Allopurinol therapy in gout patients does not associate with beneficial cardiovascular outcomes: a population-based matched-cohort study

Impact of gout on cardiovascular disease mortality: a meta-analysis

BACKGROUND

Several epidemiological studies have suggested that gout patients have a higher risk of cardiovascular disease mortality than healthy people. In contrast, the association between gout and cardiovascular disease (CVD) mortality was not obvious in other studies. In the present study, we aimed to investigate the relative risk for CVD mortality in gout patients in comparison to healthy controls.

METHODS

Literature published before March 2023 was searched in Google Scholar, PubMed, and the Web of Science. We summarized the impact of gout on CVD mortality with a meta-analysis. Hazard ratios (HRs) and 95% confidence intervals (CIs) regarding the impact of gout on CVD mortality were summarized with STATA 12.0 software.

RESULTS

Compared to individuals without gout, those with gout had higher mortality risks for CVD during follow-up, with a random effects model showing a risk of 1.30 (95% CI 1.15 to 1.48, p < 0.001; p-value for Cochran Q test < 0.001, I2 = 95.9%). Similarly, subjects with gout had a mortality risk of 1.28 (95% CI 1.12 to 1.46, p < 0.001; p-value for Cochran Q test = 0.050, I2 = 50.2%) for coronary heart disease (CHD) mortality during follow-up using the same statistical model. Furthermore, using a fixed effects model, individuals with gout had a mortality risk of 1.13 (95% CI 1.00 to 1.27, p = 0.049; p-value for Cochran Q test = 0.494, I2 = 0.0%) for myocardial infarction (MI) mortality during follow-up.

CONCLUSION

In conclusion, this meta-analysis provides evidence supporting a markedly increased mortality risk from CVD and CHD as well as MI in patients with gout relative to reference subjects without gout.

Atrial Fibrillation Risk and Urate-Lowering Therapy in Patients with Gout: A Cohort Study Using a Clinical Database

Individuals of Asian descent are at higher risk for developing hyperuricemia and gout as compared to Western populations. Urate-lowering therapy (ULT) is an effective treatment for hyperuricemia and gout. It was reported that febuxostat, one of the ULTs, raises the risk of atrial fibrillation (AF) in elderly populations. Nevertheless, this association has not been properly investigated in Asian populations. We aimed to investigate the development of AF after ULT with different drugs in an Asian population. We conducted a retrospective cohort study using the clinical database at Kaohsiung Veterans General Hospital. Patients newly diagnosed with gout between 1 January 2013 and 31 December 2020 and with a documented baseline serum uric acid (sUA) level but no prior diagnosis of AF were identified. Patients were divided into three groups-allopurinol, benzbromarone, and febuxostat users. During the follow-up period, the risks of incident AF following the initiation of ULT with different drugs were assessed. Development of incident AF was noted in 43 (6%) of the 713 eligible patients during the follow-up period (mean, 49.4 ± 26.6 months). Febuxostat-treated patients had a higher prevalence of certain comorbidities (diabetes mellitus, heart failure, and chronic kidney disease) and higher CHA2DS2-VASc scores. Compared with allopurinol, neither febuxostat nor benzbromarone was associated with increased adjusted hazard ratios (HR) for incident AF (HR: 1.20, 95% confidence interval [CI]: 0.43-3.34; HR: 0.68, 95% CI: 0.22-2.08). There was no difference in the risk of incident AF among Asian patients with gout who received febuxostat, allopurinol, or benzbromarone. Further studies are needed to evaluate long-term cardiovascular outcomes in patients receiving different ULT drugs.

Cardiovascular Risks in Korean Patients with Gout: Analysis Using a National Health Insurance Service Database

Although several epidemiologic studies have shown the association between gout and cardiovascular outcomes, specific risk factors for developing cardiovascular diseases in Asian patients with gout are undisclosed. Thus, the purpose of this study was to investigate risks of cardiovascular outcomes and its related factors in Korean patients with gout. This retrospective clinical study used sampled cohort data from the National Health Insurance Service in Korea. Patients with gout were defined as subjects enlisted with an ICD-10 code (M10). Control patients were selected by frequency matching for age, sex, and index year. Primary outcomes included ischemic heart disease (IHD), congestive heart failure, cerebrovascular disease (CVD), or transient ischemic attack. We calculated the hazard ratio (HR) using Cox regression, adjusting potential confounders including age, sex, lifestyle habits, laboratory results, and medication. We identified 3306 patients with gout and an equal number of matched controls. Multivariate Cox regression analysis showed that gout patients had increased risks of IHD (HR: 1.860, 95% CI: 1.446–2.392), acute myocardial infarction (HR: 3.246, 95% CI: 1.460–7.217), and CVD (HR: 1.552, 95% CI: 1.177–2.036). Old age, current smoking, frequent alcohol intake, high low-density lipoprotein, and diabetes mellitus increased the risk of cardiovascular outcomes, yet hypouricemic agents decreased the risk of cerebrovascular diseases. Our data corroborate that it is crucial to identify and manage traditional cardiovascular risk factors alongside lowering urate levels in patients with gout.

EULAR recommendations for cardiovascular risk management in rheumatic and musculoskeletal diseases, including systemic lupus erythematosus and antiphospholipid syndrome

OBJECTIVE

To develop recommendations for cardiovascular risk (CVR) management in gout, vasculitis, systemic sclerosis (SSc), myositis, mixed connective tissue disease (MCTD), Sjögren's syndrome (SS), systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS).

METHODS

Following European League against Rheumatism (EULAR) standardised procedures, a multidisciplinary task force formulated recommendations for CVR prediction and management based on systematic literature reviews and expert opinion.

RESULTS

Four overarching principles emphasising the need of regular screening and management of modifiable CVR factors and patient education were endorsed. Nineteen recommendations (eleven for gout, vasculitis, SSc, MCTD, myositis, SS; eight for SLE, APS) were developed covering three topics: (1) CVR prediction tools; (2) interventions on traditional CVR factors and (3) interventions on disease-related CVR factors. Several statements relied on expert opinion because high-quality evidence was lacking. Use of generic CVR prediction tools is recommended due to lack of validated rheumatic diseases-specific tools. Diuretics should be avoided in gout and beta-blockers in SSc, and a blood pressure target <130/80 mm Hg should be considered in SLE. Lipid management should follow general population guidelines, and antiplatelet use in SLE, APS and large-vessel vasculitis should follow prior EULAR recommendations. A serum uric acid level <0.36 mmol/L (<6 mg/dL) in gout, and disease activity control and glucocorticoid dose minimisation in SLE and vasculitis, are recommended. Hydroxychloroquine is recommended in SLE because it may also reduce CVR, while no particular immunosuppressive treatment in SLE or urate-lowering therapy in gout has been associated with CVR lowering.

CONCLUSION

These recommendations can guide clinical practice and future research for improving CVR management in rheumatic and musculoskeletal diseases.

Reduced Incidence of Stroke in Patients with Gout Using Benzbromarone

Gout is strongly associated with the incidence of atherosclerotic events, including stroke and myocardial infarction. Considering the increased prevalence of stroke in the population with gout, the aim of this study was to evaluate the effects of benzbromarone, a uricosuric agent, on the incidence of stroke in the population with gout. We used data from the Taiwanese National Health Insurance Registration Database (NHIRD). The benzbromarone user cohort included 15,143 patients; each patient was age- and sex-matched with one non-user randomly selected from the population with gout. Cox proportional hazard regression analysis was conducted to estimate the effects of benzbromarone on the incidence of stroke in the population with gout. The incidence of stroke was significantly lower in benzbromarone users than in benzbromarone non-users. The HR for the incidence of stroke was lower in male benzbromarone users than in non-users. An analysis of three age groups (<40, 40–59, and ≥60 years) indicated that the HRs in those aged 40–59 years and ≥60 years were significantly lower among benzbromarone users than non-users. In the population with gout, the incidence of stroke was lower in benzbromarone users than in benzbromarone non-users.

The Relationship between Uric Acid and the Development, Complication, and Prognosis of Atrial Fibrillation: The Views from a Clinical Study

A large number of studies suggest that uric acid (UA) is related to the occurrence, complications, and prognosis of atrial fibrillation (AF). However, the guidelines did not clearly elaborate on this issue. The current research results need to be summarized to analyze the association between UA and AF. This study found that in the current clinical research on the relationship between UA and AF, studies mainly focus on the development or complications of AF. A lot of repetitive work does not deepen awareness of this question. In contrast, studies investigating the effects of UA-lowering therapy on the management of AF are limited. The only reports deny the protective effect of UA-lowering therapy. For now, we suggest that UA is close to the occurrence and progression of AF; therefore, it may have important significance as a clinical marker. The role of UA-lowering therapy in the management of AF is one of the next key issues to be explored. It will be a meaningful topic to focus on the latest research on AF ablation and to conduct a secondary analysis to explore the prognostic impact of UA on the latest treatment methods for AF. Multiomics techniques may allow us to have a deeper understanding of the role of UA in AF management in the future.

The incidence and prevalence of cardiovascular diseases in gout: a systematic review and meta-analysis

The aims of this systematic review and meta-analysis were to describe prevalence of cardiovascular disease in gout, compare these results with non-gout controls and consider whether there were differences according to geography. PubMed, Scopus and Web of Science were systematically searched for studies reporting prevalence of any cardiovascular disease in a gout population. Studies with non-representative sampling, where a cohort had been used in another study, small sample size (< 100) and where gout could not be distinguished from other rheumatic conditions were excluded, as were reviews, editorials and comments. Where possible meta-analysis was performed using random-effect models. Twenty-six studies comprising 949,773 gout patients were included in the review. Pooled prevalence estimates were calculated for five cardiovascular diseases: myocardial infarction (2.8%; 95% confidence interval (CI)s 1.6, 5.0), heart failure (8.7%; 95% CI 2.9, 23.8), venous thromboembolism (2.1%; 95% CI 1.2, 3.4), cerebrovascular accident (4.3%; 95% CI 1.8, 9.7) and hypertension (63.9%; 95% CI 24.5, 90.6). Sixteen studies reported comparisons with non-gout controls, illustrating an increased risk in the gout group across all cardiovascular diseases. There were no identifiable reliable patterns when analysing the results by country. Cardiovascular diseases are more prevalent in patients with gout and should prompt vigilance from clinicians to the need to assess and stratify cardiovascular risk. Future research is needed to investigate the link between gout, hyperuricaemia and increased cardiovascular risk and also to establish a more thorough picture of prevalence for less common cardiovascular diseases.

Uricemia in the acute phase of myocardial infarction and its relation to long-term mortality risk

Aim: Although uric acid has antioxidant effects, hyperuricemia has been established as an indicator of increased cardiovascular mortality in various patient populations. Treatment of asymptomatic hyperuricemia in patients with acute myocardial infarction (MI) is not routinely recommended, and the efficacy of such treatment in terms of cardiovascular risk reduction remains doubtful. Materials & methods: In a prospective cohort study, we followed 5196 patients admitted for a MI between 2006 and 2018. We assessed the relationship between baseline uricemia and the incidence of all-cause death and cardiovascular mortality and the effect of long-term allopurinol treatment. Hyperuricemia was defined as serum uric acid >450 μmol/l in men and >360 μmol/l in women. Results: In the entire cohort, the 1-year all-cause and cardiovascular mortality rates were 8 and 7.4%, and the 5-year rates were 18.3 and 15.3%, respectively. Using a fully adjusted model, hyperuricemia was associated with a 70% increased risk of both all-cause death and cardiovascular mortality at 1 year, and the negative prognostic value of hyperuricemia persisted over the 5-year follow-up (for all-cause death, hazard risk ratio = 1.45 [95% CI: 1.23-1.70] and for cardiovascular mortality, hazard risk ratio = 1.52 [95% CI: 1.28-1.80], respectively). Treatment of asymptomatic hyperuricemia with allopurinol did not affect mortality rates. Conclusion: Hyperuricemia detected in patients during the acute phase of an MI appears to be independently associated with an increased risk of subsequent fatal cardiovascular events. However, hyperuricemia treatment with low-dose allopurinol did not prove beneficial for these patients.

Allopurinol and cardiovascular events: Time-related biases in observational studies

OBJECTIVE

Several observational studies reported that allopurinol, an effective treatment for gout, was associated with important reductions in cardiovascular events, with calls for large randomized trials, though some results were conflicting. We assessed the extent of time-related biases in these observational studies.

METHODS

We searched the literature for all observational studies reporting on allopurinol and cardiovascular events, focusing on two time-related biases. Time-related confounding bias results from studies using cohorts of patients all exposed to allopurinol, with comparisons based on episodes of allopurinol discontinuation, where confounding factors are not updated over follow-up time. Immortal time bias arises from the exposure misclassification of periods of cohort follow-up during which the outcome under study cannot occur.

RESULTS

We identified 12 studies, of which eight were affected by time-related confounding bias or immortal time bias, while the remaining four studies avoided these biases. The studies affected by time-related confounding bias resulted in significant reductions in the incidence of cardiovascular events with allopurinol use (pooled hazard ratio 0.88; 95% CI: 0.85-0.92), as did the studies affected by immortal time bias (pooled hazard ratio 0.79; 95% CI: 0.72-0.87). The four studies that avoided these biases resulted in a pooled hazard ratio of 1.07 (95% CI: 0.91-1.25).

CONCLUSIONS

Observational studies reporting significantly reduced incidence of cardiovascular events with allopurinol use were affected by time-related biases. Overall, studies that avoided these biases did not find a protective effect. The ALL-HEART randomised trial will provide important and accurate evidence on the potential effectiveness of allopurinol on cardiovascular outcomes.

The Role of Uric Acid in the Acute Myocardial Infarction: A Narrative Review

Increased serum uric acid (SUA) levels have been associated with various pathologic processes such as increased oxidative stress, inflammation, and endothelial dysfunction. Thus, it is not surprising that increased SUA is associated with various adverse outcomes including cardiovascular (CV) diseases. Recent epidemiological evidence suggests that increased SUA may be related to acute myocardial infarction (AMI). Accumulating data also showed that elevated UA has pathophysiological role in the development of AMI. However, there are also studies showing that SUA is not related to the risk of AMI. In this narrative review, we summarized the recent literature data regarding SUA and AMI after providing some background information for the association between UA and coronary artery disease. Future studies will show whether decreasing SUA levels is beneficial for outcomes related to AMI and the optimum SUA levels for best outcomes in CV diseases.

Increased Susceptibility of Atrial Fibrillation Induced by Hyperuricemia in Rats: Mechanisms and Implications

High levels of serum uric acid is closely associated with atrial fibrillation (AF); nonetheless, the detailed mechanisms remain unknown. Therefore, this work examined the intricate mechanisms of AF triggered by hyperuricemia and the impact of the uricosuric agent benzbromarone on atrial remodeling in hyperuricemic rats. After adjusting baseline serum uric acid levels, a total of 28 healthy male adult Sprague Dawley rats were randomly divided into 4 groups, namely, control (CTR), hyperuricemia (oxonic acid potassium salt, OXO) and benzbromarone (+ BBR), and OXO withdrawal groups. Primary rat cardiomyocytes were cultured with uric acid for 24 h to investigate the direct influence of uric acid on cardiomyocytes. Results revealed that AF vulnerability and AF duration were dramatically greater in hyperuricemic rats (OXO group), while the atrial effective refractory periods (AERPs) were significantly shorter. Meanwhile, BBR treatment and withdrawal of 2% OXO administration remarkably reduced AF inducibility and shortened AF duration. Moreover, abnormal morphology of atrial myocytes, atrial fibrosis, apoptosis, and substantial sympathetic nerve sprouting were observed in hyperuricemic rats. Apoptosis and fibrosis of atria were partly mediated by caspase-3, BAX, TGF-β1, and α-smooth muscle actin. Uric acid significantly induced primary rat cardiomyocyte apoptosis and fibrosis in vitro. Also, we found that sympathetic nerve sprouting was markedly upregulated in the atria of hyperuricemia rats, and was restored by BRB or absence of OXO administration. In summary, our study confirmed that AF induced by hyperuricemic rats occurred primarily via induction of atrial remodeling, thereby providing a novel potential treatment approach for hyperuricemia-related AF.

Comparative cardiovascular risk in users versus non-users of xanthine oxidase inhibitors and febuxostat versus allopurinol users

OBJECTIVES

The aim of this study is to determine major adverse cardiovascular events (MACE) and all-cause mortality comparing between xanthine oxidase inhibitors (XOIs) and non-XOI users, and between allopurinol and febuxostat.

METHODS

This is a retrospective cohort study of gout patients prescribed anti-hyperuricemic medications between 2013 and 2017 using a territory-wide administrative database. XOI users were matched 1:1 to XOI non-users using propensity scores. Febuxostat users were matched 1:3 to allopurinol users. Subgroup analyses were conducted based on colchicine use.

RESULTS

Of the 13 997 eligible participants, 3607 (25.8%) were XOI users and 10 390 (74.2%) were XOI non-users. After propensity score matching, compared with non-users (n = 3607), XOI users (n = 3607) showed similar incidence of MACE (hazard ratio [HR]: 0.997, 95% CI, 0.879, 1.131; P>0.05) and all-cause mortality (HR = 0.972, 95% CI 0.886, 1.065, P=0.539). Febuxostat (n = 276) users showed a similar risk of MACE compared with allopurinol users (n = 828; HR: 0.672, 95% CI, 0.416, 1.085; P=0.104) with a tendency towards a lower risk of heart failure-related hospitalizations (HR = 0.529, 95% CI 0.272, 1.029; P=0.061). Concurrent colchicine use reduced the risk for all-cause mortality amongst XOI users (HR = 0.671, 95% 0.586, 0.768; P<0.001).

CONCLUSION

In gout patients, XOI users showed similar risk of MACE and all-cause mortality compared with non-users. Compared with allopurinol users, febuxostat users showed similar MACE and all-cause mortality risks but lower heart failure-related hospitalizations.

Gout Is Prevalent but Under-Registered Among Patients With Cardiovascular Events: A Field Study

Objectives: Gout is an independent cardiovascular (CV) risk factor with significant morbidity and mortality. We aimed to estimate the prevalence of gout, characteristics and management in a hospitalized population for CV disease, a topic that remains to be defined. Methods: An observational, descriptive, cross-sectional study was carried out in patients admitted for CV events in the Cardiology, Neurology, and Vascular Surgery units of a tertiary center. Patients were selected following a non-consecutive, systematic sampling. Data about CV disease and gout were obtained from face-to-face interviews and patients' records. Gout diagnosis was established using the 2015 ACR/EULAR clinical classification criteria. The registration rate of gout was assessed by auditing patients' records and hospital discharge reports of CV events from the units of interest in the previous 2 years. To predict the presence of gout, multivariate logistic regression models were built to study the possible explanatory variables. Results: Two hundred and sixty six participants were recruited, predominantly males (69.9%) and Caucasians (96.6%) with a mean age of 68 years. Gout was identified in 40 individuals; thus, the prevalence was 15.0% (95% CI 10.9-19.2%). In 35% of cases, the diagnosis was absent from patients' records. Gout was found in 1.4-2.6% of hospital discharge reports of CV events, also indicating under-registration. The disease was long-standing, but with low reported rates of flares, involved joints, and tophi. At admission, only half of the gout patients were on urate-lowering therapy, being 38.5% of them on serum urate <6 mg/dl. The only independent predictor of gout was the existence of previous hyperuricemia (median serum urate in previous 5 years ≥7 mg/dl), with an odds ratio of 2.9 (95% CI 1.2-7.1); if hyperuricemia is not included in the model, the only independent predictor was chronic kidney disease (odds ratio 3.0; 95% CI 1.4-6.6). Conclusion: Gout is highly prevalent among patients admitted for CV events, with significant lack of awareness and suboptimal management, despite being a well-established independent CV risk factor.

Cardiovascular safety risks associated with gout treatments

INTRODUCTION

Uric acid is the final byproduct of purine metabolism. The loss of the enzyme that hydrolyzes uric acid to allantoin was lost, leading to a decrease in uric acid excretion and its further accumulation. The buildup of uric acid leads to damage in different organ systems, including the cardiovascular system. With the increasing burden of cardiovascular disease worldwide, a growing body of evidence has addressed the relationship between urate, cardiovascular outcomes, and gout medication cardiovascular safety. Areas covered: We discuss the most common gout therapies used for the reduction of serum urate and management of gout flares in different observational and clinical trials and their effects on different aspects of cardiovascular disease. We selected the most representative clinical studies that evaluated cardiovascular outcomes with each gout therapy as well as recommendation given by the most representative guidelines from Rheumatology societies for the management of gout.

EXPERT OPINION

The treatment of gout reduces joint damage and it can also lessen CV morbidity. Allopurinol shows CV safety profile when compared to other ULTs. Evidence supporting CV safety with the use of colchicine and IL-1 agents is promising and research needs to be conducted to further assess this outcome.

[Hyperuricemia, gout and high cardiovascular risk - how to manage them in clinical practice]

In recent years, the relationship of hyperuricemia and gout with a high risk of cardiovascular disease has been widely discussed. Therefore, it is important to systematically examine patients in order to diagnose comorbidities, among which cardiovascular disease and its complications occupy a leading place and consider mandatory treatment of patients with hyperuricemia and gout with high cardiovascular risk with lowering drugs, which fully reflects the provisions of the latest European recommendations for the management and treatment of patients with gout.

Risk of Acute Myocardial Infarction Among New Users of Allopurinol According to Serum Urate Level: A Nested Case-Control Study

Objectives: To test the hypothesis that allopurinol reduces the risk of acute myocardial infarction (AMI) in hyperuricemic patients and to assess whether the effect is dependent on dose, duration and serum uric acid (SUA) level attained after treatment. Methods: Nested case-control study over the period 2002–2015. From a cohort of patients aged 40–99 years old, we identified incident AMI cases and randomly selected five controls per case, matched for exact age, sex and index date. Adjusted odds ratios (AOR) and 95% CI were computed through unconditional logistic regression. Only new users of allopurinol were considered. Results: A total of 4697 AMI cases and 18,919 controls were included. Allopurinol use was associated with a reduced risk of AMI mainly driven by duration of treatment (AOR ≥180 days = 0.71; 95% CI: 0.60–0.84). Among long-term users (≥180 days), the reduced risk was only observed when the SUA level attained was below 7 mg/dL (AOR_{<6 mg/dL} = 0.64; 95% CI: 0.49–0.82; AOR_6–7mg/dL = 0.64; 95%CI:0.48-0.84); AOR_>7mg/dL = 1.04; 95% CI: 0.75–1.46; p for trend = 0.001). A dose-effect was observed but faded out once adjusted for the SUA level attained. The reduced risk of AMI occurred in both patients with gout and patients with asymptomatic hyperuricemia. Conclusions: The results confirm a cardioprotective effect of allopurinol which is strongly dependent on duration and SUA level attained after treatment.

Cardiovascular Disease in Gout and the Protective Effect of Treatments Including Urate-Lowering Therapy

Cardiovascular disease affects more than 90 million Americans. Recent studies support an increased cardiovascular disease risk in inflammatory conditions, such as gout. Increased serum urate levels, or hyperuricemia, are a precursor to gout. Data from meta-analyses have shown hyperuricemia to be linked to hypertension and coronary heart disease. Similarly, gout has been associated with an increased risk of myocardial infarction, cerebrovascular accidents, and death from cardiovascular disease in randomized clinical trials. Urate-lowering therapy reduces serum urate and may decrease systemic inflammation, generation of oxidative species, and reverses endothelial dysfunction through hyperuricemia-dependent or hyperuricemia-independent pathways. Cardioprotective benefits of allopurinol, a first-line agent for the treatment of gout, have been demonstrated to potentially prevent myocardial infarction, stroke, atrial fibrillation, and other cardiovascular diseases in observational studies in select populations. Randomized controlled trials (RCTs) have also examined the role of newer urate-lowering therapies, such as febuxostat and lesinurad, and their risk of cardiovascular-specific mortality in comparison to allopurinol. A large post-marketing study of febuxostat vs. allopurinol showed higher all-cause and cardiovascular-specific mortality in the febuxostat group than in the allopurinol group; a major study limitation was that large numbers of patients were lost to follow-up or discontinued treatment. RCTs are required to assess the comparative effectiveness of urate-lowering therapies, validate findings of observational studies, and to determine which subgroup populations of gout are most likely to benefit from appropriate long-term urate-lowering therapy. This review examines the data for increased cardiovascular disease in gout and potential underlying mechanisms (including hyperuricemia, inflammation, endothelial dysfunction, oxidative stress) and the effect of urate-lowering therapy on cardiovascular disease.

Allopurinol use associated with increased risk of acute myocardial infarction in older people in a case-control study

Objective

There is controversy about the association between the allopurinol use and the risk of acute myocardial infarction. The aim of the study was to examine the association between allopurinol use and acute myocardial infarction in older people in Taiwan.

Materials and Methods

We used the 2000-2013 database of the Taiwan National Health Insurance Program to conduct a case-control study. Cases were assigned as subjects aged 65 years and older with the first incident acute myocardial infarction. Matched controls were assigned as subjects aged 65 years and older without any type of coronary artery disease. Ever use of allopurinol was defined as subjects who had at least a prescription of allopurinol before the diagnosis date of first incident acute myocardial infarction. The odds ratio (OR) and the 95% confidence interval (CI) for acute myocardial infarction associated with allopurinol use were estimated by the multivariable logistic regression model.

Results

There were 4701 cases with the first incident acute myocardial infarction and 9369 matched controls. The adjusted OR of acute myocardial infarction was 2.2 (95% CI 1.7- 2.7) for subjects with ever use of allopurinol, compared with never use. The adjusted ORs of acute myocardial infarction were 2.0 (95% CI 1.5-2.6) for subjects with average daily dosage of allopurinol <200 mg and 2.5 (95% CI 1.6-4.0) for subjects with average daily dosage of allopurinol ≥200 mg.

Conclusion

Allopurinol use is associated with increased odds of acute myocardial infarction in older people, which is dosage dependent.

Association between allopurinol and cardiovascular outcomes and all-cause mortality in diabetes: A retrospective, population-based cohort study

AIM

To assess the association between allopurinol and mortality and cardiovascular outcomes in an allopurinol-treated diabetes cohort.

MATERIALS AND METHODS

We conducted a population-based retrospective cohort study in Ontario, Canada. Eligible subjects were ≥ 66 years old with diabetes and a first prescription for allopurinol between 1 April, 2002 and 31 March, 2012 and were followed until 31 March, 2016. The primary outcome was a composite: all-cause mortality, non-fatal cardiovascular event (myocardial infarction, revascularization procedure, or stroke) or congestive heart failure (CHF). Secondary outcomes were components of the primary outcome and pneumonia as a negative tracer. Allopurinol was modelled as time-varying exposed versus unexposed, daily dose category and cumulative dose using sex-specific multivariable Cox proportional hazards models.

RESULTS

Over a median follow-up of 4.65 years (interquartile range 1.79-7.81), 16 266/23 103 males and 10 571/15 313 females experienced the primary outcome. Allopurinol was associated with a reduction in the primary outcome [adjusted hazard ratios (aHR) 0.77 (95% confidence interval 0.75-0.80) and 0.81 (0.78-0.84) for males and females, respectively], driven by marked reductions in all-cause mortality and modest reductions in cardiovascular events/CHF. There was no effect of cumulative allopurinol dose on any outcome, and allopurinol was also associated with reduced risk of pneumonia in males [aHR 0.88 (0.83, 0.93)].

CONCLUSIONS

Allopurinol was associated with reduced mortality and cardiovascular outcomes. However, lack of cumulative dose effect and a positive tracer outcome in males suggests residual bias. Future research assessing whether allopurinol prevents vascular complications in diabetes requires a clinical trial.

Hyperuricemia treatment in acute heart failure patients does not improve their long-term prognosis: A propensity score matched analysis from the AHEAD registry

BACKGROUND

Hyperuricemia is associated with a poorer prognosis in heart failure (HF) patients. Benefits of hyperuricemia treatment with allopurinol have not yet been confirmed in clinical practice. The aim of our work was to assess the benefit of allopurinol treatment in a large cohort of HF patients.

METHODS

The prospective acute heart failure registry (AHEAD) was used to select 3160 hospitalized patients with a known level of uric acid (UA) who were discharged in a stable condition. Hyperuricemia was defined as UA ≥500 μmoL/L and/or allopurinol treatment at admission. The patients were classified into three groups: without hyperuricemia, with treated hyperuricemia, and with untreated hyperuricemia at discharge. Two- and five-year all-cause mortality were defined as endpoints. Patients without hyperuricemia, unlike those with hyperuricemia, had a higher left ventricular ejection fraction, a better renal function, and higher hemoglobin levels, had less frequently diabetes mellitus and atrial fibrillation, and showed better tolerance to treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and/or beta-blockers.

RESULTS

In a primary analysis, the patients without hyperuricemia had the highest survival rate. After using the propensity score to set up comparable groups, the patients without hyperuricemia had a similar 5-year survival rate as those with untreated hyperuricemia (42.0% vs 39.7%, P = 0.362) whereas those with treated hyperuricemia had a poorer prognosis (32.4% survival rate, P = 0.006 vs non-hyperuricemia group and P = 0.073 vs untreated group).

CONCLUSION

Hyperuricemia was associated with an unfavorable cardiovascular risk profile in HF patients. Treatment with low doses of allopurinol did not improve the prognosis of HF patients.

Urate-lowering therapy alleviates atherosclerosis inflammatory response factors and neointimal lesions in a mouse model of induced carotid atherosclerosis

Hyperuricemia (HU) is a cause of gout. Clinical studies show a link between HU and cardiovascular disease. However, the role of soluble serum urate (SU) on atherosclerosis development remains elusive. We aimed to use a new HU mouse model [Uricase/Uox knockout (KO)] to further investigate the relationship between HU and atherosclerosis. A mouse model by perivascular collar placement of induced carotid atherosclerosis was established in male Uox-KO mice. The Uox-KO mice had elevated SU levels and enhanced levels of atherosclerosis inflammatory response proteins. In contrast, Uox-KO mice with carotid atherosclerosis showed severe neointimal changes in histology staining consistent with increases in intimal area and increases in proliferating cell nuclear antigen (PCNA)- and F4/80-positive cells. Allopurinol reduced neointimal areas induced by the perivascular collar in hyperuricemic mice, accompanied by decreased expression of PCNA- and F4/80-positive cells. Urate-lowering treatment alleviated atherosclerosis inflammatory response factors and reactive oxygen species (ROS) intensities in both collar placement Uox-KO mice and urate-stimulated human umbilical vein endothelial cells (HUVECs). In vitro results using HUVECs showed ROS was induced by urate and ROS induction was abrogated using antioxidants. These data demonstrate that urate per se does not trigger atherosclerosis intima lesions in male mice. Urate worsens carotid neointimal lesions induced by the perivascular collar and urate-lowering therapy partially abrogates the effects. The current study warrants clinical studies on the possible benefits of urate-lowering therapy in atherosclerosis patients with HU.

Is increased uric acid a risk factor or a defensive response? The Campania Salute Network

BACKGROUND AND AIMS

Circulating uric acid (UA) is positively associated with body mass index (BMI), blood glucose, blood pressure (BP), markers of inflammation, and altered lipid profile. UA has also anti-oxidative properties which might be beneficial for cardiovascular (CV) system. It is still debated whether or not UA is independently associated with increased CV morbidity and/or mortality.

METHODS AND RESULTS

We studied prognostic impact of UA in 8833 hypertensive adults (mean age 53 ± 12 yrs, 3857 women) from the Campania Salute Network, without prevalent CV disease and more than stage 3 CKD. We calculated standardized UA Z-score, adjusted for age, sex, glomerular filtration rate, and BMI. Low and high UA and UA Z-score quartiles were compared to the 2 middle quartiles assumed to be "normal". Prevalence of obesity and diabetes was higher in low and high than in normal UA Z-score group (all p < 0.001). Systolic BP, left ventricular mass, carotid intima thickness were significantly higher and ejection fraction was reduced in the presence of high UA Z-score (all p < 0.001). Over 33-months average follow-up, incident major CV end-points (MACE) were not significantly different among low, normal and high UA or UA Z-score. In the latter analysis, however, incident MACE tended to be more frequent in the low than the high UA Z-score. Despite the results of multivariable analyses, the effect of less aggressive therapy in low UA Z-score cannot be excluded with certainty.

CONCLUSION

In treated hypertensive patients, high levels of UA normalized for major biological determinants do not independently predict CV outcome. CLINICALTRIALS.

GOV IDENTIFIER

NCT02211365.

Case-control study examining the association between allopurinol use and ischemic cerebrovascular disease

Few studies focus on the relationship between allopurinol and ischemic cerebrovascular disease. The goal of the study was to investigate the association of long-term therapy of allopurinol with the first-time attack of ischemic cerebrovascular disease in Taiwan. We performed a case-control study using the database of the Taiwan National Health Insurance Program. The case group included 14,937 subjects aged 20-84 years with the first-time attack of ischemic cerebrovascular disease from 2000 to 2013. The control group included 14,937 sex-matched and age-matched subjects aged 20-84 years without any type of cerebrovascular disease. Ever use of allopurinol was defined as subjects who had at least a prescription for allopurinol before the index date. The OR and the 95% CI for ischemic cerebrovascular disease associated with allopurinol use were measured by the multivariable logistic regression model. The adjusted OR of ischemic cerebrovascular disease was 0.992 (95% CI 0.989 to 0.996) for subjects with increasing cumulative duration of allopurinol use for every 1 month, compared with never use. In a further analysis, the adjusted OR of ischemic cerebrovascular disease was 0.74 (95% CI 0.57 to 0.96) for cumulative duration of allopurinol use >3 years, compared with never use. Our findings suggest that lone-term therapy of allopurinol >3 years is associated with decreased risk of the first-time attack of ischemic cerebrovascular disease, compared with no allopurinol therapy.

Positive association between hypertension and urinary bladder cancer: epidemiologic evidence involving 79,236 propensity score-matched individuals

INTRODUCTION

We hypothesized that hypertensive patients harbor a higher risk of urinary bladder (UB) cancer.

MATERIAL AND METHODS

We performed a population-based cohort study on adults using a National Health Insurance Research Database (NHIRD) dataset. Hypertension and comparison non-hypertensive (COMP) groups comprising 39,618 patients each were propensity score-matched by age, sex, index date, and medical comorbidities. The outcome was incident UB cancer validated using procedure codes. We constructed multivariable Cox models to derive adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Cumulative incidence was compared using a log-rank test.

RESULTS

During a total follow-up duration of 380,525 and 372,020 person-years in the hypertension and COMP groups, 248 and 186 patients developed UB cancer, respectively, representing a 32% increase in the risk (aHR, 1.32; 95% CI, 1.09-1.60). Hypertensive women harbored a significantly increased risk of UB cancer (aHR, 1.55; 95% CI, 1.12-2.13) compared with non-hypertensive women, whereas men with hypertension had a statistically non-significant increased risk (aHR, 1.22; 95% CI, 0.96-1.55). The sensitivity analysis demonstrated that the increased risk was sustained throughout different follow-up durations for the entire cohort; a statistical increase in the risk was also noted among hypertensive men.

CONCLUSION

This nationwide population-based propensity score-matched cohort study supports a positive association between hypertension and subsequent UB cancer development.

Allopurinol and endothelial function: A systematic review with meta-analysis of randomized controlled trials

Aim

Oxidative stress and endothelial dysfunction are two inter‐related conditions commonly seen in patients with cardiovascular risk factors. The enzyme, xanthine oxidase, is an important contributor to these phenomena but to a variable degree in different patient populations. This meta‐analysis will summarize the effect of allopurinol, an established xanthine oxidase inhibitor, on endothelial function among patients with different comorbidities.

Methods

Medline Complete, PubMed, ProQuest, ClinicalKey, Wiley Online Library, and Cochrane Central Register of Controlled Trials were searched till July 29, 2017. Meta‐analysis was planned for randomized controlled trials (RCTs) that investigated allopurinol effects on endothelial function. A random effect model was used to calculate the standardized mean difference (with 95% confidence intervals: CI) as an estimate of effect size. Heterogeneity was quantified by four types of information: Q statistics, I² statistic, Tau‐squared (T²), and Tau (T).

Results

Thirty eligible studies were identified; 12 were included in the final analysis and subdivided among 3 patient’s groups: patients with chronic heart failure (CHF; 197 patients), patients with chronic kidney disease (CKD; 183 patients), and patients with type 2 diabetes mellitus (DM; 170 patients). Allopurinol was found to have a statistically significant benefit on endothelial function in patients with CHF and CKD but not in type 2 DM. The standardized mean differences and CI in the three patient’s groups were 0.776 (0.429, 1.122), 0.350 (0.009, 0.690), and 1.331 (−0.781, 3.444), respectively.

Conclusion

Allopurinol has an antioxidant property that might partially reverse endothelial dysfunction in patients with certain comorbidities. The importance of this property and the magnitude of the beneficial effect are likely to be related to the relative contribution of xanthine oxidase into the oxidative stress associated with different underlying pathologies.

Gout as a risk factor for osteoporosis: epidemiologic evidence from a population-based longitudinal study involving 108,060 individuals

Is gout a risk factor for future osteoporosis? This large population-based study comprising two matched groups of individuals with and without gout demonstrates that patients with gout have a 20% increase in the risk of developing osteoporosis in future through an 8-year follow-up.

INTRODUCTION

To examine if gout is associated with an increased risk of osteoporosis.

METHODS

We conducted a nationwide population-based retrospective matched-cohort study. Two matched cohorts (n = 36,458 with gout and 71,602 without gout) assembled and recruited from the Longitudinal Health Insurance Dataset containing 1 million subjects. Exclusion criteria were missing data, age < 20 years, short follow-up period, and pre-existing osteoporosis. Both cohorts were followed up until incident osteoporosis, death, or the end of the study. Person-year data and incidence rates were evaluated. A multivariable Cox model was used to derive an adjusted hazard ratio (aHR) after controlling for socioeconomic proxy, geographical difference, glucocorticoid and allopurinol exposure, various prespecified medical conditions, and comorbidities.

RESULTS

Men comprised 72.8% of the cohorts. With a follow-up of 183,729 and 359,900 person-years for the gout and non-gout cohorts, 517 and 811 incidents of osteoporosis occurred, respectively, after excluding osteoporosis incidents in the first 3 years of follow-up. The cumulative incidence of osteoporosis was statistically higher in the gout cohort than in the non-gout cohort, at 3.3 versus 2.1% (P = 0.0036, log-rank). Our Cox model showed a 1.2-fold increase in the incidence of osteoporosis in the gout cohort, with an aHR of 1.2 (95% confidence interval, 1.06-1.35).

CONCLUSIONS

This first population-based epidemiologic study supports the hypothesis that compared with individuals without gout; those with gout have a modest increase in the risk of developing osteoporosis in future.

Effect of hydrochlorothiazide on serum uric acid concentration: a genome-wide association study

AIM

To recognize genetic associations of hydrochlorothiazide-induced change in serum uric acid (SUA) concentration.

PATIENTS & METHODS

We conducted a genome-wide association study on hydrochlorothiazide-induced change in SUA in 214 Finnish men from the GENRES study. Replication analyses were performed in 465 Finns from the LIFE study.

RESULTS

In GENRES, we identified 31 loci associated with hydrochlorothiazide-induced change in SUA at p < 5 × 10^-5. rs1002976 near VEGFC associated with the change in GENRES and in LIFE. rs950569 near BRINP3 associated with the change in SUA in GENRES and LIFE. The analysis of previously reported SNPs and candidate genes provided some proof for PADI4 and ABCC4.

CONCLUSION

We report genetic markers that may predict the increase in SUA concentration during thiazide treatment.

Allopurinol and the risk of incident peripheral arterial disease in the elderly: a US Medicare claims data study

Objective

The aim was to examine whether allopurinol use is independently associated with a reduction in the risk of incident peripheral arterial disease (PAD) in the US elderly.

Methods

We used the 5% random Medicare sample from 2006 to 2012 to examine the association of allopurinol use and duration of use with the risk or hazard of incident PAD in a retrospective cohort study using a new user design. Multivariable Cox regression models adjusted for demographics, co-morbidity, cardiac medications and cardiac conditions. Hazard ratios (HRs) and 95% CIs were calculated.

Results

We identified 26 985 episodes of incident allopurinol use in 25 282 beneficiaries; 3167 allopurinol use episodes (12%) ended in incident PAD. In multivariable-adjusted analyses, allopurinol use was associated with an HR of 0.88 (95% CI: 0.81, 0.95) for incident PAD, as was female gender, HR 0.84 (95% CI: 0.78, 0.90). In a separate multivariable-adjusted model, compared with no allopurinol use, longer durations of allopurinol use were associated with lower HR of PAD: 181 days to 2 years, 0.88 (95% CI: 0.79, 0.97); and >2 years, 0.75 (95% CI: 0.63, 0.89). Other factors significantly associated with a higher HR of PAD were age 75 to < 85 and ⩾85 years, higher Charlson index score and black race. Sensitivity analyses that adjusted for cardiac conditions and medications confirmed these findings, with minimal to no attenuation of HRs.

Conclusion

New allopurinol use was independently associated with a lower risk of PAD in the elderly. Longer allopurinol use durations seemed more protective. Mechanisms of the protective effect need to be investigated in future studies.

Cardiovascular effects of urate-lowering therapies in patients with chronic gout: a systematic review and meta-analysis

Objectives

To determine if urate-lowering treatment (ULT) in gout can reduce cardiovascular (CV) outcomes.

Methods

Randomized trials were searched for treatment with ULT in gout. Eligible trials had to report CV safety of a ULT. Potential medications included allopurinol, febuxostat, pegloticase, rasburicase, probenecid, benzbromarone, sulphinpyrazone, losartan, fenofibrate and sodium-glucose linked transporter 2 inhibitors.

Results

A total of 3084 citations were found, with 642 duplicates. After the primary screen, 35 studies were selected for review. Several trials did not report CV events. Six were not randomized controlled trials (RCTs). Four studies reported no events in either intervention arm while the other four had 40 events in the febuxostat group ( n = 3631) and 5 in allopurinol group ( n = 1154). Overall, the pooled analysis did not show a significant difference between the two [febuxostat vs allopurinol: relative risk (RR) 1.69 (95% CI 0.54, 5.34), P = 0.37]. CV events did not decrease over time. Comparing shorter studies (<52 weeks) to longer ones did not reveal any statistical differences. However, in long-term studies with febuxostat vs allopurinol, results were nearly significant, with more CVE occurring with febuxostat treatment. Comparing any ULT to placebo (eight studies, n = 2221 patients) did not demonstrate a significant difference in non-Anti-Platelet Trialists' Collaboration events [any ULT vs placebo: RR 1.47 (95% CI 0.49, 4.40), P = 0.49] or all-cause mortality [any ULT vs placebo: RR 1.45 (95% CI 0.35, 5.77), P = 0.60].

Conclusion

RCT data do not suggest differences in CV events among ULTs in gout. Trials had few events despite high-risk patients being enrolled and may have been too short to show CV reduction by controlling inflammatory attacks and lowering uric acid.

Impact of comorbidities on gout and hyperuricaemia: an update on prevalence and treatment options

Gout, the most prevalent inflammatory arthritis worldwide, is associated with cardiovascular and renal diseases, and is an independent predictor of premature death. The frequencies of obesity, chronic kidney disease (CKD), hypertension, type 2 diabetes, dyslipidaemias, cardiac diseases (including coronary heart disease, heart failure and atrial fibrillation), stroke and peripheral arterial disease have been repeatedly shown to be increased in gout. Therefore, the screening and care of these comorbidities as well as of cardiovascular risk factors are of outmost importance in patients with gout. Comorbidities, especially CKD, and drugs prescribed for their treatment, also impact gout management. Numerous epidemiological studies have shown the association of asymptomatic hyperuricaemia with the above-mentioned diseases and cardiovascular risk factors. Animal studies have also produced a mechanistic approach to the vascular toxicity of soluble urate. However, causality remains uncertain because confounders, reverse causality or common etiological factors might explain the epidemiological results. Additionally, these uncertainties remain unsolved despite recent studies using Mendelian randomisation or therapeutic approaches. Thus, large randomised placebo-controlled trials are still needed to assess the benefits of treating asymptomatic hyperuricaemia.

Critical revision of the medical treatment of gout in Brazil

Gout is considered the most common form of inflammatory arthritis in men over 40 years. The authors present a brief review of the current treatment of gout and discuss the existing pharmacological limitations in Brazil for the treatment of this disease. Although allopurinol is still the main drug administered for decreasing serum levels of uric acid in gout patients in this country, the authors also present data that show a great opportunity for the Brazilian drug market for the treatment of hyperuricemia and gout and especially for patients using private and public (SUS) health care systems.

Cardiovascular risk of patients with gout seen at rheumatology clinics following a structured assessment

OBJECTIVES

Gout-associated cardiovascular (CV) risk relates to comorbidities and crystal-led inflammation. The aim was to estimate the CV risk by prediction tools in new patients with gout and to assess whether ultrasonographic carotid changes are present in patients without high CV risk.

METHODS

Cross-sectional study. Consecutive new patients with crystal-proven gout underwent a structured CV consultation, including CV events, risk factors and two risk prediction tools-the Systematic COronary Evaluation (SCORE) and the Framingham Heart Study (FHS). CV risk was stratified according to current European guidelines. Carotid ultrasound (cUS) was performed in patients with less than very high CV risk. The presence of carotid plaques was studied depending on the SCORE and FHS by the area under the curve (AUC) of receiver operating curves.

RESULTS

237 new patients with gout were recruited. CV stratification by scores showed a predominance of very high (95 patients, 40.1%) and moderate (72 patients, 30.5%) risk levels. cUS was performed in 142 patients, finding atheroma plaques in 66 (46.5%, 95% CI 37.8 to 54.2). Following cUS findings, patients classified as very high risk increased from 40.1% up to 67.9% (161/237 patients). SCORE and FHS predicted moderately (AUC 0.711 and 0.683, respectively) the presence of atheroma plaques at cUS.

CONCLUSIONS

The majority of patients presenting with gout may be at very high CV risk, indicating the need for initiating optimal prevention strategies at this stage. Risk prediction tools appear to underestimate the presence of carotid plaque in patients with gout.

Allopurinol reduces the risk of myocardial infarction (MI) in the elderly: a study of Medicare claims

BACKGROUND

Previous observational studies that have examined the association of allopurinol with myocardial infarction (MI) have provided contradictory results. One study showed that allopurinol reduced the risk, while another study showed an increased risk with allopurinol. Therefore, our objective was to assess whether allopurinol use is associated with a reduction in the risk of MI in the elderly.

METHOD

We used the 2006-2012 5 % random sample of Medicare beneficiaries to study the association of new allopurinol initiation and the risk of incident MI in a cohort study. Multivariable-adjusted Cox regression models adjusted for age, gender, race, and Charlson index, in addition to various cardio-protective medications (beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, diuretics, statins). We calculated hazard ratios (HRs) with 95 % confidence intervals (CIs). Sensitivity analyses adjusted for coronary artery disease (CAD) risk factors, including hypertension, hyperlipidemia, diabetes, and smoking.

RESULTS

Of the 29,298 episodes of incident allopurinol use, 1544 were associated with incident MI (5.3 % episodes). Allopurinol use was associated with reduced hazards of MI, with a HR of 0.85 (95 % CI, 0.77 to 0.95). Compared to no allopurinol use, longer durations of allopurinol use were associated with a lower HR of MI: 1-180 days, 0.98 (95 % CI, 0.84 to 1.14); 181 days to 2 years, 0.83 (95 % CI, 0.72 to 0.95); and >2 years, 0.70 (95 % CI, 0.56 to 0.88). Other factors associated with a higher hazard of MI were: age 75 to <85 years and ≥85 years, male gender, higher Charlson index score, and the use of an ACE inhibitor. Adjustment for CAD risk factors confirmed these findings.

CONCLUSION

Incident allopurinol use was associated with a reduction in the risk of incident MI in the elderly. Longer durations of allopurinol use reduced the risk of incident MI incrementally. Future studies should assess the underlying mechanisms for MI prevention and assess the risk-benefit ratio for allopurinol use.

Allopurinol and the risk of stroke in older adults receiving medicare

BACKGROUND

Previous studies of allopurinol and stroke risk have provided contradictory findings, ranging from a protective effect to an increased risk. Our objective was to assess whether allopurinol use is associated with the risk of stroke in the elderly.

METHODS

We used the 5 % random sample of Medicare beneficiaries from 2006-2012 to study the association of new allopurinol initiation and incident stroke. We used multivariable-adjusted Cox regression models adjusted for age, gender, race, Charlson index, and cardio-protective medications (beta-blockers, ACE inhibitors, diuretics, statins) to calculate hazards ratio (HR) with 95 % confidence intervals (CI). Sensitivity analyses adjusted for coronary artery disease (CAD) risk factors including hypertension, hyperlipidemia, diabetes, and smoking instead of Charlson index.

RESULTS

Among 28,488 eligible episodes of incident allopurinol, 2,177 ended in incident stroke (7.6 % episodes). In multivariable-adjusted analyses, allopurinol use was associated with 9 % lower hazard ratio for stoke, 0.91 (95 % CI, 0.83 to 0.99). Compared to no allopurinol use, allopurinol use durations of 181 days to 2 years, 0.88 (95 % CI, 0.78 to 0.99) and >2 years, 0.79 (95 % CI, 0.65 to 0.96) were significantly associated with lower multivariable-adjusted hazard of stroke. Sensitivity analyses adjusted for CAD risk factors confirmed these findings. In subgroup analyses, significant associations were noted between allopurinol use and the risk of ischemic stroke, 0.89 (95 % CI, 0.81 to 0.98); associations were not significant for hemorrhagic stroke, 1.01 (95 % CI, 0.79 to 1.29).

CONCLUSIONS

Allopurinol use is associated with lower risk of stroke overall, more specifically ischemic stroke. This association is evident after 6-months of allopurinol use, and the hazard reduction increases with longer duration of use. Future studies need to examine underlying mechanisms.

Risk of Autoimmune Disease in Adults with Chronic Insomnia Requiring Sleep-Inducing Pills: A Population-Based Longitudinal Study

BACKGROUND

Recent studies indicate that chronic insomnia is associated with the development of certain somatic diseases. Whether it would be associated with the development of an autoimmune disease (AID) was unknown.

OBJECTIVE

We aimed to examine the association and quantify the magnitude of risk for AID in individuals suffering from chronic insomnia requiring sleep-inducing pills.

DESIGN

This was a population-based, nationwide longitudinal study.

PARTICIPANTS

Using a claims data set containing 1 million randomly sampled, insured subjects derived from the National Health Insurance Research Database, we assembled a chronic insomnia group and a 1:3 propensity score-matched comparison group (CP), which were balanced in terms of sex, age, insurance premium, urbanization, alcohol use disorder, smoking-related diagnoses, and morbid obesity.

MAIN MEASURES

Person-time data with incidence rate, adjusted hazard ratios (aHR) by the Cox model, AID-free survival functions compared with the log-rank test, and a sensitivity analysis on the time lag effect were presented. Incident AID within the first year of follow-up were excluded. The error rate was controlled using the Benjamini-Hochberg procedure.

KEY RESULTS

With 39,550 and 129,914 person-years' follow-up for the chronic insomnia and CP groups (n = 5,736 and 17,208), respectively, we found an increased risk for subsequent AID, representing a 70 % increase in the aHR (1.7; 95 % confidence interval [CI], 1.5-1.9, p < 0.0001). A positive association between chronic insomnia and primary Sjögren's syndrome (pSS) was observed (aHR, 1.3; 95 % CI, 1.1-1.6). Sensitivity analysis disclosed that AID risk was even stronger after 5 years of follow-up (aHR, 2.0; 95 % CI, 1.7-2.4).

CONCLUSION

Chronic insomnia requiring sleep-inducing pills may be associated with a 70 % increased risk for future AID, particularly pSS.

2016 updated EULAR evidence-based recommendations for the management of gout

Background

New drugs and new evidence concerning the use of established treatments have become available since the publication of the first European League Against Rheumatism (EULAR) recommendations for the management of gout, in 2006. This situation has prompted a systematic review and update of the 2006 recommendations.

Methods

The EULAR task force consisted of 15 rheumatologists, 1 radiologist, 2 general practitioners, 1 research fellow, 2 patients and 3 experts in epidemiology/methodology from 12 European countries. A systematic review of the literature concerning all aspects of gout treatments was performed. Subsequently, recommendations were formulated by use of a Delphi consensus approach.

Results

Three overarching principles and 11 key recommendations were generated. For the treatment of flare, colchicine, non-steroidal anti-inflammatory drugs (NSAIDs), oral or intra-articular steroids or a combination are recommended. In patients with frequent flare and contraindications to colchicine, NSAIDs and corticosteroids, an interleukin-1 blocker should be considered. In addition to education and a non-pharmacological management approach, urate-lowering therapy (ULT) should be considered from the first presentation of the disease, and serum uric acid (SUA) levels should be maintained at<6 mg/dL (360 µmol/L) and <5 mg/dL (300 µmol/L) in those with severe gout. Allopurinol is recommended as first-line ULT and its dosage should be adjusted according to renal function. If the SUA target cannot be achieved with allopurinol, then febuxostat, a uricosuric or combining a xanthine oxidase inhibitor with a uricosuric should be considered. For patients with refractory gout, pegloticase is recommended.

Conclusions

These recommendations aim to inform physicians and patients about the non-pharmacological and pharmacological treatments for gout and to provide the best strategies to achieve the predefined urate target to cure the disease.

Allopurinol and the risk of atrial fibrillation in the elderly: a study using Medicare data

OBJECTIVE

To assess the effect of allopurinol use on the risk of incident atrial fibrillation (AF) in the elderly.

METHODS

We used the 5% random Medicare Claims data from 2006 to 2012 to examine the association of allopurinol use and incident AF in a cohort of patients with an absence of AF at baseline (at least 365 days). Multivariable-adjusted Cox regression analyses compared allopurinol exposed and non-exposed periods for the risk of AF, controlling for age, sex, race, Charlson-Romano comorbidity index and use of statins, diuretics, ACE inhibitors and β-blockers. HR with 95% CIs was calculated. Sensitivity analyses considered a longer baseline period (365 days vs 183 days) and individual comorbidities.

RESULTS

There were 9244 episodes of incident allopurinol use in 8569 beneficiaries, of which 1366 episodes (14.8%) had incident AF. In multivariable-adjusted analyses, allopurinol use was associated with an HR of 0.83 (95% CI 0.74 to 0.93) for incident AF. In a separate multivariable-adjusted model, compared with no allopurinol use, longer allopurinol use durations were associated with a lower HR of AF: 180 days-2 years, 0.85 (95% CI 0.73 to 0.99) and >2 years, 0.65 (95% CI 0.52 to 0.82). Other factors significantly associated with a higher hazard of AF were: age 75-<85 years and ≥85 years, higher Charlson index score and current β-blocker use. Sensitivity analyses confirmed these findings with minimal/no attenuation of HRs.

CONCLUSIONS

Allopurinol use was associated with a reduced risk of incident AF in the elderly, especially its use for >6 months duration. Future studies should assess the mechanisms underlying this beneficial effect of allopurinol.

Effect of Allopurinol on Cardiovascular Outcomes in Hyperuricemic Patients: A Cohort Study

BACKGROUND

Hyperuricemia and gout have been associated with increased cardiovascular risk. Allopurinol is an effective urate-lowering drug. Whether lowering of urate by allopurinol improves the cardiovascular risk in hyperuricemic patients remains to be established.

OBJECTIVE

Our objective was to investigate the effect of allopurinol on cardiovascular outcomes in hyperuricemic patients in an observational setting.

METHODS

We had access to a study population consisting of all patients from Funen County, Denmark with high urate levels (≥6 mg/dL) from 1992 to 2010. We linked 4 registries; all blood samples, all in- and outpatient contacts in hospitals, all reimbursed prescriptions and causes of death. We identified all incident allopurinol users and matched them 1:1 to nonusers of urate-lowering therapy, with similar urate levels, by using propensity scores. Hazard ratios were calculated using competing risk regression model, with respect to Antiplatelet Trialists' Collaboration composite outcome (myocardial infarction, stroke, or cardiovascular death) and all-cause mortality.

RESULTS

Among 65,971 patients with hyperuricemia, we found 7127 patients on allopurinol treatment. In the propensity score-matched cohort we found a hazard ratio of 0.89 (95% confidence interval, 0.81-0.97) for the main outcome among allopurinol treated compared with nonusers of allopurinol. The corresponding hazard ratio for all-cause mortality was 0.68 (95% confidence interval, 0.62-0.74).

CONCLUSION

Allopurinol treatment is associated with a decreased cardiovascular risk among hyperuricemic patients.

Risk and clinical predictors of osteoporotic fracture in East Asian patients with chronic obstructive pulmonary disease: a population-based cohort study

INTRODUCTION

Osteoporosis is becoming an impending epidemic in the Asia-Pacific region. The association between risk of osteoporotic fracture (OTPF) and chronic obstructive pulmonary disease (COPD) in East Asian patients is yet to be fully examined. We conducted a nationwide population-based retrospective cohort study of 98,700 patients aged ≥50 years with or without COPD using a national administrative claims dataset.

MATERIALS AND METHODS

The patients were divided into COPD and comparison groups comprising 19,740 and 78,960 patients, respectively. The groups were 1 to 4 matched for age, gender, index date, diabetes mellitus, pre-existing osteoporosis and chronic kidney disease. Information such as the geographic area where southern part represented more sunshine exposure, smoking-related diagnoses, alcohol use disorder, whether there was regular use of inhaled corticosteroids and oral corticosteroids, vitamin D prescriptions, Charlson-Deyo comorbidity index score, and other relevant medical comorbidities were extracted for analysis. They were followed up until OTPF or the end of the year 2013. The outcome measure was an osteoporotic vertebral fracture and other long-bone fractures. A multivariate Cox model was constructed to derive adjusted hazard ratios (aHR) for OTPF with corresponding 95% confidence intervals (CI) after controlling for age, sex, insurance premium category, vitamin D prescription, osteoporosis, and coronary heart disease (CHD). Kaplan-Meier curves of the probability of OTPF-free survival for each cohort were compared using the log-rank test. Patients with OTPF during the first follow-up year were excluded from the overall risk calculation. Contributing factors to the increased risk of OTPF in COPD patients were examined in a sensitivity analysis.

RESULTS

After a total follow-up of 68,743 patient-years for the COPD group and 278,051 patient-years for the matched comparison group, the HR for OTPF was 1.24 (95% CI [1.02-1.51]; P = 0.0322) in COPD patients. The aHR was increased by 30% for vertebral OTPF (aHR = 1.297, 95% CI [1.020-1.649]; P = 0.0339). Differential lag time sensitivity analysis revealed a progressively elevated risk up to 8-fold increase in women (aHR = 8.0 (95% CI [1.81-35.4]; P < 0.01)) during the fifth follow-up year. COPD patients with pre-existing osteoporosis or given vitamin D prescription harbor a sustained increased risk up to the 5th (aHR, 4.1; 95% CI [1.61-10.35]) and third (aHR, 2.97; 95% CI [1.48-5.97]) follow-up year, respectively.

CONCLUSIONS

Our nationwide population-based cohort study demonstrates that East Asian COPD patients aged 50 and beyond do harbor a modestly increased risk for osteoporotic vertebral fractures particularly for those who are female, have pre-existing osteoporosis or require vitamin D prescription.

Effect of Urate-Lowering Therapy on All-Cause and Cardiovascular Mortality in Hyperuricemic Patients without Gout: A Case-Matched Cohort Study

Objectives

An increased risk of mortality in patients with hyperuricemia has been reported. We examined (1) the risk of all-cause and cardiovascular disease (CVD) mortality in untreated hyperuricemic patients who did not receive urate-lowering therapy (ULT), and (2) the impact of ULT on mortality risk in patients with hyperuricemia.

Methods

In this retrospective case-matched cohort study during a mean follow-up of 6.4 years, 40,118 Taiwanese individuals aged ≥17 years who had never used ULT and who had never had gout were examined. The mortality rate was compared between 3,088 hyperuricemic patients who did not receive ULT and reference subjects (no hyperuricemia, no gout, no ULT) matched for age and sex (1:3 hyperuricemic patients/reference subjects), and between 1,024 hyperuricemic patients who received ULT and 1,024 hyperuricemic patients who did not receive ULT (matched 1:1 based on their propensity score and the index date of ULT prescription). Cox proportional hazard modeling was used to estimate the respective risk of all-cause and CVD (ICD-9 code 390–459) mortality.

Results

After adjustment, hyperuricemic patients who did not receive ULT had increased risks of all-cause (hazard ratio, 1.24; 95% confidence interval, 0.97–1.59) and CVD (2.13; 1.34–3.39) mortality relative to the matched reference subjects. Hyperuricemic patients treated with ULT had a lower risk of all-cause death (0.60; 0.41–0.88) relative to hyperuricemic patients who did not receive ULT.

Conclusion

Under-treatment of hyperuricemia has serious negative consequences. Hyperuricemic patients who received ULT had potentially better survival than patients who did not.

Hyperuricemia, gout, and cardiovascular disease: an update

Across the globe, both gout and hyperuricemia have become increasingly common over the last few decades. The burden of gouty disease is made heavier by its association with several comorbid conditions, including hypertension, cardiovascular disease, and chronic kidney disease. Accruing evidence from prospective studies suggests that gout is an independent risk factor for developing cardiovascular disease and for higher cardiovascular mortality. While asymptomatic hyperuricemia does not seem to be an independent risk factor for cardiovascular disease, increasing data implicates hyperuricemia as a risk factor for developing incidental hypertension. Important questions that remain unanswered include whether addressing asymptomatic hyperuricemia forestalls the onset of hypertension, and whether treating gout with urate-lowering agents improves cardiovascular outcomes. This article reviews the most recent data regarding the relationship between hyperuricemia, gout, hypertension, and cardiovascular disease, as well as emerging evidence as to whether treatment of hyperuricemia and gout improves cardiovascular outcomes.

Uric acid and coronary artery disease: An elusive link deserving further attention

Uric acid is the final product of purine metabolism. Classically it is recognized as the cause of gouty arthritis and kidney stones. Western civilization has increased serum levels of uric acid which is no longer considered a benign plasma solute. It has been postulated and recently demonstrated that it can penetrate cell membrane and exerts damaging intracellular actions such as oxidation and inflammation. These observations have stimulated several epidemiological researches suggesting that hyperuricemia is linked or even provokes hypertension and coronary artery disease. In this review we summarize the current evidences regarding uric acid which contribute in the pathophysiology of coronary artery disease.