Tophi and frequent gout flares are associated with impairments to quality of life, productivity, and increased healthcare resource use: Results from a cross-sectional survey

Population-specific association between ABCG2 variants and tophaceous disease in people with gout

Background

Tophi contribute to musculoskeletal disability, joint damage and poor health-related quality of life in people with gout. The aim of this study was to examine the role of SLC2A9 and ABCG2 variants in tophaceous disease in people with gout.

Methods

Participants (n = 1778) with gout fulfilling the 1977 American Rheumatism Association (ARA) classification criteria, who were recruited from primary and secondary care, attended a detailed study visit. The presence of palpable tophi was recorded. SLC2A9 rs11942223, ABCG2 rs2231142 and ABCG2 rs10011796 were genotyped. Data were analysed according to tophus status.

Results

Compared to participants without tophi, those with tophi were older, had longer disease duration and higher serum creatinine, and were more likely to be of Māori or Pacific (Polynesian) ancestry. SLC2A9 rs11942223 was not associated with tophi. However, the risk alleles for both ABCG2 single nucleotide polymorphisms (SNPs) were present more frequently in those with tophi (OR (95% CI) 1.24 (1.02–1.51) for rs2231142 and 1.33 (1.01–1.74) for rs10011796, p < 0.05 for both). The effect of rs2231142 was limited to participants of Māori or Pacific ancestry (OR 1.50 (1.14–1.99), p = 0.004), with a significant effect observed in those of Western Polynesian ancestry only (OR 1.71 (1.07–2.72), p = 0.017). The rs10011796 risk allele was strongly associated with tophi in the Western Polynesian group (OR 3.76 (1.61–8.77), p = 0.002), but not in the Eastern Polynesian group (OR 0.87 (0.52–1.46), p = 0.60) nor in the non-Polynesian group (OR 1.16 (0.81–1.66), p = 0.32). The ABCG2 associations persisted in the Western Polynesian group after adjusting for serum urate, creatinine, and disease duration, and when including both ABCG2 variants in the regression models.

Conclusions

Variation in ABCG2 function may play a role in the development of tophaceous disease in some populations with high prevalence of severe gout.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1254-8) contains supplementary material, which is available to authorized users.

Serum uric acid levels and the risk of flares among gout patients in a US managed care setting

OBJECTIVE

Serum uric acid (sUA) levels are causally associated with the risk of gout flares. Our aim was to assess the magnitude of the association and time to first flare among patients in a managed care setting.

RESEARCH DESIGN AND METHODS

We conducted a retrospective cohort study using administrative claims data from a large US health plan. Patients were required to have evidence of gout based on medical and pharmacy claims between January 2009 and April 2012. The 12 months prior to the index gout claim were used to assess baseline sUA levels; risk of gout flares, stratified by baseline sUA levels, was examined for 2 years post-index. Risk of flare was modeled with Cox proportional hazards; time to first flare was assessed by Kaplan-Meier.

RESULTS

We identified 18,008 patients with gout and available baseline SUA levels (mg/dL). The hazard ratios for the risk of gout flares compared with sUA <5.0 were: 1.17 for sUA 5.0 to <6.0; 1.69 for sUA 6.0 to <7.0; 2.16 for sUA 7.0 to <8.0; 2.87 for sUA 8.0 to <9.0; and 3.85 for sUA ≥9.0 (all p < .001 except for sUA 5.0 to <6.0 cohort). The time to first flare was shorter for cohorts with higher baseline sUA levels.

CONCLUSION

These findings confirm that higher sUA levels are associated with an increased risk of gout flares in a dose-response manner over 2 years. This data supports the need to treat to sUA target levels as recommended by recent gout care guidelines. Claims-based algorithms were used to identify gout flares; although this would not be expected to influence estimates of risk by sUA level, there may have been over- or under-estimation of the incidence of flares.

Association between Gout and Erectile Dysfunction: A Systematic Review and Meta-Analysis

Background

The aim of this systematic review and meta-analysis was to assess the possible association between gout and erectile dysfunction (ED).

Methods

Studies were identified by extensively searching EMBASE, Pubmed, CENTRAL and ISI Web of Science. Four electronic databases were searched from their inception date to the latest issue (March 2016), without language restriction. Each reviewer screened articles independently and was blinded to the findings of the other reviewer. Data was extracted in adherence to the predetermined data collection form and meta-analysis was conducted via RevMan 5.3.

Results

Five studies involving 56465 patients (mean age: 49.11 years) with gout and 155636 non-gout subjects (mean age: 48.76 years) were selected. The combination of unadjusted odds ratio (OR) showed that patients with gout were 1.44 times more likely to be diagnosed with ED when compared with control (95% confidence interval (95%CI) 1.20, 1.72). After adjustment for age and comorbidities, the heightened risk to develop ED was still present (1.18, 95%CI 1.02, 1.38). Subgroup-analysis by age showed statistically significant association of gout and ED in all age groups. However, evidence supporting a causal effect of gout on ED was insufficient.

Conclusion

The findings of this review indicated a positive association of gout and ED, but this work is hampered by the heterogeneity among included studies, to some extent. Future studies with larger community-based homogeneous population and randomized controlled trials aimed to evaluate the effect of gout treatment on ED associated outcomes are needed at this point.

Nocturia Work Productivity and Activity Impairment Compared with Other Common Chronic Diseases

OBJECTIVES

The International Continence Society defines nocturia as the need to void one or more times during the night, with each of the voids preceded and followed by sleep. The chronic sleep disturbance and sleep deprivation experienced by patients with nocturia affects quality of life, compromising both mental and physical well-being. This paper aims to characterise the burden of nocturia by comparing published data from patients with nocturia with data from patients with any of 12 other common chronic conditions, specifically focusing on its impact on work productivity and activity impairment, as measured by the instrument of the same name (WPAI).

METHODS

A systematic literature review of multiple data sources identified evaluable studies for inclusion in the analysis. Study eligibility criteria included use of the WPAI instrument in patients with one of a predefined list of chronic conditions. We assessed the quality of each included study using the Newcastle-Ottawa scale and extracted basic study information, work and activity impairment data. To assess how work and activity impairment from nocturia compares with impairment from other common chronic diseases, we conducted two data syntheses (pooled and unpooled).

RESULTS

The number of evaluable studies and the range of overall work productivity impairment reported, respectively, were as follows: nocturia (3; 14-39 %), overactive bladder (5; 11-41 %), irritable bowel syndrome/constipation (14; 21-51 %), gastroesophageal reflux disease (GERD) (13; 6-42 %), asthma/allergies (11; 6-40 %), chronic obstructive pulmonary disease (COPD) (7; 19-42 %), sleep problems (3; 12-37 %), arthritis (13; 21-69 %), pain (9; 29-64 %), depression (4; 15-43 %) and gout (2; 20-37 %).

CONCLUSIONS

The overall work productivity impairment as a result of nocturia is substantial and was found to be similar to impairment observed as a result of several other more frequently researched common chronic diseases. Greater awareness of the burden of nocturia, a highly bothersome and prevalent condition, will help policy makers and healthcare decision makers provide appropriate management of nocturia.

Update on the Clinical Effect of Acupuncture Therapy in Patients with Gouty Arthritis: Systematic Review and Meta-Analysis

Objective. The aim of this study is to evaluate the clinical efficacy and safety of acupuncture therapy in the treatment of acute gouty arthritis. Methods. A literature search of PubMed, EMBASE, ISI Web of Science, CENTRAL, and CNKI was conducted from the inception date of each database up to October 2015. Two investigators screened each article independently and were blinded to the findings of the other reviewer. Data was extracted according to the predetermined collection form. Meta-analysis was performed. Results. We analyzed data from 28 RCTs involving 2237 patients with gouty arthritis. Compared with conventional pharmacological treatments acupuncture was more effective in rendering patients free from symptoms after 24 hours, lowering serum urate, alleviating pain associated with gouty arthritis, and decreasing the ESR; regarding CRP, no statistically significant difference was found. In addition, the frequency of adverse events in acupuncture treatment was lower than that in control group. Conclusion. Based on the findings of our study, we cautiously suggest that acupuncture is an effective and safe therapy for patients with gouty arthritis. However, the potential beneficial effect of acupuncture might be overstated due to the methodological deficiency of included studies. High quality RCTs with larger scale are encouraged.

Racial differences in health-related quality of life and functional ability in patients with gout

OBJECTIVE

To compare the health-related quality of life (HRQOL) and the functional ability by race in patients with gout.

METHODS

In a 9-month prospective cohort multicentre study, patients with gout self-reported race, dichotomized as Caucasian or African American (others excluded). We calculated HRQOL/function scores adjusted for age, study site and college education for Short Form-36 (SF-36; generic HRQOL), Gout Impact Scale (GIS; disease-specific HRQOL) and HAQ-disability index (HAQ-DI; functional ability). Longitudinally adjusted scores were computed using multivariable mixed-effect regression models with a random patient effect and fixed sequential visit effect (3-monthly visits).

RESULTS

Compared with Caucasians (n = 107), African Americans (n = 60) with gout were younger (61.1 vs 67.3 years) and had higher median baseline serum urate (9.0 vs 7.9 mg/dl) (P < 0.01). African Americans with gout had worse HRQOL scores on three SF-36 domains, the mental component summary (MCS) and two of the five GIS scales than Caucasians [mean (se); P ⩽ 0.02 for all]: SF-36 mental health, 39.7 (1.1) vs 45.2 (0.9); SF-36 role emotional, 42.1 (4.2) vs 51.4 (4.2); SF-36 social functioning, 36.0 (1.1) vs 40.0 (0.9) (P = 0.04); SF-36 MCS, 43.2 (3.1) vs 50.0 (3.2); GIS unmet treatment need, 37.6 (1.6) vs 31.5 (1.4); and GIS concern during attacks, 53.3 (3.7) vs 47.4 (3.7). Differences between the respective HAQ-DI total scores were not statistically significant; 0.98 (0.1) vs 0.80 (1.0) (P = 0.11). Racial differences in SF-36 mental health, role emotional and MCS scales exceeded, and for HAQ-DI approached, the minimal clinically important difference thresholds.

CONCLUSIONS

African Americans with gout have significantly worse HRQOL compared with Caucasians. Further research is necessary in the form of studies targeted at African Americans on how best to improve these outcomes.

Gout

Gout is a chronic disease of deposition of monosodium urate crystals, which form in the presence of increased urate concentrations. Although environmental factors contribute to hyperuricaemia, renal and gut excretion of urate is central to regulation of serum urate, and genetic factors are important. Activation of the NLRP3 inflammasome and release of interleukin 1β have key roles in initiation of acute gout flares. A "treat to target serum urate" approach is essential for effective gout management; long-term lowering of serum urate to less than 360 μmol/L leads to crystal dissolution and ultimately to suppression of flares. An allopurinol dose-escalation strategy is frequently effective for achieving treatment targets, and several new urate-lowering drugs are also available. Worldwide, rates of initiation and continuation of urate-lowering therapy are very low, and, consequently, achievement of serum urate targets is infrequent. Strategies to improve quality of gout care are needed.

Disease Control, Health Resource Use, Healthcare Costs, and Predictors in Gout Patients in the United States, the United Kingdom, Germany, and France: A Retrospective Analysis

INTRODUCTION

The present study aimed to assess disease control, health resource utilization (HRU), and healthcare costs, and their predictors in gout patients across the USA, UK, Germany, and France.

METHODS

Data were extracted from the PharMetrics Plus (USA), Clinical Practice Research Datalink-Hospital Episode Statistics (UK), and Disease Analyzer databases (Germany and France) for adult gout patients over a 3-year period: 2009-2011 (all dates +1 year for France). Patients had "prevalent established gout" (i.e., were treated with urate-lowering therapy [ULT] or eligible for ULT based on American College of Rheumatology guidelines) in the preindex panel-year, with January 1 of the second study year as the study index date. Assessments of disease control (uncontrolled gout definition: ≥1 serum urate (sUA) elevation or ≥2 flares; analysis limited to the subpopulation with sUA) data, HRU, and costs were in the second post-index panel-year, while potential predictors (demographics and gout treatment characteristics) were identified in the first post-index panel-year.

RESULTS

Treatment rates were high (>70% with chronic urate-lowering treatment in all countries but France), while between 31.3% (France) and 62.9% (USA) of patients remained uncontrolled. Predictors of control included female gender and high adherence. In Germany, the UK, and France, lack of disease control predicted increased gout-attributed costs and increased HRU, both gout-attributed (also in the USA) and non-gout-attributed.

CONCLUSION

Gout management remains suboptimal, as many patients remain uncontrolled despite using urate-lowering treatment. Effective and convenient treatment options are needed to improve disease control and minimize additional HRU and costs.

FUNDING

AstraZeneca.

The Human and Economic Burden of Difficult-to-Treat Gouty Arthritis

Gouty arthritis, one of the most painful and common forms of adult arthritis, is caused by monosodium urate crystal deposits in joints, most often in the lower extremities. Crystals trigger an inflammatory response leading to acute flares characterized by a rapid onset of pain, warmth, swelling, and redness in involved joints. Over time, continued monosodium urate crystal deposits and inflammation can lead to chronic tophaceous gout that result in bone erosion, progressing to joint destruction and significant disability. The goal of therapy in an acute gout flare is prompt and safe termination of pain and inflammation. Acute gouty arthritis is usually treated with nonsteroidal anti-inflammatory drugs, colchicine, or corticosteroids. However, for a growing number of patients, current standard treatments are ineffective or are contraindicated, largely due to the presence of comorbidities. Gouty arthritis can have a major negative impact of health-related quality of life, especially in patients with difficult-to-treat disease, as revealed by recent studies comparing health-related quality of life with that of the general population. Additionally, gouty arthritis also constitutes an important economic burden through absence from work and medical costs. This burden is even greater in patients with difficult-to-treat disease.

Cost-effectiveness analysis of febuxostat in patients with gout in Spain

Objectives Cost-effectiveness of febuxostat compared with allopurinol in the treatment of hyperuricemia in patients with gout. Methods Costs, clinical outcomes, and QALYs were estimated using a Markov model. Febuxostat 80 mg and 120 mg sequentially, used as first line and second line therapy, was compared with allopurinol 300 mg. Patients switched to the next treatment in the sequence according to a dichotomous response vs no response (target serum urate level < 6 mg/dl outcome) after 3 months of active treatment. A 3% discount rate and 5-year time horizon were applied.

PERSPECTIVE

National Health System. Results The addition of febuxostat to any therapeutic strategy was an efficient option, with incremental cost-effectiveness ratios (ICER) compared with allopurinol 300 mg ranging from €5268-€9737. Conclusions Febuxostat is a cost-effective treatment in Spain for the management of hyperuricemia in gout patients, with ICERs far below accepted Spanish efficiency thresholds (30 000€/QALY).

Physical Function, Hyperuricemia, and Gout in Older Adults

OBJECTIVE

Gout prevalence is high in older adults and those affected are at risk of physical disability, yet it is unclear whether they have worse physical function.

METHODS

We studied gout, hyperuricemia, and physical function in 5,819 older adults (age ≥65 years) attending the 2011-2013 Atherosclerosis Risk in Communities Study visit, a prospective US population-based cohort. Differences in lower extremity function (Short Physical Performance Battery [SPPB] and 4-meter walking speed) and upper extremity function (grip strength) by gout status and by hyperuricemia prevalence were estimated in adjusted ordinal logistic regression (SPPB) and linear regression (walking speed and grip strength) models. Lower scores or times signify worse function. The prevalence of poor physical performance (first quartile) by gout and hyperuricemia was estimated using adjusted modified Poisson regression.

RESULTS

Ten percent of participants reported a history of gout and 21% had hyperuricemia. There was no difference in grip strength by history of gout (P = 0.77). Participants with gout performed worse on the SPPB test; they had 0.77 times (95% confidence interval [95% CI] 0.65, 0.90, P = 0.001) the prevalence odds of a 1-unit increase in SPPB score and were 1.18 times (95% CI 1.07, 1.32, P = 0.002) more likely to have poor SPPB performance. Participants with a history of gout had slower walking speed (mean difference -0.03; 95% CI -0.05, -0.01, P < 0.001) and were 1.19 times (95% CI 1.06, 1.34, P = 0.003) more likely to have poor walking speed. Similarly, SPPB score and walking speed, but not grip strength, were worse in participants with hyperuricemia.

CONCLUSION

Older adults with gout and hyperuricemia are more likely to have worse lower extremity, but not upper extremity, function.

Patients with Gout Treated with Conventional Urate-lowering Therapy: Association with Disease Control, Health-related Quality of Life, and Work Productivity

OBJECTIVE

Implications of inadequate gout control were assessed through health-related quality of life (HRQOL) and work productivity of patients with gout adequately controlled while taking conventional urate-lowering therapy (ULT) for ≥ 3 months vs those whose gout was inadequately controlled.

METHODS

Retrospective data were drawn from the Adelphi Disease Specific Programme (DSP), a cross-sectional survey of patients with gout in France, Germany, the United Kingdom, and the United States. Patients completed these questionnaires: EQ-5D (3L), Patient Reported Outcomes Measurement Information System (PROMIS) Health Assessment Questionnaire (HAQ), and Work Productivity and Activity Impairment. Inadequate control was defined as the most recent serum uric acid (SUA) level > 6 mg/dl (> 360 µmol/l) or ≥ 2 flares in the last 12 months; adequate control as SUA level ≤ 6 mg/dl (≤ 360 µmol/l) and 0 flares. Appropriate statistical tests were used to assess differences between groups.

RESULTS

There were 836 (69%) inadequately and 368 (31%) adequately controlled gout cases. Mean age was 61 and 63 years and duration of current ULT was 32 and 57 months, respectively. Patients experiencing inadequate control reported significantly worse functioning and HRQOL, as measured by the EQ-5D (0.790 vs 0.877; difference: -0.087; p < 0.001) and PROMIS HAQ (13.21 vs 6.91; difference: 6.30; p < 0.001) scales. Productivity was also more impaired (work time missed: 4.5% vs 1.3%; impairment while working: 19.1% vs 5.2%; overall work impairment: 20.4% vs 5.6%; activity impairment: 20.3% vs 5.3%; all p < 0.001).

CONCLUSION

Less than one-third of patients had gout that was adequately controlled. Those experiencing inadequately controlled gout reported significantly worse functioning, quality of life, and work productivity. Gout treatment strategies to improve disease control may lead to improvements in HRQOL and productivity.

A cross-sectional internet-based patient survey of the management strategies for gout

BACKGROUND

Almost half of the patients with gout are not prescribed urate-lowering therapy (ULT) by their health care provider and >50 % use complementary and alternative therapies. Diet modification is popular among gout patients due to known associations of certain foods with gout flares. The interplay of the use of dietary supplements, diet modification, and ULT adherence in gout patients is not known. Despite the recent interest in diet and supplements, there are limited data on their use. Our objective was to assess ULT use and adherence and patient preference for non-pharmacological interventions by patients with gout, using a cross-sectional survey.

METHODS

People who self-reported physician-diagnosed gout during their visit to a gout website ( http://gouteducation.org ) were invited to participate in a brief anonymous cross-sectional Internet survey between 08/11/2014 to 04/14/2015 about the management of their gout. The survey queried ULT prescription, ULT adherence, the use of non-pharmacological interventions (cherry extract, diet modification) and the likelihood of making a lifelong diet modification for gout management.

RESULTS

A total of 499 respondents with a mean age 56.3 years were included; 74% were males and 74% were White. Of these, 57% (285/499) participants were prescribed a ULT for gout, of whom 88% (251/285) were currently taking ULT. Of those using ULT, 78% (97/251) reported ULT adherence >80%. Gender, race, and age were not significantly associated with the likelihood of receiving a ULT prescription or ULT adherence >80%. Fifty-six percent of patients with gout preferred ULT as a lifelong treatment for gout, 24% preferred cherry extract and 16% preferred diet modification (4% preferred none). Men had significantly lower odds of preferring ULT as the lifelong treatment choice for gout vs. other choices (p = 0.03). We found that 38.3% participants were highly motivated to make a lifelong dietary modification to improve their gout (score of 9-10 on a 0-10 likelihood scale). Older age was significantly associated with high level of willingness to modify diet (p = 0.02).

CONCLUSION

We found that only 57% of gout patients reported being prescribed ULT. 40% of gout patients preferred non- pharmacological interventions such as cherry extract and diet modification for gout management. The latter finding requires further investigation.

Treatment of tophaceous gout: When medication is not enough

OBJECTIVES

To review the literature concerning surgical intervention of tophaeceous gout and propose clinical circumstances for when it may be considered.

INTRODUCTION

Tophi develop in approximately 12-35% of patients with gout. Tophaceous disease is usually preventable given the availability of effective urate lowering therapies (ULT) including allopurinol, febuxostat, probenecid, lesinurad, and pegloticase. Despite medical therapy, there remains a subset of patients who develop significant complications of tophi including infection, ulceration, and entrapment neuropathy. Tophi in close proximity to joints can cause joint instability, severely limited range of motion, and significant functional impairment. For the rare circumstance when a tophus is causing an urgent complication or if a patient has a contraindication to all available ULTs, surgery may be an appropriate option. This review summarizes the published experience with surgical interventions for tophaceous gout and offers recommendations for its consideration.

METHODS

Using Medline and Google Scholar, all available series of surgery for tophaceous gout were reviewed.

RESULTS

Overall, 7 published surgical series were identified. In all, 6 of these 7 series were published between 2002 and 2014. The reported outcomes of surgical interventions for tophaceous gout were generally positive without major post-surgical complications.

CONCLUSION

Although medical therapy with ULTs should be the first-line approach to tophaceous gout, surgery should be considered for the rare patient with impending or severe, debilitating complications including infections, entrapment neuropathy or those at risk for permanent joint destruction. In these selected clinical circumstances, surgical intervention for tophaceous gout may be appropriate.

Management of gout in the real world: current practice versus guideline recommendations

OBJECTIVES

Gout is a chronic, extremely painful disease that is potentially curable when treated effectively. Unfortunately approximately one-half of patients with gout are inadequately controlled.

METHODS

We surveyed 315 primary care physicians in the United States and Europe to investigate current practice in the real world, as distinct from recommendations in guidelines.

RESULTS

Our survey on 1657 patients found that regular testing of serum uric acid, in conformity with the guidelines, was conducted by approximately 50% of physicians. Advice to patients on diet and lifestyle was less well implemented, and identification of overweight/obese patients was inconsistent.

CONCLUSION

Improvements in practice by physicians would include comprehensive assessment of the patient, adoption of regular monitoring during treatment, and the provision of patient education on adherence and lifestyle.

Hyperuricaemia with deposition: latest evidence and therapeutic approach

This article reviews recent evidence on urate deposition and the opportunity for a therapeutic approach. We reviewed Pubmed 2013-2015 literature using the search terms 'deposition' with 'hyperuricaemia', 'gout', 'ultrasonography', 'DECT' (dual-energy computed tomography), 'radiography', 'CT'(computed tomography), 'MRI' (magnetic resonance imaging), or 'cardiovascular', in addition to a digital bibliographic library compiled by the authors with 2072 papers on hyperuricaemia and gout. Relevant papers on the topic were selected. Recent evidence, mostly based on imaging studies, showed a continuum from hyperuricaemia to deposition and clinical manifestations. Chronic inflammation and structural damage may be present even in asymptomatic patients with crystal-proved deposition. The impact of early intervention in patients with asymptomatic deposition either on vascular outcomes or further structural joint damage has not been demonstrated yet. In conclusion, a worldwide definition of gout is still lacking, stages from hyperuricaemia to clinical gout not being definitively defined. Although there is increasing interest on the impact of early deposits on joint damage and cardiovascular outcomes, robust evidence is still lacking to fully support interventions.

The gouty tophus: a review

The tophus is the cardinal feature of advanced gout. This review summarises recent research into the biology, impact and treatment of tophaceous gout. Microscopically, tophi are chronic foreign body granuloma-like structures containing collections of monosodium urate (MSU) crystals surrounded by inflammatory cells and connective tissue. Extracellular trap formation mediated by neutrophil interactions with MSU crystals may be a central checkpoint in tophus formation. Gouty tophi impact on many aspects of health-related quality of life. Tophi are also implicated in the development of structural joint damage and increased mortality risk in people with gout. Effective treatment of tophaceous gout requires long-term urate-lowering therapy, ideally to achieve a serum urate concentration of <5 mg/dL (300 μmol/L). Recent advances in gout therapeutics have expanded urate-lowering therapy options for patients with severe tophaceous disease to allow faster regression of tophi, improved health-related quality of life and, potentially, improved structural outcomes.

A world of hurt: failure to achieve treatment goals in patients with gout requires a paradigm shift

BACKGROUND

Gout continues to be underdiagnosed and poorly managed despite the potential for cure. US and European management guidelines recommend treating to target serum urate (sUA) levels of <6 mg/dL (or <5 mg/dL to durably improve severe symptoms), with use of regular sUA monitoring, but studies suggest relatively poor adherence to these recommendations. This study investigates the real-world state of gout management in the United States by describing the characteristics of a large patient population treated in primary care and rheumatology settings.

METHODS

A retrospective chart audit, conducted among 124 primary care physicians and 125 rheumatologists, included 1245 patients with gout. Physicians completed structured case report forms capturing 12 months of sUA laboratory values, flare counts, comorbidities, types and doses of treatment, treatment duration, diagnosis date, physician specialty and socio-demographic factors. Focusing on the xanthine oxidase inhibitors (n = 858), descriptive statistics and multivariate models characterized relationships between patient characteristics, disease control, and treatment.

RESULTS

Only 83 (11%) patients achieved disease control, defined as a 12-month average sUA ≤6 mg/dL, no flares, and no tophi. Patients with greatest disease severity (defined as sUA >6 mg/dL, ≥2 flares per year, and tophi) were more likely to have kidney disease and other comorbidities. In a multivariate model, predictors of more severe gout were rheumatologist (vs primary care) management, febuxostat (vs allopurinol) use and presence of comorbid conditions.

CONCLUSION

Our findings confirm the inadequacy of gout management in the real-world setting. Regular monitoring, including sUA measurement as recommended in guidelines, is important to assess gout control. Our analyses also demonstrate that patients with more severe gout are more likely to have comorbid conditions, be treated by a specialist and use newer therapies.

Barriers to Care in Gout: From Prescriber to Patient

OBJECTIVE

To explore the understanding of gout and its management by patients and general practitioners (GP), and to identify barriers to optimal gout care.

METHODS

Semistructured interviews were conducted with 15 GP and 22 patients in Sydney, Australia. Discussions were focused on medication adherence, experiences with gout, and education and perceptions around interventions for gout. Interviews were audio recorded, transcribed verbatim, and analyzed for themes using an analytical framework.

RESULTS

Adherence to urate-lowering medications was identified as problematic by GP, but less so by patients with gout. However, patients had little appreciation of the risk of acute attacks related to variable adherence. Patients felt stigmatized that their gout diagnosis was predominantly related to perceptions that alcohol and dietary excess were causal. Patients felt they did not have enough education about gout and how to manage it. A manifestation of this was that uric acid concentrations were infrequently measured. GP were concerned that they did not know enough about managing gout and most were not familiar with current guidelines for management. For example and importantly, the strategies for reducing the risk of acute attacks when commencing urate-lowering therapy (ULT) were not well appreciated by GP or patients.

CONCLUSION

Patients and GP wished to know more about gout and its management. Greater success in establishing and maintaining ULT will require further and better education to substantially benefit patients. Also, given the prevalence, and personal and societal significance of gout, innovative approaches to transforming the management of this eminently treatable disease are needed.

Health and Utilities in Patients With Gout Under the Care of a Rheumatologist

OBJECTIVE

To compare limitations in health between Dutch patients with gout and the general population and to determine factors influencing societal and patient values for health as assessed with different utility approaches.

METHODS

A cross-sectional study was done among 110 patients with gout under the care of a rheumatologist, with patients completing the EuroQol 5-domain instrument (EQ-5D), the EQ-5D visual analog scale (EQ-5D VAS), and the Short Form 6-dimensions health survey (SF-6D). Scores on EQ-5D domains were compared with age- and sex-matched general population data. Agreement between utility measures was assessed using the intraclass correlation coefficient (ICC). Mixture modeling was used to assess factors associated with the different approaches to assess utility.

RESULTS

Compared to the general population, gout patients reported more limitations in mobility (66% versus 12%), self-care (24% versus 8%), daily activities (49% versus 24%), and pain (76% versus 45%), but equal anxiety/depressive symptoms (18% versus 19%). For patients with gout, utilities were reduced: the mean, median, and interquartile range, respectively, were 0.74, 0.81, and 0.69-0.84 for EQ-5D, 0.69, 0.67, and 0.59-0.81 for SF-6D, and 66, 70, and 57-77 for EQ-5D VAS. ICC agreement between each pair of utilities was only moderate (0.52-0.59). Only minor differences were seen in the type of variables associated with each utility approach, with worse Health Assessment Questionnaire scores, cardiovascular disease (CVD), gout concern, and gout pain consistently associated with lower utility. The strength of contribution of these variables, however, differed among the 3 approaches.

CONCLUSION

Patients with gout experience substantially impaired health compared to the general population. Although absolute values of utility varied between instruments and perspectives, functional disability, CVD, and higher gout impact contributed to utility independently of which instrument was used.

A Systematic Review of the Economic and Humanistic Burden of Gout

BACKGROUND

Gout is a chronic and inflammatory form of arthritis that is often overlooked despite the associated pain caused by acute flares and associated joint damage caused by the development of debilitating tophi. The increasing burden of gout, due to an aging population and the increased prevalence of known risk factors for hyperuricaemia, means that there is a continued need for new and effective urate-lowering treatments. The evaluation of these treatments will require a comprehensive and comparative evidence base describing the economic and humanistic burden of gout, taken from the perspective of patients, the healthcare system, and wider society.

OBJECTIVE

The objective of this study is to review and summarise the current evidence of the disease burden related to chronic gout, assessed in terms of both cost and health-related quality of life (HRQL), and to identify key factors correlated with an increased burden. The overall aim is to support the economic evaluation of new treatments for gout, and to highlight key data gaps that may need further study and exploration.

METHODS

Relevant literature dating from January 2000 to July 2014 was sourced through searches of the MEDLINE database via PubMed and The Cochrane Library. Articles published in English and reporting either the economic burden (cost) or the humanistic burden (HRQL/utility) of gout were identified, and key data were extracted and summarised, with key themes and data gaps identified and discussed.

RESULTS

Of the 323 studies identified, 39 met the inclusion criteria, of which 17 and 26 were relevant to the economic and humanistic burden, respectively. The economic burden of gout varied according to numerous factors, most notably serum urate acid levels and number of flares and tophi, resulting in higher healthcare resource use most often attributed to hospitalisation and inpatient stay. The incremental direct cost of gout has been suggested in the range of US$3165 to US$5515 (2004 and 2005 values, respectively) climbing to US$10,222 to US$21,467 (2008 values) per annum where patients are experiencing regular acute flares and have tophi present. The humanistic burden of gout was largely due to physical disability and pain resulting from chronic clinical manifestations. Short Form 6 dimensions (SF-6D) assessed utility weights are estimated at 0.53 for a patient with severe gout (≥3 flares/year and tophi) compared with 0.73 for an asymptomatic gout patient with serum acid levels <6 mg/dl.

CONCLUSIONS

The evidence confirms that gout has a growing overall prevalence and represents a significant burden in terms of both direct healthcare cost and HRQL outcomes. In light of this, effective urate-lowering treatments are likely to be valued if they can be clearly demonstrated to be both clinically effective and cost effective. Published data to support healthcare decision making in non-US countries with regards to treatments for gout are currently limited, which is a key limitation of the current evidence base. More research is also required to extend our understanding of the impact of gout on indirect costs, and a need also exists to develop a more comprehensive set of comparative HRQL utility assessments.

"You want to get on with the rest of your life": a qualitative study of health-related quality of life in gout

The objective of the study is to examine the impact of gout and its treatments on health-related quality of life (HRQOL) using focus group interviews. From the baseline phase of a cohort study of HRQOL in gout, 17 participants (15 males, mean age 71 years) with varying attack frequency and treatment with and without allopurinol participated in one of four focus group interviews. All interviews were audio-recorded and transcribed verbatim. Data was analysed thematically. Physical and psychosocial HRQOL in gout was affected by characteristics of acute gout (particularly the unpredictable nature of attacks, location of joint involved in an attack, pain and modifications in lifestyle), lack of understanding of gout by others (association with unhealthy lifestyle, symptoms ridiculed as non-severe and non-serious) as well as participants (not considered a disease) and the lack of information provided by physicians (about causes and pharmacological as well as non-pharmacological treatments of gout). Participants emphasised the impact of acute attacks of gout and prioritised dietary modifications and treatment of acute attacks over long-term urate-lowering therapy. Characteristics of acute gout, lack of understanding and information about gout and its treatments perpetuate poor HRQOL. HRQOL (maintenance of usual diet and reduced frequency of attacks) was associated with urate-lowering treatment. Better patient, public and practitioner education about gout being a chronic condition associated with co-morbidities and poor HRQOL may improve understanding and long-term treatment of gout.

Patient and clinical characteristics associated with gout flares in an integrated healthcare system

Gout flares have been challenging to identify in retrospective databases due to gout flares not being well documented by diagnosis codes, making it difficult to conduct accurate database studies. Previous studies have used different algorithms, and in this study, we used a computer-based method to identify gout flares. The objectives of this study were to identify gout flares in gout patients newly initiated on urate-lowering therapy and evaluate factors associated with a patient experiencing gout flares after starting drug treatment. This was a retrospective cohort study identifying gout patients newly initiated on a urate-lowering therapy (ULT) during the study time period of January 1, 2007-December 31, 2010. The index date was the first dispensed ULT prescription during the study time period. Patients had to be ≥18 years of age on index date, have no history of prior ULT prescription during 12 months before index date, and were required to have 12 months of continuous membership with drug benefit during pre-/post-index. Electronic chart notes were reviewed to identify gout flares; these reviews helped create a validated computer-based method to further identify patients with gout flares and were categorized into 0 gout flares, 1-2 gout flares, and ≥3 gout flares during the 12 months post-index period. Multivariable logistic regression was used to examine patient and clinical factors associated with gout flares during the 12-month follow-up period. There were 8905 patients identified as the final cohort and 68 % of these patients had one or more gout flares during the 12-month follow-up: 2797 patients (31 %) had 0 gout flares, 4836 (54 %) had 1-2 gout flares, and 1272 patients (14 %) had ≥3 gout flares. Using a multivariate regression analyses, factors independently associated with 1-2 gout flares and ≥3 gout flares versus no gout flares were similar, however, with slight differences, such as younger patients were more likely to have 1-2 gout flares and patients ≥65 years of age had ≥3 gout flares. Factors such as male gender, not attaining sUA goal, having ≥3 comorbidities, diuretics use, no changes in initial ULT dose, and not adhering to ULT all were associated with gout flares versus no gout flares. Using a new method to identify gout flares, we had the opportunity to compare our findings with the previous studies. Our study findings echo other previous studies where older patients, male, diuretics, having a greater number of comorbidities, and non-adherence are more likely to have more gout flares during the first year of newly initiating ULT. There is an unmet need for patients with gout to be educated and managed more closely, especially during the first year.

Health-related quality of life and treatment satisfaction in patients with gout: results from a cross-sectional study in a managed care setting

BACKGROUND

Patient satisfaction with treatment directly impacts adherence to medication.

OBJECTIVE

The objective was to assess and compare treatment satisfaction with the Treatment Satisfaction Questionnaire for Medication (TSQM), gout-specific health-related quality of life (HRQoL) with the Gout Impact Scale (GIS), and generic HRQoL with the SF-12v2(®) Health Survey (SF-12) in patients with gout in a real-world practice setting.

METHODS

This cross-sectional mail survey included gout patients enrolled in a large commercial health plan in the US. Patients were ≥18 years with self-reported gout diagnosis, who filled ≥1 prescription for febuxostat during April 26, 2012 to July 26, 2012 and were not taking any other urate-lowering therapies. The survey included the TSQM version II (TSQM vII, score 0-100, higher scores indicate better satisfaction), GIS (score 0-100, higher scores indicate worse condition), and SF-12 (physical component summary and mental component summary). Patients were stratified by self-report of currently experiencing a gout attack or not to assess the discriminant ability of the questionnaires.

RESULTS

A total of 257 patients were included in the analysis (mean age, 54.9 years; 87% male). Patients with current gout attack (n=29, 11%) had worse scores than those without gout attack on most instrument scales. Mean differences between current attack and no current attack for the TSQM domains were: -20.6, effectiveness; -10.6, side effects; -12.1, global satisfaction (all P<0.05); and -6.1, convenience (NS). For the GIS, mean differences were: 30.5, gout overall concern; 14.6, gout medication side effects; 22.7, unmet gout treatment needs; 11.5, gout concern during attack (all P<0.05); and 7.9, well-being during attack (NS). Mean difference in SF-12 was -6.6 for physical component summary (P<0.05) and -2.9 for mental component summary (NS). Correlations between several TSQM and GIS scales were moderate.

CONCLUSION

The TSQM and GIS were complementary in evaluating the impact of gout flare on treatment satisfaction and HRQoL. Correlations between the two instruments supported the relationship between treatment satisfaction and HRQoL.

Gout: A clinical overview and its association with cardiovascular diseases

Gout is a common disease caused by the deposition of monosodium urate (MSU) crystals in patients with hyperuricemia, and characterized by very painful recurrent acute attacks of arthritis. The gold standard for diagnosing gout is the identification of MSU crystals in synovial fluid by polarization light microscopy. Arthritis attacks can be treated with anti-inflammatory medications, such as non-steroidal anti-inflammatory drugs, colchicine, oral prednisone, or intra-articular or intramuscular glucocorticoids. To prevent gout uric acid lowering therapy with for example allopurinol can be prescribed. When gout is adequately treated, the prognosis is good. Unfortunately, the management of gout patients is often insufficient. Gout is associated with dietary factors, the use of diuretics, and several genetic factors. Comorbidities as hypertension, chronic kidney disease, cardiovascular diseases, the metabolic syndrome, diabetes, obesity, hyperlipidemia, and early menopause are associated with a higher prevalence of gout. Xanthine oxidase and chronic systemic inflammation seem to play an important role in the pathophysiology of the association between gout and cardiovascular diseases. To prevent cardiovascular diseases gout patients must be early screened for cardiovascular risk factors.

An appraisal of the 2012 American College of Rheumatology Guidelines for the Management of Gout

PURPOSE OF REVIEW

Appraisal of the 2012 American College of Rheumatology (ACR) Guidelines for the Management of Gout.

RECENT FINDINGS

The ACRs first clinical practice guidelines for the management of gout focus on recommendations for nonpharmacologic and pharmacologic approaches to hyperuricaemia and the treatment and prophylaxis of acute gouty arthritis. The RAND/UCLA appropriateness methodology employed assessed risks and benefits of alternative treatments for efficacy, safety and quality but not for cost-effectiveness. Novel recommendations include the use of either allopurinol or febuxostat for first-line urate-lowering drug therapy (ULT), screening for HLA-B*5801 prior to initiation of allopurinol in Asians at relatively high risk for allopurinol hypersensitivity, and the use of pegloticase for patients with severe, symptomatic, tophaceous gout refractory to, or intolerant of, appropriately dosed ULTs. Appraisal and comparison with other guidelines using Guidelines International Network and Appraisal of Guidelines, Research and Evaluation (AGREE II) criteria showed good scores for scope and purpose, stakeholder involvement, rigour of development, clarity of presentation, editorial independence and, overall quality, but not for applicability.

SUMMARY

The ACR guidelines provide comprehensive, up-to-date, good-quality, evidence-based, expert consensus recommendations for the management of gout in clinical practice but score poorly for applicability. To improve the management of gout in the community a summary of key recommendations, criteria for audit and standards of care are now required.

Rilonacept for Gout Flare Prevention in Patients Receiving Uric Acid-lowering Therapy: Results of RESURGE, a Phase III, International Safety Study

Objective.

To evaluate the safety and efficacy of once-weekly subcutaneous rilonacept 160 mg for prevention of gout flares in patients initiating or continuing urate-lowering therapy (ULT).

Methods.

This phase III study was conducted in the United States, South Africa, Europe, and Asia. Adults (n = 1315, 18–80 yrs) with gout, who were initiating or continuing ULT, were randomized to treatment with weekly subcutaneous injections of rilonacept 160 mg or placebo for 16 weeks followed by a 4-week safety followup. The primary endpoint was safety, assessed by adverse events (AE) and laboratory values. Efficacy was a secondary endpoint.

Results.

Demographic and clinical characteristics were similar between treatments; predominantly male (87.8%), mean age 52.7 ± 11.3 years. Patients with ≥ 1 AE were 66.6% with rilonacept versus 59.1% placebo, with slightly more AE-related withdrawals with rilonacept (4.7% vs 3.0%) because of the greater incidence of injection site reactions (15.2% rilonacept, 3.3% placebo). Serious AE were similar in both groups, as were serious infections (0.9% placebo, 0.5% rilonacept); no tuberculosis or opportunistic infections occurred. Most common AE were headache, arthralgia, injection site erythema, accidental overdose, and pain in extremity. Of the 6 deaths, only 1 in the placebo group was considered treatment-related. At Week 16, rilonacept resulted in 70.3% fewer gout flares per patient (p < 0.0001), fewer patients with ≥ 1 and ≥ 2 gout flares (p < 0.0001), and 64.9% fewer gout flare days (p < 0.0001) relative to placebo.

Conclusion.

Weekly subcutaneous administration of rilonacept 160 mg showed no new safety signals. The safety profile was consistent with previous studies. Rilonacept also significantly reduced the risk of gout flares. Clinicaltrials.gov identifier NCT00856206; EudraCT No. 2008-007784-16.

The impact of gout on patient's lives: a study of African-American and Caucasian men and women with gout

Introduction

The aim of this study was to examine the impact of gout on quality of life (QOL) and study differences by gender and race.

Methods

Ten race- and sex-stratified nominal groups were conducted, oversampling for African-Americans and women with gout. Patients presented, discussed, combined and rank-ordered their concerns.

Results

A total of 62 patients with mean age 65.1 years, 60% men, 64% African-American, participated in 10 nominal groups: African-American men (n = 23; 3 groups); African-American women (n = 18; 3 groups); Caucasian men (n = 15; 3 groups); and Caucasian women (n = 6; 1 group). The most frequently cited high-ranked concerns among the ten nominal groups were: (1) effect of gout flare on daily activities (n = 10 groups); (2) work disability (n = 8 groups); (3) severe pain (n = 8 groups); (4) joint swelling and tenderness (n = 6 groups); (5) food restrictions (n = 6 groups); (6) medication related issues (n = 6 groups); (7) dependency on family and others (n = 5 groups); (8) emotional Impact (n = 5 groups); (9) interference with sexual function (n = 4 groups); (10) difficulty with shoes (n = 4 groups); and (11) sleep disruption (n = 4 groups). Compared with men, women ranked the following concerns high more often: problems with shoes (n = 4 versus n = 0 groups); dependency (n = 3 versus n = 2 groups); and joint/limb deformity (n = 2 versus n = 0 group). Compared with Caucasians, African-Americans ranked the following concerns high more often: dietary restrictions (n = 6 versus n = 0 groups); severe pain (n = 6 versus n = 2 groups); gout bringing the day to a “halt” (n = 2 versus n = 0 group); effect on emotional health (n = 4 versus n = 1 groups); and the need for canes/crutches during flares (n = 2 versus n = 0 group).

Conclusions

Gout has a significant impact on a patient’s QOL. Important differences in the impact of gout by gender and race were noted.

Reduced creatinine clearance is associated with early development of subcutaneous tophi in people with gout

Background

Although typically a late feature of gout, tophi may present early in the course of disease. The aim of this study was to identify factors associated with the presence of early tophaceous disease.

Methods

People with gout for <10 years were prospectively recruited, and had a comprehensive clinical assessment including examination for subcutaneous tophi. The clinical factors independently associated with the presence and number of tophi were analyzed using regression models.

Results

Of the 290 participants, there were 47 (16.2%) with clinically apparent tophi. In univariate analysis, those with tophi were older, were more frequently taking diuretics and colchicine prophylaxis, and had lower creatinine clearance. The association between the presence of tophi and creatinine clearance was strongest in those with creatinine clearance ≤30 ml/min. In logistic regression analysis, creatinine clearance ≤30 ml/min was associated with the presence of tophi, even after adjusting for ethnicity, corticosteroid use, colchicine use and diuretic use (multivariate adjusted odds ratio 7.0, p = 0.005). Participants with tophi reported higher frequency of gout flares, pain scores, patient global assessment scores, and HAQ scores.

Conclusions

The presence of tophi is associated with more symptomatic disease in people with gout for <10 years. Creatinine clearance is independently associated with early presentation of subcutaneous tophi.

The Gout Assessment Questionnaire 2.0: cross-cultural translation into Dutch, aspects of validity and linking to the International Classification of Functioning, Disability and Health

OBJECTIVES

The Gout Assessment Questionnaire 2.0 (GAQ2.0) is a disease-specific patient-reported outcome measure for gout that distinguishes five different subscales and comprises overall 31 questions. The aims of this study were to translate the GAQ2.0 into Dutch and to test clinimetric properties.

METHODS

Recommendations for translation and cross-cultural adaptation were followed and no cultural adaptations were needed. The resulting Dutch GAQ2.0 was administered to patients registered at the rheumatology outpatient clinic diagnosed with gout. Internal consistency was tested using Cronbach's α, reliability using intraclass correlation coefficient (ICC), content validity by linkage to the International Classification of Functioning, Disability and Health (ICF) and construct validity by correlating the subscales of the GAQ2.0 with the HAQ disability index (HAQ-DI) and 36-item Short Form Health Survey (SF-36).

RESULTS

A total of 126 patients [106 (84%) male, mean age 66.6 years (s.d. 10.4), mean disease duration 11.2 years (s.d. 10.6)] completed a number of questionnaires, including the GAQ2.0, HAQ-DI and SF-36, and underwent a clinical examination. Internal consistency was sufficient (Cronbach's α = 0.83-0.94), except for the subscale gout medication side effects (Cronbach's α = 0.51). Test-retest reliability was good (ICCs 0.73-0.86) for all subscales, but moderate for the subscale unmet gout treatment need (ICC 0.56). Gout impact (GI) subscale scores showed only weak to moderate correlations with HAQ-DI and SF-36, but stronger emphasis on the emotional consequences of gout. Also, it correlated better with gout-specific outcomes such as the number of gout flares and pain.

CONCLUSION

The Dutch GAQ2.0 shows sufficient evidence of validity to assess disease-specific functioning and health in patients with gout and seems to capture different aspects than those represented in the HAQ and SF-36.

Trends in physician diagnosed gout and gout therapies in the US: results from the national ambulatory health care surveys 1993 to 2009

Introduction

Gouty arthritis (gout) is primarily cared for in ambulatory care settings. Although the prevalence of gout in the US is thought to be increasing, there have been few data on this as well as temporal changes in gout medication use.

Methods

We analyzed annual visit and drug utilization data from national sample surveys of physician practices and hospital outpatient clinics in the US from 1993 to 2009. Gout diagnosis was recorded by individual physicians.

Result

The frequency of visits for gout increased three-fold from 1993 through 2009; most of the increases were observed from 2003 onwards. The increase was only partly explained by changes in age and gender composition of the surveys over time. A concomitant increase in prescriptions for allopurinol and colchicine and decrease in prescriptions for anti-inflammatories was observed. Aspirin use, a putative risk factor for gout and gout flares, increased substantially over this period. Probenecid use was negligible. Frequency of systemic steroid use has not changed over time.

Conclusions

The number of ambulatory visits for gout has increased almost three-fold in the first decade of the millennium coinciding with increases in physician and patient awareness. This increase was primarily due to visits among the elderly. Uricosuric use remained negligible whereas the uses of allopurinol and colchicine have increased rapidly. Use of traditional non-steroidals has declined, possibly due to safety concerns whereas glucocorticoid use remains unchanged.

Tophus burden reduction with pegloticase: results from phase 3 randomized trials and open-label extension in patients with chronic gout refractory to conventional therapy

INTRODUCTION

Two replicate randomized, placebo-controlled six-month trials (RCTs) and an open-label treatment extension (OLE) comprised the pegloticase development program in patients with gout refractory to conventional therapy. In the RCTs, approximately 40% of patients treated with the approved dose saw complete response (CR) of at least one tophus. Here we describe the temporal course of tophus resolution, total tophus burden in patients with multiple tophi, tophus size at baseline, and the relationship between tophus response and urate-lowering efficacy.

METHODS

Baseline subcutaneous tophi were analyzed quantitatively using computer-assisted digital images in patients receiving pegloticase (8 mg biweekly or monthly) or placebo in the RCTs, and pegloticase in the OLE. Tophus response, a secondary endpoint in the trials, was evaluated two ways. Overall tophus CR was the proportion of patients achieving a best response of CR (without any new/enlarging tophi) and target tophus complete response (TT-CR) was the proportion of all tophi with CR.

RESULTS

Among 212 patients randomized in the RCTs, 155 (73%) had ≥ 1 tophus and 547 visible tophi were recorded at baseline. Overall tophus CR was recorded in 45% of patients in the biweekly group (P = 0.002 versus placebo), 26% in the monthly group, and 8% in the placebo group after six months of RCT therapy. TT-CR rates at six months were 28%, 19%, and 2% of tophi, respectively. Patients meeting the primary endpoint of sustained urate-lowering response to therapy (responders) were more likely than nonresponders to have an overall tophus CR at six months (54% vs 20%, respectively and 8% with placebo).

CONCLUSIONS

Pegloticase reduced tophus burden in patients with refractory tophaceous gout, especially those achieving sustained urate-lowering. Complete resolution of tophi occurred in some patients by 13 weeks and in others with longer-term therapy.

TRIAL REGISTRATIONS

NCT00325195, NCT01356498.

As compared to allopurinol, urate-lowering therapy with febuxostat has superior effects on oxidative stress and pulse wave velocity in patients with severe chronic tophaceous gout

We prospectively evaluated whether an effective 12-month uric acid-lowering therapy (ULT) with the available xanthine oxidase (XO) inhibitors allopurinol and febuxostat in patients with chronic tophaceous gout has an impact on oxidative stress and/or vascular function. Patients with chronic tophaceous gout who did not receive active ULT were included. After clinical evaluation, serum uric acid levels (SUA) and markers of oxidative stress were measured, and carotid-femoral pulse wave velocity (cfPWV) was assessed. Patients were then treated with allopurinol (n = 9) or with febuxostat (n = 8) to target a SUA level ≤ 360 μmol/L. After 1 year treatment, the SUA levels, markers of oxidative stress and the cfPWV were measured again. Baseline characteristics of both groups showed no significant differences except a higher prevalence of moderate impairment of renal function (estimated glomerular filtration rate <60 ml/min) in the febuxostat group. Uric acid lowering with either inhibitors of XO resulted in almost equally effective reduction in SUA levels. The both treatment groups did not differ in their baseline cfPWV (allopurinol group: 14.1 ± 3.4 m/s, febuxostat group: 13.7 ± 2.7 m/s, p = 0.80). However, after 1 year of therapy, we observed a significant cfPWV increase in the allopurinol group (16.8 ± 4.3 m/s, p = 0.001 as compared to baseline), but not in the febuxostat patients (13.3 ± 2.3 m/s, p = 0.55). Both febuxostat and allopurinol effectively lower SUA levels in patients with severe gout. However, we observed that febuxostat also appeared to be beneficial in preventing further arterial stiffening. Since cardiovascular events are an important issue in treating patients with gout, this unexpected finding may have important implications and should be further investigated in randomized controlled trials.

Health-related quality of life in gout: a systematic review

Objectives. To identify the instruments that have been used to measure health-related quality of life (HRQOL) in gout and assess their clinimetric properties, determine the distribution of HRQOL in gout and identify factors associated with poor HRQOL.

Methods. Medline, CINAHL, EMBASE and PsycINFO were searched from inception to October 2012. Search terms pertained to gout, health or functional status, clinimetric properties and HRQOL. Study data extraction and quality assessment were performed by two independent reviewers.

Results. From 474 identified studies, 22 met the inclusion criteria. Health Assessment Questionnaire Disability Index (HAQ-DI) and Short Form 36 (SF-36) were most frequently used and highest rated due to robust construct and concurrent validity, despite high floor and ceiling effects. The Gout Impact Scale had good content validity. Gout had a greater impact on physical HRQOL compared to other domains. Both gout-specific features (attack frequency and intensity, intercritical pain and number of joints involved) and comorbid disease were associated with poor HRQOL. Evidence for objective features such as tophi and serum uric acid was less robust. Limitations of existing studies include cross-sectional design, recruitment from specialist clinic settings and frequent use of generic instruments.

Conclusion. Most studies have used the generic HAQ-DI and SF-36. Gout-specific characteristics and comorbidities contribute to poor HRQOL. There is a need for a cohort study in primary care (where most patients with gout are treated) to determine which factors predict changes in HRQOL over time. This will enable those at risk of deterioration to be identified and better targeted for treatment.