Sex differences in gout epidemiology: evaluation and treatment

Epidemiology of gout - Global burden of disease research from 1990 to 2019 and future trend predictions

Background

Understanding the global burden of gout in the past and future can provide important references for optimizing prevention and control strategies in healthcare systems.

Objectives

This study aimed to report variations in the global disease burden and risk factors of gout in 204 countries and territories from 1990 to 2019.

Design

We conducted a retrospective analysis of gout based on the latest Global Burden of Disease (GBD) 2019 database.

Methods

We collected data on the prevalence, incidence, and disability-adjusted life years (DALYs) of gout from 1990 to 2019. The data were then stratified by age, sex, and economic development level. Decomposition analysis, frontier analysis, and prediction models were used to analyze the changes and influencing factors influencing each indicator.

Results

Globally, there were 53,871,846.4 [95% uncertainty interval (UI): 43,383,204.6-66,342,327.3] prevalent cases, 92,228,86.8 (95% UI: 7419,132.1-11,521,165) incident cases, and 1673,973.4 (95% UI: 1,068,061.1-2,393,469.2) cases of DALYs of gout in 2019, more than double those in 1990. Moreover, the pace of increase in the age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR), and age-standardized DALY rate (ASDR) accelerated during 1990-2019, with estimated annual percentage changes (EAPC) of 0.94 [95% confidence interval (CI): 0.85-1.03], 0.77 (95% CI: 0.69-0.84), and 0.93 (95% CI: 0.84-1.02), respectively, especially among men. The disease burden of gout has increased in all the other 20 GBD regions in the past 30 years, except Western Sub-Saharan Africa. The highest risk of high body mass index (BMI) and kidney dysfunction was in high-income countries such as North America and East Asia. The global prevalence rate, incidence rate, and DALYs rate of gout in 2030 will reach 599.86, 102.96 per 100,000 population, and 20.26 per 100,000 population, respectively, roughly the same as in 2019.

Conclusion

With the development of society, the disease burden of gout will become increasingly severe. It is very important to study the accurate epidemiological data on gout for clinical diagnosis and treatment and health policy.

Unsupervised cluster analysis of clinical and ultrasound features reveals unique gout subtypes: Results from the Egyptian College of Rheumatology (ECR)

BACKGROUND

Gout comprises a heterogeneous group of disorders; however, comorbidities have been the focus of most efforts to classify disease subgroups.

OBJECTIVES

We applied cluster analysis using musculoskeletal ultrasound (MSUS) combined with clinical and laboratory findings in patients with gout to identify disease phenotypes, and differences across clusters were investigated.

PATIENTS AND METHODS

Patients with gout who complied with the ACR/EULAR classification criteria were enrolled in the Egyptian College of Rheumatology (ECR)-MSUS Study Group, a multicenter study. Selected variables included demographic, clinical, and laboratory findings. MSUS scans assessed the bilateral knee and first metatarsophalangeal joints. We performed a K-mean cluster analysis and compared the features of each cluster.

RESULTS

425 patients, 267 (62.8 %) males, mean age 54.2 ± 10.3 years were included. Three distinct clusters were identified. Cluster 1 (n = 138, 32.5 %) has the lowest burden of the disease and a lower frequency of MSUS characteristics than the other clusters. Cluster 2 (n = 140, 32.9 %) was mostly women, with a low rate of urate-lowering treatment (ULT). Cluster 3 (n = 147, 34.6 %) has the highest disease burden and the greatest proportion of comorbidities. Significant MSUS variations were found between clusters 2 and 3: joint effusion (p < 0.0001; highest: cluster 3), power Doppler signal (p < 0.0001; highest: clusters 2), and aggregates of crystal deposition (p < 0.0001; highest: cluster 3).

CONCLUSION

Cluster analysis using MSUS findings identified three gout subgroups. People with more MSUS features were more likely to receive ULT. Treatment should be tailored according to the cluster and MSUS features.

Risk of gout in Taiwan Biobank participants pertaining to their sex and family history of gout among first-degree relatives

BACKGROUND

Family history of gout and sex are independently associated with gout. However, there is a paucity of research regarding the joint role of both factors in gout pathogenesis. Therefore, we assessed the independent and combined association of family history of gout and sex with gout.

METHODS

Our analysis included 132,311 Taiwan Biobank (TWB)-enrolled individuals comprising 21,159 gout cases and 111,152 controls. We subcategorized the family history of gout as (1) both siblings and parents had gout), (2) only parents had gout, and (3) only siblings had gout.

RESULTS

Generally, sex (men compared to women) and family history of gout were independently associated with a higher risk of gout. The odds ratio (OR); 95% confidence interval (CI) was 9.175; 8.801-9.566 for sex, and 2.306; 2.206-2.410 for family history. For the subcategories 'both siblings and had gout,' 'only parents had gout,' and 'only siblings had gout,' the odds ratios (ORs); 95% confidence intervals (CIs) were 4.944; 4.414-5.538, 2.041; 1.927-2.161, and 2.162; 2.012-2.323, respectively. The interaction between sex and family history was significant (p value = 0.0001). After stratification by sex, family history of gout remained significantly associated with a higher risk of gout in both sexes, even though the odds ratios were higher in men. For the subcategories 'both siblings and parents had gout,' 'only parent had gout,' and 'only siblings had gout,' the corresponding ORs; 95% CIs were 6.279; 5.243-7.520, 2.211; 2.062-2.371, and 2.148; 1.955-2.361 in men and 4.199; 3.566-4.945, 1.827; 1.640-2.035, and 2.093; 1.876-2.336 in women. After integrating sex and family history (reference: women with no family history), the highest risk of gout was observed in men who had at least one parent and sibling with a history of gout (OR; 95% CI 55.774; 46.360-67.101).

CONCLUSION

Sex and family history of gout were independently and interactively associated with gout. Sex-wise, men had a higher risk of gout than women. Family history was associated with a higher risk of gout in both sexes, but men had a higher risk. Notably, men having both siblings and parents with gout had the highest risk of gout.

Sex Differences in the Preventive Effect of Cardiovascular and Metabolic Therapeutics on Dementia

Dementia is a clinical syndrome characterized by progressive impairment of cognitive and functional abilities. As currently applied treatments for dementia can only delay the progression of dementia and cannot fundamentally cure it, much attention is being paid to reducing its incidence by preventing the associated risk factors. Cardiovascular and metabolic diseases are well-known risk factors for dementia, and many studies have attempted to prevent dementia by treating these risk factors. Growing evidence suggests that sex-based factors may play an important role in the pathogenesis of dementia. Therefore, a deeper understanding of the differences in the effects of drugs based on sex may help improve their effectiveness. In this study, we reviewed sex differences in the impact of therapeutics targeting risk factors for dementia, such as cardiovascular and metabolic diseases, to prevent the incidence and/or progression of dementia.

Sex and country differences in gout: cross-country comparison between Sweden and the UK

OBJECTIVE

Compare characteristics, sex differences, and management of gout in Sweden and the UK.

METHOD

The results from two separate primary care gout surveys from Sweden and the UK were compared. Participants aged ≥18 years with gout were sent a questionnaire asking about lifestyle, gout characteristics, uratelowering therapy (ULT), comorbidities, disability, and disease impact. For sex comparison, participants were pooled across countries.

RESULTS

In total, 784 (80% male) participants from Sweden and 500 (87% male) from the UK were included. Swedish patients were significantly older at gout onset, mean (SD) age 72 (12) versus 63 (13) years, (p<0.0001), with more comorbidities, and more frequent use of ULT (48% vs 35%, p=0.0005, age-adjusted). Use of alcohol and diuretics was significantly more common among UK patients, who also reported a higher number of gout flares, mean (SD) 2.2 (1.7) versus 1.6 (3.6), (p=0.003) age-adjusted. Females with gout were older at gout onset, mean (SD) age 67 (13) versus 56 (15), (p<0.0001), more often obese, and reported higher use of diuretics. Furthermore, females reported greater impact of gout, more pain and physical limitations, whereas no sex differences were seen in ULT or flares.

CONCLUSIONS

In the UK, gout was more frequently associated with modifiable risk factors. People with gout in Sweden were more commonly taking ULT and had lower frequency of gout flares and impact of gout. Females with gout more commonly took diuretics, had higher body mass index, and reported greater physical disability, which should be considered when managing gout in women.

Importance of different electronic medical record components for chronic disease identification in a Swiss primary care database: a cross-sectional study

BACKGROUND

Primary care databases collect electronic medical records with routine data from primary care patients. The identification of chronic diseases in primary care databases often integrates information from various electronic medical record components (EMR-Cs) used by primary care providers. This study aimed to estimate the prevalence of selected chronic conditions using a large Swiss primary care database and to examine the importance of different EMR-Cs for case identification.

METHODS

Cross-sectional study with 120,608 patients of 128 general practitioners in the Swiss FIRE ("Family Medicine Research using Electronic Medical Records") primary care database in 2019. Sufficient criteria on three individual EMR-Cs, namely medication, clinical or laboratory parameters and reasons for encounters, were combined by logical disjunction into definitions of 49 chronic conditions; then prevalence estimates and measures of importance of the individual EMR-Cs for case identification were calculated.

RESULTS

A total of 185,535 cases (i.e. patients with a specific chronic condition) were identified. Prevalence estimates were 27.5% (95% CI: 27.3-27.8%) for hypertension, 13.5% (13.3-13.7%) for dyslipidaemia and 6.6% (6.4-6.7%) for diabetes mellitus. Of all cases, 87.1% (87.0-87.3%) were identified via medication, 22.1% (21.9-22.3%) via clinical or laboratory parameters and 19.3% (19.1-19.5%) via reasons for encounters. The majority (65.4%) of cases were identifiable solely through medication. Of the two other EMR-Cs, clinical or laboratory parameters was most important for identifying cases of chronic kidney disease, anorexia/bulimia nervosa and obesity whereas reasons for encounters was crucial for identifying many low-prevalence diseases as well as cancer, heart disease and osteoarthritis.

CONCLUSIONS

The EMR-C medication was most important for chronic disease identification overall, but identification varied strongly by disease. The analysis of the importance of different EMR-Cs for estimating prevalence revealed strengths and weaknesses of the disease definitions used within the FIRE primary care database. Although prioritising specificity over sensitivity in the EMR-C criteria may have led to underestimation of most prevalences, their sex- and age-specific patterns were consistent with published figures for Swiss general practice.

The Impact of Label Changes (Boxed Warning) on Real-World Febuxostat Utilization in Patients with Gout: A Cross-Sectional Drug Utilization Study

INTRODUCTION

This drug utilization study evaluated the impact of 2019 label changes on real-world febuxostat utilization among patients with gout. We describe the numbers and proportions of patients initiating febuxostat as new users (allopurinol-naïve) or prevalent new users (prior allopurinol use) and data on febuxostat users with established cardiovascular disease (CVD) morbidities before, during, and after the 2019 label changes.

METHODS

This descriptive, non-interventional, cross-sectional study used data from two large administrative claims databases in the United States, the IQVIA PharMetrics Plus database and the Optum Research Database (ORD). The study population included patients with gout initiating febuxostat on or after June 1, 2016. Data were collected on febuxostat and allopurinol use, established CVD morbidities, comorbidities of interest, concomitant medications, and patient demographics.

RESULTS

In both databases, the total number of febuxostat users and proportion of patients who initiated febuxostat as new users both decreased during the study period. Of 13,848 patients in the PharMetrics Plus cohort, 42.7% were new users of febuxostat and 57.3% were prevalent new users. In the ORD cohort, 40.5% of the 10,198 patients were new users and 59.5% were prevalent new users. The most common established CVD morbidities in the 12 months prior to initiation of febuxostat were diabetes mellitus, ischemic heart disease, and heart failure/cardiomyopathy.

CONCLUSIONS

Although the benefit-risk profile for febuxostat is considered favorable for the treatment of hyperuricemia in certain patients with gout, real-world febuxostat utilization decreased during the study period, presumably in response to the label change.

Interactions Between Genetic Risk and Diet Influencing Risk of Incident Female Gout: Discovery and Replication Analysis of Four Prospective Cohorts

OBJECTIVE

To examine whether the cross-sectional gene-diet interaction for prevalent hyperuricemia among women translates prospectively to risk of incident female gout.

METHODS

We analyzed the interaction between genetic predisposition and adherence to a healthy dietary pattern (i.e., Dietary Approaches to Stop Hypertension [DASH] score) on risk of incident female gout in 18,244 women from Nurses' Health Study (NHS; discovery) and 136,786 women from 3 additional prospective female cohorts from the US and UK (replication). Genetic risk score (GRS) was calculated from 114 urate-associated loci.

RESULTS

In the NHS and replication cohorts, association between diet and gout risk was larger and stronger among women with higher genetic risk. In all cohorts combined, compared to women with an unhealthy DASH score (less than the mean score), multivariable relative risk (RR) for incident gout among women with a healthy DASH score (greater than/equal to the mean score) was 0.67 (95% confidence interval [95% CI] 0.60-0.76) among higher GRS (greater than/equal to the mean score) and 0.91 (0.78-1.05) among lower GRS (P for multiplicative interaction = 0.001); multivariable RR for higher versus lower GRS was 2.03 (95% CI 1.80-2.29) and 1.50 (95% CI 1.31-1.71) among unhealthy and healthy DASH score groups, respectively. Additive interaction was also significant, in both the discovery and replication cohorts (P < 0.001), with 51% of the excess risk attributable to the additive gene-diet interaction in all cohorts combined.

CONCLUSION

The deleterious effect of genetic predisposition on risk of incident female gout was more pronounced among women with unhealthy diets, with nearly half the excess risk attributable to this gene-diet interaction. These data elucidate the important synergy of genetics and diet for female gout development.

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.

Promoting Cultural Humility by Integrating Health Equity Literature into the Pharmacy Curriculum

Strategies that introduce students to unconscious bias and social determinants of health (SDOH) are critical to develop them as effective health care providers. We developed a semester-long activity that utilizes disease-relevant scientific literature to implement cultural humility training in a second-year rheumatology pharmacy course. Students were first re-introduced to implicit bias and then completed an anonymous survey at the beginning and conclusion of the course using a 5-point Likert scale to assess their perceptions of the role of biases and SDOH in patient care. Throughout the semester, five journal articles were assigned that relate to course material and focus on one characteristic (e.g., gout—gender). Students’ evolved perceptions of SDOH were compared to baseline data and characteristics of assigned articles indicate an improved understanding of SDOH including race/ethnicity (3.0 to 4.4, p < 0.0001); gender (2.8 to 4.0, p < 0.0001); and religion (2.3 to 2.9, p < 0.01). Among characteristics that were not directly discussed in the assignments, only education showed a significant increase (3.0 to 3.6, p < 0.01). Scientific articles that focus on health inequities relevant to course-specific diseases provide a strategy to integrate discussions that help students evaluate their biases and SDOH with the goal of improving patient care.

Febuxostat Therapy for Patients with Gout and Stage 2-4 CKD: a Retrospective Study

Introduction

The aim of this study is to explore the efficacy and renal safety of febuxostat in gout and stage 2–4 chronic kidney disease (CKD) and factors that correlated with target serum urate (SU).

Methods

A single-center retrospective study including male patients with gout and CKD was conducted. SU, the rate of SU < 360 µmol/L (RAT), and renal safety were analyzed in subjects who received febuxostat over 44 weeks. Factors that correlated with target SU were also explored.

Results

Between January 2017 and March 2021, 102 patients (stage 2 CKD: n = 27; stage 3 CKD: n = 70; stage 4 CKD: n = 5) were enrolled. The SU level reduced significantly over 44 weeks (600.76 ± 95.42 versus 405.52 ± 111.93 µmol/L; P < 0.05), and RAT increased to 39.20%. The overall estimated glomerular filtration rate (eGFR) level improved over 44 weeks (52.05 ± 11.68 versus 55.46 ± 14.49 mL/min/1.73 cm², P < 0.05). An obvious improvement of eGFR was observed in stage 3 CKD, in patients with ≤ 1 risk factor (hypertension, diabetic mellitus, hyperlipidemia, or usage of non-steroidal anti-inflammatory drugs), and in patients with terminal SU < 360 µmol/L (P < 0.05). Logistic regression analysis indicated that baseline SU level and body weight were correlated with RAT. Further analysis revealed that patients with SU < 600 μmol/L and body weight ≤ 70 kg reached higher RAT (56.7%).

Conclusions

Febuxostat demonstrated efficacy and renal safety in patients with gout and CKD in clinical practice. Achieving the target SU could obviously improve renal function. Baseline SU level and body weight could affect the achievement of target SU.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-022-00480-7.

Racial and Sex Disparities in Gout Prevalence Among US Adults

IMPORTANCE

Emerging data suggest gout and hyperuricemia may now be more frequent among Black adults in the US than White adults, especially Black women. However, national-level, sex-specific general population data on racial differences in gout prevalence and potential socioclinical risk factors are lacking.

OBJECTIVE

To identify sex-specific factors driving disparities between Black and White adults in contemporary gout prevalence in the US general population.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis used nationally representative, decadal survey data from successive cycles of the National Health and Nutrition Examination Survey from 2007 to 2016. Data were analyzed from November 1, 2019, through May 31, 2021. Participants included US adults self-reporting Black or White race.

EXPOSURES

Self-reported race, excess body mass index, chronic kidney disease (CKD; defined as estimated glomerular filtration rate <60 mL/min/1.73 m2, according to latest equations without race coefficient), poverty, poor-quality diet, low educational level, alcohol consumption, and diuretic use.

MAIN OUTCOMES AND MEASURES

Race- and sex-specific prevalence of physician- or clinician-diagnosed gout and hyperuricemia and their differences before and after adjusting for potential socioclinical risk factors.

RESULTS

A total of 18 693 participants were included in the analysis, consisting of 3304 Black women (mean [SD] age, 44.8 [0.4] years), 6195 White women (mean [SD] age, 49.8 [0.3] years), 3085 Black men (mean [SD] age, 43.6 [0.5] years]), and 6109 White men (mean [SD] age, 48.2 [0.3] years). Age-standardized prevalence of gout was 3.5% (95% CI, 2.7%-4.3%) in Black women and 2.0% (95% CI, 1.5%-2.5%) in White women (age-adjusted odds ratio [OR], 1.81 [95% CI, 1.29-2.53]); prevalence was 7.0% (95% CI, 6.2%-7.9%) in Black men and 5.4% (95% CI, 4.7%-6.2%) in White men (age-adjusted OR, 1.26 [95% CI, 1.02-1.55]). These associations attenuated after adjusting for poverty, diet, body mass index, and CKD among women and for diet and CKD among men but became null after adjusting for all risk factors (ORs, 1.05 [95% CI, 0.67-1.65] among women and 1.05 [95% CI, 0.80-1.35] among men). Hyperuricemia end point findings were similar.

CONCLUSIONS AND RELEVANCE

In this nationally representative race- and sex-specific cross-sectional study of US adults, gout was more prevalent in adults self-reporting Black race during a recent 10-year period compared with their White counterparts. These racial differences may be explained by sex-specific differences in diet and social determinants of health and clinical factors. Culturally informed efforts focusing on these factors could reduce current gout-related disparities.

The Association between Serum Testosterone and Hyperuricemia in Males

Gout is a common systemic inflammatory disease with a male predominance. This study aimed to determine the relationship between serum total testosterone level and hyperuricemia. Data on 1899 men, collected from 2007 to 2017, were included in the analysis. Serum testosterone and urate (SU) were measured on enrolment. The primary endpoints were SU levels ≥ 7 mg/dL and ≥9 mg/dL. On enrolment, participants had a mean age of 45.6 years and mean total testosterone and SU levels of 510 ng/dL and 6.6 mg/dL, respectively. The mean total testosterone levels were 533 and 470 ng/dL in patients with SU levels < 7 mg/dL and ≥7 mg/dL, respectively (p < 0.001); and 515 and 425 ng/dL in patients with SU levels < 9 mg/dL and ≥9 mg/dL, respectively (p < 0.001). After adjusting for age, body mass index, creatinine, serum lipid, fasting blood glucose, systolic blood pressure, and diastolic blood pressure, low testosterone level (<400 ng/dL) was significantly associated with an SU level ≥ 7 mg/dL (hazard ratio: 1.182, 95% confidence interval: 1.005−1.39) and ≥9 mg/dL (hazard ratio: 1.905, 95% confidence interval: 1.239−2.928). In men, a low testosterone level may be associated with an increased risk of hyperuricemia.

Blood Pressure and Stroke: A Review of Sex- and Ethnic/Racial-Specific Attributes to the Epidemiology, Pathophysiology, and Management of Raised Blood Pressure

Raised blood pressure (BP) is the leading cause of death and disability worldwide, and its particular strong association with stroke is well established. Although systolic BP increases with age in both sexes, raised BP is more prevalent in males in early adulthood, overtaken by females at middle age, consistently across all ethnicities/races. However, there are clear regional differences on when females overtake males. Higher BP among males is observed until the seventh decade of life in high-income countries, compared with almost 3 decades earlier in low- and middle-income countries. Females and males tend to have different cardiovascular disease risk profiles, and many lifestyles also influence BP and cardiovascular disease in a sex-specific manner. Although no hypertension guidelines distinguish between sexes in BP thresholds to define or treat hypertension, observational evidence suggests that in terms of stroke risk, females would benefit from lower BP thresholds to the magnitude of 10 to 20 mm Hg. More randomized evidence is needed to determine if females have greater cardiovascular benefits from lowering BP and whether optimal BP is lower in females. Since 1990, the number of people with hypertension worldwide has doubled, with most of the increase occurring in low- and-middle-income countries where the greatest population growth was also seen. Sub-Saharan Africa, Oceania, and South Asia have the lowest detection, treatment, and control rates. High BP has a more significant effect on the burden of stroke among Black and Asian individuals than Whites, possibly attributable to differences in lifestyle, socioeconomic status, and health system resources. Although pharmacological therapy is recommended differently in local guidelines, recommendations on lifestyle modification are often very similar (salt restriction, increased potassium intake, reducing weight and alcohol, smoking cessation). This overall enhanced understanding of the sex- and ethnic/racial-specific attributes to BP motivates further scientific discovery to develop more effective prevention and treatment strategies to prevent stroke in high-risk populations.

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.

Reduced Risk of Sepsis and Related Mortality in Chronic Kidney Disease Patients on Xanthine Oxidase Inhibitors: A National Cohort Study

Background

Advanced chronic kidney disease (CKD) patients are at higher risk of sepsis-related mortality following infection and bacteremia. Interestingly, the urate-lowering febuxostat and allopurinol, both xanthine oxidase inhibitors (XOis), have been suggested to influence the sepsis course in animal studies. In this study, we aim to investigate the relationship between XOis and infection/sepsis risk in pre-dialysis population.

Methods

Pre-dialysis stage 5 CKD patients with gout were identified through the National Health Insurance Research Database (NHIRD) in Taiwan from 2012 to 2016. Outcomes were also compared with national data.

Results

In our nationwide, population-based cohort study, 12,786 eligible pre-dialysis stage 5 CKD patients were enrolled. Compared to non-users, febuxostat users and allopurinol users were associated with reduced sepsis/infection risk [hazard ratio (HR), 0.93; 95% confidence interval (CI), 0.87–0.99; P = 0.0324 vs. HR, 0.92; 95% CI, 0.86–0.99; P = 0.0163]. Significant sepsis/infection-related mortality risk reduction was associated with febuxostat use (HR, 0.68; 95% CI, 0.52–0.87). Subgroup analysis demonstrated preference of febuxostat over allopurinol in sepsis/infection-related mortality among patients younger than 65 years of age, stain users, non-steroidal anti-inflammatory drug non-users, and non-diabetics. There was no significant difference in major adverse cardiac and cerebrovascular event (MACCE) risk between users and non-users while reduced risk of all-cause mortality was observed for XOi users.

Conclusions

Use of XOi in pre-dialysis stage 5 CKD patients may be associated with reduced risk of sepsis/infection and their related mortality without increased MACCE and overall mortality.

Impact of adiposity on risk of female gout among those genetically predisposed: sex-specific prospective cohort study findings over >32 years

OBJECTIVES

To evaluate the joint (combined) association of excess adiposity and genetic predisposition with the risk of incident female gout, and compare to their male counterparts; and determine the proportion attributable to body mass index (BMI) only, genetic risk score (GRS) only, and to their interaction.

METHODS

We prospectively investigated potential gene-BMI interactions in 18 244 women from the Nurses' Health Study and compared with 10 888 men from the Health Professionals Follow-Up Study. GRS for hyperuricaemia was derived from 114 common urate-associated single nucleotide polymorphisms.

RESULTS

Multivariable relative risk (RR) for female gout was 1.49 (95% CI 1.42 to 1.56) per 5 kg/m² increment of BMI and 1.43 (1.35 to 1.52) per SD increment in the GRS. For their joint association of BMI and GRS, RR was 2.18 (2.03 to 2.36), more than the sum of each individual factor, indicating significant interaction on an additive scale (p for interaction <0.001). The attributable proportions of joint effect for female gout were 42% (37% to 46%) to adiposity, 37% (32% to 42%) to genetic predisposition and 22% (16% to 28%) to their interaction. Additive interaction among men was smaller although still significant (p interaction 0.002, p for heterogeneity 0.04 between women and men), and attributable proportion of joint effect was 14% (6% to 22%).

CONCLUSIONS

While excess adiposity and genetic predisposition both are strongly associated with a higher risk of gout, the excess risk of both combined was higher than the sum of each, particularly among women.

Urate transport in health and disease

Circulation of urate levels is determined by the balance between urate production and excretion, homeostasis regulated by the function of urate transporters in key epithelial tissues and cell types. Our understanding of these physiological processes and identification of the genes encoding the urate transporters has advanced significantly, leading to a greater ability to predict risk for urate-associated diseases and identify new therapeutics that directly target urate transport. Here, we review the identified urate transporters and their organization and function in the renal tubule, the intestinal enterocytes, and other important cell types to provide a fuller understanding of the complicated process of urate homeostasis and its role in human diseases. Furthermore, we review the genetic tools that provide an unbiased catalyst for transporter identification as well as discuss the role of transporters in determining the observed significant gender differences in urate-associated disease risk.

Sex differences in response to allopurinol and benzbromarone in gout: a retrospective cohort study

Objective

Owing to lower mean uric acid excretion in women compared with men, uricosuric agents might be preferred in women over xanthine oxidase (XO) inhibitors. We therefore investigated the differences in response to two urate-lowering therapies (ULTs) with different modes of action within and between sexes.

Methods

This retrospective cohort study included patients with a clinical diagnosis of gout who started allopurinol and/or benzbromarone. The successful response to ULT, defined as reaching a serum uric acid (sUA) target of <0.36 mmol/l within 6 months after commencing ULT, was compared between allopurinol and benzbromarone in women and men. Effect modification by sex on differences in response was evaluated.

Results

Allopurinol was started in 255 women and 1045 men, and benzbromarone in 60 women and 205 men. After 6 months, the proportions of women reaching the sUA target were 58.4% and 66.7% for allopurinol and benzbromarone, respectively (difference, −8%; 95% CI: −22%, 5%). The respective proportions in men were 61.0% and 75.6%, respectively (difference, −15%; 95% CI: −21%, −8%). Corrected for confounding, the odds ratio (OR) of reaching the target on benzbromarone vs allopurinol within women was 0.91 (95% CI: 0.47, 1.75), and within men 1.55 (95% CI: 1.04, 2.32). Corrected for confounding, sex was not an effect modifier of the difference in allopurinol and benzbromarone response (OR, 0.59; 95% CI: 0.28, 1.24).

Conclusion

This study did not demonstrate between-sex differences regarding the response to either a uricosuric agent or an XO inhibitor, negating different treatment choices by sex.

Comorbidities and factors influencing frequent gout attacks in patients with gout: a cross-sectional study

OBJECTIVES

The objective was to identify the comorbidities of gout, to compare gender difference and independent factors of frequent gout attacks (> 20 times).

METHOD

Demographic, clinical variables, self-reported comorbidities, and biochemical variables (i.e., initial serum uric acid (UA) and UA at visit) were collected in this cross-sectional study. Gout attack times were recorded as ≤ 5, 6-10, 11-20, and > 20. Adjusted odds ratio (OR) and corresponding 95% confidence interval (CI) were calculated to explore the association between selected risk factors and frequent gout attacks.

RESULTS

Six hundred fifty-three gout patients with a mean age of 48.3 ± 15.8 years were included, 84.7% of whom were males. The median gout duration was 6.0 (3.0-12.0) years. The most common comorbidities involved hypertension (166, 25.4%), coronary artery disease (CAD) (67, 10.3%), chronic kidney disease (66, 10.1%), and hyperlipidemia (57, 8.7%). Abnormalities including nephrolithiasis (29.4%), hydronephrosis (3.2%), and gallstones (11.9%) were also found. Although female patients had a longer disease duration and more CAD, they had a lower level of UA, creatine, and C-reactive protein (CRP) but higher high-density lipoprotein cholesterol (HDL-C) (p < 0.05). A positive correlation between UA and triglycerides was found in females (p = 0.039). Patients with renal insufficiency or nephrolithiasis had longer disease duration and more gout attacks (p < 0.001). In multivariable regression analysis, only gout duration (OR = 7.89, p < 0.001) and UA (OR = 1.48, p < 0.001) was independent factors of frequent gout attacks.

CONCLUSIONS

Comorbidity screening involving dyslipidemia is often neglected in gout patients. Gout duration and UA are the risk factors of frequent gout attacks. Key Points • Comorbidities can be overlooked if the screening for lipid levels, cardiovascular disease, and kidney disease is not completed. • There are differences in comorbidities and biochemical findings between male and female patients with gout. • Gout duration and serum uric acid level are independent risk factors of frequent gout attacks.

Allopurinol-Induced Severe Cutaneous Adverse Drug Reactions: An Analysis of Spontaneous Reports in Malaysia (2000-2018)

INTRODUCTION

Allopurinol-induced severe cutaneous adverse drug reactions (SCARs) are potentially debilitating and life-threatening reactions, which can cause a financial burden to the healthcare system.

OBJECTIVES

We aimed to identify risk factors for allopurinol-induced SCARs and to assess their impact on fatality.

METHODS

Adverse drug reaction (ADR) reports with allopurinol as suspected drug were extracted from the Malaysian pharmacovigilance database from year 2000 to 2018. Multiple logistic regression analysis was used to identify significant predictors of allopurinol-induced SCARs. We further analysed the association between covariates and SCARs-related fatality in a separate model. Level of significance was set at p value < 0.05.

RESULTS

Out of 1747 allopurinol ADR reports, 612 involved SCARs (35%). The strongest predictors significantly associated with SCARs were underlying renal disease (odds ratio [OR] 2.02; 95% confidence interval [CI] 1.36, 3.00; p = 0.001), allopurinol-prescribed dose of 300 mg/day or higher (OR 1.72; 95% CI 1.38, 2.15; p < 0.001), females (OR 1.54; 95% CI 1.24, 1.93; p < 0.001), age 65 years and above (OR 1.31; 95% CI 1.04, 1.64; p = 0.020), and allopurinol-prescribed indication. SCARs cases were higher in patients who received allopurinol for unspecified hyperuricaemia (OR 1.87; 95% CI 1.29, 2.70; p = 0.001) and off-label indications (OR 3.45; 95% CI 2.20, 5.42; p < 0.001) compared to registered indications. Fatality was associated with older age and a diagnosis of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) overlap or TEN.

CONCLUSIONS

Malaysian pharmacovigilance data show that predictors of allopurinol-induced SCARs were elderly females, patients with underlying renal disease and high allopurinol doses. These patients need close monitoring and must be educated to stop allopurinol at the first signs of rash.

Allopurinol adherence and its predictors in gout: a national cohort study in US veterans

Background

Allopurinol is a frequently used, effective, and affordable medication for gout. However, poor adherence to allopurinol is a key reason for patients not reaching treatment goals. The aim of this study was to comprehensively assess factors associated with high allopurinol adherence in gout.

Methods

In this national cohort study, we used the health-care databases of the US Department of Veterans Affairs (VA) from 2002 to 2016 and a new-user design to assess potential predicting factors of allopurinol adherence. Veterans were included in this study if they had International Classification of Diseases (ninth revision) code 274.x for gout in two or more outpatient encounters or one or more inpatient encounters during 2002-16; incident allopurinol use; and at least 12 months of observation. Potential predictors of allopurinol adherence (defined as medication possession ratio [days used divided by days prescribed] of >80%) were examined using Andersen's health-care utilisation model and multivariable-adjusted logistic regression analyses.

Findings

Between Oct 1, 2002, and Sept 30, 2016, 565 812 potentially eligible patients were included in the VA database, of whom 264 614 (46·8%) met the eligibility criteria and were included in the study cohort. The mean age was 67·8 years (SD 11·7) and mean body-mass index was 33·0 kg/m² (6·4). Factors significantly associated with higher odds of allopurinol adherence in multivariable-adjusted analyses were older age (odds ratio 1·01, 95% CI 1·01-1·01); Deyo-Charlson comorbidity index score of 1 (1·05, 1·02-1·07) or 2 or more (1·05, 1·03-1·07) versus a score of 0; higher body-mass index (all categories from 25 to <30 [1·12, 1·08-1·17] to ≥45 [1·47, 1·39-1·55] vs 18·5 to <25); a military service connection of 50% or higher (1·37, 1·29-1·46) versus 0%; care in a community-based outpatient clinic (1·11, 1·08-1·14) versus in a VA Medical Center; and rural residence (1·02, 1·00-1·05). Factors significantly associated with lower odds of allopurinol adherence were black (0·74, 0·72-0·76), Hispanic (0·68, 0·65-0·72), or other race or ethnicity (0·86, 0·82-0·89) versus white race; non-rheumatologist care provider (0·83, 0·79-0·88); allopurinol start dose of 101-200 mg per day (0·93, 0·91-0·95) or more than 300 mg per day (0·75, 0·72-0·79) versus 100 mg per day or less; or allopurinol use in the previous year (0·80, 0·79-0·82). Compared with residence in the Midwest, patients in other US regions had lower odds of adherence (mid-Atlantic 0·89, 0·87-0·92; northeast 0·84, 0·81-0·87; south 0·85, 0·83-0·88; west 0·86, 0·83-0·89). Compared with a baseline serum urate of 360 to less than 480 μmol/L, serum urate of less than 360 μmol/L was associated with higher odds of adherence (1·28, 1·25-1·32), whereas baseline serum urate of 480 to less than 600 μmol/L (0·86, 0·84-0·88) or 600 to less than 720 μmol/L (0·92, 0·89-0·94) was associated with lower odds of adherence.

Interpretation

We identified several important factors associated with high allopurinol adherence. Clinicians and policy makers can now target modifiable factors at the patient, provider, or systems level, with the aim of improving allopurinol adherence, and thereby overall gout care.

IL-33/ST2 induces neutrophil-dependent reactive oxygen species production and mediates gout pain

Objective: Gout, induced by monosodium urate (MSU) crystal deposition in joint tissues, provokes severe pain and impacts life quality of patients. However, the mechanisms underlying gout pain are still incompletely understood.

Methods: We established a mouse gout model by intra-articularly injection of MSU crystals into the ankle joint of wild type and genetic knockout mice. RNA-Sequencing, in vivo molecular imaging, Ca²⁺ imaging, reactive oxygen species (ROS) generation, neutrophil influx and nocifensive behavioral assays, etc. were used.

Results: We found interleukin-33 (IL-33) was among the top up-regulated cytokines in the inflamed ankle. Neutralizing or genetic deletion of IL-33 or its receptor ST2 (suppression of tumorigenicity) significantly ameliorated pain hypersensitivities and inflammation. Mechanistically, IL-33 was largely released from infiltrated macrophages in inflamed ankle upon MSU stimulation. IL-33 promoted neutrophil influx and triggered neutrophil-dependent ROS production via ST2 during gout, which in turn, activated transient receptor potential ankyrin 1 (TRPA1) channel in dorsal root ganglion (DRG) neurons and produced nociception. Further, TRPA1 channel activity was significantly enhanced in DRG neurons that innervate the inflamed ankle via ST2 dependent mechanism, which results in exaggerated nociceptive response to endogenous ROS products during gout.

Conclusions: We demonstrated a previous unidentified role of IL-33/ST2 in mediating pain hypersensitivity and inflammation in a mouse gout model through promoting neutrophil-dependent ROS production and TRPA1 channel activation. Targeting IL-33/ST2 may represent a novel therapeutic approach to ameliorate gout pain and inflammation.

The management of gout in Africa: challenges and opportunities

The rise in non-communicable diseases in Africa presents challenges for health systems that are burdened by infectious diseases. Gout is one of those diseases that has seen an increase in numbers worldwide, including Africa. Gout is commonly associated with comorbidities and mortality. It directly impacts the quality of life, increases health costs, decreases physical function, and significantly increases the time from work, much of which is potentially avoided if treatment is instituted early. Despite advances in understanding the pathophysiology and outcomes of gout, the quality of care delivered to patients in Africa is still suboptimal. Existing data on gout in Africa reveals a general low index of suspicion due to limited knowledge of the disease by healthcare workers resulting in late diagnosis, with severe polyarticular tophaceous gout being a common presenting feature. These late presentations are associated with avoidable disability and increase the direct and indirect costs of managing gout. The challenges are related to lack of government budgetary support for staff training, infrastructure for diagnosis, and availing medicines. The picture of gout in Africa largely mirrors the west concerning risk factors, comorbidities, and burden of disease, but with some unique presentations seen in HIV, sickle cell disease, and vertigo. We discuss the challenges of gout diagnosis and management in Africa and propose a roadmap to improve gout outcomes across Africa.

Gender and Ethnic Inequities in Gout Burden and Management

Although effective and low-cost urate-lowering therapy has been available for decades, inequities in gout management exist. Despite high impact of disease, rates of urate-lowering therapy prescription are low in women, in African-Americans in the United States, in Māori (Indigenous New Zealanders), and in Pacific peoples living in Aotearoa/New Zealand. Social determinants of health, barriers to accessing the health care system, health literacy demands, stigmatization, and bias contribute to inequities in gout burden and management. Approaches that focus on building health literacy and delivering culturally safe care lead to improved outcomes in gout, and offer important solutions to achieve health equity.

Sex Differences in the Clinical Profile Among Patients With Gout: Cross-sectional Analyses of an Observational Study

OBJECTIVE

Research findings in gout result predominantly from studies about men and might not be generalizable to women. To improve insight into sex differences in gout, our study compared clinical characteristics and comorbidities of female and male patients with gout, and explored the influence of menopause on these differences.

METHODS

Data from patients referred to 2 rheumatology clinics and diagnosed with gout were used. Clinical characteristics and comorbidities of each sex were compared univariately. Sex difference in comorbidities were further explored in multivariate logistic regression analyses adjusting for age, BMI, smoking, and alcohol consumption in both the total group and in those with gout onset ≥ 55 years (as a surrogate for menopausal state).

RESULTS

There were 954 patients, including 793 (83%) men, included. Women were on average older (65 vs 62 yrs), were more often obese (54% vs 36%), had a higher serum uric acid (sUA) level (0.53 vs 0.49 mmol/L), used diuretics more often (60% vs 30%), and consumed alcohol less frequently (47% vs 72%). Additionally, women more frequently had reduced renal function (64% vs 31%), hypertension (78% vs 56%), heart failure (23% vs 12%), and type 2 diabetes (39% vs 17%; all P < 0.05). In those with gout onset ≥ 55 years, differences in comorbidities were less pronounced and disappeared after adjusting for lifestyle.

CONCLUSION

Our study confirmed sex differences in clinical characteristics and comorbidities among newly diagnosed patients with gout, and revealed that sex differences in comorbidities among those with gout onset beyond the age of female menopause were strongly attenuated and fully explained by lifestyle.

Sex Differences in Urate Handling

Hyperuricemia, or elevated serum urate, causes urate kidney stones and gout and also increases the incidence of many other conditions including renal disease, cardiovascular disease, and metabolic syndrome. As we gain mechanistic insight into how urate contributes to human disease, a clear sex difference has emerged in the physiological regulation of urate homeostasis. This review summarizes our current understanding of urate as a disease risk factor and how being of the female sex appears protective. Further, we review the mechanisms of renal handling of urate and the significant contributions from powerful genome-wide association studies of serum urate. We also explore the role of sex in the regulation of specific renal urate transporters and the power of new animal models of hyperuricemia to inform on the role of sex and hyperuricemia in disease pathogenesis. Finally, we advocate the use of sex differences in urate handling as a potent tool in gaining a further understanding of physiological regulation of urate homeostasis and for presenting new avenues for treating the constellation of urate related pathologies.

Hyperuricemia and Hypertension, Coronary Artery Disease, Kidney Disease: From Concept to Practice

Since the publication of the Framingham Heart Study, which suggested that uric acid should no longer be associated with coronary heart disease after additional adjustment for cardiovascular disease risk factors, the number of publications challenging this statement has dramatically increased. The aim of this paper was to review and discuss the most recent studies addressing the possible relation between sustained elevated serum uric acid levels and the onset or worsening of cardiovascular and renal diseases. Original studies involving American teenagers clearly showed that serum uric acid levels were directly correlated with systolic and diastolic pressures, which has been confirmed in adult cohorts revealing a 2.21-fold increased risk of hypertension. Several studies involving patients with coronary artery disease support a role for serum uric acid level as a marker and/or predictor for future cardiovascular mortality and long-term adverse events in patients with coronary artery disease. Retrospective analyses have shown an inverse relationship between serum uric acid levels and renal function, and even a mild hyperuricemia has been shown to be associated with chronic kidney disease in patients with type 2 diabetes. Interventional studies, although of small size, showed that uric acid (UA)-lowering therapies induced a reduction of blood pressure in teenagers and a protective effect on renal function. Taken together, these studies support a role for high serum uric acid levels (>6 mg/dL or 60 mg/L) in hypertension-associated morbidities and should bring awareness to physicians with regards to patients with chronic hyperuricemia.

Hypersensitivity reactions with allopurinol and febuxostat: a study using the Medicare claims data

OBJECTIVE

To assess the risk of hypersensitivity reactions (HSRs) with allopurinol and febuxostat in a population-based study.

METHODS

We used the 5% Medicare beneficiary sample (≥65 years) from 2006 to 2012 to identify people with a newly filled prescription for allopurinol, febuxostat or colchicine. We used multivariable-adjusted Cox regression analyses to compare the hazard ratio (HR) of incident HSRs with allopurinol or febuxostat use versus colchicine use; separate analyses were done in people exposed to allopurinol. Propensity-matched analyses (5:1) compared hazards with allopurinol versus febuxostat.

RESULTS

Crude incidence rates of HSRs were as follows: allopurinol, 23.7; febuxostat, 30.7; and colchicine, 25.6 per 1000 person-years. Compared with colchicine, allopurinol, febuxostat and febuxostat+colchicine were associated with significantly higher HRs of HSRs, 1.32 (95% CI: 1.10 to 1.60) and 1.54 (95% CI: 1.12 to 2.12) and 2.17 (95% CI: 1.18 to 3.99), respectively. In propensity-matched analyses, febuxostat did not significantly differ from allopurinol; HR for HSRs was 1.25 (95% CI: 0.93 to 1.67). Compared with allopurinol start dose <200 mg/day, allopurinol start dose ≥300 mg/day, diabetes and female sex were associated with significantly higher hazard of HSRs, 1.27 (95% CI: 1.12 to 1.44), 1.21 (95% CI: 1.00 to 1.45) and 1.32 (95% CI: 1.17 to 1.48), respectively. The majority (69%) of HSRs occurred in the outpatient setting.

CONCLUSIONS

Compared with colchicine, allopurinol and febuxostat similarly increased the risk of HSRs. Allopurinol and febuxostat did not differ from each other. In allopurinol users, starting dose, female sex and diabetes increased this risk, findings that need further study.

Clinical features and recurrent attack in gout patients according to serum urate levels during an acute attack

BACKGROUND/AIMS

A substantial portion of gout patients have normal serum urate levels during an acute attack but data on the clinical characteristics and risk of recurrence compared with hyperuricemic patients are limited.

METHODS

In this retrospective cohort study, clinical features of normouricemic and hyperuricemic patients were compared. Multivariate analysis was performed to determine whether normouricemic patients were less likely to have a recurrent attack.

RESULTS

Among a total of 221 gout patients, 88 (39.8%) had normouricemia during an acute attack. Postsurgical gout (22.7% vs. 6.0%, p < 0.001), hemodialysis initiation (9.1% vs. 2.3%, p = 0.029) and inflammatory activity were higher in normouricemic patients than in hyperuricemic patients. The frequency of renal insufficiency was lower in normouricemic patients (25.0% vs. 53.4%, p < 0.001). However, the recurrence rate of gout attack was not different between the two groups (24.7% vs. 33.0%, p = 0.220). In multivariate analysis, female sex, history of urinary stone, presence of tophi, and use of thiazide were associated with increase of recurrent gout attack, but not with serum urate status during an acute attack (hazard ratio, 1.075; 95% confidence interval, 0.972 to 1.190; p = 0.159).

CONCLUSION

Normouricemia during an acute gout attack was more frequently observed in postsurgical episodes, hemodialysis initiation and patients with preserved renal function. While higher inflammatory activity was observed in normouricemic patients, recurrent attack was not associated with serum urate levels during an acute attack. Thus, careful follow-up should be considered in gout patients regardless of serum urate levels during an acute attack.

Population-specific factors associated with fractional excretion of uric acid

Background

Reduced renal clearance of uric acid is a major contributor to hyperuricemia. The aim of this study was to examine clinical and genetic variables associated with fractional excretion of uric acid (FEUA).

Methods

Participants (with and without gout) in the Genetics of Gout in Aotearoa study with available genotyping and FEUA data were included (n = 1713). Ten FEUA-associated loci detected within a genome-wide association study for serum urate in a European population were analysed. A polygenic score for FEUA was calculated in each ancestry group to model the cumulative effects of the genetic variants on FEUA. Associations between FEUA and both clinical variables and polygenic score were tested using linear regression models.

Results

The mean (SD) FEUA was 5.13 (2.70) % in Eastern Polynesian participants, 4.70 (5.89) % in Western Polynesian participants, and 5.89 (2.73) % in New Zealand European participants. Although association with FEUA was observed for SLC2A9 rs11942223 in New Zealand European participants (P = 2.39 × 10^− 8), this association was not observed in Eastern or Western Polynesian participants. The polygenic score was positively associated with FEUA in all ancestry groups. In New Zealand European participants, body mass index, diuretic use, polygenic score, and male sex were associated with FEUA and explained 22% of FEUA variance in the regression model. In Eastern and Western Polynesian participants, the tested variables explained 10% and 4% of FEUA variance respectively.

Conclusions

Both clinical and genetic variables contribute to renal clearance of uric acid. SLC2A9 exerts effects on FEUA variance in people of European ancestry, but not in those of Polynesian ancestry. There is a large unexplained variance in FEUA, particularly in people of Polynesian ancestry.

Impact of gout on in-hospital outcomes of acute coronary syndrome-related hospitalizations and revascularizations: Insights from the national inpatient sample

BACKGROUND

Previous studies have established a role of gout in predicting risk and prognosis of cardiovascular diseases. However, large-scale data on the impact of gout on inpatient outcomes of acute coronary syndrome (ACS)-related hospitalizations and post-revascularization is inadequate.

AIM

To evaluate the impact of gout on in-hospital outcomes of ACS hospitalizations, subsequent healthcare burden and predictors of post-revascularization inpatient mortality.

METHODS

We used the national inpatient sample (2010-2014) to identify the ACS and gout-related hospitalizations, relevant comorbidities, revascularization and post-revascularization outcomes using the ICD-9 CM codes. A multivariable analysis was performed to evaluate the predictors of post-revascularization in-hospital mortality.

RESULTS

We identified 3144744 ACS-related hospitalizations, of which 105198 (3.35%) also had gout. The ACS-gout cohort were more often older white males with a higher prevalence of comorbidities. Coronary artery bypass grafting was required more often in the ACS-gout cohort. Post-revascularization complications including cardiac (3.2% vs 2.9%), respiratory (3.5% vs 2.9%), and hemorrhage (3.1% vs 2.7%) were higher whereas all-cause mortality was lower (2.2% vs 3.0%) in the ACS-gout cohort (P < 0.001). An older age (OR 15.63, CI: 5.51-44.39), non-elective admissions (OR 2.00, CI: 1.44-2.79), lower household income (OR 1.44, CI: 1.17-1.78), and comorbid conditions predicted higher mortality in ACS-gout cohort undergoing revascularization (P < 0.001). Odds of post-revascularization in-hospital mortality were lower in Hispanics (OR 0.45, CI: 0.31-0.67) and Asians (OR 0.65, CI: 0.45-0.94) as compared to white (P < 0.001). However, post-operative complications significantly raised mortality odds. Mean length of stay, transfer to other facilities, and hospital charges were higher in the ACS-gout cohort.

CONCLUSION

Although gout was not independently associated with an increased risk of post-revascularization in-hospital mortality in ACS, it did increase post-revascularization complications.

The Interaction between Sex and Hyperlipidemia on Gout Risk Is Modulated by HLA-B Polymorphic Variants in Adult Taiwanese

The effects of genetic variants on the interaction between hyperlipidemia and sex have not been investigated among gout patients in Taiwan. Using Taiwan Biobank and the National Health Insurance Research Database (NHIRD), we examined hyperlipidemia, sex, and their relationship with gout among Taiwanese adults with the human leukocyte antigen B (HLA-B) genetic variants. Hyperlipidemia was present in 1437 patients with gout. Sex and hyperlipidemia had significant associations on gout risk, with hyperlipidemia showing a relatively stronger effect. Gout was present in men, with an odds ratio (OR) of 1.945 (95% confidence interval (CI) 1.568–2.411) compared to women, and in hyperlipidemic (OR = 4.032; 95% CI: 3.581–4.540) compared to non-hyperlipidemic patients. The interaction of sex and hyperlipidemia was significant for rs2523608 GG (p = 0.0402) and rs4713518 AA (p = 0.0003) genotypes. After stratification, hyperlipidemia remained a risk factor in women (OR = 4.735, 95% CI: 3.375–6.643) and men (OR = 3.640, 95% CI: 2.916–4.544) with rs2523608 GG genotype. The odds ratio in hyperlipidemic women and men with rs4713518 AA genotype was 7.454 (95% CI 5.103–10.888) and 3.585 (95% CI 2.854–4.503), respectively. Our study indicates that hyperlipidemia-sex interactions exist for gout risk in Taiwanese adults with rs2523608 GG and rs4713518 AA genotypes.

The impact of dysfunctional variants of ABCG2 on hyperuricemia and gout in pediatric-onset patients

BACKGROUND

ABCG2 is a high-capacity urate transporter that plays a crucial role in renal urate overload and extra-renal urate underexcretion. Previous studies have suggested an association between hyperuricemia and gout susceptibility relative to dysfunctional ABCG2 variants, with rs2231142 (Q141K) being the most common. In this study, we analyzed the ABCG2 gene in a hyperuricemia and gout cohort focusing on patients with pediatric-onset, i.e., before 18 years of age.

METHOD

The cohort was recruited from the Czech Republic (n = 234) and consisted of 58 primary hyperuricemia and 176 gout patients, with a focus on pediatric-onset patients (n = 31, 17 hyperuricemia/14 gouts); 115 normouricemic controls were used for comparison. We amplified, sequenced, and analyzed 15 ABCG2 exons. The chi-square goodness-of-fit test was used to compare minor allele frequencies (MAF), and the log-rank test was used to compare empirical distribution functions.

RESULTS

In the pediatric-onset cohort, two common (p.V12M, p.Q141K) and three very rare (p.K360del, p.T421A, p.T434M) allelic ABCG2 variants were detected. The MAF of p.Q141K was 38.7% compared to adult-onset MAF 21.2% (OR = 2.4, P = 0.005), to the normouricemic controls cohort MAF 8.5% (OR = 6.8, P <  0.0001), and to the European population MAF 9.4% (OR = 5.7, P <  0.0001). The MAF was greatly elevated not only among pediatric-onset gout patients (42.9%) but also among patients with hyperuricemia (35.3%). Most (74%) of the pediatric-onset patients had affected family members (61% were first-degree relatives).

CONCLUSION

Our results show that genetic factors affecting ABCG2 function should be routinely considered in a hyperuricemia/gout diagnosis, especially in pediatric-onset patients. Genotyping of ABCG2 is essential for risk estimation of gout/hyperuricemia in patients with very early-onset and/or a family history.

The Prevalence of Hyperuricemia Sharply Increases from the Late Menopausal Transition Stage in Middle-Aged Women

The impact of menopausal transition on change of serum uric acid level remains unknown. The present study evaluated the relationship of menopausal stages with prevalent hyperuricemia in middle-aged women. This cross-sectional study included 58,870 middle-aged Korean women, aged ≥40, who participated in a health examination from 2014 to 2016. Menopausal stages were obtained with a standardized, self-administered questionnaire and were categorized according to the criteria of the Stages of Reproductive Aging Workshop (STRAW+10). Hyperuricemia was defined as a serum uric acid level of ≥6 mg/dL. The prevalence of hyperuricemia increased as menopausal stage increased. The multivariable-adjusted odds ratios (95% confidence intervals) for prevalent hyperuricemia comparing early transition, late transition, and post-menopause to pre-menopause were 1.19 (0.80–1.77), 2.13 (1.35–3.36), and 1.65 (1.33–2.04), respectively. This association was stronger among non-obese compared to obese participants and in those with low high-sensitivity C-reactive protein (hsCRP) levels (<1.0 mg/L) compared to those with elevated hsCRP levels of ≥1.0 mg/L (p for interaction = 0.01). In this large sample of middle-aged women, the prevalence of hyperuricemia significantly increased from the menopausal stage of late transition, independent of potential confounders. Appropriate preventive strategies for reducing hyperuricemia and its related consequences should be initiated prior to menopause.

Patients Presenting with a Hot, Swollen Joint: A Single-Centre Retrospective Analysis

BACKGROUND

A hot, swollen joint is a common clinical condition encountered in the ED and elective orthopaedic and rheumatology clinics. These patients can be difficult to manage and properly treat.

AIMS AND OBJECTIVES

The aim of this study was to report a single centre retrospective analysis of patients presenting to our institution for a hot, swollen joint over a three-month period.

METHODS

The study included patients presenting with a hot, swollen joint to ED or electively to clinics. The synovial fluid was aspirated and sent for microbiological and cytological investigation. P value was set to < 0.001. 36 patients (22 M, 14 F) with a mean age of 72.8 ± 17.4 years met our criteria. 20 cases (55.6 %) involved the knee joint, the wrist in 10 cases (27.8%), the elbow in 3 cases (8.3%) and the shoulder in 3 cases (8.3%).

RESULTS

Of the 36 synovial fluid samples collected, only 7 (19.4%) reported evidence of infection. On cytological examination of the synovial fluid, 21 (58.3%) reported presence of calcium pyrophosphates crystals (Pseudogout), 4 (11.1 %) reported presence of uric acid crystals (Gout) and 11 (30.5%) reported absence of crystals. We found a significant correlation between age and the diagnosis of pseudogout and between previous antibiotic treatment and ED presentation. Our study sheds light on the high incidence of crystal-related pathologies.

CONCLUSION

In order to improve our management of this common condition and enhance our understanding of the clinical diagnosis in certain patient population, further high-profile clinical studies are needed.

Interactions between serum urate-associated genetic variants and sex on gout risk: analysis of the UK Biobank

BACKGROUND

Sex-specific differences in the effect of genetic variants on serum urate levels have been described. The aim of this study was to systematically examine whether serum urate-associated genetic variants differ in their influence on gout risk in men and women.

METHODS

This research was conducted using the UK Biobank Resource. Thirty single nucleotide polymorphisms (SNPs) associated with serum urate were tested for their association with gout in men and women of European ancestry, aged 40-69 years. Gene-sex interactions for gout risk were analysed using an interaction analysis in logistic regression models.

RESULTS

Gout was present in 6768 (4.1%) men and 574 (0.3%) women, with an odds ratio (95% confidence interval) for men 13.42 (12.32-14.62) compared with women. In men, experiment-wide association with gout was observed for 21 of the 30 serum urate-associated SNPs tested, and in women for three of the 30 SNPs. Evidence for gene-sex interaction was observed for ABCG2 (rs2231142) and PDZK1 (rs1471633), with the interaction in ABCG2 driven by an amplified effect in men and in PDZK1 by an absence of effect in women. Similar findings were observed in a sensitivity analysis which excluded pre-menopausal women. For the other SNPs tested, no significant gene-sex interactions were observed.

CONCLUSIONS

In a large population of European ancestry, ABCG2 and PDZK1 gene-sex interactions exist for gout risk, with the serum urate-raising alleles exerting a greater influence on gout risk in men than in women. In contrast, other serum urate-associated genetic variants do not demonstrate significant gene-sex interactions for gout risk.

mHealth App Patient Testing and Review of Educational Materials Designed for Self-Management of Gout Patients: Descriptive Qualitative Studies

BACKGROUND

Gout is a form of chronic arthritis caused by elevated serum uric acid (SUA) and culminates in painful gout attacks. Although effective uric acid-lowering therapies exist, adherence is low. This is partly due to the lack of support for patients to self-manage their disease. Mobile health apps have been used in the self-management of chronic conditions. However, not all are developed with patients, limiting their effectiveness.

OBJECTIVE

The objective of our study was to collect feedback from gout patients to design an effective gout self-management app.

METHODS

Two descriptive qualitative studies were conducted. In Study 1, researchers developed a short educational video and written materials about gout management, designed to be embedded into an app; 6 interviews and 1 focus group were held with gout patients to gather feedback on these materials. Usability testing in Study 2 involved additional gout patients using a pilot version of Healthy.me Gout, a gout self-management app, for 2 weeks. Following the trial, patients participated in an interview about their experiences using the app.

RESULTS

Patients viewed the gout educational material positively, appreciating the combined use of video, text, and images. Patients were receptive to using a mobile app to self-manage their gout. Feedback about Healthy.me Gout was generally positive with patients reporting that the tracking and diary features were most useful. Patients also provided suggestions for improving the app and educational materials.

CONCLUSIONS

These studies involved patients in the development of a gout self-management app. Patients provided insight to improve the app's presentation and usability and general lessons on useful features for chronic disease apps. Gout patients enjoyed tracking their SUA concentrations and gout attack triggers. These capabilities can be translated into self-management apps for chronic diseases that require monitoring of pathological values, medication adherence, or symptoms. Future health app design should integrate patient input and be developed iteratively to address concerns identified by patients.

Long-term adherence and persistence with febuxostat among male patients with gout in a routine clinical setting

Objectives: To assess long-term adherence and persistence to febuxostat (FBX) and factors that might contribute to non-adherence and non-persistence to FBX in male patients with gout during a 3-year period. Methods: Adherence to FBX was assessed by the clinic nurses through pill counts at the scheduled visits and non-adherence was defined as less than 80% of the prescribed dose taken. Non-persistence was defined as discontinuation of FBX longer than 60 days. Results: A total of 220 patients were recruited. The percentage of adherence and persistence was 71.8% and 80.9% at 1 year, 65.5% and 68.2% at 2 years and 58.2% and 56.4% at 3 years, respectively. The logistic regression analysis identified high income status, current smoking, absence of hypertension and previous history of non-persistence with urate-lowering therapy (ULT) as the independent factors associated with non-adherence, and the unmarried, absence of hypertension and previous history of non-persistence with ULT as the independent factors associated with non-persistence. Conclusion: Variable risk factors that are correlated with poor adherence or persistence and easily assessed can be used to identify patients at a particular risk of poor adherence or persistence.

Comorbidity in gout at the time of first diagnosis: sex differences that may have implications for dosing of urate lowering therapy

Background

The aim of this study is to examine the occurrence of comorbidities at the time of first diagnosis of gout compared with matched population controls, overall and by sex, as well as to examine the crude and age-standardized prevalence of these comorbidities in men and women with gout at first diagnosis.

Methods

A population-based study used data from Swedish national and regional registers, including 14,113 gout patients aged ≥ 20 years, with a first recorded diagnosis of gout between 1 January 2006 and 31 December 2012, and 65,782 population controls, matched by age, sex and county. Prevalence ratios (95% confidence intervals) comparing gout cases and controls were calculated, overall and by sex. Crude and age-standardized prevalence (95% confidence interval) of all comorbidities in gout patients were calculated, to show differences between sexes, taking also the higher age at diagnosis in women into account.

Results

All examined comorbidities were 1.2–2.5-fold more common in gout patients at diagnosis than in population controls in both sexes. Women with gout were on average 6 years older than men at first gout diagnosis and most comorbidities, including obesity and diuretic use, were or tended to be more frequent in women than in men. When standardizing for age, women had a higher prevalence of thromboembolism (6.6% vs 5.2%) and chronic obstructive pulmonary disease (3.1% vs 2.4%). Men, on the other hand, had a higher prevalence of coronary heart disease (9.4% vs 6.4%), atrial fibrillation (9.0% vs 6.0%), congestive heart failure (7.7% vs 6.6%) and stroke (4.1% vs 3.3%).

Conclusions

The occurrence of most comorbidities was significantly increased at first diagnosis of gout in both sexes. Women were older at diagnosis and had higher occurrence of most comorbidities, including obesity and diuretic use, factors that increase serum urate, and this needs to be taken into account when starting and optimizing urate lowering therapy. These sex differences were attenuated when standardizing for age and the occurrence of cardiovascular diseases was actually higher in men.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1596-x) contains supplementary material, which is available to authorized users.

Pseudogout among Patients Fulfilling a Billing Code Algorithm for Calcium Pyrophosphate Deposition Disease

To test the performance of a billing claims-based calcium pyrophosphate deposition disease (CPPD) algorithm for identifying pseudogout. We applied a published CPPD algorithm at an academic institution and randomly selected 100 patients for electronic medical record review for 3 phenotypes: (1) definite/probable CPPD, (2) definite/probable pseudogout; (3) definite pseudogout. Clinical data were recorded and positive predictive value (PPV) (95% CI) for each phenotype was calculated. We then modified the published algorithm to require ≥ 1 of 4 relevant terms ("pseudogout", "calcium pyrophosphate crystals", "CPPD", or "chondrocalcinosis") through automated text searching in clinical notes, and re-calculated PPVs. To estimate the percentage of pseudogout patients not identified by the published algorithm, we reviewed a random sample of 50 patients with ≥ 1 of 4 relevant terms in clinical notes who did not fulfill the published algorithm. Among patients fulfilling the published algorithm, 68% had ≥ 1 of 3 phenotypes. The published algorithm had PPV 24.0% (95% CI 19.3-28.7%) for definite/probable pseudogout and 18.0% (95% CI 14.5-21.5%) for definite pseudogout. Requiring ≥ 1 of 4 relevant terms in clinical notes increased PPV to 33.3% (95% CI 26.8-39.8%) for definite/probable pseudogout and 24.6% (95% CI 19.8-29.4%) for definite pseudogout. Among patients not fulfilling the published algorithm, 16.0% had definite/probable pseudogout and 6.0% had definite pseudogout. A billing code-based CPPD algorithm had low PPV for identifying pseudogout. Adding text searching modestly enhanced the PPV, though it remained low. These findings highlight the need for improved approaches to identify pseudogout to facilitate epidemiologic studies.

Health-related quality of life in gout in primary care: Baseline findings from a cohort study

Objectives

To examine gout-related, comorbid, and sociodemographic characteristics associated with generic and disease-specific health-related quality of life (HRQOL) in gout.

Methods

Adults with gout from 20 general practices were mailed a questionnaire containing the Health Assessment Questionnaire-Disability Index (HAQ-DI), Short-Form-36 Physical Function subscale (PF-10), Gout Impact Scale (GIS), and questions about gout-specific, comorbid and sociodemographic characteristics. Variables associated with HRQOL were examined using multivariable linear regression models.

Results

A total of 1184 completed questionnaires were received (response 65.9%). Worse generic and gout-specific HRQOL was associated with frequent gout attacks (≥5 attacks PF-10 β = −4.90, HAQ-DI β = 0.14, GIS subscales β = 8.94, 33.26), current attack (HAQ-DI β = 0.15, GIS β = −1.94, 18.89), oligo/polyarticular attacks (HAQ-DI β = 0.11, GIS β = 0.78, 7.86), body pain (PF-10 β = −10.68, HAQ-DI β = 0.29, GIS β = 2.61, 11.89), anxiety (PF-10 β = −1.81, HAQ-DI β = 0.06, GIS β = 0.38, 1.70), depression (PF-10 β = −1.98, HAQ-DI β = 0.06, GIS 0.42, 1.47) and alcohol non-consumption (PF-10 β = −16.10, HAQ-DI β = 0.45). Gout-specific HRQOL was better in Caucasians than non-Caucasians (GIS β = −13.05, −13.48). Poorer generic HRQOL was associated with diabetes mellitus (PF-10 β = −4.33, HAQ-DI β = 0.14), stroke (PF-10 β = −12.21, HAQ-DI β = 0.37), renal failure (PF-10 β = −9.43, HAQ-DI β = 0.21), myocardial infarction (HAQ-DI β = 0.17), female gender (PF-10 β = −17.26, HAQ-DI β = 0.43), deprivation (PF-10 β = −7.80, HAQ-DI β = 0.19), and body mass index ≥35 kg/m² (PF-10 β = −6.10, HAQ-DI β = 0.21).

Conclusions

HRQOL in gout is impaired by gout-specific, comorbid, and sociodemographic characteristics, highlighting the importance of comorbidity screening and early urate-lowering therapy. Both gout-specific and generic questionnaires identify the impact of disease-specific features on HRQOL but studies focusing on comorbidity should include generic instruments.

The association between thyroid disorders and incident gout: population-based case-control study

Context

Thyroid hormones influence kidney function and thereby might alter serum urate levels, a major risk factor for gouty arthritis.

Objective

To assess the risk of developing incident gout in association with hypothyroidism or hyperthyroidism.

Design

Retrospective population-based case–control analysis.

Setting

UK-based Clinical Practice Research Datalink, a primary care research database.

Patients

We identified adult patients with a diagnosis of incident gout between 1990 and 2014. We matched one control to each gout case in terms of age, sex, general practice, calendar time, and years of active history in the database.

Main outcome measure

We used conditional logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for developing gout in association with hypo- or hyperthyroidism and adjusted for potential confounders.

Results

The study population encompassed 68,159 incident gout cases, of whom 78.8% were male, and the same number of matched controls. There was no increased risk of gout in patients with hypothyroidism: adjusted OR of gout of 1.12 (95% CI 1.05–1.20) compared with no hypothyroidism. Current short-term treatment of thyroid hormone replacement therapy was associated with an adjusted OR of gout of 1.54 (95% CI 1.24–1.92), compared with no treatment. Neither hyperthyroidism nor current treatment with thyroid suppression therapy was associated with gout (adjusted OR, 1.08 [95% CI 0.95–1.22] and 0.82 [95% CI 0.57–1.17], respectively).

Conclusion

This large observational study does not provide evidence that hypothyroidism or hyperthyroidism, irrespective of treatment, is associated with a clinically relevant increased risk of developing incident gout. There may be an exception among patients with newly diagnosed and treated hypothyroidism.

Cadmium exposure and its association with serum uric acid and hyperuricemia

Few studies have investigated the association between serum uric acid (UA) and cadmium exposure. Our previous study revealed a significantly higher blood cadmium (CdB) level in the Chinese population compared to populations in other countries. To determine whether CdB in Chinese adults is associated with serum UA and hyperuricemia, 2996 participants from the cross-sectional SPECT-China study were recruited. CdB was measured by atomic absorption spectrometry. Hyperuricemia was defined as a serum UA concentration ≥416.4 μmol/L for men and ≥356.9 μmol/L for women. Regression analyses were used to analyze the association of CdB with serum UA and hyperuricemia. We found that the median CdB level was higher in men with hyperuricemia (2.40 μg/L) than in men without hyperuricemia (1.98 μg/L, P < 0.05). A positive relationship between serum UA and CdB was found in Chinese men after adjusting for the estimated glomerular filtration rate (eGFR), current smoking status, diabetes, dyslipidemia, hypertension and body mass index and in participants with eGFR > 60 mL/min per 1.73 m². Further, the odds ratio of hyperuricemia increased with increasing CdB quartiles (P for trend < 0.05) in men. In conclusion, CdB was positively related to the serum UA level and to hyperuricemia in Chinese men but not in Chinese women.

Sex differences in gout characteristics: tailoring care for women and men

Background

To characterize the differences between women and men with gout.

Methods

We analyzed a US national cohort of gout patients cared for by rheumatologists.

Results

Compared with the 1012 men with gout, women with gout (n = 262) were older (71 vs. 61 years, p < 0.001) and had a greater burden of comorbid conditions (p < 0.001 for hypertension, diabetes, renal disease and obesity). Risk factors for gout differed with women more often taking diuretics (p < 0.001), while men more frequently had dietary triggers (p < 0.05).

Conclusions

The profiles of women and men with gout are markedly different, suggesting a need to tailor treatment recommendations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-017-1465-9) contains supplementary material, which is available to authorized users.

The Direct Economic Burden of Gout in an Elderly Canadian Population

Objective.

To estimate the direct healthcare cost and resource use from the public payer perspective between patients with incident gout and matched gout-free patients in Ontario.

Methods.

Patients with incident gout aged ≥ 66 with uninterrupted Ontario Health Insurance Plan (OHIP) coverage in the 1-year baseline period were included in the study. Patients with gout were indexed at first gout diagnosis or prescription over the study period April 1, 2008, to March 31, 2014. Gout-free patients with no gout diagnosis within history were matched (up to 5:1) to each patient with gout. Linked medical records were analyzed until end of study, death, or OHIP ineligibility. Bang and Tsiatis adjusted healthcare costs and resource use were compared using bootstrap p-values and 95% CI.

Results.

A total of 29,894 patients with gout and 148,231 gout-free patients were included in the study. Patients were 56% male, had a median Adjusted Clinical Group healthcare resource use band of moderate morbidity, and had a median age of 75–79 years. Baseline comorbidities were similar between groups except for renal disease. Analyzing 5-year total healthcare costs, patients with gout ($44,297) incurred a significantly higher average healthcare cost compared to gout-free patients ($33,965), for an incremental cost of $10,332 (95% CI $9617–$11,039; p < 0.01). Similar trends were observed in all individual healthcare component cost and use metrics.

Conclusion.

Following onset of gout, patients in Ontario incur significantly greater healthcare costs and resource use compared to matched gout-free patients. Alternative gout management strategies should be investigated to reduce the incremental burden of gout borne by the Ontario healthcare system.

The management of gout in different clinical specialties in Turkey: a patient-based survey

Although gout is potentially curable, the management of this disease is often suboptimal. In this study, we investigated the treatment of gout in Turkey and also compared the management approaches to gout in different clinical specialties. Three hundred and nineteen consecutive patients (mean age 58.60 ± 12.8 years; 44 females, 275 males) were included in this multicenter study. A standardized form was generated to collect data about the patient's first admission to health care, the specialty of the doctor first diagnosed the gout, the treatment options for gout including attack management, patient referral, chronic treatment including medical treatment, and life style modifications. Forty patients were referred to another center without any treatment (12.8 %), and referral rate is most common among the primary care physicians (28.8 %). Colchicine was more commonly used for attack prophylaxis than allopurinol. Ninety-two patients had never been treated with allopurinol (28.8 %). Allopurinol prescription was less common among the primary care physicians and orthopedists, and highest among the rheumatologists. Recommendation of diet and life style modifications was less common among the primary care physicians and orthopedists, and highest among the rheumatologists. The rates of life style modification recommendation and long-term allopurinol prescription were 83.7 and 77.6 %, respectively, among the rheumatologists. Both acute and chronic management of gout is suboptimal in Turkey especially among the primary care physicians and orthopedists. Moreover, chronic treatment is even suboptimal among rheumatologists.