β-hexachlorocyclohexane were significantly higher in patients with hypertension than in participants that were normotensive. OCP levels showed positive associations with uric acid, creatinine, and thyroid-stimulating hormone, but negative associations with free thyroxine. Participants with diabetes had significantly higher OCP levels than those without it. Principal component analysis suggested possible differences in disease manifestation depending on the composition of OCPs. These results suggest that OCPs might disturb renal transport and thyroid homeostasis. To our knowledge, the inverted U-shaped associations of heptachlor epoxide and endosulfan with cholesterol, the epidemiological associations of trans-nonachlor and endosulfan with thyroid hormones, and the association of p,p'-DDE with hyperuricemia have not been previously reported in general population. This is the first long-term study to show trends of 28 OCPs in serum and associations with various health indicators in Korea.

Uric Acid, Hypertensive Phenotypes, and Organ Damage: Data from the Pamela Study

Purpose of Review

To examine published and unpublished data collected in the context of the Pressioni Arteriose Monitorate E Loro Associazioni (PAMELA) study on the relationships between serum uric acid (SUA), office and out-of-office blood pressure (BP), and organ damage.

Recent Findings

SUA values were directly and significantly related to a large number of covariates that participate at cardiovascular risk determination, such as blood glucose, total serum cholesterol, serum triglycerides, body mass index, and serum creatinine. Additional variables included echocardiographically-determined left ventricular mass index and BP values, the latter not just when measured in the office but also when evaluated at home or over the 24-h period. White-coat hypertension and masked hypertension were characterized, as sustained hypertension, by a significant increase in SUA levels, which were also directly related to different indices of 24-h BP variability. No substantial difference in SUA levels was found when data were analyzed according to the dipping or non-dipping nocturnal BP profile.

Summary

Data collected in the frame of the PAMELA study document the presence of a close relationship between SUA levels and BP values independently on the hypertensive phenotype patterns of BP increase (office, 24 h, or both) and nighttime BP profile. They also document the increase in SUA as a potential factor favoring the occurrence of new hypertension and new left ventricular hypertrophy.

Hyperuricemia as a prognostic marker for long-term outcomes in patients with myocardial infarction with nonobstructive coronary arteries

Background

Hyperuricemia (HUA) has been proved as a predictor of worse outcomes in patients with coronary artery disease. Here, we investigated the prognostic value of HUA in a distinct population with myocardial infarction with nonobstructive coronary arteries (MINOCA).

Methods

A total of 1179 MINOCA patients were enrolled and divided into HUA and non-HUA groups. HUA was defined as a serum uric acid level ≥ 420 μmol/L in men or ≥ 357 μmol/L in women. The primary study endpoint was a composite of major adverse cardiovascular events (MACE), including all-cause death, nonfatal MI, nonfatal stroke, revascularization, and hospitalization for unstable angina or heart failure. Kaplan–Meier, Cox regression, and receiver-operating characteristic analyses were performed.

Results

Patients with HUA (prevalence of 23.5%) had a significantly higher incidence of MACE (18.7% vs. 12.8%; p = 0.015) than patients without during the median follow-up of 41.7 months. HUA was closely associated with an increased risk of MACE even after multivariable adjustment (hazard ratio 1.498, 95% confidence interval: 1.080 to 2.077; p = 0.016). HUA remained a robust risk factor of MACE after propensity score matching analysis. Moreover, HUA showed an area under the curve (AUC) of 0.59 for predicting MACE. Incorporation of HUA to the thrombolysis in myocardial infarction (TIMI) score yielded a significant improvement in discrimination for MACE.

Conclusions

HUA was independently associated with poor prognosis after MINOCA. Routine assessment of HUA may facilitate risk stratification in this specific population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-021-00636-2.

The Association between the Serum Uric Acid Level and Hypertension in Middle-Aged and Elderly Adults

Background

Studies on serum uric acid (sUA) levels and hypertension (HTN) are controversial. To investigate the association between the sUA level and the incident of HTN in middle-aged and elderly adults, we performed this study.

Methods

6399 participants aged ≥40 years from the National Health and Nutrition Examination Survey (NHANES) were included. Weighted multiple logistic regression analysis was carried out to evaluate the relationship between the sUA level and the incident of HTN, exploring the potential nonlinear relationship using the fitted smoothing curves. If nonlinearity was observed, the inflection point was further calculated by a recursive algorithm.

Results

A positive relationship between the sUA level and the incident of HTN was found. However, it may differ in different race groups, nor between male and female. Moreover, the association between the sUA level and the incident of HTN followed a U-shaped curve in male (turning point: sUA 4.1 mg/dL) and Whites (turning point: sUA 7.9 mg/dL).

Conclusions

The results revealed that the sUA level is positively correlated with the incident of HTN, in middle-aged and elderly adults. However, it followed a U-shaped curve in males and Whites.

Association between Serum Uric Acid and Hypertension in Han and Yugur of Gansu Province: The China National Health Survey

INTRODUCTION

Serum uric acid (SUA) has been found correlated with an increased risk of hypertension, but evidence is sparse regarding the association in Gansu Province, especially in Yugur people. This study aimed to explore the nonlinear relationship between SUA levels and hypertension in Han and Yugur people in China.

METHODS

The cross-sectional study samples (n = 5,327) were from the China National Health Survey (CNHS) in Gansu Province. Participants were selected using a multistage stratified cluster sampling method. SUA was measured by enzymatic methods. The restricted cubic spline regression was performed to evaluate the shape of the association.

RESULTS

The overall prevalence of hypertension and hyperuricemia was 28.4% and 17.0%, respectively, in this study. Comparing the highest (>416.4 μmol/L) to the lowest (<254.1 μmol/L) SUA level groups, the multivariable adjusted differences and 95% confidence intervals (CIs) in blood pressure (BP) were 6.15 (4.22, 8.08) mm Hg and 4.87 (3.51, 6.23) mm Hg for SBP and DBP in Han, and 2.22 (-0.73, 5.18) mm Hg and 2.56 (0.38, 4.75) mm Hg for SBP and DBP in Yugur people, respectively. The corresponding odds ratios (95% CIs) for hypertension were 3.16 (2.26, 4.43) and 2.37 (1.46, 3.89) in Han and Yugur people, respectively. The restricted cubic spline regression models illustrated that both BP level and the risk of hypertension increased with elevated SUA levels in Han and Yugur people.

CONCLUSIONS

SUA was significantly and independently associated with an increased risk of hypertension in Han and Yugur people. Prospective studies are needed to confirm these findings.

Dose-response association between serum uric acid levels and incident hypertension: a systematic review and meta-analysis of 17 prospective cohort studies of 32 thousand participants

BACKGROUND

Various magnitudes of the risk of incident hypertension (IHTN) have been reported to be associated with increased serum uric acid (SUA) levels in observational studies, however, whether a dose-response relation exists is unclear. We aimed to quantitatively evaluate the SUA-IHTN association.

METHODS

We searched the PubMed and Embase databases for relevant articles published prior to 21 October 2019. Random-effects models were used to estimate the summary relative risks (RRs) and 95% confidence intervals (CIs) of the IHTN risk in relation to SUA levels. We used restricted cubic splines to model the dose-response association between SUA levels and IHTN.

RESULTS

A total of 17 articles (17 prospective cohort studies) including 321,716 adults and 65,890 IHTN cases were identified. The pooled RR was 1.10 (95% CI 1.07-1.13; I²=90.7%; n = 17) per 1 mg/dL change in the SUA level. In addition, we found evidence of a linear and positive dose-response association between SUA levels and IHTN (P_{non-linearity} = 0.069). The results of the subgroup and sensitivity analyses were consistent with those of the primary analysis.

CONCLUSION

These data suggested that people with higher SUA levels had a higher IHTN risk. SUA levels need to be controlled to reduce or eliminate the risk of IHTN associated with SUA levels. Clinical trial studies or diagnostic studies are needed to determine the optimal cut-off point for SUA.

Uric acid can enhance MAPK pathway-mediated proliferation in rat primary vascular smooth muscle cells via controlling of mitochondria and caspase-dependent cell death

Hyperuricemia may be a risk factor for cardiovascular diseases such as hypertension and atherosclerosis, but the mechanisms underlying uric acid-induced pathological conditions remain unknown. In this study, we investigated the effect of short time and long-term administration of increasing uric acid concentrations on cell viability, proliferative and apoptotic pathways in vascular smooth muscle cells (VSMCs). Cell viability/proliferation was determined with WST-1 assay. Expression levels of mitogen-activated protein kinases (MAPKs) (phosphorylated (p)-p38 and p-p44/42 MAPK), extrinsic (caspase 3, caspase 8), and intrinsic (B-cell lymphoma-extra-large (Bcl-xL)) apoptotic pathway proteins were measured by Western blotting. In order to assess the proliferative effects of uric acid incubations on VSMCs, we monitored the proliferative/apoptosis signaling pathways for up to 24 h. Our results indicated that uric acid increases cell viability at time and dose-dependently in VSMCs. Immunoblotting results showed that uric acid treatment elevated the expression level of p-p38 MAPK but did markedly reduce the protein levels of p-p44/42, compared with all the uric acid doses-treated VSMCs, especially at 1 h. Uric acid stimulation increased caspase-3 protein levels and decreased Bcl-xL, but did not alter caspase-8 protein expression at the same dose and time. Furthermore, low uric acid incubations (0-7.5 mg/dL) did not affect any signaling pathways for long time points (6-24 h). In conclusion, our study demonstrates for the first time that VSMCs induced with uric acid can affect cell viability, proliferative, and apoptosis pathways at the widest time and dose range. These findings provide a better understanding of the uric acid effects related to vascular impairments.

Uric Acid and Hypertension: Prognostic Role and Guide for Treatment

The relationship between serum uric acid (SUA) and hypertension has been a subject of increasing interest since the 1870 discovery by Frederick Akbar Mahomed. Several epidemiological studies have shown a strong association between high SUA levels and the presence or the development of hypertension. Genetic analyses have found that xanthine oxidoreductase (XOR) genetic polymorphisms are associated with hypertension. However, genetic studies on urate transporters and Mendelian randomization studies failed to demonstrate a causal relationship between SUA and hypertension. Results from clinical trials on the role of urate-lowering therapy in the management of patients with hypertension are not uniform. Our study sought to analyze the prognostic and therapeutic role of SUA in the hypertensive disease, from uric acid (UA) biology to clinical trials on urate-lowering therapies.

[Asymptomatic Hyperuricemia and Risk Of Cardiovascular and Renal Diseases]

Asymptomatic hyperuricemia (HU) is common in the population and significantly contributes to the general cardiovascular risk. Despite extensive study of this condition there is still no conclusive answers to questions about detection of asymptomatic HU and its effect on the risk for development and progression of cardiovascular and kidney diseases. This review summarizes key information about these issues, which has been accumulated by the present time.

High serum uric acid within the normal range is a useful predictor of hypertension among Japanese community-dwelling elderly women

Background

The risk associated with serum uric acid (SUA) levels when within the normal range is unknown. This study aims to examine whether SUA within the normal range is a predictor of hypertension.

Methods

The subjects comprised 704 men aged 71 ± 9 (mean ± standard deviation) years and 946 women aged 70 ± 8 years recruited for a survey at the community based annual medical check-up. The main outcome was the presence of hypertension (antihypertensive medication and/or having SBP ≥140 mmHg and/or DBP ≥90 mmHg).

Results

At baseline, 467 (66.3%) men and 608 (64.3%) women had hypertension. Comparing to lowest quartile in women (SUA-1, uric acid < 4.1 mg/dL), the unadjusted odds ratios (ORs) [95% confidence interval (CI)] for hypertension of SUA-2 (4.1 to 4.7 mg/dL), SUA-3 (4.8 to 5.4 mg/dL), and SUA-4 (≥5.5 mg/dL) were 1.11 (0.78–1.59), 1.75 (1.20–2.55), and 1.89 (1.30–2.77), respectively. These associations were apparent even after adjustments for age, but ORs were attenuated after adjusting for all confounding factors. During a follow-up of 3.0 years, there were 35 (24.0%) hypertension cases in men and 51 (20.8%) in women. In women only, a significant association between increased SUA categories and incidence of hypertension was observed, and the multivariate-ORs (95% (CI) for incident hypertension of SUA-3 (4.5–5.2 mg/dL) and SUA-4 (≥5.3 mg/dL) were 2.23 (0.81–6.11) and 3.84 (1.36–10.8), respectively.

Conclusions

These results suggest that baseline SUA within the normal range could be an important predictor for incidence of hypertension in Japanese community-dwelling elderly women.

Association between the uric acid and hypertension in community-based Chinese population: stratified analysis based on body mass index and age

Many studies have shown that uric acid was related to hypertension. However, the association dependence on body mass index (BMI) or age was unclear. This study was performed with a group of 4012 Chinese population aged 30 to 92 years old. Subjects were divided into four groups according to the quartiles of uric acid (UA) concentration [First group: ≤ 231 μmol/L (reference), Second group: 231-289 μmol/L, Third group: 289-362 μmol/L, Fourth group: > 362 μmol/L]. Hypertension was defined as newly measured blood pressure ≥ 140/90 mmHg or taking antihypertensive drugs. Stratified analysis based on BMI (< 28 kg/m² vs ≥ 28 kg/m²) and age (< 60 years old vs ≥ 60 years old) to analyze the association between UA and hypertension. Subjects were 54.50 (45.00, 63.00) years old, and 40.98% were male, 38.33% were hypertension. Adjusted odds ratios (95% confidence intervals) for the association of UA and hypertension were 2.226 (1.662, 2.980), 4.340 (3.253, 5.790), 5.898 (4.434, 7.845) and 6.557 (4.927, 8.727) in the four groups among ≥ 60 years old respectively comparing with first group among < 60 years old. Adjusted odds ratios (95% confidence intervals) for the association between UA and hypertension were 2.170 (1.236, 3.808), 5.260 (3.267, 8.468), 9.056 (5.509, 14.888) and 3.730 (2.529, 5.550) in the four groups among BMI ≥ 28 kg/m² respectively comparing with first group among BMI < 28 kg/m². Uric acid was significantly associated with the hypertension. The association was stronger among subjects ≥ 60 years old or BMI ≥ 28 kg/m².

Uric acid and its correlation with hypertension in postmenopausal women: A multi-ethnic study (Observational study)

We investigate the association of uric acid with hypertension among Han, Uygur, and Kazakh populations in the Xinjiang Province of Western China. Our study aims to evaluate the relationships of serum uric acid (SUA) with hypertension in the Chinese population according to the menopausal status. Medical data of 1684 Han, 1895 Uygur, and 294 Kazakh people was examined. The prevalence of hypertension was calculated by the quartiles of SUA. Correlation between hypertension-related risk factors calculated and compared between men and women. SUA was higher in men than in women. The level was significantly higher in postmenopausal than premenopausal women (4.40 ± 1.75 v.s 4.06 ± 1.63 mg/dl, P < .01). Logistic regression analysis showed Body mass index (BMI) [OR = 1.08, P < .01]; and eGFR<60 vs.≥60 [OR = 1.22, P = .04] were independent risk factors for hypertension in women. Age and diabetes were independent risk factors for the participants with hypertension [OR = 1.04, P < .01] and [OR = 2.24, P < .01]. High quartile SUA group has increased the risk for hypertension in postmenopausal women [OR = 1.34, P = .048]. We found that postmenopausal women have high SUA compared to premenopausal women. The high SUA quartiles uric acid may be an independent risk for hypertension in postmenopausal women.

Higher baseline uric acid concentration is associated with non-attainment of optimal blood pressure

A significant relationship exists between elevated uric acid concentration and both prevalent and incident hypertension; however, data regarding the influence of higher uric acid concentration at baseline on blood pressure control by antihypertensive drugs is scarce. Thus, a prospective cohort study was performed. The study outcome was the non-attainment of optimal blood pressure (NOBP). NOBP level was defined according to the Japanese hypertension guideline. This study enrolled a Japanese community-based cohort (N = 8,664; age 65.5 ± 6.4 years; women, 55.0%) who were not using antihypertensive drugs on the first visit for a health check-up program but started using antihypertensive drug(s) on the next-year visit. The participants were classified into quartiles based basic uric acid concentration. Odds ratios (ORs) were calculated for NOBP as the primary outcome measure. Multivariable logistic analysis showed that quartile 4 was significantly associated with NOBP when quartile 1 was set as the reference (OR (95% confidence interval), 1.36 (1.16-1.59), p<0.01), adjusted for potential confounders, such as age, sex, body mass index, presence of diabetes/dyslipidemia/chronic kidney disease (CKD), history of cardiovascular disease, daily drinking, and current smoking. In the subgroup analysis of female participants and participants with diabetes and CKD, a significant association was observed between +1 mg/dL of uric acid and NOBP. Higher uric acid concentration at baseline was significantly associated with NOBP on the first use of antihypertensive drug(s).

Tubular effects of sodium-glucose cotransporter 2 inhibitors: intended and unintended consequences

PURPOSE OF REVIEW

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are antihyperglycemic drugs that act by inhibiting renal sodium-glucose cotransport. Here we present new insights into 'off target', or indirect, effects of SGLT2 inhibitors.

RECENT FINDINGS

SGLT2 inhibition causes an acute increase in urinary glucose excretion. In addition to lowering blood glucose, there are several other effects that contribute to the overall beneficial renal and cardiovascular effects. Reabsorption of about 66% of sodium is accomplished in the proximal tubule and dependent on the sodium-hydrogen exchanger isoform 3 (NHE3). SGLT2 colocalizes with NHE3, and high glucose levels reduce NHE3 activity. The proximal tubule is also responsible for the majority of phosphate (Pi) reabsorption. SGLT2 inhibition is associated with increases in plasma Pi, fibroblast growth factor 23 and parathyroid hormone levels in nondiabetics and type 2 diabetes mellitus. Studies in humans identified a urate-lowering effect by SGLT2 inhibition which is possibly mediated by urate transporter 1 (URAT1) and/or glucose transporter member 9 in the proximal tubule. Of note, magnesium levels were also found to increase under SGLT2 inhibition, an effect that was preserved in nondiabetic patients with hypomagnesemia.

SUMMARY

Cardiorenal effects of SGLT2 inhibition might involve, in addition to direct effects on glucose homeostasis, effects on NHE3, phosphate, urate, and magnesium homeostasis.

Association between serum uric acid levels and metabolic markers in patients with type 2 diabetes from a community with high diabetes prevalence

BACKGROUND

The importance of uric acid has been increasingly appreciated because of its association with the development of diabetes mellitus and related diseases.

OBJECTIVE

This study was undertaken to evaluate the association of serum uric acid (SUA) level with different clinical and biochemical parameters in patients with type 2 diabetes from Saudi Arabia.

METHODS

Clinical and biochemical data from the patients were obtained and assessed in a cross-sectional design. Relationships between SUA level and various clinical and biochemical parameters were analysed.

RESULTS

SUA level was positively associated with increased incidence of cardiovascular diseases (CVD) in patients with abnormal eGFR (<90 mL/min/1.73 m² ). HbA1c was found to be inversely associated with hyperuricemia in patients with normal eGFR level (≥90 mL/min/1.73 m² ). Incidence of metabolic syndrome did not show any relationship with SUA level. However, the incidence of hypertension, a component of metabolic syndrome, was significantly higher among patients with hyperuricemia. Waist circumference and serum triglycerides were higher, whereas serum high-density lipoprotein level was lower in patients with higher SUA level. Patients with hyperuricemia had higher incidence of CVDs than those of the normouricemic group.

CONCLUSION

SUA level was positively associated with incidence of cardiovascular diseases CVD in patients with abnormal eGFR. HbA1c correlated significantly with SUA level in patients with normal eGFR. Incidence of metabolic syndrome did not show any association with SUA level. Incidence of hypertension, waist circumference and serum triglycerides were significantly higher and serum high-density lipoprotein level was lower in patients with higher SUA level.

Characteristics of the urinary microbiome in kidney stone patients with hypertension

BACKGROUND

Kidney stone disease (KSD) is more common in individuals with hypertension (HTN) than in individuals with normotension (NTN). Urinary dysbiosis is associated with urinary tract disease and systemic diseases. However, the role of the urinary microbiome in KSD complicated with HTN remains unclear.

METHODS

This study investigated the relationship between the pelvis urinary microbiome and blood pressure (BP) in patients with KSD co-occurring with HTN (KSD-HTN) and healthy controls (HC) by conducting 16S rRNA gene sequencing of bacteria in urine samples. The urine samples were collected (after bladder disinfection) from 50 patients with unilateral kidney calcium stones and NTN (n = 12), prehypertension (pHTN; n = 11), or HTN (n = 27), along with 12 HCs.

RESULTS

Principal coordinates analysis showed that there were significant differences in the urinary microbiomes not only between KSD patients and HCs but also between KSD-pHTN or KSD-HTN patients and KSD-NTN patients. Gardnerella dominated in HCs, Staphylococcus dominated in KSD-NTN patients and Sphingomonas dominated in both KSD-pHTN and KSD-HTN patients. The abundance of several genera including Acidovorax, Gardnerella and Lactobacillus was correlated with BP. Adherens junction and nitrogen and nucleotide metabolism pathways, among others, were associated with changes in BP.

CONCLUSIONS

The findings suggest that patients with KSD complicated with HTN have a unique urinary microbiome profile and that changes in the microbiome may reflect disease progression and may be useful to monitor response to treatments.

Serum uric acid a depression biomarker

Objective

We aimed to investigate the difference in serum uric acid(SUA)levels between subtypes of depression and normal population, and whether SUA can be used to identify bipolar disorder depressive episode and major depressive disorder and predict the length of hospital stay.

Methods

1543 depression patients and 1515 healthy controls were obtained according to the entry and exclusion criteria from one mental health center of a tertiary hospital in southwestern China. The diagnosis and classification of depression was in accordance with ICD-10. The SUA value was derived from fasting plasma samples analysis. The level of SUA of all the participants was quantified using Roche cobas8000-c702-MSB automatic biochemical analyzer. Data were analyzed by SPSS18.0 statistical software package.

Results

Overall, the level of SUA in patients with depression was lower than that in normal control. Specifically, males’ SUA levels were in the interval of [240, 323.3) and [323.3, 406.6), and women were in the [160, 233.3] levels. The SUA level of bipolar disorder depressive episode was higher compared to major depressive disorder level. Interestingly, male patients who were hospitalized for two weeks had higher SUA than those who were hospitalized for three weeks or four weeks.

Conclusions

Our results suggest that the length of hospital stay may be associated with SUA, and when it is difficult to make a differential diagnosis of bipolar disorder depressive episode and major depressive disorder, the level of SUA may be considered. The adjustment of SUA as a method for treating depression needs to be carefully assessed.

Association of anti-hyperuricemia treatment and prevalent cardiovascular disease in hypertensive patients

INTRODUCTION

The current study aimed to evaluate the association of anti-hyperuricemia treatment and prevalent cardiovascular disease (CVD) in hypertensive patients.

MATERIAL AND METHODS

Primary hypertensive patients with hyperuricemia were enrolled. All participants were separated into two groups: anti-hyperuricemia and control groups (without anti-hyperuricemia treatment). Comparisons of prevalent CVD including coronary heart disease, ischemic stroke and heart failure were made and the associations of anti-hyperuricemia treatment and prevalent CVD were analyzed.

RESULTS

Compared to the anti-hyperuricemia group, patients in the control group had significantly higher serum C-reactive protein (10.6 ±2.8 vs. 7.4 ±1.2 mg/dl) and uric acid (UA) levels (438 ±33 vs. 379 ±64 µmol/l), and were more likely to receive β-blockers (34.2% vs. 31.1%) and calcium channel blockers (49.2% vs. 43.4%). The prevalence of ischemic stroke was higher in the control group (15.8% vs. 11.3%). Compared to other groups, blood pressure was significantly higher in patients in the 4^th quartile serum UA level group. In the unadjusted model, anti-hyperuricemia treatment was significantly associated with a reduced odds ratio (OR) of composite CVD. After adjusting for potential covariates, OR of anti-hyperuricemia treatment for composite CVD was 0.89 with a 95% confidence interval (IC) of 0.82-0.98. Associations of anti-hyperuricemia treatment and ischemic stroke were also significant with OR = 0.93 and 95% CI: 0.88-0.99, while associations of anti-hyperuricemia with coronary heart disease and heart failure attenuated into insignificance after adjusting for covariates.

CONCLUSIONS

In hypertensive patients with hyperuricemia, anti-hyperuricemia treatment was associated with lower odds of prevalent CVD.

The long-term rapid increase in incidence of adenocarcinoma of the kidney in the USA, especially among younger ages

BACKGROUND

We previously observed a rapid increase in the incidence of renal cell carcinoma (RCC) in men and women between 1935 and 1989 in the USA, using data from the Connecticut Tumor Registry. This increase appeared to be largely explained by a positive cohort effect, but no population-based study has been conducted to comprehensively examine age-period-cohort effects by histologic types for the past decade.

METHODS

We calculated age-adjusted and age-specific incidence rates of the two major kidney-cancer subtypes RCC and renal urothelial carcinoma, and conducted an age-period-cohort analysis of 114 138 incident cases of kidney cancer reported between 1992 and 2014 to the Surveillance, Epidemiology, and End Results programme.

RESULTS

The age-adjusted incidence rates of RCC have been increasing consistently in the USA among both men and women (from 12.18/100 000 in 1992-1994 to 18.35/100 000 in 2010-2014 among men; from 5.77/100 000 in 1992-1994 to 8.63/100 000 in 2010-2014 among women). Incidence rates generally increased in successive birth cohorts, with a continuing increase in rates among the younger age groups (ages 0-54 years) in both men and women and among both Whites and Blacks. These observations were confirmed by age-period-cohort modelling, which suggested an increasing birth-cohort trend for RCC beginning with 1955 birth cohorts, regardless of the assumed value for the period effect for both men and women and for Whites and Blacks.

CONCLUSIONS

Known risk factors for kidney cancer may not fully account for the observed increasing rates or the birth-cohort pattern for RCC, prompting the need for additional etiologic hypotheses (such as environmental exposures) to investigate these descriptive patterns.

Hyperuricemia predicts the risk for developing hypertension independent of alcohol drinking status in men and women: the Saku study

Hyperuricemia has been reported to be a risk factor for hypertension, but this association may be affected by alcohol consumption. This study aimed to investigate whether hyperuricemia remains a risk factor for hypertension after eliminating the effect of alcohol consumption. This study comprised 7848 participants (4247 men and 3601 women) aged 30-74 years without hypertension who had undergone a medical checkup between April 2008 and March 2009 at Saku Central Hospital, Nagano Prefecture, Japan. Hyperuricemia was defined as uric acid >7.0 mg/dl in men, ≥6.0 mg/dl in women, and/or receiving treatment for hyperuricemia or gout. The incidence of hypertension was defined as the first diagnoses of blood pressure ≥140/≥ 90 mmHg and/or initiations of antihypertensive drug treatment. Multivariable-adjusted hazard ratios (HRs) of hyperuricemia for the incidence of hypertension after adjustment for and classification by alcohol consumption were estimated using the Cox proportional hazard model. During a mean of 4.0 years of follow-up, 1679 individuals developed hypertension. After adjustment for alcohol consumption, the HRs (95% confidence interval) associated with hyperuricemia were 1.37 (1.19-1.58) in men and 1.54 (1.14-2.06) in women. Among nondrinkers, the HR was 1.29 (0.94-1.78) in men with hyperuricemia compared with men without, and the corresponding HR was 1.57 (1.11-2.22) in women. The corresponding HR was 1.88 (1.27-2.86) in all participants with baseline blood pressure <120/80 mmHg. The interactions between hyperuricemia and sex (P = 0.534) and between drinking and sex (P = 0.713) were not significant. In conclusion, hyperuricemia predicts the risk for developing hypertension independent of alcohol drinking status.

Hyperuricemia and long-term mortality in patients with acute myocardial infarction undergoing percutaneous coronary intervention

Background

Although serum uric acid (UA) was regarded to be involved in cardiovascular disease, the role of serum UA (SUA) as a risk factor in acute myocardial infarction (AMI) is controversial. We investigated whether hyperuricemia was linked with long-term mortality in patients with AMI who underwent percutaneous coronary intervention (PCI).

Methods

Patients with AMI who received PCI were consecutively included. The definition of preprocedural hyperuricemia was a SUA level >7 mg/dL (417 mmol/L) in males and >6 mg/dL (357 mmol/L) in females. All-cause mortality was assessed during 2.3-year median follow up period.

Results

One thousand and five patients with AMI undergoing PCI were enrolled in a single center study, 307 (30.5%) patients had hyperuricemia. After adjusting for potential confounding factors, the multivariable analysis indicated that preprocedural hyperuricemia was related to an increased risk of all-cause mortality during the 2.3-year follow-up (HR: 1.97; 95% CI: 1.11-3.49; P=0.019).

Conclusions

Preprocedural hyperuricemia, independently from chronic kidney disease (CKD), is a significant and independent predictor of long-term mortality for patients with AMI who underwent PCI.

Clinical characteristics of patients under 40 years old with early-onset hyperuricaemia: a retrospective monocentric study in China

OBJECTIVE

To investigate the clinical characteristics of patients with early-onset hyperuricaemia (HUC).

METHODS

A retrospective study using data from the Second Affiliated Hospital of Soochow University was conducted. 623 patients with HUC were divided into early-onset group and late-onset group. Another 201 healthy subjects ≤40 years old were regarded as control group. The data of physical measurements and biochemistry test were collected. Clinical data of early-onset group were compared with late-onset group and control group by analysis of variance (ANOVA) and χ² test. Principal component analysis (PCA) was applied. Logistic regression was used to identify the clinical factors correlated with patients with early-onset HUC.

RESULTS

The patients of early-onset group had different body mass index (BMI), serum albumin, alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), gamma-glutamyltransferase (GGT), creatinine (Cr), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), TG/high density lipoprotein (HDL) ratio, HDL and percentage of males, hypertension (HBP) as well as fatty liver compared with healthy people in the control group. Early-onset group patients had different albumin, ALT, fasting blood glucose, Cr, percentage of males and HBP compared with late-onset group patients. PCA identified four significant patterns including PC1 (labelled 'TG and HDL'), PC2 (labelled 'fatty liver and liver enzymes'), PC3 (labelled 'TC and LDL') and PC4 (labelled 'AKP'). The results of univariate and multivariate logistic regression analysis showed that BMI, HBP and albumin were correlative factors for early onset of HUC when the patients with early-onset and late-onset HUC were involved, while gender, BMI, PC1, PC2 and PC4 were correlative factors for early-onset HUC when the early-onset and control groups were involved.

CONCLUSION

This study described a group of patients with early-onset HUC with distinct clinical features. Gender, BMI, 'TG and HDL', 'fatty liver and liver enzymes' and 'AKP' have higher values than HBP, type 2 diabetes mellitus and 'TC and LDL' in patients under 40 years old with early-onset HUC.

Relationship between serum uric acid and hypertension: a cross-sectional study in Bangladeshi adults

Experimental evidence suggests a causal role of serum uric acid (SUA) in hypertension development. Currently, there are few data available on the association between SUA and hypertension; data from Bangladeshi adults are not available yet. This study evaluated the association of SUA with hypertension among Bangladeshi adults. Blood samples were obtained from 140 males and 115 females and analyzed for SUA and lipid levels. Hypertension was defined as SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg. All participants were divided into four quartiles based on SUA concentrations. Association of SUA with hypertension was evaluated by logistic regression models. The prevalence of hypertension and prehypertension was significantly higher in male (15.4 and 47.6%, respectively) than in the female (5.6 and 33.4%, respectively) subjects (p < 0.01). Males had a higher mean level of SUA (310.7 ± 67.9 µmol/L) than in the females (255.3 ± 69.3 µmol/L) (p < 0.001). Hyperuricemia was prevalent 9.1% in males and 10.3% in females. An increasing trend for hypertension and prehypertension was found in both genders with increasing SUA levels in the quartiles (p < 0.01). SUA levels in the quartiles were positively correlated with blood pressure (p < 0.01). After adjusting for baseline covariates, SUA levels were significantly associated with hypertension (p < 0.01). Findings of this study indicate the significance of maintaining normal SUA level to prevent hypertension.

Flow-mediated dilation can be used to predict incident hypertension in patients with hyperuricemia

INTRODUCTION

The aim of the study was to evaluate whether flow-mediated dilation (FMD) can be used to predict incident hypertension in patients with hyperuricemia.

MATERIAL AND METHODS

Normotensive participants with and without hyperuricemia at baseline were prospectively enrolled. Flow-mediated dilation was assessed at baseline, and after 1 year's follow-up the incidence of hypertension was compared between those with and without hyperuricemia. The predictive value of baseline FMD for incident hypertension among hyperuricemia patients was evaluated.

RESULTS

A total of 222 participants were included. Mean systolic and diastolic blood pressure (BP) was 129.5 ±8.4 mm Hg and 78.3 ±7.9 mm Hg. Mean serum uric acid (UA) level was 4.4 ±2.8 mg/dl. Mean FMD was 5.1 ±2.7%. Compared to normal UA group, hyperuricemia group had higher proportion of male (58.4% vs. 61.2%), higher systolic BP (125.4 ±7.9 mm Hg vs. 132.1 ±7.3 mm Hg), serum high sensitivity C-reactive protein (3.9 ±2.2 mg/dl vs. 4.5 ±3.0 mg/dl) and UA (3.5 ±1.4 mg/dl vs. 5.7 ±0.7 mg/dl) levels, but lower mean FMD (5.6 ±2.4% vs. 4.8 ±2.0%) (p < 0.05 for all comparisons). No participant in normal UA group developed hypertension, while in hyperuricemia group, 6 participants developed hypertension. In hyperuricemia participants, after adjusted for covariates, per 1-standard deviation decrease in baseline FMD remained significantly associated with 15% increased risk of incident hypertension.

CONCLUSIONS

Patients with hyperuricemia have an increased risk of developing hypertension, and low baseline FMD in hyperuricemia patients is associated with significantly increased risk of incident hypertension.

Impact of Accumulated Serum Uric Acid on Coronary Culprit Lesion Morphology Determined by Optical Coherence Tomography and Cardiac Outcomes in Patients with Acute Coronary Syndrome

Objectives: We aimed to examine the relations of very high levels of serum uric acid (sUA) with features of culprit lesion plaque morphology determined by optical coherence tomography (OCT) and adverse clinical outcomes in patients with acute coronary syndrome (ACS). Methods: We retrospectively compared ACS patients according to sUA levels of > 8.0 mg/dL (n = 169), 7.1–8.0 mg/dL (n = 163), 6.1–7.0 mg/dL (n = 259), and ≤6.0 mg/dL (n = 717). Angiography and OCT findings were analyzed in patients with preintervention OCT and the 4 sUA groups (> 8.0 mg/dL, n = 61; 7.1–8.0 mg/dL, n = 72; 6.1–7.0 mg/dL, n = 131; and ≤6.0 mg/dL, n = 348) were compared. Results: Cardiogenic shock was more prevalent in ACS patients with sUA > 8.0 mg/dL (22% vs. 19% vs. 10% vs. 6%, p < 0.001). Plaque rupture was observed more prevalently by OCT in patients with sUA > 8.0 mg/dL (67% vs. 47% vs. 56% vs. 45%, p = 0.027). At the 2-year follow-up, Kaplan-Meier estimates showed higher cardiac mortality in patients with sUA > 8.0 mg/dL (25% vs. 12% vs. 5% vs. 5%, p < 0.001). After adjusting for traditional cardiovascular risk factors and creatinine levels, patients with sUA > 8.0 mg/dL showed a 4.5-fold increased risk in 2-year cardiac death by multivariate Cox proportional hazard analysis (hazard ratio 4.54, 95% confidence interval 2.98–6.91; p < 0.001). Conclusions: Very high sUA levels like > 8.0 mg/dL are the primary predictor of 2-year cardiac mortality and could partly be caused by adverse effects of accumulated sUA on plaque morphology in patients with ACS.

Assessment of the relationship between serum uric acid and glucose levels in healthy, prediabetic and diabetic individuals

BACKGROUND

In epidemiological studies, serum uric acid (SUA) has been shown to be associated with hypertension and cardiovascular disorders. However, limited studies have evaluated the relationship between SUA and glucose levels in healthy and diabetic individuals and their observed findings are inconsistent. This study aimed to examine the relationship between SUA and fasting blood glucose (FBG) levels among healthy, prediabetic and diabetic individuals in Bangladesh.

METHODS

In total, 310 blood samples were collected from 215 male and 95 female subjects and analyzed for FBG, SUA, and lipid levels. All participants were categorized into four quartiles based on SUA concentrations. Diabetes and prediabetes were defined as FBG level ≥ 126 mg/dL and 100-125 mg/dL, respectively. The association between SUA and diabetes was evaluated by multinomial logistic regression analysis.

RESULTS

The prediabetic and diabetic individuals had a lower mean level of SUA (338.2 ± 101.6 and 290.9 ± 98.2 µmol/L, respectively) compared to healthy (369.5 ± 110.9 µmol/L) individuals (p < 0.001). SUA was positively associated with BMI, TG and TC but negatively associated with FBG. The prevalence of diabetes was decreased with increasing concentration of SUA across the quartiles. In regression analysis, SUA levels were inversely associated with diabetes mellitus.

CONCLUSIONS

SUA levels were high in healthy individuals but declined in prediabetic and diabetic individuals with increasing FBG concentrations. A significant inverse association was observed between the levels of SUA and diabetes in Bangladeshi adults. Further studies are needed to examine the reliability of using SUA to predict diabetes.

Age-differential association between serum uric acid and incident hypertension

Increasing evidence suggests a positive association between the serum uric acid (SUA) level and incident hypertension. However, the association has been inconsistent based on age, sex, body mass index, and lipid profiles. Thus, we investigated whether there is an interaction between SUA and other risk factors on incident hypertension in the Korean general population. In this study, 808 participants aged 40-79 years were included. They were free of hypertension and major cardiovascular disease at baseline. Incident hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg, diastolic blood pressure (DBP) ≥ 90 mmHg, or use of antihypertensive medication. To investigate whether the association between SUA and incident hypertension is modified by other risk factors for hypertension, a generalized linear model and Z test were used. During the mean follow-up of 3.3 years, 11.5% of men and 10.7% of women developed hypertension. The association between SUA and incident hypertension was inconsistent according to participant age (p for interaction = 0.009). The association between SUA level and incident hypertension was positively significant among people aged < 55 years (relative risk 1.74 per 1.0 mg/dL of SUA; p = 0.002), but there was no significant association among people aged ≥ 55 years (p = 0.894). In a secondary analysis, the SUA level was not associated with an increase in SBP, but positively associated with DBP. We observed an age-differential association between SUA level and incident hypertension among Koreans. An increased SUA level can be a trigger for hypertension through early vascular changes in the middle-aged population.

Serum uric acid and high-risk pregnancy: an intriguing correlation in advanced pregnant women

BACKGROUND

The aim of our study is to explore the relationship between serum uric acid (UA) and high-risk pregnancy (HRP) in advanced pregnant women.

METHODS

The study included 226 advanced pregnant women (≥35 years), and the HRP score were assessed according to China HRP score standards.

RESULTS

All data were separated into the three groups according to HRP score, we observed significant increases of serum UA concentrations between the three groups (207.51±42.45; 226.65±45.42 and 228.27±49.70 µmol/L, P=0.017). Notably, serum UA concentrations were found to be positive correlated with HRP score (r=0.165, P=0.013) in advanced pregnant women. Serum UA was independent correlated with HRP score (beta =0.164, P=0.009) in multiple linear regression analysis.

CONCLUSIONS

We conclude that serum UA is correlated with HRP score, and increased serum UA levels may herald HRP in advanced pregnant women.

Relation of Coronary Culprit Lesion Morphology Determined by Optical Coherence Tomography and Cardiac Outcomes to Serum Uric Acid Levels in Patients With Acute Coronary Syndrome

The aims of the present study were to elucidate features of culprit lesion plaque morphology using optical coherence tomography (OCT) in relation to elevated serum uric acid (sUA) levels and to clarify the impact of sUA levels on adverse clinical outcomes in patients with acute coronary syndrome (ACS). Clinical data and outcomes were compared between ACS patients with sUA ≥6 mg/dl (high-sUA; n = 506) and sUA <6.0 mg/dl (low-sUA; n = 608). Angiography and OCT findings were analyzed in patients with preintervention OCT and compared between groups of high-sUA (n = 206) and low-sUA (n = 273). Patients with high-sUA were more frequently male (88% vs 74%, p <0.001), younger (median 65 years vs 67 years, p = 0.017), more obese (median body mass index; 24.3 kg/m² vs 23.2 kg/m², p <0.001), and had a more frequent history of hypertension (72% vs 62%, p <0.001). ACS with lung congestion or cardiogenic shock was more prevalent in patients with high-sUA (30% vs 13%, p <0.001). Plaque rupture (54% vs 42%, p = 0.021) and red thrombi (55% vs 41%, p = 0.010) were more prevalently observed by OCT in patients with high-sUA. Kaplan-Meier estimate survival curves showed that the 2-year cardiac mortality was higher in patients with high-sUA (12.1% vs 4.2%, p <0.001). The multivariate Cox proportional hazard analysis showed that sUA values independently and significantly predicted cardiac death within 2 years (hazard ratio 1.41 [95% confidence interval 1.26 to 1.57], p <0.001). In conclusion, sUA levels are associated with culprit lesion coronary plaque morphology and raised sUA levels affect cardiovascular mortality after adjusting for several cardiovascular risk factors.

Influence of exposure to perfluoroalkyl substances (PFASs) on the Korean general population: 10-year trend and health effects

This study demonstrated the 10-year trend of 13 perfluoroalkyl substances (PFASs) serum levels among 786 adults living in Seoul, Korea. PFAS levels gradually increased from 2006 to 2013, decreasing thereafter. We found that PFAS levels were higher in male than in female participants and were positively correlated with age. PFASs were not significantly correlated with body mass index, although we observed positive correlations with total cholesterol, low-density lipoprotein cholesterol, and triglycerides and negative correlations with high-density lipoprotein cholesterol. Uric acid and free thyroxine (fT4) also showed positive correlations with major congeners while correlations between thyroid stimulating hormone and PFASs were inconsistent. We demonstrated significant correlations between fT4 and perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), and perfluorodecanoic acid (PFDA). There were significant differences in PFHxS and perfluorododecanoic acid (PFDoDA) levels between participants with and without diabetes. Furthermore, principal component analysis suggested possible differences in disease manifestation based on the congener distribution of PFASs. This study is the first study of temporal trends of 13 PFAS congeners in serum samples obtained from the Korean general population; it is currently longest and largest scale study of this type.

Relationship Between Serum Uric Acid and Incident Hypertension in Patients with Type 2 Diabetes

BACKGROUND

Little is known about the relationship between high baseline serum uric acid (SUA) and incident hypertension in patients with type 2 diabetes (T2D).

OBJECTIVES

To evaluate the ability of baseline SUA to predict the incidence of hypertension in non-hypertensive patients with T2D.

METHODS

The association between SUA and mean 20-year incidence of hypertension was examined in 1,666 non-hypertensive patients with T2D from Isfahan Endocrine and Metabolism Research Center outpatient clinics, Iran. The primary outcome was incident hypertension defined as systolic blood pressure (BP) of 140 mmHg or higher and/or diastolic BP 90 mmHg or higher and/or use of antihypertensive medications. The mean (standard error (SE)) age of participants was 49.4 years (0.25 years) with a mean (SE) duration of diabetes of 6.1 years (0.15 years) at initial registration. We used multiple logistic regression to estimate the odds ratio (OR) for the incidence of hypertension across quartiles of SUA, and plotted a receiver operating characteristic (ROC) curve to assess discrimination.

RESULTS

The highest quartile of SUA was not associated with hypertension compared with the lowest quartile in multivariable adjusted models (OR: 1.22, 95% CI: 0.87, 1.73). The area under the ROC curve for SUA was 51.7% (95% CI: 48.9, 54.5).

CONCLUSIONS

High initial SUA levels are not a predictor of incident hypertension in an Iranian T2D population.

The association between serum uric acid and blood pressure in different age groups in a healthy Chinese cohort

High serum uric acid (sUA) has been reported to be a risk factor for hypertension however, whether this is the case for all age groups is not clear. We examined the association between sUA concentrations and systolic and diastolic blood pressure (SBP and DBP) in different age groups in a cohort of healthy Chinese participants.A total of 1082 healthy participants aged from 41 to 70 years were included. sUA concentration was measured by the uricase-peroxidase method. SBP and DBP were assessed using mercury sphygmomanometry. Hypertension was defined as SBP ≥140 mm Hg or DBP ≥90 mm Hg. Hyperuricemia (HUA) was defined as sUA concentration of >7 mg/dL in men and >6 mg/dL in women. The association between sUA concentration and SBP and DBP was examined using Pearson's correlation test, multivariate linear regression, and logistic regression analysis.The prevalence of hypertension and HUA increased with age (P < .001). Hypertension was more common in participants that had HUA than in those that did not (38.95% vs 30.16%, P = .02). Higher sUA was significantly associated with higher SBP and DBP in the 41- to 50-year-old participants (SBP, β = 0.35, P < .001; DBP, β = .29, P < .001; after adjustment for age, sex, total cholesterol, estimated glomerular filtration rate, and fasting plasma glucose). HUA was also a risk factor for hypertension in this age group (odds ratio 1.425, 95% confidence interval, 1.217-1.668, P < .001). There was no association between sUA concentration and SBP and DBP in the other age groups.In this population of healthy Chinese participants, sUA concentration was positively associated with hypertension only in the 41- to 50-year-old group. Lowering uric acid in this age group may help to reduce the incidence of hypertension.

Serum Uric Acid is Independently Associated with Enlarged Perivascular Spaces

Enlarged perivascular spaces (EPVS) are reported to be associated with impaired cognitive function and sleep disorders. It is of clinical importance to understand the risk factors for EPVS. Hyperuricemia increases the risk of hypertension and endothelial dysfunction, which are well recognized to be associated with EPVS. Therefore, we postulated that serum uric acid (SUA) might be associated with EPVS. A total of 665 lacunar stroke patients were enrolled in this study. The SUA concentrations of patients with severe EPVS were much higher than those of patients with mild EPVS (for basal ganglia: 5.25 ± 1.40 mg/dl vs. 4.75 ± 1.40 mg/dl, p < 0.001; for white matter: 5.31 ± 1.41 mg/dl vs. 4.88 ± 1.37 mg/dl, p = 0.009). The percentage of subjects with severe EPVS tended to be higher in the highest quartile of SUA (chi-square test: P = 0.002 for basal ganglia and 0.006 for white matter). Spearman correlation analysis indicated that the SUA concentrations were positively correlated with the severity of EPVS (rho > 0, p < 0.05). Multivariate logistic regression analysis showed that high normal SUA was independently associated with a higher severity of EPVS. This finding suggests that high SUA levels might be an independent risk factor for EPVS in lacunar stroke patients.

Association between serum uric acid level and hypertension in a Chinese elderly rural population

Previous studies have examined the association between elevated serum uric acid (SUA) level and hypertension; however, the association in the Chinese elderly is still uncertain. A cross-sectional study was performed in a rural district of Beijing. A total of 2,397 participants (967 men and 1,430 women) completed the survey. The SUA levels of participants were categorized into four levels using the quartiles (P25, P50, and P75) as cutoff values. Participant was diagnosed as hyperuricemia if the SUA level was ≥417 μmol/L (male) or ≥357 μmol/L (female). Hypertension was defined as systolic blood pressure (BP) ≥140 mmHg and/or diastolic BP ≥90 mmHg and/or receiving antihypertensive drug treatment. Multiple logistic regression was used to estimate the association between SUA and hypertension. We found that higher SUA level was associated with the increased risk of hypertension in both sexes, even after adjusting for potential confounding variables. In total, the risk for having hypertension increased by 0.3% per 1 μmol/L increment in SUA level, increased by 95% for the highest vs. lowest quartile of SUA level, and increased by 111% in the hyperuricemia patients. Moreover, we found that the association was more pronounced in the male participants. There were approximately J-shaped relationships between SUA level (quartiles) and hypertension in all age groups. Higher SUA levels are positively associated with hypertension among the Chinese rural elderly. Further studies are still required to determine the relationship between SUA level and hypertension and to explore its potential biological mechanisms underlying the gender-related association in the elderly population.

ABBREVIATIONS

CVD; cardiovascular disease; BMI: body mass index; BP: blood pressure; SUA: serum uric acid; TC: total cholesterol; TG: triglycerides; HDL-C: high-density lipoprotein; LDL-C: low-density lipoprotein; FPG: fasting blood glucose; OR: odds ratio; CI: confidence interval; SD: standard deviation.

An examination of the relationship between serum uric acid level, a clinical history of gout, and cardiovascular outcomes among patients with acute coronary syndrome

BACKGROUND

Studies have suggested a relationship between higher baseline serum uric acid (sUA) levels and an elevated risk of subsequent ischemic cardiovascular outcomes among acute coronary syndrome (ACS) patients; this relationship may be modified by a clinical history of gout and has not been studied in large patient cohorts. We sought to understand the effect of sUA and gout on ACS outcomes.

METHODS

Using PLATO and TRACER data on 27,959 ACS patients, we evaluated baseline sUA levels in relation to a composite of cardiovascular death, myocardial infarction (MI), or stroke. We assessed interaction terms to determine if a baseline clinical diagnosis of gout modified this putative relationship; 46% (n=12,882) had sUA levels elevated >6.0 mg/dL.

RESULTS

Patients with elevated levels were more often male with a history of prior MI, diabetes, and heart failure compared with those with sUA <6.0 mg/dL. The unadjusted risk of the composite endpoint increased with corresponding elevations in sUA levels (per 1 mg/dL increase) (HR=1.23 [95% CI: 1.20-1.26]) above the statistical inflection point of 5.0 mg/dL. After adjustment, the association between sUA level and the composite outcome remained significant (HR=1.07 [95% CI: 1.04-1.10]), and baseline gout did not modify this relationship.

CONCLUSIONS

In patients with ACS, increasing levels of sUA are associated with an elevated risk of cardiovascular events, regardless of a clinical diagnosis of gout. Further investigation is warranted to determine the mechanism behind this relationship and to delineate whether sUA is an appropriate therapeutic target to reduce cardiovascular risk.

Serum uric acid on admission predicts in-hospital mortality in patients with acute coronary syndrome

BACKGROUND

Despite the association between uric acid and cardiovascular disease has been known for decades, the prognostic value of serum uric acid (UA) in all clinical manifestations of acute coronary syndrome (ACS), namely ST-elevation myocardial infarction (STEMI), NSTEMI and unstable angina, has not been definitively assessed.

METHODS

This retrospective analysis included patients from previous SPAI and FAMI studies with the aim to investigate the association between serum uric acid and major adverse cardiovascular events at 180days from hospital admission.

RESULTS

1548 patients were considered and divided in four groups, according UA concentration. Uricemia was significantly associated with gender, BMI, arterial hypertension, HDL-cholesterol, triglycerides, metabolic syndrome and glomerular filtration rate in univariate analysis. Multivariate logistic regression indicated that UA >6.0mg/dL on admission increased the risk of in-hospital mortality in overall population (OR 2.9, 95%CI 1.4-6.1; p=0.0057) and in patients with de novo ACS (OR 3.2, 95%CI 1.5-6.8; p=0.0033). Comparable results were also obtained after adjusting the model for age, gender, body mass index, glomerular filtration rate, metabolic syndrome, acute revascularization and ethnicity. A positive correlation was observed between UA and C reactive protein concentrations in in-hospital deaths only (rho 0.41, p=0.027).

CONCLUSION

In patients with acute coronary syndrome, uricemia levels above the current international reference limit (6.0mg/dl) were associated with in-hospital mortality, independently from ethnicity and renal function.