Uric Acid-lowering Therapy Research Articles

Uric acid and progression of chronic kidney disease.

The association between serum uric acid levels and human disease has garnered intense interest over the last decade including chronic kidney disease. Animal studies have provided evidence for a potential mechanistic role of uric acid in promoting progression of chronic kidney disease. Epidemiologic studies have also suggested an association between elevated serum uric acid levels and worsening renal function in the general population as well as in patients with chronic kidney disease. However, there is currently insufficient evidence to recommend the use of uric acid-lowering therapy to delay progression of chronic kidney disease in this patient population. Adequately powered, randomized, placebo-controlled trials are required to more precisely evaluate the risk and benefits of uric acid-lowering therapy in pediatric patients.

Effects of uric acid-lowering therapy on the progression of chronic kidney disease: a systematic review and meta-analysis

Objectives: Whether uric acid levels were associated with the progression of chronic kidney disease (CKD) remained controversial. This meta-analysis was aimed to assess the effect of lowering serum uric acid therapy on the progression of CKD to clarify the role of uric acid in the progression of CKD indirectly.Methods: Pubmed, Embase, the Cochrane library, CBM were searched for randomized controlled trials (RCTs) that assessed the efficiency of lowering serum uric acid therapy on the progression of CKD without language restriction. Summary estimates of weighted mean differences (WMDs) and relative risk (RR) were obtained by using random-effect or fixed-effect models. Sensitivity analyses were performed to identify the source of heterogeneity.Results: A total of 12 randomized controlled trials with 832 CKD participants were included in the analysis. Pooled estimate for eGFR was in favor of lowering serum uric acid therapy with a mean difference (MD) of 3.88 ml/min/1.73 m2, 95% CI 1.26–6.49 ml/min/1.73 m2, p = .004 and this was consistent with results for serum creatinine. The risk of worsening of kidney function or ESRD or death was significantly decreased in the treatment group compared to the control group (RR 0.39, 95% CI 0.28–0.52, p< .01).Conclusions: Uric acid-lowering therapy may be effective in retarding the progression of CKD. Further randomized controlled trials should be performed to confirm the effect of lowering serum uric acid therapy on the progression of CKD.

Can the use of uric acid-lowering therapies in adults delay the progression of chronic kidney disease?

Can the use of uric acid-lowering therapies in adults delay the progression of chronic kidney disease?

Effects of uric acid-lowering therapy in patients with chronic kidney disease: A meta-analysis

Background and objectivesThe effects of uric acid-lowering therapy in patients with chronic kidney disease (CKD) remain uncertain. Therefore, we undertook a systematic review and meta-analysis to investigate the effects of uric acid-lowering agents on major clinical outcomes of CKD.Design, setting, participants, and measurementsAccording to the pre-specified protocol that was registered with PROSPERO (No. CRD42016038030), we searched systematically in MEDLINE, EMBASE, and the Cochrane Library for trials up to February 2016. Prospective, randomized, controlled trials assessing the effects of uric acid-lowering agents on cardiovascular and kidney outcomes in patients with CKD were included. Random-effects analytical methods were used.ResultsSixteen eligible trials were identified, providing data for 1,211 patients with CKD, including 146 kidney failure events and 69 cardiovascular events. Uric acid-lowering therapy produced a 55% relative risk (RR) reduction (95% confidence interval [95% CI], 31–64) for kidney failure events (P < 0.001), and a 60% RR reduction (95% CI, 17–62) for cardiovascular events (P < 0.001), but had no significant effect on the risk of all-cause death (RR, 0.86; 95% CI, 0.50–1.46). The mean differences in rate of decline in the estimated glomerular filtration rate (4.10 mL/min/1.73 m2 per year slower in uric acid-lowering therapy recipients, 95% CI, 1.86–6.35) and the standardized mean differences in the change in proteinuria or albuminuria (−0.23 units of standard deviation greater in uric acid-lowering therapy recipients; 95% CI, −0.43 to −0.04) were also statistically significant.ConclusionsUric acid-lowering therapy seemed to improve kidney outcomes and reduce the risk of cardiovascular events in adults with CKD.

Uric acid lowering therapies for preventing or delaying the progression of chronic kidney disease.

Non-randomised data have shown a link between hyperuricaemia and the progression or development of chronic kidney disease (CKD). If this is correct, urate lowering therapy might form an important part of chronic kidney disease care, reducing risks for cardiovascular outcomes and end-stage kidney disease. This review aims to study the benefits and harms of uric acid lowering therapy on the progression of CKD and other cardiovascular endpoints. We searched the Cochrane Kidney and Transplant Specialised Register to 20 July 2017 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. All randomised controlled trials testing primary urate lowering therapy in patients with or without CKD. Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI) for dichotomous outcomes or mean difference (MD) for continuous outcomes, or standardised mean difference (SMD) if different scales were used. Twelve studies (1187 participants) were included in the review. Risk of bias was unclear for the majority of domains in each study.Uric acid lowering therapy may make little or no difference in death at six months (2 studies, 498 participants: RR 1.66, 95% CI 0.61 to 4.48) or two years (2 studies, 220 participants): RR 0.13, 95% CI 0.02 to 1.06) (low certainty evidence). Uric acid lowering therapy may make little of no difference (low certainty evidence) in the incidence of ESKD at one or two years. Kidney function may be improved by uric acid lowering therapy at one year with a reduction in serum creatinine (2 studies, 83 participants: MD -73.35 µmol/L, 95% CI -107.28 to -39.41) and a rise in eGFR (1 study, 113 participants: MD 5.50 mL/min/1.73 m2, 95% CI 0.59 to 10.41). However it probably makes little or no difference to eGFR at two years (2 studies, 164 participants: MD 4.00 mL/min, 95% CI -3.28 to 11.28). Uric acid lowering therapy reduced uric acid levels at all time points (3, 4, 6, 12 and 24 months) (high certainty evidence).There is insufficient evidence to support an effect on blood pressure, proteinuria or other cardiovascular markers by uric acid lowering therapy. It should be noted that the apparent benefits of treatment were not apparent at all time points, introducing the potential for bias. There is limited data which suggests uric acid lowering therapy may prevent progression of chronic kidney disease but the conclusion is very uncertain. Benefits were not observed at all time points and study quality was generally low. Larger studies are required to study the effect of uric acid lowering therapy on CKD progression. Three ongoing studies will hopefully provide much needed high quality data.

A comparative study of efficacy of febuxostat and allopurinol regimens in patients of hyperuricemia

Background: Gout, resulting from the precipitation of urate crystals in the tissues and the subsequent inflammatory response, causes an exquisitely painful distal monoarthritis alongwith joint destruction, subcutaneous deposits (tophi), renal calculi. The main culprit is uric Acid, which is a waste product formed due to purine metabolism. Gout Patients either produce excess Uric acid or are unable to excrete Uric acid produced in normal conditions. Uric acid lowering therapy (ULT) has become popular regarding management of gout. Nowadays. 2 drugs which are responsible for decreasing synthesis of Uric acid are Febuxostat and Allopurinol. The purpose of this study is to determine efficacy of Febuxostat and Allopurinol experienced by patients during course of therapy.Methods: It was an open, prospective, observational, non-invasive, parallel and randomised study, conducted at the Outpatient Department of Urology, Rajindra Hospital, Patiala. It had 60 patients of gout, out which, 30 patients were administered Febuxostat and 30 patients were administered Allopurinol. For each patient, history regarding drug intake was taken, along with analysis of Serum Uric acid profile before prescription and during follow up.Results: The mean age selected for study was 47 years for Febuxostat group and 43 years for Allopurinol group. Mean Urate (mg%) in pre-treatment stage of patients of Febuxostat group is about 8.28 whereas for Allopurinol group its about 8.61. Mean urate levels after 4 follow ups (10 days each) were conducted. The mean Urate level at 10, 20, 30, 40 days were conducted at each group which were found to be statistically significant and the results of Febuxostat group was found to be favourable.Conclusions: Febuxostat, (40mg) given at daily dose was found to have higher efficacy than allopurinol, at a dose of 100mg (zyloric) which is the most commonly prescribed dose in order to lower the serum urate level.

Impact of Uric Acid Levels on Kidney Disease Progression

Background: Hyperuricemia is associated with the progression of chronic kidney disease (CKD), but it is not known whether the relationship is causal. We examined the association of hyperuricemia and uric acid lowering therapy (UALT) with progression of CKD in patients with CKD 3 and 4 in the Cleveland Clinic CKD registry. Methods: We included 1,676 patients with CKD stages 3 and 4 from Ohio, who had measured their uric acid (UA) levels a year prior to the recording of the second eGFR <60 mL/min/1.73 m2, and follow-up eGFR, between 2005 and 2009. Our primary composite outcome included a 50% drop in eGFR or progression to ESRD. Secondary outcomes included the rate of decline in eGFR, all-cause mortality, progression to ESRD, and a composite measure of progression to ESRD or death. We assessed the association between UA, UALT, and outcomes using Cox models and competing risks regression models. Results: In multivariable models, higher UA was associated with the composite endpoint, but it reached statistical significance only in the 4th quartile (≥8.9 mg/dL). Receipt of UALT was significantly associated with increased risk of the composite outcome. Neither UA nor UALT (considered a time-dependent covariate) was significantly associated with mortality. The inference was similar for UA as high vs. low, quartiles, or continuous. Similarly, neither high UA nor UALT were significantly associated with ESRD, the composite of ESRD and mortality, or eGFR decline. Conclusions: Hyperuricemia is associated with increased risk of progression to ESRD in patients with CKD stages 3 and 4, but UALT does not ameliorate the risk, suggesting that the relationship is not causal.

Hyperuricemia is associated with nonalcoholic fatty liver disease activity score in patients with nonalcoholic fatty liver disease: a systematic review and meta-analysis.

Hyperuricemia is a significant risk factor for nonalcoholic fatty liver disease (NAFLD). It may also have an impact on the histologic severity of NAFLD. However, data on this association are limited. We conducted this meta-analysis to investigate the relationship of serum uric acid with liver histologic severity as determined by NAFLD activity score (NAS) in patients with NAFLD. MEDLINE and EMBASE databases were searched through August 2016 for studies that investigated the association between hyperuricemia and NAS among patients with biopsy-proven NAFLD. Pooled odds ratio and 95% confidence interval were calculated using a random-effects model (generic inverse variance method). The between-study heterogeneity of effect size was quantified using the Q statistic and I. Five observational studies with 777 NAFLD patients were identified. Patients with NAFLD who had hyperuricemia had a high NAS (defined as score of ≥5) significantly more often than did those without hyperuricemia with a pooled odds ratio of 2.17 (95% confidence interval: 1.51-3.12). The statistical heterogeneity was low, with I of 16% (Pheterogeneity=0.31). In patients with NAFLD, hyperuricemia is associated with a higher degree of histological liver damage. Further studies are required to establish the role of uric acid-lowering therapy among these patients.

Fabrication of nitrogen-doped carbon dots for screening the purine metabolic disorder in human fluids

Fabrication of nitrogen-doped carbon dots (N-CDs) electrode for the screening of purine metabolic disorder was described in this paper. Peroxynitrite is a short-lived oxidant species that is a potent inducer of cell death. Uric acid (UA) can scavenge the peroxynitrite to avoid the formation of nitrotyrosine, which is formed from the reaction between peroxynitrite and tyrosine (Try). Scavenging the peroxynitrite avoids the inactivation of cellular enzymes and modification of the cytoskeleton. Reduced level of UA decreases the ability of the body from preventing the peroxynitrite toxicity. On the other hand, the abnormal level of UA leads to gout and hyperuricemia. Allopurinol (AP) is administered in UA lowering therapy. Thus, the simultaneous determination of UA, Try and AP using N-CDs modified glassy carbon (GC) electrode was demonstrated for the first time. Initially, N-CDs were prepared from L-asparagine by pyrolysis and characterized by different spectroscopic and microscopic techniques. The HR-TEM image shows that the average size of the prepared N-CDs was 1.8±0.03nm. Further, the N-CDs were directly attached on GC electrode by simple immersion, follows Micheal's nucleophilic addition. XPS of N-CDs shows a peak at 285.3eV corresponds to the formation of C–N bond. The GC/N-CDs electrode shows higher electrocatalytic activity towards UA, Tyr and AP by not only shifting their oxidation potentials toward less positive potential but also enhanced their oxidation currents in contrast to bare GC electrode. The GC/N-CDs electrode shows the limit of detection of 13×10−10M (S/N=3) and the sensitivity of 924μAmM−1cm−2 towards the determination of UA. Finally, the N-CDs modified electrode was utilized for the determination of UA, Tyr and AP in human blood serum and urine samples.

Uric acid lowering therapy for prevention of cardiovascular disease requires further evidence to be validated

It has been observed since the late 19th century that gout is associated with hypertension, diabetes, kidney disease and cardiovascular disease (1). In 1897, Dr. Davis suggested that hypertension in gout might partly be due to hyperuricemia which increases arteriolar tonus (1).

Effects of febuxostat on insulin resistance and expression of high-sensitivity C-reactive protein in patients with primary gout.

We aimed to investigate the effects of febuxostat on IR and the expression of high-sensitivity C-reactive protein (hs-CRP) in patients with primary gout. Forty-two cases of primary gout patients without uric acid-lowering therapy were included in this study. After a physical examination, 20 age- and sex-matched patients were included as normal controls. The levels of fasting insulin (INS), fasting blood glucose (FBG), and hs-CRP were determined. IR was assessed using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). Gout patients had higher levels of UA, INS, HOMA-IR, and hs-CRP than normal controls (P<0.05). After 4-, 12-, and 24-week febuxostat treatments, UA and hs-CRP concentrations were significantly lower than baseline (P<0.05). INS and HOM-IR decreased slightly after a 4-week treatment with febuxostat but declined significantly after 12 and 24weeks of treatment. Importantly, hs-CRP values positively correlated with those of HOMA-IR (r=0.353, P=0.018) and INS (r=0.426, P=0.034). Our findings confirm that IR exists in gout patients and implicate that febuxostat can effectively control the level of serum UA and increase insulin sensitivity in primary gout patients.

Effect of uric acid-lowering therapy on blood pressure: systematic review and meta-analysis

Background: The purpose of this meta-analysis was to determine if uric acid-lowering therapy is associated with a decrease in blood pressure (BP) and serum creatinine levels.Materials and methods: Medline, Cochrane, EMBASE, and Google Scholar databases were searched until 29 June 2016, with keywords: uric-acid-lowering therapy, allopurinol, febuxostat, uricosuric, and BP. Only randomized controlled trials were included. The primary outcomes were reduction in systolic BP (SBP) and diastolic BP (DBP), and secondary was reduction in serum creatinine level.Results: Patients treated with allopurinol had greater reduction in SBP (standardized difference in means [SDM] = 0.321, 95% confidence interval [CI]: 0.145–0.497, p < 0.001), DBP (SDM = 0.260, 95% CI: 0.102 to 0.417, p = 0.001), and creatinine level (SDM = 0.312, 95% CI: 0.008 to 0.615, p = 0.044) than control patients. Subgroup analysis showed that allopurinol significantly decreased SBP whether or not antihypertensive drugs were being administered; a decrease in DBP was only seen in patients receiving antihypertensive drugs. Low-dose allopurinol (≤300 mg/day) was more effective at reducing SBP than high-dose (>300 mg/day) in patients receiving antihypertensive drugs.Conclusions: These results support that allopurinol decreases BP and creatinine levels in patients with hyperuricemia.KEY MESSAGESAllopurinol decreases SBP and DPB, and creatinine levels in patients with hyperuricemia.Allopurinol resulted in a significant decrease in SBP in patients with or without treatment of antihypertensive drugs.A dose of allopurinol of ≤300 mg per day might be more effective than a higher dose.

Hyperuricemia, Hypertension, and Chronic Kidney Disease: an Emerging Association.

Uric acid is a product of purine metabolism and has been linked to gout and kidney calculi. Chronic kidney disease (CKD) and hypertension (HTN) are two major public health problems, and both are associated with increased risk of cardiovascular events. Emerging evidence suggests a pathogenic role of hyperuricemia in the development of HTN and CKD, in addition to progression of CKD, by inducing renal inflammation, endothelial dysfunction, and activation of the renin-angiotensin system. In addition, several epidemiological studies have linked hyperuricemia with an increased risk of HTN and CKD. A few clinical trials have assessed the use of uric acid-lowering therapies such as allopurinol and febuxostat in the management of HTN and delaying progression of CKD. To date, most of these trials are short-term with a small sample size; however, their results are encouraging and provide a rationale for larger randomized controlled trials to establish the role of uric acid-lowering therapies in the management of HTN, in addition to prevention of CKD progression and cardiovascular events.

Characterization of Mesoamerican Nephropathy in a Kidney Failure Hotspot in Nicaragua.

Mesoamerican nephropathy (MeN) is a kidney disease of unknown cause that mainly affects working-age men in Central America. Despite being a major cause of morbidity and mortality in this region, its clinical characteristics have not been well defined. Cross-sectional family-based study. 266 members of 24 families with high chronic kidney disease (CKD) burdens in a MeN hotspot in Northwestern Nicaragua. We compared clinical and biochemical characteristics of affected individuals first with their unaffected relatives and then with NHANES (National Health and Nutrition Examination Survey) participants with CKD in order to reveal identifying features of MeN. CKD defined as serum creatinine level≥ 1.5mg/dL in men and≥1.4mg/dL in women. Clinical and biochemical parameters, including serum sodium, potassium, bicarbonate, calcium, magnesium, phosphorus, and uric acid. Hyperuricemia, in many cases severe, was common among patients with MeN. Uric acid levels in patients with MeN were higher than those in NHANES participants (mean, 9.6 vs 7.4mg/dL for men in each group) despite more frequent use of uric acid-lowering medications in Nicaraguan individuals (71.7% vs 11.2%). In multivariable linear mixed-effects regression analysis, uric acid levels were 2.0mg/dL (95% CI, 1.0-3.0; P<0.001) higher in patients with MeN compared with their NHANES counterparts after adjusting for age, estimated glomerular filtration rate, and uric acid-lowering therapies. In contrast to prior reports, hyponatremia and hypokalemia were not common. CKD defined by single serum creatinine measurement; population likely not representative of full MeN phenotype spectrum across Central America; major differences between MeN and NHANES groups in important characteristics such as age, ancestry, and recruitment method. Hyperuricemia out of proportion to the degree of decreased kidney function was common among Nicaraguan patients with MeN. Our results suggest that rather than being solely a consequence of CKD, hyperuricemia may play a role in MeN pathogenesis, a hypothesis that deserves further study.

Serum Uric Acid Exhibits Inverse Relationship with Estimated Glomerular Filtration Rate

Background: In this study, we investigated the relationship between serum uric acid (SUA) and renal function in a unique patient cohort wherein SUA levels fluctuate during the course of standard care. Methods: Correlation coefficients between SUA and serum creatinine (SCr) and kinetic estimated GFR (KeGFR) were retrospectively investigated in acute myeloid leukemia (AML) patients, and statistically significant and clinically relevant determinants were studied in multiple regression models. Results: One hundred and twenty-six patients were included in the analysis. Baseline SUA was associated with an increased risk for acute kidney injury (AKI; OR 1.27, 95% CI 1.1-1.5, p = 0.003) and laboratory tumor lysis syndrome (OR 1.26, 95% CI 1.1-1.5, p = 0.005). Prophylactic uric acid-lowering therapy and hydration resulted in lower SUA values from baseline in 88.1% of the patients, the lowest values were observed on post-induction day 1 (20.4% reduction). Significant linear correlations were observed between SUA and SCr (r = 0.35, p < 0.001) values with a significant inverse correlation between SUA and KeGFR on day 1 (r = -0.33, p < 0.001) that persisted through day 4. By subgroup analysis, patients with primary AML (r = -0.49, p < 0.001), baseline SUA >5.5 mg/dl (r = -0.41, p = 0.002) and baseline eGFR >60 ml/min/1.73 m² (r = -0.51, p < 0.001) demonstrated robust relationships between SUA and KeGFR. The relationship was more robust when the groups were combined (primary AML plus baseline SUA >5.5 mg/dl plus baseline eGFR >60 ml/min/1.73 m², r = -0.52, p < 0.001). Conclusion: The demonstration of linear relationship between SUA and SCr and inverse relationship between SUA and KeGFR reinforces the emerging translational physiological evidence regarding the role of uric acid in AKI.

Knowledge, illness perceptions and stated clinical practice behaviour in management of gout: a mixed methods study in general practice.

The objective of the present study is to explore knowledge, illness perceptions and stated practice behaviour in relation to gout in primary care. This is a mixed methods study among 32 general practitioners (GPs). The quantitative assessment included the Gout Knowledge Questionnaire (GKQ; range 0–10; better) and Brief Illness Perceptions Questionnaire (BIPQ; nine items, range 0–10; stronger). Structured individual interviews obtained further qualitative insight into knowledge and perceptions, in the context of daily practice. Among 32 GPs, 18 (56.3 %) were male, mean age 44.4 years (SD 9.6) and mean working experience 17.1 years (SD 9.7). Median score [interquartile ranges (IQR)] on the GKQ was 7.8 [6.7–8.9] and 9.0 [8.0–10.0], when presented as open or multiple-choice questions, respectively. The BIPQ (median; [IQR]) revealed that gout was seen as a chronic disease (8.0; [7.0–9.0]), affecting life and emotions moderately (6.5; [5.0–7.0]), having many severe symptoms (8.0; [7.0–9.0]) and in which treatment could be very helpful (8.0; [7.0–9.0]). Further interviews revealed large variation in specific aspects of knowledge and about gaps concerning indications for uric acid-lowering therapy (UALT), duration of UALT, target serum uric acid (sUA) level or duration of prophylactic treatment. Finally, patients’ adherence was not checked systematically. Specific knowledge gaps and discrepancies between perceptions and stated practice behaviour were identified, which might hamper effective management of this well-treatable disease. Improving evidence on the rationale and effectiveness of treatment targets and adherence interventions, tailoring guidelines to general practice and intensification of implementation of guidelines in primary health care seem to be needed.

Uric acid lowering therapy in cardiovascular diseases.

Recent evidence would indicate that high serum uric acid (SUA) levels can be a significant and independent risk factor for hypertension and cardiovascular diseases, such as ischemic heart disease and heart failure. In the last few years an independent risk relationship between hyperuricemia, cardiovascular disease and mortality has also been reported. Hyperuricemia has been shown as an independent risk factor for acute myocardial infarction and an independent and conjoint association of either gout and SUA with total and cardiovascular mortality has been reported, with mortality impact in gout patients increasing with rising SUA concentrations, even for SUA levels in the normal to high range. These findings prompted a growing research interest on the possible benefits of uric acid lowering drugs in cardiovascular diseases. Indeed, clinical studies have reported on the beneficial effects of uric acid lowering drugs, in particular of xanthine oxidase inhibitors, in hypertension, ischemic heart disease and heart failure. Two main mechanisms have been claimed to explain the dangerous effects of hyperuricemia and, as a consequence, the benefits of uric acid lowering therapy: endothelial dysfunction and systemic inflammation. This brief review aims to summarize current evidence from human studies on the role of acid uric lowering therapy in cardiovascular diseases for practical and clinical purposes. The possible mechanisms underlying the benefits of acid uric lowering therapy are also addressed.

An open-label, 6-month study of allopurinol safety in gout: The LASSO study

ObjectivesAllopurinol is the most widely prescribed serum uric acid-lowering therapy (ULT) in gout. To achieve serum uric acid (sUA) concentrations associated with clinical benefit, allopurinol is serially uptitrated with sUA monitoring. Suboptimal dosing is a key contributor to poor clinical outcomes, but few data are available on the safety and efficacy of dose-titrated allopurinol, particularly at doses >300mg/d. The objective of this open-label study was to investigate the safety and efficacy of allopurinol under conditions where investigators were encouraged to titrate to optimal, medically appropriate doses. MethodsLong-term Allopurinol Safety Study Evaluating Outcomes in Gout Patients (LASSO) was a large, 6-month, multicenter study of allopurinol (NCT01391325). Adults meeting American Rheumatism Association Criteria for Classification of Acute Arthritis of Primary Gout and ≥2 gout flares in the previous year were eligible. Investigators were encouraged (but not required) to titrate allopurinol doses to achieve target sUA < 6.0mg/dL. The primary objective was evaluation of the safety of dose-titrated allopurinol by clinical and laboratory examinations at monthly visits. Secondary objectives included sUA-lowering efficacy and gout flare frequency. ResultsOf 1735 patients enrolled, 1732 received ≥1 allopurinol doses. The maximal daily allopurinol dose during study was <300mg in 14.4%, 300mg in 65.4%, and >300mg in 20.2% of patients; dosing duration was 115.5, 152.0, and 159.7 days, respectively. Overall, baseline demographic characteristics and comorbidity rates were similar across these three categories, but patients receiving >300-mg maximal dose had more severe gout. Treatment-emergent adverse events possibly related to allopurinol occurred in 15.2%, 9.5%, and 11.4% of patients in the <300-, 300-, and >300-mg categories, respectively. Rash incidence was low (1.5%) and allopurinol hypersensitivity syndrome was not reported. No clinically meaningful changes occurred in laboratory values. sUA < 6.0mg/dL at month 6 was achieved by 35.9% of patients overall: 22.4%, 35.0%, and 48.3% in dosing categories <300, 300, and >300mg, respectively. ConclusionsThis large multicenter study found that the allopurinol dose-titration strategy was well tolerated, without new safety signals emerging over 6 months. However, despite encouragement to treat to target, significant proportions of patients did not achieve target sUA.

Hyperuricemia - more than gout : Impact on cardiovascular risk and renal insufficiency

Hyperuricemia is not only associated with gout but also with hypertension, atherosclerosis and chronic kidney disease (CKD); however, in cases of disproportionally high serum uric acid levels without symptoms of gout and slowly progressive chronic kidney failure especially in young people, a genetic cause of hyperuricemia needs to be considered. The results of experimental studies suggest that hyperuricemia can be a pathophysiologically relevant cardiovascular risk factor. In animal studies hyperuricemia leads to oxidative stress and vascular dysfunction and chronically elevated uric acid levels can result in structural changes of the vessel wall. Epidemiological data show a connection between hyperuricemia and hypertension and uric acid lowering therapy has been shown to lower arterial blood pressure. In CKD, uric acid increases in parallel with the decline in GFR and an increase in proteinuria. Several ongoing prospective clinical trials will clarify if pharmacological lowering of uric acid will translate into reduction of relevant cardiovascular and renal endpoints. The treatment of gout and the medicinal prophylaxis of further gout attacks depend on the comorbidities and especially CKD.

Interleukin-1 as a therapeutic target in gout.

To give an overview of current evidence for interleukin (IL)-1 blockade in the management of gout. Three IL-1 blockers are currently available for clinical use: anakinra, rilonacept and canakinumab. Recent studies have focused on drugs with a long half-life: rilonacept and canakinumab. For treatment of acute gouty arthritis, three randomized controlled trials (RCTs) showed efficacy of canakinumab with some safety concerns and one RCT failed to show efficacy of rilonacept. For prevention of gout flare when starting uric acid lowering therapy (ULT), four RCTs showed efficacy of rilonacept and one RCT showed efficacy of canakinumab. There is sufficient evidence supporting the use of IL-1 blockers for treatment of acute gouty arthritis or for prevention of gout flares when starting ULT in selected patients, with contraindications or intolerance to conventional therapy. More data are needed to assess safety and to specify their use in routine practice.