Association between serum uric acid and the metabolic syndrome among a middle- and old-age Chinese population

The Association Between Serum Uric Acid Levels and the 10-Year Prospective Risk of Dyslipidemia: A Cohort Study From Healthy Heart Project (YHHP)

Background and Aims

Dyslipidemia is a major risk factor for cardiovascular disease (CVD) and is increasingly prevalent globally, particularly in developing countries undergoing lifestyle transitions. Serum uric acid (SUA) has been implicated in various metabolic disorders, including dyslipidemia. This study aimed to evaluate the association between high SUA and the 10-year prospective risk of dyslipidemia.

Methods

This cohort study uses data from the Yazd Healthy Heart Project (YHHP). Participants were followed for 10 years, during which the association between dyslipidemia incidence and SUA levels was assessed using multivariate Cox proportional hazard models.

Results

Among 693 participants analyzed, higher SUA quartiles were associated with older age, male gender, and adverse anthropometric and metabolic profiles. Elevated SUA levels correlated positively with triglycerides (r = 0.21, p < 0.001), total (r = 0.13, p < 0.001) and low-density lipoprotein cholesterol (r = 0.12, p = 0.001) levels, but not with high-density lipoprotein cholesterol (r = 0.07, p > 0.05). After adjusting for age, lifestyle factors, and metabolic parameters, the incidence of dyslipidemia increased across SUA quartiles in males, with adjusted hazard ratios of 1.33 (95% CI: 0.90-1.97), 1.66 (95% CI: 1.10-2.54), and 1.79 (95% CI: 1.17-2.72) for the second, third, and fourth quartiles of SUA, respectively (p for trend 0.001), but not in females: 1.11 (95% CI: 0.59-2.06), 0.95 (95% CI: 0.55-1.64), and 1.14 (95% CI: 0.60-2.16), respectively, p for trend 0.86.

Conclusion

Elevated SUA levels independently associated with the development of dyslipidemia over a decade in an Iranian population. The findings underscore the potential utility of SUA as a biomarker for assessing dyslipidemia risk, particularly in men. Further research should explore mechanistic pathways linking SUA to dyslipidemia and evaluate interventions targeting SUA reduction to mitigate dyslipidemia risk.

Associations between serum uric acid and depression in U.S. adults: An analysis of the national health and nutrition examination survey 2007-2016

Limited research has specifically explored the gender-specific differences in relation to serum uric acid and depression. Therefore, the research aims to bridge that gap by exploring the relationships between serum uric acid and depression, stratified by gender, in U.S. adults. In this study, the participants comprised individuals from five consecutive survey cycles (NHANES 2007-2008-2015-2016), with 20,804 qualified participants incorporated into the research. The assessment of depression was conducted utilizing the Patient Health Questionnaire-9 (PHQ-9), and we calculated the weighted averages (95% CIs) for continuous variables and the percentages (95% CIs) for categorical variables among the chosen covariates. A multivariable logistic regression model with weights was utilized to assess the relationships between serum uric acid categories and depression status. In male subjects, uric acid levels may be linked inversely to depression. However, Tertile 3 (≥303.3 µmol/L) was more likely to develop depression than Tertile 1 (<249.8 µmol/L) among women. The study shows that high serum uric acid level may reduce the incidence of depression in men, but in females, it is an independent factor that increases the risk of depression.

Uncovering the Potential Mechanisms and Effects of Hyperuricemia and its Associated Diseases on Male Reproduction

Male fertility and metabolic disorders, including obesity and diabetes, are closely connected. Since hyperuricemia and metabolic syndrome are strongly related, male fertility and hyperuricemia may, to some degree, be associated. According to recent studies, hyperuricemia imposes various effects on sex hormones, semen quality, and male erectile dysfunction. Some researchers claim that uric acid worsens male semen and raises the risk of erectile dysfunction (ED), while others state that it safeguards both penile erection and male semen. Additionally, it has been shown that gout and metabolic syndrome also raise the risk of ED. To clarify this controversy, the influence and potential mechanisms of hyperuricemia on ED, semen quality, sex hormone levels, and the effects of hyperuricemia-related disorders on ED will be comprehensively summarized.

A high level of uric acid is associated with long-term adverse cardiovascular outcomes in patients who received fractional flow reserve with coronary intermediate stenosis

BACKGROUND AND AIMS

The role of fractional flow reserve (FFR) in coronary intermediate lesions is widely recommended by guidelines. The effect of uric acid (UA) on cardiovascular events is also well known. However, the relationship between UA and long-term cardiovascular outcomes in patients who received FFR with intermediate lesions remains unknown.

METHODS AND RESULTS

We retrospectively included 428 patients who underwent both coronary angiography (CAG) and FFR. Participants were stratified into two groups based on the median UA. The primary endpoint was the composite of major adverse cardiovascular and cerebrovascular events (MACCEs), including repeat revascularization, nonfatal stroke, nonfatal myocardial infarction, and all-cause death. A Cox proportional hazards model was utilized to analyze the association between UA and the prevalence of MACCEs. During a median follow-up of 5.8 years, a higher MACCEs rate occurred in the high UA group compared to the low UA group (16.8% vs. 5.1%, p log-rank<0.01). Elevated UA was independently linked to a higher incidence of MACCEs, whether UA was treated as a categorical or continuous variable (hazard ratio [HR] 2.76, 95% confidence interval [CI] 1.27-6.03 or HR 1.01, 95% CI 1.01-1.02). The restricted cubic spline (RCS) analysis illustrated that the HR for MACCEs increased with increasing UA.

CONCLUSION

The present study demonstrates that UA is associated with MACCEs risk and suggests that UA is a reliable predictor of long-term cardiovascular events in coronary intermediate stenosis patients.

The role of body mass index on the association between the energy-adjusted dietary inflammatory index and hyperuricemia: a mediation analysis based on NHANES (2007-2016)

BACKGROUND

The Energy-Adjusted Dietary Inflammatory Index (E-DII) is related to both body mass index (BMI) and hyperuricemia. However, the association among BMI, hyperuricemia and DII is yet to be fully elucidated. The purpose of this study is to explore the role of BMI in the relationship between E-DII and hyperuricemia in the American population.

METHODS

A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2007 to 2016, with a sample size of 10,571 participants. The study used a weighted logistic regression model and a generalized additive model (GAM) to explore the associations among BMI, hyperuricemia and E-DII. Furthermore, mediation analysis was utilized to illustrate the mediating relationships among these variables.

RESULTS

The results of the study indicated that a higher E-DII was related to an increased risk of hyperuricemia. The association between E-DII and hyperuricemia was partially mediated by BMI.

CONCLUSIONS

E-DII is associated with hyperuricemia. BMI mediates the relationship between E-DII and hyperuricemia among Americans, which provides crucial information for the prevention of hyperuricemia.

Ruminal microbiota and muscle metabolome characteristics of Tibetan plateau yaks fed different dietary protein levels

Introduction

The dietary protein level plays a crucial role in maintaining the equilibrium of rumen microbiota in yaks. To explore the association between dietary protein levels, rumen microbiota, and muscle metabolites, we examined the rumen microbiome and muscle metabolome characteristics in yaks subjected to varying dietary protein levels.

Methods

In this study, 36 yaks were randomly assigned to three groups (n = 12 per group): low dietary protein group (LP, 12% protein concentration), medium dietary protein group (MP, 14% protein concentration), and high dietary protein group (HP, 16% protein concentration).

Results

16S rDNA sequencing revealed that the HP group exhibited the highest Chao1 and Observed_species indices, while the LP group demonstrated the lowest. Shannon and Simpson indices were significantly elevated in the MP group relative to the LP group (P < 0.05). At the genus level, the relative abundance of Christensenellaceae_R-7_group in the HP group was notably greater than that in the LP and MP groups (P < 0.05). Conversely, the relative abundance of Rikenellaceae_RC9_gut_group displayed an increasing tendency with escalating feed protein levels. Muscle metabolism analysis revealed that the content of the metabolite Uric acid was significantly higher in the LP group compared to the MP group (P < 0.05). The content of the metabolite L-(+)-Arabinose was significantly increased in the MP group compared to the HP group (P < 0.05), while the content of D-(-)-Glutamine and L-arginine was significantly reduced in the LP group (P < 0.05). The levels of metabolites 13-HPODE, Decanoylcarnitine, Lauric acid, L-(+)-Arabinose, and Uric acid were significantly elevated in the LP group relative to the HP group (P < 0.05). Furthermore, our observations disclosed correlations between rumen microbes and muscle metabolites. The relative abundance of NK4A214_group was negatively correlated with Orlistat concentration; the relative abundance of Christensenellaceae_R-7_group was positively correlated with D-(-)-Glutamine and L-arginine concentrations.

Discussion

Our findings offer a foundation for comprehending the rumen microbiome of yaks subjected to different dietary protein levels and the intimately associated metabolic pathways of the yak muscle metabolome. Elucidating the rumen microbiome and muscle metabolome of yaks may facilitate the determination of dietary protein levels.

High prevalence of hyperuricemia and the association with metabolic syndrome in the rural areas of Southwestern China: A structural equation modeling based on the Zhuang minority cohort

BACKGROUND AND AIMS

The prevalence of hyperuricemia (HUA) and metabolic syndrome (MetS) in the Zhuang minority had not been examined. We aimed to determine the prevalence of HUA and MetS, and explore the interrelationship among the serum uric acid to creatinine (SUA/Cr) ratio, MetS, and its components.

METHODS AND RESULTS

A cross-sectional study was conducted with structured questionnaire and physical examination based on the Zhuang minority cohort. A Structural Equation Model was performed to examine the hypothesis link between the SUA/Cr ratio, MetS, and its components. 10,902 aged 35-74 years Zhuang minority adults were included. The total prevalence of HUA and MetS was 17.5% and 23.7%, respectively. The SUA/Cr ratio had a positive effect on MetS (the standardized coefficient βr was 0.311 in males and 0.401 in females). The SUA/Cr ratio was positively associated with obesity (βr = 0.215), dyslipidemia (βr = 0.177), and high blood pressure (βr = 0.034) in males and was positively associated with obesity (βr = 0.303), dyslipidemia (βr = 0.162), and hyperglycemia (βr = 0.036) in females.

CONCLUSIONS

The prevalence of HUA in the aged 35-74 years Zhuang minority adults was high while the prevalence of MetS was relatively low. As HUA is an earlier-onset metabolic disorder and the SUA/Cr ratio had a positive effect on MetS and its components, the prevention measures of MetS should be strengthened. And the SUA/Cr ratio can be used as an early warning sign to implement the intervention measures of MetS.

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 between the Weight-Adjusted Waist Index and Serum Uric Acid: A Cross-Sectional Study

Background

Serum uric acid (SUA) was closely related to body metabolism. This study aimed to investigate the relationship between the adult weight-adjusted waist index (WWI) and SUA.

Methods

In the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2020, 6494 eligible participants aged ≥20  were included. The multivariate logistic regression model was used to test the correlation between WWI and SUA. At the same time, subgroup analysis was carried out by using multivariate logistic regression according to age, sex, and race. Then, the fitting smooth curve was applied to solve the association between WWI and SUA. Finally, the recursive algorithm was used to calculate the inflection point in the nonlinear relationship, and the two-stage piecewise linear regression model was used to analyze the relationship between WWI and SUA on both sides of the inflection point.

Results

In all the 6494 participants, through the fully adjusted model, this study found that there was a positive correlation between WWI and SUA (β = 5.64; 95% CI: 2.62 and 8.66). In addition, this positive correlation still had certain statistical significance in the subgroup analysis stratified by sex, age, and race. Our research team found a significant positive correlation between the WWI and SUA in females, but the correlation was not significant in males. We also found a small inverted U-shaped curve between the WWI and SUA in men when we stratified the sex subgroups. The small inflection point was determined to be 11.5 cm/√ kg. In racial subgroup analysis, we also found a U-shaped relationship between the WWI and SUA in non-Hispanic White and other race/ethnicity (the inflection point was 11.08 cm/√ kg and 12.14 cm/√ kg, respectively).

Conclusion

This study showed that the WWI was a newly developed and new predictor of centripetal obesity independent of body weight and there was a positive correlation between the WWI and SUA.

Prevalence and Risk Factors of Comorbid Obesity in Chinese Patients with Bipolar Disorder

Purpose

Bipolar disorder (BD) predisposes patients to comorbid obesity and increases the risk of metabolic syndrome and cardiovascular disease. In this study, we investigated the prevalence of comorbid obesity and its risk factors in patients with BD in China.

Patients and Methods

We conducted a cross-sectional retrospective survey of 642 patients with BD. Demographic data were collected, physical examinations were performed, and biochemical indexes, including fasting blood glucose, alanine aminotransferase (ALT), aspartate aminotransferase, and triglycerides (TG) levels, were measured. Height and weight were measured on an electronic scale at admission, and body mass index (BMI) was in kg/m². Pearson's correlation analysis was used to analyze the correlation between BMI and variable indicators. Multiple linear regression analysis was used to analyze the risk factors for comorbid obesity in patients with BD.

Results

The prevalence of comorbid obesity in Chinese patients with BD was 21.3%. Obese patients had high levels of blood glucose, ALT, glutamyl transferase, cholesterol, apolipoprotein B (Apo B), TG, and uric acid in the plasma; however, the levels of high-density lipoprotein and apolipoprotein A1 were lower than those in non-obese patients. Partial correlation analysis showed that BMI was associated with ApoB, TG, uric acid, blood glucose, GGT, TC, ApoA1, HDL, and ALT levels. Multiple linear regression showed that ALT, blood glucose, uric acid, TG, and Apo B levels were important risk factors of BMI.

Conclusion

The prevalence of obesity is higher in patients with BD in China, and TG, blood glucose, liver enzymes, and uric acid are closely related to obesity. Therefore, more attention should be paid to patients with comorbid obesity. Patients should be encouraged to increase their physical activity, control sugar and fat intake, and reduce the prevalence of comorbid obesity and risk of serious complications.

Serum Urate and Risk of Chronic Kidney Disease: A Mendelian Randomization Study Using Taiwan Biobank

OBJECTIVE

To evaluate the association between serum urate and risk of incident chronic kidney disease (CKD) and to assess whether serum urate plays a causal role in CKD.

PATIENTS AND METHODS

We conducted a prospective cohort study and Mendelian randomization analysis that analyzed longitudinal data from the Taiwan Biobank between January 1, 2012, and December 31, 2021.

RESULTS

A total of 34,831 individuals met the inclusion criteria, of which 4697 (13.5%) had hyperuricemia. After a median (interquartile range) follow-up of 4.1 (3.1-4.9) years, 429 participants developed CKD. After adjustment for age, sex, and comorbid conditions, each mg/dL increase in serum urate was associated with a 15% higher risk of incident CKD (HR, 1.15; 95% CI, 1.08 to 1.24; P<.001). The genetic risk score and seven Mendelian randomization methods revealed no significant association between serum urate levels and the risk of incident CKD (HR, 1.03; 95% CI, 0.72 to 1.46; P=0.89; all P>.05 for 7 Mendelian randomization methods).

CONCLUSION

This prospective, population-based cohort study showed that elevated serum urate is a significant risk factor for incident CKD; however, Mendelian randomization analyses failed to provide evidence that serum urate had a causal effect on CKD in the East Asian population.

Impaired sensitivity to thyroid hormones is associated with hyperuricemia in a Chinese euthyroid population

Objective

Impaired sensitivity to thyroid hormones has been reported as a common metabolic disorder, and it remains poorly understood whether it interplays with uric acid (UA) metabolism as an established risk factor for cardiovascular diseases (CVDs). We aimed to investigate the relationship between thyroid hormone sensitivity and elevated UA in a Chinese euthyroid population.

Methods

A total of 15,955 euthyroid subjects were included in this study. Thyroid hormone sensitivity indices were calculated, including the thyroid feedback quantile-based index (TFQI), the Chinese-referenced parametric TFQI (PTFQI), the TSH index (TSHI), and the thyrotropin thyroxine resistance index (TT4RI), and the FT3/FT4 ratio. Linear and logistic regression analyses were performed to detect the association between thyroid hormone sensitivity and elevated UA.

Results

Subjects with reduced sensitivity to thyroid hormones had increased UA levels in both genders (p for trend < 0.001). Logistic and linear regression analyses showed that higher TFQI, PTFQI, TSHI, and TT4RI were positively associated with elevated UA levels, but negatively associated with the FT3/FT4 ratio. The odds ratio (OR) of the highest versus the first quartile of TFQI was 1.20 (1.05, 1.38) in men and 1.80 (1.46, 2.23) in women (p < 0.001). PTHQI, TSHI, and TT4RI obtained similar results in both genders. Conversely, the highest quartile of the FT3/FT4 ratio was negatively correlated with elevated UA levels [men: OR 0.78 (0.68,0.89), women: OR 0.66 (0.53,0.81)].

Conclusion

Impaired sensitivity to thyroid hormones was associated with elevated UA levels in euthyroid subjects. Our findings shed light on the role of thyroid hormone sensitivity in UA metabolism.

Prevalence of hyperuricemia in patients with severe obesity and the relationship between serum uric acid and severe obesity: A decade retrospective cross-section study in Chinese adults

OBJECTIVE

Undoubtedly, the relationship between serum uric acid (SUA) and obesity is less data for Chinese patients with obesity. This study aimed to examine the prevalence of hyperuricemia (HUA) and the association between SUA and patients with obesity.

METHODS

All participants were categorized as overweight, obesity I, obesity II, and obesity III. In addition, based on SUA concentration, the participants were stratified into four quartiles. The authors used descriptive analysis, independent t-test, ANOVA, correlation analysis, and multiple linear regression models to verify the SUA level and obesity among Chinese adults.

RESULTS

Overall, the estimated prevalence of HUA was 69.8%. In the BMI categories, the prevalence of HUA was 5.1% in overweight, 15.2% in obesity I, 16.9% in obesity II, and 32.5% in obesity III. Correlation analysis shows that SUA is strongly correlated with BMI, waist circumference (WC), and hip circumference (HC). Multiple linear regression analysis shows that high density-lipoprotein cholesterol (HDL-C) is a protective predictor of serum uric acid levels in patients with obesity. Compared with the overweight, obesity I, obesity II, and obesity III were more likely to have higher levels in the SUA levels.

CONCLUSION

We mainly showed that the serum uric acid levels in Chinese patients with severe obesity declined slightly as age increased.

Temporal changes in serum uric acid and risk for metabolic syndrome: a longitudinal cohort study

BACKGROUND

Studies suggested elevated serum uric acid (SUA) levels are associated with metabolic syndrome (MetS). However, it remains unclear whether baseline SUA and temporal changes predict MetS. The study aimed to investigate the association of baseline SUA and its temporal longitudinal changes with subsequent risk of MetS.

METHODS

We conducted a retrospective longitudinal cohort study among 44,176 healthy participants aged 18 years and older without MetS at enrollment. The baseline levels and longitudinal changes of SUA were categorized by gender-specific quintiles. Participants were followed to identify newly developed MetS. We employed Cox model to investigate the relationship between SUA and MetS in men and women separately.

RESULTS

During a median follow-up of 2.4 years, 5461 (12.36%) participants developed MetS. After adjustment of demographic, major clinical factors, a higher level of baseline SUA was associated with a significant higher risk of MetS. The corresponding HRs (95% CIs) comparing participants at extreme quintiles were 2.59 (2.32, 2.88) in men and 2.87 (2.41, 3.43) in women. Larger longitudinal absolute increase in SUA was also related to an increases risk of MetS (top vs bottom quintile, 1.70 [1.53, 1.89] in men and 1.94 [1.65, 2.28] in women), regardless the level of baseline SUA. Similarly, the HRs about SUA longitudinal percentage changes were 1.74 (1.56, 1.94) in men and 2.01 (1.69, 2.39) in women, respectively. Moreover, we observed the highest risk of MetS among participants with both higher baseline SUA and larger longitudinal increase in SUA.

CONCLUSION

Higher baseline SUA and larger temporal increase in SUA independently predicted risk of MetS, highlighting the importance of longitudinal SUA monitoring and management for primary prevention of MetS in the general population.

The Association Between Total Percent Fat and Serum Uric Acid in Adults

Background

Serum uric acid (SUA) has been proven to be closely associated with metabolic abnormalities, including obesity. This study aimed to investigate the detailed relationship between total percent fat (TPF) and SUA among adults.

Methods

Briefly, 23,715 adults aged 18–59 years in the National Health and Nutrition Examination Survey (NHANES) 1999–2018 were included in this study. Multivariable linear regression models were used to examine the association between TPF and SUA. Subgroup analyses stratified by sex and obesity status were also performed by multivariable linear regression. Then, fitted smoothing curves and generalized additive models were also applied to address the non-linear relationship between TPF and SUA. Finally, a recursive algorithm was used to calculate the inflection point in the non-linear relationship and a two-segment piecewise linear regression model was used to analyze the relationship between TPF and SUA on both sides of the inflection point.

Results

There were 15,808 (66.7%) obese individuals in all 23,715 participants. In the fully adjusted model, there was a positive association between TPF and SUA (β = 0.99, 95% CI: 0.73–1.26). Besides, this positive association remained statistically significant in subgroup analyses stratified by sex and obesity status. Interestingly, in males, the association of TPF and SUA was an inverted U-shaped curve (inflection point: 34.3%).

Conclusion

Our study revealed a significant positive relationship between TPF and SUA among adults and this association remained statistically significant when stratified by sex and obesity status, but the shape of the smoothing curve in males differed from that in females.

No Evidence for a Causal Link between Serum Uric Acid and Nonalcoholic Fatty Liver Disease from the Dongfeng-Tongji Cohort Study

Background and Aims

Elevated serum uric acid (SUA) is associated with an increased risk of nonalcoholic fatty liver disease (NAFLD); however, whether this association is causal is undetermined.

Methods

Each participant from the Dongfeng-Tongji cohort study based on 27,009 retirees was interviewed face-to-face following a clinical examination. Covariance, logistic regression analysis, and instrumental variables were used to assess associations between SUA and (severity of) NAFLD and the causal link.

Results

Among 8,429 subjects free of NAFLD at baseline, 2,007 participants developed NAFLD after 5 years of follow-up. The multivariable-adjusted odds ratio (OR) for NAFLD for individuals in the fourth quartile of SUA level versus those in the first was 1.71 (95% CI: 1.45-2.01, P for trend <0.001) and was more dramatic in women or normal-weight persons. Furthermore, SUA was materially associated with greater mean markers of hepatic necroinflammation and greater probabilities of fibrosis. In genetic analyses, both single nucleotide polymorphisms (rs11722228 to SLC2A9 and rs2231142 to ABCG2) were pronouncedly associated with increased SUA concentrations, ranging from 0.19 to 0.22 mg/dl. No significant associations were observed between SNPs and potential confounders. No association was observed between the SUA-increasing allele and NAFLD, with an OR of 0.98 (95% CI: 0.90-1.08) per genetic score. This was not significantly different (P = 0.25) from what was expected (1.03, 95% CI: 1.03-1.03).

Conclusions

SUA was positively associated with NAFLD incidence especially in female and normal-weight individuals and the suspected progression risk of newly developed NAFLD. However, the Mendelian randomization analyses lend no causal evidence, suggesting high SUA as a marker and not a cause of NAFLD.

Excess comorbidities in gout: the causal paradigm and pleiotropic approaches to care

Gout is a common hyperuricaemic metabolic condition that leads to painful inflammatory arthritis and a high comorbidity burden, especially cardiometabolic-renal (CMR) conditions, including hypertension, myocardial infarction, stroke, obesity, hyperlipidaemia, type 2 diabetes mellitus and chronic kidney disease. Substantial advances have been made in our understanding of the excess CMR burden in gout, ranging from pathogenesis underlying excess CMR comorbidities, inferring causal relationships from Mendelian randomization studies, and potentially discovering urate crystals in coronary arteries using advanced imaging, to clinical trials and observational studies. Despite many studies finding an independent association between blood urate levels and risk of incident CMR events, Mendelian randomization studies have largely found that serum urate is not causal for CMR end points or intermediate risk factors or outcomes (such as kidney function, adiposity, metabolic syndrome, glycaemic traits or blood lipid concentrations). Although limited, randomized controlled trials to date in adults without gout support this conclusion. If imaging studies suggesting that monosodium urate crystals are deposited in coronary plaques in patients with gout are confirmed, it is possible that these crystals might have a role in the inflammatory pathogenesis of increased cardiovascular risk in patients with gout; removing monosodium urate crystals or blocking the inflammatory pathway could reduce this excess risk. Accordingly, data for CMR outcomes with these urate-lowering or anti-inflammatory therapies in patients with gout are needed. In the meantime, highly pleiotropic CMR and urate-lowering benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors and key lifestyle measures could play an important role in comorbidity care, in conjunction with effective gout care based on target serum urate concentrations according to the latest guidelines.

Comparative analysis of anthropometric indices with serum uric acid in Iranian healthy population

BACKGROUND

The relationship between elevated serum uric acid (SUA) levels and hypertension, metabolic syndrome and cardiovascular disease has been established. In this study, the relation of SUA levels to anthropometric indices, blood cell count and lipid profile was examined.

METHODS

Anthropometric parameters including body-mass index, waist circumference, waist to height ratio, waist to hip ratio, waist to pelvic ratio, neck circumference (NC), body fat mass (BFM), basal metabolic rate (BMR), visceral fat level (VFL) and percent body fat (PBF), along with complete blood cell count, lipid profile and SUA were obtained from 2921 young and middle-aged Iranian healthy subjects. To assess the normality of data, the Kolmogorov-Smirnov test was used. Mann-Whitney, Kruskal-Wallis, Chi-square and Spearman correlation tests were used for evaluating the association between variables. Simple and multiple regression analyses were also performed.

RESULTS

The results of data analysis showed all studied factors were correlated with SUA level except VFL, BFM, and platelet-to-lymphocyte ratio. The highest correlation was with NC, BMR, hematocrits (HCT) and triglycerides (TG). The backward method revealed that TG, LDL, HDL, neutrophil, lymphocyte, platelet, HCT, BMR and skinfold fat thickness were factors related to SUA.

CONCLUSIONS

According to the finding of this study, SUA level is related to anthropometric indices, lipid profile and neutrophil to lymphocyte ratio in healthy population. SUA measurement might be advisable to identify those at increased risk of health problems whom might benefit from further evaluation.

Can biomarkers be used to improve diagnosis and prediction of metabolic syndrome in childhood cancer survivors? A systematic review

Childhood cancer survivors (CCS) are at increased risk to develop metabolic syndrome (MetS), diabetes, and cardiovascular disease. Common criteria underestimate adiposity and possibly underdiagnose MetS, particularly after abdominal radiotherapy. A systematic literature review and meta-analysis on the diagnostic and predictive value of nine newer MetS related biomarkers (adiponectin, leptin, uric acid, hsCRP, TNF-alpha, IL-1, IL-6, apolipoprotein B (apoB), and lipoprotein(a) [lp(a)]) in survivors and adult non-cancer survivors was performed by searching PubMed and Embase. Evidence was summarized with GRADE after risk of bias evaluation (QUADAS-2/QUIPS). Eligible studies on promising biomarkers were pooled. We identified 175 general population and five CCS studies. In the general population, valuable predictive biomarkers are uric acid, adiponectin, hsCRP and apoB (high level of evidence), and leptin (moderate level of evidence). Valuable diagnostic biomarkers are hsCRP, adiponectin, uric acid, and leptin (low, low, moderate, and high level of evidence, respectively). Meta-analysis showed OR for hyperuricemia of 2.94 (age-/sex-adjusted), OR per unit uric acid increase of 1.086 (unadjusted), and AUC for hsCRP of 0.71 (unadjusted). Uric acid, adiponectin, hsCRP, leptin, and apoB can be alternative biomarkers in the screening setting for MetS in survivors, to enhance early identification of those at high risk of subsequent complications.

Erectile dysfunction in hyperuricemia: A prevalence meta-analysis and meta-regression study

BACKGROUND

Whether and to what extent an association exists between hyperuricemia and erectile dysfunction (ED) has not yet been fully determined.

OBJECTIVE

To define pooled prevalence estimates and correlates of erectile dysfunction in men with hyperuricemic disorders.

MATERIALS AND METHODS

A thorough search of Medline, Scopus, and Cochrane Library databases was performed. Data were combined using random-effects models and the between-study heterogeneity was assessed by Cochrane's Q and I² tests. A funnel plot was used to assess publication bias.

RESULTS

Overall, 8 studies included gave information about 85,406 hyperuricemic men, of whom 5023 complained of erectile dysfunction, resulting in a pooled erectile dysfunction prevalence estimate of 33% (95% Confidence Interval: 13-52%; I² = 99.9%). The funnel plot suggested the presence of a publication bias. At the meta-regression analyses, among the available covariates that could affect estimates, only type 2 diabetes mellitus was significantly associated with a higher prevalence of erectile dysfunction (β = 0.08; 95% Confidence Interval: 0.01, 0.15, p = 0.025). At the sub-group analysis, the pooled erectile dysfunction prevalence decreased to 4% (95% Confidence Interval: 0%-8%) when only the largest studies with the lowest prevalence of type 2 diabetes mellitus were included and increased up to 50% (95% Confidence Interval: 17%-84%) when the analysis was restricted to studies enrolling smaller series with higher prevalence of type 2 diabetes mellitus.

CONCLUSIONS

A not negligible proportion of men with hyperuricemia can complain of erectile dysfunction. While a pathogenetic contribution of circulating uric acid in endothelial dysfunction cannot be ruled out, the evidence of a stronger association between hyperuricemia and erectile dysfunction in type 2 diabetes mellitus points to hyperuricemia as a marker of systemic dysmetabolic disorders adversely affecting erectile function.

The Impact of Uric Acid and Hyperuricemia on Cardiovascular and Renal Systems

The description of gout dates back almost 5000 years, and scientific interest in uric acid increased when it was found to be involved in the pathogenesis of gout. Since then, many basic and clinical studies have assessed the implications of uric acid for the oxidative system, inflammation, and cardiovascular and renal outcomes. Uric acid-lowering therapy failed to improve clinical hard outcomes in asymptomatic hyperuricemia, and it is retained in symptomatic hyperuricemia. Dietary and lifestyle modifications are critical to manage hyperuricemia. More studies are warranted to investigate the role of uric acid-lowering drugs on cardiovascular outcomes.

Dose-response relationship between distinct serum uric acid trajectories and metabolic syndrome risk: A 5-year prospective cohort study

BACKGROUND AND AIMS

Although high serum uric acid (SUA) at baseline has been linked to increased risk for metabolic syndrome (MetS), the association of longitudinal SUA changes with MetS risk is unclear. We aimed to examine the effect of distinct SUA trajectories on new-onset MetS risk by sex in a Chinese cohort.

METHODS AND RESULTS

A total of 2364 women and 2770 men who were free of MetS in 2013 were enrolled in this study and followed up to 2018. Group-based trajectory modeling was applied to identify SUA trajectories. Cox proportional hazards model was used to evaluate the association between SUA trajectory and new-onset MetS. The dose-response relationship between SUA trajectories and MetS risk was examined by treating trajectory groups as a continuous variable. During a median follow-up of 48.0 months, 311 (13.16%) women and 950 (34.30%) men developed MetS. SUA trajectories (2013-2018) were defined as four distinct patterns in both women and men: "low", "moderate", "moderate-high", and "high". Compared with "low" SUA trajectory, the adjusted hazard ratio for incident MetS among participants with "moderate", "moderate-high" and "high" trajectory was in a dose-response manner: 1.75 (95% CI: 1.08-2.82), 1.94 (95% CI: 1.20-3.14), and 3.05 (95% CI: 1.81-5.13), respectively, for women; 1.20 (95% CI: 0.97-1.49), 1.48 (95% CI: 1.19-1.85), and 1.66 (95% CI: 1.25-2.21), respectively, for men.

CONCLUSIONS

Elevated SUA trajectories are associated with increased risk for new-onset MetS in women and men. Monitoring SUA trajectories may assist in identifying subpopulations at higher risk for MetS.

Association between serum uric acid and obesity in Chinese adults: a 9-year longitudinal data analysis

OBJECTIVES

Hyperuricaemia has been reported to be significantly associated with risk of obesity. However, previous studies on the association between serum uric acid (SUA) and body mass index (BMI) yielded conflicting results. The present study examined the relationship between SUA and obesity among Chinese adults.

METHODS

Data were collected at Guangdong Second Provincial General Hospital in Guangzhou City, China, between January 2010 and December 2018. Participants with ≥2 medical check-up times were included in our analyses. Physical examinations and laboratory measurement variables were obtained from the medical check-up system. The high SUA level group was classified as participants with hyperuricaemia, and obesity was defined as BMI ≥28 kg/m². Logistic regression model was performed for data at baseline. For all participants, generalised estimation equation (GEE) model was used to assess the association between SUA and obesity, where the data were repeatedly measured over the 9-year study period. Subgroup analyses were performed by gender and age group. We calculated the cut-off values for SUA of obesity using the receiver operating characteristic curves (ROC) technique.

RESULTS

A total of 15 959 participants (10 023 men and 5936 women) were included in this study, with an average age of 37.38 years (SD: 13.27) and average SUA of 367.05 μmol/L (SD: 97.97) at baseline, respectively. Finally, 1078 participants developed obesity over the 9-year period. The prevalence of obesity was approximately 14.2% for high SUA level. In logistic regression analysis at baseline, we observed a positive association between SUA and risk of obesity: OR=1.84 (95% CI: 1.77 to 1.90) for per-SD increase in SUA. Considering repeated measures over 9 year for all participants in the GEE model, the per-SD OR was 1.85 (95% CI: 1.77 to 1.91) for SUA and the increased risk of obesity were greater for men (OR=1.45) and elderly participants (OR=1.01). In subgroup analyses by gender and age, we observed significant associations between SUA and obesity with higher risk in women (OR=2.35) and young participants (OR=1.87) when compared with men (OR=1.70) and elderly participants (OR=1.48). The SUA cut-off points for risk of obesity using ROC curves were approximately consistent with the international standard.

CONCLUSIONS

Our study observed higher SUA level was associated with increased risk of obesity. More high-quality research is needed to further support these findings.

Association between plasma uric acid and insulin resistance in type 2 diabetes: A Mendelian randomization analysis

OBJECTIVE

Circulating uric acid levels were associated with insulin resistance, but the causality is unclear. We aimed to investigate the association between plasma uric acid and insulin resistance in newly diagnosed type 2 diabetes (T2D).

METHODS

We enrolled 1,938 patients who underwent a 75-g oral glucose tolerance test. Insulin resistance was estimated based on the homeostatic model assessment index (HOMA2-IR) and the Matsuda index. Uric acid was measured in fasting plasma by uricase-peroxidase method. We genotyped single nucleotide polymorphisms (SNPs) that were recently identified as top hits in genome-wide association studies of uric acid levels. A weighted genetic risk score (wGRS) was calculated based on the associations between selected SNPs and uric acid levels.

RESULTS

The adjusted β coefficients for Ln-transformed Matsuda index and HOMA2-IR per 1 mg/dL uric acid increment were -0.070 (95%CI: -0.089, -0.052) and 0.057 (95%CI: 0.039, 0.075). These associations were more pronounced among women than men. In Mendelian randomization analysis, the wGRS raised uric acid by 0.225 mg/dL (95%CI: 0.138, 0.312) per SD increase of the score. However, no association was observed between the wGRS and insulin resistance indices whether in men or women.

CONCLUSIONS

Elevated plasma uric acid was associated with higher risk of insulin resistance, along with observation of gender difference in such association. However, our study does not support a causal role of plasma uric acid on insulin resistance among newly diagnosed T2D patients.

Serum uric acid and risk of incident hypercholesterolaemia and hypertriglyceridaemia in middle-aged and older Chinese: a 4-year prospective cohort study

PURPOSE

The aim was to investigate whether serum uric acid (SUA) was associated with incident hypercholesterolaemia and hypertriglyceridaemia in middle-aged and older Chinese.

METHODS

This prospective cohort study used data from the China Health and Retirement Longitudinal Study. A total of 6,063 participants were included, who were free of hypercholesterolaemia and hypertriglyceridaemia at baseline (2011) and were followed until 2015. Natural cubic spline models were conducted to investigate the dose-response association of SUA with incident hypercholesterolaemia and hypertriglyceridaemia. Moreover, SUA was categorized into four groups according to gender-specific quartiles. Log-binomial regression was performed to explore the association of SUA with hypercholesterolaemia and hypertriglyceridaemia, with the quartile 1 as a reference.

RESULTS

After full adjustment, we observed a positive linear dose-response relationship between SUA and hypercholesterolaemia and hypertriglyceridaemia. Compared with the quartile 1 of SUA, the adjusted risk ratios (95% confidence interval) of hypertriglyceridaemia were 1.15 (0.95-1.39), 1.23 (1.02-1.49) and 1.31 (1.08-1.59) for quartile 2-4 (p-value for trend = .004), respectively. Whereas, we failed to find SUA significantly associated with hypercholesterolaemia. Sex-stratified analyses indicated that the association of SUA with hypertriglyceridaemia was more evident in the female.

CONCLUSIONS

These findings suggest that SUA may be positively associated with incident hypertriglyceridaemia. KEY MESSAGES The natural cubic spline model showed a positive linear dose-response relationship between serum uric acid levels and hypertriglyceridaemia. Compared with the quartile 1 of SUA, the adjusted risk ratios (95% confidence interval) of hypertriglyceridaemia were 1.15 (0.95-1.39), 1.23 (1.02-1.49) and 1.31 (1.08-1.59) for quartile 2-4 (p-value for trend = .004), respectively. Sex-stratified analyses indicated that the association of serum uric acid with hypertriglyceridaemia was more evident in the female.

Obesity in Qatar: A Case-Control Study on the Identification of Associated Risk Factors

Obesity is an emerging public health problem in the Western world as well as in the Gulf region. Qatar, a tiny wealthy county, is among the top-ranked obese countries with a high obesity rate among its population. Compared to Qatar's severity of this health crisis, only a limited number of studies focused on the systematic identification of potential risk factors using multimodal datasets. This study aims to develop machine learning (ML) models to distinguish healthy from obese individuals and reveal potential risk factors associated with obesity in Qatar. We designed a case-control study focused on 500 Qatari subjects, comprising 250 obese and 250 healthy individuals- the later forming the control group. We obtained the most extensive collection of clinical measurements for the Qatari population from the Qatar Biobank (QBB) repertoire, including (i) Physio-clinical Biomarkers, (ii) Spirometry, (iii) VICORDER, (iv) DXA scan composition, and (v) DXA scan densitometry readings. We developed several machine learning (ML) models to distinguish healthy from obese individuals and applied multiple feature selection techniques to identify potential risk factors associated with obesity. The proposed ML model achieved over 90% accuracy, thereby outperforming the existing state of the art models. The outcome from the ablation study on multimodal clinical datasets revealed physio-clinical measurements as the most influential risk factors in distinguishing healthy versus obese subjects. Furthermore, multiple feature ranking techniques confirmed known obesity risk factors (c-peptide, insulin, albumin, uric acid) and identified potential risk factors linked to obesity-related comorbidities such as diabetes (e.g., HbA1c, glucose), liver function (e.g., alkaline phosphatase, gamma-glutamyl transferase), lipid profile (e.g., triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol), etc. Most of the DXA measurements (e.g., bone area, bone mineral composition, bone mineral density, etc.) were significantly (p-value < 0.05) higher in the obese group. Overall, the net effect of hypothesized protective factors of obesity on bone mass seems to have surpassed the hypothesized harmful factors. All the identified factors warrant further investigation in a clinical setup to understand their role in obesity.

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.

The relationship between elevated serum uric acid and arterial stiffness in a healthy population

OBJECTIVE

This study aims to investigate the relationship between serum uric acid and arterial stiffness in a healthy population.

METHODS

Among the 979 participants, baPWV was non-invasively measured, the circulating levels of uric acid were tested, and the uric acid polymorphisms (rs2231142 and rs11722228) were genotyped. Then, the Mendelian randomization method was employed to test the relationship between serum uric acid and arterial stiffness in a healthy population.

RESULTS

After adjusting for age, gender, antihypertensive medication, body mass index, waist-to-hip ratio, urea nitrogen, creatinine and diabetic mellitus, there was a significant allelic difference in uric acid levels for each genotype (P < 0.0001 for rs2231142; P = 0.007 for rs11722228). However, there were no differences on the potential confounders between the genotypes of rs2231142 and rs11722228 (P > 0.05). The baPWV was significantly associated with circulating levels of uric acid after adjusting for cardiovascular risk factors and other potential confounders (P = 0.002). However, neither the single polymorphism, nor the accumulation of culprit alleles was associated with baPWV (P = 0.92 for rs2231142; P = 0.60 for rs11722228; P for trend = 0.77 for the combined analysis of culprit alleles).

CONCLUSION

These results do not support the causal role of circulating levels of uric acid in the development of arterial stiffness.

Mendelian randomization study of serum uric acid levels and diabetes risk: evidence from the Dongfeng-Tongji cohort

OBJECTIVE

Limited Mendelian randomization (MR) studies have assessed the causal relationship between serum uric acid levels and diabetes risk. Here we investigated causality between the serum uric acid concentration and diabetes risk in Chinese population.

RESEARCH DESIGN AND METHODS

The observational analysis, based on the Dongfeng-Tongji prospective cohort (n=15 195) we tested the association of serum uric acid levels with incident diabetes risk. In the instrumental variable analysis, we examined the association of the genetic risk score (GRS) of serum uric acid with diabetes risk in case-control design (2539 cases and 4595 controls) via MR analysis.

RESULTS

During a mean (SD) follow-up of 4.5 (0.5) years, 1156 incident diabetes cases were identified. Compared with those in the lowest quintile of serum uric acid levels, the HRs of incident diabetes were 1.19 (95% CI 0.96 to 1.48), 1.12 (95% CI 0.90 to 1.40), 1.38 (95% CI 1.12 to 1.70), and 1.51 (95% CI 1.23 to 1.87) for Q2, Q3, Q4 and Q5, respectively (P-trend <0.001). The GRS was strongly associated with serum uric acid levels (β=0.17, 95% CI 0.15 to 0.19; P=2.81×10^-67). However, no significant association was observed between the GRS and diabetes risk (OR=1.01, 95 CI 0.95 to 1.06; P=0.75).

CONCLUSIONS

Even though serum uric acid levels were significantly associated with increased incident diabetes risk, the results did not provide evidence for a causal relationship between them.

Sex-Specific Differences in the Association of Metabolically Healthy Obesity With Hyperuricemia and a Network Perspective in Analyzing Factors Related to Hyperuricemia

BACKGROUND

Although obesity is a well-known risk factor for hyperuricemia, it remains unclear whether obese subjects with metabolically healthy status have a decreased the risk of hyperuricemia and whether sex modifies the association of metabolically healthy obesity (MHO) with hyperuricemia risk. We aimed to investigate the sex-specific association between MHO and other obesity phenotypes and hyperuricemia, and to use Bayesian networks to determine and visualize the interactions among hyperuricemia and its related factors.

METHODS

This study was conducted using data from the China Health and Nutrition Survey 2009. Hyperuricemia was defined as serum uric acid ≥ 420 μmol/L in men and ≥ 360 μmol/L in women according to the guidelines. Body mass index (BMI) was used to define normal weight, overweight, and obese status in subjects, and metabolic health state was defined by the Adult Treatment Panel (ATP)-III and Visceral Adiposity Index (VAI) criteria, respectively. Subjects were categorized into six phenotypes according to their metabolic health and BMI level status.

RESULTS

Of the 7,364 Chinese adult individuals included, the prevalence of hyperuricemia among MHO women was only 8.5% (95% CI 4.8 to 14.3%), but increased to 30.7% among MUO women, whereas the highest prevalence among men was found in the MUOW phenotype (39.4%, 95% CI 35.4 to 43.6%), compared to 15.4% for male subjects with MHO. After adjusting for confounders, the MHO phenotype was significantly associated with an increased risk of hyperuricemia compared with their MHNW counterparts in women (OR: 1.95, 95% CI: 1.02-3.74) whereas a significant association was not found in men (OR: 1.46, 95% CI: 0.8-2.68). A complex network structure was established by BNs and then used to find connections between hyperuricemia and its related factors, as well as their interrelationships. By using BN reasoning, the probability of having hyperuricemia was 0.076 among MHO men, while it reached 0.124 in MHO women.

CONCLUSIONS

In conclusion, our results demonstrated that the MHO phenotype was significantly associated with the risk of hyperuricemia only in women, not in men. This sex-specific differences in the association may suggest a favorable condition of MHO for Chinese men with respect to hyperuricemia risk, meanwhile more attention should be paid to the increased risk of hyperuricemia among MHO women.

The relationship between self-reported habitual snoring and hyperuricemia among Chinese urban adults: a cross-sectional study

BACKGROUND

Growing evidence suggests an independent relationship between habitual snoring and metabolic abnormalities. Currently, there are few data available on the association between snoring and hyperuricemia. Therefore, we evaluated the cross-sectional association between snoring and serum uric acid (UA) concentration and ascertain the effects of different snoring intensities on hyperuricemia among Chinese urban adults in Nanjing.

METHODS

We performed a cross-sectional study including 7699 participants (4197 men and 3502 women) from Nanjing Drum Tower Hospital aged ≥18 years over a two year (ie, 2016-2018) period. All participants were divided into four groups based on Snoring scores. Questionnaires, physical examinations and biochemical tests were conducted. Hyperuricemia was defined as levels of serum UA > 6.8 mg/dL in males and >6.0 mg/dL in females. We used a generalized linear model to investigate the association between snoring and serum UA concentration and logistic regression model to investigate the association between snoring and likelihood of having hyperuricemia in the age-, sex-adjusted model and in a multivariable model adjusting for demographic factor, plasma lipid profiles, blood glucose, blood pressure, smoking, and alcohol consumption.

RESULTS

The prevalence of hyperuricemia was 10.05% in the studied population and gradually increased across the snoring scores (P < 0.0001). We found that mild snoring, moderate, and severe snoring intensity were associated with high serum UA in the age-, sex-adjusted model and in a multivariable model adjusting for demographic and lifestyle/behavioral risk factors. The association was insisted with the addition of variables related to clinical outcomes such as diabetes, hypertension, and high-cholesterol levels.

CONCLUSIONS

Our results showed self-reported habitual snoring was associated with higher serum UA concentration among Chinese urban adults. Findings of this study indicate the significance of early detection and treatment of snoring to prevent hyperuricemia.

Epidemiology and prevalence of hyperuricemia among men and women in Chinese rural population: The Henan Rural Cohort Study

Objective: The aim of this study was to explore the latest prevalence of hyperuricemia and influencing factors in Chinese rural population.Methods: A survey was conducted from July 2015 to September 2017. A total of 38,855 (15,371 men and 23,484 women) subjects were recruited from the Henan Rural Cohort Study. Hyperuricemia was defined as a serum urate level of >7.0 mg/dL for men and >6.0 mg/dL for women. A meta-analysis of 19 studies that focused on hyperuricemia prevalence was performed to validate the result of the cross-sectional survey.Results: The crude and age-standardized prevalence of hyperuricemia was 10.24% and 12.60%, respectively. The prevalence of hyperuricemia decreased in men with increasing age, but the opposite trend was observed in women. The results of meta-analysis demonstrated that hyperuricemia prevalence in Chinese rural areas was 11.7%, consistent with the result of current survey. Multivariate logistic regression revealed that overweight or obesity, hypercholesterolemia, hypertriglyceridemia, hypoalphalipoproteinemia and high serum creatinine level could increase the risk of hyperuricemia, while high physical activity and fasting plasma glucose were associated with a lower risk of hyperuricemia in all participants.Conclusion: The latest prevalence of hyperuricemia is high in rural China and is associated with multiple factors, indicating that prevention and control strategies for hyperuricemia are needed urgently.

Association between resting heart rate and incident diabetes risk: a Mendelian randomization study

AIMS

Observational studies indicated that resting heart rate (RHR) was associated with diabetes mellitus (DM) risk; however, it remains unclear whether the association between RHR and DM is causal. We aimed to examine whether there was causal association of RHR with DM risk.

METHODS

A prospective study including 16,201 middle-aged and older Chinese (7031 males and 9170 females) derived from the Dongfeng-Tongji cohort was performed. Cox proportional hazard regression models were conducted to estimate the associations between RHR and incident DM risk. In 7481 participants, 65 single nucleotide polymorphisms related to RHR were genotyped. A genetic risk score (GRS) of RHR was calculated based on the RHR-associated variants. The causal associations of RHR with DM risk were investigated by Mendelian randomization analysis.

RESULTS

During a mean (SD) follow-up of 4.5 (0.5) years, 1110 diabetes were identified. Compared with the referential RHR group (≤ 60 beats per minute [bpm]), individuals with RHR > 80 bpm have a higher incident diabetes risk, with a hazard ratio of 1.40 (95% confidence interval [CI], 1.05-1.88). With per SD increase in the weighted genetic risk score, the resting heart rate increased by 0.71 bpm (95% CI 0.49-0.93). By using the GRS to estimate the unconfounded effect, we found that higher resting heart rate did not have a causal effect on diabetes risk (OR 1.00 [95% CI 0.95-1.05]).

CONCLUSIONS

The present study supported a positive but not a causal association of RHR with incident diabetes risk. More studies are needed to verify our findings.

The association of obesity and serum leptin levels with complete blood count and some serum biochemical parameters in Iranian overweight and obese individuals

Background: Obesity has been suggested to be well correlated with altered levels of complete blood count (CBC) parameters. In this study, the relationship of body mass index (BMI) and circulating leptin levels with CBC among obese and overweight adults was examined. Methods: CBC and biochemical parameters, WBC and hematological profiles, leptin levels, related factors to liver, and kidney and lipid profiles were measured among 184 obese and overweight people aged 18-60 years. Statistical analysis was performed using SPSS software. To assess the normality of data, the Kolmogorov-Smirnov test was used. Logarithmic transformation was performed for some variables with non-normal distribution. The association between 2 quantitative variables was measured using bivariate correlation (Pearson or Spearman). Pearson correlations and multiple regression analysis were performed to assess the correlation between variables. Simple and multiple regression analyses were performed to predict some variables. P- value <0.05 was considered significant. Results: Hematocrit, insulin, fasting blood sugar, uric acid, TG, LDL-C, VLDL-C, and ALT were positively correlated with BMI (p=0.041, r=0.149 for hematocrit; p≤0.001, r=0.520 for insulin; p≤0.001, r=0.363 for FBS; p≤0.001, r=0.309 for uric acid; p=0.015, r=0.189 for TG; p=0.030, r=161 for LDL-C; p=0.019, r=0.181 for VLDL-C; p≤0.001, r=0.299 for ALT), whereas urea and HDL-C were negatively correlated with BMI (p≤0.001, r=-0.368 for urea; p≤0.001, r=-0.297 for HDL-C). Moreover, LDL-C and insulin were positively correlated with leptin (P = 0.011, r = 0.194 for LDL-C, P = 0.013, r = 0.114 for insulin) and hematocrit, urea, creatinine, TG and VLDL-C were negatively correlated with leptin (p=0.040, r=-0.162 for hematocrit; p≤0.001, r=-0.305 for urea; p=0.007, r=-0.219 for creatinine; p=0.025, r=0.188 for TG; p=0.007, r=-0.218 for VLDL-C). Our analysis showed that white blood cell was positively correlated with leptin (β=17.36, p=0.048). Also, other CBC parameters had no significant correlations with BMI and leptin. Conclusion: According to the findings of this study, BMI had a negative association with urea and HDL-C, while BMI had a positive association with insulin, hematocrit, FBS, uric acid, TG, VLDL-C, LDL-C, and ALT. Furthermore, leptin had a negative association with hematocrit, creatinine, and urea, TG, VLDL-C and a positive association with LDL-C and insulin among the participants of this study.

Associations between serum uric acid and depression among middle-aged and elderly participants in China

Few studies have investigated the sex-related associations between serum uric acid and depression. This study aimed to explore the associations between serum uric acid and depression stratified by sex among middle-aged and elderly Chinese participants. Using the baseline data of the China health and retirement longitudinal study (CHARLS), a total of 10,522 participants aged 45 years and older were included in the final analysis. Depression symptoms were measured with the 10-term Center for Epidemiologic Studies Depression Scale (CES-D). A multivariable logistic regression model was performed to examine the associations between serum uric acid levels and depression, and the results are presented using odds ratios (ORs) and 95% confidence intervals (CIs). The prevalence of depression was 38% among middle-aged and elderly participants in China. In men, participants in the highest serum uric acid quartile had a decreased prevalence of depression relative to those in the lowest quartile (OR: 0.57; 95% CI: 0.41-0.81) after adjustment for potential confounders. However, there was no significant association between serum uric acid and depression among women. Participants with hyperuricemia were had no higher prevalence of depression relative to participants with normal serum uric acid level. Negative association between uric acid and depression was found in men, but not in women.

Serum Uric Acid Is Independently Associated with Risk of Obstructive Sleep Apnea-Hypopnea Syndrome in Chinese Patients with Type 2 Diabetes

Purpose

We aimed to investigate the association between serum uric acid (SUA) levels and obstructive sleep apnea-hypopnea syndrome (OSAHS) in patients with type 2 diabetes.

Methods

A cross-sectional study of 212 type 2 diabetes mellitus (T2DM) patients was conducted in Xiamen, China. All patients underwent polysomnography (PSG) recordings for OSAHS diagnosis. Patients were grouped according to the apnea-hypopnea index (AHI) as mild (5-14.9), moderate (15-29.9), and severe (≧30) OSAHS. Patients with AHI ≤ 4.9 served as the control group. Weight, body mass index (BMI), SUA, liver function, renal function, blood pressure, lipid profiles, and glycemic parameters were measured.

Results

A total of 158 patients (101 men and 57 women) with complete data were analyzed in this study. 127 patients were identified as OSAHS. Among the 127 patients with OSAHS, 56 (44.1%), 37 (29.1%), and 34 (26.8%) had mild, moderate, and severe OSAHS, respectively. Correlation analyses showed that the SUA level was significantly related to the apnea-hypopnea index (AHI) (r = 0.194, p = 0.016). The level of SUA was significantly higher among OSAHS patients compared to the control group (control group: 333.14 ± 80.52 μmol/L, mild group: 345.50 ± 90.27 μmol/L, moderate group: 363.59 ± 134.26 μmol/L, and severe group: 428.37 ± 123.58 μmol/L and p = 0.029). Multivariable logistic regression analyses showed that SUA was the independent risk factor for OSAHS (OR: 1.006, 95% CI: 1.001-1.011, p = 0.020).

Conclusions

The SUA level is significantly associated with the severity of OSAHS and should be controlled when managing OSAHS.

Obesity-Related Genetic Variants and Hyperuricemia Risk in Chinese Men

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

Prevalence of hyperuricemia and the relationship between serum uric acid and obesity: A study on Bangladeshi adults

Background and objectives

Recent studies have shown that hyperuricemia is commonly associated with dyslipidemia, cardiovascular diseases, hypertension and metabolic syndrome. Elevated serum uric acid has been demonstrated to be associated with obesity in the adult population in many countries; however, there is still a lack of evidence for the Bangladeshi population. The aims of this study were to evaluate the prevalence of hyperuricemia and determine the relationship between serum uric acid (SUA) and obesity among the Bangladeshi adults.

Methods

In this cross-sectional study, blood samples were collected from 260 adults (142 males and 118 females) and analyzed for SUA and lipid profile. All participants were categorized as underweight (n = 11), normal (n = 66), overweight (n = 120) and obese (n = 63) according to the body mass index (BMI) scale for the Asian population. Based on SUA concentration the participants were stratified into four quartiles (Q1: < 232 μmol/L, Q2: 232–291 μmol/L, Q3: 292–345 μmol/L and Q4: > 345 μmol/L).

Results

The mean age and BMI of the participants were 32.5 ± 13.3 years and 24.9 ± 3.8 kg/m², respectively. The average level of SUA was 294 ± 90 μmol/L with a significant difference between males and females (p < 0.001). Overall, the estimated prevalence of hyperuricemia was 9.3% with 8.4% in male and 10.2% in female participants. There were significant increases in the prevalence of obesity (17.4%, 22.2%, 28.6% and 31.8%, respectively, p < 0.01 for trend) across the SUA quartiles. A multiple logistic regression analysis revealed that SUA quartiles were independently associated with the presence of obesity (p < 0.01).

Conclusion

Present study indicates a significant positive relationship between SUA and obesity among the Bangladeshi adults. Therefore, routine measurement of SUA is recommended in obese individuals to prevent hyperuricemia and its related complications.

Association of ideal cardiovascular health metrics with serum uric acid, inflammation and atherogenic index of plasma: A population-based survey

BACKGROUND AND AIMS

We aimed to evaluate the link between inflammatory score [consisting of C-reactive protein (CRP) and white blood cells], serum uric acid (SUA) and atherogenic index of plasma (AIP) and the cardiovascular health (CVH) score.

METHODS

We used the cross-sectional National Health and Nutrition Examination Survey database. Statistical analyses accounted for the survey design and sample weights.

RESULTS

Overall, there were 23,004 participants (mean age = 47.2 years, 46.5% males). Participants with an ideal CVH level had the highest ratio of poverty to income (3.62%, p < 0.001), as well as lower levels of CRP, SUA and AIP (p < 0.001 for all comparisons). In adjusted linear regression, a significant negative association was observed between inflammatory score (β = -0.052, p < 0.001), SUA (β = -0.041, p < 0.001) and AIP (β = -0.039, p < 0.001) and CVH score, i.e. participants with a better (greater) CVH score had a lower inflammatory score. Results from adjusted logistic regression showed reduction in the likelihood of "high-risk atherosclerosis" (defined as AIP ≥0.21) [intermediate: odds ratio (OR) = 0.90, 95% confidence interval (CI):0.85-0.95, ideal: OR = 0.81, 95%CI: 0.74-0.88] and "high CVD risk" (defined as CRP ≥3 mg/l) [intermediate: OR = 0.86, 95%CI:0.73-0.98, ideal: OR = 0.82, 95%CI:0.69-0.95] across the categories of CVH.

CONCLUSIONS

Our findings highlight that CVH metrics were associated with inflammatory score, SUA and AIP. Furthermore, participants with a better CVH score had a lower CVD risk. These results reinforce the importance of implementing healthy behaviours as proposed by the American Heart Association. If confirmed in clinical trials, this knowledge may have implications for CVD prevention and management.

Folate, Vitamin B6 and Vitamin B12 Intake in Relation to Hyperuricemia

To assess the association between intake of folate, vitamin B6, and vitamin B12 with hyperuricemia (HU) among adults from the United States (US), we extracted relevant data from 24,975 US adults aged 20–85 years from the National Health and Nutrition Examination Survey (NHANES) in 2001–2014. All dietary intake was evaluated by 24-h dietary recalls. Multivariable logistic regression analysis was performed to explore the associations after adjustment for confounders. Compared to the lowest quintile (Q1), for males, adjusted odds ratios (ORs) of HU in Q2 to Q5 of folate (dietary folate equivalent, DFE) intake were 0.84 (95% CI, 0.73–0.96), 0.84 (0.73–0.97), 0.72 (0.62–0.84), and 0.64 (0.53–0.77), respectively (p for trend <0.0001). In females, adjusted ORs in Q2 to Q4 of folate (DFE) intake were 0.84 (95% CI, 0.71–0.99), 0.81 (0.68–0.96), and 0.82 (0.68–0.99), with a p for trend of 0.1475. Our findings indicated the intakes of total folate, folic acid, food folate, folate (DFE), vitamin B12, but not vitamin B6, were inversely related to the risk of HU in males. A lower risk of HU with higher intakes of total folate, food folate, and folate (DFE) was found in females, but with no association between intakes of folic acid, vitamin B6, B12, and the risk of HU for females.

Increased Serum Uric Acid over five years is a Risk Factor for Developing Fatty Liver

The prevalence of fatty liver disease (FLD) is increasing. To clarify risk factors for developing FLD, we analyzed a database from healthy Japanese adults who had annual medical check-ups in 2004 and reexamined in 2009. We used the fatty liver index (FLI) to classify participants as FLD (FLI ≥60), borderline FLD (30≤ FLI <60), and normal liver (FLI <30). Subjects with hepatitis B or C virus infection and subjects with FLD at the baseline were excluded. The cumulative incidence of FLD from normal liver and from borderline FLD over five years were 0.65% (52/8,025) and 12.9% (244/1,888), respectively. After multiple adjustments, higher serum uric acid (SUA) (OR:1.92; 95% CI:1.40–2.63) and increased SUA change (OR:3.734; 95% CI:2.57–5.42) became risk factors for developing FLD from normal liver, as well as younger age and higher body mass index. The risk factors for developing FLD from borderline FLD were similar. Not only higher baseline SUA but also increased SUA change became independent risks for developing FLD.

Association between Dietary Zinc Intake and Hyperuricemia among Adults in the United States

We aim to explore the associations between dietary zinc intake and hyperuricemia (HU) in United States (US) adults. 24,975 US adults aged 20 years or older from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2014 were stratified into quintiles based on zinc intake. All dietary intake measured through 24-h dietary recalls. Multivariable logistic regression analysis was performed to examine the association between zinc intake and HU after adjustment for possible confounders. For males, compared with respondents consuming less than 7.33 mg zinc daily, the adjusted odds ratios (ORs) were 0.83 (95% CI, 0.71, 0.97) among those consuming 10.26–13.54 mg zinc daily, 0.78 (95% CI, 0.63–0.96) among those consuming 18.50 mg or greater, and p for the trend was 0.0134. For females, compared with respondents consuming less than 5.38 mg zinc daily, the OR was 0.78 (95% CI, 0.63, 0.97) among those consuming 9.64–12.93 mg zinc daily, and p for the trend was 0.3024. Our findings indicated that dietary zinc intake is inversely associated with HU in US men and women, independent of some major confounding factors.

Dietary Magnesium Intake and Hyperuricemia among US Adults

To assess the association between dietary magnesium intake and hyperuricemia in United States (US) adults, we extracted 26,796 US adults aged 20–85 years from the National Health and Nutrition Examination Survey (NHANES) in 2001–2014. All dietary intake was measured through 24 h dietary recall method. Multivariable logistic regression analysis was performed to investigate the association between magnesium intake and hyperuricemia after adjusting for several important confounding variables. When compared to the lowest quintile (Q1), for male, adjusted odds ratios (ORs) of hyperuricemia in the second quintile (Q2) to the fifth quintile (Q5) of the magnesium intake were 0.83 (95% CI: 0.72–0.95), 0.74 (0.64–0.85), 0.78 (0.67–0.90), and 0.70 (0.58–0.84, p for trend = 0.0003), respectively. For female, OR was 0.75 (0.62–0.90) in the fourth quintile (Q4) (p for trend = 0.0242). As compared to Q4 of magnesium intake (contains recommended amount), the relative odds of hyperuricemia were increased by 1.29 times in Q1 (OR = 1.29, 1.11–1.50) in male. The ORs were 1.33 (1.11–1.61) in Q1, 1.27 (1.07–1.50) in Q2 in female. Our results indicated that increased magnesium intake was associated with decreased hyperuricemia risk. It also indicated the importance of recommended dietary allowance (RDA) of magnesium and the potential function of magnesium intake in the prevention of hyperuricemia.

The polymorphism rs671 at ALDH2 associated with serum uric acid levels in Chinese Han males: A genome-wide association study

Serum uric acid (SUA) levels are highly heritable and an increased SUA level is one of important risk factors for gout, diabetes, metabolic syndrome, and cardiovascular diseases. The genetic variants underlying SUA remains largely unexplored. The aim was to explore new genetic variants underlying SUA in Chinese Han. We performed a genome-wide association study of SUA levels in Han Chinese. The discovery set contained 1634 samples and subsequent replication was comprised of 1649 females and 1169 males. 2620 subjects were recruited in the detailed analysis of rs671, alcohol drinking and SUA. We found a genome-wide significant association between SUA level and the SNP rs671 at ALDH2 (P = 1.2 × 10^-10) in the merged data. In addition, we also replicated the signal from rs3733590 at SLC2A9 (P = 1.0 × 10^-10). In males, about 0.21% to 1.95% of the total variance for SUA can be explained by rs671 using linear regression models in four independent cohorts. Of those, 56.75% to 93.51% might be explained by altering alcohol consumption due to rs671. No statistical association of rs671 and SUA was observed in females (P = 0.409). Furthermore, we observed a causal relationship between alcohol consumption and SUA in males using rs671 as an instrumental variable (P = 5.1 × 10^-4). We replicated the previous findings in SLC2A9. Our evidence supported that rs671 was associated with SUA by affecting alcohol consumption in males. This finding strongly suggests a role for alcohol consumption in the development of hyperuricaemia and uric acid related traits.

Uric acid and cardiovascular risk: What genes can say

BACKGROUND

Although the relationship of elevated serum uric acid levels and cardiovascular disease has been established in a great number of studies, the causal relevance of this finding remains ambiguous. An approach to evaluate the causal relevance of biomarkers is to exploit the natural randomised allocation of allelic variation in genes affecting their level, also known as Mendelian randomisation.

AIM

The aim of this paper is to review the current literature regarding serum uric acid levels and cardiovascular and renal disease risk in Mendelian randomisation studies.

METHODS

PubMed and Scopus databases were searched to retrieve Mendelian studies regarding uric acid, hyperuricaemia and cardiovascular risk.

CONCLUSIONS

Genetic evidence based on conventional and novel Mendelian randomisation approaches suggest a modest, if any, causal effect of serum uric acid concentration on the development of cardiovascular disease, suggesting that further study of uric acid genes is needed in order to elucidate the relationship of serum uric acid levels and cardiovascular disease.

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

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

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

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