Body mass index modulates the relationship of sugar-sweetened beverage intake with serum urate concentrations and gout

Associations of low-carbohydrate diets patterns with the risk of hyperuricemia: a national representative cross-sectional study in Korea

BACKGROUND

The association between low-carbohydrate diets and hyperuricemia risk, a significant risk factor for gout and cardiometabolic morbidities, remains inconclusive, partly due to differing effects of replacing carbohydrates with animal- or plant-based macronutrients. This study examined associations between low-carbohydrate diet patterns and hyperuricemia risk in 39,880 adults in the Korea National Health and Nutritional Examination Study 2016-2022.

METHODS

Diet was assessed via a 24-hour dietary recall. The overall, animal-rich, and plant-rich low-carbohydrate diet score (LCDS) was calculated based on percent energy derived from protein and fat in animal and plant food sources. Hyperuricemia was defined as serum uric acid levels > 7.0 mg/dL for men and > 6.0 mg/dL for women. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression models to estimate the risk of hyperuricemia across quintiles of LCDS.

RESULTS

A significantly greater risk of hyperuricemia was observed among individuals with higher overall LCDS (OR for quintile 5 vs. quintile 1 [Q5vs.Q1]: 1.41, 95%CI:1.22-1.63, P-trend: <0.001) and animal-rich LCDS (ORQ5vs.Q1: 1.28, 95%CI:1.12-1.47, P-trend: <0.001), but not with plant-rich LCDS (ORQ5vs.Q1: 1.00, 95%CI: 0.87-1.16). These positive associations for overall LCDS and animal-rich LCDS were evident in overweight individuals (ORQ5vsQ1: 1.53, 95%CI: 1.29-1.82 for overall LCDS; and 1.39, 95%CI: 1.19-1.63 for animal-rich LCDS; all P-trends < 0.001), but not in non-overweight individuals (all P-interactions: <0.001).

CONCLUSIONS

In our study, animal-based low-carbohydrate diets were associated with a greater risk of hyperuricemia, while no association was observed for plant-based low-carbohydrate diets. Larger cohort studies are warranted to replicate these findings.

The mediating roles of anthropo-metabolic biomarkers on the association between beverage consumption and breast cancer risk

BACKGROUND

Breast cancer (BC) is the most common malignancy in women, yet the role of beverage consumption in BC risk remains unclear. Additionally, the contribution of anthropo-metabolic biomarkers as mediators is unknown, limiting the development of effective prevention strategies.

METHODS

This study included 13,567 participants from the Guangzhou Biobank Cohort Study (GBCS), where beverage consumption was assessed at baseline using a food frequency questionnaire. BC cases were identified through cancer registry linkage over a mean follow-up of 14.8 years. Mendelian randomization (MR) analyses were performed to evaluate the causal effects of beverage consumption on BC risk, with a two-step MR approach used to estimate mediation effects.

RESULTS

During follow-up, 243 BC cases were identified. Weekly consumption of ≥ 1 portion of sugar sweetened beverages (SSB), versus < 1 portion, was significantly associated with a higher risk of BC (hazard ratio [HR] 1.58, 95% confidence interval [CI] 1.12-2.23). This association was partly mediated by body mass index (proportion mediated [PM] 4.2%, 95% CI 0.9-17.1%) and uric acid (PM 18.8%, 95% CI 1.5-77.5%). Weekly consumption of > 6 portions of dairy-based milk was associated with a non-significantly higher BC risk (HR 1.41, 95% CI 0.99-2.03), while 3-6 portions of soy milk were associated with a lower BC risk (HR 0.31, 95% CI 0.10-0.98). No significant associations were found for pure fruit juice, coffee, tea, or alcoholic drinks. MR analyses supported the detrimental effect of SSB on BC risk, with high-density lipoprotein cholesterol, polyunsaturated fatty acids to total fatty acids (TFAs) ratio, and omega-6 fatty acids to TFAs ratio mediating 2.44%, 2.73%, and 3.53% of the association, respectively.

CONCLUSION

This study suggested that SSB consumption was a risk factor for BC and identified key anthropo-metabolic biomarkers mediating this relationship. Reducing SSB consumption and addressing associated metabolic pathways may offer effective strategies for BC prevention.

Association of body weight and serum uric acid with Alzheimer's disease biomarkers and cognitive impairment

BackgroundGiven the limited effective treatments for Alzheimer's disease (AD), obesity and serum uric acid (SUA) levels which are considered modifiable risk factors for dementia are of interest. However, research indicates conflicting results.ObjectiveWe aimed to further investigate the association of body weight (BW) and SUA with AD biomarkers and cognitive impairment.MethodsClinical data were collected from 139 adults (mean age 66.9 years) with chronic cognitive impairment. Cerebrospinal fluid (CSF) biomarkers and PET imaging were used to assess amyloid-β (A) and Tau (T) tangles load, classifying participants into AT profiles based on the results. The association of BW and SUA with AT profiles was evaluated using multivariable logistic regression, and their relationship with cognitive function (Mini-Mental State Examination (MMSE) scores) were analyzed using multivariable linear regression.ResultsLower BW levels significantly influenced the presence of Aβ positive state (A+) (p = 0.007), while SUA levels did not (p = 0.263). Higher dementia proportion (p = 0.021), lighter BW (p = 0.019), and lower mean arterial pressure (MAP) levels (p = 0.025) were associated with AD pathological progress (A-T-→A+T-→A+T+), but SUA was not observed statistically significant. Among all participants regardless of Aβ state, high education levels (p < 0.001), high BW (p = 0.010), and high SUA (p=0.036) were associated with high MMSE scores, and high serum creatinine (p = 0.003) was associated with low MMSE scores.ConclusionsLower BW may accelerate AD pathology and cause cognitive impairment, while SUA is not linked to AD pathological progression but protects cognitive function.

Associations of the ALDH2 rs671 polymorphism and alcohol intake with early-onset gout in a Chinese male cohort

OBJECTIVE

Gout in young people is increasingly common across the world, including in China. This study aimed to identify clinical and genetic associations with early-onset gout in Chinese men.

METHODS

One thousand two hundred and one Chinese men with gout were included. Early-onset gout was defined as the first presentation of gout at <30years. Twenty single nucleotide polymorphisms (SNPs) identified as gout-risk loci or associated with serum urate (SU) levels in East Asian populations were genotyped. Logistic regression was used to evaluate the association of SNPs and clinical factors with early-onset gout.

RESULTS

Four hundred and thirty-three (36.1%) participants were identified as having early-onset gout. These patients had higher SU levels and were more likely to experience gout flares than those with later-onset gout. The ALDH2 rs671 GG genotype was associated with a lower risk of early-onset gout. Compared to those with GG genotype who never drank alcohol before gout onset, individuals with AA or AG genotypes who drank alcohol before gout onset had a higher likelihood of early-onset gout. Additionally, alcohol intake significantly increased the likelihood of gout flares in early-onset gout patients. Moreover, body mass index, sugar-sweetened beverage intake, family history of gout and renal urate underexcretion were associated with early-onset gout.

CONCLUSIONS

The ALDH2 rs671 GG genotype was significantly associated with a lower risk of early-onset gout, while individuals with the AA or AG genotype who consumed alcohol were more susceptible. These findings indicate that alcohol intake is a potentially modifiable risk factor for early-onset gout in genetically susceptible individuals.

Pacific Islands Families Study: Serum Uric Acid in Pacific Youth and the Associations with Free-Sugar Intake and Appendicular Skeletal Muscle Mass

BACKGROUND

Fructose (50% of sucrose/sugar) is one component of free-sugars and is metabolized to uric acid, which is a known risk factor for gout and metabolic syndrome. Pacific peoples in New Zealand experience a higher prevalence of gout, type 2 diabetes, and overweight/obesity than other ethnic groups. Interestingly, despite having a similar body mass index (BMI), they tend to have a higher proportion of appendicular skeletal muscle mass (ASMM) and less fat than other ethnic groups. Given this context, this study aimed to evaluate the associations between serum uric acid (SUA), free-sugar intake, and ASMM.

METHODS

In a nested sub-study from the Pacific Islands Families birth-cohort study, 101 boys and 99 girls (all aged 14 and 15 years) self-reported how often they had consumed foods containing sugar in the past month. Anthropometry, body fatness, and ASMM by dual-energy X-ray absorptiometry and metabolic risk factors, including SUA were measured.

RESULTS

Overall, 43% of girls and 57% of boys consumed 'sugary drinks' twice or more a day. When analyzed by group, ASMM was positively related to SUA for both boys and girls (r = 0.593, p < 0.0001). The effect of the intake of 'sugary drinks' on SUA (r = 0.176, p = 0.013) was reduced when ASMM was considered in the relationships.

CONCLUSIONS

This study shows high SUA levels in Pacific adolescents, with a positive association between ASMM and SUA in both genders. Sugary drink intake was positively associated with SUA in both boys and girls. High ASMM in Pacific people and an increased risk for raised SUA make it important to work with Pacific communities to reduce added sugar intake and adopt integrated, family-based, culturally centered, and life-course approaches to prevent chronic diseases, including gout.

The development of a novel high-throughput membrane potential assay and a solid-supported membrane (SSM)-based electrophysiological assay to study the pharmacological inhibition of GLUT9/SLC2A9 isoforms in a drug discovery program

GLUT9/SLC2A9 is a urate transporter and takes a fundamental role in the maintenance of normal serum urate levels. GLUT9 is the sole transporter of reabsorbed urate from renal epithelial cells to blood, thus making it an ideal pharmacological target for the development of urate-lowering drugs. None of the three currently available assays for studying GLUT9 pharmacological inhibition can support a high throughput drug discovery screening campaign. In this manuscript we present two novel assay technologies which can be used in a drug discovery screening cascade for GLUT9: a GLUT9 membrane potential assay for primary screening; and a solid-supported membrane (SSM)-based supported electrophysiological assay for secondary screening.

Associations of serum uric acid variability with neuroimaging metrics and cognitive decline: a population-based cohort study

BACKGROUND

The relationship between variation in serum uric acid (SUA) levels and brain health is largely unknown. This study aimed to examine the associations of long-term variability in SUA levels with neuroimaging metrics and cognitive function.

METHODS

This study recruited 1111 participants aged 25-83 years from a multicenter, community-based cohort study. The SUA concentrations were measured every two years from 2006 to 2018. We measured the intraindividual SUA variability, including the direction and magnitude of change by calculating the slope value. The associations of SUA variability with neuroimaging markers (brain macrostructural volume, microstructural integrity, white matter hyperintensity, and the presence of cerebral small vessel disease) and cognitive function were examined using generalized linear models. Mediation analyses were performed to assess whether neuroimaging markers mediate the relationship between SUA variation and cognitive function.

RESULTS

Compared with the stable group, subjects with increased or decreased SUA levels were all featured by smaller brain white matter volume (beta =  - 0.25, 95% confidence interval [CI] - 0.39 to - 0.11 and beta =  - 0.15, 95% CI - 0.29 to - 0.02). Participants with progressively increased SUA exhibited widespread disrupted microstructural integrity, featured by lower global fractional anisotropy (beta =  - 0.24, 95% CI - 0.38 to - 0.10), higher mean diffusivity (beta = 0.16, 95% CI 0.04 to 0.28) and radial diffusivity (beta = 0.19, 95% CI 0.06 to 0.31). Elevated SUA was also associated with cognitive decline (beta =  - 0.18, 95% CI - 0.32 to - 0.04). White matter atrophy and impaired brain microstructural integrity mediated the impact of SUA increase on cognitive decline.

CONCLUSIONS

It is the magnitude of SUA variation rather than the direction that plays a critical negative role in brain health, especially for participants with hyperuricemia. Smaller brain white matter volume and impaired microstructural integrity mediate the relationship between increased SUA level and cognitive function decline. Long-term stability of SUA level is recommended for maintaining brain health and preventing cognitive decline.

Lifestyle factors predict gout outcomes: Results from the NOR-Gout longitudinal 2-year treat-to-target study

OBJECTIVE

Gout is associated with lifestyle, body mass index (BMI) and comorbidities, including dyslipidaemia. We studied how in actively treated patients, anthropometric measures and lipid levels changed over 2 years and whether they predicted gout outcomes.

METHODS

Patients with a recent gout flare and elevated serum urate (sUA) received gout education and treat-to-target urate-lowering therapy over 1 year. Anthropometric measures with BMI, waist circumference (WC) and waist-height ratio (WHR) as well as lipid levels were measured yearly over 2 years. We examined whether baseline anthropometric measures and lipid levels were related to flares and to achieving the sUA target.

RESULTS

At baseline, patients (n=211) were with mean age of 56.4 years and 95% were male. Over 2 years, anthropometric measures were largely unchanged while cholesterol and low-density lipoprotein cholesterol (LDL-C) were reduced at year 1. Anthropometric measures were associated with presence of tophi. Higher baseline WC (OR: 0.96 per cm, 95% CI: 0.93 to 0.99) decreased and high level of high-density lipoprotein cholesterol (OR: 5.1 per mmol/L, 95% CI: 1.2 to 22.1) increased the chance of sUA target achievement at year 2. High LDL-C (OR: 1.8 per mmol/L, 95% CI: 1.2 to 2.6) predicted the chance of having a gout flare during year 2.

CONCLUSION

In actively treated patients with gout, anthropometric measures were largely unchanged over 2 years and lipid levels were reduced. High WC and lipid levels predicted unfavourable gout outcomes after 2 years.

Community‐based interventions to reduce sugar intake in healthy populations: A systematic review

This study aimed to assess community‐based interventions to decrease sugar intake among healthy people. According to PRISMA guidelines, in this systematic review, databases including PubMed/MEDLINE, Scopus, EMBASE, Cochrane Library, Web of Science, ProQuest, and Google Scholar were searched up to August 2021. Randomized clinical trials or quasi‐experimental studies reporting the effect of community‐based interventions to reduce sugar intake in general population were included. The quality of eligible studies was assessed using The Joanna Briggs Institute Critical Appraisal Checklists. Our search strategy resulted in a total of 1384 articles out of which 59 articles were included in the study. Of 59 included studies, 48 studies reported significant decrease in sugar intake or intention to sugar sweetened beverages (SSBs) intake or purchasing SSBs. Of the 48 effective studies, 45 (93.7%) had a low risk of bias. Based on the results of low risk of bias studies, interventions performed in schools, household, and community were effective in reducing sugar intake. Almost all types of interventions (educational, multiple and changing in law) had the same effectiveness on reducing sugar intake. In addition, interventions which had a duration of 24–48 weeks were less successful than the others. Interventions with the repetition span of more than 1 month were less successful than the others. The application of multiple interventions appears to be the most effective approach to reducing sugar intake in healthy populations. However, long‐term and well‐designed future studies in different settings are recommended to confirm these results.

CDER167, a dual inhibitor of URAT1 and GLUT9, is a novel and potent uricosuric candidate for the treatment of hyperuricemia

Urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) are important targets for the development of uric acid-lowering drugs. We previously showed that the flexible linkers of URAT1 inhibitors could enhance their potency. In this study we designed and synthesized CDER167, a novel RDEA3710 analogue, by introducing a linker (methylene) between the naphthalene and pyridine rings to increase flexibility, and characterized its pharmacological and pharmacokinetics properties in vitro and in vivo. We showed that CDER167 exerted dual-target inhibitory effects on both URAT1 and GLUT9: CDER167 concentration-dependently inhibited the uptake of [14C]-uric acid in URAT1-expressing HEK293 cells with an IC50 value of 2.08 ± 0.31 μM, which was similar to that of RDEA3170 (its IC50 value was 1.47 ± 0.23 μM). Using site-directed mutagenesis, we demonstrated that CDER167 might interact with URAT1 at S35 and F365. In GLUT9-expressing HEK293T cells, CDER167 concentration-dependently inhibited GLUT9 with an IC50 value of 91.55 ± 15.28 μM, whereas RDEA3170 at 100 μM had no effect on GLUT9. In potassium oxonate-induced hyperuricemic mice, oral administration of CDER167 (10 mg·kg-1 · d-1) for 7 days was more effective in lowering uric acid in blood and significantly promoted uric acid excretion in urine as compared with RDEA3170 (20 mg·kg-1 · d-1) administered. The animal experiment proved the safety of CDER167. In addition, CDER167 displayed better bioavailability than RDEA3170, better metabolic stability and no hERG toxicity at 100 μM. These results suggest that CDER167 deserves further investigation as a candidate antihyperuricemic drug targeting URAT1 and GLUT9.

GOUT AND THE CENTRAL ASIAN DIET

Patients with gout are advised to follow a certain diet. The search for healthy eating habits continues. This overview aims to explore the impact of the Central Asian diet on the development and course of hyperuricemia and gout and to propose related preventive measures. We processed English articles reflecting on the impact of the Central Asian diet on the development of gout and the frequency of gout attacks. Central Asian dishes such as lagman, pilaf, and manty are distinguished for high nutritional value and abundance of saturated fats, red meat, and trans fats. Moderate consumption of Central Asian traditional dishes is advisable to prevent weight gain and gout attacks. Patients with gout are additionally encouraged to consume low-calorie and non-fat products and regularly intake fruits and vegetables during meals. Patients with gout should be provided with information about a healthy diet and lifestyle. More evidence-based studies are warranted to provide better quality guidance on gout prevention and treatment.

Association between consumption of ultra-processed foods and hyperuricemia: TCLSIH prospective cohort study

BACKGROUND AND AIMS

Emerging evidence suggests that consumption of ultra-processed foods (UPF) plays a role in the development of chronic diseases, but evidence of their influence on hyperuricemia is limited. We therefore designed a cohort study to examine whether UPF consumption increase the risk of hyperuricemia in adults.

METHODS AND RESULTS

This was a prospective study (n = 18,444) performed in Tianjin, China from 2013 to 2019. Participants that were aged 18 years and over and with no history of hyperuricemia, were followed up for 1-6 years (median follow-up duration = 4.2 years). UPF consumption was assessed by a validated semi-quantitative food frequency questionnaire. Hyperuricemia was defined as serum uric acid levels ≥7.0 mg/dL in males and ≥ 6 mg/dL in females. Multivariable Cox proportional hazards regression models were used to assess the association between UPF consumption and the risk of hyperuricemia. Restricted cubic spline regression was used to estimate the dose-response association between UPF consumption and risk of hyperuricemia. During follow-up period, the incidence of hyperuricemia was 20.3% in general population (27.7% in males and 13.2% in females). In the final multivariate models, the hazard ratios (95% confidence interval) for hyperuricemia across energy adjusted UPF consumption quartiles were 1.00 (reference), 1.04 (0.94, 1.14), 1.11 (1.01, 1.23), 1.16 (1.05, 1.28) (p for trend = 0.02) in general population.

CONCLUSIONS

This population-based prospective cohort study suggests that increased consumption of UPF is independently associated the risk of hyperuricemia.

Differences in Clinical and Dietary Characteristics, Serum Adipokine Levels, and Metabolomic Profiles between Early- and Late-Onset Gout

This study aimed to identify differences in clinical and dietary characteristics, serum adipokine levels, and metabolomic profiles between early- and late-onset gout. Eighty-three men with gout were divided into an early-onset group (n = 38, aged < 40 years) and a late-onset group (n = 45, aged ≥ 40 years). Dietary and clinical information was obtained at baseline. Serum adipokines, including adiponectin, resistin, leptin, and plasminogen activator inhibitor-1 (PAI-1), were quantified by a Luminex multiplex immunoassay. Metabolite expression levels in plasma were measured in 22 representative samples using metabolomics analysis based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Average body mass index, rate of consumption of sugar-sweetened beverages, and serum uric acid levels were significantly higher in the early-onset group (p < 0.05), as was the PAI-I concentration (105.01 ± 42.45 ng/mL vs. 83.76 ± 31.16 ng/mL, p = 0.013). Changes in levels of metabolites mostly involved those related to lipid metabolism. In the early-onset group, acylcarnitine analog and propylparaben levels were downregulated and negatively correlated with the PAI-1 concentration whereas LPC (22:6) and LPC (18:0) levels were upregulated and positively correlated with the PAI-1 concentration. Dietary and clinical features, serum adipokine concentrations, and metabolites differed according to whether the gout is early-onset or late-onset. The mechanisms of gout may differ between these groups and require different treatment approaches.

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.

Sucrose-Sweetened Drinks Reduce the Physical Performance and Increase the Cardiovascular Risk in Physically Active Males

INTRODUCTION

The intake of sugar-sweetened beverages (SSBs) has increased rapidly, but the effects of this habit on health and physical performance are unknown. This study assessed the effect of excessive SSB intake on biochemical, physical performance, and biochemical and cardiovascular parameters of physically active males.

METHODS

Seventeen volunteers consumed a placebo drink (Pd; carbohydrate free) and an excessive SSB drink (eSSBd = Pd plus 300 g sucrose). In a blind randomized crossover study, the subjects were assigned to Pd or eSSBd groups for 15 days. After an interval of 7 days, subjects were reassigned to the other condition.

RESULTS

After eSSBd intake, there was an increase in weight (69.34 ± 13.71 vs. 70.62 ± 14.06), body mass index (24.49 ± 4.01 vs. 24.97 ± 4.13), waist circumference (75.33 ± 11.22 vs. 76.79 ± 11.51), VLDL (19.54 ± 9.50 vs. 25.52 ± 11.18), triglycerides (78.94 ± 23.79 vs. 114.77 ± 43.65), and peak systolic blood pressure (178.57 ± 26.56 vs. 200.71 ± 24.64). The cardiorespiratory response to exercise (VO2max) (48.15 ± 10.42 vs. 40.98 ± 11.20), peak heart rate (186.64 ± 8.00 vs. 179.64 ± 6.28), total exercise time (15.02 ± 1.57 vs. 14.00 ± 2.18), and mechanical work (15.83 ± 4.53 vs. 13.68 ± 5.67) decreased after eSSBd intake (all values expressed in initial mean ± DP vs. final). The rates of perceived exertion were higher (1.300 vs.1.661 slope and -0.7186 vs. -1.118 y-intercept) after eSSBd intake.

CONCLUSION

The present study shows that 15 days of eSSBd intake may negatively modulate biochemical parameters associated with cardiovascular risk. In addition, this overintake can impair the physical performance and cardiovascular responses to physical exercise.

Acute effect of green tea catechins on uric acid metabolism after alcohol ingestion in Japanese men

INTRODUCTION/OBJECTIVES

Alcohol consumption is associated with hyperuricemia and gout. Previous studies have indicated a role for green tea catechins in uric acid (UA) metabolism. This study aimed to elucidate the acute effect of green tea catechins in terms of enhancing urinary excretion of UA and xanthine/hypoxanthine (Xa/HX; UA precursors) after alcohol ingestion.

METHODS

In a randomized crossover study, ten healthy Japanese subjects consumed test meals, including a Japanese distilled spirit (Shōchū) with water (SW) or Shōchū with catechin-rich green tea (SC), each containing 20 g of alcohol. The SC contained 617 mg of catechin in total. Serum and urine UA and Xa/HX concentrations were measured. Blood samples were collected after 2.5 h, and urine samples were collected between 0 and 5 h after consuming the test meal.

RESULTS

Urine UA and Xa/HX excretions were significantly higher in the SC group than in the SW group (UA: SW, 0.45 ± 0.08; SC, 0.52 ± 0.09; Xa/HX: SW, 0.08 ± 0.04; SC, 0.16 ± 0.05 mg/kg/h). UA clearance (C_UA) and fractional UA excretion (FE_UA) tended to increase more in the SC group than in the SW group (C_UA: SW, 7.76 ± 2.14; SC, 8.75 ± 2.23 mL/min/1.73 m²; FE_UA: SW, 6.08 ± 1.36; SC, 6.64 ± 1.42%). No significant differences in serum UA and Xa/HX concentrations were observed between two groups.

CONCLUSIONS

It was concluded that green tea catechins can enhance the excretion of UA and Xa/HX, even though alcohol is ingested.

TRIAL REGISTRATION NUMBER

UMIN000040076. Retrospectively registered 7 April 2020. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000045687 Key Points • Green tea catechins enhance the excretion of uric acid and xanthine/hypoxanthine, even when alcohol is ingested simultaneously. • In case of non-adherence of limiting alcohol intake, catechin-rich green tea may be an effective dietary component to continue dietary therapy.

Age difference in the combined effect of soda drinks consumption and body adiposity on hyperuricaemia in US adults

OBJECTIVE

To evaluate age-related differences in the independent/combined association of added sugar intake from soda and body adiposity with hyperuricaemia in gender-stratified US adults.

DESIGN

Consumption of added sugar from soda was calculated from 24-h dietary interviews and categorised into none, regular and excessive consumption. Hyperuricaemia was defined as serum uric acid levels >417 mmol/l in men and >357 mmol/l in women. Multiple regression models with interaction terms and logistic models adjusted for covariates were conducted under survey-data modules.

SETTING

National Health and Nutrition Examination Survey during 2007-2016.

PARTICIPANTS

15 338 adults without gout, failing kidneys, an estimated glomerular filtration rate < 30 or diabetes were selected.

RESULTS

The age-stratified prevalence rate of hyperuricaemia was 18·8-20·4 % in males and 6·8-17·3 % in females. Hyperuricaemia prevalence of approximately 50 % was observed in young and middle age males who consumed excessive added sugar from soda. Excessive added sugar intake was observed to be associated with 1·5- to 2·0-fold and 2·0- to 2·3-fold increased risk of the probability of hyperuricaemia in young and middle age males and middle age females, respectively. Study participants, regardless of age or gender, who were obese and consumed excessive added sugar from soda had the highest risk of having hyperuricaemia.

CONCLUSIONS

Our study revealed that the association between hyperuricaemia and consumption of excessive added sugar from soda may vary by age and gender. Obese adults who consumed excessive added sugar from soda had the highest risk of hyperuricaemia, a finding that was found across all age-specific groups for both genders.

Effect of body mass index on serum urate and renal uric acid handling responses to an oral inosine load: experimental intervention study in healthy volunteers

Background

High body mass index (BMI) is strongly associated with hyperuricaemia. It is unknown whether overweight and obesity influences serum urate primarily through increased urate production or reduced renal clearance of uric acid. The aim of this study was to determine the influence of BMI on the response to inosine, a purine nucleoside that functions as an intermediate in the purine salvage and degradation pathways.

Methods

Following an overnight fast, 100 healthy participants without gout attended a study visit. Blood and urine samples were taken prior to and over 180 min after 1.5 g oral inosine. Serum urate and fractional excretion of uric acid (FEUA) were analysed according to high BMI (≥ 25 kg/m²) and low/normal BMI (< 25 kg/m²) groups, and according to BMI as a continuous variable.

Results

Participants in the high BMI group (n = 52, mean BMI 30.8 kg/m²) had higher serum urate concentrations at baseline (P = 0.002) compared to those with low/normal BMI (mean BMI 21.8 kg/m²). However, the high BMI group had a smaller increase in serum urate following the inosine load (P = 0.0012). The two BMI groups had a similar FEUA at baseline (P = 0.995), but those in the high BMI group had a smaller increase in FEUA following the inosine (P = 0.0003). Similar findings were observed when analysing BMI as a continuous variable. Those with high BMI had a smaller increase in FEUA per increase in serum urate, compared to those with low BMI (P = 0.005).

Conclusions

In a fasting state, people with high BMI have elevated serum urate levels but similar FEUA values compared with those with low/normal BMI. Following a purine load, those with high BMI have an attenuated renal excretion of uric acid. These data, using an experimental method to dynamically assess human urate handling, suggest that people with high BMI have a higher renal capacity for uric acid reabsorption when fasted and following a dietary purine intake have reduced renal clearance.

Trial registration

Australia and New Zealand Clinical Trials Registry, ACTRN12615001302549, date of registration 30 November 2015.

Sugar-containing carbonated beverages consumption is associated with hyperuricemia in general adults: A cross-sectional study

BACKGROUND AND AIMS

Research evidence supports a positive link between sugar-containing soft beverages and hyperuricemia. However, data thus far are mostly from Caucasian populations. And in sugar-containing soft beverages overall, sugar-containing carbonated beverages are purchased most often. Therefore, we investigated whether the high consumption of sugar-containing carbonated beverages was associated with the prevalence of hyperuricemia among adults in China.

METHODS AND RESULTS

A cross-sectional study was conducted with 25,507 adults (13,013 men and 12,494 women) in Tianjin, China. Sugar-containing carbonated beverages intake was assessed by a validated semi-quantitative food frequency questionnaire. Hyperuricemia was defined as serum uric acid levels ≥7.0 mg/dL in men and ≥ 6 mg/dL in women. The association between carbonated beverages consumption and hyperuricemia was assessed by multiple logistic regression analysis. The prevalence of hyperuricemia in men and women was 23.4% and 8.2%, respectively. After adjustments for potential confounding factors, the odds ratios (95% confidence interval) for hyperuricemia across sugar-containing carbonated beverages consumption were 1.00 (reference) for almost never, 1.18 (1.05, 1.32) for <1-3 cups/week, 1.49 (1.25, 1.77) for ≥4 cups/week in men (P for trend < 0.005) and 1.11 (0.91, 1.34) for <1-3 cups/week (P for trend = 0.27), 1.70 (1.23, 2.31) for ≥4 cups/week in women (P for trend < 0.001), respectively.

CONCLUSIONS

This cross-sectional survey demonstrated that increased consumption of sugar-containing carbonated beverages is associated with hyperuricemia among adults in China. Restricted sugar-containing carbonated beverages intake might be beneficial to the prevention of hyperuricemia in the general population.

Construction and expression of recombinant uricase‑expressing genetically engineered bacteria and its application in rat model of hyperuricemia

At present, the treatment of hyperuricemia is designed primarily to decrease the production of uric acid using xanthine oxidase inhibitors; however, the therapeutic effect is not satisfactory. Therefore, the key to the successful treatment of hyperuricemia is to increase the excretion of uric acid. The aim of present study was to construct uricase-expressing genetically engineered bacteria and analyze the effects of these engineered bacteria on the lowering of uric acid levels in a rat model of hyperuricemia. The uricase expression vector was constructed by gene recombination technology and transfected into Escherichia coli. The expression and activity of uricase were analyzed by SDS-PAGE analysis and Bradford assay. The water consumption, food intake, body weight, eosinophil count and intestinal histology, in addition to the levels of serum uric acid (SUA) and allantoin in the feces of the rats, were assessed. The intestinal contents of the rats were analyzed by 16S rDNA sequencing technology. The results demonstrated that uricase-expressing genetically engineered bacteria secreted active uricase. All rats exhibited a natural growth trend during the entire experiment, and the SUA of hyperuricemic rats treated with uricase-expressing engineered bacteria was significantly decreased. In conclusion, these results indicate that uricase secreted by recombinant uricase-expressing genetically engineered bacteria served an important role in decreasing SUA levels in a rat model of hyperuricemia.

Population-specific factors associated with fractional excretion of uric acid

BACKGROUND

Reduced renal clearance of uric acid is a major contributor to hyperuricemia. The aim of this study was to examine clinical and genetic variables associated with fractional excretion of uric acid (FEUA).

METHODS

Participants (with and without gout) in the Genetics of Gout in Aotearoa study with available genotyping and FEUA data were included (n = 1713). Ten FEUA-associated loci detected within a genome-wide association study for serum urate in a European population were analysed. A polygenic score for FEUA was calculated in each ancestry group to model the cumulative effects of the genetic variants on FEUA. Associations between FEUA and both clinical variables and polygenic score were tested using linear regression models.

RESULTS

The mean (SD) FEUA was 5.13 (2.70) % in Eastern Polynesian participants, 4.70 (5.89) % in Western Polynesian participants, and 5.89 (2.73) % in New Zealand European participants. Although association with FEUA was observed for SLC2A9 rs11942223 in New Zealand European participants (P = 2.39 × 10- 8), this association was not observed in Eastern or Western Polynesian participants. The polygenic score was positively associated with FEUA in all ancestry groups. In New Zealand European participants, body mass index, diuretic use, polygenic score, and male sex were associated with FEUA and explained 22% of FEUA variance in the regression model. In Eastern and Western Polynesian participants, the tested variables explained 10% and 4% of FEUA variance respectively.

CONCLUSIONS

Both clinical and genetic variables contribute to renal clearance of uric acid. SLC2A9 exerts effects on FEUA variance in people of European ancestry, but not in those of Polynesian ancestry. There is a large unexplained variance in FEUA, particularly in people of Polynesian ancestry.

Gout: state of the art after a decade of developments

This review article summarizes the relevant English literature on gout from 2010 through April 2017. It emphasizes that the current epidemiology of gout indicates a rising prevalence worldwide, not only in Western countries but also in Southeast Asia, in close relationship with the obesity and metabolic syndrome epidemics. New pathogenic mechanisms of chronic hyperuricaemia focus on the gut (microbiota, ABCG2 expression) after the kidney. Cardiovascular and renal comorbidities are the key points to consider in terms of management. New imaging tools are available, including US with key features and dual-energy CT rendering it able to reveal deposits of urate crystals. These deposits are now included in new diagnostic and classification criteria. Overall, half of the patients with gout are readily treated with allopurinol, the recommended xanthine oxidase inhibitor (XOI), with prophylaxis for flares with low-dose daily colchicine. The main management issues are related to patient adherence, because gout patients have the lowest rate of medication possession ratio at 1 year, but they also include clinical inertia by physicians, meaning XOI dosage is not titrated according to regular serum uric acid level measurements for targeting serum uric acid levels for uncomplicated (6.0 mg/dl) and complicated gout, or the British Society for Rheumatology recommended target (5.0 mg/dl). Difficult-to-treat gout encompasses polyarticular flares, and mostly patients with comorbidities, renal or heart failure, leading to contraindications or side effects of standard-of-care drugs (colchicine, NSAIDs, oral steroids) for flares; and tophaceous and/or destructive arthropathies, leading to switching between XOIs (febuxostat) or to combining XOI and uricosurics.

Urate and risk of Alzheimer's disease and vascular dementia: A population-based study

INTRODUCTION

Low serum urate (sU) has been suggested to increase the risk of dementia since a reduction might impair antioxidant capacity. On the other hand, high sU is associated with increased cardiovascular risk which might increase the risk of dementia, especially for vascular dementia.

METHODS

In 1968-1969, a population-based sample of 1462 women aged 38 to 60 years was examined and were followed up over 44 years (mean 33.1 years). We examined whether sU (determined in 1968-1969 and 1992-1994) is associated with risk of late-life dementia.

RESULTS

During 44 years of follow-up, a higher sU (per standard deviation of 76.5 μmol/L) was associated with lower risk for dementia (n = 320; hazard ratio [HR] 0.81; confidence interval [CI] 0.72-0.91), Alzheimer's disease (n = 152; HR 0.78; CI 0.66-0.91), and vascular dementia (n = 52; HR 0.66; CI 0.47-0.94).

DISCUSSION

Our findings support the hypothesis that sU has a protective role in the development of dementia, regardless of dementia subtype. This may have important implications in the treatment of dementia and treatment goals for hyperuricemia in patients with gout.

Achievement of Target Serum Uric Acid Levels and Factors Associated with Therapeutic Failure among Japanese Men Treated for Hyperuricemia/Gout

Objective To assess the rate of successfully achieving treatment goals among Japanese men with hyperuricemia/gout and identify factors influencing the success rate. Methods This cross-sectional study, conducted from January to December 2012, examined the serum uric acid (SUA) levels and clinical characteristics of 2,103 men with hyperuricemia/gout selected from an initial population of 136,770 individuals who participated in a workplace health checkup. The success rates (defined as SUA ≤6.0 mg/dL) were calculated, and a multivariate analysis was used to identify factors associated with "therapeutic failure" to achieve target SUA levels. Results The rate of successfully achieving the target SUA level was 37.5%. The body mass index (BMI) was significantly associated with therapeutic failure [25.0≤ Category (C) 2<27.5, adjusted odds ratio (AOR) =1.35; 27.5≤C3<30.0, AOR=1.69; C4 ≥ 30.0, AOR=1.94; relative to C1<25.0]. A significant positive association was also observed between waist circumference (WC) and therapeutic failure (85≤C2<90, OR=1.29; 90≤C3<95, OR=1.41; 95≤C4, OR=2.28; relative to C1<85.0 cm). Those with higher BMI/WC measurements were significantly more likely to have higher SUA levels than those with lower such measurements. The ongoing intake of dyslipidemia medication was identified as a protective factor against therapeutic failure. Discussion Our findings suggest a possible association between obesity and therapeutic failure, underscoring the importance of maintaining lipid profiles as part of managing SUA levels. Better management of both obesity and dyslipidemia may prevent future cardiovascular disorders by ensuring healthier SUA levels.

Consumption of sugar sweetened beverages and dietary fructose in relation to risk of gout and hyperuricemia: a systematic review and meta-analysis

Background: Findings on the association of sugar sweetened beverages (SSB) and fructose intakes with gout and hyperuricemia have been conflicting.Objective: We aimed to perform a systematic review and meta-analysis on studies that examined the association of SSB and fructose consumption with gout and hyperuricemia in adults.Methods: We searched PubMed, Scopus and Google Scholar up to Aug 2017 for all relevant published papers assessing SSB and fructose intakes and risk of gout and hyperuricemia. After excluding non-relevant papers, 10 studies remained in our systematic. Meta-analysis on SSB consumption and risk of gout was done on three effect sizes from cohort studies and five effect sizes from case-control studies. For risk of hyperuricemia, the meta-analysis was done on six effect sizes from cross-sectional studies. All analyses were performed on ORs or RRs.Results: We found an overall significant positive association between SSB consumption and risk of gout in both cohort (summary effect size: 1.35; 95% CI: 1.18-1.55) and case-control studies (summary effect size: 1.33; 95% CI: 1.06-1.66). Meta-analysis on cross-sectional studies revealed that SSB consumption was associated with 35% greater odds of hyperuricemia (summary effect size: 1.35; 95% CI: 1.19-1.52). No evidence of between-study heterogeneity as well as publication bias was found. Although the studies on fructose intake and risk of gout and hyperuricemia were included in our systematic review, we did not perform met-analysis on these studies due to insufficient number of publications.Conclusion: We found that SSB consumption was significantly associated with increased risk of gout and hyperuricemia in adult population. Further studies are needed to examine the association between dietary fructose intake and risk of gout and hyepruricemia.