Prevalence of gout and hyperuricemia in the US general population: the National Health and Nutrition Examination Survey 2007-2008

Single and combined effect of bisphenol A with high sucrose diet on the diabetic and renal tubular dysfunction phenotypes in Drosophila melanogaster

In the present study, effect of exposure of bisphenol A (BPA) and combined exposure of BPA + HSD has been investigated on the glucose homeostasis and associated renal complications in Drosophila. Exposure of 1.0 mM BPA alone induced type 2 diabetes like condition (T2D) in adult male D. melanogaster via oxidative stress. Elevated TGF-β signaling was evident by increased expression of baboon (babo) in BPA exposed organism that stimulated the modulation of extracellular matrix (ECM) component collagen IV resulting in the fibrosis of the Malpighian tubules (MTs). Combined exposure of BPA + HSD (high sucrose diet) resulted in the increased magnitude of T2D and MTs dysfunction parameters. Taken together, the study illustrates that BPA has diabetogenic potential in exposed Drosophila that caused adverse effects on their MTs and combined exposure with BPA and HSD could aggravate the renal tubular dysfunction. The study further suggests the use of Drosophila model to study the environmental chemicals induced diabetes mediated renal dysfunction.

Spinal gout diagnosed by dual-energy CT: A case report

Axial gout is an atypical presentation of gout caused by monosodium urate deposition in the axial skeleton. Spinal gout presents nonspecifically and can be a difficult diagnosis. The diagnosis of gout is a clinical one, with imaging and labs providing supporting evidence. Current imaging modalities such as magnetic resonance, computed tomography, and X-ray can be nonspecific and lead to invasive procedures for diagnosis. Dual-energy computed tomography allows clear visualization of urate collection and is a valuable tool to make a confident diagnosis of spinal gout. Here, we present a case of a man with longstanding severe gout in which dual-energy computed tomography played a key role in diagnosis.

Hyperuricemia and gout: effects on bone and articular cartilage (literature review)

Gout is a disease characterized by deposition of sodium monourate crystals in tissues which is the reason of inflammation among persons with hyperuricemia (HU). The prevalence of HU, which can be considered the first stage of gout formation, varies in different countries. Despite this, only a small number of persons with HU have been shown to develop symptoms of gout. Recent data suggest that HU is an independent risk factor for cartilage and bone damage. UA, both in the form of crystals and in a dissolved form, activates damage and potentiates cell death by releasing reactive oxygen species, activating the necroptosis pathway, neutrophil traps, synthesis of pro-inflammatory cytokines, and other pathogenetic mechanisms that cause the negative effects of HU and gout on articular cartilage and subchondral bone. The association of HU and osteoarthritis (OA) is well known and based on the common pathogenesis, but the direction of this relationship is still a debatable issue. The accumulated data suggest the need for a deeper study of the relationship of gout and asymptomatic HU with pathological processes leading to the development and progression of OA and disorders of bone metabolism.

Association between nutrient patterns and hyperuricemia: mediation analysis involving obesity indicators in the NHANES

Background

Diet has long been hypothesized to play an important role in hyperuricemia, and weight gain is a factor that is strongly associated with the rise in serum urate. We aimed to clarify the mediating role of obesity in the relationship between diet and hyperuricemia and to determine whether a weight-loss diet is an effective way to prevent hyperuricemia.

Methods

This cross-sectional study analysed representative samples of United States (n = 20,081; NHANES 2007–2016) adults. Nutrient patterns were derived with two methods: principal component analysis (PCA) and reduced rank regression (RRR) with obesity. Logistic regression and multivariable linear regression were applied to analyse the association between nutrient patterns in obesity and hyperuricemia. Mediation analyses were used to determine whether four obesity indicators, including body mass index (BMI), waist circumference (WC), visceral adiposity index (VAI) and lipid accumulation product index (LAP), mediated the relationship between nutrient patterns and hyperuricemia.

Results

PCA revealed three nutrient patterns (including “Low energy diet”, “Lower vitamin A, C, K pattern” and “Vitamin B group”), and only Vitamin B group had a total effect on hyperuricemia. RRR revealed one main nutrient pattern associated with obesity, which was characterized by High fat and low vitamin levels and was significantly associated with hyperuricemia. Mediation analysis showed that obesity mostly or even completely mediated the relationship between nutrient patterns and hyperuricemia, especially traditional obesity indicators, which played a key intermediary effect. The proportions of indirect effects for BMI and WC were as high as 53.34 and 59.69, respectively.

Conclusions

Our findings suggest that the direct effect of diet on hyperuricemia is weak, and obesity plays a critical mediating role in the relationship between diet and hyperuricemia, which confirms that a weight-loss diet such as a “Low fat and high vitamin diet” may be useful in preventing hyperuricemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14357-5.

The visceral and liver fat are significantly associated with the prevalence of hyperuricemia among middle age and elderly people: A cross-sectional study in Chongqing, China

Background

The prevalence of hyperuricemia (HUA) has been increasing in recent years. HUA is a crucial risk factor for gout and an independent risk factor for cardiovascular diseases (CVDs). Identifying potentially modifiable factors of HUA is vital for preventing gout and even CVDs. This study aimed to explore the associations of fat distribution with HUA among middle-aged and elderly people in Chongqing, China.

Materials and methods

A cross-sectional study was conducted between July 2020 and September 2021. People who underwent quantitative computed tomography (QCT) scans were invited to participate in the study. A total of 3,683 individuals whose clinical characteristics and QCT-based fat distribution measurements included visceral fat area (VFA), subcutaneous fat area (SFA), and liver fat content (LFC) were well-recorded were included. HUA was defined as having a serum uric acid level greater than 420.0 μmol/L. Multivariate logistic regression models were used to evaluate the association between these adipose variables and HUA prevalence.

Results

The HUA prevalence was 25.6% (943/3,683), which was 39.6% (817/2,063) in men and 7.8% (126/1,620) in women. In the fully adjusted model (model 4), the comparison of the highest one with the lowest quartiles of adipose variables showed that the multivariable OR (95% confidence intervals) of HUA were 2.08 (1.36-3.16; P for trend = 0.001) for VFA, 0.89 (0.63-1.25; P for trend = 0.651) for SFA, and 1.83 (1.42-2.34; P for trend < 0.0001) for LFC. For VFA, the association was more evident in men than in women.

Conclusion

Higher VFA and LFC were significantly associated with the increased prevalence of HUA in middle-aged and elderly Chinese individuals. VFA and LFC may have a predictive effect on HUA. Controlling visceral and liver fat accumulation may be beneficial for middle-aged and older people. HUA can be prevented with specific effective healthy physical activity and balanced diet guidelines.

Trend dynamics of gout prevalence among the Chinese population, 1990-2019: A joinpoint and age-period-cohort analysis

Background

The burden of gout is increasing worldwide, which places a heavy burden on society and healthcare systems. This study investigates the independent effects of age, period, and cohort on the gout prevalence from 1990 to 2019 in China, compares these effects by gender and then predicts the future burden of gout over the next decade.

Methods

The data were obtained from the Global Burden of Disease (GBD) study in 2019. Joinpoint regression model was employed to calculate the annual percentage change (APC) in gout prevalence, and the age-period-cohort analysis was utilized to estimate the independent effects of age, period, and cohort. ARIMA model was extended to predict the gout epidemic in 2020-2029.

Results

In 2019, there were 16.2 million cases of gout in China, with an age-standardized prevalence rate (ASPR) of 12.3‰ and 3.9‰ in men and women, respectively. During 1990-2019, the ASPR of gout was increasing significantly, with an average APC of 0.9%. The periods of 2014-2017 and 2001-2005 were "joinpoint" for men and women (APC: 6.3 and 5.6%). The age-period-cohort analyses revealed that the relative risk (RR) of developing gout increased with age, peaking at 70-74 years in men (RR_age(70-74) = 162.9) and 75-79 years in women (RR_age(75-79)=142.3). The period effect trended upward, with a more rapid increase in women (RR_period(2019) = 2.31) than men (RR_period(2019) = 2.23). The cohort effect generally peaked in the earlier cohort born in 1905-1909 for both sexes. Gout prevalence showed a strong positive correlation with the consumption of meat and aquatic products (r_meat = 0.966, r_{aquaticproducts} = 0.953). Within 2029, the ASPR of gout was projected to be 11.7‰ and 4.0‰ in men and women, respectively.

Conclusion

The prevalence of gout is increasing at an alarming rate in China; thus, it is necessary to provide targeted health education, regular screening, and accessible urate-lowering therapy healthcare to prevent and protect against gout in China, particularly in older women.

Polygenic risk score trend and new variants on chromosome 1 are associated with male gout in genome-wide association study

Background

Gout is a highly hereditary disease, but not all those carrying well-known risk variants have developing gout attack even in hyperuricemia status. We performed a genome-wide association study (GWAS) and polygenic risk score (PRS) analysis to illustrate the new genetic architectures of gout and asymptomatic hyperuricemia (AH).

Methods

GWAS was performed to identify variants associated with gout/AH compared with normouricemia. The participants were males, enrolled from the Taiwan Biobank and China Medical University, and divided into discovery (n=39,594) and replication (n=891) cohorts for GWAS. For PRS analysis, the discovery cohort was grouped as base (n=21,814) and target (n=17,780) cohorts, and the score was estimated by grouping the polymorphisms into protective or not for the phenotypes in the base cohort.

Results

The genes ABCG2 and SLC2A9 were found as the major genetic factors governing gouty and AH, and even in those carrying the rs2231142 (ABCG2) wild-genotype. Surprisingly, variants on chromosome 1, such as rs7546668 (DNAJC16), rs10927807 (AGMAT), rs9286836 (NUDT17), rs4971100 (TRIM46), rs4072037 (MUC1), and rs2974935 (MTX1), showed significant associations with gout in both discovery and replication cohorts (all p-values < 1e−8). Concerning the PRS, the rates of gout and AH increased with increased quartile PRS in those SNPs having risk effects on the phenotypes; on the contrary, gout/AH rates decreased with increased quartile PRS in those protective SNPs.

Conclusions

We found new variants on chromosome 1 significantly relating to gout, and PRS predicts the risk of developing gout/AH more robustly based on the SNPs’ effect types on the trait.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02917-4.

The Prevalence of Hyperuricemia and Its Correlates among Adults in China: Results from CNHS 2015-2017

This study aimed to investigate the prevalence of hyperuricemia (HUA) and associated risk factors in Chinese adults aged 18 to 59 years. All the data were collected from the China Nutrition and Health Surveillance during the period 2015–2017, which adopted a stratified, multistage, random sampling method on a national scale. A total of 52,627 participants aged 18 years or older were included in this study. The definition of hyperuricemia was 420 μmol/L for male and 360 μmol/L for female. The Rao–Scott chi-square test was used to compare the differences in prevalence between or among the subgroups. A weighted two-level multivariate survey-logistic regression was used to detect the correlations between HUA and demographic, physical, lifestyle and metabolic factors. The total prevalence of HUA was 15.1%, and that was higher in male, current smokers, higher BMI and less physical activities subgroups, and also in noninfectious chronic diseases (NCDs) subgroups. The subgroups of non-vegetarian diet, insufficient vegetable intakes and excessive red meat and alcohol intakes had significantly higher HUA prevalence. After introducing all the variables in the survey-logistic regression, gender, age, BMI, physically active, hypertension, diabetes mellitus, bean and nut intake, vegetable intake, red meat intake, alcohol consumption and vegetarian were associated with HUA. Among the significant variables, age and physical active served as a protective factor, and BMI showed to be a risk factor for HUA. Hypertension and dyslipidemia could increase the risk for HUA, while diabetes mellitus was shown a negative association with it. For dietary factors, vegetarian diet, sufficient beans and nuts and vegetables intake could lower the risk of HUA, but more alcohol could increase the risk of HUA. Dietary factor played a key role in HUA. It suggested that the intervention of dietary factor should receive more attention to ameliorate the high prevalence of HUA in China.

POP1 inhibits MSU-induced inflammasome activation and ameliorates gout

Canonical inflammasomes are innate immune protein scaffolds that enable the activation of inflammatory caspase-1, and subsequently the processing and release of interleukin (IL)-1β, IL-18, and danger signals, as well as the induction of pyroptotic cell death. Inflammasome assembly and activation occurs in response to sensing of infectious, sterile and self-derived molecular patterns by cytosolic pattern recognition receptors, including the Nod-like receptor NLRP3. While these responses are essential for host defense, excessive and uncontrolled NLRP3 inflammasome responses cause and contribute to a wide spectrum of inflammatory diseases, including gout. A key step in NLRP3 inflammasome assembly is the sequentially nucleated polymerization of Pyrin domain (PYD)- and caspase recruitment domain (CARD)-containing inflammasome components. NLRP3 triggers polymerization of the adaptor protein ASC through PYD-PYD interactions, but ASC polymerization then proceeds in a self-perpetuating manner and represents a point of no return, which culminates in the activation of caspase-1 by induced proximity. In humans, small PYD-only proteins (POPs) lacking an effector domain regulate this key process through competitive binding, but limited information exists on their physiological role during health and disease. Here we demonstrate that POP1 expression in macrophages is sufficient to dampen MSU crystal-mediated inflammatory responses in animal models of gout. Whether MSU crystals are administered into a subcutaneous airpouch or into the ankle joint, the presence of POP1 significantly reduces neutrophil infiltration. Also, airpouch exudates have much reduced IL-1β and ASC, which are typical pro-inflammatory indicators that can also be detected in synovial fluids of gout patients. Exogenous expression of POP1 in mouse and human macrophages also blocks MSU crystal-induced NLRP3 inflammasome assembly, resulting in reduced IL-1β and IL-18 secretion. Conversely, reduced POP1 expression in human macrophages enhances IL-1β secretion. We further determined that the mechanism for the POP1-mediated inhibition of NLRP3 inflammasome activation is through its interference with the crucial NLRP3 and ASC interaction within the inflammasome complex. Strikingly, administration of an engineered cell permeable version of POP1 was able to ameliorate MSU crystal-mediated inflammation in vivo, as measured by neutrophil infiltration. Overall, we demonstrate that POP1 may play a crucial role in regulating inflammatory responses in gout.

Research Progress on the Relationship between Dietary Patterns and Hyperuricemia

As the final metabolite of purine metabolism, uric acid is critically associated with human health. The serum uric acid level is regulated by diet and the metabolic capacity of the human body. The impaired control of uric acid metabolism and excretion is associated with the increased level of serum uric acid, which ultimately results in hyperuricemia. Hyperuricemia is the "fourth-highest" after hypertension, hyperglycemia, and hyperlipidemia. With progress made in the relationship between diet and hyperuricemia, different dietary patterns and lifestyles have been discussed, such as exercise, the amount intake of meat, seafood, supplements with omega-3 fatty acids, sugar-sweetened soft drinks and energy drinks, and lower-fat-containing foods as well as drinking beer, wine, and spirits in the present article. This study demonstrated that a lower risk of hyperuricemia is substantially correlated with higher baseline adherence to MeDiet, and plant polyphenols can combat hyperuricemia by blocking xanthine oxidase.

Profiling of Serum Oxylipins Identifies Distinct Spectrums and Potential Biomarkers in Young People with Very Early Onset Gout

Objective

Oxylipins modulate inflammation via complex pathways. The oxylipin profile in gout remains unexplored. In this study, we systemically profiled oxylipins in young men and identified new oxylipin biomarkers for clinical use in differentiating gout from hyperuricemia.

Methods

Oxylipin profiling was performed in 90 men (30 very early onset gout, 30 asymptomatic HU (HU) and 30 normouricemia (NU), all aged &lt;20 years) divided into discovery and validation sample sets. The dataset was analyzed based on orthogonal projection to latent structure-discriminant analysis (OPLS-DA). Correlation network and pathway enrichment were conducted to reveal potential oxylipin-involved pathways of gout. Candidate oxylipins were further evaluated and optimized in the validation cohort, and differential oxylipin biomarkers combined with or without serum urate were applied to construct diagnosis models.

Results

In discovery stage 21 differential oxylipins between the gout vs HU comparisons and 14 differential oxylipins between the gout vs NU comparisons were discovered. Correlation network analysis was performed and 14(S)-HDHA（14S-hydroxy-4Z, 7Z, 10Z, 12E, 16Z, 19Z-docosahexaenoic acid）was identified as a hub metabolite in both comparisons. Seven down-regulated oxylipins in gout vs HU group and five down-regulated oxylipins in gout vs NU group were validated. Diagnostic models were constructed with the above oxylipins, with 14(S)-HDHA alone acquiring area under the curve (AUC) 1 (95%CI, 1–1) in both comparisons.

Conclusion

Young men with very early onset gout have distinct oxylipin spectrums, especially those derived from AA (arachidonic acid), EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Differential oxylipins could serve as candidate serum biomarkers in differentiating gout from hyperuricemia.

Detection and Treatment of Hyperuricemia in Clinical Practice (According to the PROFILE Outpatient Registry)

Aim. To study the frequency of detection of hyperuricemia (HU) in patients with high and very high cardiovascular risk and the frequency of prescribing drugs that lower serum uric acid (sUA) levels in real clinical practice.

Material and methods: The general information of the study was based on the data of 2457 patients who were consistently included in the «PROFILE» registry until November 30, 2020: 1250 men (50.9%) and 1207 (49.1%) women. All patients with HU were selected (UA level ≥360 pmol/l in women, ≥420 pmol/l in men). At the stage of inclusion of the patient, data on MC indicators were available in 1777 (72.3%), upon re-examination - only 262 (33.2%) out of 790 patients who returned to the appointment.

Results: The most common study of the level of sUA was performed in patients with gout (65.2%), with arterial hypertension (AH) and dyslipemia in 29.1% of cases, with diabetes mellitus (DM) - 30.1%, with impaired tolerance to glucose (IGT) - 40.2%, with other diseases, the proportion of patients with a known UA was even less. A positive relationship was found between the presence of AH and IGT with the frequency of UA control (p<0.001). In patients with AH, an increase in the level of sUA was detected significantly more often than in patients without AH (p<0.001), and less frequently in patients with DM and IGT (p<0.001 and p<0.01, respectively). The frequency of allopurinol prescribing was low: 49 (2%) patients received therapy, while of the 284 patients with HU, only 20 (7%) were prescribed allopurinol.

Conclusion: in real clinical practice, only 29.1% of patients with AH and 20-25% of patients with other CVDs were monitored for sUA levels, every third patient had data on sUA levels at a repeat visit. In the presence of gout, the proportion of patients with current UA was higher (65%). For those with AH and IGT, positive correlations were found between the presence of the disease and control of sUA levels. A low frequency of prescribing drugs for the correction of HU was revealed.

Ulcerated Tophaceous Gout

Gout is a disease that occurs in response to the presence of monosodium urate (MSU) crystals typically within joints. Patients with gout may develop a chronic deposition of monosodium urate crystals within or around joints, cartilage, tendons, peri-articular, and subcutaneous tissue. This condition is termed “tophaceous gout.” Ulceration of the skin by tophi is very uncommon. Literature regarding the clinical course and the management of ulcerated tophi is limited and, therefore, treatment options are not well established. We hereby present a case of a 46-year-old male who presented to our facility with poorly controlled polyarticular tophaceous gout complicated by ulcerated tophi. Our hope is to contribute to the limited knowledge of this rare disease process and to contribute toward formulating the best management approach.

Serum uric acid is a predictive biomarker of incident metabolic syndrome at the Brazilian longitudinal study of adult Health (ELSA - Brasil)

AIM

To investigate whether serum uric acid (SUA) levels and hyperuricemia can be predictive biomarkers of incident metabolic syndrome(MS) among different body mass index(BMI) categories, and to investigate SUA cutoffs that best discriminate individuals with incident MS.

METHODS

We analyzed 7,789 participants without MS at baseline of ELSA-Brasil study. Logistic regression models were performed to evaluate associations between incident MS and SUA levels/hyperuricemia, expressed by odds ratios(ORs) and confidence intervals(95 % CI).

RESULTS

We found 1,646 incident MS cases after a median follow-up of 3.8[3.5-4.1] years. Incident MS was present among 8.3 % (n = 290) of participants with normal weight, 28.3 % (n = 850) with overweight, 39.8 % (n = 506) with obesity. Among incident MS participants of total sample, 33.0 % had hyperuricemia [SUA > 6.0 mg/dL (356.9 μmol/L)]. After all adjustments, SUA was independently prognostic of incident MS: for each 1 mg/dL increase in SUA the odds of incident MS were 45 % higher (OR1.45[CI95 %1.34-1.55 p <.01]). Associations were found for those presenting normal weight, overweight and obesity (OR1.43[CI95 %1.31-1.57 p <.01; OR1.22[CI95 %1.13-1.32 p <.01]; and OR1.16[CI95 %1.04-1.29 p <.05]) respectively. Hyperuricemia was independently associated with incident MS (OR1.88[CI95 %1.49-0.2.36 p <.01]). The SUA cut point level maximizing sensitivity and specificity in the discrimination of incident MS was 5.0 mg/dL.

CONCLUSIONS

SUA level is an independent predictive biomarker of incident MS at all BMI categories.

Association between mixed dioxin exposure and hyperuricemia in U.S. adults: A comparison of three statistical models

BACKGROUND

Previous studies on the relationship between dioxin exposures and hyperuricemia have usually been based on multi-chemical linear models. However, the complex nonlinear relationship and interaction between mixed dioxin exposures and hyperuricemia have seldom been studied. In this study, we applied three different statistical models to assess the joint effect of 12 dioxins on hyperuricemia.

METHODS

A total of 7 dioxin-like polychlorinated biphenyls (DL-PCBs), 3 polychlorinated dibenzo-p-dioxins (PCDDs), and 2 polychlorinated dibenzofurans (PCDFs) were measured in the serum of adults by the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2004. We fitted multivariable logistic regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) models to estimate the association of individual and mixed dioxin exposures with hyperuricemia.

RESULTS

Among the 1008 individuals included in our analysis, 20.04% had hyperuricemia. In the multivariable logistic regression established for each single dioxin, PCB28, PCB74, PCB105, PCB118, and 1,2,3,4,6,7,8-HPCDD were positively associated with hyperuricemia. With including all dioxins in the multivariable logistic regression model simultaneously, only PCB28 and 1,2,3,4,6,7,8-HPCDD were positively associated with hyperuricemia. In the WQS regression model, the WQS index was significantly associated (OR (95% CI): 2.32 (1.26, 4.28)) with hyperuricemia, and 1,2,3,4,6,7,8-HPCDD (weighted 0.22) had the largest contribution. In BKMR analysis, a significant positive association was found between mixed dioxin exposure and hyperuricemia when all dioxins were at their 60th percentile or above, compared to their 50th percentile. The univariate exposure-response function showed that PCB105 and PCB118 were positively associated with hyperuricemia.

CONCLUSION

By comparing the three statistical models, we concluded that the whole-body burden of 12 dioxins was significantly positively associated with hyperuricemia. PCB105, PCB118, and 1,2,3,4,6,7,8-HPCDD played the most important roles in hyperuricemia.

Changes in the prevalence of hyperuricemia in clients of health examination in Eastern China, 2009 to 2019

BACKGROUND

With the continuous improvement of people's living standards, the incidence of hyperuricemia (HUA) is increasing globally. The prevalence of HUA ranged in terms of region, race, and age. This study aims to investigate the changes in the prevalence of HUA in clients of health examination in Eastern China between 2009 and 2019.

METHODS

Chinese men and women aged 20-79 years (n = 4847 in the 2009 group and n = 12,188 in 2019 group) who had received health examinations were enrolled. Serum uric acid (UA) levels and biochemical parameters, including fasting blood-glucose (FBG), triglyceride (TG), total cholesterol (CHOL), high-density lipoprotein (HDL), low-density lipoprotein (LDL), creatinine (Cr) and blood urea nitrogen (BUN) were evaluated. The prevalence of HUA in different age groups were measured, and the correlation of biochemical parameters with HUA were analyzed.

RESULTS

The prevalence of HUA was 18.7% in the 2019 group, which was significantly higher than that in 2009 (11.1%). In females, the prevalence of HUA was significantly higher in 2019 than 2009 for age groups of 20-29 and 30-39 years. In male population, 2019 participants had significantly higher age-specific prevalence for all age groups than 2009 participants. Young men aged 20-29 years became the main population of HUA in the 2019 participants, whereas middle-aged men aged 40-49 years had the highest prevalence of HUA in the 2009 participants. The prevalence rates of HUA in all BMI groups in 2019 participants were significantly higher than those in 2009 participants. Spearmen's correlation analysis and Logistic regression analysis indicated that BMI was positively correlated with HUA. The receiver-operating characteristic curve (ROC) analysis showed BMI > 24.48 kg/m2 and BMI > 23.84 kg/m2 displayed good capacities to discriminate the population with HUA from those without HUA in 2009 and 2019 participants, respectively.

CONCLUSIONS

In recent 10 years, the prevalence of HUA was increased rapidly in Chinese adults, especially in males. In 2019, the young male group (20-29 years old) replaced the middle-aged male group (40-49 years old) in 2009 as the leading age group for male HUA. BMI was positively correlated with HUA, and might be a potential risk factors to predict HUA.

Hyperuricemia is Associated with the Presence of Metabolically Obese Normal-Weight and Metabolically Healthy Obese Phenotypes

BACKGROUND

It is well-recognized that hyperuricemia is a common abnormality among individuals with metabolic syndrome.

AIMS

The objective of this study was to determine whether hyperuricemia is associated with the metabolically obese normal-weight (MONW) and metabolically healthy obese (MHO) phenotypes.

METHODS

Men and women equal or greater than 18 years of age were enrolled in a cross-sectional study. Normal-weight subjects were allocated into the MONW or healthy normal-weight (HNW) groups; while obese individuals were divided into the MHO and metabolically unhealthy obese (MUO) subgroups. MONW phenotype was defined by body mass index (BMI) <25.0 kg/m² accompanied by at least one cardiovascular risk factor (hyperglycemia, elevated blood pressure, hypertriglyceridemia, and low high-density lipoprotein cholesterol), and MHO phenotype was considered in obese subjects (BMI ≥30 kg/m²) without metabolic abnormalities.

RESULTS

A total of 567 individuals were enrolled; of them, normal-weight subjects were allocated into the MONW (n = 101) and control (n = 72) groups, whereas obese individuals into the MHO (n = 61) and MUO (n = 333) groups. The multiple logistic regression analysis adjusted by age, gender, and body mass index revealed that hyperuricemia is significantly associated with MONW (OR = 5.14; 95% CI: 1.37-19.29) and MHO (OR = 0.34; 95% CI: 0.14-0.82) phenotypes.

CONCLUSION

Results of our study showed that hyperuricemia is associated with both MONW and MHO phenotypes.

Caffeic acid phenethyl ester alleviated hypouricemia in hyperuricemic mice through inhibiting XOD and up-regulating OAT3

BACKGROUND

Hyperuricemia is characterized with high serum uric acids (SUAs) and directly causes suffering gout. Caffeic acid phenethyl ester (CAPE) is widely included in dietary plants and especially propolis of honey hives.

HYPOTHESIS/PURPOSE

Since CAPE exerts a property resembling a redox shuttle, the hypothesis is that it may suppress xanthine oxidase (XOD) and alleviate hyperuricemia. The aim is to unveil the hypouricemic effect of CAPE and the underlying mechanisms.

METHODS

By establishing a hyperuricemic model with potassium oxonate (PO) and hypoxanthine (HX) together, we investigated the hypouricecmic effect of CAPE. On this model, the expressions of key mRNAs and proteins, including glucose transporter 9 (GLUT9) and urate transporter 1 (URAT1), and the activity of XOD were assayed in vivo. Also, the inhibitory effect of CAPE against XOD was assayed in vitro through enzymatic activity tests and by molecular docking.

RESULTS

CAPE demonstrated a remarkable hypouricemic effect, which reduced the SUAs of hyperuricemic mice (401 ± 111 µmol/l) to 209 ± 56, 204 ± 65 and 154 ± 40 µmol/l (p < 0.01) at the doses of 15, 30 and 60 mg/kg respectively, depicting efficacies between 48 and 62% and approaching allopurinol's efficacy (52%). Serum parameters, body weights, inner organ coefficients, and H&E staining suggested that CAPE displayed no general toxicity and it alleviated the liver and kidney injuries caused by hyperuricemia. Mechanistically, CAPE decreased XOD activities significantly in vivo, presented an IC₅₀ at 214.57 µM in vitro and depicted a favorable binding to XOD in molecular simulation, indicating that inhibiting XOD may be an underlying mechanism of CAPE against hyperuricemia. CAPE did decreased GLUT9 protein and down-regulated URAT1 mRNA and protein. In addition, CAPE up-regulated ATP binding cassette subfamily G member 2 (ABCG2) and organic anion transporter 3 (OAT3) mRNA and proteins in comparison with that of the hyperuricemic control. All above, CAPE may alleviate hyperuricmia through inhibiting XOD, decreasing GLUT9 and URAT1 and increasing ABCG2 and OAT3.

CONCLUSION

CAPE presented potent hypouricemic effect in hyperuricemic mice through inhibiting XOD activity and up-regulating OAT3. CAPE may be a promising treatment against hyperuricemia.

A fly GWAS for purine metabolites identifies human FAM214 homolog medusa, which acts in a conserved manner to enhance hyperuricemia-driven pathologies by modulating purine metabolism and the inflammatory response

Elevated serum urate (hyperuricemia) promotes crystalline monosodium urate tissue deposits and gout, with associated inflammation and increased mortality. To identify modifiers of uric acid pathologies, we performed a fly Genome-Wide Association Study (GWAS) on purine metabolites using the Drosophila Genetic Reference Panel strains. We tested the candidate genes using the Drosophila melanogaster model of hyperuricemia and uric acid crystallization ("concretion formation") in the kidney-like Malpighian tubule. Medusa (mda) activity increased urate levels and inflammatory response programming. Conversely, whole-body mda knockdown decreased purine synthesis precursor phosphoribosyl pyrophosphate, uric acid, and guanosine levels; limited formation of aggregated uric acid concretions; and was sufficient to rescue lifespan reduction in the fly hyperuricemia and gout model. Levels of mda homolog FAM214A were elevated in inflammatory M1- and reduced in anti-inflammatory M2-differentiated mouse bone marrow macrophages, and influenced intracellular uric acid levels in human HepG2 transformed hepatocytes. In conclusion, mda/FAM214A acts in a conserved manner to regulate purine metabolism, promotes disease driven by hyperuricemia and associated tissue inflammation, and provides a potential novel target for uric acid-driven pathologies.

Monosodium urate crystals with controlled shape and aspect ratio for elucidating the pathological progress of acute gout

Gout is a self-limiting inflammatory arthritis mediated by the precipitation of monosodium urate (MSU) crystals that further activate the NLRP3 inflammasome and initiate a cascade of inflammatory events. However, the key physicochemical properties of MSU crystals that determine the acute phase of gout have not been fully identified. In this study, a library of engineered MSU crystals with well-controlled size and shape is designed to explore their proinflammatory potentials in mediating the pathological progress of gout. It is demonstrated that medium-sized long aspect ratio MSU crystals induce more prominent IL-1β production in vitro due to enhanced cellular uptake and the production of mitochondrial reactive oxygen species (mtROS). The characteristics of MSU crystals are also correlated with their inflammatory potentials in both acute peritonitis and arthritis models. Furthermore, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) is demonstrated to inhibit MSU-induced oxidative burst by removing plasma membrane cholesterol. As a result, it attenuates the inflammatory responses both in vitro and in vivo. Additionally, antioxidant N-acetylcysteine (NAC) is shown to alleviate acute gouty symptom by suppressing oxidative stress. This study identifies the key physicochemical properties of MSU crystals that mediate the pathogenesis of gout, which sheds light on novel design strategies for the intervention of gout.

A glance into the future of gout

Gout is characterized by monosodium urate (MSU) crystal deposits in and within joints. These deposits result from persistent hyperuricaemia and most typically lead to recurrent acute inflammatory episodes (gout flares). Even though some aspects of gout are well characterized, uncertainties remain; this upcoming decade should provide further insights into many of these uncertainties. Synovial fluid analysis allows for the identification of MSU crystals and unequivocal diagnosis. Non-invasive methods for diagnosis are being explored, such as Raman spectroscopy and imaging modalities. Both ultrasound and dual-energy computed tomography (DECT) allow the detection of MSU crystals; this not only provides a mean of diagnosis, but also has furthered gout knowledge defining the presence of a preclinical deposition in asymptomatic hyperuricaemia. Scientific consensus establishes the beginning of gout as the beginning of symptoms (usually the first flare), but the concept is currently under review. For effective long-term gout management, the main goal is to promote crystal dissolution treatment by reducing serum urate below 6 mg/dL (or 5 mg/dL if faster crystal dissolution is required). Current urate-lowering therapies' (ULTs) options are limited, with allopurinol and febuxostat being widely available, and probenecid, benzbromarone, and pegloticase available in some regions. New xanthine oxidase inhibitors and, especially, uricosurics inhibiting urate transporter URAT1 are under development; it is probable that the new decade will see a welcomed increase in the gout therapeutic armamentarium. Cardiovascular and renal comorbidities are common in gout patients. Studies determining whether optimal treatment of gout will positively impact these comorbidities are currently lacking, but will hopefully be forthcoming. Overall, the single change that will most impact gout management is greater uptake of international rheumatology society recommendations. Innovative strategies, such as nurse-led interventions based on these recommendations have recently demonstrated treatment success for people with gout.

The Association Between Spicy Food Intake and Risk of Hyperuricemia Among Chinese Adults

Hyperuricemia is associated with substantial health and economic burden all over the world. Dietary habits are an important influencing factor of hyperuricemia. This study aimed to investigate the relationship between spicy food intake and hyperuricemia based on a large population. A total of 22,125 individuals aged 30-79 were enrolled in China Multi-Ethnic Cohort (CMEC), Chongqing region. Spicy food intake information was collected by a standardized questionnaire. The association between spicy food intake and hyperuricemia was estimated by multivariable logistic regression models and multiple linear regression models. Additionally, we explored these relations in subgroups stratified by sex and age. Furthermore, sensitivity analyses were conducted to verify the stability of current findings. After controlling for potential confounders, compared with participants who never consumed spicy food and consumed less hot, participants who ate 3-5 days per week and very hot had the highest risk of hyperuricemia; the ORs (95% CIs) were 1.28 (1.09, 1.5) and 1.22 (0.92, 1.63), respectively. Additionally, the corresponding ORs (95% CIs) for each level increment in the frequency and degree of pungency in spicy food intake were 1.04 (1.01, 1.07) (P trend = 0.009) and 1.15 (1.04, 1.26) (P trend = 0.004). Further in sex-stratified and age-stratified analysis, similar positive associations were observed among men and those aged 30-59, but no significant association was found among women and those aged 60-79. In the linear regression models, 3-5 days per week and moderate pungency in spicy food intake were associated with 5.21 μmol/L (95% CI: 1.72, 8.70) and 4.69 μmol/L (95% CI: 1.93, 7.45) higher serum urate level. Results in further subgroup analysis were generally consistent with the logistic regression models. This study suggests that spicy food intake may be a risk factor for hyperuricemia, especially in men and younger people, and more studies are warranted to verify the causal associations.

Serum Uric Acid Levels and Nonalcoholic Fatty Liver Disease: A 2-Sample Bidirectional Mendelian Randomization Study

BACKGROUND

Observational studies have shown that nonalcoholic fatty liver disease (NAFLD) is highly correlated with serum uric acid (SUA). However, these studies have an inherent risk of bias due to reverse causality. Here, we perform a Mendelian randomization (MR) study to investigate causality between SUA and NAFLD.

METHODS

We performed a 2-sample bidirectional MR analysis using summary-level data from genome-wide association studies of SUA (with up to 110 347 individuals) and NAFLD (1483 cases and 17781 controls) in European populations. First, 13 single nucleotide polymorphisms (SNPs) associated with SUA were selected as instruments to estimate the causal effect of elevated SUA levels on the risk of NAFLD using the inverse-variance weighted (IVW) method. Then we performed MR with 3 SNPs as genetic instruments for NAFLD. To test the reliability, further sensitivity analyses were also conducted.

RESULTS

Our MR analyses demonstrated that NAFLD was associated with SUA levels (β = 0.032, P = 0.003). Similar results were obtained using other MR methods and in sensitivity analyses. Genetic predisposition to elevated SUA levels was not associated with NAFLD (IVW MR, odds ratio = 1.02, 95% CI: 0.90-1.15, P = 0.775). Similar results were obtained using other 4 pleiotropy robust MR methods and in sensitivity analyses, excluding 9 SNPs associated with potential confounders.

CONCLUSIONS

Our study supports the causal increased SUA levels by NAFLD, while our study does not confirm a causal association for SUA levels on risk of NAFLD. Further study is needed to interpret the potential mechanisms.

The reality of treatment for hyperuricemia and gout in Japan: A historical cohort study using health insurance claims data

Hyperuricemia causes gout and has also been associated with metabolic syndrome and cardiovascular disease. Uric acid‐lowering drugs (ULDs) are used to reduce uric acid levels for the treatment of hyperuricemia and gout. However, there is a lack of robust and real‐world data on the history and treatment of patients with newly diagnosed hyperuricemia or gout in Japan. This retrospective, longitudinal, historical cohort study determined the characteristics of patients with hyperuricemia and/or gout, and prescription of, and adherence to, ULDs using data from the JMDC Claims Database. The primary evaluation population included 64 677 patients with newly diagnosed hyperuricemia and/or gout. Of these, only 26 501 (41.0%) had a prescription for ULDs at diagnosis. Even when ULDs were prescribed, the persistence rate of prescriptions declined over time, with a 54.4% persistence rate for ULDs at 12 months after the index diagnosis. In subgroups of patients with or without hypertension and diabetes, the rate of ULD prescription continuation was significantly higher in those with comorbidities than in those without (76.8% vs. 42.6% in those with vs. without hypertension, and 78.7% vs. 52.2% in those with vs. without diabetes). These finding suggest that therapeutic interventions to lower serum uric acid levels are under‐utilized for patients with newly diagnosed hyperuricemia and/or gout in Japan.

2022 update of the Austrian Society of Rheumatology and Rehabilitation nutrition and lifestyle recommendations for patients with gout and hyperuricemia

Background

Gout is the most frequent inflammatory joint disease in the western world and has a proven genetic background. Additionally, lifestyle factors like increasing life span and wealth, sufficient to excess nutritional status and a growing prevalence of obesity in the population, as well as e.g. alcohol consumption contribute to the rising incidence of hyperuricemia and gout. Apart from an adequate medication, medical advice on nutrition and lifestyle is an essential part of the management of gout patients, being at high risk of internal comorbidities.

Objective

In 2015, the ÖGR (Österreichische Gesellschaft für Rheumatologie und Rehabilitation) working group for osteoarthritis and crystal arthropathies already published nutrition and lifestyle recommendations for patients with gout and hyperuricemia. Since then, a multitude of literature has been published addressing this topic, what required an update.

Methods

First, the authors performed a hierarchical literature search to screen the meanwhile published literature. Also considering references of the first publication, the relevant literature was selected, and the 2015 recommendations were either kept as published, reformulated or newly produced. Finally, the evidence level and the level of agreement with each recommendation were added.

Results

Following this process, ten recommendations were generated instead of the initial nine. Like in the original publication, a colored icon presentation was provided to complement the written text.

Conclusion

The Austrian nutrition and lifestyle recommendations for patients with gout and hyperuricemia were updated incorporating the most recent relevant literature, serving as education material for patients and updated information for physicians.

Febuxostat Improves Uric Acid Levels and Renal Function in Patients with Chronic Kidney Disease and Hyperuricemia: A Meta-Analysis

Background. Uric acid nephropathy, also known as hyperuricemia nephropathy or gouty nephropathy, is characterized by uric acid crystal deposition and inflammatory cell infiltration. Herein, we aimed to demonstrate the role of febuxostat on uric acid levels and renal function in patients with chronic kidney disease and hyperuricemia. Methods. Eight databases included were searched for clinical randomized controlled trials. Meanwhile, the confidence interval (CI) of either relative risk or mean difference was set to 95%. Besides, the heterogeneity of the research results is tested by $I^2$ . Results. Ten studies were ultimately included in this meta-analysis. All of them were considered to be random controlled trials. 10 studies reported the serum uric acid of the test group and the control group, which was significantly lower (SMD: -146.44, 95% Cl: -195.96, -86.93, and $P<0.01$ ) than the control group, EGFR (SMD: 3.21, 95% Cl: 1.17, 5.25, and $P<0.01$ ), serum creatinine (SMD: -15.27, 95% Cl: -20.75, -9.79, and $P<0.01$ ), serum urea nitrogen (SMD: -2.37, 95% Cl: -3.31, -1.61, and $P<0.01$ ), and adverse reactions (OR: 0.74, 95% Cl: 0.32, 1.68, and $P=0.47$ ). Conclusion. The results of this study suggest that febuxostat may be effective in patients with CKD with HUA, as evidenced by serum uric acid, creatinine, urea nitrogen, and EGFR. However, large sample, multicenter, low risk of bias clinical studies, as well as basic medical research, are needed.

Prevalence and risk factors of hyperuricemia and gout: a cross-sectional survey from 31 provinces in mainland China

Background and Objetives

Hyperuricemia (HUA) and gout seriously influence patients’ quality of life. The current study was performed to investigate the prevalence of HUA and gout and the related risk factors in Chinese adults.

Methods

Data were collected from the National Survey of Thyroid Disorders and Diabetes (the Thyroid Disease, Iodine Status, and Diabetes National Epidemiological survey [TIDE]), a cross-sectional investigation conducted during 2015–2017. Using a random, multistage, and stratified sampling strategy, a representative sample (78,130 participants aged 18 years and above) was selected from the general population in 31 provinces of mainland China. The weighted prevalence rates of HUA and gout were calculated, and the related risk factors were analyzed.

Results

The weighted prevalence rates of HUA and gout in Chinese adults were 17.7% and 3.2%, respectively. The prevalence of HUA in males linearly decreased with age, while the prevalence in females showed the opposite trend (both P for trend < 0.01). The prevalence rate of gout exhibited a rising tendency with age in both genders (both P for trend < 0.05). The HUA and gout prevalence rates in males were the highest in Han and Tibetan nationalities, respectively. Logistic regression analysis showed that the morbidities of HUA and gout were differentially associated with age, residence location, nationality, smoking, and other complicating metabolic diseases in the two genders.

Conclusions

There are relatively high prevalence rates of gout and HUA in China, which is currently a developing country. Reducing their burden has become an urgent issue for Chinese people.

Change in serum urate level with urate-lowering therapy initiation associates in the immediate term with patient-reported outcomes in people with gout

OBJECTIVE

To examine the associations of changes in serum urate (SU) with health-related quality of life (HRQOL) in gout.

METHODS

We used the first 6-months of data from four interventional trials and one observational, open-label study of urate-lowering therapy (ULT) use. HRQOL were assessed at baseline and every 3-months, and SU was measured monthly. Primary outcome measures were Short-form 36 physical and mental component summary scores, Health Assessment Questionnaire Disability Index (HAQ-DI), Sheehan Disability Scale (SDS), Patient Global Assessment, and pain scores in the last week. Linear mixed models for each outcome were adjusted as appropriate for current SU, change in urate in the last month, number of flare-affected days in the last month, baseline BMI, age, comorbidities, sex, ethnicity, trial/study and treatment combination, and tophi status (fixed effects); subject, and the trial/study month were random effects.

RESULTS

Higher current SU correlated with reduced physical and mental HRQOL, and increased SDS and pain but not with HAQ-DI score. In the first 6-months of new/escalating ULT use, absolute change in SU levels associated with poorer outcomes on the HAQ-DI scale (β (95% CI) = 0.013 (0.007-0.019)) and poorer outcomes on SDS, SF-36 MCS, patient global and pain scales. Reduction of SU associated with poorer outcomes in all six measures.

CONCLUSION

High SU levels were associated with poorer HRQOL, pain and Sheehan disability score. Recent SU level fluctuations are associated with poorer outcomes, primarily driven by a reduction in SU. Clinical emphasis on slow rather than fast SU reduction and the routine use of effective, anti-inflammatory medications at ULT initiation/escalation may avoid short-term poor outcomes.

Risk Factors for Postsurgical Gout Flares after Thoracolumbar Spine Surgeries

Gouty arthritis is the most common form of inflammatory arthritis and flares frequently after surgeries. Such flares impede early patient mobilization and lengthen hospital stays; however, little has been reported on gout flares after spinal procedures. This study reviewed a database of 6439 adult patients who underwent thoracolumbar spine surgery between January 2009 and June 2021, and 128 patients who had a history of gouty arthritis were included. Baseline characteristics and operative details were compared between the flare-up and no-flare groups. Multivariate logistic regression was used to analyze predictors and construct a predictive model of postoperative flares. This model was validated using a receiver operating characteristic (ROC) curve analysis. Fifty-six patients (43.8%) had postsurgical gout flares. Multivariate analysis identified gout medication use (odds ratio [OR], 0.32; 95% confidence interval [CI], 0.14−0.75; p = 0.009), smoking (OR, 3.23; 95% CI, 1.34−7.80; p = 0.009), preoperative hemoglobin level (OR, 0.68; 95% CI, 0.53−0.87; p = 0.002), and hemoglobin drop (OR, 1.93; 95% CI, 1.25−2.96; p = 0.003) as predictors for postsurgical flare. The area under the ROC curve was 0.801 (95% CI, 0.717−0.877; p < 0.001). The optimal cut-off point of probability greater than 0.453 predicted gout flare with a sensitivity of 76.8% and specificity of 73.2%. The prediction model may help identify patients at an increased risk of gout flare.

Association between Dietary Fat Intake and Hyperuricemia in Men with Chronic Kidney Disease

Despite a close relationship between chronic kidney disease (CKD) and uric acid level, few studies have examined the relationship between uric acid level and fat intake by kidney function status. Therefore, we investigated the association between dietary fat intake and hyperuricemia with and without decreased kidney function in males living in Shika Town, Ishikawa Prefecture, Japan. This study included 361 males with a mean age of 60.7 years. Dietary fat and fatty acid intakes were evaluated using the brief-type self-administered diet history questionnaire. Reduced kidney function was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, while hyperuricemia was defined as a serum uric acid level >7.0 mg/dL. A two-way analysis of covariance showed that saturated fatty acid (p = 0.026), monounsaturated fatty acid (p = 0.014), and polyunsaturated fatty acid (p = 0.022) were significantly lower in the high uric acid group than in the normal uric acid group. In multiple logistic analysis stratified by renal function, lipid intake was negatively associated with hyperuricemia in the low eGFR group. These findings suggest that higher dietary lipid/fatty acid intake may be effective in the prevention and treatment of hyperuricemia in men with CKD.

Efficacy and safety of urate-lowering agents in asymptomatic hyperuricemia: systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Asymptomatic hyperuricemia was found to be associated with increased cardiovascular disease risk but the potential benefits of urate-lowering therapy (ULT) remain controversial. We conducted a systematic review and network meta-analysis (NMA) with frequentist model to estimate the efficacy and safety of ULT in asymptomatic hyperuricemia.

METHODS

MEDLINE, Embase, and Scopus were searched without language restrictions. Randomized controlled trials (RCT) of adults with asymptomatic hyperuricemia were eligible if they compared any pair of ULTs (i.e., allopurinol, febuxostat, probenecid, benzbromarone, sulfinpyrazone, rasburicase, lesinurad, and topiroxostat) and placebo or no ULT, and had outcomes of interest, including composite renal events, major adverse cardiovascular events, serum urate levels, estimated glomerular filtration rate (eGFR), systolic blood pressure, and adverse events.

RESULTS

NMA with frequentist approach was applied to estimate relative treatment effects, i.e., risk ratio (RR) and mean difference (MD). A total of 23 RCTs were eligible. NMA identified beneficial effects of ULT on composite renal events and eGFR but not for other outcomes. Allopurinol and febuxostat had significantly lower composite renal events than placebo (RR 0.39, 95% confidence interval [CI] 0.23 to 0.66, and RR 0.68, 95% CI 0.46 to 0.99, respectively). Both treatments also resulted in significantly higher eGFR than placebo (MD 3.69 ml/min/1.73 m², 95% CI 1.31 to 6.08, and MD 2.89 ml/min/1.73 m², 95% CI 0.69 to 5.09, respectively). No evidence of inconsistency was identified.

CONCLUSIONS

Evidence suggests that allopurinol and febuxostat are the ULTs of choice in reducing composite renal events and improving renal function.

TRIAL REGISTRATION

This study was registered with PROSPERO: CRD42019145908. The date of the first registration was 12^th November 2019.

Hypouricemic effect of 2,4-dihydroxybenzoic acid methyl ester in hyperuricemic mice through inhibiting XOD and down-regulating URAT1

In this paper, we reported the hypouricemic effect of 2,4-dihydroxybenzoic acid methyl ester (DAE), a component of Ganoderma applanatum, in hyperuricemic mice through inhibiting XOD and down-regulating URAT1. Computationally, DAE showed a high similarity to allopurinol and depicted a high affinity in docking to XOD. In vitro, DAE exhibited an inhibitory effect against XOD. Importantly, DAE demonstrated a remarkable hypouricemic effect, decreasing serum uric acids (SUAs) of hyperuricemic mice (407 ± 31 μmol/L) to 195 ± 23, 145 ± 33 and 134 ± 16 μmol/L (P < 0.01) at the doses of 20, 40, and 80 mg/kg with a dose-dependent manner and showing efficacies at 54-68 %, which were close to the efficacies of allopurinol (61 %) and benzbromarone (57 %). DAE depicted higher and negatively dose-independent urinary uric acids in comparison with that of the hyperuricemic control, implying DAE exerted an uricosuric effect and also a reduction effect on uric acid production. Unlike toxic allopurinol and benzbromarone, no general toxicity on body weights and no negative influence on liver, kidney, spleen and thymus were observed for DAE. Mechanistically, DAE inhibited XOD activities in vivo. Moreover, DAE up-regulated OAT1 and down-regulated GLUT9, URAT1 and CNT2. Overall, DAE may present a hypouricemic effect through inhibiting XOD and up-regulating OAT1 and down-regulating GLUT9, URAT1 and CNT2. This work provided novel insights into the hypouricemic effect of DAE and G. applanatum.

Effects of secukinumab and adalimumab on serum uric acid level in patients with plaque psoriasis

BACKGROUND

Psoriasis is a chronic systemic inflammatory disease, and hyperuricemia is a common comorbidity in patients with psoriasis. However, there are limited reports on the relationship between serum uric acid levels and biological treatment efficacy. The purposes of this study were to compare the differences in serum uric acid levels between patients with psoriasis and healthy controls and analyze the risk of hyperuricemia.

METHODS

A total of 196 patients with psoriasis and 191 age- and sex-matched healthy controls were enrolled in this retrospective cohort study. One hundred and twenty-seven patients with severe psoriasis were treated with biologics. Sixty-eight patients received adalimumab, and 59 patients received secukinumab. Serum uric acid levels were measured at baseline, week 24, and week 48 of treatment.

RESULTS

Patients with psoriasis had higher serum uric acid levels than healthy controls (6.4 ± 1.7 mg/dL vs. 5.7 ± 1.5 mg/dL, P  < 0.001). Hyperuricemia was found in 33.7% (66/196) of patients with psoriasis, which was significantly higher than that in healthy controls (13.1% [25/191], P  < 0.001). Serum uric acid levels and hyperuricemia were not related to the severity of psoriasis ( P  > 0.05). No significant changes in serum uric acid levels and hyperuricemia were observed following adalimumab treatment ( P  > 0.05). The serum uric acid level in patients treated with secukinumab was 6.7 ± 1.6 mg/dL at week 24, which was not statistically different from that at baseline (6.6 ± 1.4 mg/dL, P  = 0.885). Serum uric acid levels were significantly decreased at week 48 (6.3 ± 1.5 mg/dL vs. 6.6 ± 1.4 mg/dL, P  = 0.007) in patients treated with secukinumab. Secukinumab had no significant effect on hyperuricemia either ( P  > 0.05).

CONCLUSIONS

The serum uric acid levels and prevalence of hyperuricemia in patients with psoriasis were significantly higher than those in healthy controls. Secukinumab treatment for 48 weeks successfully decreased serum uric acid levels in patients with psoriasis, whereas adalimumab had no significant effect on serum uric acid levels.

Early-life exposure to the Chinese famine and risk of hyperuricaemia in adult females in Qingdao

Two population-based cross-sectional surveys involving randomly selected Chinese adults aged 35-74 years were conducted in Qingdao, China in 2006 and 2009. Nine thousand fifty-five subjects from the two surveys were grouped into four birth groups of fetal/infant exposed (born between 1 January 1959 and 31 December 1962), childhood exposed (born between 1 January 1950 and 31 December 1958), adolescence exposed (born between 1 January 1942 and 31 December 1949) and the unexposed (born before 1941 and after 1963). Multivariate logistic regression models were used to calculate the OR and 95 % CI of hyperuricaemia in different exposed groups. Overall, famine exposure in the fetal/infant period, childhood and adolescence was not associated with adulthood hyperuricaemia (all P > 0·05). In females, childhood exposed group (OR = 1·59, 95 % CI 1·25, 2·02) and adolescence exposed group (OR = 1·74, 95 % CI 1·30, 2·33) both had higher risks to have hyperuricaemia in adult. However, this difference was not found in fetal/infant exposed group. In males, no significant relation was observed in any famine exposed group (all P > 0·05). Exposure to famine in childhood and adolescence is associated with an increased risk of hyperuricaemia for adulthood of females, but not in males. Adequate nutrition during early life appears to be beneficial to prevent hyperuricaemia of adult females.

Short Hexapeptide Optimized from Rice-Derived Peptide 1 Shows Promising Anti-hyperuricemia Activities

Plant-derived peptides are a treasure trove for new-generation anti-hyperuricemia drugs. In the current study, we optimized a short hexapeptide rice-derived peptide 1 (RDP1)-M3 (AAAAGA) according to the anti-hyperuricemia RDP1 peptide identified from rice in our previous research. Results showed that RDP1-M3 exerted better hyperuricemia-alleviating and xanthine oxidase (XOD)-inhibiting potency in mice than RDP1. The biodistribution of RDP1-M3 was also analyzed. RDP1-M3 directly decreased XOD and uric acid levels in vivo and in vitro. In addition, RDP1-M3 reduced the expression of urate transporter 1 and glucose transporter 9, increased the level of organic anion transporter 1, reduced the expression of NOD-like receptor superfamily pyrin 3 inflammasomes, and reduced the levels of interleukin-1β and tumor necrosis factor-α of hyperuricemic mice. Thus, our results indicated that the optimized short hexapeptide RDP1-M3 may be a candidate drug for anti-hyperuricemia.

Prevalence and risk factors of hyperuricaemia in non-obese Chinese: a single-centre cross-sectional study

OBJECTIVES

Hyperuricaemia is closely related to metabolic diseases and is receiving increasing attention from all over the world. This study aimed to investigate the prevalence and factors associated with hyperuricaemia in non-obese Chinese population.

DESIGN

Retrospective cross-sectional study.

SETTING

A large general hospital that can provide health check-ups in Hangzhou, China.

PARTICIPANTS

A total of 5731 apparently healthy Chinese adults (2349 men and 3382 women) who took their health check-ups during the year of 2019.

EXCLUSION CRITERIA

(1) those with body mass index ≥24 kg/m2; (2) those with incomplete anthropometric and biochemical data; (3) those with a history of malignancy and (4) those under urate-lowering treatment.

PRIMARY AND SECONDARY OUTCOME MEASURES

The prevalence and factors associated with hyperuricaemia in non-obese Chinese adults.

RESULTS

Of the 5731 non-obese subjects enrolled, 538 (9.4%) were identified as having hyperuricaemia, specifically 16.3% in men and 4.6% in women. The prevalence of hyperuricaemia markedly increased in women aged above 50 years. The prevalence of hyperuricaemia was significantly higher in metabolically unhealthy participants with normal weight than in metabolically healthy participants with normal weight. Participants with hyperuricaemia showed a higher prevalence of metabolic syndrome and fatty liver disease than participants with normouraemia. Age, waist circumference, estimated glomerular filtration rate, blood urea nitrogen, excessive drinking and fatty liver were associated with hyperuricaemia in both genders.

CONCLUSION

The prevalence of hyperuricaemia was 9.4% in non-obese Chinese adults. Non-obese participants with hyperuricaemia also showed multiple metabolic disorders. We suggest that clinicians pay attention to serum uric acid level in non-obese patients.

Prevalence and potential relevance of hyperuricemia in pediatric kidney transplant recipients-a CERTAIN registry analysis

BACKGROUND

Asymptomatic hyperuricemia is frequently observed in pediatric kidney transplant recipients; symptomatic hyperuricemia, however, is a rare complication. Only few data are available in this patient population. We, therefore, investigated the prevalence of hyperuricemia and its association with kidney transplant function and blood pressure in a multicenter cohort of pediatric kidney transplant recipients.

METHODS

This is a retrospective, observational multicenter registry study. All pediatric kidney transplant recipients in the CERTAIN database with at least one documented serum uric acid level and a follow-up of 5 years posttransplant were eligible. We identified 151 patients with 395 measurements of serum uric acid. We calculated the prevalence of hyperuricemia, analyzed potential risk factors and clinical consequences such as elevated blood pressure and reduced estimated glomerular filtration rate (eGFR). Statistical analysis was performed using IBM SPSS Statistics 26.

RESULTS

One hundred and ten of 395 (27.8%) serum uric acid levels were above 416 µmol/L (7.0 mg/dL), defined as the upper limit of normal. Univariate analysis showed a significant (p = .026) inverse association of serum uric acid with eGFR overtime. There was no significant association of serum uric acid concentrations with body mass index (z-score), blood pressure (z-score), or sex. No episodes of gout were documented.

CONCLUSION

This study shows that hyperuricemia is present in a considerable number of patients sometime after pediatric kidney transplantation and is associated with lower eGFR. Whether hyperuricemia contributes to faster decline of graft function or to the overall cardiovascular risk of these patients remains to be elucidated.

Evaluation of renal microperfusion in hyperuricemic nephropathy by Contrast-Enhanced Ultrasound imaging

Diagnostic tools for the early detection of renal injury caused by hyperuricemia are still lacking. Here, we investigated whether contrast-enhanced ultrasound (CEUS) could be used as a diagnostic tool for hyperuricemic nephropathy (HN). In the HN rat model, CEUS detected a significant decline in renal cortical perfusion compared with that in control rats. Peak intensity (PI) values correlated significantly with serum KIM-1 levels and fibrosis scores in HN rats. An early decline in PI values was also observed in chronic kidney disease (CKD) stage 1 patients with HN compared with the controls (61.1±4.52 dB versus 65.80±7.10 dB) and correlated with renal function in the patients with HN. In contrast, an increase in time to reach PI values was detected in HN patients with stage 1 CKD (15.14±1.75 s versus 14.52±4.75 s) and was more pronounced in CKD stage 4 patients (67.32±3.29 s). CEUS was able to detect abnormal renal perfusion in early CKD with HN, which correlated with renal function decline, suggesting that CEUS could be used as a noninvasive tool for assessing renal function in patients with HN.

Clinicopathological Patterns and Outcomes in Patients with Lupus Nephritis and Hyperuricemia

A limited number of large cohort studies have reported the clinicopathological characteristics and prognosis of patients with lupus nephritis (LN) and hyperuricemia (HUA). In this retrospective cohort study, 1297 LN patients were enrolled from January 1996 to December 2011 in the First Affiliated Hospital of Sun Yat-Sen University, and HUA occurred in 649 (50.04%) of these 1297 LN patients. Compared to patients without HUA, those with HUA presented with higher blood pressure and triglyceride levels, lower hemoglobin and serum albumin levels, worse renal function, more severe hematuria and proteinuria, higher lupus activity, and more positive antiphospholipid antibody. Pathologically, HUA cases presented more crescents, a higher degree of mesangial matrix, endothelial cell proliferation, and inflammatory cell infiltration. During the 52-month follow-up, the 5-year and 10-year incidence rates of renal endpoint events were 11.1% and 19.5% in the HUA group, and 8.3% and 13.8% in the non-HUA group, respectively (p = 0.073). In addition, the 5-year and 10-year mortality rates did not differ significantly between the HUA (12.0% and 18.2%) and non-HUA (12.2% and 17.5%) groups, respectively. This study verified that HUA was not an independent risk for poor clinical outcomes, and steroids that delay the deterioration of renal function did not affect the survival of these patients.

Host-Population Microbial Diversity Scaling of Chinese Gut Microbiomes in Gout Patients

Gout is a prevalent chronic inflammatory disease that affects the life of tens of millions of people worldwide, and it typically presents as gout arthritis, gout stone, or even kidney damage. Research has revealed its connection with the gut microbiome, although exact mechanism is still unclear. Studies have shown the decline of microbiome diversity in gout patients and change of microbiome compositions between the gout patients and healthy controls. Nevertheless, how diversity changes across host individuals at a cohort (population) level has not been investigated to the best of our knowledge. Here we apply the diversity-area relationship (DAR), which is an extension to the classic SAR (species-area relationship) and establishes the power-function model between microbiome diversity and the number of individuals within cohort, to comparatively investigate diversity scaling (changes) of gut microbiome in gout patients and healthy controls. The DAR modeling with a study involving 83 subjects (41 gout patients) revealed that the potential number of microbial species in gout patients is only 70% of that in the healthy control (2790 vs 3900) although the difference may not be statistically significant. The other DAR parameters including diversity scaling and similarity parameters did not show statistically significant differences. We postulate that the high resilience of gut microbiome may explain the lack of significant gout-disease effects on gut microbial diversity at the population level. The lack of statistically significant difference between the gout patients and healthy controls at host population (cohort) level is different from the previous findings at individual level in the existing literature.

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

Background

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

Methods

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

Results

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

Conclusion

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

Optimized UV-Spectrophotometric Assay to Screen Bacterial Uricase Activity Using Whole Cell Suspension

Uricase catalyzes the conversion of uric acid into allantoin with concomitant reduction of molecular oxygen to hydrogen peroxide. In humans, uricase is not functional, thereby predisposing individuals to hyperuricemia, a metabolic disturbance associated with gout, chronic kidney disorders, and cardiovascular diseases. The efficacy of current therapies to treat hyperuricemia is limited, and novel approaches are therefore desired, for instance using uricase-expressing probiotic strains. Here, we evaluated UV-spectrophotometric and H₂O₂-based fluorescent assays to enable the rapid identification of uricase activity in a broad panel of lactobacilli, Bacillus, and Bifidobacterium species. We highlighted abiotic (medium composition and mode of sterilization) and biotic (H₂O₂-producing strains) factors impacting the measurements' accuracy, and reported on the stepwise optimization of a simple, fast, and robust high-throughput UV-spectrophotometric method to screen uricase activity using whole bacterial suspension, thereby assessing both cell-associated and extracellular activity. The validity of the optimized assay, based on the monitoring of uric acid degradation at 300 nm, was confirmed via liquid chromatography. Finally, a panel of 319 Qualified Presumption of Safety (QPS) strains of lactobacilli (18 species covering nine genera), Bacillus (three species), and Bifidobacterium (four species) were screened for uricase activity using the optimized method. All 319 strains, but the positive control Bacillus sp. DSM 1306, were uricase-negative, indicating that this activity is rare among these genera, especially in isolates from food or feces. Altogether, the UV-spectrophotometric high-throughput assay based on whole bacterial suspension reported here can be used to rapidly screen large microbial collections, by simultaneously detecting cell-associated and extracellular uricase activity, thereby accelerating the identification of uricolytic strains with therapeutic potential to treat hyperuricemia.

Association of Sedentary Behavior and Physical Activity With Hyperuricemia and Sex Differences: Results From the China Multi-Ethnic Cohort Study

OBJECTIVE

To determine the association of physical activity (PA) and sedentary time (ST; leisure and total ST), commuting mode with hyperuricemia in a multiethnic Chinese population, and to analyze the difference between sexes.

METHODS

Baseline data were analyzed from 22,094 participants from the China Multi-Ethnic Cohort study in the Yunnan region, China. PA and sedentary behavior were assessed through questionnaires. Hyperuricemia was defined as serum urate > 7.0 mg/dL among men and > 6.0 mg/dL among women. A restricted cubic spline (RCS) was created to model the possible nonlinear relationship of PA and ST with hyperuricemia. Logistic regression was used to estimate the odds ratio (OR) and 95% CI.

RESULTS

Hyperuricemia prevalence in the observed population was 15.5% (men 25.5%, women 10.7%). Compared to those with light PA, participants with moderate-to-vigorous PA had lower odds of hyperuricemia (adjusted ORs were 0.85 [95% CI 0.77-0.94] and 0.88 [95% CI 0.79-0.97]). However, RCS showed a U-shaped nonlinear relationship between PA and hyperuricemia, and a linear relationship between hyperuricemia prevalence and increasing ST. Total ST ≥ 4 hours/day increased the risk of hyperuricemia in women but not in men. Mode of transportation revealed that sedentary behavior increased the risk of hyperuricemia, but there were inconsistent results based on sex.

CONCLUSION

Moderate PA may be more beneficial in reducing the risk of hyperuricemia. Reducing ST may have a greater effect on preventing hyperuricemia in females than in males.

Trends in hospital visits and healthcare costs of gout and seropositive rheumatoid arthritis in Korea from 2010 to 2017 using National Healthcare Claims

BACKGROUND/AIMS

We examined temporal trends in the rate of gout and seropositive rheumatoid arthritis (RA) hospital visits and healthcare costs in Korea.

METHODS

We conducted a serial cross-sectional analysis of Korean national healthcare claims. We calculated the annual increase in hospital visits (emergency department [ED] visits, outpatient visits, and hospitalizations) and total healthcare costs per visit.

RESULTS

From 2010 to 2017, the annual rates of ED visits, outpatient visits, and hospitalizations for gout increased from 6.28 to 21, from 638.38 to 1059.55, and from 12.37 to 15.6 per 100,000 persons, respectively. Before 2013, ED visits for gout were most common in patients over 70 years old, but they were most common in those aged between 30 and 49 years after 2013. The number of patients with ED visits, outpatient visits, and hospitalizations for RA from 2010 to 2017 increased from 1.25 to 1.87, from 219.04 to 307.49 and from 8.44 to 12.32 per 100,000 persons, respectively. However, there was no increase in the prevalence of ED visits for RA in any age group except for those older than 70 years. The cost per ED visit for gout significantly decreased from 496.3 to 273.6 US dollar during the study period. There was no significant change in the cost per ED visit for RA between 2010 and 2017.

CONCLUSION

There was a large increase in ED visits for gout during the study period. Further studies are needed to analyze the reason behind increased ED visits for gout and suggest ways on how to improve gout care.

Efficacy of Xanthine Oxidase Inhibitors in Lowering Serum Uric Acid in Chronic Kidney Disease: A Systematic Review and Meta-Analysis

Objective: Current guidelines for gout recommend a treat-to-target approach with serum uric acid (SUA). However, there is little evidence for the dose-dependent effects of urate-lowering therapy (ULT). Herein, we analyzed the reported SUA-lowering effect and SUA target achievement differences for various doses of xanthine oxidase inhibitors. Methods: Approved ULT drugs were selected from the FDA Drug Database. We included prospective randomized controlled trials of ULT drugs from ClinicalTrials.gov, articles published in the journal “Drugs”, and Embase, a literature database. A meta-analysis was performed to determine the ability of different ULT drugs and doses to lower and maintain a target SUA < 6 mg/dL. Results: We identified 35 trials including 8172 patients with a baseline SUA of 8.92 mg/dL. The allopurinol, febuxostat, and topiroxostat showed dose-proportional SUA-lowering responses. Compared with allopurinol 300 mg daily, febuxostat 80 mg daily and 120 mg daily more effectively maintained SUA < 6 mg/dL. Conclusion: Allopurinol, febuxostat, and topiroxostat showed dose-proportional ability to lower and achieve a target SUA < 6 mg/dL. Significance and Innovations. We showed dose-dependent SUA lowering effects of allopurinol, febuxostat, and topiroxostat. Febuxostat is effective at ULT compared to allopurinol and could be potentially offered as an alternative agent when patients (1) have CKD, (2) have the human leukocyte antigen HLA-B*5801 allele, and (3) become refractory to allopurinol. Gradual allopurinol dose increase with a lower starting dose is needed in CKD.

Prevalence of hyperuricemia and the relationship between serum uric acid concentrations and lipid parameters among King Abdulaziz University Hospital patients

Background

Several studies have associated uric acid with dyslipidemia. However, no previous studies have examined patients without chronic illness.

Aim

: The aim of this study is to assess the relationship between serum uric acid concentration and lipid profile parameters and to estimate the prevalence of hyperuricemia in the city of Jeddah.

Patients and Methods

A retrospective study was conducted on 1206 patients who undergone laboratory blood testing over a 3-year period (2018-2020) at King Abdulaziz University Hospital, which was ethically approved. We used a predesigned checklist to collect data from electronic hospital records using Google Forms. Bivariate analysis, tables, and graphs were used to represent and identify the relationships between variables. A P value of <0.05 was considered significant.

Results

Our study revealed a prevalence of 12% for hyperuricemia in the study population. Males were more frequently affected than females (8.13% vs. 3.73%, respectively). There was no association between serum uric acid concentration and lipid profile parameters, including total cholesterol (P = 0.92), triglyceride (P = 0.42), high-density lipoprotein (P = 0.47), and low-density lipoprotein (P = 0.66). There was a strong association between serum uric acid concentration and high body mass index (P < 0.001), older age (P = 0.002), male sex (P < 0.001), and nationality (P < 0.001). Furthermore, there was an association between sex and mean erythrocyte sedimentation rate (P = 0.02) and mean triglyceride concentration (P = 0.02).

Conclusion

We observed a low prevalence of hyperuricemia, and our results indicate no association between serum uric acid concentration and lipid profile parameters.

Serum 25-hydroxyvitamin D might be negatively associated with hyperuricemia in U.S. adults: an analysis of the National Health and Nutrition Examination Survey 2007-2014

PURPOSE

The results of previous studies on the relationship between serum 25-hydroxyvitamin D [25(OH)D] and hyperuricemia are controversial. We hypothesized that serum 25(OH)D concentrations of U.S. adults would negatively correlate with the risk of hyperuricemia.

METHOD

Data came from the National Health and Nutrition Examination Survey 2007-2014 were used, after excluding those who met at least one of the exclusion criteria, a total of 9096 male individuals and 9500 female individuals aged 18 years or older were included. Binary logistic regression analysis and restricted cubic spline with fully adjusted confounding factors were applied to evaluate the association between serum 25(OH)D and hyperuricemia. We further performed stratified analysis and sensitivity analysis to minimize the influence of gender, metabolic syndrome, obesity and renal dysfunction on the above association.

RESULTS

We found a negative correlation between serum 25(OH)D and hyperuricemia. In the binary logistic regression analysis, compared with the highest serum 25(OH)D quartile [Q4: 25(OH)D > 77.10 nmol/L] group, the odds ratios (95% confidence intervals) in the lowest quartile [Q1: 25(OH)D ≤ 43.20 nmol/L] was 1.46 (1.22-1.75) in the fully adjusted model. Restricted cubic spline analysis showed L-shaped and non-linear relationships between 25(OH)D and hyperuricemia. In sensitivity analysis, after restricting to participants without significant renal dysfunction and obesity, the above association remained significant. After restricting to participants who were diagnosed as metabolic syndrome, above association remained significant in the fully adjusted model. In stratified analysis by gender, the association remained significant among males and females.

CONCLUSIONS

Serum 25(OH)D might be inversely associated with hyperuricemia in general U.S. adults. From our study, for people with unexplained hyperuricemia, screening for serum Vitamin D concentration might be necessary.

The Relationship between Alcohol Consumption and Gout: A Mendelian Randomization Study

Gout is a disease that manifests itself after decades of following a high-purine diet, with excessive alcohol consumption assumed to be one of the main contributors to the development of the disease. This study performs a Mendelian randomization (MR) analysis to determine whether alcohol consumption causally affects the risk of developing both hyperuricemia and gout. The results indicate that genetically predicted drinks consumed per week have no causal effect on neither the risk of gout (p = 0.35), nor serum uric acid levels (p = 0.73). For MR analysis in the other direction, genetic risk of gout was significantly associated with drinks per week (p = 0.03). Furthermore, the results of the MR analysis were verified in a cohort of individuals diagnosed with hyperuricemia and gout, comprising of alcohol-consuming and alcohol-abstaining subgroups. When split by alcohol status, the serum uric acid levels failed to show a significant difference in both gout (p = 0.92) and hyperuricemia (p = 0.23) subgroups. Overall, the results suggest that increased alcohol consumption does not play a causal role in the development of gout.

Joint Effect of Beer, Spirits Intake, and Excess Adiposity on Hyperuricemia Among Chinese Male Adults: Evidence From the China National Health Survey

Alcohol intake and excess adiposity are associated with serum uric acid (SUA), but their interaction effect on hyperuricemia (HUA) remains unclear. Using data from the China National Health Survey (CNHS) (2012-2017), we analyzed the additive interaction of beer, spirits intake, excess adiposity [measured by body mass index (BMI), body fat percentage (BFP), and visceral fat index (VFI)] with HUA among male participants aged 20-80 from mainland China. The relative excess risk due to interaction (RERI), the attributable proportion due to interaction (AP), and the synergy index (SI) were calculated to assess the interaction effect on the additive scale. Both RERI and AP larger than 0 and SI larger than 1 indicate a positive additive interaction. Among 12,592 male participants, the mean SUA level was 367.1 ± 85.5 μmol/L and 24.1% were HUA. Overweight/obese men who were presently drinking spirits had an odds ratio (OR) of 3.20 (95%CI: 2.71-3.79) than the never drink group, with RERI, AP, and SI of 0.45 (95%CI: 0.08-0.81), 0.14 (95%CI: 0.03-0.25), and 1.25 (95%CI: 1.02-1.54), respectively. However, although combined exposures on beer intake and excess adiposity had the highest OR compared with no beer intake and nonobese participants, there was no additive interaction, with RERI, AP, and SI in the overweight/obesity and the beer intake group of 0.58 (-0.41-1.57), 0.17 (-0.08-0.41), and 1.30 (0.85-1.97), respectively. Other excess adiposity indexes revealed similar estimates. Our findings suggested that the exposures of both excess adiposity and alcohol drink could result in an additive interaction effect on HUA: the combined risk of excess adiposity with spirits intake but not with beer was greater than the sum of the effects among Chinese male adults.