Gender and Ethnic Inequities in Gout Burden and Management

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.

Unclosing Premature Mortality Gap Among Patients With Gout in the US General Population, Independent of Serum Urate and Atherosclerotic Cardiovascular Risk Factors

OBJECTIVE

Gout flares are followed by transient major cardiovascular (CV) risk, implicating the role of inflammation; the aim of this study was to determine whether premature mortality rates in patients with gout and CV risk are independent of serum urate (SU) and atherosclerotic CV disease (ASCVD) risk factors.

METHODS

Using serial US nationwide prospective cohorts, we evaluated the independent association of prevalent gout with all-cause and CV mortality, adjusting for SU, ASCVD risk factors, comorbidities, medications, and kidney function and compared mortality rates between the early (1988-1994 baseline) and late cohorts (2007-2016 baseline). We replicated late cohort findings among patients with gout in a nationwide UK cohort (2006-2010 baseline).

RESULTS

Adjusted hazard ratios (HRs) for mortality rates in patients with prevalent gout were similar in early and late US cohorts (1.20 [1.03-1.40] and 1.19 [1.04-1.37], respectively); HRs with further adjustment for SU were 1.19 (1.02-1.38) and 1.19 (1.03-1.37), respectively. Adjusted HR among patients with gout from the UK late cohort was 1.61 (1.47-1.75); these associations were larger among women (P = 0.04) and prominent among Black individuals. Adjusted HR for CV mortality rates in the late US cohort was 1.39 (1.09-1.78); those for circulatory, CV, and coronary heart disease deaths among UK patients with incident gout were 1.48 (1.24-1.76), 1.49 (1.20-1.85), and 1.59 (1.26-1.99), respectively.

CONCLUSIONS

Patients with gout experience a persistent mortality gap in all-cause and CV deaths, even adjusting for SU and ASCVD risk factors, supporting a role for gout-specific pathways (eg, flare inflammation). These findings suggest gaps in current care, particularly in women and possibly among Black patients.

Perspectives of Nephrologists on Gender Disparities in Access to Kidney Transplantation

BACKGROUND

Gender disparities in access to kidney transplantation are apparent, with women being up to 20% less likely to receive kidney transplant compared with men across different settings and socioeconomic backgrounds. We aimed to describe nephrologists' perspectives on gender disparities in access to kidney transplantation.

METHODS

Fifty-one nephrologists (55% women) from 22 countries participated in semistructured interviews from October 2019 to April 2020. We analyzed the transcripts thematically.

RESULTS

We identified three themes: caregiving as a core role (coordinators of care for partners, fulfilling family duties over own health, maternal protectiveness, and inherent willingness and generosity), stereotyping and stigma (authority held by men in decision making, protecting the breadwinner, preserving body image and appearance, and safeguard fertility), social disadvantage and vulnerability (limited information and awareness, coping alone and lack of support, disempowered by language barriers, lack of financial resources, and without access to transport).

CONCLUSIONS

Gender disparities in access to kidney transplantation are perceived by nephrologists to be exacerbated by gender norms and values, stigma and prejudice, and educational and financial disadvantages that are largely encountered by women compared with men across different socioeconomic settings.

Filling gaps in female gout: a cross-sectional study of comorbidities in 192 037 hospitalised patients

OBJECTIVE

There is room for improvement in the knowledge of female gout, often noted at risk of gender blindness. This study aims to compare the prevalence of comorbidities in women versus men hospitalised with gout in Spain.

METHODS

This is an observational, multicentre, cross-sectional study in public and private Spanish hospitals analysing the minimum basic data set from 192 037 hospitalisations in people with gout (International Classification of Diseases, Ninth Revision (ICD-9) coding) from 2005 to 2015. Age and several comorbidities (ICD-9) were compared by sex, with a subsequent stratification of comorbidities by age group. The association between each comorbidity and sex was assessed using multivariable logistic regression. A clinical decision tree algorithm was constructed to predict the sex of patients with gout based on age and comorbidities alone.

RESULTS

Women with gout (17.4% of the sample) were significantly older than men (73.9±13.7 years vs 64.0±14.4 years, p<0.001). Obesity, dyslipidaemia, chronic kidney disease, diabetes mellitus, heart failure, dementia, urinary tract infection and concurrent rheumatic disease were more common in women. Female sex was strongly associated with increasing age, heart failure, obesity, urinary tract infection and diabetes mellitus, while male sex was associated with obstructive respiratory diseases, coronary disease and peripheral vascular disease. The decision tree algorithm built showed an accuracy of 74.4%.

CONCLUSIONS

A nationwide analysis of inpatients with gout in 2005-2015 confirms a different comorbidity profile between men and women. A different approach to female gout is needed to reduce gender blindness.

Nationwide racial/ethnic disparities in US emergency department visits and hospitalizations for gout

OBJECTIVES

Gout prevalence is reportedly ∼20% higher in US Black adults than Whites, but racial differences in emergency department (ED) visits and hospitalizations for gout are unknown. We evaluated the latest US national utilization datasets according to racial/ethnic groups.

METHODS

Using 2019 US National Emergency Department Sample and National Inpatient Sample databases, we compared racial/ethnic differences in annual population rates of ED visits and hospitalizations for gout (primary discharge diagnosis) per 100 000 US adults (using 2019 age- and sex-specific US census data). We also examined rates of ED visits and hospitalizations for gout among all US ED visits/hospitalizations and mean costs for each gout encounter.

RESULTS

Compared with White patients, the per capita age- and sex-adjusted rate ratio (RR) of gout primary ED visits for Black patients was 5.01 (95% CI 4.96, 5.06), for Asian patients 1.29 (1.26, 1.31) and for Hispanic patients 1.12 (1.10, 1.13). RRs for gout primary hospitalizations were 4.07 (95% CI 3.90, 4.24), 1.46 (1.34, 1.58) and 1.06 (0.99, 1.13), respectively. Corresponding RRs among total US hospitalizations were 3.17 (95% CI 2.86, 3.50), 3.23 (2.71, 3.85) and 1.43 (1.21, 1.68) and among total ED visits were 2.66 (95% CI, 2.50, 2.82), 3.28 (2.64, 4.08), and 1.14 (1.05, 1.24), respectively. RRs were largest among Black women. Costs for ED visits and hospitalizations experienced by race/ethnicity showed similar disparities.

CONCLUSIONS

These first nationwide data found a substantial excess in both gout primary ED visits and hospitalizations experienced by all underserved racial/ethnic groups, particularly by Black women, revealing an urgent need for improved care to eliminate inequities in gout outcomes.

Trends in Prevalence of Gout Among US Asian Adults, 2011-2018

Importance

Gout disparities among Black individuals in the US have recently been explained by socioclinical factors; however, no information is available among Asian individuals living in Western countries, despite their disproportionately worsening metabolic health.

Objective

To determine the prevalence of gout and serum urate concentrations according to race and ethnicity and to explore the association of social determinants of health and clinical factors.

Design, Setting, and Participants

This is a population-based, cross-sectional analysis. Data from a nationally representative sample of US adults were obtained from the National Health and Nutrition Examination Survey (NHANES) (2011-2018) in which Asian race data were collected (primary). Data from the UK Biobank (2006-2021) were used for replication of the Asian vs White differences. Data analysis was performed from December 2021 to September 2022.

Main Outcomes and Measures

Race-specific gout prevalence and serum urate levels.

Results

A total of 22 621 participants from NHANES (2011-2018) were included in the analysis (mean [SD] age, 49.8 [17.8] years; 10 948 male participants [48.4%]). In 2017 to 2018, gout affected 12.1 million US individuals, with its crude prevalence increasing from 3.6% (95% CI, 2.8%-4.5%) in 2011 to 2012 to 5.1% (95% CI, 4.2%-5.9%) in 2017 to 2018 (P for trend = .03); this trend was no longer significant after age adjustment (P for trend = .06) or excluding Asian individuals (P for trend = .11). During the same period, age- and sex-adjusted prevalence among Asian Americans doubled from 3.3% (95% CI, 2.1%-4.5%) to 6.6% (95% CI, 4.4%-8.8%) (P for trend = .007) to numerically exceed all other racial and ethnic groups in 2017 to 2018, with age- and sex-adjusted odds ratio (ORs) of 1.61 (95% CI, 1.03-2.51) and a socioclinical factor-adjusted multivariable OR of 2.62 (95% CI, 1.59-4.33) for Asian vs White individuals. The latest age- and sex-adjusted gout prevalence among US individuals aged 65 years and older was 10.0% among White individuals and 14.8% among Asian individuals (including 23.6% of Asian men). Serum urate concentrations also increased between 2011 and 2018 among US Asian individuals (P for trend = .009). The Asian vs White disparity was also present in the UK Biobank.

Conclusions and Relevance

The findings of this study suggest that the prevalence of gout among Asian individuals numerically surpassed that for all other racial and ethnic groups in 2017 to 2018. This Asian vs White disparity did not appear to be associated with socioclinical factors.

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

Moving the Needle in Gout Management: The Role of Culture, Diet, Genetics, and Personalized Patient Care Practices

Gout is a metabolic disorder, and one of the most common inflammatory arthritic conditions, caused by elevated serum urate (SU). Gout is globally rising, partly due to global dietary changes and the growing older adult population. Gout was known to affect people of high socioeconomic status. Currently, gout disproportionately affects specific population subgroups that share distinct racial and ethnic backgrounds. While genetics may predict SU levels, nongenetic factors, including diet, cultural traditions, and social determinants of health (SDOH), need to be evaluated to optimize patient treatment outcomes. This approach would allow clinicians to assess whether certain cultural norms, or some SDOH, could be contributing to their patient’s risk of developing gout or recurrent gout flares. A cultural assessment may inform the development of culturally tailored dietary recommendations for patients with gout. Causal and association studies investigating the interaction between diet, genetics, and gout, should be cautiously interpreted due to the lack of reproducibility in different racial groups. Optimal gout management could benefit from a multidisciplinary approach, involving pharmacists and nurses. While data on the effect of specific dietary recommendations on managing hyperuricemia and gout may be limited, counseling patients with gout on the role of a healthy diet to optimally control their gout flares and other comorbidities should be part of patient education. Future research investigating the role of a gene–diet interaction in the context of hyperuricemia and gout is needed. Optimal care for patients with gout needs to include a holistic assessment for gout and gout-related comorbidities. Additionally, addressing health beliefs and culture-specific lifestyle factors among patients with gout may reduce their risk of gout flare, improve adherence to urate-lowering therapy (ULT), and achieve health equity in gout management.

A glance into the future of gout

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

A Polynesian-specific copy number variant encompassing the MHC Class I Polypeptide-related Sequence A (MICA) gene associates with gout

Gout is of particularly high prevalence in the Māori and Pacific (Polynesian) populations of Aotearoa New Zealand (NZ). Here, we investigated the contribution of common population-specific copy number variation (CNV) to gout in the Aotearoa NZ Polynesian population. Microarray-generated genome-wide genotype data from Aotearoa NZ Polynesian individuals with (n = 1196) and without (n = 1249) gout were analyzed. Comparator population groups were 552 individuals of European ancestry and 1962 of Han Chinese ancestry. Levels of circulating major histocompatibility complex (MHC) class I polypeptide-related sequence A (MICA) were measured by enzyme-linked immunosorbent assay. Fifty-four CNV regions (CNVRs) appearing in at least 10 individuals were detected, of which seven common (>2%) CNVRs were specific to or amplified in Polynesian people. A burden test of these seven revealed associations of insertion/deletion with gout (odds ratio (OR) 95% confidence interval [CI] = 1.80 [1.01; 3.22], P = 0.046). Individually testing of the seven CNVRs for association with gout revealed nominal association of CNVR1 with gout in Western Polynesian (Chr6: 31.36–31.45 Mb, OR = 1.72 [1.03; 2.92], P = 0.04), CNVR6 in the meta-analyzed Polynesian sample sets (Chr1: 196.75–196.92 Mb, OR = 1.86 [1.16; 3.00], P = 0.01) and CNVR9 in Western Polynesian (Chr1: 189.35–189.54 Mb, OR = 2.75 [1.15; 7.13], P = 0.03). Analysis of European gout genetic association data demonstrated a signal of association at the CNVR1 locus that was an expression quantitative trait locus for MICA. The most common CNVR (CNVR1) includes deletion of the MICA gene, encoding an immunomodulatory protein. Expression of MICA was reduced in the serum of individuals with the deletion. In summary, we provide evidence for the association of CNVR1 containing MICA with gout in Polynesian people, implicating class I MHC-mediated antigen presentation in gout.

Adherence to 2020 to 2025 Dietary Guidelines for Americans and the Risk of New-Onset Female Gout

IMPORTANCE

Female-specific gout data are scarce despite perceived differences from males in its risk factors and disproportionate worsening in disease and comorbidity burden globally. The 2020 to 2025 Dietary Guidelines for Americans recommend multiple healthy eating patterns for prevention of cardiovascular-metabolic outcomes, which may also be relevant to the prevention of female gout.

OBJECTIVE

To examine the associations of dietary scores for the latest guideline-based healthy eating patterns with risk of incident female gout.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included 80 039 US women in the Nurses' Health Study followed up through questionnaires every 2 years starting from 1984. Participants had no history of gout at baseline, and the study used questionnaire responses through 2018. Statistical analyses were performed over September 2020 to August 2021.

EXPOSURES

Four healthy eating patterns: Dietary Approaches to Stop Hypertension (DASH), Alternate Mediterranean Diet Score, Alternative Healthy Eating Index (AHEI), and Prudent, plus Western (unhealthy) for comparison, with scores derived from validated food frequency questionnaires.

MAIN OUTCOMES AND MEASURES

Incident, physician-diagnosed female-specific gout.

RESULTS

During 34 years of follow-up, we documented 3890 cases of incident female gout. Compared with the least-adherent quintile, women most adherent to healthy diets had significantly lower risk of incident gout, with multivariable-adjusted hazard ratios (HRs) 0.68 (95% CI, 0.61-0.76) (DASH), 0.88 (95% CI, 0.80-0.98) (Mediterranean), 0.79 (95% CI, 0.71-0.89) (AHEI), and 0.75 (95% CI, 0.73-0.90) (Prudent); all P for trend ≤.009. Conversely, women with highest-quintile Western diet score had 49% higher risk of gout (HR, 1.49; 95% CI, 1.33-1.68], P <.001). When combined, the most DASH-diet adherent women with normal body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) had a 68% lower risk of gout compared with the least adherent women with overweight or obese BMI; the corresponding risk reduction was 65% combining high DASH diet adherence with no diuretic use.

CONCLUSIONS AND RELEVANCE

These large-scale, long-term prospective cohort findings extend the pleotropic benefits of the 2020 to 2025 Dietary Guidelines for Americans to female gout prevention, with multiple healthy diets that can be adapted to individual food traditions, preferences, and comorbidities.

Oxygen-Ozone Therapy for Reducing Pro-Inflammatory Cytokines Serum Levels in Musculoskeletal and Temporomandibular Disorders: A Comprehensive Review

To date, the application of oxygen-ozone (O₂O₃) therapy has significantly increased in the common clinical practice in several pathological conditions. However, beyond the favorable clinical effects, the biochemical effects of O₂O₃ are still far from being understood. This comprehensive review aimed at investigating the state of the art about the effects of O₂O₃ therapy on pro-inflammatory cytokines serum levels as a modulator of oxidative stress in patients with musculoskeletal and temporomandibular disorders (TMD). The efficacy of O₂O₃ therapy could be related to the moderate oxidative stress modulation produced by the interaction of ozone with biological components. More in detail, O₂O₃ therapy is widely used as an adjuvant therapeutic option in several pathological conditions characterized by chronic inflammatory processes and immune overactivation. In this context, most musculoskeletal and temporomandibular disorders (TMD) share these two pathophysiological processes. Despite the paucity of in vivo studies, this comprehensive review suggests that O₂O₃ therapy might reduce serum levels of interleukin 6 in patients with TMD, low back pain, knee osteoarthritis and rheumatic diseases with a concrete and measurable interaction with the inflammatory pathway. However, to date, further studies are needed to clarify the effects of this promising therapy on inflammatory mediators and their clinical implications.

Intensive serum urate lowering with oral urate-lowering therapy for erosive gout: A randomized double-blind controlled trial

OBJECTIVE

To determine whether intensive serum urate lowering results in improved bone erosion scores in erosive gout.

METHODS

Two-year, double-blind, randomized, controlled trial of 104 participants with erosive gout on oral urate-lowering therapy (ULT) and serum urate ≥ 0.30mmol/L was undertaken. Participants were randomly assigned to serum urate target <0.20mmol/L (intensive target) or <0.30mmol/L (standard target, according to rheumatology guidelines). Oral ULT was titrated to target using a standardized protocol (using maximum approved doses of allopurinol, probenecid, febuxostat, and benzbromarone). The primary endpoint was total CT erosion score. OMERACT gout core outcome domains were secondary endpoints.

RESULTS

Although the serum urate was significantly lower in the intensive target group compared to the standard target group (P=0.002), fewer participants in the intensive group achieved the randomized serum urate target (at Year 2, 62% vs 83%, P<0.05). The intensive target group required higher allopurinol doses (mean (SD) 746 (210) mg/day vs 496 (185) mg/day, P<0.001), and used more combination therapy (P=0.0004). Small increases in CT erosion scores were observed in both groups over two years, with no between-group difference (P=0.20). OMERACT core outcome domains (gout flares, tophus, pain, patient global assessment, health-related quality of life, and activity limitation) improved in both groups, with no between-group differences. Adverse event and serious adverse event rates were similar between groups.

CONCLUSION

Compared with a serum urate target below 0.30mmol/L, more intensive serum urate-lowering is difficult to achieve with oral ULT, leads to high medication burden, and does not improve bone erosion scores in erosive gout.

Mid-pass whole genome sequencing enables biomedical genetic studies of diverse populations

BACKGROUND

Historically, geneticists have relied on genotyping arrays and imputation to study human genetic variation. However, an underrepresentation of diverse populations has resulted in arrays that poorly capture global genetic variation, and a lack of reference panels. This has contributed to deepening global health disparities. Whole genome sequencing (WGS) better captures genetic variation but remains prohibitively expensive. Thus, we explored WGS at "mid-pass" 1-7x coverage.

RESULTS

Here, we developed and benchmarked methods for mid-pass sequencing. When applied to a population without an existing genomic reference panel, 4x mid-pass performed consistently well across ethnicities, with high recall (98%) and precision (97.5%).

CONCLUSION

Compared to array data imputed into 1000 Genomes, mid-pass performed better across all metrics and identified novel population-specific variants with potential disease relevance. We hope our work will reduce financial barriers for geneticists from underrepresented populations to characterize their genomes prior to biomedical genetic applications.

Where Epigenetics Meets Food Intake: Their Interaction in the Development/Severity of Gout and Therapeutic Perspectives

Gout is the most frequent form of inflammatory arthritis in the world. Its prevalence is particularly elevated in specific geographical areas such as in the Oceania/Pacific region and is rising in the US, Europe, and Asia. Gout is a severe and painful disease, in which co-morbidities are responsible for a significant reduction in life expectancy. However, gout patients remain ostracized because the disease is still considered "self-inflicted", as a result of unhealthy lifestyle and excessive food and alcohol intake. While the etiology of gout flares is clearly associated with the presence of monosodium urate (MSU) crystal deposits, several major questions remain unanswered, such as the relationships between diet, hyperuricemia and gout flares or the mechanisms by which urate induces inflammation. Recent advances have identified gene variants associated with gout incidence. Nevertheless, genetic origins of gout combined to diet-related possible uric acid overproduction account for the symptoms in only a minor portion of patients. Hence, additional factors must be at play. Here, we review the impact of epigenetic mechanisms in which nutrients (such as ω-3 polyunsaturated fatty acids) and/or dietary-derived metabolites (like urate) trigger anti/pro-inflammatory responses that may participate in gout pathogenesis and severity. We propose that simple dietary regimens may be beneficial to complement therapeutic management or contribute to the prevention of flares in gout patients.

Aotearoa New Zealand Māori and Pacific Population-amplified Gout Risk Variants: CLNK Is a Separate Risk Gene at the SLC2A9 Locus

OBJECTIVE

The Māori and Pacific (Polynesian) population of Aotearoa New Zealand has a high prevalence of gout. Our aim was to identify potentially functional missense genetic variants in candidate inflammatory genes amplified in frequency that may underlie the increased prevalence of gout in Polynesian populations.

METHODS

A list of 712 inflammatory disease-related genes was generated. An in silico targeted exome set was extracted from whole genome sequencing data in people with gout of various ancestral groups (Polynesian, European, East Asian; n = 55, 780, 135, respectively) to identify Polynesian-amplified common missense variants (minor allele frequency > 0.05). Candidate functional variants were tested for association with gout by multivariable-adjusted regression analysis in 2528 individuals of Polynesian ancestry.

RESULTS

We identified 26 variants common in the Polynesian population and uncommon in the European and East Asian populations. Three of the 26 population-amplified variants were nominally associated with the risk of gout (rs1635712 [KIAA0319], OR_meta = 1.28, P _meta = 0.03; rs16869924 [CLNK], OR_meta = 1.37, P _meta = 0.002; rs2070025 [fibrinogen A alpha chain (FGA)], OR_meta = 1.34, P _meta = 0.02). The CLNK variant, within the established SLC2A9 gout locus, was genetically independent of the association signal at SLC2A9.

CONCLUSION

We provide nominal evidence for the existence of population-amplified genetic variants conferring risk of gout in Polynesian populations. Polymorphisms in CLNK have previously been associated with gout in other populations, supporting our evidence for the association of this gene with gout.

Inequities in people with gout: a focus on Māori (Indigenous People) of Aotearoa New Zealand

Health equity can be defined as the absence of systematic disparities in health between more and less advantaged social groups. Gout is one of the most common forms of arthritis and disproportionally affects Indigenous peoples, including Māori in Aotearoa New Zealand. Inequities in gout management are well documented and clearly evidenced in Indigenous populations. For example, while gout occurs at a younger age and is more severe in Māori, there is less regular dispensing of urate-lowering therapies. Indigenous peoples are also under-represented in clinical trials. Herein, we will review inequities in gout using Aoteoaroa New Zealand as an example. We will explore reasons for health inequities and challenges that need to be faced to achieve health equity.