Evaluation of urate-lowering therapy in hyperuricemia patients: a systematic review and Bayesian network meta-analysis of randomized controlled trials

Estimated excretion and clearance of uric acid as optimal surrogate indices for daily urinary uric acid excretion

OBJECTIVES

Daily uric acid excretion (Eua) is an essential index for patients with gout/hyperuricaemia. We identified alternative indices most correlated with 24-hour uric acid clearance (Cua 24 h) and 24-hour Eua (Eua 24 h) using data from the reference interval of urinary clearance and excretion of urate study.

METHODS

The subjects were indoor workers aged 20-65 years who met the Clinical and Laboratory Standards Institute Guidelines C28-A3c. Alternative indices using spot urine were urine uric acid creatinine ratio, Cua-creatinine clearance ratio (Cua/Ccr), Eua-CCr ratio (Eua/Ccr), estimated Cua (eCua), and estimated Eua (eEua). eCua and eEua are the values obtained by multiplying Cua/Ccr and Eua/Ccr with the estimated glomerular filtration rate.

RESULTS

The final number of subjects analysed was 739. Among the indices using spot urine, eCua and eEua showed the highest correlation with Cua 24 h and Eua 24 h, respectively. Compared with Cua 60 min and Eua 60 min obtained from 60-min urine collection, eCua and eEua showed lower root means squared error, lower bias, and significantly higher accuracy of within 30% and within 15%.

CONCLUSIONS

The newly proposed eCua and eEua may be appropriate from a practical perspective.

Cardiovascular and kidney outcomes of uric acid-lowering therapy in patients with different kidney functions: study protocol for a systematic review, pairwise and network meta-analysis

INTRODUCTION

Hyperuricaemia has been implicated in the development of kidney function in populations with chronic kidney disease; however, the benefits of urate-lowering therapy (ULT) remain uncertain in different clinical studies. The different kidney functions of enrolled populations and distinct pharmacokinetic characteristics of ULT might be of the essence for the contrasting results. In this study, we will synthesise all available data from randomised controlled trials (RCTs) and cohort studies, then evaluate the outcomes of ULT in patients stratified by different estimated glomerular filtration rate (eGFR) stratifications. Furthermore, we will attempt to explore a relatively optimal ULT regimen using a Bayesian network meta-analysis in different eGFRs.

METHODS AND ANALYSIS

We searched published and unpublished data from MEDLINE, EMBASE, the Cochrane Central Register of Controlled trials and ClinicalTrials.gov website (before March 2022) for RCTs and cohort studies without language restriction. In the pairwise meta-analysis, all regimens of ULT will be pooled as a whole and compared with controls in different eGFRs. The random-effects model will be applied to generate the summary values using the software Stata V.12.0 (StataCorp). Network meta-analysis within a Bayesian framework will be conducted to explore the relative efficacy profiles of different ULTs and to find optimal ULT in different eGFRs. The software of WinBUGS V.1.4.3 and R2WinBUGS package of R V.3.1.1 will be used in the network meta-analysis. Primary outcomes will be the occurrence of major cardiovascular events and kidney failure events. Secondary outcomes will include the rate of change in eGFR per year, all-cause death, changes in serum uric acid level and major adverse events. Two authors will independently review study selection, data extraction and quality assessment.

ETHICS AND DISSEMINATION

The meta-analysis does not require ethical certification. The results will be disseminated through publication in a peer-reviewed journal and through presentations at academic conferences.

PROSPERO REGISTRATION NUMBER

CRD42021226163.

Medications for gout and its comorbidities: mutual benefits?

PURPOSE OF REVIEW

To review recent literature with relevance to the management of multimorbid patients with gout, i.e., gout medication repurposed for comorbidities and vice versa.

RECENT FINDINGS

Adding to the previous success of interleukin-1 inhibition, two trials on low-dose colchicine's role in cardiovascular disease (CVD) demonstrated potential benefits in patients with or without gout. In Colchicine Cardiovascular Outcomes Trial, a composite CVD endpoint was reduced by 23% among patients who had experienced a recent myocardial infarction. In Low-Dose Colchicine 2, the composite CVD endpoint was reduced 31% among those with stable coronary artery disease. Use of urate-lowering therapy (ULT) for renal protection in patients without gout produced null results. Allopurinol did not benefit the glomerular filtration rate in two trials (Controlled trial of slowing of Kidney Disease progression From the Inhibition of Xanthine oxidase and Preventing Early Renal Function Loss) among patients with chronic kidney disease (with or without hyperuricemia, but not gout). SGLT-2 inhibitors, a medication recommended for patients with diabetes and CVD, diabetic kidney disease, or heart failure, demonstrated a protective effect against gout flares in a secondary trial analysis and a large observational study.

SUMMARY

The role of colchicine may expand beyond gout flare prevention to patients with existing CVD. The renal benefit of ULT among patients with gout remains unclear. SGLT-2 inhibitors may benefit diabetic patients who have gout as a comorbidity.