Efficacy and Safety of Pharmacologic Interventions in Patients Experiencing a Gout Flare: A Systematic Review and Network Meta-Analysis

How do network meta-analyses address intransitivity when assessing certainty of evidence: a systematic survey

OBJECTIVES

To describe how systematic reviews with network meta-analyses (NMAs) that used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) NMA approach addressed intransitivity when assessing certainty of evidence.

DESIGN

Systematic survey.

DATA SOURCES

Medline, Embase and Cochrane Database of Systematic Reviews from September 2014 to October 2022.

ELIGIBILITY CRITERIA

Systematic reviews of randomised controlled trials with aggregate data NMAs that used the GRADE NMA approach for assessing certainty of evidence.

DATA EXTRACTION AND SYNTHESIS

We documented how reviewers described methods for addressing intransitivity when assessing certainty of evidence, how often they rated down for intransitivity and their explanations for rating down.

RESULTS

Of the 268 eligible systematic reviews, 44.8% (120/268) mentioned intransitivity when describing methods for assessing the certainty of evidence. Of these, 28.3% (34/120) considered effect modifiers and from this subset, 67.6% (23/34) specified the effect modifiers; however, no systematic review noted how they chose the effect modifiers. 15.0% (18/120) mentioned looking for differences between the direct comparisons that inform the indirect estimate. No review specified a threshold for difference in effect modifiers between the direct comparisons that would lead to rating down for intransitivity. Reviewers noted rating down indirect evidence for intransitivity in 33.1% of systematic reviews, and noted intransitivity for network estimates in 23.0% of reviews. Authors provided an explanation for rating down for intransitivity in 59.6% (31/52) of the cases in which they rated down. Of the 31 in which they provided an explanation, 74.2% (23/31) noted they detected differences in effect modifiers and 67.7% (21/31) specified in what effect modifiers they detected differences.

CONCLUSIONS

A third of systematic reviews with NMAs using the GRADE approach rated down for intransitivity. Limitations in reporting of methods to address intransitivity proved considerable. Whether the problem is that reviewers neglected to address rating down for transitivity at all, or whether they did consider but not report, is not clear. At minimum systematic reviews with NMAs need to improve their reporting practices regarding intransitivity; it may well be that they need to improve their practice in transitivity assessment. How to best address intransitivity may remain unclear for many reviewers thus additional GRADE guidance providing practical instructions for addressing intransitivity may be desirable.

Update on gout management: what is old and what is new

PURPOSE OF REVIEW

The global burden of gout is rising, as are the prevalence of associated comorbidities, all-cause mortality and societal costs. In this review, we discuss recent advances in epidemiology and treatment strategies for gout.

RECENT FINDINGS

Genetic factors and obesity are prominent contributors to hyperuricemia and gout, while dietary factors contribute to less variance in serum urate, though can still have some contribution to population attributable risk. A consensus statement by the Gout, Hyperuricemia and Crystal-Associated Disease Network outlined appropriate terminology regarding gout, which will aid in communication about various aspects of the disease. The 2020 American College of Rheumatology gout guideline offers comprehensive evidence-based recommendations for the management of hyperuricemia using urate-lowering therapy, prophylaxis when initiating urate-lowering therapy, treatment of gout flare and adjunctive management strategies. There is improved understanding of risk factors for allopurinol hypersensitivity syndrome and well tolerated use of allopurinol in chronic kidney disease. Trial data have provided new insights regarding cardiovascular risk with febuxostat. Several new drug therapies are being tested for both urate-lowering efficacy and gout flare management.

SUMMARY

Although there have been significant advances in understanding of risk factors and treatment approaches, gout remains suboptimally managed. There is substantial need for improving gout management efforts and gout education among patients and clinicians.

Gouty Arthropathy: Review of Clinical Manifestations and Treatment, with Emphasis on Imaging

Gout, a crystalline arthropathy caused by the deposition of monosodium urate crystals in the articular and periarticular soft tissues, is a frequent cause of painful arthropathy. Imaging has an important role in the initial evaluation as well as the treatment and follow up of gouty arthropathy. The imaging findings of gouty arthropathy on radiography, ultrasonography, computed tomography, dual energy computed tomography, and magnetic resonance imaging are described to include findings of the early, acute and chronic phases of gout. These findings include early monosodium urate deposits, osseous erosions, and tophi, which may involve periarticular tissues, tendons, and bursae. Treatment of gout includes non-steroidal anti-inflammatories, colchicine, glucocorticoids, interleukin-1 inhibitors, xanthine oxidase inhibitors, uricosuric drugs, and recombinant uricase. Imaging is critical in monitoring response to therapy; clinical management can be modulated based on imaging findings. This review article describes the current standard of care in imaging and treatment of gouty arthropathy.

What's new on the front-line of gout pharmacotherapy?

INTRODUCTION

Gout is the most common form of inflammatory arthritis affecting millions of people around the world. Painful flares and tophaceous deposits can be debilitating, reducing quality of life among those affected and putting strain on health care systems.

AREAS COVERED

This review provides an overview of the treatment of gout for flare pain management and lowering serum urate. Firstline agents are discussed with emphasis on emerging evidence. Novel therapies are also covered.

EXPERT OPINION

Lifestyle modifications form a part of gout prevention. Regarding gout flare pharmacotherapy NSAIDs, colchicine and glucocorticoids are first line agents. The IL-1β antagonists also are highly effective for arresting flares but their cost-effectiveness render them as salvage therapies. Allopurinol is an agent of first choice for urate lowering therapy (ULT). In South East Asian and Black populations screening for HLA*B58:01 mutation is a cost-effective approach to decrease the occurrence of the rare but potentially very serious allopurinol hypersensitivity syndrome (AHS.). Febuxostat is another efficacious urate lowering therapy but it has received U.S. FDA black box warning for cardiovascular safety and careful consideration is warranted before its initiation in patients with high cardiovascular risk. Novel uricosurics are a class for continued drug development; verinurad and arhalofenate are agents with future promise. For patients with recalcitrant gout, pegloticase is another effective option in the rheumatologist's armamentarium. Its immunogenicity significantly threatens the achievement of sustained urate lowering responses. Abrogating pegloticase's immunogenicity with immunomodulatory co-therapy may lend to sustained efficacy.

Non-steroidal anti-inflammatory drugs for acute gout

BACKGROUND

Gout is an inflammatory arthritis resulting from the deposition of monosodium urate crystals in and around joints. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat acute gout. This is an update of a Cochrane Review first published in 2014.

OBJECTIVES

To assess the benefits and harms of non-steroidal anti-inflammatory drugs (NSAIDs) (including cyclo-oxygenase-2 (COX-2) inhibitors (COXIBs)) for acute gout.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase for studies to 28 August 2020. We applied no date or language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) and quasi-RCTs comparing NSAIDs with placebo or another therapy for acute gout. Major outcomes were pain, inflammation, function, participant-reported global assessment, quality of life, withdrawals due to adverse events, and total adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included in this update 28 trials (3406 participants), including 5 new trials. One trial (30 participants) compared NSAIDs to placebo, 6 (1244 participants) compared non-selective NSAIDs to selective cyclo-oxygenase-2 (COX-2) inhibitors (COXIBs), 5 (712 participants) compared NSAIDs to glucocorticoids, 13 compared one NSAID to another NSAID (633 participants), and single trials compared NSAIDs to rilonacept (225 participants), acupuncture (163 participants), and colchicine (399 participants). Most trials were at risk of selection, performance, and detection biases. We report numerical data for the primary comparison NSAIDs versus placebo and brief results for the two comparisons - NSAIDs versus COX-2 inhibitors and NSAIDs versus glucocorticoids. Low-certainty evidence (downgraded for bias and imprecision) from 1 trial (30 participants) shows NSAIDs compared to placebo. More participants (11/15) may have a 50% reduction in pain at 24 hours with NSAIDs than with placebo (4/15) (risk ratio (RR) 2.7, 95% confidence interval (CI) 1.1 to 6.7), with absolute improvement of 47% (3.5% more to 152.5% more). NSAIDs may have little to no effect on inflammation (swelling) after four days (13/15 participants taking NSAIDs versus 12/15 participants taking placebo; RR 1.1, 95% CI 0.8 to 1.5), with absolute improvement of 6.4% (16.8% fewer to 39.2% more). There may be little to no difference in function (4-point scale; 1 = complete resolution) at 24 hours (4/15 participants taking NSAIDs versus 1/15 participants taking placebo; RR 4.0, 95% CI 0.5 to 31.7), with absolute improvement of 20% (3.3% fewer to 204.9% more). NSAIDs may result in little to no difference in withdrawals due to adverse events (0 events in both groups) or in total adverse events; two adverse events (nausea and polyuria) were reported in the placebo group (RR 0.2, 95% CI 0.0, 3.8), with absolute difference of 10.7% more (13.2% fewer to 38% more). Treatment success and health-related quality of life were not measured. Moderate-certainty evidence (downgraded for bias) from 6 trials (1244 participants) shows non-selective NSAIDs compared to selective COX-2 inhibitors (COXIBs). Non-selective NSAIDs probably result in little to no difference in pain (mean difference (MD) 0.03, 95% CI 0.07 lower to 0.14 higher), swelling (MD 0.08, 95% CI 0.07 lower to 0.22 higher), treatment success (MD 0.08, 95% CI 0.04 lower to 0.2 higher), or quality of life (MD -0.2, 95% CI -6.7 to 6.3) compared to COXIBs. Low-certainty evidence (downgraded for bias and imprecision) suggests no difference in function (MD 0.04, 95% CI -0.17 to 0.25) between groups. Non-selective NSAIDs probably increase withdrawals due to adverse events (RR 2.3, 95% CI 1.3 to 4.1) and total adverse events (mainly gastrointestinal) (RR 1.9, 95% CI 1.4 to 2.8). Moderate-certainty evidence (downgraded for bias) based on 5 trials (712 participants) shows NSAIDs compared to glucocorticoids. NSAIDs probably result in little to no difference in pain (MD 0.1, 95% CI -2.7 to 3.0), inflammation (MD 0.3, 95% CI 0.07 to 0.6), function (MD -0.2, 95% CI -2.2 to 1.8), or treatment success (RR 0.9, 95% CI 0.7 to 1.2). There was no difference in withdrawals due to adverse events with NSAIDs compared to glucocorticoids (RR 2.8, 95% CI 0.5 to 14.2). There was a decrease in total adverse events with glucocorticoids compared to NSAIDs (RR 1.6, 95% CI 1.0 to 2.5).

AUTHORS' CONCLUSIONS

Low-certainty evidence from 1 placebo-controlled trial suggests that NSAIDs may improve pain at 24 hours and may have little to no effect on function, inflammation, or adverse events for treatment of acute gout. Moderate-certainty evidence shows that COXIBs and non-selective NSAIDs are probably equally beneficial with regards to improvement in pain, function, inflammation, and treatment success, although non-selective NSAIDs probably increase withdrawals due to adverse events and total adverse events. Moderate-certainty evidence shows that systemic glucocorticoids and NSAIDs probably are equally beneficial in terms of pain relief, improvement in function, and treatment success. Withdrawals due to adverse events were also similar between groups, but NSAIDs probably result in more total adverse events. Low-certainty evidence suggests no difference in inflammation between groups. Only low-certainty evidence was available for the comparisons NSAID versus rilonacept and NSAID versus acupuncture from single trials, or one NSAID versus another NSAID, which also included many NSAIDs that are no longer in clinical use. Although these data were insufficient to support firm conclusions, they do not conflict with clinical guideline recommendations based upon evidence from observational studies, findings for other inflammatory arthritis, and expert consensus, all of which support the use of NSAIDs for acute gout.

Treatment advances in gout

The purpose of gout treatment is to alleviate symptoms of flares, prevent flares from recurring by lowering serum urate, and minimize structural joint damage and functional impairment. In recent years, several new medications to treat gout have been developed, and novel agents continue to be investigated, in addition to several long-established treatments. Although a number of effective therapies are available, optimal management and outcomes are frequently not achieved due to physician under prescribing of urate-lowering therapy (ULT) and poor adherence with therapy when it is prescribed. This article reviews recent developments in the management of gout with reference to recently published clinical guidelines, outlines some important questions regarding the safety and efficacy of particular agents, and remaining gaps in our knowledge about the most effective strategies for using currently available treatments.

Efficacy and safety of pharmacologic interventions in patients experiencing a gout flare: A systematic review and network meta-analysis: Comment on the article by Zeng et al

I appreciated the network meta-analysis of pharmacologic interventions in acute gout by Zeng et al. recently published in Arthritis Care and Research (1). However, I was surprised that the authors choose to break down the analysis of nonsteroidal anti-inflammatory drugs (NSAIDs) by chemical class.