Epidemiology of gout: an update

Nanocubic cobalt-containing Prussian blue analogue-derived carbon-coated CoFe alloy nanoparticles for noninvasive uric acid sensing

This work describes an electrochemical sensor for the fast noninvasive detection of uric acid (UA) in saliva. The sensing material was based on a cobalt-containing Prussian blue analogue (Na2-xCo[Fe(CN)6]1-y, PCF). By optimizing the ratio of Co and Fe as 1.5 : 1 in PCF (PCF1.5,0), particles with a regular nanocubic morphology were formed. The calcination of PCF1.5,0 produced a carbon-coated CoFe alloy (CCF1.5), which possessed abundant defects and achieved an excellent electrochemical performance. Subsequently, CCF1.5 was modified on a screen-printed carbon electrode (SPCE) to fabricate the electrochemical sensor, CCF1.5/SPCE, which showed a sensitive and selective response toward salivary UA owing to its good conductivity, sufficient surface active sites and efficient catalytic activity. The determination of UA in artificial saliva achieved the wide linear range of 40 nM-30 μM and the low limit of detection (LOD) of 15.3 nM (3σ/s of 3). The performances of the sensor including its reproducibility, stability and selectivity were estimated to be satisfactory. The content of UA in human saliva was determined and the recovery was in the range of 98-107% and the total RSD was 4.14%. The results confirmed the reliability of CCF1.5/SPCE for application in noninvasive detection.

Gouty Arthritis Across Ages: Understanding Disease Patterns and Predictors

Introduction Gout, a chronic inflammatory joint disease, is increasingly prevalent worldwide, mainly affecting men, young females, and post-menopausal women. This study aims to investigate gout epidemiology in Al-Baha, Saudi Arabia, addressing the dearth of localized data on prevalence, risk factors, and management practices. Methods A cross-sectional analysis was conducted at King Fahad Hospital, Al-Baha, Saudi Arabia, covering 116 patients from March 2016 to November 2017. Data encompassed demographics, clinical presentations, and biochemical markers relevant to gout. Results Among 116 patients, 41 (35.3%) were diagnosed with gout, with males exhibiting a significantly higher prevalence than females (43.9% vs. 24%). Significant associations were found between gout prevalence and residency, occupational status, education level, clinical presentations (podagra, arthralgia/arthritis), and biochemical markers. Conclusion This study enriches global knowledge by providing localized insights into gout's epidemiology and highlighting demographic influences and clinical presentations specific to the Saudi context. The findings underscore the importance of tailored approaches in gout management, considering regional variations in prevalence, risk factors, and clinical manifestations.

Development and characterization of liposomal formulations containing sesquiterpene lactones for the treatment of chronic gout

Gout and hyperuricemia are characterized by high uric acid levels, and their treatment involves medications that have adverse effects. In this study, we evaluated oral liposomal formulations with eremantholide C and goyazensolide as a novel approach to reduce the toxicity associated with these substances while maintaining their anti-hyperuricemic activity. We characterized the formulations and evaluated them based on encapsulation efficiency and stability over 12 months and under simulated physiological environments. We determined the toxicity of the liposomal formulations in Caco-2 cells and the anti-hyperuricemic activity in rats. The formulations exhibited nanometric size, a narrow size distribution, and a negative zeta potential, indicating their stability and uniformity. The efficient encapsulation of the sesquiterpene lactones within the liposomes emphasizes their potential for sustained release and therapeutic efficacy. Stability evaluation revealed a small decrease in the eremantholide C concentration and a remarkable stability in the goyazensolide concentration. In Caco-2 cells, the liposomes did not exert toxicity, but did exhibit an antiproliferative effect. In vivo assays demonstrated that the liposomes reduced serum uric acid levels. Our study represents an advancement in gout and hyperuricemia treatment. The liposomal formulations effectively reduced the toxicity associated with the sesquiterpene lactones while maintaining their therapeutic effects.

Knowledge and attitudes of gout patients and their perspectives about diagnosis and management: A cross-sectional study in Saudi Arabia

BACKGROUND

Gout is a chronic noncommunicable disease that might lead to multiple systemic complications if it is left untreated. The knowledge, attitudes, and perceptives among patients toward the diagnosis and management of gout are important indicators in determining the prognosis and predicting sequelae of the disease. This cross-sectional survey aimed to assess the knowledge, attitudes, and perspectives of patients diagnosed with gout toward the disease diagnosis and treatment.

METHODOLOGY

An observational cross-sectional study was conducted at university clinics and local health facilities in central Riyadh, Saudi Arabia, for the duration between April and August 2022. Pearson χ2 test was used to determine the difference in the proportion of patients who adapt different attitudes and perspectives in terms of their demographic variables. Statistical significance was defined as a p value less than .05.

RESULTS

Two-hundred thirteen patients were involved in this study. The majority of the patients (84.0%) were diagnosed for more than 1 year. The majority of the patients (76.5%) were aged 25-60 years when they were diagnosed with gout. The most common complaint at the time of the diagnosis was joint pain (73.7%). The most commonly reported gout medication treatment being used was allopurinol accounting for 23.0%. The majority of the patients (83.6%) were satisfied regarding the effects of gout management on their job performance, work life, and careers. The vast majority (97.5%) reported that they are satisfied with the health service provided.

CONCLUSION

The patients diagnosed with gout in Saudi Arabia exhibited a satisfactory level of information, attitude, and perspectives regarding their condition. The participants expressed a significant degree of satisfaction with the impact of gout management on their occupational performance, work-life balance, and professional plans. Additional research is necessary to ascertain the risk factors associated with gout and provide suitable preventative interventions.

Living with gout. Experiences, impact and challenges of the disease. Qualitative study through focus groups

OBJECTIVE

To delve into the experiences of people living with gout regarding its causes and triggers, recommended treatments and therapeutic measures, and the impact of living with this problem.

SUBJECTS AND METHODS

Descriptive qualitative study. Opinion sampling, looking for discursive variability according to sex, age, socioeconomic position and treatments. Three focus groups were made with 11, 6 and 7 people, following a pre-established script of topics. Analysis following thematic content analysis procedures.

RESULTS

Participants were 19 men and 5 women, of different ages, socioeconomic status and treatments. Frequent comorbidities: hypertension and hypercholesterolemia. Genetics and the lack of renal elimination of urate were mentioned as causes of gout. They reported little knowledge of the causes and need more explanations about them. As triggers of the attack they identified: excess food and/or alcohol, trauma, stress or not following the treatment. Various drug treatment and expressed concern about their possible adverse effects were listed. Difficulties in adherence to the recommendations were also described. Non-pharmacological measures: rest, cold, proper footwear, walking, drinking water, and diet were also described. Chronic gout has an important impact on the daily life of patients and their families. Pain invalidates and leads to difficulties in performing daily activities. Irritations and mood swings were reported, which affect their family relationships.

CONCLUSIONS

These findings provide proposals to improve the care of people with gout. Information on its causes, the triggers of the crisis, dietary recommendations and exercise should be improved. The variability of treatments and recommendations on lifestyle should be analysed in depth.

Differences in the Association Between Alcoholic Beverage Type and Serum Urate Levels Using Standardized Ethanol Content

IMPORTANCE

Differences have been observed in the association of serum urate levels with consumption of different types of alcoholic beverages. However, previous studies have not standardized the unit of intake for ethanol content, and only limited types of alcoholic beverages have been evaluated.

OBJECTIVE

To examine differences in the association of serum urate levels with various types of alcoholic beverages when their intakes are standardized for ethanol content.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cross-sectional study was conducted using data from participants aged 20 years or older who completed a medical checkup at St Luke's International University in Japan between October 1, 2012, and October 31, 2021. Participant demographics, blood test results, and lifestyle questionnaire data were used as covariates. Analysis was performed in December 2021.

EXPOSURES

Consumption of alcoholic beverages, including beer, sake (rice wine), shochu (Japanese spirit), wine, and whiskey.

MAIN OUTCOMES AND MEASURES

Serum urate levels were measured during the medical checkup. The beverage unit was standardized to 1 standard drink, which contained 20 g of ethanol. Multivariable linear regression including interaction terms of alcohol consumption and dominant alcoholic beverage was performed.

RESULTS

This study included 78 153 participants. Their mean (SD) age was 47.6 (12.8) years; 36 463 (46.7%) were men and 41 690 were women (53.3%). A total of 45 755 participants (58.5%) were regular alcohol drinkers. Consistent associations of serum urate levels with alcohol consumption were observed in the beer-dominant group, with β coefficients (for 1 standard drink per day) of 0.14 mg/dL (95% CI, 0.11-0.17 mg/dL; P < .001) for men and 0.23 mg/dL (95% CI, 0.20-0.26 mg/dL; P < .001) for women. A moderate increase in serum urate levels was observed in the wine-dominant group compared with a modest and nonsignificant increase in the sake-dominant group, with β coefficients (for 1 standard drink per day) for the latter group of 0.05 mg/dL (95% CI, -0.01 to 0.10; P = .10) for men and 0.04 mg/dL (95% CI, -0.05 to 0.14 mg/dL; P = .38) for women. Restricted cubic splines showed different patterns in associations of serum urate levels with ethanol intake by dominant alcoholic beverages.

CONCLUSIONS AND RELEVANCE

The results of this study suggest that the extent of the association of serum urate levels with alcohol intake was different for alcoholic beverages even after ethanol content was standardized. Higher beer consumption among men and women was consistently associated with higher serum urate levels, whereas sake was not associated with changes in serum urate levels. Therefore, alcoholic beverage type, in addition to ethanol content, should be considered as a factor contributing to hyperuricemia.

The Burden of Gout and Its Attributable Risk Factors in the Middle East and North Africa Region, 1990 to 2019

OBJECTIVE

This study reported the burden of gout and its attributable risk factors in the Middle East and North Africa (MENA) region between 1990 and 2019 by age, sex, and sociodemographic index (SDI).

METHODS

Data on the prevalence, incidence, and years lived with disability (YLD) due to gout were obtained from the Global Burden of Disease 2019 study for the 21 countries in the MENA region, from 1990 to 2019.

RESULTS

In 2019, the regional age-standardized point prevalence and annual incidence rates of gout were 509.1 and 97.7 per 100,000 population, which represent a 12% and 11.1% increase since 1990, respectively. Moreover, in 2019 the regional age-standardized YLD rate was 15.8 per 100,000 population, an 11.7% increase since 1990. In 2019, Qatar and Afghanistan had the highest and lowest age-standardized YLD rates, respectively. Regionally, the age-standardized point prevalence of gout increased with age up to the oldest age group, and it was more prevalent among males in all age groups. In addition, there was an overall positive association between SDI and the burden of gout between 1990 and 2019. In 2019, high BMI (46.1%) was the largest contributor to the burden of gout in the MENA region.

CONCLUSION

There were large intercountry variations in the burden of gout, but in general, it has increased in MENA over the last 3 decades. This increase is in line with the global trends of gout. However, the age-standardized YLD rate change was higher in MENA than at the global level.

Application of state-target application of painful arthritis liver and kidney deficiency: A review

In recent years, with the progress and development of the times, our eating habits and lifestyle changes have led to an increase in gouty arthritis annually, with the main use of nonsteroidal anti-inflammatory drugs and other drugs. These drugs are highly dependent, resulting in an unresponsive state, which is easy to recur. Therefore, more and more patients choose traditional Chinese medicine (TCM) to treat them. After years of continuous exploration and rich clinical experience accumulation, Academician TongXiaolin put forward the dialectical strategy of "combination of state and target" in TCM. He believed that the deficiency of liver and kidney is transformed into a state, with uric acid as the target. Through the target prescription Simiao decoction to clever heat and moisture, replenishing liver and kidney, the target medicine Bixie (Dioscorea Tokoro Makino) to rheumatism, Shujin;Tufuling (Rhizoma Smilacis Glabrae) for detoxification, dehydration gas, Weilingxian (Radix et Rhizoma Clematidis) to rheumatism, pass meridians, and the combination of the condition and target achieves a good clinical effect.

Considerations for Choosing First-Line Urate-Lowering Treatment in Older Patients with Comorbid Conditions

Gout is the most common inflammatory arthritis in adults. The prevalence of gout increases with age. Urate-lowering treatment (ULT) among older patients is often challenging in that patients frequently suffer insufficient effectiveness or adverse events due to comorbidities, concurrent medications, and altered pharmacokinetics. The large-scale randomized controlled trials (RCTs) directly investigating gout patients regarding cardiovascular (CV) safety have only recently been introduced; CARES and FAST compared the CV safety of the two xanthine oxidase inhibitors (XOis), febuxostat versus allopurinol, in patients with gout. Based on the CARES trial that showed CV concerns with febuxostat, the current international guidelines recommend allopurinol as first-line ULT in gout, while preserving other agents as a second-line treatment, despite a higher potency of febuxostat. XOis would be more suitable than uricosurics to treat older patients with gout due to the high prevalence of chronic kidney disease (CKD) in older patients. However, allopurinol alone might not achieve the target serum uric acid levels below 6 mg/dL and CKD might confer an increased risk of allopurinol induced cutaneous adverse reactions in older patients. Furthermore, as well as the later analysis of CARES participants who were lost to follow-up, data from the FAST trial and real-world studies suggest non-inferior CV safety for febuxostat compared to allopurinol even in the presence of CV diseases. Thus, febuxostat use in older patients with renal impairment may be more positively considered. The combination therapy of a novel uricosuric, verinurad, plus febuxostat reduced albuminuria in hyperuricemic patients with type 2 diabetes and CKD in a phase 2a trial, and further RCTs are awaited. Finally, the sodium-glucose cotransporter-2 inhibitor class of oral hypoglycemic agents, known to exert beneficial CV and renal effects independent of glycemic control, have shown a uricosuric effect and could be used as adjunctive therapy in older patients with cardiorenal comorbidities.

Highly sensitive visual colorimetric sensor for xanthine oxidase detection by using MnO2-nanosheet-modified gold nanoparticles

In this study, a highly sensitive colorimetric assay has been constructed for the determination of xanthine oxidase (XOD) activity by the GNP@MnO₂ core-shell nanoparticles as probe. In the presence of XOD, xanthine can be oxidized to produce H₂O₂, which makes the MnO₂ shell fallen off. With the single particle detection (SPD) based dark field microscopy (DFM), the scattering color of GNP@MnO₂ NP probe shows obvious change before and after etching process. At the single particle level, noticeable color change of the single probe can be easily detected in the existence of trace XOD. This SPD-based colorimetric strategy displays broad linear dynamic range (0.02-4 mU/mL) and low detection limit of 7.82 μU/mL, which is more sensitive than the results from ensemble sample measurement. In addition, we tested the inhibitory effect of quercetin on the activity of XOD and obtained good inhibition effect. As a consequence, this SPD-based colorimetric strategy provides new perception for the ultrasensitive detection of molecules in complex system.

Imaging of Crystal Disorders:: Calcium Pyrophosphate Dihydrate Crystal Deposition Disease, Calcium Hydroxyapatite Crystal Deposition Disease and Gout Pathophysiology, Imaging, and Diagnosis

Crystal arthropathies are a group of joint disorders due to deposition of crystals in and around joints that lead to joint destruction and soft tissue masses. Clinical presentation is variable and diagnosis might be challenging. In this article the pathophysiology is addressed, the preferred deposition of crystal arthropathies and imaging findings. Case studies of calcium pyrophosphate dihydrate crystal deposition disease, hydroxyapatite crystal deposition disease, and gout are shown. Guidelines for the use of dual-energy computed tomography are given to enable the diagnosis and follow-up of gout.

Review on recent advances in fabrication of enzymatic and chemical sensors for hypoxanthine

Hypoxanthine is an important product of the nucleotide degradation pathway. It has been considered as a potential marker for assessing meat freshness and clinical diagnosis. In the review, we focus on advancement made in the fabrication of hypoxanthine sensors. Several traditional methods are being utilized for the detection of hypoxanthine, but these methods are expensive, complex, require pretreatment of the sample which is time-consuming and trained persons to operate. Sensors have emerged as simple, rapid, economic, disposable, and portable tools for hypoxanthine detection in biological samples. In particular, the review describes the significant role of hypoxanthine in clinical and food applications. Classification of sensors into enzymatic and non-enzymatic sensors along with the different methods used for xanthine oxidase immobilization and type of transducers used for hypoxanthine detection are briefly explained.

Dietary supplements for chronic gout

BACKGROUND

Dietary supplements are frequently used for the treatment of several medical conditions, both prescribed by physicians or self administered. However, evidence of benefit and safety of these supplements is usually limited or absent.

OBJECTIVES

To assess the efficacy and safety of dietary supplementation for people with chronic gout.

SEARCH METHODS

We updated the original search by searching CENTRAL, MEDLINE, Embase, CINAHL, and four trials registers (August 2020). We applied no date or language restrictions. We also handsearched the abstracts from the 2010 to 2019 American College of Rheumatology and European League against Rheumatism conferences, and checked the references of all included studies.

SELECTION CRITERIA

We considered all published randomised controlled trials (RCTs) or quasi-RCTs that compared dietary supplements with no supplements, placebo, another supplement, or pharmacological agents for adults with chronic gout for inclusion. Dietary supplements included, but were not limited to, amino acids, antioxidants, essential minerals, polyunsaturated fatty acids, prebiotic agents, probiotic agents, and vitamins. The major outcomes were acute gout flares, study withdrawal due to adverse events (AEs), serum uric acid (sUA) reduction, joint pain reduction, participant global assessment, total number of AEs, and tophus regression.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Two previously included RCTs (160 participants) met our inclusion criteria; we did not identify any new trials for this update. As these two trials evaluated different diet supplements (enriched skim milk powder (SMP) and vitamin C) with different outcomes (gout flare prevention for enriched SMP, and sUA reduction for vitamin C), we reported the results separately. One trial (120 participants), at unclear risk of selection and detection bias, compared SMP enriched with glycomacropeptides (GMP) with un-enriched SMP, and with lactose, over three months. Participants were predominantly men, aged in their 50s, who had severe gout. The results for all major outcomes were imprecise, except for pain. None of the results were clinically significant. The frequency of acute gout attacks, measured as the number of flares per month, decreased in all three groups over the three-month study period. The effects of enriched SMP (SMP/GMP/G600) compared with the combined control groups (SMP and lactose powder) at three months in terms of mean number of gout flares per month were not clinically significant (mean (standard deviation (SD)) flares per month: 0.49 (1.52) in SMP/GMP/G60 group versus 0.70 (1.28) in the control groups; absolute risk difference: mean difference (MD) -0.21 flares per month, 95% confidence interval (CI) -0.76 to 0.34; low-quality evidence). The number of withdrawals due to adverse effects was similar between groups (7/40 in SMP/GMP/G600 group versus 11/80 in control groups; (risk ratio (RR) 1.27, 95% CI 0.53 to 3.03); there were 4% more withdrawals in the SMP/lactose groups (10% fewer to 18% more; low-quality evidence). Serum uric acid reduction was similar across groups (mean (SD) -0.025 (0.067) mmol/L in SMP/GMP/G60 group versus -0.010 (0.069) in control groups; MD -0.01, 95% CI -0.04 to 0.01; low-quality evidence). Pain from self-reported gout flares (measured on a 10-point Likert scale) improved slightly more in the GMP/G600 SMP group compared with controls (mean (SD) -1.97 (2.28) in SMP/GMP/G600 group versus -0.94 (2.25) in control groups; MD -1.03, 95% CI -1.89 to -0.17). This was an absolute reduction of 10% (95% CI 20% to 1% reduction; low-quality evidence), which may not be of clinical relevance. The risk of adverse events was similar between groups (19/40 in SMP/GMP/G600 group versus 39/80 in control groups; RR 0.97, 95% CI 0.66 to 1.45); the absolute risk difference was 1% fewer adverse events (1% fewer to 2% more), low-quality evidence). Gastrointestinal events such as nausea, flatulence and diarrhoea were the most commonly reported adverse effects. Data for participant global assessment were not available for analysis; the study did not report tophus regression. One trial (40 participants), at high risk of selection, performance, and detection bias, compared vitamin C alone with allopurinol, and with allopurinol plus vitamin C, in a three-arm study. We only included data from the vitamin C versus allopurinol comparison in this review. Participants were predominantly middle-aged men, and their severity of gout was representative of gout in general. Allopurinol reduced sUA levels more than vitamin C (MD 0.10 mmol/L, 95% CI 0.06 to 0.15), low-quality evidence. The study reported no adverse events; none of the participants withdrew due to adverse events. The study did not assess the rate of gout attacks, joint pain reduction, participant global assessment, or tophus regression.

AUTHORS' CONCLUSIONS

While dietary supplements may be widely used for gout, this review found no high-quality that supported or refuted the use of glycomacropeptide-enriched skim milk powder or vitamin C for adults with chronic gout.

Metabolites of Procyanidins From Litchi Chinensis Pericarp With Xanthine Oxidase Inhibitory Effect and Antioxidant Activity

Procyanidins from litchi pericarp (LPPC) has been evidenced to possess strong antioxidant activities in vivo that is possibly correlated with their intestinal metabolites. However, the xanthine oxidase inhibitory effect of LPPC and its metabolites was less concerned. In this study, three oligomeric procyanidins and eight metabolic phenolic acids were identified in the urine of rats administrated with LPPC by high performance liquid chromatography and liquid chromatography-mass spectrometry analysis. Data indicated that all the metabolites excreted were significantly increased by the treatment of 300 mg/kg body weight of LPPC (P < 0.05), revealing considerable 1, 1-Diphenyl-2-Picrylhydrazyl (DPPH) and hydroxyl radicals activities of scavenging. Moreover, phenolic metabolites involving epicatechin, A-type dimer, A-type trimer, caffeic acid, and shikimic acid exhibited greater xanthine oxidase inhibition effects compared with other metabolites, with an inhibitory rate higher than 50% at the concentration 200 μg/ml. The IC₅₀ value of these five phenols were 58.43 ± 1.86, 68.37 ± 3.50, 74.87 ± 1.30, 95.67 ± 3.82, and 96.17 ± 1.64 μg/ml, respectively. As a whole, this work suggests that the xanthine oxidase inhibition and antioxidant activity of LPPC-derived metabolites as one of the mechanisms involved in the beneficial effects of LPPC against hyperuricemia or gout.

Uric acid extrarenal excretion: the gut microbiome as an evident yet understated factor in gout development

Humans do not produce uricase, an enzyme responsible for degrading uric acid. However, some bacteria residing in the gut can degrade one-third of the dietary and endogenous uric acid generated daily. New insights based on metagenomic and metabolomic approaches provide a new interest in exploring the involvement of gut microbiota in gout. Nevertheless, the exact mechanisms underlying this association are complex and have not been widely discussed. In this study, we aimed to review the evidence that suggests uric acid extrarenal excretion and gut microbiome are potential risk factors for developing gout. A literature search was performed in PubMed, Web of Science, and Google Scholar using several keywords, including "gut microbiome AND gout". A remarkable intestinal dysbiosis and shifts in abundance of certain bacterial taxa in gout patients have been consistently reported among different studies. Under this condition, bacteria might have developed adaptive mechanisms for de novo biosynthesis and salvage of purines, and thus, a concomitant alteration in uric acid metabolism. Moreover, gut microbiota can produce substrates that might cross the portal vein so the liver can generate de novo purinogenic amino acids, as well as uric acid. Therefore, the extrarenal excretion of uric acid needs to be considered as a factor in gout development. Nevertheless, further studies are needed to fully understand the role of gut microbiome in uric acid production and its extrarenal excretion, and to point out possible bacteria or bacterial enzymes that could be used as probiotic coadjutant treatment in gout patients.

No Effect of Added Sugars in Soft Drink Compared With Sugars in Fruit on Cardiometabolic Risk Factors: Results From a 4-Week, Randomized Controlled Trial

High intakes of added sugar from soft drinks are associated with negative health outcomes such as the increased risk of gout and type 2 diabetes, weight gain and cardiovascular disease. Fruits are naturally high in sugars but their effect on cardiometabolic risk remains unknown. We examined the effect on cardiometabolic risk factors of consuming natural sugars from fruit or added sugars from sugar-sweetened soft drinks in overweight adults. Forty-eight healthy, overweight (BMI ≥ 28 kg/m²) men (n = 21) and women (n = 20) were randomized to either a fruit (n = 19) or sugar-sweetened soft drink (n = 22) intervention for 4 weeks. The fruit group received 6 items of fresh and dried fruit per day and the sugar-sweetened soft drink group received 955 ml of sugar-sweetened soft drink per day. The interventions were matched for both energy (fruit: 1,800 kJ/d; soft drink: 1,767 kJ/d) and fructose content (fruit: 51.8 g/d; soft drink: 51.7 g/d). The soft drink intervention provided 101 g total sugars, which was all added sugar and the fruit intervention provided 97 g total sugars, which were all natural sugars. Dietary intakes were otherwise ad libitum. Despite being asked to consume additional sugar (up to 1,800 additional kJ/d), there were no changes in weight, blood pressure or other cardiometabolic risk factors, except by uric acid, in any of the intervention groups. In conclusion, our findings do not provide any evidence that short-term regular intake of added sugars is linked to higher cardiometabolic risks, with exception of uric acid in overweight men. Public health interventions to prevent obesity and related diseases should focus on the quality of the whole diet rather than only focusing on reducing sugary drinks or sugar intakes.

The inflammatory role of silent urate crystal deposition in intercritical gout

OBJECTIVE

To study subclinical inflammation in intercritical gout patients and its relation to the estimated size of monosodium urate crystal deposition and cardiovascular risk factors.

METHODS

We performed a secretome analysis and the quantification of cytokine and adipokine plasma levels (IL-1β, IL-18, IL-6, sIL-6R, TNFα, CXCL5, RANTES, leptin, resistin and adiponectin) to analize subclinical inflammation in intercritical gout patients. Since it is currently not feasible to determinate the whole body deposit of monosodium urate crystals, we created an indirect clinical classification to estimate it. Then, we compared cytokine levels in controls and gout patients, and in patients with different crystal deposition size. We also studied the association between cytokine-levels and the number of cardiovascular risk factors.

RESULTS

Ninety consecutive patients attending a Crystal Arthritis Unit were studied. IL-18, sIL-6R, RANTES, leptin and adiponectin were higher in intercritical gout patients than in controls. An association was observed between IL-18, sIL6-R and RANTES levels and the size of crystal deposition. IL-18, sIL6-R, RANTES and leptin were higher in patients with no cardiovascular risk factors when compared with controls with no risk factors.

CONCLUSION

Our results showed that the levels of some proinflammatory cytokines and metabolic proteins are elevated in intercritical gout patients. The levels of certain cytokines was related to the estimated size of the monosodium urate crystal deposition and to the number of cardiovascular risk factors. These cytokine changes may help to explain the increase of the cardiovascular events in gout patients.

Incident gout and weight change patterns: a retrospective cohort study of US adults

BACKGROUND

Although the relationship between obesity and incident gout has been clarified, the influence of weight changes during the transition from early adulthood to midlife and the different weight change patterns in specific age ranges on the incidence of gout in later life remain unknown. Therefore, we aimed to investigate the association between weight change patterns across adulthood and incident gout.

METHODS

Using data from the National Health and Nutrition Examination Survey (NHANES), we categorized individuals into four weight change patterns: those who remained obese (stable obese), those who moved from a non-obese body mass index (BMI) to an obese BMI (gaining), those who moved from an obese BMI to a non-obese BMI (losing), and those who remained non-obese (stable non-obese). Incident gout reflected its occurrence over the 10-year follow-up from the recalled midlife weight measure to the time of this survey. Hazard ratios (HRs) and 95% confidence intervals relating weight change patterns to incident gout over the 10-year follow-up period were calculated using Cox models adjusted for covariates. The hypothetical population attributable fraction (PAF) for the weight change patterns was calculated.

RESULTS

Among our sample of adults aged 40-74 years at their midlife weight measure (n = 11,079), 320 developed gout. The highest risk of incident gout was found for participants with the stable obese pattern (HR 1.84; 1.08-3.14) and not for participants who remained stable non-obese during adulthood. Moreover, gaining weight was a significant risk factor for incident gout (HR 1.65; 1.19-2.29). No significant associations were found between losing weight change patterns and the risk of gout during the study period. If participants who gained weight had become non-obese during the 10-year follow-up, an estimated 3.2% (95% CI 0-6.3) of observed gout cases could have been averted. In addition, if the population had maintained a normal BMI, 32.9% (95% CI 18.2-44.9) cases could have been prevented during the 10 years.

CONCLUSIONS

Gaining weight over adulthood was associated with an increased risk of gout. These findings have highlighted that maintaining non-obese weight and weight loss across adulthood is essential for the prevention and treatment of gout in adult life.

Developing, optimizing, and assessing a green electrophoretic method for determination of benzbromarone and allopurinol with its active metabolite in biological and pharmaceutical matrices

A combination of allopurinol and benzbromarone is a common gout treatment protocol. A suboptimal response to allopurinol in patients is very common due to its pharmacokinetics variability. Moreover, the safe doses of benzbromarone is very crucial in patients with hepatic diseases. This raised the inquisitiveness to develop and optimize a capillary zone electrophoresis method for the determination of allopurinol and benzbromarone in their coformulation and in the presence of oxypurinol, the active metabolite of allopurinol, in biological and pharmaceutical matrices. The method greenness profile was assessed using green metric tools the "National Environmental Method Index," the "Analytical Eco-Scale," and the "Green Analytical Procedure Index" by which the method proved to be ecofriendly. The method was successfully applied for the analysis of the pharmaceutical preparation and urine samples spiked with both drugs and the active metabolite. The linearity range was 25.0-250.0 μg/mL for benzbromarone, 50.0-350.0 μg/mL for allopurinol, and 100.0-500.0 μg/mL for oxypurinol. The recoveries were 99.60 ± 0.67, 99.89 ± 0.98, and 98.71 ± 1.18% for benzbromarone, allopurinol, and oxypurinol, respectively. The analysis results indicate potential usefulness of capillary zone electrophoresis as a competitive and greener method of analysis in biological and quality control labs.

Ultrasonography and dual-energy computed tomography: impact for the detection of gouty deposits

Ultrasonography (US) and dual-energy computed tomography (DECT) are useful and sensitive diagnostic tools to identify monosodium urate deposits in joints and soft tissues. The purpose of this review is to overview the imaging findings obtained by US and DECT in patients with gout, to understand the strengths and weaknesses of each imaging modality, and to evaluate the added value of using both modalities in combination.

Cost-effectiveness of allopurinol versus febuxostat in the treatment of gout patients: A systematic review

Background: In recent years, increased longevity, poor dietary habits, and the rising prevalence of metabolic syndrome and hypertension have increased the prevalence of gout. Gout significantly increases direct and indirect costs and reduces the quality of life. Allopurinol and febuxostat are the most commonly used drugs for reducing uric acid levels and controlling this disease with different cost-effectiveness. The present systematic review compares the cost-effectiveness of these drugs. Methods: This was a systematic review of economic evaluations. Cochrane CENTRAL, Web of Science, PubMed, Embase, and the Cost-Effectiveness Analysis (CEA) Registry were searched up to April 30, 2018, based on the specific search strategy of each database. Keywords used in the search include gout, cost-effectiveness, allopurinol, and febuxostat in MeSH and free-text forms. Screening of identified studies, data extraction, and quality assessment were done independently by 2 reviewers. The quality of studies was assessed based on Drummond Checklist. Finally, a qualitative analysis was done to analyze the results. Results: A total of 94 studies were identified through database search and the review of references. After screening the titles, abstracts, and full-texts, 6 economic evaluations were included in the review. The majority of the studies had been conducted in the US using the Markov model, within a 5-year horizon, and from the payer's perspective, with the quality of life as a measure of effectiveness. In most studies, the incremental cost-effectiveness ratios (ICERs) of febuxostat per quality-adjusted life year (QALY) were below the threshold (10 000$/QALY and 30 000€/QALY). Conclusion: Febuxostat has been shown to be more cost-effective than allopurinol in all treatment sequences in studies that have used uric acid levels as the measure of effectiveness. Furthermore, in studies with the quality of life as the measure of effectiveness, febuxostat has been shown to be very cost-effective as the second-line treatment.

The impact of gout as described by patients, using the lens of The International Classification of Functioning, Disability and Health (ICF): a qualitative study

Background

The International Classification of Functioning, Disability and Health (ICF) aims to comprehensively describe the ways in which a person’s health condition affects their life. This study aimed to contribute to the development of an ICF core set for gout through patient opinion derived from focus groups and interviews.

Methods

We conducted a secondary qualitative analysis of data from three studies investigating the patient experience of gout. In total there were 30 individual interviews and 2 focus groups (N = 17) comprising 47 participants. We conducted thematic analysis of the textual data to extract meaning units, which were then linked to the ICF.

Results

A large number of ICF categories were relevant to patients with gout. Participants mentioned 93 third level categories, 17 of which were mentioned by more than 50% of patients. The most references for a single category was for b280, Sensation of pain, followed by personal factors (not yet categorised by the ICF). The most participants mentioned the environmental factor e355, Health professional support, followed by b280, Sensation of pain.

Conclusion

The categories identified in this study as relevant to patients with gout highlight the severe pain associated with this disease, the impact on mobility and corresponding life areas. The roles of health professional support, medication, and personal attitudes to disease management are also reflected in the data. These results will contribute to the development of the ICF core set for gout.

Allopurinol-Induced Oral Lichenoid Drug Reaction with Complete Regression after Drug Withdrawal

Background: Lichen planus is a chronic mucocutaneous inflammatory disease. Oral manifestations are common, and may remain exclusive to the oral mucosa without involvement of the skin or other mucosae. A differential diagnosis includes oral lichenoid drug reactions. Allopurinol, which is the first line hypo-uricemic treatment, is often quoted as being a possible offending drug, though oral reactions have rarely been reported. Case presentation: We describe a 59-year-old male gout patient, successfully treated with allopurinol, who developed acute onset of oral lichenoid lesions, involving bilaterally the buccal mucosa, the tongue and the labial mucosa. Histopathology was consistent with a lichen planus or a drug-induced lichenoid reaction. Improvement of the patient's condition after withdrawal of allopurinol confirmed the lichenoid nature of the lesion. Remission was complete after a few weeks. Discussion: Although unusual, allopurinol may induce a lichenoid drug reaction. These reactions may mimic clinically and histopathologically idiopathic lichen planus. Improvement or complete regression of the lesions may be attempted to confirm the diagnosis. According to the latest WHO recommendations, these lesions have a potential for malignant transformation.

Allopurinol-Induced Oral Lichenoid Drug Reaction with Complete Regression after Drug Withdrawal

Background: Lichen planus is a chronic mucocutaneous inflammatory disease. Oral manifestations are common, and may remain exclusive to the oral mucosa without involvement of the skin or other mucosae. A differential diagnosis includes oral lichenoid drug reactions. Allopurinol, which is the first line hypo-uricemic treatment, is often quoted as being a possible offending drug, though oral reactions have rarely been reported. Case presentation: We describe a 59-year-old male gout patient, successfully treated with allopurinol, who developed acute onset of oral lichenoid lesions, involving bilaterally the buccal mucosa, the tongue and the labial mucosa. Histopathology was consistent with a lichen planus or a drug-induced lichenoid reaction. Improvement of the patient’s condition after withdrawal of allopurinol confirmed the lichenoid nature of the lesion. Remission was complete after a few weeks. Discussion: Although unusual, allopurinol may induce a lichenoid drug reaction. These reactions may mimic clinically and histopathologically idiopathic lichen planus. Improvement or complete regression of the lesions may be attempted to confirm the diagnosis. According to the latest WHO recommendations, these lesions have a potential for malignant transformation.

The burden of subclinical intra-articular inflammation in gout

OBJECTIVE

To assess the burden of subclinical intra-articular inflammation using ultrasound in people with gout.

METHODS

A pilot, prospective longitudinal cohort of 28 participants with gout were examined twice, once during a gout flare (n = 25) and then during an inter-critical phase (n = 27). At each visit, a 52 joint count was done followed by ultrasound examination for detection of intra-articular power Doppler (PD) signal. Clinically active joints were defined as tender and swollen. Data was collected on patient reported gout pain - visual analog scale (VAS) (painVAS), physician global VAS (physicianVAS), Health Assessment Questionnaire (HAQ), serum uric acid, erythrocyte sedimentation rate (ESR), and high-sensitivity C-reactive protein (HsCRP).

RESULTS

At the flare visit, participants had a median of 1 clinically active joint (interquartile range [IQR] 1-2), and a median of 5 joints with a PD score ≥ 2 (IQR 4-10, P < .001). At the inter-critical visit, participants reported an median of 0 clinically active joints (IQR 0-0), and a median of 4 joints with a PD score ≥ 2 (IQR 3-7, P < .001). Physician VAS (5.69 vs 3.40, P < .001), painVAS (6 vs 0, P < .001), HAQ (0.75 vs 0.12, P = .032), and ESR (29 vs 13.5 mm/h, P = .02) were higher at the acute visit, but HsCRP levels were similar (8.88 vs 5.15 mg/L, P = .062).

CONCLUSION

This pilot study established the presence of subclinical intra-articular inflammation in gout at both acute and inter-critical phases. Despite the apparent resolution of symptoms after an acute flare, a relatively high proportion of joints had subclinical inflammation in the inter-critical visit. The long-term implications of untreated subclinical joint inflammation are not clear.

Impact of Lesinurad and allopurinol on experimental Hyperuricemia in mice: biochemical, molecular and Immunohistochemical study

BACKGROUND

Hyperuricemia is an abnormal increase in uric acid levels in the blood. It is the cause of gout that manifested by inflammatory arthritis and painful disable. Therefore, current study evaluated the potential ameliorative impact of Lesinurad and Allopurinol on the kidneys of hyperuricemic mice at the biochemical, molecular and cellular levels.

METHODS

Lesinurad and allopurinol alone or in combination were orally administered to hyperuricemic and control mice for seven consecutive days. Levels of uric acid and blood urea nitrogen, along with antioxidants and inflammatory cytokines (IL-1β and TNF-α) were measured in the serum. The mRNA expression of mouse urate anion transporter-1, glucose transporter 9, organic anion transporters, in renal tissues were examined using quantitative real time PCR. Simultaneously, the immunoreactivity of transforming growth factor-beta 1 was examined immunohistochemically.

RESULTS

Lesinurad and allopurinol administration resulted in significant decrease in serum levels of uric acid, blood urea nitrogen, xanthine oxidase activity, catalase, glutathione peroxidase and inflammatory cytokines (IL-1β and TNF-α) reported in hyperuricemic mice. Both partially reversed oxonate-induced alterations in renal mURAT-1, mGLUT-9, mOAT-1 and mOAT-3 expressions, as well as alterations in the immunoreactivity of TGF- β1, resulting in the increase of renal uric acid secretion and excretion. The combined administration of lesinurad and ALP restored all altered parameters in a synergistic manner, improving renal function in the hyperuricemic mouse model employed.

CONCLUSION

This study confirmed synergistic ameliorative hypouricemic impact of both lesinurad and allopurinol in the treatment of hyperuricemia in mice at the biochemical, molecular and cellular levels.

Failure to reach uric acid target of <0.36 mmol/L in hyperuricaemia of gout is associated with elevated total and cardiovascular mortality

Objective

To determine the impact of achieving serum uric acid (sUA) of <0.36 mmol/L on overall and cardiovascular (CV) mortality in patients with gout.

Methods

Prospective cohort of patients with gout recruited from 1992 to 2017. Exposure was defined as the average sUA recorded during the first year of follow-up, dichotomised as ≤ or >0.36 mmol/L. Bivariate and multivariate Cox proportional hazards models were used to determine mortality risks, expressed HRs and 95% CIs.

Results

Of 1193 patients, 92% were men with a mean age of 60 years, 6.8 years' disease duration, an average of three to four flares in the previous year, a mean sUA of 9.1 mg/dL at baseline and a mean follow-up 48 months; and 158 died. Crude mortality rates were significantly higher for an sUA of ≥0.36 mmol/L, 80.9 per 1000 patient-years (95% CI 59.4 to 110.3), than for an sUA of <0.36 mmol/L, 25.7 per 1000 patient-years (95% CI 21.3 to 30.9). After adjustment for age, sex, CV risk factors, previous CV events, observation period and baseline sUA concentration, an sUA of ≥0.36 mmol/L was associated with elevated overall mortality (HR=2.33, 95% CI 1.60 to 3.41) and CV mortality (HR=2.05, 95% CI 1.21 to 3.45).

Conclusions

Failure to reach a target sUA level of 0.36 mmol/L in patients with hyperuricaemia of gout is an independent predictor of overall and CV-related mortality. Targeting sUA levels of <0.36 mmol/L should be a principal goal in these high-risk patients in order to reduce CV events and to extend patient survival.

Case with long-standing gout showing various ultrasonographic features caused by monosodium urate monohydrate crystal deposition

Gout, which is characterized by the deposition of monosodium urate monohydrate (MSU) in the synovial fluid and other tissues, is the most common form of inflammatory arthritis. Unlike the easily recognized acute and monoarticular gouty arthritis, advanced gout induces multiple finger joint disorders and may sometimes mimic rheumatoid arthritis (RA) or vice versa. The gold standard for gout diagnosis is the identification of MSU crystals via aspiration in the symptomatic joints or nodules; however, its feasibility and specificity may be inadequate. Recently, there have been important advances in imaging techniques, assisting in the non-invasive diagnosis of gout. Ultrasonography (US) has been known to have the ability to detect deposition of MSU crystals in patients with gout. Herein, we report an evocative case of long-standing gout with precisely detected specific US features indicating MSU crystal deposition and inflammation in multiple joints. Comprehensive US assessment included the bone, hyaline cartilage, soft tissue, subcutaneous nodules and tendon; we also discriminated gouty arthritis from RA.

Highly Acylated Anthocyanins from Purple Sweet Potato ( Ipomoea batatas L.) Alleviate Hyperuricemia and Kidney Inflammation in Hyperuricemic Mice: Possible Attenuation Effects on Allopurinol

Allopurinol is the first-line medication for hyperuricemia treatment. However, severe drug-related adverse effects have often been reported among patients who received allopurinol administration. This study is aimed at evaluating the possible attenuation effects of highly acylated anthocyanins from purple sweet potato (HAA-PSP) on hyperuricemia and kidney inflammation in hyperuricemic mice treated with allopurinol. In comparison with 5 mg kg^-1 allopurinol used alone, the combination of 25 mg kg^-1 HAA-PSP and 2.5 mg kg^-1 allopurinol could not only reduce serum uric acid level in hyperuricemic mice but also attenuate the kidney damage, as indicated by the level of serum biomarkers as well as histopathological examination. The inflammatory response was partially mitigated by inhibiting the protein expression of typical cytokines in the kidney. Our findings provide new evidence for the supplementary therapeutic potential of HAA-PSP with allopurinol on hyperuricemia and inflammation-related syndromes. Moreover, this study provides a theoretical basis for assessing the potential of anthocyanin-rich foods in health.

Safety and tolerability of available urate-lowering drugs: a critical review

INTRODUCTION

Urate-lowering therapy (ULT) is the cornerstone of gout management, which is a widespread chronic illness characterized by hyperuricemia, arthropathy, tophus development, and urolithiasis. Since asymptomatic increased serum urate levels are associated with a higher risk of cardiovascular, renal and metabolic disorders, a larger use of ULTs in the general population is expected in the near future.

AREAS COVERED

This review will focus on the safety and tolerability profile of the available urate-lowering drugs: xanthine oxidase inhibitors (XOIs), uricosuric agents and injectable uricases.

EXPERT OPINION

Older drugs for ULT like allopurinol are well studied and extensively described from typical adverse effects (mild skin rash) to unusual fatal reactions, while febuxostat seems to be overall well tolerated. More evidence is required to define the safety profile of topiroxostat, arhalofenate, tranilast, and sulfinpyrazone. Furthermore, there are some unanswered questions about the pharmacological interactions of probenecid and the hepatotoxicity of benzbromarone. Despite a limited use in clinical practice, combination therapy with lesinurad or verinurad and XOI is not frequently accompanied by side effects. Rasburicase and pegloticase are usually well tolerated with some specific exceptions. Before prescribing UL drugs, physicians should take into account their safety profile tailoring the treatment on the patient characteristics.

Non-pharmacologic measures for gout management in the prospective GOSPEL cohort: Physicians' practice and patients' compliance profiles

OBJECTIVES

Gout management includes non-pharmacological measures (NPM). The main objective of this study was to describe the NPM proposed by physicians and their implementation by patients after 3-6 months. The secondary objective was to identify NPM compliance profiles among these patients.

METHODS

Ancillary observational study using the GOSPEL French cohort of 1003 patients with gout, based on questionnaires for physicians and patients at inclusion and then after 3-6 months. Patients were included by a representative sample of 398 general practitioners (GP) and 109 private-practice rheumatologists. Modifiable risk factors of hyperuricemia and proposed NPM were compared. Patient compliance profiles were identified by multiple correspondence and hierarchical clustering analysis.

RESULTS

The study included 630 patients: 80.7% were obese or overweight, 51% reported excessive alcohol consumption. Physicians identified fewer modifiable risk factors than their real prevalence in the cohort. Physicians proposed NPM to 57% of patients, particularly diet modifications (46.4%). Increasing physical activity (P < 0.0001) was the best followed NPM. The physician's influence in the decision of starting NPM was more frequent among GPs' patients (P = 0.01). Three patients' compliance profiles were identified. "Very good responders" (55.8%) implemented all the proposed NPM. "Good responders" (12.7%) had a more severe disease and followed the proposed NPM, but for alcohol consumption. "Bad responders" (31.5%) did not modify their life style: these were older patients with a very recent gout diagnosis.

CONCLUSION

More personalized care about NPM requires adapting the practitioner's approach to patients' compliance profiles, especially elderly patients with recent gout.

Gout prevalence and predictors of urate-lowering therapy use: results from a population-based study

Background

Gout has an increasing global prevalence. Underutilization of urate-lowering therapy (ULT) is thought to be common, via both suboptimal dosing and poor medication adherence. The aims of this study were to determine the prevalence of self-reported gout and the key predictors of ULT use in those with gout in a representative population survey in South Australia.

Methods

Data were obtained from the Spring 2015 South Australian Health Omnibus Survey, a multilevel, systematic, survey in a representative population sample involving face-to-face interviews (n = 3005). This study analyzed responses from respondents aged ≥ 25 years (n = 2531) about self-reported gout, ULT use, sociodemographic factors, lifestyle factors, and comorbidities, using survey weighting. Univariate and subsequent adjusted logistic regression analyses on self-reported gout were performed. ULT use was divided into three categories (never use, prior use, and current use) and these data were analyzed using a multinomial logistic regression model.

Results

Self-reported gout prevalence was 6.8% (95% CI 5.8, 7.9). The mean age of respondents with gout was 64 years (standard deviation 16) and 82% were male. As expected, older age, male gender, lower socioeconomic status (SES), and higher body mass index (BMI) were associated with gout, as were high alcohol consumption, current smoking, other forms of arthritis, and hypertension or hypercholesterolemia medication, after adjustment for sociodemographic variables. Two thirds of respondents with gout reported ULT use (36% current; 29% previous) with only 55% continuing treatment. Predictors of ULT use included male gender, low SES, and concomitant cholesterol-lowering therapy. Respondents with gout with a higher BMI were more likely to remain on ULT.

Conclusions

Despite gout being a common, potentially disabling joint disease, only 55% of respondents with gout in this study adhered to ULT. Identification of key predictors of ULT use will provide guidance on prescribing strategy in clinical practice and on the quality of gout care in the community.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1633-9) contains supplementary material, which is available to authorized users.

A Qualitative Study Exploring Perceptions of Patients With Gout

Gout is a chronic disease that is on a rising trend and greatly affects one’s physical and psychosocial well-being. The aim of this study was to explore patients’ perceptions of living with gout. A descriptive qualitative study was conducted and 15 adults with gout were interviewed face-to-face between December 2014 and January 2015. Thematic analysis was used to analyze the transcribed data. The experiences of patients with gout were found to revolve around four themes: emotional experiences with gout, disruptions in daily lives, interactions with doctor, and coping with gout using internal and external resources. The in-depth understanding of the patients’ experiences indicates a need to provide holistic patient education and to involve family members to create nurse-led support groups and to raise public awareness regarding gout.

Burden of gout in the Nordic region, 1990-2015: findings from the Global Burden of Disease Study 2015

OBJECTIVE

To explore the burden of gout in the Nordic region, with a population around 27 million in 2015 distributed across six countries.

METHOD

We used the findings of the 2015 Global Burden of Diseases study to report prevalence and disability associated with gout in the Nordic region.

RESULTS

From 1990 to 2015, the number of prevalent gout cases rose by 30% to 252 967 [95% uncertainty interval (UI) 223 478‒287 288] in the Nordic region. In 2015, gout contributed to 7982 (95% UI 5431‒10 800) years lived with disability (YLDs) in the region, an increase of 29% (95% UI 24‒35%) from 1990. While the crude YLD rate of gout increased by 12.9% (95% UI 7.8‒18.1%) between 1990 and 2015, the age-standardized YLD rate remained stable. Gout was ranked as the 63rd leading cause of total YLDs in the region in 2015, with the highest rank in men aged 55-59 years (38th leading cause of YLDs). The corresponding rank at the global level was 94. Of 195 countries studied, four Nordic countries [Greenland (2nd), Iceland (12th), Finland (14th), and Sweden (15th)] were among the top 15 countries with the highest age-standardized YLD rate of gout.

CONCLUSION

The burden of gout is rising in the Nordic region. Gout's contribution to the total burden of diseases in the region is more significant than the global average. Expected increases in gout burden owing to population growth and ageing call for stronger preventive and therapeutic strategies for gout management in Nordic countries.

Anti-hyperuricemic and nephroprotective effects of extracts from Chaenomeles sinensis (Thouin) Koehne in hyperuricemic mice

CSF-E possesses potent anti-hyperuricemic through inhibiting XOD activity.

What Outcomes are Important for Gout Patients? In-Depth Qualitative Research into the Gout Patient Experience to Determine Optimal Endpoints for Evaluating Therapeutic Interventions

Background and Objectives

Characterized by sudden onset of severe joint pain, swelling, redness, and tenderness to touch, gout ‘flare ups’ have a substantial impact on quality of life (QoL). This research employed a patient-centered approach to explore the symptoms and impacts of gout, and assess the content validity of existing patient-reported outcomes (PROs).

Methods

Qualitative interviews were conducted with 30 US gout patients (non-tophaceous: n = 20, tophaceous: n = 10) and five expert rheumatologists. Each interview included both concept elicitation (CE) questioning to learn about the patient experience and cognitive debriefing to assess the content validity of three PRO instruments (HAQ-DI, GAQ, and TIQ-20). Nine of the patients provided further real-time qualitative data through a smart phone application. All qualitative data were subject to thematic analysis using Atlas.ti. Two patient advisors and three expert clinicians were engaged as advisors at key stages throughout the research.

Results

Interview and real-time data identified the same core symptoms and proximal impact concepts. Severe pain (typically in joints of extremities) was described as the cardinal symptom, often accompanied by swelling, redness, heat, sensitivity to touch, and stiffness. Domains of QoL impacted included physical functioning, sleep, daily activities, and work. The PRO instruments were generally well-understood by patients, but each included items with questionable relevance to at least some of the sample, dependent on the specific joints affected.

Conclusions

Gout patients experience severe pain in affected joints, resulting in substantial limitations in physical functioning. Both the HAQ-DI and the TIQ-20 are useful for specific research purposes in the gout population, although modifications are recommended.

Electronic supplementary material

The online version of this article (doi:10.1007/s40271-016-0184-x) contains supplementary material, which is available to authorized users.

Association of NLRP3 polymorphisms with susceptibility to primary gouty arthritis in a Chinese Han population

The NLRP3-interleukin1β (IL1β) signaling pathway is involved in monosodium urate (MSU)-mediated inflammation. The aim of this present study was to determine whether single nucleotide polymorphisms (SNPs) in the NLRP3 gene are associated with susceptibility to gouty arthritis (GA) and whether these SNPs alter the expression of components of the NLRP3-IL1β signaling pathway. The rs10754558, rs4612666, and rs1539019 SNPs were detected in 583 patients with GA and 459 healthy subjects. NLRP3 and IL1β mRNA levels in peripheral blood mononuclear cells (PBMCs) and serum IL1β levels were measured in different genotype carriers, and correlations between the NLRP3 SNPs and NLRP3 mRNA, IL1β mRNA, and serum IL1β levels were investigated. The GG genotype of NLRP3 rs10754558 was found to be significantly associated with patients with GA compared to the healthy control subjects via multivariate logistic regression analysis (adjusted OR = 2.68, P = 0.006). The CGA haplotypes were independently associated with patients with GA compared to the healthy control subjects (adjusted OR = 1.968, P = 0.02). The levels of NLRP3 mRNA, IL1β mRNA, and serum IL1β in the patients with GA were significantly different among the three genotypes of rs10754558 (all P < 0.01). The GG genotype of rs10754558 and the CGA haplotype of rs4612666-C, rs10754558-G, and rs1539019-A are both independent risk factors for primary GA development. The rs10754558 polymorphism might participate in regulating immune and inflammation responses in patients with GA by influencing the expression of components of the NLRP3 inflammasome. Future multicenter studies aimed at replicating these findings in an independent population as well as functional tests will aid in further defining the role of these SNPs in the development of GA.

Associated factors with functional disability and health-related quality of life in Chinese patients with gout: a case-control study

Background

Gout is a painful, inflammatory disease that may cause decreased function and health-related quality of life (HRQoL). Limited study did not take the influence of gout characteristics and anxiety on HRQoL into consideration and there are no studies associated with functional disability in individuals with gout from China. This study aims to investigate the related factors of functional disability and HRQoL in gout patients recruited from China.

Methods

A total of 226 consecutive gout patients and 232 age- and gender-matched healthy individuals were involved in the study. A series of questionnaires (the Short Form 36 health survey, the Patient Health Questionnaire, the Generalized Anxiety Disorder questionnaire, the 10 cm Visual Analog Scale, and the Health Assessment Questionnaire-Disability Index) were applied. Blood samples were taken to examine the level of serum uric acid. Independent samples t-tests, Chi square tests, U test, Spearman rank correlation, logistic regression modeling, and linear regression were used to analyze the data.

Results

After adjusted demographic variables, individuals with gout have poorer HRQoL compared to healthy controls. Univariate tests presented that patients with functional disability had longer disease duration, more frequent flares/last year, more severe total pain, more number of tophi, higher degree of depression and anxiety, with a trend toward diabetes, the treatment of colchicine and corticosteroids use, compared to patients without functional disability. Meanwhile, place of residence, hypertension, DM, disease duration, cardiovascular disease, number of flares/last year, total pain, more number of tophi, presence of tender joints, depression, anxiety, currently using colchicine and corticosteroids were correlated significantly with HRQoL. Additionally, multiple regression analysis identified severe pain, depression, and colchicine use as predictors of functional disability. Cardiovascular disease, total pain, number of flares/last year, presence of tender joints, depression, anxiety, colchicine and corticosteroids use contributed to low HRQoL.

Conclusions

After adjusted demographic variables, gout subjects have poorer HRQoL compared to healthy controls. Chinese gout population experiencing poor HRQoL and functional disability were likely to suffer from gout-related features and psychological problems. The results underscore the need of effective interventions including psychological nursing and appropriate treatment approaches to reduce their functional disability and improve their HRQoL.

Weight loss for overweight and obese individuals with gout: a systematic review of longitudinal studies

OBJECTIVES

Weight loss is commonly recommended for gout, but the magnitude of the effect has not been evaluated in a systematic review. The aim of this systematic review was to determine benefits and harms associated with weight loss in overweight and obese patients with gout.

METHODS

We searched six databases for longitudinal studies, reporting the effect of weight loss in overweight/obese gout patients. Risk of bias was assessed using the tool Risk of Bias in Non-Randomised Studies of Interventions. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation.

RESULTS

From 3991 potentially eligible studies, 10 were included (including one randomised trial). Interventions included diet with/without physical activity, bariatric surgery, diuretics, metformin or no intervention. Mean weight losses ranged from 3 kg to 34 kg. Clinical heterogeneity in study characteristics precluded meta-analysis. The effect on serum uric acid (sUA) ranged from -168 to 30 μmol/L, and 0%-60% patients achieving sUA target (<360 μmol/L). Six out of eight studies (75%) showed beneficial effects on gout attacks. Two studies indicated dose-response relationship for sUA, achieving sUA target and gout attacks. At short term, temporary increased sUA and gout attacks tended to occur after bariatric surgery.

CONCLUSIONS

The available evidence is in favour of weight loss for overweight/obese gout patients, with low, moderate and low quality of evidence for effects on sUA, achieving sUA target and gout attacks, respectively. At short term, unfavourable effects may occur. Since the current evidence consists of a few studies (mostly observational) of low methodological quality, there is an urgent need to initiate rigorous prospective studies (preferably randomised controlled trials).

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42016037937.

Metabolic Epoxidation Is a Critical Step for the Development of Benzbromarone-Induced Hepatotoxicity

Benzbromarone (BBR) is effective in the treatment of gout; however, clinical findings have shown it can also cause fatal hepatic failure. Our early studies demonstrated that CYP3A catalyzed the biotransformation of BBR to epoxide intermediate(s) that reacted with sulfur nucleophiles of protein to form protein covalent binding both in vitro and in vivo. The present study attempted to define the correlation between metabolic epoxidation and hepatotoxicity of BBR by manipulating the structure of BBR. We rationally designed and synthesized three halogenated BBR derivatives, fluorinated BBR (6-F-BBR), chlorinated BBR (6-Cl-BBR), and brominated BBR (6-Br-BBR), to decrease the potential for cytochrome P450-mediated metabolic activation. Both in vitro and in vivo uricosuric activity assays showed that 6-F-BBR achieved favorable uricosuric effect, while 6-Cl-BBR and 6-Br-BBR showed weak uricosuric efficacy. Additionally, 6-F-BBR elicited much lower hepatotoxicity in mice. Fluorination of BBR offered advantage to metabolic stability in liver microsomes, almost completely blocked the formation of epoxide metabolite(s) and protein covalent binding, and attenuated hepatic and plasma glutathione depletion. Moreover, the structural manipulation did not alter the efficacy of BBR. This work provided solid evidence that the formation of the epoxide(s) is a key step in the development of BBR-induced hepatotoxicity.

Cardiovascular effects of urate-lowering therapies in patients with chronic gout: a systematic review and meta-analysis

Objectives

To determine if urate-lowering treatment (ULT) in gout can reduce cardiovascular (CV) outcomes.

Methods

Randomized trials were searched for treatment with ULT in gout. Eligible trials had to report CV safety of a ULT. Potential medications included allopurinol, febuxostat, pegloticase, rasburicase, probenecid, benzbromarone, sulphinpyrazone, losartan, fenofibrate and sodium-glucose linked transporter 2 inhibitors.

Results

A total of 3084 citations were found, with 642 duplicates. After the primary screen, 35 studies were selected for review. Several trials did not report CV events. Six were not randomized controlled trials (RCTs). Four studies reported no events in either intervention arm while the other four had 40 events in the febuxostat group ( n = 3631) and 5 in allopurinol group ( n = 1154). Overall, the pooled analysis did not show a significant difference between the two [febuxostat vs allopurinol: relative risk (RR) 1.69 (95% CI 0.54, 5.34), P = 0.37]. CV events did not decrease over time. Comparing shorter studies (<52 weeks) to longer ones did not reveal any statistical differences. However, in long-term studies with febuxostat vs allopurinol, results were nearly significant, with more CVE occurring with febuxostat treatment. Comparing any ULT to placebo (eight studies, n = 2221 patients) did not demonstrate a significant difference in non-Anti-Platelet Trialists' Collaboration events [any ULT vs placebo: RR 1.47 (95% CI 0.49, 4.40), P = 0.49] or all-cause mortality [any ULT vs placebo: RR 1.45 (95% CI 0.35, 5.77), P = 0.60].

Conclusion

RCT data do not suggest differences in CV events among ULTs in gout. Trials had few events despite high-risk patients being enrolled and may have been too short to show CV reduction by controlling inflammatory attacks and lowering uric acid.

Microwave Heating of Crystals with Gold Nanoparticles and Synovial Fluid under Synthetic Skin Patches

Gout is a disease with elusive treatment options. Reduction of the size of l-alanine crystals as a model crystal for gouty tophi with the use of a monomode solid-state microwave was examined as a possible therapeutic aid. The effect of microwave heating on l-alanine crystals in the presence of gold nanoparticles (Au NPs) in solution and synovial fluid (SF) in a plastic pouch through a synthetic skin patch was investigated. In this regard, three experimental paradigms were employed: Paradigm 1 includes the effect of variable microwave power (5-10 W) and variable heating time (5-60 s) and Au NPs in water (20 nm size, volume of 10 μL) in a plastic pouch (1 × 2 cm² in size). Paradigm 2 includes the effect of a variable volume of 20 nm Au NPs in a variable volume of SF up to 100 μL in a plastic pouch at a constant microwave power (10 W) for 30 s. Paradigm 3 includes the effect of constant microwave power (10 W) and microwave heating time (30 s), constant volume of Au NPs (100 μL), and variable size of Au NPs (20-200 nm) placed in a plastic pouch through a synthetic skin patch. In these experiments, an average of 60-100% reduction in the size of an l-alanine crystal (initial size = 450 μm) without damage to the synthetic skin or increasing the temperature of the samples beyond the physiological range was reported.

Prevalence of Chondrocalcinosis in Patients above 50 Years and the Relationship with Osteoarthritis

BACKGROUND

Some studies showed a relation between chondrocalcinosis and osteoarthritis (OA). Hence, considering the importance of chondrocalcinosis diagnosis andnecessity for its integration with OA, the current study aims at investigating prevalence of chondrocalcinosis in patients above 50 years admitted to Isfahan Al-Zahra Medical Center and its relationship with OA.

MATERIALS AND METHODS

In a cross-sectional study, 600 patients who referred to the radiology units of Al-Zahra Hospital for radiography of different joints were studied during 2013-2014. The patients images were studied for chondrocalcinosis and OA by a radiologist and also examined clinically and results of imaging by an expert rheumatologist. The prevalence of chondrocalcinosis and it relation with OA was determined by Statistical Package for Social Sciences software and using of Chi-square and t-test.

RESULTS

23 patients under study had chondrocalcinosis (3.83%). patients with chondrocalcinosis had higher age average, and they were in age group of 70 years and older, but no significant difference was observed regarding the prevalence of the disease in both genders. Chondrocalcinosis prevalence in terms of body mass index showed significant differences (P = 0.001). All patients with chondrocalcinosis had a history of joint disease and prevalence of chondrocalcinosis in terms of joint disease history showed a significant difference (P < 0.001).

CONCLUSION

Prevalence of chondrocalcinosis is relatively high in the Iranian population of 70 years and older. Hence, more investigation considering to the diagnosis of chondrocalcinosis among patients with OA is very important.

Oral uricase eliminates blood uric acid in the hyperuricemic pig model

An elevated level of serum uric acid-hyperuricemia, is strongly associated with the development of gout and chronic kidney disease (CKD) which is often accompanied by a significantly reduced glomerular filtration rate (GFR). In the present study, we investigated the extra-renal elimination of uric acid via the intestine in a healthy pig model and the effect of oral uricase therapy on plasma uric acid concentrations in pigs with induced hyperuricemia and CKD. The experiment was conducted on eleven, ten-week-old pigs (n = 11). The porcine model of CKD was developed by performing 9/10 nephrectomy surgery on eight pigs. A stable model of hyperuricemia was established in only five of the eight nephrectomized pigs by frequent injections of uric acid (UA) into the jugular vein. All pigs (three healthy pigs and five CKD pigs) were operated for implantation of jugular vein catheters and the three healthy pigs also had portal vein catheters inserted. Blood uric acid concentrations were measured spectrophotometrically, using the Uric Acid Assay Kit (BioAssay Systems, Hayward, USA). The piglets with CKD received orally administered uricase (treatment) and served as their own controls (without uricase supplementation). Oral uricase therapy significantly decreased plasma uric acid concentrations in pigs with CKD, whereas hyperuricemia was observed in the pigs whilst not being treated with uricase. Urinary uric acid excretion was similar during both the treatment and control periods during the first 8 h and 24 h after UA infusions in the CKD pigs. To demonstrate the elimination of UA via the intestine, the healthy pigs were infused with UA into the jugular vein. The blood collected from the jugular vein represents circulating UA concentrations and the blood collected from the portal vein represents the concentration of UA leaving the intestine. The final (after 2 h) concentration of UA was significantly lower in blood collected from the portal vein compared to that collected from the jugular vein (3.34 vs. 2.43 mg/dL, respectively, p = 0.024). The latter allows us to suggest that UA is eliminated from the blood via the gut tissue.