Association between hyperuricemia and metabolic syndrome: A cross-sectional study in Tibetan adults on the Tibetan plateau

Uric acid-induced cardiomyocytic polyamines' insufficience: a potential mechanism mediates cardiomyocytic injury

Introduction

Maintaining polyamines homeostasis is essential for cardiovascular health, whereas elevated uric acid levels are recognized as a significant risk factor for the onset and progression of cardiovascular diseases. However, the interaction between uric acid and the regulation of polyamine homeostasis has not been extensively investigated. The objective of this study was to investigate the influence of uric acid on cardiac polyamines regulation and elucidate the role of polyamines in uric acid induced cardiomyocytic injury.

Methods

The in vitro experiments utilized H9C2 cardiomyocytes, the hyperuricemic mouse model was established via potassium oxonate and hypoxanthine. Techniques included energy metabolomics, HPLC for polyamine quantification, qPCR, ELISA, immunofluorescence, and mitochondrial membrane potential assessment using JC-1 staining, MTT cell viability analysis.

Results

Uric acid treatment can alter ornithine metabolism in cardiomyocytes, revealed a potential of shifting it from the traditional ornithine cycle towards the polyamine cycle. Both ODC1 and SAT1 protein levels were up-regulated in hyperuricemic mice indicated a dysorder of polyamines homostasis. A downregulation tendency of spermidine and spermine levels were observed in cardiomyocytes under uric acid treatment. Notably, exogenous supplementation with spermidine or spermine effectively mitigated the uric acid-induced decline in cardiomyocyte viability and mitochondrial membrane potential.

Discussion

Uric acid disrupts polyamine homeostasis, leading to mitochondrial dysfunction and cardiomyocyte damage. Exogenous polyamine supplementation demonstrates therapeutic potential by preserving mitochondrial integrity. These findings unveil a potential mechanism underlying uric acid-induced cardiac injury and propose polyamine replenishment as a viable intervention strategy for hyperuricemia-related cardiovascular complications.

The association between serum uric acid levels and the cardiometabolic phenotype among healthcare workers of Tabriz University of Medical Sciences

Introduction

It is unclear whether hyperuricemia can be considered as an independent risk factor or just as a marker to represent the correlation between uric acid levels and other risk factors of MetS. In this work, we intend to study the correlation between serum uric acid (SUA) and the cardiometabolic phenotype among Tabriz University of Medical Science healthcare workers.

Methods

In this cross-sectional study, anthropometric measurements, serum fasting blood sugar (FBS), triglyceride (TG), cholesterol, high-density lipoprotein (HDL), liver enzymes, blood urea nitrogen (BUN), SUA, creatinine (Cr), and blood pressures of 1,451 healthcare workers were evaluated. MetS was diagnosed based on ATP III. We classified the participants into four cardiometabolic phenotypes: metabolically-healthy lean (MHL), metabolically-unhealthy lean (MUHL), metabolically-healthy obese (MHO), and metabolically-unhealthy obese (MUHO).

Results

MHL (26.6%) and MHO (65.8 %) had the highest prevalence rates in the first and second SUA categories, respectively (P≤0.001). Compared to the lowest SUA category, the odds of MHO and MUHO increased by 3.13 (95% CI 2.21-4.44) and 5.50 (95%CI 3.53-8.57) in the highest category, respectively. This trend was not observed regarding the association between MUHL and the SUA classification.

Conclusion

We propose using the easily-measured SUA level as a marker for early diagnosis of at-risk MUHL and MHO individuals to administer proper interventions. Further prospective studies are needed to identify the effects of SUA on the progression of MetS in various body-size subgroups.

Serum proteome profiling of plateau acclimatization in men using Olink proteomics approach

Plateau acclimatization involves adaptive changes in the body's neurohumoral regulation and metabolic processes due to hypoxic conditions at high altitudes. This study utilizes Olink targeted proteomics to analyze serum protein expression differences in Han Chinese individuals acclimatized for 6 months-1 year at 4500 and 5300 m altitudes, compared to those residing at sea level. The objective is to elucidate the proteins' roles in tissue and cellular adaptation to hypoxia. We identified 54 metabolism-related differentially expressed proteins (DEPs) in the serum of the high-altitude group versus the sea-level group, comprising 20 significantly upregulated and 34 downregulated proteins. Notably, 2 proteins were upregulated and 11 downregulated at both 4500 and 5300 m altitudes. The top three protein correlations among DEPs included CRKL with CA13, RNASE3 with NADK, and NADK with APEX1, alongside APLP1 with CTSH, CTSH with SOST, and CTSH with NT-proBNP in inverse correlations. KEGG enrichment analysis indicated significant DEP involvement in various metabolic pathways, particularly those associated with hypoxic cellular metabolism like glycolysis/gluconeogenesis and the HIF-1 signaling pathway. Correlation with clinical phenotypes showed positive associations of SOST, RNASE3, CA13, NADK, and CRKL with SaO2 and negative correlations with Hemoglobin and Hematocrit; ALDH1A1 positively correlated with Triglyceride; and SDC4 inversely correlated with Uric acid levels. This study provides insights into specific DEPs linked to metabolic adaptations in high-altitude acclimatized individuals, offering a foundation for understanding acclimatization mechanisms and potential therapeutic targets.

Prevalence and Association of Components of Metabolic Syndrome and Uric Acid among Commercial Drivers in South-West Nigeria

INTRODUCTION

Metabolic syndrome (MetS) is a complex cluster of metabolic abnormalities characterized by central obesity, dyslipidemia, hypertension, and impaired glucose metabolism. Emerging evidence suggests a potential link between uric acid levels and MetS, and commercial drivers are exposed to unique occupational hazards that may predispose them to MetS and hyperuricemia.

OBJECTIVES

The objective of this study was to determine the prevalence of MetS and its relationship with serum uric acid among commercial drivers in Ado-Ekiti, Nigeria.

MATERIALS AND METHODS

A cross-sectional study was conducted among commercial drivers in Ado-Ekiti. Relevant information was obtained with a questionnaire, and anthropometry and blood pressure were measured. Fasting plasma glucose and lipid profiles were determined by the standard protocol. MetS was determined with the harmonized criteria. Bivariate correlation and Chi-square were used to determine the relationship between serum uric acid and MetS and its components.

RESULTS

There were 106 participants with a median age (interquartile range) of 50 (11) years, with no difference between those with or without MetS. More than 70% of the participants drank alcohol and 75 (70.8%) participants had hyperuricemia. There was no significant correlation between serum uric acid and components of MetS. The prevalence of MetS among all the participants was 21.7% (23/106), with no difference among men with normal uric acid (25.8%) and those with elevated uric acid (20.0%), P = 0.509. Similarly, there was no statistical difference in the prevalence of the components of MetS between the two groups.

CONCLUSIONS

The prevalence of MetS among the commercial drivers was high, with no difference among men with or without hyperuricemia. Given the importance of this group of people, a system-level public health approach should be adopted to promote a healthy lifestyle to save the lives of the populace.

Prevalence and Associations Between Metabolic Syndrome Components and Hyperuricemia by Race: Findings From US Population, 2011-2020

OBJECTIVE

We explored the trend in prevalence of hyperuricemia and metabolic syndrome in US populations and investigated associations between components of metabolic syndrome and hyperuricemia by race.

METHODS

We analyzed data from the four most recent National Health and Nutrition Examination Survey (NHANES) cycles (2011 to March 2020), comprising 10,175 participants. Hyperuricemia is defined as serum urate >7.0 mg/dL (men) or >5.7 mg/dL (women), following the NHANES-III guideline. The definition of metabolic syndrome follows the National Cholesterol Education Program's Adult Treatment Panel III guideline. We estimated the prevalence of metabolic syndrome and hyperuricemia in each cycle and performed subgroup analyses with logistic regression to investigate the patterns of associated components of metabolic syndrome with hyperuricemia.

RESULTS

In the most recent cycle (2017 to March 2020), the prevalence of metabolic syndrome was 45.9% and that of hyperuricemia was 20.7%. Over the 2011 to 2020 period, a significant rise in metabolic syndrome prevalence was observed among Hispanic and Asian populations, and the prevalence of hyperuricemia has increased significantly only in the Hispanic population. After adjustment for confounding factors, patients with metabolic syndrome exhibited a higher hyperuricemia in women than in men. Elevated blood pressure was the strongest factor with hyperuricemia. The association was the weakest in the Asian population. Waist circumference was the only significant factor associated with hyperuricemia in the Asian population.

CONCLUSION

The prevalence of metabolic syndrome has an increasing pattern, but there was no specific decadal trend in prevalence of hyperuricemia. There is an ethnicity-specific association of metabolic syndrome and hyperuricemia, especially among Asians.

Serum uric acid and high-sensitivity C-reactive protein levels among people living with HIV on dolutegravir and ritonavir-boosted atazanavir-based antiretroviral therapy: a comparative cross-sectional study

Background

After the introduction of antiretroviral therapy, the care given to people living with HIV has become complicated by the appearance of comorbidities as a result of HIV and HAART toxicities, in which cardiovascular disease got the most attention. So, this study aimed to assess serum uric acid and high-sensitivity C-reactive protein levels among people living with HIV on dolutegravir (DTG) and ritonavir-boosted atazanavir (ATV/r)-based therapy.

Methods

An institutional-based comparative cross-sectional study was conducted from November 4, 2021, to January 4, 2022. An equal number of dolutegravir- and ritonavir-boosted atazanavir-treated patients (n = 86 each) were enrolled. A consecutive sampling method was used to select participants. Data were entered into Epidata version 4.6, exported to SPSS version 25.0, and analyzed using Chi-square, Student's t-test, Mann-Whitney U-test, and logistic regression. Statistical significance was set at p < 0.05.

Results

The prevalence of hyperuricemia and high-sensitivity C-reactive protein levels ≥2 mg/L were 46.5% (40/86) and 24.4% (21/86) in the DTG group, and 30.2% (26/86) and 44.2 (38/86) in the ATV/r group, respectively. When compared to ATV/r, a higher mean level of uric acid was found among DTG-based regimens (5.38 mg/dL). Duration of ART (AOR = 2, 95% CI: 1.2, 4.4) and DTG-based regimen (AOR = 1.9, 95% CI: 1.04, 3.8) were significant predictors of developing hyperuricemia. ATV/r-based regimen (AOR = 3, 95% CI: 1.5, 8.3) and high waist circumference (AOR = 2.5, 95% CI: 1, 3.5) were significantly associated with increased high-sensitivity C-reactive protein levels.

Conclusion

It is observed that DTG-based and ATV/r-based ART are associated with hyperuricemia and increased high-sensitivity C-reactive protein levels, respectively. Therefore, it is important to consider and evaluate serum uric acid and high-sensitivity C-reactive protein levels in patients taking DTG and ATV/r-based ART, as well as among those on HAART for years and with a higher waist circumference, so as to detect and prevent early the risk of having CVD.

Association of hyperuricemia with metabolic syndrome and its components in an adult population of Faisalabad, Pakistan

BACKGROUND AND AIMS

The rising prevalence of metabolic syndrome (MetS) is a matter of serious concern worldwide. Hyperuricemia has been observed as an independent risk factor in the development of MetS and each of its individual components in different populations. This study aims to determine the association of hyperuricemia with MetS and its individual components in a Pakistani cohort.

METHODS AND RESULTS

A cross-sectional study was performed in a public sector hospital in Faisalabad, Pakistan. Total 204 participants were studied along with their anthropometric measurements and blood sample analysis for clinically important parameters. MetS was defined according to the NCEP-criteria. Independent sample t-test, Binomial logistic regression and Linear regression analyses were used to determine the association between hyperuricemia and metabolic syndrome. The prevalence of MetS and hyperuricemia in our study was 42.6% and 31.9% respectively. As compared to the normo-uricemic group, the hyperuricemic group had a significantly higher systolic blood pressure, BMI and lower HDL-C level (p < 0.05). After adjusting for age, gender, BMI and LDL-C, hyperuricemia was observed to increase the risk of MetS, increased systolic blood pressure and reduce HDL-C respectively by 1.34, 1.23 and 1.20 folds respectively.

CONCLUSION

In this study, a significant association between hyperuricemia and metabolic syndrome, systolic hypertension, blood glucose and decreased HDL-C was observed.

The Cellular Genesis of Metabolic Syndrome and the Role of Anti-urate Drugs in Hyperuricemia Patients: A Systematic Review

Hyperuricemia results due to the underexcretion of uric acid through kidneys or overproduction due to either intake of purine-rich foods, a high caloric diet, or a decreased activity of purine recycler hypoxanthine-guanine phosphoribosyl transferase (HGPRT). Increased xanthine oxidoreductase (XOR) enzyme activity may contribute to hyperuricemia. Literature provides growing evidence that an independent component that contributes to the development of metabolic syndrome (MetS) and associated comorbidities is hyperuricemia. Thus, precise cellular mechanisms involved during MetS and related comorbidities in hyperuricemia, and the role of anti-urate medicines in these mechanisms require further investigations. We searched online libraries PubMed and Google Scholar for data collection. We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines for literature identification, selection, screening, and determining eligibility to produce unbiased meaningful outcomes. We applied quality assessment tools for the quality appraisal of the studies. And, outcomes were extracted from the selected studies, which revealed the relationship between hyperuricemia and MetS components by causing inflammation, endothelial dysfunction, oxidative stress, and endoplasmic reticulum stress. The selected studies reflected the role of xanthine oxide (XO) inhibitors beyond inhibition. This systematic review concluded that hyperuricemia independently causes inflammation, oxidative stress, endothelial damage, and endoplasmic reticulum stress in patients with hyperuricemia. These mechanisms provide a cellular basis for metabolic syndrome and related comorbidities. In this context, XO inhibitors and their beneficial effects go beyond XOR inhibition to ameliorate these pathological mechanisms.

Uric acid to HDL ratio: A marker for predicting incidence of metabolic syndrome in patients with type II diabetes

BACKGROUND AND AIM

Metabolic syndrome (MetS) refers to existence of a set of risk factors for developing cardiovascular disease and diabetes. Recently, uric acid to HDL ratio has attracted attention in predicting development of diabetes and incidence of metabolic syndrome in diabetic individuals. This study was performed to investigate UHR in patients with type II diabetes as a predicting factor for metabolic syndrome.

METHODS AND RESULTS

This descriptive-analytical study examined 300 patients with type II diabetes referring to diabetes clinic of Ali-Ibn Abi-Talib hospital, Rafsanjan city in 2021, selected through convenient sampling. Data were collected by a research-made checklist (including demographic, clinical and laboratory parameters) and analyzed by SPSS 24 and chi-square, Fisher exact test, independent paired t-test, one-way analysis of variance (ANOVA), Mann-Whitney U, and receiver operating characteristic (ROC). The findings revealed that 74.33 % (95 % CI: 69 to 79.18 %) of the patients had metabolic syndrome. Further, patients with metabolic syndrome demonstrated a significantly higher mean UHR ratio and triglyceride levels compared to their counterparts without the syndrome (p = 0.002 and p < 0.001, respectively). The ROC analysis identified a UHR threshold of 8.118 % with a sensitivity of 70.32 % and specificity of 55.08 % for diagnosing metabolic syndrome development in type II diabetes (AUC: 0.621, P = 0.001, 95%CI: 0.549-0.694).

CONCLUSION

The results of the present study revealed that the prevalence of metabolic syndrome was high in diabetic patients. UHR showed good sensitivity in the diagnosis of metabolic syndrome in type II diabetes. Thus, regular monitoring of laboratory tests is recommended in patients with diabetes.

[Analysis of Influencing Factors of Hyperuricemia in Tibetan Population in Nagqu City, Tibet]

Objective

To analyze the prevalence of hyperuricemia (HUA) among the Tibetan population in Nagqu City, Tibet and to uncover the relevant influencing factors.

Methods

From July 2020 to August 2021, 763 Tibetan natives from Bangor County (specifically Xinji Township and Jiaqiong Township) and Seni District (specificially Sexiong Township), Nagqu City were investigated by multi-stage cluster random sampling method and the prevalence of HUA was studied by retrospective analysis. Chi-square test and multiple logistic regression were used to analyze the influencing factors of HUA prevalence.

Results

The overall prevalence of HUA among the Tibetan population in the three townships of Nagqu City was 19.66% (150/763). In particular, the prevalence in men was 35.00%, while that in women was 8.58%, showing significant difference (P<0.05). According to the results of univariate analysis, there were significant differences in the distribution of sex, abnormal liver function, abnormal hemoglobin, hyperlipidemia, high level of low-density lipoprotein, hypertriglyceridemia, hypercholesterolemia, abnormal creatinine, hyperhomocysteinemia, obesity, and hypertension between HUA and non-HUA patients (P<0.05). Multiple logistic regression showed that female sex (odds ratio [OR]=0.195, 95% confidence interval [CI]: 0.120-0.315) was a protective factor for HUA, while abnormal liver function (OR=2.812, 95% CI: 1.685-4.692), abnormal creatinine (OR=7.374, 95% CI: 1.446-37.620), high level of low-density lipoprotein (OR=2.357, 95% CI: 1.011-5.492), and hyperlipidemia (OR=3.056, 95% CI: 1.886-4.951) were independent risk factors.

Conclusion

The prevalence of HUA is relatively high in Nagqu city and the prevalence of HUA is much higher in men than that in women. Male sex, abnormal liver function, abnormal creatinine, elevated low-density lipoprotein, and hyperlipidemia may be the risk factors for HUA in the local Tibetan population.

Distinctive biochemistry profiles associated with hyperuricemia between Tibetans and Hans in China

Purpose

We sought to identify distinct risk factors for hyperuricemia in native Tibetan and immigrant Han populations in Tibet, China.

Methods

Three cohorts of male participants aged between 20 and 40 years were enrolled in this study. Biochemical parameters including serum uric acid (UA), fasting plasma glucose, insulin, lactate dehydrogenase (LDH), thyroxin, blood cell count, aminotransferase, and lipid profiles were analyzed. The association of risk factors with UA levels was evaluated using a multivariable line regression model. The effect of UA level on the biochemical parameters between the Hans and Tibetans was evaluated by two-way ANOVA.

Results

The prevalence of hyperuricemia (≥420 μmol/L) was 24.8% (62/250) in the Hans, similar to 23.8% (29/136) in the Tibetans. In the regression analysis, the risk factors that were significantly associated with UA in Hans did not apply to Tibetans. Tibetans had higher fasting insulin (P<0.05) and LDH (P<0.01) levels, in contrast with lower levels of triglycerides (P<0.05), total cholesterol (P<0.01), and low-density lipoprotein-cholesterol (P<0.01) than Hans in normal UA populations. Biochemistry analysis revealed lower albumin levels (P<0.001) and higher levels of all aminotransaminase and especially alkaline phosphatase (P<0.01) in Tibetans than in Hans in both populations. Compared with Hans, Tibetans had lower serum levels of urea, creatinine, and electrolytes in the normal UA population, which were further exacerbated in the high UA population. Tibetans had comparable white blood cell counts as Hans in both normal and high UA populations. In contrast, the red blood cell count and hemoglobin concentration were much lower in Tibetans than in Hans under high UA conditions.

Conclusions

The distinctive biochemistry between Tibetans and Hans may underlie the different etiologies of hyperuricemia in Tibet, China.

Longitudinal study on blood and biochemical indexes of Tibetan and Han in high altitude area

Objective

This study aims to review the blood routine and biochemical indicators of the plateau population for three consecutive years, and analyze the impact of the plateau on these blood indicators of the Tibetan population and the Han immigrant population.

Method

These parameters were extracted from the Laboratory Department of Ali District People's Hospital in Tibet from January 2019 to December 2021, including blood routine, liver and kidney function, blood lipids, myocardial enzyme spectrum, and rheumatic factor indicators. Changes in these parameters were analyzed over 3 consecutive years according to inclusion and exclusion criteria.

Result

A total of 114 Tibetans and 93 Hans participated in the study. These parameters were significantly different between Tibetan and Han populations. Red blood cells (RBC), hemoglobin (HGB), hematocrit (HCT), mean hemoglobin content (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cells (WBC), lymphocytes (LYMPH) and monocytes (MONO) were significantly higher in Hans than Tibetans (p < 0.05). Biochemically, total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB), urea nitrogen (Urea), creatinine (Cr), uric acid (UA), glucose (GLU), triglycerides (TG) and creatine kinase isoenzyme (CKMB) were significantly higher in Hans than Tibetans; aspartate aminotransferase (AST), glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), antistreptolysin (ASO), and C-reactive protein (CRP) were significantly higher in Tibetans than Hans (p < 0.05). There were no obvious continuous upward or downward trend of the parameters for 3 consecutive years.

Conclusion

In high-altitude areas, Han immigrants have long-term stress changes compared with Tibetans. The main differences are reflected in the blood system, liver and kidney functions, etc., which provide basic data for further research on the health status of plateau populations.

Serum uric acid to high-density lipoprotein ratio as a novel indicator of inflammation is correlated with the presence and severity of metabolic syndrome: A large-scale study

INTRODUCTION

We investigated the association of serum uric acid to high-density lipoprotein ratio (UHR) with the presence and severity of metabolic syndrome (MetS) among MASHAD cohort participants.

METHODS

In this cross-sectional study, according to International Diabetes Federation criteria, the cohort participants were divided into MetS (+) and MetS (-) groups. MetS (+) were classified into Group 1 (those with 3 MetS criteria), Group 2 (those with 4 MetS criteria) and Group 3 (those with 5 MetS criteria). UHR was compared among the groups.

RESULTS

Data related to 9637 subjects including 3824 MetS (+) and 5813 MetS (-) were analysed. The mean UHR was significantly higher (p < .001) in the MetS (+) group compared with the MetS (-) group. UHR increased as the MetS severity increased (p < .001). ROC analysis revealed that UHR greater than 9.5% has 89.07% sensitivity and 77.03% specificity in differentiating MetS (-) from MetS (+) subjects.

CONCLUSION

Among MASHAD cohort study participants, a significant association between UHR and MetS was found. Furthermore, there is an increase in UHR as the severity of MetS increases. Registration number of MASHAD cohort study: 85134.

Possible correlated signaling pathways with chronic urate nephropathy: A review

Hyperuricemia nephropathy, also known as gouty nephropathy, refers to renal damage induced by hyperuricemia caused by excessive production of serum uric acid or low excretion of uric acid. the persistence of symptoms will lead to changes in renal tubular phenotype and accelerate the progress of renal fibrosis. The existence and progressive aggravation of symptoms will bring a heavy burden to patients, their families and society, affect their quality of life and reduce their well-being. With the increase of reports on hyperuricemia nephropathy, the importance of related signal pathways in the pathogenesis of hyperuricemia nephropathy is becoming more and more obvious, but most studies are limited to the upper and lower mediating relationship between 1 or 2 signal pathways. The research on the comprehensiveness of signal pathways and the breadth of crosstalk between signal pathways is limited. By synthesizing the research results of signal pathways related to hyperuricemia nephropathy in recent years, this paper will explore the specific mechanism of hyperuricemia nephropathy, and provide new ideas and methods for the treatment of hyperuricemia nephropathy based on a variety of signal pathway crosstalk and personal prospects.

Positive correlation between fatty liver index and hyperuricemia in hypertensive Chinese adults: a H-type hypertension registry study

Background

Few studies have examined the relationship between fatty liver index (FLI) and hyperuricemia (HUA). This study explores the relationship between FLI and HUA in hypertensive patients.

Methods

A total of 13,716 hypertensive subjects were included in the current study. FLI, a simple index calculated from triglycerides (TG), waist circumference (WC), body mass index (BMI), and γ -glutamyltransferase (GGT), was used as a useful predictor of nonalcoholic fatty liver disease (NAFLD) distribution. HUA was defined as serum uric acid ≥ 360 μmol/L for females and ≥ 420 μmol/L for males.

Results

The mean value of total FLI was 31.8 ± 25.1. Multiple logistic analyses revealed a significant positive correlation between FLI and HUA (OR, 1.78; 95% CI: 1.69-1.87). A subgroup analysis demonstrated that the correlation between FLI (< 30 vs. ≥ 30) and HUA was significant in both sexes (P for interaction = 0.006). Further analyses stratified by sex indicated a positive correlation between FLI and HUA prevalence among male and female subjects. However, the correlation between FLI and HUA was stronger in female subjects than in males (male: OR, 1.70; 95% CI: 1.58-1.83; female: 1.85; 95% CI: 1.73-1.98).

Conclusion

This study demonstrates a positive correlation between FLI and HUA in hypertensive adults, but stronger in females than males.

Association and Interaction between Heavy Metals and Hyperuricemia in a Taiwanese Population

The prevalence of hyperuricemia in Taiwan is high, and hyperuricemia has been associated with a risk of developing several diseases. Although the traditional risk factors for hyperuricemia are well known, the relationship between heavy metals and hyperuricemia is still undefined. Therefore, the aim of this study was to investigate the relationship between hyperuricemia and heavy metals. A total of 2447 participants (977 males and 1470 females) residing in southern Taiwan were enrolled, and levels of the following heavy metals were measured: lead in blood, and nickel, chromium, manganese, arsenic (As), copper, and cadmium in urine. Hyperuricemia was defined as a serum uric acid level greater than 7.0 mg/dL (416.5 μmol/L) in men and 6.0 mg/dL (357 μmol/L) in women. The participants were divided into two groups: those without hyperuricemia (n = 1821; 74.4%) and those with hyperuricemia (n = 626; 25.6%). Multivariate analysis showed that only high urine As (log per 1 μg/g creatinine; odds ratio, 1.965; 95% confidence interval, 1.449 to 2.664; p < 0.001), young age, male sex, high body mass index, high hemoglobin, high triglycerides, and low estimated glomerular filtration rate were significantly associated with hyperuricemia. In addition, the interactions between Pb × Cd (p = 0.010), Ni × Cu (p = 0.002), and Cr × Cd (p = 0.001) on hyperuricemia were statistically significant. Increasing levels of Pb and Cr yielded an increased prevalence of hyperuricemia, and the effect was progressively greater for increasing Cd. Moreover, increasing levels of Ni yielded an increased prevalence of hyperuricemia, and the effect was progressively greater for increasing Cu. In conclusion, our results show that high urine As is associated with hyperuricemia, and some interactions of heavy metals on hyperuricemia are noted. We also found that young age, male sex, high BMI, high hemoglobin, high triglycerides, and low eGFR were significantly associated with hyperuricemia.

Association between Dietary Patterns and Metabolic Syndrome and Modification Effect of Altitude: A Cohort Study of Tibetan Adults in China

Little is known about the longitudinal association between dietary patterns (DPs) and metabolic disorders in people living at high altitude areas, such as Tibetans. We constructed the first open cohort, with 1832 Tibetans, and collected data in 2018 and in 2022. The metabolic syndrome (MetS) prevalence was 30.1% (32.3% in men and 28.3% in women). Three different DPs were identified: modern DP (pulses, poultry, offal, and processed meat), urban DP (vegetables, refined grain, beef/mutton, and eggs), and pastoral DP (Tibetan cheese, tsamba, butter/milk tea, and desserts). Participants within the third tertile of the urban DP had a 3.42-fold (95% CI 1.65-7.10) higher risk of MetS than those with the first tertile. Modern DP was positively associated with elevated blood pressure (BP) and elevated triglycerides (TAG), while it was inversely associated with low HDL-C. The urban DP was associated with a higher risk of low HDL-C, but a lower risk of impaired fasting blood glucose (FBG). The pastoral DP was a risk factor for impaired FBG, but protective for central obesity and elevated BP. Associations of modern DP with elevated BP, and pastoral DP with low HDL-C, were modified by altitude. In conclusion, among Tibetan adults, DPs were associated with MetS and its components, and the associations were modified by altitude among Tibetans.