Gut microbiota plays a significant role in gout.

With the development of social economy, the incidence of gout is increasing, which is closely related to people's increasingly rich diet. Eating a diet high in purine, fat, sugar and low-fibre for a long time further aggravates gout by affecting uric acid metabolism. The renal metabolism mechanism of uric acid has been thoroughly studied. To find a new treatment method for gout, increasing studies have recently been conducted on the mechanism of intestinal excretion, metabolism and absorption of uric acid. The most important research is the relationship between intestinal microbiota and the risk of gout. Gut microbiota represent bacteria that reside in a host's gastrointestinal tract. The composition of the gut microbiota is associated with protection against pathogen colonization and disease occurrence. This review focuses on how gut microbiota affects gout through uric acid and discusses the types of bacteria that may be involved in the occurrence and progression of gout. We also describe potential therapy for gout by restoring gut microbiota homeostasis and reducing uric acid levels. We hold the perspective that changing intestinal microbiota may become a vital method for effectively preventing or treating gout.

Urate-lowering therapy, serum urate, inflammatory biomarkers, and renal function in patients with gout following pegloticase discontinuation.

BACKGROUND/PURPOSE: Little is known about long-term clinical outcomes or urate-lowering (ULT) therapy use following pegloticase discontinuation. We examined ULT use, serum urate (SU), inflammatory biomarkers, and renal function following pegloticase discontinuation. METHODS: We conducted a retrospective analysis of gout patients who discontinued pegloticase using the Rheumatology Informatics System for Effectiveness (RISE) registry from 1/2016 to 6/2022. We defined discontinuation as a gap ≥ 12 weeks after last infusion. We examined outcomes beginning two weeks after last dose and identified ULT therapy following pegloticase discontinuation. We evaluated changes in lab values (SU, eGFR, CRP and ESR), comparing on- treatment (≤ 15 days of the second pegloticase dose) to post-treatment. RESULTS: Of the 375 gout patients discontinuing pegloticase, median (IQR) laboratory changes following discontinuation were: SU: +2.4 mg/dL (0.0,6.3); eGFR: -1.9 mL/min (- 8.7,3.7); CRP: -0.8 mg/L (-12.8,0.0); and ESR: -4.0 mm/hr (-13.0,0.0). Therapy post-discontinuation included oral ULTs (86.0%), restarting pegloticase (4.5%), and no documentation of ULT (9.5%), excluding patients with multiple same-day prescriptions (n = 17). Oral ULTs following pegloticase were: 62.7% allopurinol, 34.1% febuxostat. The median (IQR) time to starting/restarting ULT was 92.0 days (55.0,173.0). Following ULT prescribing (≥ 30 days), only 51.0% of patients had SU < 6 mg/dL. Patients restarting pegloticase achieved a median SU of 0.9 mg/dL (IQR:0.2,9.7) and 58.3% had an SU < 6 mg/dL. CONCLUSION: Pegloticase treats uncontrolled gout in patients with failed response to xanthine oxidase inhibitors, but among patients who discontinue, optimal treatment is unclear. Based on this analysis, only half of those starting another ULT achieved target SU. Close follow-up is needed to optimize outcomes after pegloticase discontinuation.

Prednisolone Versus Colchicine for Acute Gout in Primary Care: statistical analysis plan for the pragmatic, multicenter, randomized, and double-blinded COPAGO non-inferiority trial.

BACKGROUND: To date, colchicine and prednisolone are two effective therapies for the treatment of acute gout but have never been compared directly in a randomized clinical trial. In addition, in previous trials of treating acute gout patients with concomitant comorbidities were often excluded due to contraindications to naproxen. STUDY DESIGN: This pragmatic, prospective, double-blind, double-dummy, parallel-group, randomized, non-inferiority trial compares prednisolone with colchicine in terms of non-inferiority in patients with acute gout. Patients presenting to their general practitioner with acute gout can be included if the gout attack has occurred within the last 2 days. A total of 60 practices in the vicinity of three university medical centers (Greifswald, Göttingen, and Würzburg) participate in the study. The intervention group receives 30 mg prednisolone for 5 days, while the group of standard care receives low-dose colchicine (day 1: 1.5 mg; days 2-5: 1 mg). The first dose of treatment is provided at day 0 when patients present to the general practitioner due to an acute gout attack. From day 0 to day 6, patients will be asked to complete a study diary on daily basis regarding pain quantification. For safety reasons, potential side effects and the course of systolic blood pressure are also assessed. STATISTICAL ANALYSIS PLAN: N = 314 patients have to be recruited to compensate for 10% of dropout and to allow for showing non-inferiority of prednisolone compared to colchicine with a power of 90%. We use permuted block randomization with block sizes of 2, 4, and 6 to avoid imbalanced treatment arms in this multi-center study; patients are randomized in a 1:1 ratio. The absolute level of pain on day 3 (in the last 24 h) is the primary outcome and measured on a numerical rating scale (NRS: 0-10). Using a multiple linear regression model adjusted for age, sex, and pain at baseline, prednisolone is considered non-inferior if the effect estimate including the confidence intervals is lower than a margin of 1 unit on the NRS. Average response to treatment, joint swelling and tenderness, physical function of the joint, and patients' global assessment of treatment success are secondary outcomes. DISCUSSION: The trial will provide evidence from a direct comparison of colchicine and prednisolone regarding their efficacy of pain reduction in acute gout patients of primary care and to indicate possible safety signals. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05698680 first posted on January 26, 2023 (retrospectively registered).

No causal association between pneumoconiosis and three inflammatory immune diseases: a Mendelian randomization study.

Objectives: To investigate the causal relationships between pneumoconiosis and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and gout. Methods: The random-effects inverse variance weighted (IVW) approach was utilized to explore the causal effects of the instrumental variables (IVs). Sensitivity analyses using the MR-Egger and weighted median (WM) methods were did to investigate horizontal pleiotropy. A leave-one-out analysis was used to avoid the bias resulting from single-nucleotide polymorphisms (SNPs). Results: There was no causal association between pneumoconiosis and SLE, RA or gout in the European population [OR = 1.01, 95% CI: 0.94-1.10, p = 0.74; OR = 1.00, 95% CI: 0.999-1.000, p = 0.50; OR = 1.00, 95% CI: 1.000-1.001, p = 0.55]. Causal relationships were also not found in pneumoconiosis due to asbestos and other mineral fibers and SLE, RA and gout [OR = 1.01, 95% CI: 0.96-1.07, p = 0.66; OR = 1.00, 95% CI: 1.00-1.00, p = 0.68; OR = 1.00, 95% CI: 1.00-1.00, p = 0.20]. Conclusion: Our study suggests that pneumoconiosis may have no causal relationship with the three inflammatory immune diseases.

The Causal Relationship between Angina Pectoris and Gout Based on Two Sample Mendelian Randomization.

Purpose: Two-sample Mendelian randomization (MR) was conducted to assess the causal relationship between angina pectoris and gout. Material and Methods. Based on genome-wide association studies, single nucleotide polymorphisms (SNPs) that were closely associated with gout were selected from the UK Biobank-Neale Lab (ukb-a-107) as genetic instrumental variables. Considering that gout is characterized by elevated blood uric acid levels, SNPs related to blood uric acid levels were screened from BioBank Japan (bbj-a-57) as auxiliary gene instrumental variables. SNPs closely associated with angina pectoris onset were screened from the FINN dataset (finn-b-I9_ANGINA) as outcome variables. Two-sample MR was conducted, with inverse variance weighting (IVW) of the random effects model as the primary result, along with the weighted median method (WME) and the MR-Egger regression method. To further confirm the causal relationship between angina and gout incidence, a meta-analysis was conducted on the IVW results of the ukb-a-107 and bbj-a-57. Results: The odds ratios and 95% confidence intervals of the IVW, WME, and MR-Egger results of ukb-a-107 were (OR = 33.72; 95% CI: 2.07∼550.38), (OR = 57.94; 95% CI: 2.75∼1219.82), and (OR = 96.38; 95% CI: 0.6∼15556.93), respectively. The P values of IVW and WME were 0.014 and 0.014 (both <0.05), respectively, indicating that the development of angina pectoris was significantly associated with the incidence of gout. The odds ratios and 95% confidence intervals of the IVW, WME, and MR-Egger about bbj-a-57 were (OR = 1.20; 95% CI: 1.07∼1.34), (OR = 1.19; 95% CI: 1.02∼1.38), and (OR = 1.30; 95% CI; 1.06∼1.60), respectively. The P values of IVW, WME and MR-Egger were 0.001, 0.027 and 0.017 (all <0.05), respectively, indicating a significant correlation between angina and blood uric acid levels. Scatter plots of ukb-a-107 and bbj-a-57 showed that the causal association estimates of the IVW, MR-Egger, and weighted median methods were similar and that the MR results were accurate. Funnel plots and the MR-Egger intercept of ukb-a-107 and bbj-a-57 showed the absence of horizontal pleiotropy. The leave-out sensitivity analysis results of ukb-a-107 and bbj-a-57 are stable. The meta-analysis of IVW results for ukb-a-107 and bbj-a-57 showed (OR = 1.20; 95% CI: 1.07-1.34, P=0.02), confirming that gout characterized by high blood uric acid levels significantly increases the risk of angina attacks. Conclusions: This MR study found a clear causal relationship between angina pectoris and gout, which increases the risk of angina pectoris.

The Impact of mHealth-Based Continuous Care on Disease Knowledge, Treatment Compliance, and Serum Uric Acid Levels in Chinese Patients With Gout: Randomized Controlled Trial.

Background: In patients with gout, suboptimal management refers to a lack of disease knowledge, low treatment compliance, and inadequate control of serum uric acid (SUA) levels. Several studies have shown that continuous care is recommended for disease management in patients with gout. However, in China, the continuous care model commonly used for patients with gout requires significant labor and time costs, and its efficiency and coverage remain low. Mobile health (mHealth) may be able to address these issues. Objective: This study aimed to explore the impact of mHealth-based continuous care on improving gout knowledge and treatment compliance and reducing SUA levels. Methods: This study was a single-center, single-blind, and parallel-group randomized controlled trial. Participants were recruited at the West China Hospital of Sichuan University in Chengdu, China, between February 2021 and July 2021 and were randomly assigned to the intervention and control groups. The intervention group received continuous care via an mHealth app, which includes modules for health records, 24 weeks of gout-related health education materials, and interactive support. The control group received routine continuous care, including face-to-face health education, paper-based health education materials consistent with the content for the intervention group, and telephone consultations initiated by the patient. Follow-up was conducted at 6 months. Participants' gout knowledge levels and treatment compliance were measured at baseline and the 12th and 24th weeks, and participants' SUA levels were measured at baseline and the 24th week. The intention-to-treat principle and a generalized estimating equation model were used to test the effect of the intervention. Results: Overall, 258 potential participants underwent eligibility assessments, and 120 were recruited and randomized into the intervention (n=60, 50%) and control (n=60, 50%) groups. Of the 120 participants, 93 (77.5%) completed the 24-week study. The 2 groups had no significant differences in sociodemographic or clinical characteristics, and the baseline measurements were comparable (all P>.05). Compared with the control group, the intervention group exhibited a significant improvement in gout knowledge levels over time (ß=0.617, 95% CI 0.104-1.129; P=.02 and ß=1.300, 95% CI 0.669-1.931; P<.001 at the 12th and 24th weeks, respectively). There was no significant difference in treatment adherence between the 2 groups at the 12th week (ß=1.667, 95% CI -3.283 to 6.617; P=.51), while a statistical difference was observed at the 24th week (ß=6.287, 95% CI 1.357-11.216; P=.01). At the 24th week, SUA levels in both the intervention and control groups were below baseline, but there was no significant difference in SUA changes between the 2 groups (P=.43). Conclusions: Continuous care based on the mHealth app improved knowledge levels and treatment compliance among patients with gout. We suggest incorporating this intervention modality into standard continuous care for patients with gout.

Assessment of the efficacy of alkaline water in conjunction with conventional medication for the treatment of chronic gouty arthritis: A randomized controlled study.

BACKGROUND: Chronic gouty arthritis, a prevalent metabolic disorder, has prompted interest in the role of diet and lifestyle in its management. This study examines alkaline water as a non-pharmacological adjunct to traditional medicine, hypothesizing its positive effects on uric acid levels and gout symptoms. METHODS: In this research, 400 chronic arthritis patients from Guangdong Hydropower Hospital (September 2021-September 2023) were randomly assigned to groups receiving varying concentrations of alkaline water alongside conventional Western medicine, or Western medicine alone. A 1-year follow-up involved assessments using visual analogue scales, joint swelling scores, functional assessment scales, and biochemical markers (serum uric acid, creatinine, urea nitrogen) for comprehensive evaluation. RESULTS: Pain relief: High-concentration alkaline water significantly reduced VAS pain scores posttreatment (P < .05). Joint swelling: Greatest improvement observed in high-concentration group (P < .001). Daily activity capability: Notable enhancements in daily activity scores in experimental groups (P < .05). Range of joint motion: All groups showed significant improvement posttreatment (P < .05). Inflammatory markers: Experimental groups experienced a notable decrease in C-reactive protein, especially in the low concentration group (P < .001). Erythrocyte sedimentation rate decreases were marginal and not statistically significant (P > .05). Interleukin-1ß and tumor necrosis factor-α levels significantly decreased, particularly in the low concentration group. Serum uric acid levels: Significant reduction in serum uric acid observed in all alkaline water groups (P < .05), contrasting with the control group. CONCLUSION: Alkaline water, particularly at high concentrations, effectively alleviated pain, reduced joint swelling, enhanced daily activities, and improved joint motion in chronic gouty arthritis treatment. It significantly reduced key inflammatory markers (C-reactive protein, interleukin-1ß, tumor necrosis factor-α) and serum uric acid levels, suggesting its potential as a valuable adjunct in gout management. The limited impact on erythrocyte sedimentation rate warrants further investigation.

Photosensitized covalent organic framework as a light-induced oxidase mimic for colorimetric detection of uric acid.

As large numbers of people are suffering from gout, an accurate, rapid, and sensitive method for the detection of gout biomarker, uric acid, is important for its effective control, diagnosis, and therapy. Although colorimetric detection methods based on uricase have been considered, they still have limitations as they produce toxic H2O2 and are expensive and not stable. Here, a novel uricase-free colorimetric method was developed for the sensitive and selective detection of uric acid based on the light-induced oxidase-mimicking activity of a new photosensitized covalent organic framework (COF) (2,4,6-trimethylpyridine-3,5-dicarbonitrile-4-[2-(4-formylphenyl)ethynyl]benzaldehyde COF [DCTP-EDA COF]). DCTP-EDA COF has a strong ability to harvest visible light, and it could catalyze the oxidation of 1,4-dioxane, 3,3',5,5'-tetramethylbenzidine under visible light irradiation to produce obvious color changes. With the addition of uric acid, however, the significant inhibition of the oxidase-mimicking activity of DCTP-EDA COF remarkably faded the color, and thus uric acid could be colorimetrically detected in the range of 2.0-150 µM with a limit of detection of 0.62 µM (3σ/K). Moreover, the present colorimetric method exhibited high selectivity; uric acid level in serum samples was successfully determined, and the recoveries ranged from 96.5% to 105.64%, suggesting the high accuracy of the present colorimetric method, which demonstrates great promise in clinical analysis.

Intensive urate-lowering with pegloticase plus methotrexate co-therapy in uncontrolled gout patients with and without chronic kidney disease: A retrospective case series.

Chronic kidney disease (CKD) and gout commonly co-occur. Pegloticase lowers serum urate (SU) in uncontrolled gout patients but antidrug antibodies limit urate-lowering response and increase infusion reaction (IR) risk. Methotrexate (MTX) co-administration increases pegloticase response rate and mitigates IR risk but CKD limits MTX use. This pooled case series examined pegloticase + MTX co-therapy in uncontrolled gout patients with and without CKD. Cases of pegloticase + MTX co-therapy in existing datasets were retrospectively examined. Baseline eGFR classified patients as CKD (eGFR < 60 mL/min/1.73 m2) or non-CKD (eGFR ≥ 60 mL/min/1.73 m2). Patient characteristics, treatment parameters, laboratory values, urate-lowering response rate (≥12 pegloticase infusions received and SU < 6 mg/dL just before infusion 12), and AEs were examined. Fifteen CKD (eGFR: 43.2 ±â€…11.3 mL/min/1.73 m2; SU: 8.6 ±â€…2.2 mg/dL), 27 non-CKD (eGFR: 82.9 ±â€…19.0 mL/min/1.73 m2; SU: 9.5 ±â€…1.7 mg/dL) patients were included. Comorbidity profiles were similar, but CKD patients were older (72.0 ±â€…9.9 vs 52.3 ±â€…14.3 years) and more often female (33.3% vs 7.4%). Treatment parameters were similar with 4-week MTX Run-in followed by mean of 14.7 ±â€…8.1 [CKD] vs 14.1 ±â€…7.1 [non-CKD] pegloticase infusions. However, CKD patients had lower MTX dose (14.8 ±â€…5.8 vs 19.3 ±â€…4.9 mg/week). Urate-lowering response was similar (92% vs 86%). eGFR increased during treatment in 60% of CKD (+11.5 ±â€…20.9 mL/min/1.73 m2, 87% stable/improved CKD-stage) and 44% of non-CKD (+4.2 ±â€…15.0 mL/min/1.73 m2) patients. AEs were similar (≥1 AE CKD: 53%, non-CKD: 67%; gout flare most-reported). One case each of pancytopenia and IR (mild) occurred in non-CKD patients. These real-world data show similar pegloticase + MTX efficacy in CKD and non-CKD patients. No new safety signals were identified, with most CKD patients showing renal function stability or improvement during therapy.

Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease: the ALL-HEART RCT and economic evaluation.

Background: Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol. Objective: To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease. Design: Prospective, randomised, open-label, blinded endpoint multicentre clinical trial. Setting: Four hundred and twenty-four UK primary care practices. Participants: Aged 60 years and over with ischaemic heart disease but no gout. Interventions: Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care. Main outcome measures: The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis. Results: From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective. Limitations: The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis. Conclusions: The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout. Future work: The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies. Trial registration: This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426). Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.

The purpose of the ALL-HEART study was to determine whether giving allopurinol to people with ischaemic heart disease (also commonly known as coronary heart disease) would reduce their risk of having a heart attack, stroke or of dying from cardiovascular disease. Allopurinol is a medication usually given to patients with gout to prevent acute gout flares. It is not currently used to treat ischaemic heart disease. We randomly allocated people aged over 60 years with ischaemic heart disease to take up to 600 mg of allopurinol daily (in addition to their usual care) or to continue with their usual care. We then monitored participants for several years and recorded any major health events such as heart attacks, strokes and deaths. We obtained most of the follow-up data from centrally held electronic hospital admissions and death records, making the study easier for participants and more cost-efficient. We asked participants in both groups to complete questionnaires to assess their quality of life during the study. We also collected data to determine whether there was any economic benefit to the NHS of using allopurinol in patients with ischaemic heart disease. There was no difference in the risk of heart attacks, strokes or death from cardiovascular disease between the participants given allopurinol and those in the group continuing their usual care. We also found no difference in the risks of other cardiovascular events, deaths from any cause or quality-of-life measurements between the allopurinol and usual care groups. The results of the ALL-HEART study suggest that we should not recommend that allopurinol be given to people with ischaemic heart disease to prevent further cardiovascular events or deaths.

Cardiovascular safety of febuxostat versus allopurinol among the Asian patients with or without gout: A systematic review and meta-analysis.

The cardiovascular (CV) safety of febuxostat compared to allopurinol for the treatment of hyperuricemia among Asian patients is uncertain. In this study, we conducted a systematic review and meta-analysis to compare the CV safety profiles of febuxostat with allopurinol in Asian patients with hyperuricemia. A total of 13 studies were included. On the basis of the pooled results of cohort studies, febuxostat users were at a significantly higher risk for acute coronary syndrome (ACS; hazard ratio [HR]: 1.06, 95% confidence interval [CI]: 1.03-1.09, p < 0.01), atrial fibrillation (HR: 1.19, 95% CI: 1.05-1.35, p < 0.01) than allopurinol users, whereas no significant difference between febuxostat and allopurinol existed for urgent coronary revascularization (HR: 1.07, 95% CI: 0.98-1.16, p = 0.13), and stroke (HR: 0.96, 95% CI: 0.91-1.01, p = 0.13). Nevertheless, that difference in results of acute decompensated heart failure (ADHF; HR: 0.73, 95% CI: 0.35-1.53, p = 0.40) and all-cause death (HR = 0.86, 95% CI: 0.49-1.51, p = 0.60) was not significant based on randomized controlled trials. In the Chinese subgroup, febuxostat could increase the risk of ADHF (HR: 1.22, 95% CI: 1.01-1.48, p < 0.05), CV death (HR: 1.25, 95% CI: 1.03-1.50, p < 0.05), and all-cause mortality (HR: 1.07, 95% CI: 1.01-1.14, p < 0.05) compared to allopurinol. In conclusion, the use of febuxostat, compared with allopurinol among Asian patients, was associated with a significantly increased risk of adverse CV events.

Coffee intake reduced gout risk by decreasing urate and urea while increasing SHBG levels in plasma: a mediation Mendelian randomization study.

OBJECTIVE: This study aims to investigate the causal relationships between specific dietary habits and the risk of gout, while identifying the mediators involved in these associations. METHODS: We initially assessed the causal effects of five dietary habits on gout by two-sample Mendelian randomization (MR). Subsequently, we identified mediators from five plasma metabolites by two-step MR, including urate, urea, sex hormone-binding globulin (SHBG), interleukin-18 (IL-18), and C-reactive protein (CRP). Next, we quantified the proportion of mediation effects by multivariable Mendelian randomization (MVMR). Last, we performed reverse MR analyses. Sensitivity analyses were conducted to enhance the robustness of our findings. RESULTS: Only coffee intake demonstrated a significant negative casual effect on gout (inverse variance weighted: OR = 0.444, p = 0.049). In two-step MR, coffee intake decreased urate and urea while increased SHBG levels, but did not affect IL-18 and CRP levels. Besides, urate and urea showed positive causal effects while SHBG exhibited a negative impact on gout. In mediation analysis, urate, urea, and SHBG respectively mediated 53.60%, 16.43%, and 4.81% of the total causal effect of coffee intake on gout. The three mediators collectively mediated 27.45% of the total effect. Reverse MR analyses suggested no significant reverse causal effects. Sensitivity analyses supported the reliability of our causal inferences. CONCLUSION: Coffee intake reduced gout risk by decreasing urate and urea while increasing SHBG levels in plasma. These findings accentuate the benefits of coffee intake for gout management. The mediators may provide a novel insight into potential therapeutic targets for gout prevention. Key Points • This study determines the causally protective effect of coffee intake on gout. • We reveal that coffee intake reduced the risk of gout by decreasing urate and urea while increasing SHBG levels in plasma. • Identifying specific mediators in the causal pathway from coffee intake to gout provides valuable information for clinical interventions of gout.

Comparison of the efficacy and safety of benzbromarone and febuxostat in gout and hyperuricemia: a systematic review and meta-analysis.

OBJECTIVE: Urate-lowering therapy (ULT) is widely recognized as the primary treatment for hyperuricemia and gout. Xanthine oxidase inhibitors (XOI), particularly febuxostat, have gained popularity as a frontline approach. However, the divergent efficacy and safety between febuxostat and the traditional ULT drug, benzbromarone, remain poorly understood. This knowledge gap necessitates a comprehensive analysis and evidence update to guide drug selection for physicians and patients. METHOD: We conducted a systematic analysis by extracting relevant clinical studies from four medical literature databases. Forest plots, funnel plots, sensitivity analysis, Egger's test, and subgroup analysis were utilized to compare relevant indicators. RESULTS: The advantages and disadvantages of the two drugs were evaluated based on various indicators such as serum uric acid (SUA), triglyceride (TG), urinary uric acid (UUA), white blood cell count (WBC), total cholesterol (TC), blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), estimated glomerular filtration rate (eGFR), and serum creatinine (SC). Benzbromarone demonstrated better efficacy in rapidly reducing SUA levels and inhibiting inflammation for hyperuricemia and gout patients. Febuxostat was slightly less effective in lowering SUA, but there was no significant difference in its impact on liver and kidney function after long-term use. CONCLUSION: This study highlights the superiority of benzbromarone in rapidly reducing SUA and inhibiting inflammation. Febuxostat shows comparable effects on liver and kidney function after long-term use. These findings provide valuable insights for clinicians and patients in drug selection. Key Points • Benzbromarone stands out as a highly effective treatment for hyperuricemia and gout, offering rapid reduction of serum uric acid levels and potent anti-inflammatory effects. • When it comes to long-term use, febuxostat demonstrates comparable effects on liver and kidney function. This provides reassurance for patients who require extended treatment duration. • Moreover, our study goes beyond previous research by presenting a more comprehensive and detailed analysis.

Prescribing cascades of antigout medications from thiazide diuretics in gout-naïve hypertensive adults receiving first-line pharmacological management.

Prescribing cascade is a significant clinical problem but is often overlooked. We explore the incidence of the prescribing cascades of antigout medications related to thiazide treatment in gout-naïve hypertensive adults newly exposed to the pharmacological treatment. This population-based, retrospective cohort study used the Taiwan National Health Insurance Registry Database. Gout-naïve hypertensive adults who were newly dispensed first-line antihypertensive drugs between January 1, 2000, and December 31, 2016, were enrolled. Patients were divided into the thiazide group (n = 4192) and the non-thiazide group (n = 81,083). The non-thiazide group included patients who received an angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, calcium channel blocker, or beta-blocker. The study utilized propensity score matching and multivariable Cox regression models to investigate the prescribing cascade of antigout agents following antihypertensive treatment, adjusting for factors like age, sex, comorbidities, and concurrent medications. After propensity score matching, each group consisted of 4045 patients, with the thiazide group exhibiting a higher risk of being prescribed antigout medications across different time intervals post-treatment initiation. Specifically, adjusted hazard ratios (aHRs) for the thiazide group were 2.23, 2.07, and 2.41 for < 30 days, 31-180 days, and > 180 days, respectively, indicating a sustained and significant risk over time. Comparative analyses revealed thiazide diuretics were associated with a higher risk of antigout medication prescriptions compared to other antihypertensive classes, particularly evident after 180 days. Subgroup analyses across various demographics and comorbidities consistently showed an increased risk in the thiazide cohort. Gout-naïve hypertensive adults newly dispensed thiazide had a higher risk of subsequently adding antigout agents than those taking other first-line antihypertensive medications. The awareness and interruption of these prescribing cascades are critical to improving patient safety.

Exploring the causal associations of micronutrients on urate levels and the risk of gout: A Mendelian randomization study.

BACKGROUND & AIMS: Growing evidence has indicated a potential association between micronutrient levels, urate levels, and the risk of gout. However, the causal association underlying these associations still remains uncertain. Previous observational studies and randomized controlled trials investigating the association between micronutrients, urate levels, and the risk of gout have been limited in their scope and depth. The aim of this study was to utilize Mendelian randomization (MR) to investigate the causal associations between genetically predicted micronutrient levels, urate levels, and the risk of gout. METHODS: In this study, we conducted a comprehensive examination of 10 specific micronutrients (vitamin B6, vitamin B12, vitamin C, vitamin D, folate, calcium, iron, copper, zinc, and selenium) as potential exposures. Two-sample MR analyses were performed to explore their causal associations with urate levels and the risk of gout. In these analyses, gout data were collected from the Global Biobank Meta-Analysis Initiative (N = 1,069,839, N cases = 30,549) and urate levels data from CKDGen Consortium (N = 288,649) by utilizing publicly available summary statistics from independent cohorts of European ancestry. We performed inverse-variance weighted MR analyses as main analyses, along with a range of sensitivity analyses, such as MR-Egger, weighted median, simple mode, weighted mode, Steiger filtering, MR-PRESSO, and Radial MR analysis, to ensure the robustness of our findings. RESULTS: The results of our study indicate that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout. Specifically, we found a negative association between vitamin B12 levels and urate levels, with a ß coefficient of -0.324 (95% CI -0.0581 to -0.0066, P = 0.0137) per one standard deviation (SD) increase. Similarly, a negative association was observed between folate levels and gout risk, with an odds ratio of 0.8044 (95% CI 0.6637 to 0.9750, P = 0.0265) per one SD increase. On the other hand, we identified positive associations between serum calcium levels and both urate levels and the risk of gout. Specifically, there was a positive association between serum calcium levels and urate levels (ß coefficient: 0.0994, 95% CI 0.0519 to 0.1468, P = 4.11E-05) per one SD increase. Furthermore, a positive association was found between serum calcium levels and the risk of gout, with an odds ratio of 1.1479 (95% CI 1.0460 to 1.2598, P = 0.0036) per one SD increase. These findings were robust in extensive sensitivity analyses. By employing MR-PRESSO and Radial MR to eliminate outliers, the observed associations have been reinforced. No clear associations were found between the other micronutrients and the urate levels, as well as the risk of gout. CONCLUSION: Our findings provided evidence that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout, while positive associations existed between the serum calcium levels and urate levels, as well as the risk of gout.

Middle Ear Tophi: A Case Series of Two Unusual Lesions and a Report of Facial Weakness and Review of the Literature.

OBJECTIVE: Tophaceous lesions of the middle ear from calcium pyrophosphate deposition disease (CPPD, or pseudogout) and gout are infrequently reported. Recognizing its characteristic findings will allow clinicians to accurately narrow the differential diagnosis of bony-appearing middle ear lesions and improve management. PATIENTS: Two consecutive cases of tophaceous middle ear lesions presenting to a tertiary care center between January 2021 and December 2021. Neither with previous rheumatologic history. INTERVENTIONS: Surgical excision of tophaceous middle ear lesions. MAIN OUTCOME MEASURE: Improvements in facial weakness and conductive hearing loss. RESULTS: The first case was a 66-year-old gentleman with progressive conductive loss, ipsilateral progressive facial weakness over years, and an opaque, irregular-appearing tympanic membrane anterior to the malleus found to have CPPD on surgical pathology, with immediate postoperative improvement of facial function. The second was a 75-year-old gentleman with progressive conductive loss and similar appearing tympanic membrane as case 1, previously diagnosed with tympanosclerosis, found to have gout on surgical pathology. In both cases, the CT showed a heterogenous, bony-appearing lesion in the middle ear, and both tophaceous lesions were a of gritty, chalky consistency intraoperatively. CONCLUSION: Tophaceous lesions of the middle ear are rare but have similar findings. Notably, the tympanic membrane can appear opaque and irregular, and the CT demonstrates a radiopaque, heterogeneous appearance. Facial weakness is an unusual finding. Specimens of suspected tophi must be sent to pathology without formalin for accurate diagnosis.

Efficacy and safety of orlistat in male patients with overweight/obesity and hyperuricemia: results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Obesity is associated with elevated serum uric acid (SUA) levels and frequent gout flares. Losing weight can reduce the SUA level and gout flares. The effect of orlistat on SUA levels and gout flares in patients with overweight/obesity and hyperuricemia (HUA) has not been extensively studied. This study investigated the effects of orlistat on SUA levels and gout flares compared to placebo in overweight and obese patients with HUA. METHODS: A total of 72 Chinese patients with overweight/obesity and HUA were randomly divided into a placebo group (35, 48.6%) and an orlistat group (37, 51.4%); the trial lasted 12 weeks. The primary endpoints were the relative changes in body weight, the SUA level, and gout flares in the per-protocol population. RESULTS: Orlistat reduced the proportion of patients with gout flares (log-rank P = 0.023, hazard ratio = 0.31, 95% confidence interval 0.11-0.85). There was no significant difference in SUA level between the two groups. The average weight loss of the orlistat group was 2.85 kg, and the average weight loss of the placebo group was 0.76 kg. The weight loss in the orlistat group was significantly greater than that in the control group (P < 0.05). CONCLUSIONS: This study is the first to demonstrate that orlistat has no significant effect on SUA levels in patients with overweight/obesity and HUA. The utility of orlistat as an adjunct therapy to prevent gout flares during weight loss in patients with HUA was emphasized. TRIAL REGISTRATION: Clinicaltrials.gov NCT05496075.