A Systematic Review of the Economic and Humanistic Burden of Gout

Hyperuricaemia and gout in the Pacific

Gout is the most common form of inflammatory arthritis in adults worldwide. There has been a steady increase in prevalence, which varies across different geographic areas and is high in the Indigenous (First Nations) peoples of the Pacific region. Palaeo-archaeological studies demonstrate that gout was present in the Pacific region prior to European colonization, which is suggestive of genetic predisposition. Genetic risk factors, including population-specific genetic variants and genetic variants shared across populations, particularly those influencing urate transporters, have been identified in Indigenous peoples of the Pacific that partly explain the earlier age of onset of gout. Indigenous peoples of the Pacific experience severe gout, with frequent flares, high hospitalization rates and tophaceous gout, all aggravated by socio-cultural factors. Despite a specific need for effective gout management, Indigenous peoples of the Pacific are under-represented in gout research and inequities in care continue. Indigenous peoples-led, holistic gout management programmes are systematically and urgently required in this region, where gout is a major public health issue. Importantly, a foundation of cultural safety is necessary to underpin such programmes.

Exploration of the Interrelationship Between Serum Uric Acid, Gout, and Cardiac, Renal, and Metabolic Conditions in Middle Aged and Older People

BACKGROUND

Cardiac, renal, and metabolic (CRM) conditions are major causes of morbidity and mortality globally. This study aims to explore the relationship between serum uric acid (SUA), hyperuricemia, gout, and CRM conditions in middle-aged and elderly populations.

METHODS

Sample 1 included participants from CHARLS (China Health and Retirement Longitudinal Study, n=9341), and Sample 2 from NHANES (National Health and Nutrition Examination Survey, unweighted n=17 913; weighted n=115 646 390). Ordinal logistic regression, Cox regression, and restricted cubic spline analyses were used to assess the relationship between SUA, hyperuricemia, gout, and CRM conditions. A 2-sample Mendelian randomization analysis was conducted to explore causal associations between SUA and CRM conditions.

RESULTS

In both samples, SUA, hyperuricemia, and gout were positively correlated with the risk of CRM conditions. Among participants with 3 or ≥1 CRM condition(s), SUA, asymptomatic hyperuricemia, and gout with poorly controlled hyperuricemia showed significant positive associations with all-cause mortality, whereas these associations were not observed in patients with gout with normal SUA levels. The restricted cubic spline analysis revealed a positive relationship between SUA levels and the risk of all-cause mortality in participants with ≥1 CRM condition(s), demonstrating a nonlinear dose-response relationship across both samples (P for nonlinearity <0.05). Mendelian randomization analysis indicated that SUA was causally associated with cardiovascular disease, chronic kidney disease, and diabetes.

CONCLUSIONS

Hyperuricemia and gout are strong predictors of increased prevalence and mortality of CRM conditions, emphasizing the importance of managing hyperuricemia and gout in these patients.

A comprehensive analysis of trends in the burden of gout in China and globally from 1990 to 2021

Gout is a prevalent metabolic disorder characterized by urate crystal accumulation in joints, leading to acute arthritis and tophi formation. Despite advancements in management, the incidence and prevalence of gout have been increasing globally, particularly in China. This study analyzed data from the Global Burden of Disease Injuries and Risk Factors Study (GBD) to evaluate trends in gout from 1990 to 2021. Statistical analyses were conducted using R and Joinpoint software, while the ARIMA model was employed for forecasting future trends. Our findings revealed a global increase in gout incidence from 93.097 per 100,000 in 1990 to 109.075 per 100,000 in 2021, with cases rising from 3,983,109 to 9,401,585. In China, incidence increased from 122.522 to 151.612 per 100,000, with cases growing from 1,182,498 to 3,079,836. Similarly, global prevalence rose from 536.545 to 653.816 per 100,000, while in China, it increased from 640.679 to 810.359 per 100,000. Disability metrics, including YLDs and DALYs, also demonstrated significant increases both globally and in China. Our analysis indicated that middle-aged and elderly populations, particularly males, are at higher risk for gout. These findings underscore the urgent need for enhanced prevention and management strategies, specifically targeting high-risk populations. Effective public health policies and interventions are crucial to mitigate the escalating burden of gout and improve the quality of life for affected individuals. This study relied on secondary data from the GBD, which may be subject to biases in data collection and reporting. Additionally, variations in diagnostic practices and healthcare access across regions could influence the accuracy of reported trends. Future research should address these limitations by incorporating primary data and exploring region-specific factors contributing to gout prevalence and incidence.

Causal relationship between inflammatory proteins, immune cells, and gout: a Mendelian randomization study

Prior research has documented the association between certain circulating inflammatory proteins/immune cells and gout. However, the reliability of these associations remains contentious due to the constraints of conventional observational methodologies. This investigation seeks to reassess the causative link between circulating inflammatory proteins/immune cells and gout through the application of Mendelian randomization (MR). The study included 3576 individuals of European ancestry with gout, immune cell data from the GWAS summary of 3757 Sardinians, and circulating inflammatory protein data from 14,824 European ancestry participants for MR analysis. The principal approach employed was inverse variance weighted analysis to investigate the causal relationship between exposure and outcomes. The results indicate that CD28 on CD39+ CD4+ T cells may be associated with a reduced risk of gout. Additionally, CD45RA+ CD28- CD8bright T cells may also be associated with a reduced risk of gout. In contrast, DN (CD4-CD8-) T cells and IL-12β may increase the risk of gout. Some inflammatory proteins and immune cells show potential causal associations with gout. Nevertheless, additional experimental verification is warranted to assess the underlying mechanisms and confirm the causative role of these immune factors in gout pathogenesis.

The decreased serum levels of interleukin-38 in patients with gout and its clinical significance

Background

Interleukin (IL)-38 is a newly discovered anti-inflammatory cytokine. However, its concentration and clinical significance in patients with gout remain unclear. This study aimed to investigate the levels of IL-38 in patients with gout and evaluate their clinical significance.

Methods

Thirty-two patients with active gout, 27 patients with inactive gout, and 20 negative controls (NCs) were included in the study. Clinical parameters, including white blood cell count, C-reactive protein, serum amyloid A, erythrocyte sedimentation rate, uric acid, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, glutamyl transpeptidase, and glycoserated serum protein, were obtained from laboratory tests of blood samples. The serum concentration of IL-38 was determined using enzyme-linked immunosorbent assay. Spearman's correlation analysis and receiver operating characteristic curve assessments were used to investigate the role and diagnostic value of IL-38 in gout.

Results

Patients with active and inactive gout exhibited significantly lower serum IL-38 levels than NCs. No significant differences were observed between the two gout groups. A negative correlation was observed between IL-38 and white blood cell counts, whereas a positive correlation was found between IL-38 and creatinine levels. Furthermore, IL-38, either alone or in combination with uric acid, demonstrated substantial diagnostic potential.

Conclusion

The findings suggest that the decreased serum levels of IL-38 in patients with gout compared to that in NCs indicates that IL-38 may have immunomodulatory effects on gout inflammation and possesses clinical application value.

Global, regional, and national burden of gout, 1990-2020, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021

BACKGROUND

Gout is an inflammatory arthritis manifesting as acute episodes of severe joint pain and swelling, which can progress to chronic tophaceous or chronic erosive gout, or both. Here, we present the most up-to-date global, regional, and national estimates for prevalence and years lived with disability (YLDs) due to gout by sex, age, and location from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, as well as forecasted prevalence to 2050.

METHODS

Gout prevalence and YLDs from 1990 to 2020 were estimated by drawing on population-based data from 35 countries and claims data from the USA and Taiwan (province of China). Nested Bayesian meta-regression models were used to estimate prevalence and YLDs due to gout by age, sex, and location. Prevalence was forecast to 2050 with a mixed-effects model.

FINDINGS

In 2020, 55·8 million (95% uncertainty interval 44·4-69·8) people globally had gout, with an age-standardised prevalence of 659·3 (525·4-822·3) per 100 000, an increase of 22·5% (20·9-24·2) since 1990. Globally, the prevalence of gout in 2020 was 3·26 (3·11-3·39) times higher in males than in females and increased with age. The total number of prevalent cases of gout is estimated to reach 95·8 million (81·1-116) in 2050, with population growth being the largest contributor to this increase and only a very small contribution from the forecasted change in gout prevalence. Age-standardised gout prevalence in 2050 is forecast to be 667 (531-830) per 100 000 population. The global age-standardised YLD rate of gout was 20·5 (14·4-28·2) per 100 000 population in 2020. High BMI accounted for 34·3% (27·7-40·6) of YLDs due to gout and kidney dysfunction accounted for 11·8% (9·3-14·2).

INTERPRETATION

Our forecasting model estimates that the number of individuals with gout will increase by more than 70% from 2020 to 2050, primarily due to population growth and ageing. With the association between gout disability and high BMI, dietary and lifestyle modifications focusing on bodyweight reduction are needed at the population level to reduce the burden of gout along with access to interventions to prevent and control flares. Despite the rigour of the standardised GBD methodology and modelling, in many countries, particularly low-income and middle-income countries, estimates are based on modelled rather than primary data and are also lacking severity and disability estimates. We strongly encourage the collection of these data to be included in future GBD iterations.

FUNDING

Bill & Melinda Gates Foundation and the Global Alliance for Musculoskeletal Health.

Potential clinical value of serum interleukin-41 levels in patients with acute gout

BACKGROUND

Gout is a common metabolic rheumatic disease, and there have been no reports on the serum levels of interleukin (IL)-41 in gout patients. The purpose of this study was to therefore determine the expression of IL-41 in the serum of gout patients.

METHODS

Eighty-one participants were enrolled in this study, including 34 patients with acute gout, 27 gout patients in remission, and 20 healthy controls (HCs). Baseline data were obtained through interviews and laboratory parameters were acquired via blood sample testing. We measured serum IL-41 concentrations with an enzyme-linked immunosorbent assay, and executed Spearman's correlation analysis to investigate the correlation between IL-41 and other parameters, and the diagnostic value for IL-41 was demonstrated using a receiver operating characteristic curve. Multivariate analysis was conducted by adopting logistic regression.

RESULTS

Serum IL-41 concentrations in acute-gout patients were higher than those in HCs and there was no significant difference in serum IL-41 levels between remission gout patients and HCs. In addition, IL-41 was positively correlated with white blood cell count, erythrocyte sedimentation rate, and C-reactive protein and serum amyloid A concentrations, while it was negatively correlated with triglyceride levels. IL-41 showed good diagnostic value for gout, and the combination of IL-41 and uric acid produced a superior diagnostic value. We also noted that IL-41 was an independent risk factor for acute gout.

CONCLUSIONS

This study revealed that serum IL-41 was elevated in patients with acute gout, and suggests that IL-41 may constitute a novel diagnostic marker for acute gout.

Association between serum uric acid levels of patients with gout and their complications and examination fees: A cross-sectional analysis

OBJECTIVE

Correlation influence factor analysis of gout patients' serum uric acid (SUA) levels, their examination fees, and various complications were explored.

METHODS

From January 2017 to December 2021, 17 666 patients with gout were obtained. Conduct quartile grouping according to gout patients' SUA levels was used to compare the differences between groups in terms of examination fees and complications. Kernel density estimation method was adopted to analyze the data distribution, Spearman and Mantel-Haenszel χ² tests were used to analyze the correlation between SUA levels and examination fees and complications. Binary logistic regression analysis was used to analyze the correlation influence factor between SUA levels and complications.

RESULTS

Of the 17 666 gout cases, 85.46% were male. Among them, 7637 (43.23%) were inpatients and 10 029 (56.77%) were outpatients. Compared with outpatients, age, SUA levels, and examination fees were significantly higher, and there were more complications among inpatients (P < 0.05). Correlation analysis revealed that outpatients and SUA levels of patients with gout were positively correlated with examination fees, cardiovascular diseases, pulmonary diseases, liver diseases, and kidney diseases (P < 0.01). Binary logistic regression analysis showed that SUA level is an independent influence factor for cardiovascular diseases, pulmonary diseases, liver diseases, and kidney diseases (odds ratio [95% confidence interval]: 1.002 [1.002-1.002], 1.001 [1.000-1.001], 1.003 [1.002-1.003], and 1.001 [1.001-1.002], respectively).

CONCLUSIONS

As SUA levels increased, examination fees, cardiovascular disease, pulmonary disease, liver disease, and kidney disease complications increased. SUA level is an independent influence factor for the combination of gout with cardiovascular diseases, pulmonary diseases, liver diseases, and kidney diseases.

Genetic Risk, Adherence to a Healthy Lifestyle, and Hyperuricemia: The TCLSIH Cohort Study

BACKGROUND

Genetic factors have been associated with hyperuricemia in large studies, but the extent to which this can be offset by a healthy lifestyle is unknown. This study aimed to examine whether healthy lifestyle could reduce hyperuricemia risk among individuals with different genetic profiles.

METHODS

We defined a lifestyle score using body mass index, smoking, alcohol consumption, physical activities, and diets in 2796 unrelated individuals from the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study. Polygenic risk scores (PRS) were constructed based on uric acid loci. Associations of combined lifestyle factors and genetic risk and incident hyperuricemia were estimated using Cox proportional hazard regression.

RESULTS

Of 2796 individuals, 747 participants (26.7%) developed hyperuricemia. Genetic risk and lifestyle were predictors of incident events, and they showed an interaction for the outcome. Compared with high PRS, low PRS reduced risk of incident hyperuricemia by 40%, and compared with unhealthy lifestyle, healthy lifestyle reduced risk of incident hyperuricemia by 41%. Compared with unhealthy lifestyle and high genetic risk, adherence to healthy lifestyle was associated with a 68% (95% confidence interval, 44%-81%) lower risk of hyperuricemia among those at a low genetic risk.

CONCLUSIONS

In this prospective cohort study, we observed an interaction between genetics and lifestyle and the risk of hyperuricemia. The public health implication is that a healthy lifestyle is important for hyperuricemia prevention, especially for individuals with high genetic risk scores.

Environmental factors and risk of gout

Gout is a chronic disease with inflammatory arthritis caused by monosodium urate (MSU) crystals deposition, an elevated serum urate level (hyperuricaemia) is the critical factor leading to MSU crystals deposition and promoting the progression of gout. The onset and development of gout is generally the result of multiple factors, such as diet, heredity and environmental factors. Although genetics and diet are thought to play as major factors, a growing body of research evidence has highlighted that environmental factors also play a significant role in the onset and exacerbation of gout. Recent studies have shown that air pollutants such as particulate matter, sulfur dioxide (SO₂) and carbon monoxide (CO) may increase the risk of hospitalizations for gout, and that the changes in temperature and humidity may affect uric acid (UA) levels. There is also seasonal trend in gout. It has been demonstrated that environmental factors may induce or accelerate the production and release of pro-inflammatory mediators, causing an unbalance oxidative stress and systemic inflammation, and then participating in the overall process or a certain link of gout. Moreover, several environmental factors have shown the ability to induce the production urate and regulate the innate immune pathways, involving in the pathogenesis of gout. Nevertheless, the role of environmental factors in the etiology of gout remains unclear. In this review, we summarized the recent literatures and aimed to discuss the relationship between environmental factors (such as microclimate, season, ambient/indoor air pollution and extreme weather) and gout. We further discussed the inflammatory mechanisms of environmental factors and gout and the comprehensive effects of environmental factors on gout. We also made a prospect of the management and treatment of gout, with special consideration to environmental factors associated with gout.

Gout and Hospital Admission for Ambulatory Care-Sensitive Conditions: Risks and Trajectories

OBJECTIVE

To investigate the risks and trajectories of hospital admission for ambulatory care-sensitive conditions (ACSCs) in gout.

METHODS

Among individuals aged 35 years to 85 years residing in Skåne, Sweden, in 2005, those with no doctor-diagnosed gout during 1998 to 2005 (n = 576,659) were followed from January 1, 2006, until a hospital admission for an ACSC, death, relocation outside Skåne, or December 31, 2016. Treating a new gout diagnosis (International Classification of Diseases, 10th revision, code M10) as a time-varying exposure, we used Cox proportional and additive hazard models to estimate the effects of gout on hospital admissions for ACSCs. We investigated the trajectory of hospital admissions for ACSCs from 3 years before to 3 years after gout diagnosis using generalized estimating equations and group-based trajectory modeling in an age-and sex-matched cohort study.

RESULTS

Gout was associated with a 41% increased rate of hospital admission for ACSCs (hazard ratio 1.41, 95% CI 1.35-1.47), corresponding to 121 (95% CI 104-138) more hospital admissions for ACSCs per 10,000 person-years compared with those without gout. Our trajectory analysis showed that higher rates of hospital admission for ACSCs among persons with gout were observed from 3 years before to 3 years after diagnosis, with the highest prevalence rate ratio (2.22, 95% CI 1.92-2.53) at the 3-month period after diagnosis. We identified 3 classes with distinct trajectories of hospital admissions for ACSCs among patients with gout: almost none (88.5%), low-rising (9.7%), and moderate-sharply rising (1.8%). The Charlson Comorbidity Index was the most important predictor of trajectory class membership.

CONCLUSION

Increased risk of hospital admissions for ACSCs in gout highlights the need for better management of the disease through outpatient care, especially among foreign-born, older patients with comorbidities.

The Interaction Between Dietary Fructose and Gut Microbiota in Hyperuricemia and Gout

With the worldwide epidemics of hyperuricemia and associated gout, the diseases with purine metabolic disorders have become a serious threat to human public health. Accumulating evidence has shown that they have been linked to increased consumption of fructose in humans, we hereby made a timely review on the roles of fructose intake and the gut microbiota in regulating purine metabolism, together with the potential mechanisms by which excessive fructose intake contributes to hyperuricemia and gout. To this end, we focus on the understanding of the interaction between a fructose-rich diet and the gut microbiota in hyperuricemia and gout to seek for safe, cheap, and side-effect-free clinical interventions. Furthermore, fructose intake recommendations for hyperuricemia and gout patients, as well as the variety of probiotics and prebiotics with uric acid-lowering effects targeting the intestinal tract are also summarized to provide reference and guidance for the further research.

[Analysis of the effect of asymptomatic hyperuricemia on the effectiveness after arthroscopic rotator cuff repair]

Objective

To investigate the effect of asymptomatic hyperuricemia on the effectiveness of arthroscopic rotator cuff repair.

Methods

The clinical data of 80 patients who underwent arthroscopic rotator cuff repair and met the selection criteria between March 2018 and December 2019 were retrospectively analyzed. According to the serum uric acid level, the patients were divided into hyperuric acid group (46 cases, the serum uric acid level was more than 417 μmol/L in males and was more than 357 μmol/L in females) and normal group (34 cases, serum uric acid level was lower than the above standard). There was no significant difference in gender, age, side, body mass index, blood glucose level, total cholesterol level, rotator cuff tear size, and preoperative shoulder motion, visual analogue scale (VAS) score, University of California-Los Angeles (UCLA) score, Constant score, American Shoulder and Elbow Surgeons (ASES) score, and other general data between the two groups ( P>0.05). The range of motion of abduction, forward flexion, and external rotation at 90° abduction were recorded and compared between the two groups before operation and at last follow-up; the improvement of shoulder pain was evaluated by VAS score; the improvement of shoulder function was evaluated by UCLA score, Constant score, and ASES score; and the shoulder joint MRI grade was evaluated according to Sugaya evaluation criteria.

Results

All patients were followed up 9-16 months, with an average of 11.9 months; there was no significant difference in the follow-up time between the two groups ( t=0.968, P=0.336). There were 2 cases of retear in the hyperuric acid group (including 1 case of severe tear) and 1 case of light retear in the normal group. The remaining patients in the two groups had no early-related complications. At last follow-up, the range of motion of the shoulder joints (abduction, forward flexion, external rotation at 90° abduction), VAS score, UCLA score, Constant score, and ASES score of the two groups were significantly improved when compared with preoperative ones ( P<0.05); the above indicators in the normal group were significantly better than those in the hyperuric acid group ( P<0.05). The MRI grade of the shoulder joint in the normal group was significantly better than that in the hyperuric acid group ( Z=-2.000, P=0.045).

Conclusion

Compared with patients with normal serum uric acid level, asymptomatic hyperuricemia can lead to worse recovery after arthroscopic rotator cuff repair in patients with rotator cuff tears.

Gout in China, 1990-2017: the Global Burden of Disease Study 2017

OBJECTIVE

The aim of the study was to estimate the gout burden and risk factors in China from 1990 to 2017.

STUDY DESIGN

The Global Burden of Disease (GBD) Study uses various analytical tools and a diverse set of data sources to generate comparable estimates of deaths and mortality rates broken down by age, sex, cause, year, and geography.

METHODS

We used the results from the GBD Study 2017 to compare disability-adjusted life years (DALYs), prevalence, incidence, and risk factors of gout in China. The median of the percentage change and 95% uncertainty intervals were determined for the period between 1990 and 2017.

RESULTS

The age-standardized DALY rate, prevalence, and incidence increased 6.92%, 6.88%, and 6.16%, respectively, in China from 1990 to 2017. Although the rates of gout both globally and in China were increasing, the range of change for males in China was larger than that of the global level. All risk factors combined accounted for 30.04% of gout DALYs in 2017. The leading risk factors for gout DALYs were high body mass index and impaired kidney function, and the proportion of high body mass index increased significantly from 10.67% to 24.31%, whereas the proportion of impaired kidney function remained basically unchanged.

CONCLUSIONS

The age-standardized DALY rate, prevalence, and incidence in China have increased progressively since 1990. Increasing attention on body weight management should be prioritized for controlling the rising prevalence of gout in the young and middle-aged population.

Adherence to gout guidelines: where do we stand?

PURPOSE OF REVIEW

Although gout is a common, well-recognized, and extensively researched rheumatologic disease, it continues to be underappreciated and undertreated. Although the prevalence of gout has been rising over the past several decades, adherence to urate lowering therapy continues to be suboptimal. Recent studies have underscored the potential success of guideline-directed therapy.

RECENT FINDINGS

Adherence to gout treatment continues to be suboptimal according to multinational metaanalyses. Moreover, studies measuring adherence are prone to overestimation and each methodologic approach has intrinsic limitations. Adherence may be analyzed from the perspective of patient adherence to taking a medication, or provider adherence to treatment guidelines. In addition to considering traditional risk factors, adherence should be viewed through the lens of healthcare disparities. The RAmP-Up trial and Nottingham Gout Treatment trial demonstrate the success of protocolized gout treatment using existing guidelines for reference.

SUMMARY

Standardized gout treatment protocols should be established for all primary care and specialty practices. Two successful methods of improving adherence include using nonphysician providers to coordinate urate lowering therapy titration and monitoring serum urate. Having more frequent outpatient visits to focus on direct patient care and education has also been successful.

Patient Perspectives on Gout and Gout Treatments: A Patient Panel Discussion That Informed the 2020 American College of Rheumatology Treatment Guideline

OBJECTIVE

The objective of this study was to understand patient perspectives to inform the voting process for the 2020 American College of Rheumatology (ACR) gout treatment guideline.

METHODS

We conducted a panel meeting of eight patients with gout in Birmingham, Alabama. Patients were referred to the project by private and academic rheumatologists in the Birmingham area. All participants received orientation related to the guideline development process and evidence rating at the beginning of the meeting. With the help of a physician moderator, the patient panel reviewed nine key clinical scenarios and the supporting evidence and discussed their views and perspectives related to each. They also provided their preference for one of the two treatment options for each clinical scenario.

RESULTS

The patient panel included eight men with gout. Of these eight participants, seven received their gout care from a rheumatologist and one from a primary care physician. Patients favored more active urate-lowering therapy (ULT) management and interventional management of gout flares to achieve desired clinical outcomes, resulting in unanimous consensus on choices related to six clinical scenarios: ULT initiation in gout, treat-to-target management strategy, use of pegloticase for refractory gout, starting ULT during a gout flare, using injectable treatments (over oral) for acute gout flares, and use of febuxostat in people with cardiovascular disease.

CONCLUSION

Knowledge of patient preferences and values is valuable and was influential for the development of the 2020 ACR gout treatment guideline.

Development of a multivariable improvement measure for gout

Background

Gout is a heterogeneous inflammatory disease with numerous clinical manifestations. A composite means to assess the impact of therapy on numerous aspects of gout could be useful.

Methods

Results from patients treated with pegloticase or placebo in two randomized clinical trials and their open-label extension were assessed using a novel evidence-based Gout Multivariable Improvement Measure (GMIM) derived from previously reported criteria for remission and complete response. Improvement was defined as serum urate (sU) < 6 mg/dL and absence of flares during the preceding 3 months plus 20, 50, and 70% improvement in tophus size, patient global assessment, pain, and swollen and tender joints.

Results

Patients treated with pegloticase manifested a significantly greater GMIM20, 50, and 70 response vs those treated with placebo (GMIM20 at 6 months 37.1% vs 0%, respectively). Higher response rates were significantly more frequent in subjects with persistent urate lowering (GMIM 58.1% at 6 months) in response to pegloticase versus those with only transient urate lowering (GMIM 7.1% at 6 months). However, when the requirement for a decrease in sU to < 6 mg/dL was omitted, a substantial percentage of subjects with transient urate lowering met the GMIM clinical criteria. A sensitivity analysis indicated that gout flares contributed minimally to the model. The response measured by GMIM persisted into the open-level extension for as long as 2 years. Finally, subjects who received placebo in the randomized control trials, but pegloticase in the open-label extension, manifested GMIM responses comparable to that noted with pegloticase-treated subjects in the randomized controlled trials.

Conclusions

GMIM captures changes in disease activity in response to treatment with pegloticase and may serve as an evidence-based tool for assessment of responses to other urate-lowering therapies in gout patients.

Safety, efficacy and tolerability of a combination micronutrient and polyherbal preparation (GoutFighter TM) for gout: a single-arm open-label pilot study

BACKGROUND

To evaluate the safety, efficacy and tolerability of a combination micronutrient and polyherbal preparation (GoutFighter ^TM) for gout management.

METHODS

A single arm, open-label pilot study was conducted at the National Hospital for Traditional Medicine in Vietnam. Participants (n=35 recruited) diagnosed with chronic gout received four tablets of GoutFighter ^TM daily over a 45-day period. Efficacy was assessed by changes in pain, swelling and blood uric acid levels, with concurrent safety and tolerability assessments.

RESULTS

A total of 27 (85.2% male) participants (mean ± SD age, 54.2 ± 12.5 years; BMI, 24.2 ± 3.6 kg/m²) with gout (median [IQR], years since diagnosis 4.0 [3.0-8.0]) completed intervention. In relation to safety, there were no significant changes in vital signs, blood biochemistry or cell counts. In regard to efficacy, the degree of perceived pain and frequency of joint swelling significantly declined after 15 and 30 days of treatment, respectively, and remained so until the end of trial. Mean blood uric acid levels also declined by 25.8 μmol/L (95% CI, 3.7 to 48.0, p=0.024). Overall, the predominance of participants (96.3%) responded favorably to treatment (p<0.0001) and GoutFighter ^TM was well tolerated, with no serious adverse events.

CONCLUSION

Clinically relevant doses of GoutFighter ^TM were found to be generally safe, well-tolerated and effective for the short-term, symptomatic relief of chronic gout. GoutFighter ^TM appears to be suitable as an adjunctive treatment in lifestyle programs for gout management, and further investigation in placebo-controlled trials is therefore warranted.

CD44 Receptor Mediates Urate Crystal Phagocytosis by Macrophages and Regulates Inflammation in A Murine Peritoneal Model of Acute Gout

Gout is a chronic arthritis caused by the deposition of poorly soluble monosodium urate monohydrate (MSU) crystals in peripheral joints. Resident macrophages initiate inflammation in response to MSU mediated by NF-κB nuclear translocation and NLRP3 inflammasome activation. We investigated the role of CD44, a transmembrane receptor, in mediating MSU phagocytosis by macrophages. We used an antibody that sheds the extracellular domain (ECD) of CD44 to study the role of the receptor and its associated protein phosphatase 2A (PP2A) in macrophage activation. We also studied the significance of CD44 in mediating MSU inflammation in-vivo. Cd44^−/− BMDMs showed reduced MSU phagocytosis, LDH release, IL-1β expression and production compared to Cd44^+/+ BMDMs. Elevated CD44 staining was detected intracellularly and CD44 colocalized with α-tubulin as a result of MSU exposure and ECD-shedding reduced MSU phagocytosis in murine and human macrophages. Anti-CD44 antibody treatment reduced NF-κB p65 subunit nuclear levels, IL-1β expression, pro-IL-1β and IL-8 production in MSU stimulated THP-1 macrophages (p < 0.01). The effect of the antibody was mediated by an enhancement in PP2A activity. CD44 ECD-shedding reduced the conversion of procaspase-1 to active caspase-1, caspase-1 activity and resultant generation of mature IL-1β in macrophages. Neutrophil and monocyte influx and upregulated production of IL-1β was evident in wildtype mice. MSU failed to trigger neutrophil and monocyte recruitment in Cd44^−/− mice and lower IL-1β levels were detected in peritoneal lavages from Cd44^−/− mice (p < 0.01). Anti-CD44 antibody treatment reduced neutrophil and monocyte recruitment and resulted in reduced lavage IL-1β levels in the same model. CD44 plays a biologically significant role in mediating phagocytosis of MSU and downstream inflammation and is a novel target in gout treatment.

Design and Biological Evaluation of Colchicine-CD44-Targeted Peptide Conjugate in an In Vitro Model of Crystal Induced Inflammation

Gout is an inflammatory arthritis due to the joint deposition of monosodium urate (MSU) crystals. Phagocytosis of MSU crystals by tissue macrophages results in the generation of reactive oxygen species (ROS) and production of inflammatory cytokines and chemokines. Colchicine use in gout is limited by severe toxicity. CD44 is a transmembrane glycoprotein that is highly expressed in tissue macrophages and may be involved in gout pathogenesis. The P6 peptide is a 20-amino acid residue peptide that binds to CD44. We hypothesized that the conjugation of colchicine to the P6 peptide would reduce its off-target cytotoxicity while preserving its anti-inflammatory effect. A modified version of P6 peptide and colchicine-P6 peptide conjugate were synthesized using Fmoc/tBu solid-phase and solution-phase chemistry, respectively. A glutaryl amide was used as a linker. The P6 peptide was evaluated for its binding to CD44, association, and internalization by macrophages. Cytotoxic effects of P6 peptide, colchicine, and colchicine-P6 peptide on macrophages were compared and the inhibition of ROS generation and interleukin-8 (IL-8) secretion in MSU-stimulated macrophages treated with P6 peptide, colchicine, or colchicine-P6 peptide was studied. We confirmed that the P6 peptide binds to CD44 and its association and internalization by macrophages were CD44-dependent. Colchicine (1, 10, and 25 μM) demonstrated a significant cytotoxic effect on macrophages while the P6 peptide and colchicine-P6 peptide conjugate (1, 10 and 25 μM) did not alter the viability of the macrophages. The P6 peptide (10 and 25 μM) reduced ROS generation and IL-8 secretion mediated by a reduction in MSU phagocytosis by macrophages. The colchicine-P6 peptide significantly reduced ROS generation and IL-8 secretion compared to the P6 peptide alone at 1 and 10 μM concentrations. Conjugation of colchicine to the P6 peptide reduced the cytotoxic effect of colchicine while preserving its anti-inflammatory activity.

Educational inequalities in all-cause and cause-specific mortality among people with gout: a register-based matched cohort study in southern Sweden

Background

Gout is the most common inflammatory arthritis with a rising prevalence around the globe. While educational inequalities in incidence and prevalence of gout have been reported, no previous study investigated educational inequality in mortality among people with gout. The aim of this study was to assess absolute and relative educational inequalities in all-cause and cause-specific mortality among people with gout in comparison with an age- and sex-matched cohort free of gout in southern Sweden.

Methods

We identified all residents aged ≥30 years of Skåne region with doctor-diagnosed gout (ICD-10 code M10, n = 24,877) during 1998–2013 and up to 4 randomly selected age- and sex-matched comparators free of gout (reference cohort, n = 99,504). These were followed until death, emigration, or end of 2014. We used additive hazards models and Cox regression adjusted for age, sex, marital status, and country of birth to estimate slope and relative indices of inequality (SII/RII). Three cause-of-death attribution approaches were considered for RII estimation: “underlying cause”, “any mention”, and “weighted multiple-cause”.

Results

Gout patients with the lowest education had 1547 (95% CI: 1001, 2092) more deaths per 100,000 person-years compared with those with the highest education. These absolute inequalities were larger than in the reference population (1255, 95% CI: 1038, 1472). While the contribution of cardiovascular (cancer) mortality to these absolute inequalities was greater (smaller) in men with gout than those without, the opposite was seen among women. Relative inequality in all-cause mortality was smaller in gout (RII 1.29 [1.18, 1.41]) than in the reference population (1.46 [1.38, 1.53]). The weighted multiple-cause approach generally led to larger RIIs than the underlying cause approach.

Conclusions

Our register-based matched cohort study showed that low level of education was associated with increased mortality among gout patients. Although the magnitude of relative inequality was smaller in people with gout compared with those without, the absolute inequalities were greater reflecting a major mortality burden among those with lower education.

Gout

Gout is a chronic disease caused by monosodium urate (MSU) crystal deposition. Gout typically presents as an acute, self-limiting inflammatory monoarthritis that affects the joints of the lower limb. Elevated serum urate level (hyperuricaemia) is the major risk factor for MSU crystal deposition and development of gout. Although traditionally considered a disorder of purine metabolism, altered urate transport, both in the gut and the kidneys, has a key role in the pathogenesis of hyperuricaemia. Anti-inflammatory agents, such corticosteroids, NSAIDs and colchicine, are widely used for the treatment of gout flare; recognition of the importance of NLRP3 inflammasome activation and bioactive IL-1β release in initiation of the gout flare has led to the development of anti-IL-1β biological therapy for gout flares. Sustained reduction in serum urate levels using urate-lowering therapy is vital in the long-term management of gout, which aims to dissolve MSU crystals, suppress gout flares and resolve tophi. Allopurinol is the first-line urate-lowering therapy and should be started at a low dose, with gradual dose escalation. Low-dose anti-inflammatory therapies can reduce gout flares during initiation of urate-lowering therapy. Models of care, such as nurse-led strategies that focus on patient engagement and education, substantially improve clinical outcomes and now represent best practice for gout management.

Patterns of health care utilization of gout patients in Hawai'i-high rates of emergency department utilization as compared to rheumatoid arthritis

Recent and comprehensive research of gout in the Pacific region and Hawai'i is significantly lacking. This study was conducted to improve the understanding of the healthcare utilization of gout patients within a single health care system in Hawai'i. The objective was to examine gout inpatient, outpatient and emergency department care within a single health care system in Hawai'i. This study was a retrospective chart review of patients, ≥ 18 years admitted to three Hawai'i Pacific Health facilities for a primary diagnosis of gout or rheumatoid arthritis (RA) from 2011 to 2017. Population data for the State of Hawai'i was used to calculate visit rates per 1,000 Hawai'i adults. Trend analysis was performed to compare changes over time. We studied gout health care utilization concurrently with RA to provide an internal comparison group for the healthcare utilization patterns of interest. Gout patients were primarily managed in the outpatient setting with high rates of emergency department visits. In contrast, RA patients were primarily managed in the outpatient setting, with low rates of emergency department visits. Both gout and RA patients had low rates of inpatient admissions. The cost of gout emergency department visits was approximately 3.4 times higher than gout outpatient visits. The rates for gout emergency department visits, outpatient visits, inpatients visits, and RA outpatient visits in 2017 were trending downward and significantly changed from 2011 (p <0.05). The rates for RA emergency department visits and inpatient visits were not significantly changed from 2011-2017. Gout care in Hawai'i remains suboptimal with higher rates of emergency department visits, as compared to RA. Because emergency department visits are associated with higher cost, efforts should be made to reduce these emergency department visits to improve the quality of care.

Second-line treatment with lesinurad and allopurinol versus febuxostat for management of hyperuricemia: a cost-effectiveness analysis for Spanish patients

INTRODUCTION/OBJECTIVES

Lesinurad, in combination with allopurinol, has been approved for treatment of patients with gout which do not reach therapeutic serum urate target with xanthine oxidase inhibitors monotherapy. The study aimed to assess the incremental cost-effectiveness ratio of adding lesinurad to allopurinol as second-line therapy, compared to febuxostat for patients with gout in Spain.

METHOD

A Markov model representing disease evolution was used to estimate the lifetime accumulated cost and benefits in terms of quality-adjusted-life-year (QALY). Patients could either continue with second-line treatment with lesinurad (200 mg/daily) plus allopurinol (400 mg/daily) or febuxostat (80 mg/daily) switch to allopurinol monotherapy (271 mg/daily) in case of intolerance or discontinue treatment. The treatment's efficacy captured in the transition probabilities between health states were derived from CLEAR and EXCEL trials. Quality of life related to gout severity and flare frequency was considered by means of utilities. The total cost estimation (€, 2019) included drug acquisition cost, disease monitoring, and flare management cost. Unitary local costs derived from databases and literature. A 3% annual discount rate was applied for cost and outcomes.

RESULTS

Lesinurad plus allopurinol provided higher QALYs (14.79) than febuxostat (14.69). Total accrued cost/patient was lower with lesinurad and allopurinol (€50,631.51) versus febuxostat (€56,698.64). Lesinurad plus allopurinol resulted more effective and less costly (dominant option) versus febuxostat.

CONCLUSIONS

Lesinurad plus allopurinol therapy compared with febuxostat seems an effective option for the management of hyperuricemia in patients who did not reach serum urate target to previous allopurinol monotherapy, associated to cost-savings for the Spanish Health System.Key Points• Lesinurad, in combination with allopurinol, has been recently authorized as second-line treatment of hyperuricemia in gout patients.• Lesinurad plus allopurinol provided higher effectiveness in terms of quality-adjusted-life-years (14.79) than febuxostat (14.69).• Lesinurad plus allopurinol resulted less costly (total cost/per patient) compared with febuxostat.• Lesinurad plus allopurinol resulted a dominant option compared with febuxostat.

Paeonol ameliorates monosodium urate-induced arthritis in rats through inhibiting nuclear factor-κB-mediated proinflammatory cytokine production

Moutan Cortex has been widely used to treat various types of arthritis in traditional Chinese medicine. Paeonol is isolated as an active ingredient from Moutan Cortex. However, the effect and potential mechanism of paeonol on gouty arthritis have not been evaluated. In this study, rats were treated intragastrically with paeonol for consecutive 7 days. On Day 5, rats were intra-articularly injected with monosodium urate (MSU) crystals in the ankle joints to induce MSU-induced arthritis (MIA). Paw volume was detected at various time points. Gait score was measured at 24 hr after MSU crystal injection. Ankle joints were collected for evaluation of histological score and expression of proinflammatory cytokines using hematoxylin and eosin staining and immunohistochemistry staining, respectively. Nuclear level of nuclear factor (NF)-κBp65 in synovial tissues was analyzed by western blot assay. NF-κB DNA-binding activity was measured by enzyme linked immunosorbent assay. Paeonol markedly lowered the paw volume, gait score, and histological score in MIA rats. Mechanistically, paeonol markedly reduced the expression of TNF-α, IL-1β, and IL-6 in synovial tissues of MIA rats. In addition, the elevated level of p65 in nucleus and NF-κB DNA-binding activity in synovial tissues of MIA rats were reduced significantly by paeonol treatment. These findings suggest that paeonol exerts anti-inflammatory effect in MIA rats through inhibiting expression of proinflammatory cytokines and NF-κB activation.

Effectiveness of healthcare educational and behavioral interventions to improve gout outcomes: a systematic review and meta-analysis

BACKGROUND

We aimed to systematically review the effectiveness of healthcare behavioral and education interventions for gout patients on clinical outcomes.

METHODS

We searched multiple databases to identify trials or observational studies of educational or behavioral interventions in gout. Risk of bias was assessed with the Cochrane tool for randomized control trials (RCTs) and the Newcastle-Ottawa Scale for observational studies. We estimated odds ratios (ORs) for categorical and standardized mean difference (SMD) for continuous measures using a random-effects model.

RESULTS

Overall, eight (five RCTs and three observational) studies met the inclusion criteria and examined pharmacist-led interventions (n = 3), nurse-led interventions (n = 3) and primary care provider interventions (n = 2). Compared with the control intervention (usual care in most cases), a higher proportion of those in the educational/behavioral intervention arm achieved serum urate (SU) levels <6 mg/dl, 47.2% versus 23.8%, the OR was 4.86 [95% confidence interval (CI), 1.48, 15.97; 4 RCTs] with moderate quality evidence. Compared with the control intervention, a higher proportion of those in the educational/behavioral intervention arm were adherent to allopurinol, achieved at least a 2 mg/dl decrease in SU, achieved an SU < 5 mg/dl, had a reduction in the presence of tophi at 2 years, had improved quality of life as assessed with SF-36 physical component scores, had a higher knowledge about gout and higher patient satisfaction (moderate-low quality evidence).

CONCLUSION

Educational and behavioral interventions can improve gout outcomes in the short-intermediate term. Randomized trials are needed to assess its impact on long-term gout outcomes.

Hospitalization Increases the Risk of Acute Arthritic Flares in Gout: A Population-based Study over 2 Decades

OBJECTIVE

To assess in-hospital gout flares in patients with gout.

METHODS

Hospitalizations were evaluated for gout flares in a cohort of Olmsted County, Minnesota, residents with incident gout in 1989-1992 or 2009-2010.

RESULTS

There were 429 patients followed up to 5 years. Of these, 169 patients experienced 454 hospitalizations. Hospitalization rates increased without reaching statistical significance from 1989-1992 to 2009-2010 [rate ratio (RR) 1.19, 95% CI 0.98-1.45]. The gout flare rate increased significantly during hospitalization (RR 10.2, 95% CI 6.8-14.5). In-hospital gout flare increased the average hospital stay by 1.8 days (p < 0.001).

CONCLUSION

Hospitalization increased the risk of gout flares 10-fold. In-hospital gout flares were associated with longer hospitalization.

A Beacon in the Dark: Canakinumab. A New Therapeutic Perspective in Chronic Tophaceous Gout

Gout is the most common form of arthritis in adults. It is often associated with other comorbidities, which contraindicate the use of conventional therapies. The discovery of the role of interleukin-1β (IL-1β) in orchestrating the monosodium urate crystal-induced inflammatory response offered new therapeutic prospects to refractory patients, or to those in whom standard therapies are contraindicated. This paper describes a clinical case of a 65-year-old man with chronic tophaceous gouty arthropathy and subintrant flares, who had comorbidities contraindicating the use of conventional gout therapies-to which he did not respond-who was treated with canakinumab, a monoclonal selective inhibitor of IL-1β. The patient reported a gradual, rapid, and significant reduction in pain, with a response observed within 12 h of the administration of the drug. Consistent with previous clinical studies, canakinumab appeared to be a viable, safe, and effective alternative to conventional therapies in this patient with gout who had limited therapeutic options.

FUNDING

Novartis Farma, Italy.

A Beacon in the Dark: Canakinumab. A New Therapeutic Perspective in Chronic Tophaceous Gout

Gout is the most common form of arthritis in adults. It is often associated with other comorbidities, which contraindicate the use of conventional therapies. The discovery of the role of interleukin-1β (IL-1β) in orchestrating the monosodium urate crystal-induced inflammatory response offered new therapeutic prospects to refractory patients, or to those in whom standard therapies are contraindicated. This paper describes a clinical case of a 65-year-old man with chronic tophaceous gouty arthropathy and subintrant flares, who had comorbidities contraindicating the use of conventional gout therapies-to which he did not respond-who was treated with canakinumab, a monoclonal selective inhibitor of IL-1β. The patient reported a gradual, rapid, and significant reduction in pain, with a response observed within 12 h of the administration of the drug. Consistent with previous clinical studies, canakinumab appeared to be a viable, safe, and effective alternative to conventional therapies in this patient with gout who had limited therapeutic options.

FUNDING

Novartis Farma, Italy.

Association of gout and depression: A systematic review and meta-analysis

OBJECTIVE

Several studies have shown that gout is associated with depression symptoms. In this study, a systematic review and meta-analysis was performed to explore the relationship between gout and depression.

METHODS

Published articles were identified through a comprehensive review of PUBMED and EMBASE. Data from studies reporting relative risks, odds ratios, or hazard ratios comparing the risk of depression among participants who had gout versus those without gout were analyzed. A random-effect model was used to calculate pooled odds ratios and 95% confident intervals (CI).

RESULTS

Seven studies, which included 411 745 participants, aligned with our inclusion criteria and were included in the meta-analysis. Pooled analysis showed an association between gout and depression, with an odds ratio of 1.19 (95%CI, 1.11, 1.29; I²  = 60.2%). Subgroup-analysis adjusted (or not) by study type or study quality showed a statistically significant association of gout and depression in all subgroups. Sensitivity analysis by 1-study removed analysis, excluding articles of self-reported gout assessment or male-only, confirmed the robustness of our results.

CONCLUSION

Our meta-analysis demonstrates a positive association between gout and depression. Further large-scale prospective cohort studies are needed to investigate the causality between gout and depression.

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.

Dietary Potential Renal Acid Load Is Positively Associated with Serum Uric Acid and Odds of Hyperuricemia in the German Adult Population

Background

Initial interventional data indicate that a reduction in dietary acid load (e.g., by an increased consumption of alkalizing fruit and vegetables) can increase renal uric acid excretion and decrease serum uric acid (SUA).

Objective

Against this background, we examined the association between dietary potential renal acid load (PRAL) and SUA in a representative population sample.

Methods

Cross-sectional analyses were performed in 6894 participants (aged 18-79 y) of the German Health Interview and Examination Survey for Adults (DEGS1). Dietary intake was assessed with a food-frequency questionnaire. Nutritive acid load and the intake of uric acid equivalents (UAEs) were characterized by assigning PRAL and UAE values to reported food consumption. In multiple linear regression models, the associations of PRAL, UAEs, and relevant food groups with SUA were analyzed. Multiple logistic regressions were used to calculate ORs for hyperuricemia comparing lower and upper tertiles of the predictors.

Results

After adjustment for relevant confounders, PRAL (P = 0.003), alcohol (P < 0.0001), and UAE (P = 0.03) intakes were positively associated with SUA, whereas the intake of dairy products and fruit and vegetables was inversely associated (both P < 0.0001). Subgroup analyses among participants without interacting medication use confirmed these results. In addition, participants with lower PRAL had lower odds for hyperuricemia (OR: 0.60; 95% CI: 0.43, 0.83).

Conclusions

Apart from observing known dietary influences on SUA, we found in this population-based, cross-sectional study in adults that low PRAL may represent a potentially SUA-reducing dietary pattern. This highlights dietary alkalization as a possible nonpharmacologic option to influence elevated SUA concentrations.

Gout Classification Criteria: Update and Implications

Gout is the most common inflammatory arthritis, with a rising prevalence and incidence worldwide. There has been a resurgence in gout research, fueled, in part, by a number of advances in pharmacologic therapy for gout. The conduct of clinical trials and other observational research in gout requires a standardized and validated means of assembling well-defined groups of patients with gout for such research purposes. Recently, an international collaborative effort that involved a data-driven process with state-of-the art methodology supported by the American College of Rheumatology and the European League Against Rheumatism led to publication of new gout classification criteria.

Treat-to-target (T2T) recommendations for gout

OBJECTIVES

The treat-to-target (T2T) concept has been applied successfully in several inflammatory rheumatic diseases. Gout is a chronic disease with a high burden of pain and inflammation. Because the pathogenesis of gout is strongly related to serum urate levels, gout may be an ideal disease in which to apply a T2T approach. Our aim was to develop international T2T recommendations for patients with gout.

METHODS

A committee of experts with experience in gout agreed upon potential targets and outcomes, which was the basis for the systematic literature search. Eleven rheumatologists, one cardiologist, one nephrologist, one general practitioner and one patient met in October 2015 to develop T2T recommendations based on the available scientific evidence. Levels of evidence, strength of recommendations and levels of agreement were derived.

RESULTS

Although no randomised trial was identified in which a comparison with standard treatment or an evaluation of a T2T approach had been performed in patients with gout, indirect evidence was provided to focus on targets such as normalisation of serum urate levels. The expert group developed four overarching principles and nine T2T recommendations. They considered dissolution of crystals and prevention of flares to be fundamental; patient education, ensuring adherence to medications and monitoring of serum urate levels were also considered to be of major importance.

CONCLUSIONS

This is the first application of the T2T approach developed for gout. Since no publication reports a trial comparing treatment strategies for gout, highly credible overarching principles and level D expert recommendations were created and agreed upon.

Alcohol Use and Activity Limitations in Gout Patients

BACKGROUND

Few studies have evaluated whether patients with a diagnosis of gout adhere to alcohol use recommendations and the relationship between adherence and activity limitations.

PURPOSE

The purpose of this study was to determine adherence to American College of Rheumatology (ACR) alcohol use recommendations and evaluate the relationship between alcohol use and activity limitations in persons with gout.

METHOD

A secondary analysis was performed with a sample of 298 persons with gout from the 2008 National Health Interview Survey.

RESULTS

In all, 22.8% of persons with gout were nonadherent to alcohol use recommendations. Males, those aged 41-60 years, and those not receiving healthcare for joint symptoms were most likely to be nonadherent. In all, 39.9% reported that joint symptoms interfered with activity in the preceding 30 days. Those who were adherent were more likely to report limitations (χ = 6.788, p = .03).

CONCLUSIONS

To promote optimal patient outcomes, more attention needs to be devoted to individualized patient education and self-management interventions that follow ACR recommendations.

Lesinurad, a novel, oral compound for gout, acts to decrease serum uric acid through inhibition of urate transporters in the kidney

Background

Excess body burden of uric acid promotes gout. Diminished renal clearance of uric acid causes hyperuricemia in most patients with gout, and the renal urate transporter (URAT)1 is important for regulation of serum uric acid (sUA) levels. The URAT1 inhibitors probenecid and benzbromarone are used as gout therapies; however, their use is limited by drug–drug interactions and off-target toxicity, respectively. Here, we define the mechanism of action of lesinurad (Zurampic®; RDEA594), a novel URAT1 inhibitor, recently approved in the USA and Europe for treatment of chronic gout.

Methods

sUA levels, fractional excretion of uric acid (FE_UA), lesinurad plasma levels, and urinary excretion of lesinurad were measured in healthy volunteers treated with lesinurad. In addition, lesinurad, probenecid, and benzbromarone were compared in vitro for effects on urate transporters and the organic anion transporters (OAT)1 and OAT3, changes in mitochondrial membrane potential, and human peroxisome proliferator-activated receptor gamma (PPARγ) activity.

Results

After 6 hours, a single 200-mg dose of lesinurad elevated FE_UA 3.6-fold (p < 0.001) and reduced sUA levels by 33 % (p < 0.001). At concentrations achieved in the clinic, lesinurad inhibited activity of URAT1 and OAT4 in vitro, did not inhibit GLUT9, and had no effect on ABCG2. Lesinurad also showed a low risk for mitochondrial toxicity and PPARγ induction compared to benzbromarone. Unlike probenecid, lesinurad did not inhibit OAT1 or OAT3 in the clinical setting.

Conclusion

The pharmacodynamic effects and in vitro activity of lesinurad are consistent with inhibition of URAT1 and OAT4, major apical transporters for uric acid. Lesinurad also has a favorable selectivity and safety profile, consistent with an important role in sUA-lowering therapy for patients with gout.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1107-x) contains supplementary material, which is available to authorized users.

Epidemiology of inpatient gout in Australia and New Zealand: temporal trends, comorbidities and gout flare site

AIM

To assess the epidemiology of inpatient gout in Australia and New Zealand during the years 2009-2014.

METHODS

Using the Health Roundtable Limited (HRT) dataset, all patients with a coded ICD10 primary or secondary discharge diagnosis of gout from a HRT participating Australian or New Zealand hospital between the years 2009 and 2014 were identified. The number of inpatient gout admissions, length of stay, body site of gout flare, temporal trends and comorbidities were assessed.

RESULTS

During 2009-2014, the number of gout admissions increased significantly in Australia and New Zealand. The rate of inpatient gout admissions relative to the population and total HRT admissions rose in Australia and stayed static in New Zealand. Lower limb presentations were the commonest anatomical site of gout in admitted patients. Length of stay over the course of the study decreased both in patients admitted for gout and in those in the entire HRT dataset. Patients admitted for gout have longer length of stay compared to patients admitted for other reasons. Cardiovascular disease, infection and stroke were the commonest conditions that were complicated by an episode of inpatient gout. There was no influence of month or season on the pattern of gout admissions.

CONCLUSION

The number of gout admissions rose in Australia numerically and as a proportion of the total population and total admissions. Gout is an increasing problem affecting individuals and the community as a whole in Australia.

Pharmacokinetics, pharmacodynamics, and tolerability of LC350189, a novel xanthine oxidase inhibitor, in healthy subjects

Introduction

LC350189 is a novel selective xanthine oxidase inhibitor under clinical development for the management of hyperuricemia in gout patients. The aim of this study was to evaluate the pharmacokinetics, pharmacodynamics, and tolerability of the drug in healthy subjects.

Methods

A dose-block randomized, double-blind, active and placebo-controlled, single- and multiple-dosing study was conducted. A single ascending dose (SAD) study (10–600 mg) and a multiple ascending dose (MAD) study with once-daily doses (100–800 mg) for 7 days were conducted. Serial samples of blood and urine for pharmacokinetics/pharmacodynamics analysis were collected, and tolerability and adverse events were assessed throughout the study.

Results

Sixty-seven and 58 subjects were enrolled in the SAD and MAD studies, respectively. The mean C_max and AUC_last values increased with increasing doses, and exposure to LC350189 was dose proportional. The 24-hour mean serum uric acid (C_mean,24) decreased by 8.7%–31.7% (day 1) and 53.5%–91.2% (day 7) from baseline in the SAD and MAD studies, respectively, and the percentage decrease in C_mean,24 increased with higher doses.

Conclusion

LC350189 was well tolerated in the dose range of 10–800 mg. It lowered the serum and urine uric acid levels substantially in this dose range; the extent of the decrease in the serum uric acid level in the 200 mg dose group was similar or higher compared to that of febuxostat 80 mg group in the MAD study. It is expected that LC350189 could be safely administered once daily to patients with hyperuricemia or gout, leading to a sufficient decrease in uric acid levels.