Effect of long-term administration of cross-sex hormone therapy on serum and urinary uric acid in transsexual persons

Association between sex hormones and gout: An analysis of the UK Biobank cohort

OBJECTIVES

To investigate the associations between sex hormones and gout.

METHODS

A total of 448,836 individuals free of gout at baseline were included from the UK Biobank. Cox regression models were used to estimate hazard ratios (HRs) for gout. Besides, we investigated the causal relationship between bioavailable testosterone (BAT) and gout using mendelian randomization (MR).

RESULTS

There were differential effects in different testosterone active states in gout. One-unit higher log-transformed total testosterone (TT) was associated with a 52 % [95 % CI, 0.39-0.58] lower risk of gout in males. In contrast, free testosterone (FT) and BAT were associated with a 74 % [95 % CI, 1.38-2.20] and a 78 % [95 % CI, 1.41-2.25] higher risk of gout in males respectively. For MR, the weighted median [OR, 1.70; 95 % CI, 1.14-2.56;] and inverse variance-weighted [OR, 1.25; 95 % CI, 0.96-1.62; P = 0.09] method revealed significant and approximately significant positive effect of genetic liability to BAT levels on the risk of gout respectively.

CONCLUSIONS

Sex hormones were potentially associated with gout. Notably, we were the first to explore different testosterone states on gout and found that FT and BAT may increase the risk of gout in males, which is opposite to TT. And the former are active states of androgens, may be more accurately reflect the association between androgens and gout.

The Prevalence of Hyperuricemia and the Association Between Hyperuricemia and Age in Patients with Psychiatric Disorders to a General Hospital: A Cross-Section Study

Purpose

In clinical work, it has been found that the prevalence of hyperuricemia (HUA) is significantly higher in younger patients with psychiatric disorders, but there are few studies in this area. The present study aims to evaluate the prevalence of HUA and the relationship between the HUA and age in hospitalized patients with psychiatric disorders in the real world, and to provide a theoretical basis for clinical staff to pay attention to the metabolic indicators of younger patients and for future related studies.

Methods

This is a cross-sectional evaluation of a cohort of 1761 patients with psychiatric disorders of hospitalized. The categories of disorders designed for study included: Depression, Bipolar disorder, Schizophrenia, Anxiety, Obsessive-Compulsive disorder, Acute and transient psychotic disorder, Dissociative(conversion) disorders, Conduct disorders and Tic disorders. In addition, based on age, the participants are stratified into three groups. The authors used Kruskal-Wallis tests, chi-square tests, and multiple linear logistic regression to verify the relationship between HUA and age among hospitalized patients with psychiatric disorders.

Results

Overall, the estimated prevalence of HUA was 35.4%. The prevalence of HUA was significantly higher in individuals with 17 years and under compared to those with 45 years and above (P < 0.001). After adjusting for confounders, the prevalence of HUA remained higher at 17 years and under than at 45 years and above. Bipolar disorder can lead to an increased prevalence of HUA (P<0.05).

Conclusion

The prevalence of HUA was higher in hospitalized patients with psychiatric disorders, and the prevalence was inversely proportional to age.

Associations of serum uric acid with hypertension status, stages, phenotypes and progressions among Chinese middle-aged and elderly

BACKGROUND AND AIMS

No consensus has been reached on the association between serum uric acid (SUA) and hypertension. This study aimed to investigate the associations between SUA and hypertension, including its status, stages, phenotypes and progressions, among middle-aged and older Chinese.

METHODS AND RESULTS

Data were obtained from the China Health and Retirement Longitudinal Study 2011-2015. Binary logistic regression was used to evaluate the association between SUA and hypertension status. Multinomial logistic regression was used to explore the associations of SUA with hypertension stages, phenotypes and hypertension status progressions. Models were adjusted for potential confounders and stratified by sex. A total of 7931 individuals aged ≥45 years were included, with 39.16 % of hypertension. Significant associations were found of SUA with stage2 and above hypertension (quartile 4 [Q4] vs quartile 1 [Q1]: odds ratio 1.78, 95 % confidence interval 1.31-2.42, P < 0.001), and systolic diastolic hypertension (SDH) (Q4 vs Q1: 1.53, 1.14-2.06, P = 0.005). In sex stratification, significant associations were found between SUA and stage2 and above hypertension and SDH only for men. Moreover, higher quartiles of baseline SUA showed increased risks of maintained hypertension from 2011 to 2015 (Q3 vs Q1: 1.23, 1.03-1.48, P = 0.024; Q4 vs Q1: 1.73, 1.43-2.10, P < 0.001).

CONCLUSION

Higher SUA was associated with hypertension and maintained hypertension among Chinese middle-aged and elderly. Sex-specific associations of SUA with hypertension stages and phenotypes were observed. Regular measurement of SUA in clinical practice may indicate hypertension and its progression, particularly among men.

A Gender-, Age-, and Weight Status-Specific Analysis of the High Prevalence of Hyperuricemia Among Chinese Children and Adolescents with Obesity

Objective

To explore the gender-, age-, and weight status-specific prevalence of hyperuricemia (HUA) and its associated risk factors among Chinese children and adolescents with obesity.

Methods

A total of 1329 children aged 2-17 years, who were diagnosed with obesity and hospitalized in our center from January 2016 to December 2022 were recruited. They were divided into mild obesity, moderate obesity, and severe obesity groups. HUA was defined as fasting serum uric acid level >420 μmol/L for boys and >360 μmol/L for girls. Multivariate logistic regression analyses were performed to identify risk factors for HUA.

Results

The highest proportion of hospitalized obese children was aged 10-13 years comprising 677 (50.9%) followed by those aged 6-9 years comprising 348 (26.2%) whereas the least proportion was aged 2-5 years comprising 76 (5.7%). The above differences in age distribution were still present in subgroup analyses according to weight status. Most hospitalized obese children were boys (64.7%), especially in the severe obesity group (75.0%). The overall estimated prevalence of HUA in obese children was 54.8%. It presented a gradual increase trend over the last 7 years, with more rapidly in boys than in girls. Subgroup analysis by weight status showed that the prevalence of HUA was higher in children with moderate obesity (64.3%) and severe obesity (64.2%) when compared with mild obesity (48.2%) (P all<0.01). Boys reached a relatively high HUA incidence level (≥60%) at age 12, which occurred about 2 years later than in girls (age 10). With 12 years as the cut-off point, a high prevalence of HUA (≥60%) was observed in both genders. Multivariable logistic regression analyses showed that boy (OR=2.844, 95% CI 2.024-3.998), age (OR=1.253, 95% CI 1.155-1.360), BMI-Z score (OR=2.132, 95% CI 1.438-3.162), fasting blood glucose (OR=0.907, 95% CI 0.860-0.956), phosphorus (OR=4.123, 95% CI 2.349-7.239), alkaline phosphatase (OR=1.002, 95% CI 1.001-1.004), creatinine (OR=1.067, 95% CI 1.037-1.098), urea nitrogen (OR=1.193, 95% CI 1.032-1.378), aspartate aminotransferase (OR=1.016, 95% CI 1.002-1.030), triglycerides (OR=1.339, 95% CI 1.075-1.667), and high-density lipoprotein cholesterol (OR=0.381, 95% CI 0.160-0.910) were independently associated with odds of HUA (P all<0.05).

Conclusion

The prevalence of HUA in Chinese obese children and adolescents is unexpectedly high. Childhood HUA was significantly associated with obesity. Gender and age differences were observed in the association between childhood obesity and HUA. Obese children aged ≥12 years should be focused on screening the risk of HUA.

Association of serum uric acid Levels with metabolic syndromes in Korean adolescents

Introduction

The study findings investigated uric acid reference values and their association with a cluster of cardiometabolic risk factors among adolescents using the Korea National Health and Nutrition Examination Survey (KNHANES).

Methods

A retrospective cross-sectional study was conducted using the KNHANES database from 2016 to 2018, involving a total of 2,462 participants aged between 10 and 18 years. Based on age- and sex-specific percentile curves for serum uric acid (SUA) levels from the KNHANES, we examined the correlation between cardiometabolic risk factors and serum uric acid levels.

Results

The percentile values of SUA varied with sex and age. In male subjects, SUA levels tended to increase from 10 to 14 years of age and plateaued after 14 years of age. Moreover, the overall uric acid level in females was found to be lower than that in males; the levels tended to increase at approximately 10 to 12 years old but were relatively consistent according to age. Mean uric acid levels increased according to obesity status in both males and females. However, correlation analysis revealed that SUA levels were associated with several metabolic risks even after adjusting for obesity. The detailed metabolic syndrome (MetS) components that were observed to be associated with an increase in uric acid levels were different between males and females, but overall, high uric acid levels increased MetS risk. Additionally, a significant increase in MetS-related odds ratio (OR) for components, including waist circumference (WC), triglyceride (TG) levels, and low high-density lipoprotein cholesterol (HDL-c), was observed. However, differences between sexes were apparent, with a more pronounced increase in OR based on SUA levels in girls.

Discussion

SUA levels were closely associated with MetS and its components, even in nonobese subjects. Therefore, high SUA levels in children and young adolescents should be closely monitored to prevent MetS.

Risk of gout in Taiwan Biobank participants pertaining to their sex and family history of gout among first-degree relatives

BACKGROUND

Family history of gout and sex are independently associated with gout. However, there is a paucity of research regarding the joint role of both factors in gout pathogenesis. Therefore, we assessed the independent and combined association of family history of gout and sex with gout.

METHODS

Our analysis included 132,311 Taiwan Biobank (TWB)-enrolled individuals comprising 21,159 gout cases and 111,152 controls. We subcategorized the family history of gout as (1) both siblings and parents had gout), (2) only parents had gout, and (3) only siblings had gout.

RESULTS

Generally, sex (men compared to women) and family history of gout were independently associated with a higher risk of gout. The odds ratio (OR); 95% confidence interval (CI) was 9.175; 8.801-9.566 for sex, and 2.306; 2.206-2.410 for family history. For the subcategories 'both siblings and had gout,' 'only parents had gout,' and 'only siblings had gout,' the odds ratios (ORs); 95% confidence intervals (CIs) were 4.944; 4.414-5.538, 2.041; 1.927-2.161, and 2.162; 2.012-2.323, respectively. The interaction between sex and family history was significant (p value = 0.0001). After stratification by sex, family history of gout remained significantly associated with a higher risk of gout in both sexes, even though the odds ratios were higher in men. For the subcategories 'both siblings and parents had gout,' 'only parent had gout,' and 'only siblings had gout,' the corresponding ORs; 95% CIs were 6.279; 5.243-7.520, 2.211; 2.062-2.371, and 2.148; 1.955-2.361 in men and 4.199; 3.566-4.945, 1.827; 1.640-2.035, and 2.093; 1.876-2.336 in women. After integrating sex and family history (reference: women with no family history), the highest risk of gout was observed in men who had at least one parent and sibling with a history of gout (OR; 95% CI 55.774; 46.360-67.101).

CONCLUSION

Sex and family history of gout were independently and interactively associated with gout. Sex-wise, men had a higher risk of gout than women. Family history was associated with a higher risk of gout in both sexes, but men had a higher risk. Notably, men having both siblings and parents with gout had the highest risk of gout.

Elevated serum uric acid is a risk factor for progression to prediabetes in Japanese women: A 5-year retrospective chort study

AIMS/INTRODUCTION

The association between serum uric acid (SUA) levels and prediabetes risk remains poorly understood. The aim of this longitudinal retrospective study was to evaluate the association between SUA levels and prediabetes progression in Japanese individuals through sex-specific analysis.

MATERIALS AND METHODS

We enrolled 20,743 participants (11,916 men and 8,827 women) who underwent annual medical health checkups in 2017 (baseline) and 2022. None of the participants had diabetes and prediabetes or were taking SUA-lowering medications at baseline. Participants were divided into four groups according to the quartiles of SUA levels at baseline. Multivariable-adjusted Cox regression analysis was conducted to examine the risk of prediabetes progression. In addition, multivariate restricted cubic spline analysis was conducted to investigate the dose-response risk.

RESULTS

In women, compared with the lowest SUA quartile (Q1) group, the adjusted hazard ratios (95% confidence intervals) of prediabetes in the Q2, Q3, and Q4 groups were 1.03 (0.86-1.25), 1.41 (1.18-1.68), and 1.55 (1.30-1.84), respectively. However, in men, no significant association in the risk of prediabetes was found across quartiles of SUA. Furthermore, in women, restricted cubic spline analysis revealed the dose-response relationship between SUA and progression to prediabetes.

CONCLUSIONS

The results indicate that elevated serum SUA levels might be positively and independently associated with an increased risk of progression to prediabetes in Japanese women.

Risk Factors for Hyperuricemia or Gout in Men and Women: The Circulatory Risk in Communities Study (CIRCS)

AIM

We aimed to examine sex-specific risk factors for hyperuricemia or gout in Japanese cohorts.

METHODS

We followed up 3,188 men (mean age, 55.6 years) and 6,346 women (mean age, 54.1 years) without hyperuricemia, gout, or elevated liver enzymes at baseline from 1986 to 1990 for a median of 14.6 years. The participants were considered as having hyperuricemia or gout if their serum uric acid levels were ≥ 7.0 mg/dL or they were receiving treatment for hyperuricemia or gout during annual health checkups. The sex-specific multivariable hazard ratios (HRs) of hyperuricemia or gout incidence were calculated after adjustment for smoking and drinking status, body mass index, hypertension, diabetes, hypercholesterolemia, and hypertriglyceridemia using the Cox proportional-hazard model.

RESULTS

During follow-up, 733 men and 355 women had hyperuricemia or gout. Among men, the multivariable HRs (95% confidence intervals) of hyperuricemia or gout were 1.23 (1.00-1.52) and 1.41 (1.13-1.75) for drinkers of ＜46 and ≥ 46 g ethanol/day, respectively, compared with non-drinkers; 1.00 (0.81-1.24) and 1.18 (0.93-1.50) for smokers of 1-19 and ≥ 20 cigarettes/day, respectively, compared with never smokers; and 1.41 (1.20-1.65) for hypertensive compared with non-hypertensive participants. The HRs for women were 1.02 (0.70-1.48), 1.66 (1.05-2.63), and 1.12 (0.88-1.42) for current drinkers, current smokers, and hypertensive participants, respectively. For both men and women, body mass index, diabetes, hypercholesterolemia, and hypertriglyceridemia were not associated with hyperuricemia or gout incidence.

CONCLUSIONS

Hypertension and alcohol drinking are risk factors for hyperuricemia or gout among men and smoking among women.

Effects of 24-hour oral estradiol-valerate administration on hormone levels in men and pre-menopausal women

In order to translate the findings from the vast animal literature on the effect of 17β-estradiol (E2) on brain and behavior to humans, a placebo-controlled pharmacological enhancement of E2 levels for at least 24 h is necessary. However, an exogenous increase in E2 for such a prolonged period might affect the endogenous secretion of other (neuroactive) hormones. Such effects would be of relevance for the interpretation of the effects of this pharmacological regimen on cognition and its neural correlates as well as be of basic scientific interest. We therefore administered a double dose of 12 mg of estradiol-valerate (E2V) to men and of 8 mg to naturally cycling women in their low-hormone phase, and assessed the concentration of two steroids critical to hormone regulation: follicle stimulating hormone (FSH) and luteinizing hormone (LH). We also assessed any changes in concentration of the neuroactive hormones progesterone (P4), testosterone (TST), dihydrotestosterone (DHT) and immune-like growth factor 1 (IGF-1). This regimen resulted in similar E2 levels in both sexes (saliva and serum). FSH and LH levels in both sexes were down-regulated to the same degree. P4 concentration decreased in both sexes only in serum but not saliva. TST and DHT levels dropped only in men whereas sex-hormone binding globulin was not affected. Finally, the concentration of IGF-1 decreased in both sexes. Based on previous studies on the effects of these neuroactive hormones, only the degree of downregulation of TST and DHT levels in men might have an impact on brain and behavior, which should be considered when interpreting the effects of the presented E2V regimes.

Associations of serum uric acid with cardiovascular disease risk factors: a retrospective cohort study in southeastern China

OBJECTIVE

To evaluate the associations between serum uric acid (SUA) levels and cardiovascular disease (CVD) risk factors, focusing on potential sex-specific differences.

DESIGN

A retrospective cohort study.

SETTING

A large community-based survey was conducted every two years from 2010 to 2018 in Hangzhou, Zhejiang Province, outheastern China.

PARTICIPANTS

6119 participants aged 40 years and above who underwent at least three times of physical examinations were enrolled.

METHODS

Participants were categorised into four groups (Q1-Q4) based on baseline SUA quartiles within the normal range, with hyperuricaemia (HUA) as the fifth group. The Q1 was the reference. By stratifying participants by gender, the relationships between SUA levels and systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG) and total cholesterol (TC) were investigated using linear regression models in the generalised estimating equation. Additionally, the associations of elevated SUA levels and HUA with hypertension, hyperglycaemia and dyslipidaemia were correspondingly examined using multivariate logistic regression models.

RESULTS

After adjusting for confounding variables, we found positive associations between SUA levels and SBP, DBP, FBG and TC in women, and with TC in men (p<0.01). Likewise, elevated SUA quartiles and HUA were linked to increased dyslipidaemia risk in both sexes, and increased hyperglycaemia risk only in women, with HRs (95% CI) of 1.64 (1.05 to 2.55) and 2.37 (1.47 to 3.81) in the Q4 and HUA group, respectively. Women with HUA had higher hypertension risk (HR=1.45, 95% CI 1.21 to 1.73), while no such association was observed in men. Stratified analyses revealed significant associations between elevated SUA levels and CVD risk factors in postmenopausal and non-obese women.

CONCLUSIONS

Elevated SUA levels increase the risk of dyslipidaemia in both sexes. SUA levels within normal range and HUA are positively associated with hyperglycaemia and hypertension in postmenopausal women, but not in men.

Relationship between serum uric acid and hypertension in the general US population aged 20 years and older: A cross-sectional study based on NHANES 2007 to 2016

The aim of this study was to investigate the association between serum uric acid (UA) levels and hypertension in American individuals 20 years of age and older. We used continuous cross-sectional surveys from the National Health and Nutrition Examination Survey in the United States from 2007 to 2016. Our selected population was adults aged 20 years and older in the United States. We examined the association between serum UA and risk of hypertension using weighted univariate logistic regression analysis, weighted multivariate logistic regression analysis, weighted subgroup analysis, and weighted restricted cubic spline analysis. Serum UA was significantly linked with hypertension in a multivariate logistic regression model adjusted for all variables (odds ratio [OR]: 1.22, 95% confidence interval [CI]: 1.15-1.28, P < .001). Furthermore, dividing serum UA into quartiles (Q) revealed an association between elevated serum UA and increased risk of hypertension [Q1 = (OR: 1.00), Q2 = (OR: 1.13, 95% CI: 0.95-1.37, P = .159), Q3 = OR: 1.30, 95% CI: 1.10-1.52, P = .002), Q4 = OR: 1.94, 95% CI: 1.58-2.38, P = .161). Additionally, we conducted subgroup analyses for age, sex, race, education, marital status, diabetes status, smoking, and alcohol use and discovered that these factors had a moderating effect on serum UA and hypertension (P < .05). Last but not least, we looked into the nonlinear link between serum UA and hypertension using weighted restricted cubic splines and discovered that there was no such relationship. The segmental effect of serum UA and hypertension, with an inflection point of 5.079 (mg/dL), was discovered in our gender-stratified study. And in analyses stratified by race and marital status, we similarly found a dose-response relationship between UA and hypertension among Hispanics and unmarried people. Our study showed a positive correlation between serum UA and hypertension.

An analysis of the associations of high-sensitivity C-reactive protein and uric acid with metabolic syndrome components in Korean adults by sex: a cross-sectional study using the Korea national health and nutrition examination survey 2016-2018

BACKGROUND

Low-grade inflammation plays a role in the pathogenesis of metabolic syndrome (MetS), and measuring levels of inflammatory molecules, such as high-sensitivity C-reactive protein (hs-CRP), may indicate Mets progression. Serum uric acid (SUA) has also been identified as an independent risk factor for MetS. This study aimed to investigate the association between MetS components and levels of serum hs-CRP and SUA using representative and reliable data for the Korean population.

METHODS

This study used the data of the Korea National Health and Nutrition Examination Survey 2016-2018, a cross-sectional and nationally representative survey performed by the Korean Centers for Disease Control and Prevention.

RESULTS

We analysed the data of 13,454 individuals. High hs-CRP levels were observed in 1,164 (8.7%) subjects while 3,296 (24.5%) subjects had high SUA levels. Moreover, hs-CRP was negatively correlated with serum high-density lipoprotein (HDL) (OR, 1.703; 95% CI, 1.431-2.027). When stratified by sex, this trend remained, but the correlation was stronger in women than in men. Furthermore, high SUA levels were significantly associated with hypertension (HTN) (OR, 1.399; 95% CI, 1.210-1.616), hypertriglyceridemia (OR, 1.735; 95% CI, 1.486-2.026), and low HDL (OR, 1.257; 95% CI, 1.106-1.429), but not with diabetes mellitus (DM) (OR, 0.478; 95% CI, 0.382-0.597). When grouped by sex, this trend remained, however, all MetS components were found to be more prevalent in women with high SUA.

CONCLUSIONS

Our findings showed that low HDL was more prevalent in subjects with high hs-CRP, and high SUA levels were observed in subjects with HTN, hypertriglyceridemia, and low HDL. However, the prevalence of high SUA was lower in diabetic subjects.

Association between Hyperuricemia and Hearing Impairment: Results from the Korean National Health and Nutrition Examination Survey

Background and Objectives: Hyperuricemia is associated with a variety of comorbidities. The objective of this study was to investigate the association between hyperuricemia and hearing impairment in Korean adults. Materials and Methods: Audiometric and laboratory test data from the 2019 to 2020 Korean National Health and Nutrition Examination Survey (KNHANES) were used for analysis. Hearing impairment was defined as a pure-tone average (0.5, 1, 2, 4 kHz) threshold level ≥ 41 decibels. The definition of hyperuricemia was different for males and females: >7 mg/dL for males vs. >6 mg/dL for females. Results: A total of 4857 (weight n = 17,990,725) subjects were analyzed. The mean age was 56.8 years old. The weighted prevalence was 12.1% for hyperuricemia and 2.5% for gout. The prevalence of hearing impairment was 13.4%. In the univariable analysis, hyperuricemia was significantly associated with hearing impairment. However, the diagnosis of gout was not associated with hearing impairment. In the multivariable analysis, hyperuricemia (odds ratios (OR): 1.41, 95% confidence interval [CI]: 1.03-1.92, p = 0.030) was associated with hearing impairment along with age (OR: 1.12, 95% CI: 1.10-1.14, p < 0.001), female sex (OR: 0.43, 95% CI: 0.34-0.64, p < 0.001), education (OR: 0.43, 95% CI: 0.30-0.63, p = 0.001), and occupational noise exposure (OR: 1.67, 95% CI: 1.25-2.22, p = 0.001). In the subgroup analysis, hyperuricemia was associated with hearing impairment in females (OR: 1.59, 95% CI: 1.02-2.48, p = 0.041) and the elderly aged 60 years or more (OR: 1.45, 95% CI: 1.05-1.99, p = 0.023). Conclusions: Hyperuricemia was independently associated with hearing impairment, especially in females and the elderly aged 60 years or more.

The association between serum uric acid and creatine phosphokinase in the general population: NHANES 2015-2018

BACKGROUND

The association between serum creatine phosphokinase (CPK), a standard biochemical measure of acute myocardial infarction, and serum uric acid (sUA) has not been studied. This study aimed to determine the association between sUA and CPK in the general population of the US.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) 2015-2018 were used, including a total of 8,431 subjects aged ≥ 30 years. Weighted multiple regression analysis was used to estimate the independent relationship between sUA and CPK. Fitted smoothing curves and weighted generalized additive models were also performed.

RESULTS

We found a positive relationship between sUA and CPK after adjusting for potential confounders. In subgroup analyses stratified by sex and race/ethnicity, sUA was positively correlated with CPK in each subgroup. The association between sUA and CPK followed an inverted U-shaped curve in females (turning point: sUA = 428.3 μmol/L).

CONCLUSIONS

Our study suggested that sUA level was positively correlated with CPK in the general population of the US. However, CPK increased with sUA until the turning point (sUA = 428.3 μmol/L) in females. Fundamental research and large sample prospective studies are needed to determine the exact mechanism of the association between sUA and CPK.

Association between serum uric acid and measures of adiposity in Chinese adults: a cross-sectional study

OBJECTIVE

The purposes of the study were to investigate the detailed association of serum uric acid (SUA) with visceral fat area (VFA) and body fat percentage (BFP) as calculated by bioelectrical impedance analysis (BIA) and build non-invasive diagnosis models of hyperuricaemia by combining obesity-related indicators, age and sex.

METHOD

A total of 19 343 adults were included. Multivariable regression analysis models were employed to analyse the association of SUA with VFA and BFP. Receiver operating characteristic curves were generated to diagnose hyperuricaemia in adults.

RESULTS

After fully adjusting for covariates, SUA was positively associated with VFA, BFP and body mass index (BMI) with βs of 0.447, 2.522 and 4.630 (95% CI= (0.412 to 0.482), (2.321 to 2.723) and (4.266 to 4.994)). After stratification by gender, this association persists (p<0.001). Fitted smoothing curves identified non-linear relationships between SUA and both VFA and BMI after full adjustment in males (inflection points: 93.9 cm² and 30.9 kg/m²). A non-linear relationship also exists between SUA and BFP in females (inflection point: 34.5%). A combined model incorporating BFP, BMI, age and sex exhibited the best ability to diagnose hyperuricaemia (AUC (area under the curve) =0.805, specificity=0.602, sensitivity=0.878). For normal-weight and lean populations, individuals with hyperuricaemia tended to have higher levels of VFA and BFP in females and males, respectively (p<0.001). The combination of VFA, BFP, BMI, age and sex exhibited the best ability to diagnose hyperuricaemia in normal-weight and lean populations (AUC=0.803, specificity=0.671, sensitivity=0.836).

CONCLUSION

VFA and BFP are independent factors associated with SUA. In males, SUA shows a non-linear relationship with VFA and BMI. In females, SUA and BFP exhibit a non-linear relationship. In normal-weight and lean individuals, the accumulation of VFA and BFP may be involved in hyperuricaemia. VFA and BFP were helpful in diagnosing hyperuricaemia in adults, especially for normal-weight and lean populations.

Association between breast nodules, anxiety, depression and metabolic risk factors in a Chinese cohort

Background

The relationship between anxiety, depression, and metabolic parameters and the incidence of breast nodules is unclear. This study aims to investigate the association between female breast nodules and anxiety, depression and metabolic factors.

Methods

This cross-sectional study recruited 857 individuals with biological indicators and breast ultrasound data from the Daping hospital from April 2021 to February 2022. Serum samples were used to measure fasting blood glucose, uric acid, triglycerides, total cholesterol, urea nitrogen, alanine transaminase, aspartate transaminase, albumin, high-density lipoprotein, low-density lipoprotein. Self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to assess the level of anxiety and depression.

Result

The positive rate of breast nodules in women aged 40 to 49 years old was significantly higher than that of other age women. The proportion of participants aged 40-49 years old in the group with breast nodules was significantly higher than that in the group without breast nodules (34.6% vs. 16.9%, p<0.001). Breast nodules in postmenopausal women were significantly lower than those in premenopausal women (26.4% vs. 73.6%, p = 0.026). The SAS scores of women with breast nodules were higher than those of the no-nodules group (40.99 ± 8.45 vs. 38.94 ± 6.89, p<0.001), same as the SDS scores (41.97 ± 10.33 vs. 38.91 ± 7.60, p < 0.001). The number of women suffering from anxiety in the group of breast nodules was significantly higher than that in control (13.8% vs. 4.5%, p < 0.001), and the number of depression in the group of breast nodules was also significantly higher than that of in control (14.4% vs. 4.5%, p < 0.001). Women with breast nodules showed a slightly lower uric acid level than those without breast nodules (290.11 ± 65.32 vs. 301.43 ± 65.93 umol/L, p = 0.016). Multivariable logistic regression analysis showed that age, menopausal status, anxiety and depression status were significantly associated with the presence of breast nodules, but there was no significant difference in uric acid.

Conclusion

Our findings offer insight into the occurrence of depression and anxiety in the breast nodules of Chinese women. Anxiety and depression status, age and menopausal status may be the independent risk factors for the occurrence of breast nodules.

Combining body mass index and waist height ratio to assess the relationship between obesity and serum uric acid levels in adolescents

Background

The study aims to explore the relationship between obesity and serum uric acid in adolescents by combining body mass index and waist height ratio.

Methods

475 adolescents in our study were classified as normal weight without central obesity (NW), normal weight but central obesity (NWCO), overweight or obesity without central obesity (OB) and overweight or obesity with central obesity (OBCO). Odds ratios (OR) and 95% confidence intervals (CI) for hyperuricemia were calculated using a logistic regression model. The dose-response association between obesity indicators and serum uric acid were explored by restricted cubic spline model.

Results

The highest serum uric acid level and the OR for hyperuricemia were found in the OBCO group, regardless of sex. After controlling for waist height ratio, the risk of hyperuricemia increased with increasing body mass index in boys and girls. The restricted cubic spline model showed that boys had higher ORs for hyperuricemia at the 25th and 75th percentiles of body mass index than for waist height ratio and girls had a higher OR for hyperuricemia than waist height ratio at the 25th percentile of body mass index.

Conclusions

Hyperuricemia in adolescence was not only associated with the overweight or obesity in BMI, but with the combination of overweight or obesity in BMI and central obesity in WHtR. However, in boys and girls, the increased risk of hyperuricemia associated with elevated body mass index was significantly better than that of waist height ratio.

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.

Elevated serum uric acid is associated with infertility in women living in America

Excessive uric acid levels may affect several organs and systems in the body. There is limited evidence of the effects of high serum uric acid levels on the female reproductive system. This study used the National Health and Nutrition Examination Survey (NHANES) database to explore the relationship between serum uric acid and female infertility. This cross-sectional study included a total of 2197 eligible subjects using data from NHANES 2013-March 2020 pre-pandemic data. Self-reported infertility (ever experiencing an inability to conceive after 12 months of trying to become pregnant) was the main outcome. Logistic regression models and restricted cubic spline were used to analyze the relationship between serum uric acid and female infertility, and stratified analysis was carried out. A total of 295 women self-reported infertility (13.43%). The median uric acid level for all study subjects was 4.4 mg/dL (interquartile range [IQR]: 3.7, 5.1). Serum uric acid levels were higher in the infertility group than in the control group (4.7 mg/dL [IQR: 4.0, 5.3] vs. 4.4 mg/dL [IQR: 3.7, 5.1], P < 0.001). After adjusting for age, race, marital status, smoking, alcohol, history of pregnancy, history of diabetes, history of hypertension, fasting glucose, total cholesterol, creatinine in refrigerated serum, low-density lipoprotein cholesterol, direct high-density lipoprotein cholesterol, glycohemoglobin, and body mass index confounders, women with serum uric acid levels at Q3 (4.4-5.1 mg/dL) had a 73% (odds ratio [OR] = 1.73, 95% confidence interval [CI] 1.18, 2.54, P = 0.005) higher risk of infertility, and women with uric acid levels at Q4 (5.1-18.0 mg/dL) had an 83% (OR = 1.83, 95% CI 1.22, 2.75, P = 0.003) increased risk of infertility compared to women at Q1 (1.6-3.7 mg/dL). The restricted cubic spline also showed that when serum uric acid levels exceeded the reference value, the risk of infertility gradually increased. We also performed a sensitivity analysis based on the complete dataset and found that the results were robust. Higher serum uric acid levels were significantly associated with an increased risk of female infertility. Women planning a pregnancy should have increased serum uric acid monitoring.

Joint Effect of Multiple Metals on Hyperuricemia and Their Interaction with Obesity: A Community-Based Cross-Sectional Study in China

Metal exposures have been inconsistently related to the risk of hyperuricemia, and limited research has investigated the interaction between obesity and metals in hyperuricemia. To explore their associations and interaction effects, 3300 participants were enrolled from 11 districts within 1 province in China, and the blood concentrations of 13 metals were measured to assess internal exposure. Multivariable logistic regression, restricted cubic spline (RCS), Bayesian kernel machine regression (BKMR), and interaction analysis were applied in the single- and multi-metal models. In single-metal models, five metals (V, Cr, Mn, Co, and Zn) were positively associated with hyperuricemia in males, but V was negatively associated with hyperuricemia in females. Following the multi-metal logistic regression, the multivariate-adjusted odds ratios (95% confidence intervals) of hyperuricemia were 1.7 (1.18, 2.45) for Cr and 1.76 (1.26, 2.46) for Co in males, and 0.68 (0.47, 0.99) for V in females. For V and Co, RCS models revealed wavy and inverted V-shaped negative associations with female hyperuricemia risk. The BKMR models showed a significant joint effect of multiple metals on hyperuricemia when the concentrations of five metals were at or above their 55th percentile compared to their median values, and V, Cr, Mn, and Co were major contributors to the combined effect. A potential interaction between Cr and obesity and Zn and obesity in increasing the risk of hyperuricemia was observed. Our results suggest that higher levels of Cr and Co may increase male hyperuricemia risk, while higher levels of V may decrease female hyperuricemia risk. Therefore, the management of metal exposure in the environment and diet should be improved to prevent hyperuricemia.

The Effect of Gender-Affirming Hormone Therapy on Measures of Kidney Function: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Gender-affirming hormone therapy modifies body composition and lean muscle mass in transgender persons. We sought to characterize the change in serum creatinine, other kidney function biomarkers, and GFR in transgender persons initiating masculinizing and feminizing gender-affirming hormone therapy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We searched PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov from inception to September 16, 2020 for randomized controlled trials, observational studies, and case series that evaluated the change in serum creatinine, other kidney function biomarkers, and GFR before and after the initiation of gender-affirming hormone therapy in adult transgender persons. Two reviewers independently screened and abstracted data, and disagreements were resolved by a third reviewer. A random effects meta-analysis was performed to determine the change in outcomes over follow-up of 3, 6, and 12 months.

RESULTS

Of the 4758 eligible studies, 26 met the inclusion criteria, including nine studies that recruited 488 transgender men and 593 women in which data were meta-analyzed. There was heterogeneity in study design, populations, gender-affirming hormone therapy routes, and dosing. At 12 months after initiating gender-affirming hormone therapy, serum creatinine increased by 0.15 mg/dl (95% confidence interval, 0.00 to 0.29) in 370 transgender men and decreased by -0.05 mg/dl (95% confidence interval, -0.16 to 0.05) in 361 transgender women. No study reported the effect of gender-affirming hormone therapy on albuminuria, proteinuria, cystatin C, or measured GFR.

CONCLUSIONS

Gender-affirming hormone therapy increases serum creatinine in transgender men and does not affect serum creatinine in transgender women. The effect on gender-affirming hormone therapy on other kidney function biomarkers and measured GFR is unknown.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Change in Kidney Function Biomarkers in Transgender Persons on Gender Affirmation Hormone Therapy-A Systematic Review and Meta-Analysis, CRD42020214248.

Genetic Basis of the Epidemiological Features and Clinical Significance of Renal Hypouricemia

A genetic defect in urate transporter 1 (URAT1) is the major cause of renal hypouricemia (RHUC). Although RHUC is detected using a serum uric acid (UA) concentration <2.0 mg/dL, the relationship between the genetic state of URAT1 and serum UA concentration is not clear. Homozygosity and compound heterozygosity with respect to mutant URAT1 alleles are associated with a serum UA concentration of <1.0 mg/dL and are present at a prevalence of ~0.1% in Japan. In heterozygous individuals, the prevalence of a serum UA of 1.1−2.0 mg/dL is much higher in women than in men. The frequency of mutant URAT1 alleles is as high as 3% in the general Japanese population. The expansion of a specific mutant URAT1 allele derived from a single mutant gene that occurred in ancient times is reflected in modern Japan at a high frequency. Similar findings were reported in Roma populations in Europe. These phenomena are thought to reflect the ancient migration history of each ethnic group (founder effects). Exercise-induced acute kidney injury (EI-AKI) is mostly observed in individuals with homozygous/compound heterozygous URAT1 mutation, and laboratory experiments suggested that a high UA load on the renal tubules is a plausible mechanism for EI-AKI.

Lowering and Raising Serum Urate Levels: Off-Label Effects of Commonly Used Medications

Drug-induced hyperuricemia and gout present an increasingly prevalent problem in clinical practice. Herein, we review the urate-lowering or urate-raising effects of commonly used agents. We performed a PubMed search using the terms gout, urate, and medication, along with the specific agents/classes described herein. Reports were reviewed until 2022, and original studies were considered if they primarily or secondarily reported the effects of 1 or more drugs on serum urate level. Previous reviews were assessed for references to additional studies that described urate-altering effects of medications. Urate-changing drugs are summarized regarding their magnitude of effect, mechanism of action, and clinical significance. Potentially urate-lowering drugs include angiotensin II receptor blockers, calcium channel blockers, high-dose aspirin and salicylates, some nonsalicylate nonsteroidal anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, sodium-glucose cotransporter 2 inhibitors, statins, and fenofibrate. Potentially urate-increasing drugs discussed include diuretics, β-blockers, insulin, pyrazinamide, ethambutol, calcineurin inhibitors, low-dose aspirin, testosterone, and lactate. In patients who have or are at risk for hyperuricemia or gout, an increased awareness of drugs that affect serum urate level may allow for prescribing that effectively treats the indicated problem while minimizing adverse effects on hyperuricemia and gout.

The Role of Urate in Cardiovascular Risk in Adolescents and Young Adults With Hypertension, Assessed by Pulse Wave Velocity

Background

Urate is increasingly recognized as a cardiovascular risk factor. It has been associated with hypertension, metabolic syndrome, obesity, chronic kidney disease and diabetes. Its prognostic role is less clear. The aim of our study was to evaluate the association between serum urate and pulse wave velocity, a measure of arterial stiffness in hypertensive adolescents and young adults.

Methods

269 adolescents and young adults with hypertension were included in the study. From all, anthropometric, blood pressure, pulse wave velocity and serum urate measurements were made. Variables were compared between sex, participants with or without obesity and with or without elevated urate.

Results

In multiple regression analysis for urate as dependent variable gender and diastolic pressure were found to be statistically significant. The difference between urate levels were found between boys and girls (p < 0.001), obese and non-obese (p < 0.001); however, pulse wave velocity did not differ between hyper- and eu-uricemic group (p = 0.162).

Conclusion

Associations between urate, gender, diastolic blood pressure and obesity were confirmed, however, no significant associations between pulse wave velocity and urate were detected.

Association between glucokinase regulator gene polymorphisms and serum uric acid levels in Taiwanese adolescents

The glucokinase regulator gene (GCKR) is located on chromosome 2p23. It plays a crucial role in maintaining plasma glucose homeostasis and metabolic traits. Recently, genome-wide association studies have revealed a positive association between hyperuricemia and GCKR variants in adults. This study investigated this genetic association in Taiwanese adolescents. Data were collected from our previous cross-sectional study (Taipei Children Heart Study). The frequencies of various genotypes (CC, CT, and TT) or alleles (C and T) of the GCKR intronic single-nucleotide polymorphism (SNP) rs780094 and the coding SNP rs1260326 (Pro446Leu, a common 1403C-T transition) were compared between a total of 968 Taiwanese adolescents (473 boys, 495 girls) with hyperuricemia or normal uric acid levels on the basis of gender differences. Logistic and linear regression analyses explored the role of GCKR in abnormal uric acid (UA) levels. Boys had higher UA levels than girls (6.68 ± 1.29 and 5.23 ± 0.95 mg/dl, respectively, p < 0.001). The analysis of both SNPs in girls revealed that the T allele was more likely to appear in patients with hyperuricemia than the C allele. After adjusting for confounders, the odds ratio (OR) for hyperuricemia incidence in the TT genotype was 1.75 (95% confidence interval [CI] 1.02–3.00), which was higher than that in the C allele carriers in rs1260326 in the girl population. Similarly, the TT genotypes had a higher risk of hyperuricemia, with an OR of 2.29 (95% CI 1.11–4.73) for rs1260326 and 2.28 (95% CI 1.09–4.75) for rs780094, than the CC genotype in girl adolescents. The T (Leu446) allele of GCKR rs1260326 polymorphism is associated with higher UA levels in Taiwanese adolescent girls.

Is There a Link Between Hormone Use and Diabetes Incidence in Transgender People? Data From the STRONG Cohort

BACKGROUND

Risk of type 2 diabetes mellitus (T2DM) in transgender and gender diverse (TGD) persons, especially those receiving gender-affirming hormone therapy (GAHT) is an area of clinical and research importance.

METHODS

We used data from an electronic health record-based cohort study of persons 18 years and older enrolled in 3 integrated health care systems. The cohort included 2869 transfeminine members matched to 28 300 cisgender women and 28 258 cisgender men on age, race/ethnicity, calendar year, and site, and 2133 transmasculine members similarly matched to 20 997 cisgender women and 20 964 cisgender men. Cohort ascertainment spanned 9 years from 2006 through 2014 and follow-up extended through 2016. Data on T2DM incidence and prevalence were analyzed using Cox proportional hazards and logistic regression models, respectively. All analyses controlled for body mass index.

RESULTS

Both prevalent and incident T2DM was more common in the transfeminine cohort relative to cisgender female referents with odds ratio and hazard ratio (95% CI) estimates of 1.3 (1.1-1.5) and 1.4 (1.1-1.8), respectively. No significant differences in prevalence or incidence of T2DM were observed across the remaining comparison groups, both overall and in TGD persons with evidence of GAHT receipt.

CONCLUSION

Although transfeminine people may be at higher risk for T2DM compared with cisgender females, the corresponding difference relative to cisgender males is not discernable. Moreover, there is little evidence that T2DM occurrence in either transfeminine or transmasculine persons is attributable to GAHT use.

Sex Disparities in the Association of Serum Uric Acid With Kidney Stone: A Cross-Sectional Study in China

Background and Aims

Urolithiasis is characterized by high rates of prevalence and recurrence. Hyperuricemia is related to various diseases. We hope to determine the association between serum uric acid (UA) level and kidney stone (KS).

Methods

In this population-based cross-sectional study, a total of 82,017 Chinese individuals who underwent a comprehensive examination in 2017 were included. The KS was diagnosed based on ultrasonography examination outcomes. Fully adjusted odds ratio (OR) for KS, and mean difference between the two groups were applied to determine the association of UA level with KS.

Results

Among the 82,017 participants included in this study (aged 18~99 years), 9,435 participants (11.5%) are diagnosed with KS. A proportion of 56.3% of individuals is male. The mean UA level of overall participants is 341.77 μmol/L. The participants with KS report higher UA level than the participants without KS [mean UA level 369.91 vs. 338.11 μmol/L; mean difference (MD), 31.96 (95% CI, 29.61~34.28) μmol/L]. In men, the OR for KS significantly increases from 330 μmol/L UA level. Every 50 μmol/L elevation of UA level increases the risk of KS formation by about 10.7% above the UA level of 330 μmol/L in men. The subgroup analysis for male is consistent with the overall result except for the participants presenting underweight [adjusted OR, 1.035 (0.875~1.217); MD, −5.57 (−16.45~11.37)], low cholesterol [adjusted OR, 1.088 (0.938~1.261); MD, 8.18 (−7.93~24.68)] or high estimated glomerular filtration rate (eGFR) [adjusted OR, 1.044 (0.983~1.108); MD, 5.61 (−1.84~13.36)]. However, no significant association is observed in women between UA and KS either in all female participants or in female subgroups.

Conclusion

Among Chinese adults, UA level is associated with KS in a dose-response manner in men but not in women. However, the association becomes considerably weak in male participants with malnutrition status.

Serum uric acid level is associated with an increase in systolic blood pressure over time in female subjects: Linear mixed-effects model analyses

Whether hyperuricemia is a true risk factor for elevated blood pressure (BP) is controversial, and the sex-specific effects of serum uric acid (SUA) on BP during a follow-up period remain unclear. We investigated whether the association of SUA level with systolic or diastolic BP during a 10-year period differs by sex in a Japanese general population of individuals who received annual health examinations (n = 28,990). After exclusion of subjects who had no BP or SUA data at baseline, a total of 22,994 subjects (male/female: 14,603/8391, age: 47 ± 11 years) were recruited. After adjustment for age; body mass index; BP; SUA level; use of drugs for hyperuricemia and hypertension; diagnosis of diabetes mellitus, dyslipidemia, and chronic kidney disease; family history of hypertension; habits of current smoking and alcohol consumption at baseline; the duration of the observation period; and the interaction between each covariate and the duration of the observation period indicated a significant association of SUA level with change in systolic or diastolic BP over time. There was a significant interaction between sex and SUA level for the change in systolic BP (P = 0.003) but not the change in diastolic BP (P = 0.081). The SUA level at baseline (per 1 mg/dL) was significantly associated with a change in systolic BP over time in females (estimate: 0.073 mmHg/year, P = 0.003) but not in males (estimate: 0.020 mmHg/year, P = 0.160). In conclusion, a high SUA level at baseline is significantly associated with an increase in systolic BP over time in female individuals but not in male individuals.

Mediating Effect of Body Mass Index and Dyslipidemia on the Relation of Uric Acid and Type 2 Diabetes: Results From China Health and Retirement Longitudinal Study

Objective

This study assessed temporal relationships of serum uric acid (SUA) with blood glucose and determine the mediating effects of body mass index (BMI) and dyslipidemia on the relation of SUA and risk of type 2 diabetes.

Methods

Participants aged ≥ 45 years were participated in 2011 and followed up until 2015. Cox proportional hazards regression with a robust variance estimator was performed to explore the association of SUA with the risk of diabetes, and crosslagged path analysis was introduced to examine the temporal relationships between SUA and blood glucose. A mediation analysis was finally used to identify the mediating effect of BMI and dyslipidemia on the relation of SUA and the future risk of diabetes.

Results

A total of 9,020 participants were included with an average age of 58.59 years at baseline in 2011, and 53.6% of them were women. Linear dose–response relationship was identified by restricted spline cubic analysis between baseline SUA and follow-up blood glucose (the non-linear trend for fasting plasma glucose (FPG): β2 = −0.71, p = 0.52; for HbA1c: β2 = 0.05, p = 0.07; for risk of diabetes: β2 = 0.12, p = 0.39). Additionally, compared with the lowest quartiles of SUA, the adjusted risk ratios of diabetes were 1.00 (95% CI: 0.82–1.23), 1.08 (95% CI: 0.89–1.31), and 1.37 (95% CI: 1.11–1.96) for quartile 2–4 (p-trend &lt; 0.01), respectively. Further additional adjustments for BMI or dyslipidemia, these ratios were not statistically significant. In addition, a unidirectional relationship from baseline SUA to follow-up FPG (ρ1 = 0.24, p = 0.03) was further confirmed using crosslagged path analysis. After stratifying by genders, the above results were only significant in the women subgroup, and we thus conducted a mediation analysis in women and found that the BMI and dyslipidemia partially mediated the effect of SUA on diabetes with a 23.05 and 18.82% mediating effect, respectively.

Conclusions

These findings provide strong evidence that hyperuricemia preceded diabetes, and the effect of baseline SUA on follow-up type 2 diabetes was more pronounced among middle-aged and elderly Chinese women, especially in postmenopausal women, and this effect is partly mediated by BMI and dyslipidemia at baseline.

The Mediation Effect of Body Composition on the Association Between Menopause and Hyperuricemia: Evidence From China National Health Survey

Reproductive factors have been demonstrated to be associated with hyperuricemia. Body composition is an essential determinant influencing serum uric acid (SUA), but it is largely unknown whether increased SUA was influenced by changed body composition during the menopausal transition. As a secondary analysis of China National Health Survey from 2012-to 2017, this study included 18,997 women aged 20 to 80. Menarche age and menopause information were collected by questionnaire interview. Body mass index (BMI), body fat percentage (BFP), fat mass index (FMI), and fat-free mass index (FFMI) were used as body composition indexes. Hyperuricemia was defined as SUA higher than 360μmol/L (approximately 6 mg/dl). Mediation analysis was performed to explore the direct and indirect effects of menopause on hyperuricemia. A 1:2 age-matched case-control data set (n=6202) was designed to control age-related confounders and was used in multivariable analyses. After adjustment of covariates, postmenopausal women had 14.08 (10.89-17.27) μmol/L higher SUA than their premenopausal counterparts. Overweight/obesity and higher levels of BFP, FMI, and FFMI were all found to be positively associated with hyperuricemia. The mediation analysis showed that the total effect of menopause on hyperuricemia was positive, but was substantially mediated by body composition indexes. Forty-five percent of the total effect can be attributed to the indirect effect mediated by BMI (OR for the natural indirect effect (NIE): 1.09, 95%CI: 1.04-1.13), and over 80% mediated by BFP (OR for NIE: 1.23, 95%CI: 1.16-1.29). However, FFMI did not present the mediated role in the association (OR for NIE: 0.99, 95%CI: 0.96-1.02). The findings revealed that body composition, especially the fat mass indexes, significantly mediated the association between menopause and hyperuricemia. The role of body composition as mediator constitutes clinical and public health significance that should be recognized and considered in healthcare for women experiencing their menopause transition.

Association between female reproductive factors and gout: a nationwide population-based cohort study of 1 million postmenopausal women

BACKGROUND

Previous studies have shown that the incidence and risk factors of gout differs according to sex. However, little research has been done on the association between reproductive factors and gout. We conducted an analysis of a large nationwide population-based cohort of postmenopausal women to determine whether there is an association between reproductive factors and the incidence of gout.

METHODS

A total of 1,076,378 postmenopausal women aged 40-69 years who participated in national health screenings in 2009 were included in the study. The outcome was the occurrence of incident gout, which was defined using the ICD-10 code of gout (M10) in the claim database. Cox proportional hazard models were used for the analyses and stratified analyses according to body mass index (BMI) and the presence/absence of chronic kidney disease (CKD) were performed.

RESULTS

The mean follow-up duration was 8.1 years, and incident cases of gout were 64,052 (incidence rate 7.31 per 1000 person-years). Later menarche, earlier menopause, and a shorter reproductive span were associated with a high risk of gout. No association between parity and gout incidence was observed. Use of oral contraceptives (OC) and hormone replacement therapy (HRT) were associated with an increased risk of gout. The association between reproductive factors and gout was not statistical significant in the high BMI group. The effects of OC and HRT usage on gout were not significant in the CKD group.

CONCLUSION

Shorter exposure to endogenous estrogen was associated with a high risk of gout. Conversely, exposure to exogenous estrogen such as OC and HRT was associated with an increased risk of gout.

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

Background

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

Methods

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

Results

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

Conclusions

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

The positive association between serum uric acid, impaired fasting glucose, impaired glucose tolerance, and diabetes mellitus in the ELSA-Brasil study

There is a conflict in the literature regarding the association between serum uric acid (SUA) levels and glycemic status. Therefore, we evaluated the association between SUA level and glycemic status - impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and diabetes mellitus - and insulin resistance, in a large Brazilian study. This is a cross-sectional, observational study with 13,207 participants aged 35-74 years, at baseline (2008-2010) of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). A multinomial regression analysis was performed to test the association between SUA and glycemic status (IFG, IGT, and newly diagnosed type 2 diabetes at the cohort baseline) after adjustments by age, sex, skin color, body mass index, physical activity, smoking, alcohol consumption, comorbidities, and medicines use. Logistic regression model was used to evaluate the association between SUA and insulin resistance by HOMA-IR. Stratified analyses by sex were performed. The mean age (standard deviation) was 51.4 (8.9) years, 55.2% of participants were women. There were 1,439 newly diagnosed diabetes. After all adjustments, higher SUA was associated with IFG, IGT, and diabetes, with odds ratio (OR) = 1.15 (95%CI: 1.06; 1.25), 1.23 (95%CI: 1.14; 1.33), and 1.37 (95%CI: 1.24; 1.51), respectively. There was association between SUA levels and insulin resistance with OR = 1.24 (95%CI: 1.13; 1.36). In analysis stratified by sex, higher SUA persisted independently associated with impaired glycemic status. Our results suggest that a higher SUA levels were significantly associated with glycemic status in a large Latin American population, mainly among women.

Effects of testosterone treatment on transgender males: A single-institution study

Objectives:

Data regarding gender-affirming hormone therapy in the Asian population are sparse. We aimed to evaluate the efficacy and safety of testosterone therapy in transgender men.

Methods:

A retrospective study chart review was conducted in a single university-based transgender clinic. Transgender men aged >18 years who newly started testosterone therapy during January 2015 to October 2019 were recruited. Physical changes, laboratory results, and adverse events, including cancer, thromboembolism, cardiovascular events, and death after masculinizing hormone therapy, were evaluated.

Results:

A total of 39 transgender men (mean age: 27.8 ± 6.0 years) were included. All individuals were treated with intramuscular testosterone injection with a mean follow-up of 25.2 ± 12.9 months. The most common maintenance regimen was testosterone enanthate 250 mg every 4 weeks. Masculinizing effects developed in all transgender men. There were no changes in body weight, and systolic and diastolic blood pressure. Hematocrit levels were 12% significantly increased from 39.9 ± 3.3% to 48.9 ± 2% (p < 0.001). Ten individuals (25.6%) had hematocrit >50%. Significant changes were found in decreased fasting plasma glucose, increased creatinine, and increased uric acid levels. A non-significantly increased alanine aminotransferase, increased low-density lipoprotein cholesterol, and decreased high-density lipoprotein cholesterol were observed. No thromboembolism, cancer, stroke, or coronary artery disease occurred.

Conclusions:

Gender-affirming hormone therapy is an effective and safe short-term treatment in Thai transgender men. Apart from the standard recommendation, uric acid, plasma glucose, and creatinine level evaluation before and during masculinizing hormone therapy are rational practices. An intramuscular testosterone enanthate 250 mg every 4 weeks is an alternative masculinizing regimen with decent efficacy and safety profile.

Establishment of sex difference in circulating uric acid is associated with higher testosterone and lower sex hormone-binding globulin in adolescent boys

Men have higher circulating levels of uric acid than women. This sex difference is suspected to be a result of suppressive effects of estradiol on uric acid. If so, estradiol would be inversely associated with circulating uric acid. This study aimed to test this hypothesis. This cross-sectional study included 9472 participants (weighted sample size of 184,342,210) aged 12-80 years from the 2013 to 2016 US National Health and Nutrition Examination Survey. Associations of sex hormones with uric acid were analyzed using weighted least squares regression, adjusting for demographic characteristics, lifestyle risk factors, and comorbidities. Neither free nor bioavailable estradiol was inversely associated with circulating uric acid in adolescent boys or girls, or adult men or women, or perimenopausal women after full adjustment. The sex difference in uric acid was established during adolescence as a result of a dramatic increase in uric acid in adolescent boys. During adolescence, the increase in estradiol in girls over time was accompanied by a relatively unchanged level of uric acid. All three fractions of estradiol (free, bioavailable, and total) were positively associated with uric acid in adolescent boys and girls after full adjustment. In adolescent boys, all three fractions of testosterone were positively associated with serum uric acid, and sex hormone-binding globulin was inversely associated with uric acid after full adjustment. These results suggest that estradiol is not inversely associated with circulating uric acid in adolescents and the establishment of sex difference in circulating uric acid during adolescence is associated with higher testosterone and lower sex hormone-binding globulin in adolescent boys.

Sex-Specific Association of Uric Acid and Kidney Function Decline in Taiwan

An elevated serum urate concentration is associated with kidney damage. Men’s uric acid levels are usually higher than women’s. However, postmenopausal women have a higher risk of gout than men, and comorbidities are also higher than in men. This study examined the sex differences in the relationship between hyperuricemia and renal progression in early chronic kidney disease (CKD) and non-CKD, and further examined the incidence of CKD in non-CKD populations among patients over 50 years of age. We analyzed 1856 women and 1852 men participating in the epidemiology and risk factors surveillance of the CKD database. Women showed a significantly higher risk of renal progression and CKD than men within the hyperuricemia group. After adjusting covariates, women, but not men resulted in an hazard ratio (HR) for developing renal progression (HR = 1.12; 95% CI 1.01–1.24 in women and HR = 1.03; 95% CI 0.93–1.13 in men) and CKD (HR = 1.11; 95% CI 1.01–1.22 in women and HR = 0.95; 95% CI 0.85–1.05 in men) for each 1 mg/dL increase in serum urate levels. The association between serum urate levels and renal progression was stronger in women. Given the prevalence and impact of kidney disease, factors that impede optimal renal function management in women and men must be identified to provide tailored treatment recommendations.

Alcohol consumption and serum uric acid are synergistically associated with renal dysfunction among community-dwelling persons

Background

Serum uric acid (SUA) is a key risk factor contributing to renal failure, a serious public health problem. However, few studies have examined whether the interactive relationship between alcohol consumption and SUA is independently associated with the estimated glomerular filtration rate (eGFR).

Methods

Our sample comprised 742 men aged 69 ± 11 years (mean ± standard deviation) and 977 women aged 69 ± 10 years from a rural area. We cross‐sectionally examined the relationships between the confounding factors of alcohol consumption and SUA with renal function denoted by eGFR estimated using CKD‐EPI (Chronic Kidney Disease Epidemiology Collaboration) equations modified by a Japanese coefficient.

Results

In both genders, eGFR increased with a rise in alcohol consumption. This tendency was more pronounced in participants with hyperuricemia, where SUA was greater than 7.0 mg/dL in men and greater than 6.0 mg/dl in women (men: F = 41.98, p < 0.001; women: F = 41.98, p < 0.001). A multiple linear regression analysis showed that alcohol consumption (men: β = 0.112, p < 0.001; women: β = 0.060, p = 0.011) and SUA (men: β = −0.282, p < 0.001; women: β = 0.317, p < 0.001) were significantly and independently related to eGFR. Further, the interactive relationship between alcohol consumption and SUA (men: F = 6.388, p < 0.001; women: F = 5.368, p < 0.001) was a significant and independent indicator of eGFR.

Conclusions

These results suggested that alcohol consumption and SUA were synergistically associated with renal dysfunction among community‐dwelling persons.

Serum uric acid is positively associated with the prevalence of nonalcoholic fatty liver in non-obese type 2 diabetes patients in a Chinese population

AIMS

To investigate whether SUA is independently associated with NAFLD in non-obese type 2 diabetic patients in a Chinese population.

METHODS

A cross-sectional study was carried out among 400 non-obese type 2 diabetic inpatients. Patients were stratified according to SUA levels and presence/absence of NAFLD. The clinical and laboratory features were collected retrospectively. Multivariate logistic regression analysis was conducted to estimate odds ratios of SUA for NAFLD.

RESULTS

The levels of SUA were significantly higher in patients with NAFLD than those without NAFLD. SUA was positively associated with the risk factors of NAFLD such as BMI, serum insulin and lipids. The odds of NAFLD were increasingly higher from the second to the fourth quartile of SUA as compared to the lowest quartile. After adjustment for age, gender, BMI and other metabolic components, the odds of NAFLD remained significantly increased for quartile 4.

CONCLUSIONS

SUA levels are strongly and independently associated with the prevalence of NAFLD. SUA may be used as a useful predictor to stratify the higher risks for NAFLD of non-obese type 2 diabetes patients.

Temporal trends in hyperuricaemia among adults in Wuhan city, China, from 2010 to 2019: a cross-sectional study

OBJECTIVES

Hyperuricaemia is a risk factor for gout attacks, kidney damage and cardiovascular events. Evidence on the trends in hyperuricaemia burden in Wuhan city, China, was limited. The present study aimed to estimate the prevalence of and a decade trend in hyperuricaemia in Wuhan city.

DESIGN

Cross-sectional study.

SETTING

Health Management Center of Tongji Hospital.

PARTICIPANTS

A total of 732 527 adult participants from the general population who took a physical examination in the Health Management Center between 2010 and 2019.

MAIN OUTCOME MEASURES

Prevalence of and trends in hyperuricaemia.

RESULTS

The overall prevalence of hyperuricaemia was 25.8% (36.6% in men and 10.8% in women) in 2019. The hyperuricaemia prevalence and serum uric acid (SUA) levels were significantly higher in young men, old women and participants with obesity, hypertension, diabetes or dyslipidaemia (p<0.05). SUA levels among men and women gradually increased from 358.0 (313.0-407.0) umol/L and 250.0 (217.0-288.0) umol/L in 2010 to 388.0 (338.0-445.2) umol/L and 270.0 (233.0-314.0) umol/L in 2019, respectively, p<0.05. From 2010 through 2019, hyperuricaemia prevalence significantly increased in each age category and it increased most sharply among participants aged 20-39 years. The multivariate-adjusted prevalence among men was 26.1% (25.4% to 26.7%) in 2010, 30.9% (30.4% to 31.4%) in 2015 and 34.4% (34.1% to 34.8%) in 2019, while among women it was 5.8% (5.4% to 6.2%) in 2010, 7.2% (6.9% to 7.5%) in 2015 and 10.1% (9.9% to 10.3%) in 2019.

CONCLUSIONS

Hyperuricaemia was highly prevalent among adults in Wuhan city. More attention should be paid to the increasing burden of hyperuricaemia, especially for those at higher risks.

Relationship between seaweeds consumption and hyperuricaemia in general adults: a Population-based study from the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study

Seaweeds have numerous biologically active ingredients, such as polysaccharides, polyphenols and carotenoids, that are beneficial to human health. Although these benefits might be related to the synthesis, secretion or reabsorption of uric acid, no studies have explored the relationship between seaweeds consumption and hyperuricaemia (HUA) in the general population. The aim of this study was to investigate whether seaweeds consumption is related to HUA in a large-scale adult population. A cross-sectional study was conducted with 32 365 adults (17 328 men and 15 037 women) in Tianjin, People's Republic of China. Frequency of seaweeds consumption was assessed by a validated self-administered FFQ. HUA was defined as serum uric acid levels >420 μmol/L in men and >350 μmol/L in women. The association between seaweeds consumption and HUA was assessed by multiple logistic regression analysis. Restricted cubic spline functions were used for non-linearity tests. The prevalence of HUA in men and women was 21·17 % and 5·93 %, respectively. After adjustments for potential confounding factors, the OR (95 % CI) for HUA across seaweed consumption (g/1000 kcal per d) were 1·00 (reference) for level 1, 0·91 (95 % CI 0·81, 1·02) for level 2; 0·90 (95 % CI 0·81, 1·01) for level 3; 0·86 (95 % CI 0·78, 0·97) for level 4 in men and 0·90 (95 % CI 0·73, 1·10) for level 2; 0·82 (95 % CI 0·67, 1·00) for level 3; 0·84 (95 % CI 0·68, 1·03) for level 4 in women, respectively. A negative correlation between seaweeds consumption and HUA in males but not in females was observed. Further studies are needed to explore the causal relationship.

Metabolic effects of cross-sex hormone therapy in transgender individuals in Taiwan

BACKGROUND

Transgender individuals often require gender-affirming interventions, such as endogenous sex hormone inhibition or gender-affirming hormone therapy (HT), while there is discordance between their body and gender identity. However, a recent study found that the incidence of cardiovascular events is higher in transgender patients receiving cross-sex HT. The aim of this study was to investigate the metabolic effects of an altered sex hormone profile.

METHODS

This retrospective study, conducted in a referral center in Northern Taiwan, analyzed metabolic changes over time in 65 trans masculine and 45 trans feminine persons. The transgender individuals were examined at 4 time points: before the gender affirming HT, as well as 3, 6, and 12 months following treatment.

RESULTS

Compared with baseline measurements, the trans masculine patients showed significant increases in body mass index (BMI) (22.6 ± 0.3 vs 23.3 ± 0.4 kg/m2; p < 0.001; t = 3M), low-density lipoprotein cholesterol (124.3 ± 3.7 vs 131.3 ± 3.9 mg/dL; p = 0.03; t = 12M), creatinine (0.75 ± 0.01 vs 0.83 ± 0.14 mg/dL; p < 0.001; t = 12M), and hemoglobin (13.5 ± 0.7 vs 15.2 ± 0.2 g/dL; p < 0.001; t = 12M), as well as decreased high-density lipoprotein cholesterol (57 ± 2.1 vs 51 ± 2.0 mg/dL; p < 0.001; t = 12M). The trans feminine patients had reduced low-density lipoprotein cholesterol (104.2 ± 3.2 vs 100.8 ± 3.5 mg/dL; p = 0.05; t = 3M), hemoglobin (14.0 ± 0.1 vs 13.5 ± 0.1 g/dL; p = 0.008; t = 12M), and creatinine (0.82 ± 0.01 vs 0.79 ± 0.14 mg/dL; p < 0.001; t = 3M) compared with baseline data. In addition, most of these metabolic effects persisted during the follow-up period.

CONCLUSION

This observational, retrospective study revealed that gender-affirming HT increased the relative cardiovascular risk in trans masculine individuals.

Gender-specific association between non-alcoholic fatty liver disease and type 2 diabetes mellitus among a middle-aged and elderly Chinese population: An observational study

ABSTRACT

Limited data are available regarding the association of non-alcoholic fatty liver disease (NAFLD) with the risk of type 2 diabetes mellitus (T2DM) in China. Therefore, the purpose of this study is to evaluate the gender-specific association between NAFLD and T2DM risk in a middle-aged and elderly Chinese population.This cross-sectional study was carried out in a group of 1492 Chinese adults (60.30% males) aged between 45 and 69 years old, in Hangzhou city, Zhejiang province who were attending their annual health check-up from June 2015 to December 2016 in the Medical Center for Physical Examination, Zhejiang Hospital. Face-to-face interviews were conducted using a written questionnaire. NAFLD was divided into none, mild, moderate/severe based on ultrasound examination. Logistic regression analyses were employed to determine the relationship between NAFLD and the risk of T2DM, with adjustment of potential confounding variables.Of the 1492 participants, 163 (10.92%) were diagnosed with T2DM. Educational level, smoking, body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose (FG), triglycerides (TG), alanine aminotransferase (ALT), asparagine aminotransferase (AST)and the prevalence of T2DM were significantly higher in males than in females (P < .05). Besides, females had significantly higher levels of high density lipoprotein-cholesterol (HDL-C) (1.51 ± 0.37 vs 1.29 ± 0.42, P < .001) than males. Pearson bivariate correlation analysis indicated that FG was positively associated with weight, BMI, WC, WHR, SBP, DBP, TG, TC, ALT and AST in both males and females (P < .05). Besides, FG was inversely associated with HDL-C in females (P < .001). After adjusting for confounding variables, NAFLD was positively associated with the risk of T2DM, and the effect of NAFLD on T2DM was stronger in males (OR = 2.442, 95%CI: 1.003-3.757) than in females (OR = 1.814, 95%CI: 1.011-3.257).Our data showed that NAFLD was significantly associated with the risk of T2DM in middle-aged and elderly males than in females. Further prospective cohort studies are needed to determine the causal effect of NAFLD on T2DM.

Exploration of the association between serum uric acid and testosterone in adult males: NHANES 2011-2016

Background

Previous studies have suggested that the possible relationship between serum uric acid (SUA) and testosterone. However, the results of previous studies are controversial and there is limited evidence examining the relationship between SUA and testosterone in a general US population of men. The objective of this study is to explore the correlation of SUA and testosterone among adult males from the US.

Methods

Data from the National Health and Nutrition Examination Survey 2011–2016 were used, including a total of 7,796 male participants aged 18 years or older and excluding those lacking serum testosterone and uric acid data. Clinical characteristics of the participants among different SUA groups and testosterone groups are compared. Univariate and multivariate linear regression analyses were applied to evaluate the association between SUA and testosterone.

Results

We found an inverse association between SUA and testosterone after fully adjusted the potential confounding factors in general US adult males. In the multivariate linear regression analysis, we found that increasing age (estimate testosterone percent difference: −0.20% per year, P<0.01), uric acid (estimate testosterone percent difference: −4.40% per md/dL, P<0.01) and BMI (estimate testosterone percent difference: −2.86% per kg/m2, P<0.01) were associated with declining serum testosterone. This association remained significant in sensitivity analysis, while in the stratified analysis, above association was not significant in men with diabetes or aged 65 and over.

Conclusions

SUA levels might be negatively associated with serum testosterone in adult males.

Insulin resistance in transgender individuals correlates with android fat mass

BACKGROUND

Transgender individuals receiving gender-affirming hormone therapy (GAHT) are at increased risk of adverse cardiovascular outcomes. This may be related to effects on body composition and insulin resistance.

AIMS

To examine relationships between body fat distribution and insulin resistance in transgender individuals on established GAHT.

METHODS

Comparisons of body composition (dual energy X-ray absorptiometry) and insulin resistance [Homeostasis Model of Insulin Resistance (HOMA2-IR)] were made between transgender individuals (43 trans men and 41 trans women) on established GAHT (>12 months) and age-matched cisgender controls (30 males and 48 females). Multiple linear regressions were used to examine the relationship between HOMA2-IR and fat mass with gender, adjusting for age and total duration of GAHT and Pearson correlation coefficients are reported.

RESULTS

Compared with control cisgender women, trans men had mean difference of +7.8 kg (4.0, 11.5), p < 0.001 in lean mass and higher android:gynoid fat ratio [0.2 (0.1, 0.3), p < 0.001], but no difference in overall fat mass or insulin resistance. Compared with control cisgender men, trans women had median difference in lean mass of -6.9 kg (-10.6, -3.1), p < 0.001, fat mass of +9.8 kg (3.9, 14.5), p = 0.001, lower android:gynoid fat ratio -0.1 (-0.2,-0.0), p < 0.05), and higher insulin resistance 1.6 (1.3-1.9), p < 0.001). Higher HOMA2-IR correlated with higher android (r ² = 0.712, p < 0.001) and gynoid (r ² = 0.572, p < 0.001) fat mass in both trans men and trans women.

CONCLUSION

Android fat more strongly correlates with insulin resistance than gynoid fat in transgender individuals. Higher fat mass and insulin resistance in trans women may predispose to increased cardiovascular risk. Despite adverse fat distribution, insulin resistance was not higher in trans men.

Associations of Blood Heavy Metals with Uric Acid in the Korean General Population: Analysis of Data from the 2016-2017 Korean National Health and Nutrition Examination Survey

We hypothesized that blood heavy metal levels such as lead, cadmium, and mercury were associated with uric acid level and hyperuricemia, and that this association remains significant after adjustment for other metals. We tested this hypothesis using the Korean National Health and Nutrition Examination Survey data. Beta coefficients and 95% confidence intervals (95% CIs) were calculated using multiple linear regression, and odds ratios (ORs) and 95% CIs were calculated using logistic regression in the cross-sectional study design. Relative to women, men had a higher geometric mean (GM) of lead (1.95 vs. 1.50 μg/dL) and mercury (3.94 vs. 2.77 μg/L), a lower GM of cadmium (0.80 vs. 1.04 μg/L), and a higher arithmetic mean (AM) of uric acid (5.84 vs. 4.40 mg/dL). Women had significant positive associations of log uric acid level with doubling of lead and mercury, and negative association with cadmium. Logistic regression analysis indicated the inverse association of serum hyperuricemia with doubling of blood metals was only significant for cadmium in women (OR = 0.641, 95% CI = 0.463 to 0.886) and the associations of serum hyperuricemia in the highest versus lowest quartiles of heavy metals were only significant for cadmium in women (OR = 0.495, 95% CI = 0.246 to 0.998). For both genders, age and estimated glomerular filtration rate (e-GFR) had negative associations with uric acid, but hypertension and triglycerides had positive associations with uric acid. In conclusion, blood lead and mercury levels were positively associated with uric acid level, but blood cadmium level was inversely associated with uric acid level and hyperuricemia in women.

Age and Gender-Specific Reference Intervals for Uric Acid Level in Children Aged 5-14 Years in Southeast Zhejiang Province of China: Hyperuricemia in Children May Need Redefinition

Context: Hyperuricemia is defined when the plasma uric acid concentration is above 416 μmol/L (7 mg/dl) in male adults, or 357 μmol/L (6 mg/dl) in female adults. However, there are no explicit criteria yet for children. Objective: It is necessary to set up reference intervals for the uric acid level in different age groups among children. Materials and Methods: A total of 5,439 individuals (3,258 males, 2,181 females) were included in the final statistical analysis. Reference values of all age groups were determined by statistical descriptions. Multiple linear regression analysis was applied to determine the relationship between uric acid level, BMI, and age. Results: The level of uric acid increased with age. Gender differences in uric acid level occurred after the onset of puberty. Additionally, linear regression revealed a positive correlation between the uric acid level and BMI. Discussion and Conclusion: The reference range of the uric acid level in children is inconsistent with the previous viewpoint. Body mass index plays an important role in uric acid metabolism.

27-Hydroxycholesterol regulates human SLC22A12 gene expression through estrogen receptor action

The excretion and reabsorption of uric acid both to and from urine are tightly regulated by uric acid transporters. Metabolic syndrome conditions, such as obesity, hypercholesterolemia, and insulin resistance, are believed to regulate the expression of uric acid transporters and decrease the excretion of uric acid. However, the mechanisms driving cholesterol impacts on uric acid transporters have been unknown. Here, we show that cholesterol metabolite 27‐hydroxycholesterol (27HC) upregulates the uric acid reabsorption transporter URAT1 encoded by SLC22A12 via estrogen receptors (ER). Transcriptional motif analysis showed that the SLC22A12 gene promoter has more estrogen response elements (EREs) than other uric acid reabsorption transporters such as SLC22A11 and SLC22A13, and 27HC‐activated SLC22A12 gene promoter via ER through EREs. Furthermore, 27HC increased SLC22A12 gene expression in human kidney organoids. Our results suggest that in hypercholesterolemic conditions, elevated levels of 27HC derived from cholesterol induce URAT1/SLC22A12 expression to increase uric acid reabsorption, and thereby, could increase serum uric acid levels.

Increased Cerebrospinal Fluid Uric Acid Levels in Guillain-Barré Syndrome

Uric acid (UA) is a natural scavenger for peroxynitrite and can reflect antioxidant activity and oxidative stress in several neurological disorders. Changes in serum and cerebrospinal fluid (CSF) levels of UA have been reported in patients with multiple sclerosis and neuromyelitis optica spectrum disorders. The levels of UA in CSF are relatively poorly understood in patients with Guillain–Barré syndrome (GBS). It remains unclear whether UA can play an antioxidant role and reflect oxidative stress in GBS. The purpose of this study is to investigate CSF and serum UA levels in patients with GBS and their relationship with clinical characteristics. The CSF and serum UA levels were detected in 43 patients with GBS, including 14 acute inflammatory demyelinating polyneuropathy (AIDP), 6 acute motor axonal neuropathy (AMAN), 13 with acute motor and sensory axonal neuropathy (AMSAN), 7 Miller Fisher syndrome (MFS), and 3 unclassified, and 25 patients with non-inflammatory neurological disorders (NIND) as controls. Moreover, serum UA levels were also detected in 30 healthy controls. The levels of UA were measured using uricase-based methods with an automatic biochemical analyzer. CSF UA levels were significantly increased in patients with GBS (p = 0.011), particularly in patients with AIDP (p = 0.004) when compared with NIND. Among patients with GBS, CSF UA levels were higher in those with demyelination (p = 0.022), although the difference was not significant after multiple testing correction. CSF UA levels in GBS were positively correlated with serum UA levels (r = 0.455, p = 0.022) and CSF lactate (r = 0.499, p = 0.011). However, no significant correlations were found between CSF UA levels and GBS disability scores. There were no significant differences in serum UA levels among GBS, NIND, and healthy controls. These results suggest that CSF UA may be related to the pathogenesis of demyelination in patients with GBS and may be partially determined by serum UA and the impaired blood–nerve barrier.

The haplotype of SLC2A9_rs3733591, PKD2_rs2725220 and ABCG2_rs2231142 increases the hyperuricaemia risk and alcohol, chicken and processed meat intakes and smoking interact with its risk

We determined that a genetic haplotype increased the risk of hyperuricaemia and it interacted with lifestyle factors, including nutrients in 28,445 middle-aged Koreans. ABCG2_rs2231142, PKD2_rs2725220 and SLC2A9_rs3733591 were selected from GWAS based on hyperuricaemia (≥7 mg/dL; p = 6.88E-42, 1.56E-26 and 1.01E-20, respectively). Hyperuricaemia and gout were elevated by 3.93- and 3.23-fold, respectively, by the minor alleles as compared with the major alleles of the haplotype of the selected 3 SNPs after adjusting for covariates. The haplotype significantly interacted with alcohol, chicken and processed meat intakes, and smoking status in the hyperuricaemia risk (p = 0.002-0.007). Minor alleles of the haplotype had an association with hyperuricaemia as compared with major alleles particularly in high intakes of alcohol (2g/day), chicken (6.3g/day), and processed meat (3g/day) and smokers. In conclusion, people carrying minor alleles of the haplotype of SLC2A9_rs3733591, PKD2_rs2725220 and ABCG2_rs2231142 should avoid diets high in chicken and processed meat, alcohol drinking, and cigarette smoking to protect against hyperuricaemia risk.