Serum uric acid level and risk for peripheral arterial disease: analysis of data from the multiple risk factor intervention trial

Hyperuricaemia Prevalence Rates According to Their Physiochemical and Epidemiological Diagnostic Criteria and Their Associations with Cardio-Renal-Metabolic Factors: SIMETAP-HU Study

Background: Scientific societies disagree on serum uric acid (SUA) thresholds for the diagnosis of hyperuricaemia (HU) according to epidemiological or physiochemical criteria (SUA ≥ 7.0 mg/dL for men and ≥6.0 mg/dL for women [HU-7/6]; SUA ≥ 7.0 mg/dL for both genders [HU-7/7], respectively). HU is not included among the diagnostic criteria for metabolic syndrome or cardiovascular-renal-metabolic syndrome (CKM), although it promotes atherosclerosis and is associated with renal and cardiometabolic diseases. Both issues are of utmost importance and need to be clarified, hence the present study aims to assess the prevalence rates of HU and their associations with CKM factors. Methods: A cross-sectional observational study was conducted on a random population-based sample of 6489 adults. Bivariate and multivariate analyses were performed on the most well-known renal and cardiometabolic variables of the populations with and without HU-7/7 and HU-7/6. Results: The adjusted prevalence rates for HU-7/6 were 13.4% in adult population (18.4% in men; 9.6% in women) and 10.2% (18.4% in men; 3.8% in women) for HU-7/7. The main factors associated independently with HU for both genders were low estimated glomerular filtration rate, hypertension, hypertriglyceridaemia, and alcoholism, regardless of the criteria chosen, as well as albuminuria in women and central obesity in men. Conclusions: The prevalence rates of HU increase linearly with age for both genders. The associations of CKM factors with HU diagnosed according to physiochemical criterion are more similar between men and women than those using epidemiological criteria.

Preliminary study on the material basis and mechanism underlying uric acid reduction by Thlaspi arvense L

ETHNOPHARMACOLOGICAL RELEVANCE

In the Tibetan region of China, Thlaspi arvense L. is utilized for the prevention and treatment of hyperuricemia (HUA). Thlaspi arvense has been shown to lower uric acid levels in HUA rats in preliminary studies. However, the active components and mechanisms that account for its therapeutic effects remain elusive.

AIM OF STUDY

Network pharmacology, ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS), mRNA-sequencing, and quantitative reverse transcription PCR (RT-PCR) were used to investigate the active ingredients of Thlaspi arvense against HUA in rats and elucidate the underlying mechanisms in this study.

MATERIALS AND METHODS

A HUA rat model was established by a combination of intraperitoneal injection of potassium oxonate and intragastric administration of yeast extract. In the control and model groups, gastric gavage was performed to administer a normal saline solution, 4.5 mg kg-1 benzbromarone in the positive drug group, and 3.5 g kg-1Thlaspi arvense in the Thlaspi arvense group. After which network pharmacology and UPLC-Q-TOF-MS were employed to explore the active ingredients underlying the lowering of uric acid in Thlaspi arvense. In addition, mRNA-sequencing, network pharmacology and RT-PCR were applied to uncover Thlaspi arvense's mechanism of uric acid reduction.

RESULTS

The results showed that a two-week administration of the effective constituents of Thlaspi arvense led to a significant improvement in HUA rats, including lower serum levels of uric acid (UA), xanthine oxidase (XOD), creatinine (CREA), carbamide (UREA), aspartate aminotransferase (AST), alanine transaminase (ALT), and liver tissue activities of XOD, ADA, super (MDA). A network pharmacological analysis revealed 40 active compounds, including organic acids and flavonoids, that act on HUA therapeutic targets. These targets primarily focus on pathways related to uric acid metabolism modulation, such as XOD, SLC22A12, ABCG2, SLC22A8, and others, reducing HUA. The analysis of mRNA-sequencing as well as RT-PCR data from renal tissue demonstrated that the targets modulating uric acid metabolism were SLC22A8, SLC12A1, and SLC16A7.

CONCLUSION

In summary, organic acids and flavonoids may be the active components in Thlaspi arvense that alleviate HUA. The principal mechanisms are as follows: inhibition of XOD activity in the serum to reduce uric acid production, regulation of renal reabsorption and secretion of uric acid to increase uric acid excretion, and alleviation of oxidative stress reaction to decrease systemic damage and, eventually, treatment of HUA.

Hyperuricemia as a Risk Factor in Hypertension among Patients with Very High Cardiovascular Risk

Hypertension remains a global threat to public health, affecting the worldwide population. It is one of the most common risk factors for cardiovascular disease. Today's treatments focus on creating a hypotensive effect. However, there is a constant search for additional factors to reduce the potential of developing hypertension complications. These factors may act as a parallel treatment target with a beneficial effect in specific populations. Some studies suggest that uric acid may be considered such a factor. This study investigated the potential effect of uric acid concentrations over 5 mg/dL on the incidence of hypertension complications among patients with very high cardiovascular risk. A total of 705 patients with hypertension and very high cardiovascular risk were selected and included in the analysis. The patients were divided and compared according to serum uric acid levels. The study showed a higher occurrence of heart failure (OR = 1.7898; CI: 1.2738-2.5147; p = 0.0008), atrial fibrillation (OR = 3.4452; CI: 1.5414-7.7002; p = 0.0026) and chronic kidney disease (OR = 2.4470; CI: 1.3746-4.3558; p = 0.0024) among individuals with serum uric acid levels over 5 mg/dL, males and those with a BMI > 25 kg/m2. These findings suggest that even serum uric acid concentrations over 5 mg/dL may affect the prevalence of hypertension-related complications among patients with very high cardiovascular risk.

Comparative Effectiveness of Sodium-Glucose Cotransporter-2 Inhibitors for Recurrent Gout Flares and Gout-Primary Emergency Department Visits and Hospitalizations : A General Population Cohort Study

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT2is) decrease serum urate levels, but whether this translates into prevention of recurrent flares among patients with gout and gout-primary emergency department (ED) visits or hospitalizations is unknown.

OBJECTIVE

To compare gout flares and cardiovascular events among patients with gout initiating SGLT2is versus dipeptidyl peptidase 4 inhibitors (DPP-4is), another second-line glucose-lowering agent not associated with serum urate levels or cardiovascular risk.

DESIGN

Propensity score-matched, new-user cohort study.

SETTING

General population database from 1 January 2014 to 30 June 2022.

PARTICIPANTS

Patients with gout and type 2 diabetes.

MEASUREMENTS

The primary outcome was recurrent gout flare counts ascertained by ED, hospitalization, outpatient, and medication dispensing records. Secondary outcomes included myocardial infarction and stroke; genital infection (positive control) and osteoarthritis encounter (negative control) were also assessed. Poisson and Cox proportional hazards regressions were used with 1:1 propensity score matching (primary analysis) and overlap weighting (sensitivity analysis).

RESULTS

After propensity score matching, the flare rate was lower among SGLT2i initiators than DPP-4i initiators (52.4 and 79.7 events per 1000 person-years, respectively), with a rate ratio (RR) of 0.66 (95% CI, 0.57 to 0.75) and a rate difference (RD) of -27.4 (CI, -36.0 to -18.7) per 1000 person-years. The corresponding RR and RD for gout-primary ED visits and hospitalizations were 0.52 (CI, 0.32 to 0.84) and -3.4 (CI, -5.8 to -0.9) per 1000 person-years, respectively. The corresponding hazard ratio (HR) and RD for myocardial infarction were 0.69 (CI, 0.54 to 0.88) and -7.6 (CI, -12.4 to -2.8) per 1000 person-years; the HR for stroke was 0.81 (CI, 0.62 to 1.05). Those who initiated SGLT2is showed higher risk for genital infection (HR, 2.15 [CI, 1.39 to 3.30]) and no altered risk for osteoarthritis encounter (HR, 1.07 [CI, 0.95 to 1.20]). Results were similar when propensity score overlap weighting was applied.

LIMITATION

Participants had concurrent type 2 diabetes.

CONCLUSION

Among patients with gout, SGLT2is may reduce recurrent flares and gout-primary ED visits and hospitalizations and may provide cardiovascular benefits.

PRIMARY FUNDING SOURCE

National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Differences in the Association Between Alcoholic Beverage Type and Serum Urate Levels Using Standardized Ethanol Content

IMPORTANCE

Differences have been observed in the association of serum urate levels with consumption of different types of alcoholic beverages. However, previous studies have not standardized the unit of intake for ethanol content, and only limited types of alcoholic beverages have been evaluated.

OBJECTIVE

To examine differences in the association of serum urate levels with various types of alcoholic beverages when their intakes are standardized for ethanol content.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cross-sectional study was conducted using data from participants aged 20 years or older who completed a medical checkup at St Luke's International University in Japan between October 1, 2012, and October 31, 2021. Participant demographics, blood test results, and lifestyle questionnaire data were used as covariates. Analysis was performed in December 2021.

EXPOSURES

Consumption of alcoholic beverages, including beer, sake (rice wine), shochu (Japanese spirit), wine, and whiskey.

MAIN OUTCOMES AND MEASURES

Serum urate levels were measured during the medical checkup. The beverage unit was standardized to 1 standard drink, which contained 20 g of ethanol. Multivariable linear regression including interaction terms of alcohol consumption and dominant alcoholic beverage was performed.

RESULTS

This study included 78 153 participants. Their mean (SD) age was 47.6 (12.8) years; 36 463 (46.7%) were men and 41 690 were women (53.3%). A total of 45 755 participants (58.5%) were regular alcohol drinkers. Consistent associations of serum urate levels with alcohol consumption were observed in the beer-dominant group, with β coefficients (for 1 standard drink per day) of 0.14 mg/dL (95% CI, 0.11-0.17 mg/dL; P < .001) for men and 0.23 mg/dL (95% CI, 0.20-0.26 mg/dL; P < .001) for women. A moderate increase in serum urate levels was observed in the wine-dominant group compared with a modest and nonsignificant increase in the sake-dominant group, with β coefficients (for 1 standard drink per day) for the latter group of 0.05 mg/dL (95% CI, -0.01 to 0.10; P = .10) for men and 0.04 mg/dL (95% CI, -0.05 to 0.14 mg/dL; P = .38) for women. Restricted cubic splines showed different patterns in associations of serum urate levels with ethanol intake by dominant alcoholic beverages.

CONCLUSIONS AND RELEVANCE

The results of this study suggest that the extent of the association of serum urate levels with alcohol intake was different for alcoholic beverages even after ethanol content was standardized. Higher beer consumption among men and women was consistently associated with higher serum urate levels, whereas sake was not associated with changes in serum urate levels. Therefore, alcoholic beverage type, in addition to ethanol content, should be considered as a factor contributing to hyperuricemia.

Excess comorbidities in gout: the causal paradigm and pleiotropic approaches to care

Gout is a common hyperuricaemic metabolic condition that leads to painful inflammatory arthritis and a high comorbidity burden, especially cardiometabolic-renal (CMR) conditions, including hypertension, myocardial infarction, stroke, obesity, hyperlipidaemia, type 2 diabetes mellitus and chronic kidney disease. Substantial advances have been made in our understanding of the excess CMR burden in gout, ranging from pathogenesis underlying excess CMR comorbidities, inferring causal relationships from Mendelian randomization studies, and potentially discovering urate crystals in coronary arteries using advanced imaging, to clinical trials and observational studies. Despite many studies finding an independent association between blood urate levels and risk of incident CMR events, Mendelian randomization studies have largely found that serum urate is not causal for CMR end points or intermediate risk factors or outcomes (such as kidney function, adiposity, metabolic syndrome, glycaemic traits or blood lipid concentrations). Although limited, randomized controlled trials to date in adults without gout support this conclusion. If imaging studies suggesting that monosodium urate crystals are deposited in coronary plaques in patients with gout are confirmed, it is possible that these crystals might have a role in the inflammatory pathogenesis of increased cardiovascular risk in patients with gout; removing monosodium urate crystals or blocking the inflammatory pathway could reduce this excess risk. Accordingly, data for CMR outcomes with these urate-lowering or anti-inflammatory therapies in patients with gout are needed. In the meantime, highly pleiotropic CMR and urate-lowering benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors and key lifestyle measures could play an important role in comorbidity care, in conjunction with effective gout care based on target serum urate concentrations according to the latest guidelines.

C-reactive Protein, Free Fatty Acid, and Uric Acid as Predictors of Adverse Events after Endovascular Revascularization of Arterial Femoropopliteal Occlusion Lesions

OBJECTIVES

This study aimed to investigate the relationship between pre-procedure high-sensitivity C-reactive protein (hsCRP), free fatty acid (FFA), and uric acid (UA) levels and post-procedure mortality and morbidity of endovascular revascularization of arterial femoropopliteal occlusion lesions.

METHODS

This was a retrospective review of clinical data retrieved from a prospectively held database in Peking Union Medical College Hospital. A total of 71 Patients who underwent endovascular treatment (EVT) for femoropopliteal occlusive disease between January 1, 2014 and November 1, 2017, were included in this study. Endpoints were defined as major adverse limb events (MALE; target vessel revascularization, amputation, or disease progression) and major adverse cardiovascular events (MACE; stroke, myocardial infarction, or all-cause death) during the entire follow-up period. Univariate and multivariate Cox proportional hazards regression models were used to evaluate the relationship of elevated biomarker levels (hsCRP, FFA and UA, measured by immunoturbidimetry assay, enzymatic assay and enzymatic assay, respectively) to MALE and MACE outcomes.

RESULTS

Seventy-one patients (72 limbs) with sufficient follow-up information were included in the analysis. The mean age was 69.7 ± 8.6 years; 21.1% were female. The Rutherford class of target limbs were ≥ 3. The median follow-up was 36 (range 18-59 months). Univariate analyses revealed that patients with elevated hsCRP levels had an increased risk of MALE (hazard ratio [HR], 2.682; 95% confidence interval [CI], 1.281-5.617, P = 0.009). High FFA levels were associated with an increased risk of MALE (HR, 2.658; 95% CI, 1.075-6.573; P = 0.034). Multivariate analyses demonstrated that elevated hsCRP values (HR, 4.015; 95% CI, 1.628-10.551; P = 0.003) and FFA value (HR, 3.034; 95% CI, 1.102-8.354; P = 0.032) were both significantly associated with increased MALE. Elevated UA levels predicted MACE in the presence of confounders (HR, 11.446; 95% CI, 1.367-95.801 P = 0.023).

CONCLUSION

Pre-procedure hsCRP and FFA levels could serve as predictors of adverse events after EVT in patients with arterial femoropopliteal occlusive disease. The role of UA in MACE may warrant further investigation, because the correlation is not as powerful as the other two in the study.

Associations of Serum Uric Acid Levels With Macrovascular and Renal Microvascular Dysfunction Among Individuals From Sub-Saharan Africa

IMPORTANCE

Serum uric acid (SUA) level is associated with vascular dysfunction in Eurasian populations, but little is known about this association in individuals from sub-Saharan Africa, who have a high prevalence of both relatively high SUA levels and vascular dysfunction.

OBJECTIVES

To assess the associations of SUA levels with macrovascular and kidney microvascular dysfunction in individuals of sub-Saharan African ancestry and evaluate potential factors that could mediate these associations.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional analyses of baseline data from the multicenter Research on Obesity and Diabetes Among African Migrants study, conducted from 2012 to 2015, were performed from January to March 2021. The population included Ghanaian individuals living in Ghana and Europe.

EXPOSURE

Abnormal SUA levels.

MAIN OUTCOMES AND MEASURES

Logistic regression was used to examine the associations of SUA level quartiles with microvascular (albuminuria) and macrovascular (peripheral artery disease and coronary artery disease) dysfunction, with adjustments for age, sex, estimated glomerular filtration rate, site of residence, socioeconomic status, alcohol, smoking, diabetes, hypertension, waist-hip ratio, and total cholesterol level. Mediation analysis was performed to assess whether the association was via elevated blood pressure, hemoglobin A1c, and high-sensitivity C-reactive protein levels or via weight-hip ratio. The research questions were formulated after data collection.

RESULTS

A total of 4919 Ghanaian individuals (3047 [61.9%] women) aged 25-75 years (mean [SD], 46.26 [11.08] years) were included. There was a significant positive association between SUA quartiles and albuminuria, but not coronary artery disease or peripheral artery disease, after adjustment for covariates. After full adjustment, individuals in the fourth SUA quartile had higher odds of albuminuria (adjusted odds ratio [aOR], 1.54; 95% CI, 1.07-2.21), but not peripheral artery disease (aOR, 1.35; 95% CI, 0.87-2.08) or coronary artery disease (aOR, 1.09; 95% CI, 0.77-1.55), compared with individuals in the first quartile. After full adjustment, systolic and diastolic blood pressure significantly mediated the association between SUA concentrations and albuminuria, accounting for 19.4% of the total association for systolic and 17.2% for diastolic blood pressure; hemoglobin A1c, high-sensitivity C-reactive protein, and waist-hip ratio did not mediate this association.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study among a sub-Saharan African population, elevated SUA levels were significantly associated with kidney microvascular dysfunction and mediated partly through elevated blood pressure. These findings suggest that individuals from sub-Saharan Africa with elevated SUA levels may benefit from periodic screening for kidney microvascular dysfunction to aid early detection or treatment.

The Impact of Uric Acid and Hyperuricemia on Cardiovascular and Renal Systems

The description of gout dates back almost 5000 years, and scientific interest in uric acid increased when it was found to be involved in the pathogenesis of gout. Since then, many basic and clinical studies have assessed the implications of uric acid for the oxidative system, inflammation, and cardiovascular and renal outcomes. Uric acid-lowering therapy failed to improve clinical hard outcomes in asymptomatic hyperuricemia, and it is retained in symptomatic hyperuricemia. Dietary and lifestyle modifications are critical to manage hyperuricemia. More studies are warranted to investigate the role of uric acid-lowering drugs on cardiovascular outcomes.

The role of diet in hyperuricemia and gout

PURPOSE OF REVIEW

Although gout's cardinal feature is inflammatory arthritis, it is closely associated with insulin resistance and considered a manifestation of the metabolic syndrome. As such, both gout and hyperuricemia are often associated with major cardiometabolic and renal comorbidities that drive the persistently elevated premature mortality rates among gout patients. To that end, conventional low-purine (i.e., low-protein) dietary advice given to many patients with gout warrant reconsideration.

RECENT FINDINGS

Recent research suggests that several healthy diets, such as the Mediterranean or Dietary Approaches to Stop Hypertension (DASH) diets, in combination with weight loss for those who are overweight or obese, can drastically improve cardiometabolic risk factors and outcomes. By treating gout as a part of the metabolic syndrome and shifting our dietary recommendations to these healthy dietary patterns, the beneficial effects on gout endpoints should naturally follow for the majority of typical gout cases, mediated through changes in insulin resistance.

SUMMARY

Dietary recommendations for the management of hyperuricemia and gout should be approached holistically, taking into consideration its associated cardiometabolic comorbidities. Several healthy dietary patterns, many with similar themes, can be tailored to suit comorbidity profiles and personal preferences.

Cardiovascular events in hyperuricemia population and a cardiovascular benefit-risk assessment of urate-lowering therapies: a systematic review and meta-analysis

BACKGROUND

Hyperuricemia and gout have become public health concerns; many important guidelines have recommended xanthine oxidase inhibitors (XOIs) as the first-line urate-lowering therapies (ULTs) to treat chronic gout with hyperuricemia. However, whether treating hyperuricemia and gout with ULTs modifies cardiovascular risks remains controversial. The aim of this study was to assess the incident risk of cardiovascular (CV) events (CVE) in hyperuricemia population, assess the cardiovascular benefit-risk of ULTs in hyperuricemia patients with or without gout in diverse cardiovascular risk sub-groups, and specify the safety of different ULTs.

METHODS

We searched PubMed, Embase, the Cochrane Library, Wanfang, Chongqing VIP (CQVIP, en.cqvip.com), and China National Knowledge Infrastructure Database for prospective cohort studies and randomized controlled trials (RCTs) in English and Chinese. Potential medications included XOIs, and uricosurics. RCTs were divided into sub-groups analysis based on blinding status and patients' history of CV diseases. Risk ratios (RRs) were calculated and were reported with corresponding 95% confidence intervals (CIs) by fixed-effects or random-effects model.

RESULTS

Seven prospective cohort studies and 17 RCT studies were included. The risks of both major adverse cardiovascular events (MACE) (RR = 1.72, 95% CI 1.28-2.33) and CVE (RR = 1.35, 95% CI 1.12-1.62) were higher in the hyperuricemia population than non-hyperuricemia one. In seven RCT studies where XOIs were compared with no-treatment or placebo, the results of five low CV risk studies showed that XOIs lowered the risks of both MACE (RR = 0.35, 95% CI 0.20-0.62) and CVE (RR = 0.61, 95% CI 0.44-0.85); whereas two high CV risk studies showed that XOIs lowered the risk of CVE (RR = 0.69, 95% CI 0.54-0.88) rather than MACE (RR = 0.62, 95% CI 0.29-1.35). In nine RCT studies where the cardiovascular safety between febuxostat and allopurinol were compared, no statistical difference was found in the risk of MACE or CVE.

CONCLUSIONS

The hyperuricemia population does have a higher incidence of CVE, and the results suggested that XOIs might reduce the incidence of MACE and total CVE. In addition, from the perspective of cardiovascular safety, febuxostat equaled allopurinol in our meta-analysis.

The Association of Hyperuricemia and Gout With the Risk of Cardiovascular Diseases: A Cohort and Mendelian Randomization Study in UK Biobank

Background

The association between hyperuricemia/gout with cardiovascular diseases (CVD) have been investigated. However, whether the magnitude of associations differs between hyperuricemia and gout, and the causality of these associations, remains inconclusive.

Methods

Based on UK Biobank, we conducted a cohort analysis including 431,967 participants, who were categorized as gout, hyperuricemia, and normal groups at recruitment, and followed up for CVD until December 2019. The phenotypic association of hyperuricemia/gout with CVD was estimated by Cox regression, adjusting for multiple confounders. Further exploration on the causality of such links was performed using Mendelian Randomization (MR) analysis, where we selected exclusive genetic variants for hyperuricemia and for gout based on summary GWAS data from independent populations.

Results

During mean 10.20 years of follow-up, hyperuricemia patients were associated with increased CVD (HR = 1.33, 95% CI: 1.29-1.36), compared to individuals who were free of hyperuricemia/gout. The risk elevation was even higher for gout patients (HR = 1.54, 95% CI: 1.48-1.62). Furthermore, we found significantly positive association between genetic liability for hyperuricemia and CVD in both one-sample (OR = 1.06, 95% CI: 1.02-1.11) and two-sample (OR = 1.09, 95% CI: 1.03-1.16) MR analysis. However, genetic liability for gout was not associated with CVD (OR = 0.89, 95% CI: 0.79-1.01 in one-sample, and OR = 0.92, 95% CI: 0.82-1.21 in two-sample MR analysis).

Conclusion

Individuals with hyperuricemia/gout were at increased risk of various types of CVD. As the MR analyses suggest a causal effect of hyperuricemia, but not gout, on CVD, these results indicate the possible effects of other gout-associated factors on the development of CVD, in addition to the uric acid pathway.

Pharmacologic Management of Gout in Patients with Cardiovascular Disease and Heart Failure

Gout is the most common inflammatory arthritis and is often comorbid with cardiovascular disease (CVD). Hyperuricemia and gout are also independent risk factors for cardiovascular events, worsening heart failure (HF), and death. The recommended treatment modalities for gout have important implications for patients with CVD because of varying degrees of cardiovascular and HF benefit and risk. Therefore, it is critical to both manage hyperuricemia with urate-lowering therapy (ULT) and treat acute gout flares while minimizing the risk of adverse cardiovascular events. In this review, the evidence for the safety of pharmacologic treatment of acute and chronic gout in patients with CVD and/or HF is reviewed. In patients with CVD or HF who present with an acute gout flare, colchicine is considered safe and potentially reduces the risk of myocardial infarction. If patients cannot tolerate colchicine, short durations of low-dose glucocorticoids are efficacious and may be safe. Nonsteroidal anti-inflammatory drugs should be avoided in patients with CVD or HF. The use of canakinumab and anakinra for acute gout flares is limited by the high cost, risk of serious infection, and relatively modest clinical benefit. For long-term ULT, allopurinol, and alternatively probenecid, should be considered first-line treatments in patients with CVD or HF given their safety and potential for reducing cardiovascular outcomes. An increased risk of cardiovascular death and HF hospitalization limit the use of febuxostat and pegloticase as ULT in this population. Ultimately, the selection of agents used for acute gout management and long-term ULT should be individualized according to patient and agent cardiovascular risk factors.

Association of gout with major adverse cardiovascular events and all-cause mortality in patients with peripheral artery disease

BACKGROUND AND AIMS

Prior epidemiological studies have suggested that individuals with gout are at greater risk of cardiovascular events, but there have been no studies in people with peripheral artery disease (PAD). The aim of this study was to investigate the relationship between gout and major adverse cardiovascular events (MACE) and all-cause mortality in people with PAD.

METHODS

Participants with a range of PAD presentations, including carotid artery disease, aortic or peripheral aneurysm and lower limb PAD, were prospectively recruited from outpatient vascular departments within Australia. MACE (myocardial infarction, stroke or cardiovascular death) and all-cause mortality were identified through out-patient follow-up and linked medical records. Propensity-score matching was undertaken to generate a matched cohort of patients with and without a history of gout. Kaplan-Meier survival analysis and Cox-proportional hazard analysis were used to examine the association of gout with MACE and all-cause mortality.

RESULTS

A total of 4308 people with PAD, of whom 334 had a history of gout, were included and followed for a median (inter-quartile range) of 2.1 (0.1-5.9) years. In the unadjusted analyses, participants with gout were at increased risk of MACE (hazard ratio, HR 1.37, 95% confidence intervals, CI 1.09-1.71, p = 0.006) and all-cause mortality (HR 1.38, 95% 1.13-1.68, p = 0.002), however, the associations were lost in the adjusted analyses. In the propensity-score matched cohort, gout was not significantly associated with an increased risk for MACE or all-cause mortality.

CONCLUSIONS

Gout was not independently associated with increased cardiovascular events in PAD patients.

Comparative cardiovascular risk of allopurinol versus febuxostat in patients with gout: a nation-wide cohort study

OBJECTIVE

To compare cardiovascular (CV) risk among gout patients initiating allopurinol vs febuxostat.

METHODS

Using 2002-2015 Korean National Health Insurance Service data for the entire Korean population, we conducted a cohort study on gout patients initiating allopurinol or febuxostat. The primary outcome was a composite CV end point of myocardial infarction, stroke/transient ischaemic attack, or coronary revascularization. Secondary outcomes were individual components of the primary outcome, and all-cause mortality. We used propensity score-matching with a 4:1 ratio for allopurinol and febuxostat initiators to control for confounding. Competing risk analyses were done for non-fatal outcomes accounting for deaths.

RESULTS

We included 39 640 allopurinol initiators propensity score-matched on 9910 febuxostat initiators. The mean age was 59.1 years and 78.4% were male. The incidence rate per 100 person-years for the primary outcome was 1.89 for allopurinol and 1.84 for febuxostat initiators. The corresponding hazard ratio comparing allopurinol vs febuxostat initiators was 1.09 (95% CI: 0.90, 1.32). No significant difference was found for the secondary outcomes, including all-cause mortality (hazard ratio 0.96; 95% CI: 0.79, 1.16). Subgroup analyses limited to those at high CV risk and to equipotent-dose initiators (i.e. allopurinol ⩾300 mg/day vs febuxostat ⩾40 mg/day) showed similar results.

CONCLUSION

Overall, this large Korean population-based study suggests no difference in the risk of non-fatal CV events and all-cause mortality between allopurinol and febuxostat initiators. These findings are consistent with the recent US Medicare population study, although the current study population consisted of younger Asians.

2017 ACC/AHA blood pressure classification and incident peripheral artery disease: The Atherosclerosis Risk in Communities (ARIC) Study

AIMS

The aim of this study was to evaluate the associations of blood pressure categorization based on the 2017 American College of Cardiology and American Heart Association guideline with the risk of peripheral artery disease (PAD).

METHODS

Among 13,113 middle-aged participants, we investigated the associations of 2017 blood pressure categories (systolic <120 and diastolic <80 mmHg (normal if no anti-hypertensive medications; reference), 120-129 and <80 (elevated), 130-139 and/or 80-89 (stage 1 hypertension), and ≥140 and/or ≥90 (stage 2 hypertension)) with incident PAD (hospitalizations with a diagnosis or leg revascularization) using Cox regression models. Analyses were separately conducted in individuals with and without anti-hypertensive medications.

RESULTS

During a median follow-up of 25.4 years, 466 incident PAD occurred (271 cases in 9858 participants without anti-hypertensive medications). In participants without anti-hypertensive medications, we observed significant hazard ratios of PAD in elevated blood pressure (1.80 (1.28-2.51)) and stage 2 hypertension (2.40 (1.72-3.34)), but not in stage 1 hypertension. Analyzing systolic and diastolic blood pressure separately, higher systolic blood pressure categories showed significant associations with incident PAD in a graded fashion whereas, for diastolic blood pressure, only ≥90 mmHg did. Generally similar patterns were seen among participants on anti-hypertensive medication, while they had higher risk of PAD than those without at each blood pressure category.

CONCLUSIONS

Systolic blood pressure, including the category of 130-139 mmHg, showed stronger associations with incident PAD than did diastolic blood pressure. Consequently, elevated blood pressure conferred similar or even greater risk of PAD than stage 1 hypertension, with implications on how to interpret new blood pressure categories in terms of leg vascular health.

Uric acid within the "normal" range predict 9-year cardiovascular mortality in older individuals. The InCHIANTI study

BACKGROUND AND AIMS

Increased uric acid levels correlate with cardiovascular disease and cardiovascular/overall mortality. To identify a uric acid threshold above which cardiovascular mortality rises, we studied the relationship between uric acid concentration and overall/cardiovascular mortality.

METHODS AND RESULTS

We analyzed data from the InCHIANTI study, a cohort study of Italian community-dwelling people with 9 years of follow-up. We selected a sample of 947 individuals over 64 years of age, free from cardio-cerebrovascular disease and with available uric acid measurement at baseline. The sample was divided according to plasma uric acid tertiles. The Hazard ratio (HR) for mortality was calculated by multivariate Cox proportional hazard model. Mean age of participants was 75.3 ± 7.3 years; the mean value of uric acid was 5.1 ± 1.4 mg/dl. Over 9-years of follow-up, 342 (36.1%) participants died, 143 deaths (15.1%) were due to cardiovascular disease. Subjects with higher uric acid concentrations presented a higher cardiovascular mortality [II (4.6-5.5 mg/dl) vs I (1.8-4.5 mg/dl) tertile HR: 1.98, 95%C.I. 1.22-3.23; III (≥5.6 mg/dl) vs I tertile HR: 1.87, 95%C.I. 1.13-3.09]. We found a non-linear association between uric acid concentrations and cardiovascular mortality with the lowest mortality for values of about 4.1 mg/dl and a significant risk increment for values above 4.3 mg/dl.

CONCLUSION

In community-dwelling older individuals free from cardio-cerebrovascular events, the lowest 9-year cardiovascular mortality was observed for uric acid values far below current target values. If confirmed, these data might represent the background for investigating the efficacy of uric acid levels reduction in similar populations.

The Effects of Ginsenosides and Anserine on the Up-Regulation of Renal Aquaporins 1–4 in Hyperuricemic Mice

Hyperuricemia is a metabolic disease of the kidney that results in decreased uric acid excretion. Here, we aimed to investigate the effects of ginsenosides and anserine on hyperuricemia and the expression of aquaporin (AQP) 1–4, which are indicators of renal excretion. Ginsenosides and anserine were administered separately or together after the establishment of hyperuricemia with adenine in BALB/c mice. Renal function indexes such as serum uric acid, creatinine, and urea nitrogen were measured in each group of mice, and the expression of AQP1–4 in renal tissues was detected. Serum uric acid and urea nitrogen were decreased in the ginsenoside and the anserine +UA groups. Meanwhile, the uric acid excretion and clearance rate were clearly increased in the co-treatment +UA group ([Formula: see text].05). Moreover, ginsenosides or anserine ginsenosides or anserine alone and treatment with both increased the expression of AQP1–4; however, the synergistic effects were more significantly enhanced ([Formula: see text].01). We provide the first reported evidence that ginsenosides and anserine have synergistic effects on uric acid excretion. The improvement in renal function in hyperuricemic mice after treatment with ginsenosides and anserine may result from up-regulation of AQP1–4 expressions.

Association of Blood Pressure Measurements With Peripheral Artery Disease Events

BACKGROUND

Current guidelines recommend treating hypertension in patients with peripheral artery disease (PAD) to reduce the risk of cardiac events and stroke, but the effect of reducing blood pressure on lower extremity PAD events is largely unknown. We investigated the association of blood pressure with lower extremity PAD events using data from the ALLHAT trial (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

METHODS

ALLHAT investigated the effect of different antihypertensive medication classes (chlorthalidone, amlodipine, lisinopril, or doxazosin) on cardiovascular events. With the use of these data, the primary outcome in our analysis was time to first lower extremity PAD event, defined as PAD-related hospitalization, procedures, medical treatment, or PAD-related death. Given the availability of longitudinal standardized blood pressure measurements, we analyzed systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure as time-varying categorical variables (reference categories 120-129 mm Hg for SBP, 70-79 mm Hg for DBP, and 45-54 mm Hg for pulse pressure) in separate models. We used extended Cox regression with death as a competing risk to calculate the association of each blood pressure component with PAD events, and report the results as subdistribution hazard ratios and 95% CIs.

RESULTS

The present analysis included 33 357 patients with an average age of 67.4 years, 53.1% men, 59.7% white race, and 36.2% with diabetes mellitus. The median baseline blood pressure was 146/84 mm Hg. Participants were followed for a median of 4.3 (interquartile range, 3.6-5.3) years, during which time 1489 (4.5%) had a lower extremity PAD event, and 4148 (12.4%) died. In models adjusted for demographic and clinical characteristics, SBP <120 mm Hg was associated with a 26% (CI, 5%-52%; P=0.015) higher hazard and SBP≥160 mm Hg was associated with a 21% (CI, 0%-48%; P=0.050) higher hazard for a PAD event, in comparison with SBP 120 to 129 mm Hg. In contrast, lower, but not higher, DBP was associated with a higher hazard of PAD events: for DBP <60 mm Hg (hazard ratio, 1.72; CI, 1.38-2.16). Pulse pressure had a U-shaped association with PAD events.

CONCLUSIONS

In this reanalysis of data from ALLHAT, we found a higher rate of lower extremity PAD events with higher and lower SBP and pulse pressure and with lower DBP. Given the recent revised blood pressure guidelines advocating lower SBP targets for overall cardiovascular risk reduction, further refinement of optimal blood pressure targets specific to PAD is needed.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT00000542.

Comorbidity in gout at the time of first diagnosis: sex differences that may have implications for dosing of urate lowering therapy

Background

The aim of this study is to examine the occurrence of comorbidities at the time of first diagnosis of gout compared with matched population controls, overall and by sex, as well as to examine the crude and age-standardized prevalence of these comorbidities in men and women with gout at first diagnosis.

Methods

A population-based study used data from Swedish national and regional registers, including 14,113 gout patients aged ≥ 20 years, with a first recorded diagnosis of gout between 1 January 2006 and 31 December 2012, and 65,782 population controls, matched by age, sex and county. Prevalence ratios (95% confidence intervals) comparing gout cases and controls were calculated, overall and by sex. Crude and age-standardized prevalence (95% confidence interval) of all comorbidities in gout patients were calculated, to show differences between sexes, taking also the higher age at diagnosis in women into account.

Results

All examined comorbidities were 1.2–2.5-fold more common in gout patients at diagnosis than in population controls in both sexes. Women with gout were on average 6 years older than men at first gout diagnosis and most comorbidities, including obesity and diuretic use, were or tended to be more frequent in women than in men. When standardizing for age, women had a higher prevalence of thromboembolism (6.6% vs 5.2%) and chronic obstructive pulmonary disease (3.1% vs 2.4%). Men, on the other hand, had a higher prevalence of coronary heart disease (9.4% vs 6.4%), atrial fibrillation (9.0% vs 6.0%), congestive heart failure (7.7% vs 6.6%) and stroke (4.1% vs 3.3%).

Conclusions

The occurrence of most comorbidities was significantly increased at first diagnosis of gout in both sexes. Women were older at diagnosis and had higher occurrence of most comorbidities, including obesity and diuretic use, factors that increase serum urate, and this needs to be taken into account when starting and optimizing urate lowering therapy. These sex differences were attenuated when standardizing for age and the occurrence of cardiovascular diseases was actually higher in men.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1596-x) contains supplementary material, which is available to authorized users.

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.

An association of smoking with serum urate and gout: A health paradox

BACKGROUND

The potential effect of cigarette smoking on levels of serum urate and risk of gout has been considered by a large number of studies, either as the primary variable of interest or as a covariate.

METHODS

Here we systematically review the published evidence relating to the relationship of smoking with serum urate, hyperuricaemia, and gout.

RESULTS

Many studies have reported that smoking reduces serum urate, however, the evidence has not been conclusive with other studies pointing to the opposite or no effect. It has also been suggested that smoking reduces the risk of gout, although there is some evidence to contradict this finding.

CONCLUSION

A consensus has yet to be reached as to the effect of smoking on serum urate levels and the risk of gout.

Asymptomatic hyperuricemia and coronary artery disease in elderly patients without comorbidities

Because many subjects with hyperuricemia have comorbidities, it can be difficult to differentiate the role of hyperuricemia from that of other comorbidities of coronary artery disease (CAD). Subjects aged ≥ 65 years were enrolled in the study and were available at enrollment and at 5-year follow-up. Subjects were excluded if they were overweight or obese, hypertensive, diabetic, hyperlipidemic, had a pre-existing cardiovascular disease, a history of gout or hyperuricemia on medications, or chronic kidney disease as estimated by a glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m². We used Poisson regression to estimate the hazard ratio (HR) for incident CAD events between hyperuricemic (> 7 mg/dL in men and ≥ 6 mg/dL in women) and normouricemic subjects. A total of 2,142 subjects without comorbidities (mean age of 70.7 ± 5.9 years, 1,194 men) were followed for 57.4 ± 8.9 months. Hyperuricemia was associated with an increased cumulative incidence of incident CAD events (15.0% versus 8.8%, P < 0.001). After adjusting for confounding factors, hyperuricemia independently predicted the risk of incident CAD events (HR=1.71, 95% CI 1.26-2.34). In conclusion, asymptomatic hyperuricemia is a valuable biomarker for predicting the development of incident CAD events.

Association of Serum Uric Acid Levels with Leg Ischemia in Patients with Peripheral Arterial Disease after Treatment

Aim: We investigated the relationships of serum uric acid levels with the progression of atherosclerosis in patients with peripheral arterial disease (PAD) after treatment.

Methods: Subjects were male patients diagnosed with PAD. Atherosclerosis at the common carotid artery was evaluated based on its intima-media thickness (IMT). Leg arterial flow was evaluated by measuring ankle-brachial index (ABI) and exercise-induced decrease in ABI.

Results: Among various risk factors including age, blood pressure, adiposity, estimated glomerular filtration rate, and blood lipid, blood glucose, uric acid, fibrinogen and C-reactive protein levels, only uric acid levels showed significant correlations with ABI [Pearson's correlation coefficient, −0.292 (p < 0.01)] and leg exercise-induced decrease in ABI [Pearson's correlation coefficient, 0.236 (p < 0.05)]. However, there was no significant correlation between uric acid levels and maximum or mean IMT. Odds ratios of subjects with the 3rd tertile versus subjects with the 1st tertile for uric acid levels were significantly higher than the reference level of 1.00 for low ABI [4.44 (95% confidence interval, 1.45–13.65, p < 0.01)] and for high % decrease in ABI after exercise [4.31 (95% confidence interval, 1.34–13.82, p < 0.05)]. The associations of uric acid levels with the indicators of leg ischemia were also found after adjustment for age, history of revascularization therapy, diabetes, smoking, alcohol consumption, body mass index, triglyceride levels, and renal function.

Conclusion: Uric acid levels are associated with the degree of leg ischemia in patients with PAD. Further interventional studies are needed to determine whether the correction of uric acid levels is effective in preventing the progression of PAD.

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.

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.

Usual blood pressure, peripheral arterial disease, and vascular risk: cohort study of 4.2 million adults

OBJECTIVES

To determine the subgroup specific associations between usual blood pressure and risk of peripheral arterial disease, and to examine the relation between peripheral arterial disease and a range of other types of vascular disease in a large contemporary cohort.

DESIGN

Cohort study.

SETTING

Linked electronic health records from 1990 to 2013 in the United Kingdom.

PARTICIPANTS

4,222,459 people aged 30-90 years, registered at a primary care practice for at least one year and with a blood pressure measurement.

MAIN OUTCOME MEASURES

Time to first diagnosis of new onset peripheral arterial disease and time to first diagnosis of 12 different vascular events.

RESULTS

A 20 mm Hg higher than usual systolic blood pressure was associated with a 63% higher risk of peripheral arterial disease (hazard ratio 1.63, 95% confidence interval 1.59 to 1.66). The strength of the association declined with increasing age and body mass index (P<0.001 for interaction) but was not modified by sex or smoking status. Peripheral arterial disease was associated with an increased risk of 11 different vascular events, including ischaemic heart disease (1.68, 1.58 to 1.79), heart failure (1.63, 1.52 to 1.75), aortic aneurysm (2.10, 1.79 to 2.45), and chronic kidney disease (1.31, 1.25 to 1.38), but not haemorrhagic stroke. The most common initial vascular event among those with peripheral arterial disease was chronic kidney disease (24.4% of initial events), followed by ischaemic heart disease (18.5% of initial events), heart failure (14.7%), and atrial fibrillation (13.2%). Overall estimates from this cohort were consistent with those derived from traditional studies when we pooled the findings in two meta-analyses.

CONCLUSIONS

Raised blood pressure is a strong risk factor for peripheral arterial disease in a range of patient subgroups. Furthermore, clinicians should be aware that those with established peripheral arterial disease are at an increased risk of a range of other vascular events, including chronic kidney disease, ischaemic heart disease, heart failure, atrial fibrillation, and stroke.

Characteristics of the first metatarsophalangeal joint in gout and asymptomatic hyperuricaemia: a cross-sectional observational study

Background

This study aimed to identify patient-reported outcomes and clinician-assessed characteristics of the first metatarsophalangeal joint (1MTPJ) in people with gout and with asymptomatic hyperuricaemia by comparing them to normouricaemic controls.

Methods

Twenty four people with gout (without current symptoms of acute arthritis), 29 with asymptomatic hyperuricaemia and 34 age- and sex-matched controls participated in this cross-sectional observational study. Patient-reported outcomes included 1MTPJ pain, foot pain and disability, body pain, lower limb function, activity limitation and overall wellbeing. Clinician-assessed characteristics of the 1MTPJ included range of motion (ROM), plantar- and dorsi-flexion force, foot posture, temperature and hallux valgus severity.

Results

Compared to controls, participants with gout reported greater 1MTPJ pain (p = 0.014), greater foot pain and disability (p < 0.001), increased odds of having disabling foot pain (odds ratio (OR) 13.4, p < 0.001), decreased lower limb function for daily living (p = 0.002) and recreational (p < 0.001) activities, increased activity limitation (p = 0.002), reduced overall wellbeing (p = 0.034), reduced ROM (p < 0.001), reduced plantarflexion force (p = 0.012), increased 1MTPJ plantar (p = 0.004), dorsal (p = 0.003) and medial (p = 0.004) temperature and had increased odds of having more severe hallux valgus (OR 0.3 p = 0.041). Compared to controls, participants with asymptomatic hyperuricaemia had increased odds of having disabling foot pain (OR 4.2, p = 0.013), increased activity limitation (p = 0.033), decreased lower limb function for daily living (p = 0.026) and recreational (p = 0.010) activities, increased 1MTPJ plantarflexion force (p = 0.004) and a more pronated foot type (p = 0.036).

Conclusions

People with gout demonstrate 1MTPJ-specific changes indicative of subclinical inflammation, even in the absence of acute arthritis. People with asymptomatic hyperuricaemia, who exhibit no features or symptoms of gout, also report high levels of foot- and lower limb-related pain and disability.

Aging, not menopause, is associated with higher prevalence of hyperuricemia among older women

OBJECTIVE

This work aims to study the associations, if any, of hyperuricemia, gout, and menopause status in the US population.

METHODS

Using multiyear data from the National Health and Nutrition Examination Survey, we performed unmatched comparisons and one to three age-matched comparisons of women aged 20 to 70 years with and without hyperuricemia (serum urate ≥6 mg/dL). Analyses were performed using survey-weighted multiple logistic regression and conditional logistic regression, respectively.

RESULTS

Overall, there were 1,477 women with hyperuricemia. Age and serum urate were significantly correlated. In unmatched analyses (n = 9,573 controls), postmenopausal women were older, were heavier, and had higher prevalence of renal impairment, hypertension, diabetes, and hyperlipidemia. In multivariable regression, after accounting for age, body mass index, glomerular filtration rate, and diuretic use, menopause was associated with hyperuricemia (odds ratio, 1.36; 95% CI, 1.05-1.76; P = 0.002). In corresponding multivariable regression using age-matched data (n = 4,431 controls), the odds ratio for menopause was 0.94 (95% CI, 0.83-1.06). Current use of hormone therapy was not associated with prevalent hyperuricemia in both unmatched and matched analyses.

CONCLUSIONS

Age is a better statistical explanation for the higher prevalence of hyperuricemia among older women than menopause status.

Australian and New Zealand recommendations for the diagnosis and management of gout: integrating systematic literature review and expert opinion in the 3e Initiative

AIM

To develop evidence-based recommendations for the diagnosis and management of gout in Australia and New Zealand as part of the multi-national 3e Initiative.

METHOD

Using a formal voting process, a panel of 78 international rheumatologists selected 10 key clinical questions pertinent to the diagnosis and management of gout. An additional question was also developed by participating Australian and New Zealand rheumatologists. Each question was investigated with a systematic literature review. MEDLINE, EMBASE, Cochrane CENTRAL and abstracts from 2010 to 2011 European League Against Rheumatism and American College of Rheumatology meetings were searched in each review. Relevant studies were independently reviewed by two individuals for data extraction and synthesis and risk of bias assessment. Using this evidence, 47 Australian and New Zealand rheumatologists developed national recommendations. For each recommendation the level of agreement was assessed and the level of evidence graded.

RESULT

Eleven recommendations were produced relating to the diagnosis of gout, different aspects of the management of gout, cardiovascular and renal comorbidities and the management of asymptomatic hyperuricemia. The mean level of agreement with the recommendations was 9.1 on a 1-10 scale, with 10 representing full agreement.

CONCLUSION

Eleven Australian and New Zealand recommendations on the diagnosis and management of gout were developed combining systematically reviewed evidence with local expertise, enhancing their utility in clinical practice.

Serum Uric Acid, Gender, and Low Ankle Brachial Index in Adults With High Cardiovascular Risk

Uric acid (UA) has been reported to be associated with cardiovascular disease (CVD) in caucasians. However, it is unclear whether this association remains significant in a Chinese population. The present study aimed to investigate the association between UA and low ankle brachial index (ABI), a measurement of peripheral arterial disease, in Chinese patients. A total of 6262 hospital-based patients with high CVD risk were enrolled. Low ABI was defined as ABI ≤0.9 in either side. Low ABI was detected in 1390 (22.2%) patients. Higher UA was significantly associated with higher risk of low ABI and modified by gender (P = .0045). After adjusting for age, body mass index, total cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein, fasting glucose, hypertension, and smoking, participants in the highest quartile of UA exhibited 37% (odds ratio [OR]:1.37, 95% confidence interval [CI]: 1.03-1.82) higher risk of low ABI compared to those in the lowest quartile in men, while OR (95% CI) was 1.69 (1.29-2.22) for women. However, when kidney function was further adjusted, the associations were attenuated in both men and women and were significant only in women. The results were suggestive of higher UA associating with higher risk of low ABI in women, and the association was largely driven by kidney function, especially in men.

Increased risk of vascular disease associated with gout: a retrospective, matched cohort study in the UK clinical practice research datalink

Objectives

To determine whether gout increases risk of incident coronary heart disease (CHD), cerebrovascular (CVD) and peripheral vascular disease (PVD) in a large cohort of primary care patients with gout, since there have been no such large studies in primary care.

Methods

A retrospective cohort study was performed using data from the Clinical Practice Research Datalink (CPRD). Risk of incident CHD, CVD and PVD was compared in 8386 patients with an incident diagnosis of gout, and 39 766 age, sex and registered general practice-matched controls, all aged over 50 years and with no prior vascular history, in the 10 years following incidence of gout, or matched index date (baseline). Multivariable Cox Regression was used to estimate HRs and covariates included sex and baseline measures of age, Body Mass Index, smoking, alcohol consumption, Charlson comorbidity index, history of hypertension, hyperlipidaemia, chronic kidney disease, statin use and aspirin use.

Results

Multivariable analysis showed men were at increased risk of any vascular event (HRs (95% CIs)) HR 1.06 (1.01 to 1.12), any CHD HR 1.08 (1.01 to 1.15) and PVD HR 1.18 (1.01 to 1.38), while women were at increased risk of any vascular event, HR 1.25 (1.15 to 1.35), any CHD HR 1.25 (1.12 to 1.39), and PVD 1.89 (1.50 to 2.38)) but not any CVD.

Conclusions

In this cohort of over 50s with gout, female patients with gout were at greatest risk of incident vascular events, even after adjustment for vascular risk factors, despite a higher prevalence of both gout and vascular disease in men. Further research is required to establish the reason for this sex difference.

Improving cardiovascular and renal outcomes in gout: what should we target?

Epidemiological and experimental studies have shown that hyperuricaemia and gout are intricately linked with hypertension, metabolic syndrome, chronic kidney disease and cardiovascular disease. A number of studies suggest that hyperuricaemia and gout are independent risk factors for the development of these conditions and that these conditions account, in part, for the increased mortality rate of patients with gout. In this Review, we first discuss the links between hyperuricaemia, gout and these comorbidities, and present the mechanisms by which uric acid production and gout might favour the development of cardiovascular and renal diseases. We then emphasize the potential benefit of urate-lowering therapies on cardiovascular and renal outcomes in patients with hyperuricaemia. The mechanisms that link elevated serum uric acid levels and gout with these comorbidities seem to be multifactorial, implicating low-grade systemic inflammation and xanthine oxidase (XO) activity, as well as the deleterious effects of hyperuricaemia itself. Patients with asymptomatic hyperuricaemia should be treated by nonpharmacological means to lower their SUA levels. In patients with gout, long-term pharmacological inhibition of XO is a treatment strategy that might also reduce cardiovascular and renal comorbidities, because of its dual effect of lowering SUA levels as well as reducing free-radical production during uric acid formation.

Hyperuricemia and incident cardiovascular disease and noncardiac vascular events in patients with rheumatoid arthritis

Objective. To evaluate whether hyperuricemia is a risk factor for cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA). Methods. A population-based inception cohort of patients diagnosed between 1980 and 2007 with adult-onset RA was assembled. A comparison cohort of age- and sex-matched subjects without RA (non-RA) was also assembled. All clinically obtained uric acid values were collected. CVD and noncardiac vascular events were recorded for each patient. Cox proportional hazards models were used to assess the impact of hyperuricemia on development of CVD, mortality, and noncardiac vascular disease. Results. In patients without RA, hyperuricemia was associated with heart failure (HR: 1.95; 95% CI: 1.13–3.39) and CVD (HR: 1.59; 95% CI: 0.99–2.55). In patients with RA, hyperuricemia was not significantly associated with CVD but was significantly associated with peripheral arterial events (HR: 2.52; 95% CI: 1.17–5.42). Hyperuricemia appeared to be more strongly associated with mortality among RA patients (HR: 1.96; 95% CI: 1.45–2.65) than among the non-RA subjects (HR: 1.57; 95% CI: 1.09–2.24). Conclusion. In patients with RA, hyperuricemia was a significant predictor of peripheral arterial events and mortality but not of CVD.

Interaction of inflammation, hyperuricemia, and the prevalence of hypertension among adults free of metabolic syndrome: NHANES 2009-2010

Background

Hyperuricemia and markers of inflammation are correlated with the risk for hypertension. Whether hyperuricemia has any impact on the association between C‐reactive protein (CRP) and hypertension is not known.

Methods and Results

We analyzed cross‐sectional data from the National Health and Nutrition Examination Survey, 2009–2010, using ordinary least squares and logistic regression models. Those who met the criteria for metabolic syndrome, had self‐reported gout, or were <20 years old were excluded. For each 1‐SD increase in serum urate, the serum CRP concentration was 20% higher in unadjusted linear regression models and 13% higher in multivariable linear regression models, after accounting for the effects of age, sex, race, socioeconomic and educational strata, renal function, lipids, smoking, and body mass index. In multivariable models adjusting for the same covariates, hyperuricemia was associated with hypertension with an odds ratio of 2.21 (1.71 to 2.85). When analyzed separately, this was observed in men and women. In multivariable analyses of the overall sample, elevated CRP levels were not associated with hypertension.

Conclusions

Among adults free of metabolic syndrome, elevated uric acid, but not elevated CRP, is independently associated with prevalent hypertension.

Treatment of Asymptomatic Hyperuricemia and Prevention of Vascular Disease: A Decision Analytic Approach

Objective.

Elevated serum urate may be associated with an increase in cardiovascular (CV) disease. Treating asymptomatic hyperuricemia with urate-lowering drugs such as allopurinol may reduce CV events. We designed a model to simulate the effect of allopurinol treatment on reducing frequency of CV events in individuals with elevated serum urate.

Methods.

A Markov state-transition model was constructed to assess occurrence of vascular events (VE) for 2 treatment strategies: treat all asymptomatic individuals with allopurinol (Treat All) and treat only if symptomatic (Treat Symptomatic). The model simulated a hypothetical cohort of 50-year-old men with different serum urate concentrations (6–6.9 and 7–7.9 mg/dl) followed over 20 years. Age and sex subgroups were analyzed. Model inputs were derived from current literature. The main outcome measures were mean number of VE and mean number of deaths from VE.

Results.

For 50-year-old men with serum urate 6.0–6.9 mg/dl, individuals in the Treat All strategy have a 30% reduction in the mean number of VE compared to those in the Treat Symptomatic strategy (mean VE: 0.078 vs 0.11), and a 39% reduction in mean number of deaths from VE. At higher serum urate concentrations, treatment is more effective in reducing the mean number of VE and mean number of deaths from VE (38% event, 54% death). Results for women show similar trends. As the cohort ages, treatment has less effect on reducing VE. The number needed to treat to prevent 1 event is 20 (men, 7.0–7.9 mg/dl).

Conclusion.

The model predicts that treating asymptomatic hyperuricemia with allopurinol is most effective in preventing VE at a serum urate above 7.0 mg/dl in men and 5.0 mg/dl in women.

Comorbidities in patients with crystal diseases and hyperuricemia

Crystal arthropathies are among the most common causes of painful inflammatory arthritis. Gout, the most common example, has been associated with cardiovascular and renal disease. In recent years, evidence for these associations and those involving other comorbidities, such as the metabolic syndrome, have emerged, and the importance of asymptomatic hyperuricemia has been established. In this review, an update on evidence, both experimental and clinical, is presented, and associations between hyperuricemia, gout, and several comorbidities are described. Causality regarding calcium pyrophosphate arthropathy and associated comorbidities is also reviewed.

Impact of allopurinol on risk of myocardial infarction

BACKGROUND

Gout therapy includes xanthine oxidase inhibitors (XOI) and colchicine, which have both been associated with decreased cardiovascular risk. However, their effects on major cardiac events, such as myocardial infarction (MI), need to be investigated further.

OBJECTIVES

To investigate whether XOIs and colchicine are associated with decreased risk of MI.

METHODS

This case-control study compared patients with first-ever MI and matched controls. Cases were recruited from the Pharmacoepidemiological General Research on MI registry. Controls were selected from a referent population (n=8444) from general practice settings.

RESULTS

The study sample consisted of 2277 MI patients and 4849 matched controls. Use of allopurinol was reported by 3.1% of cases and 3.8 of controls, and 1.1% of cases and controls used colchicine. The adjusted OR (95% CI) for MI with allopurinol use was 0.80 (0.59 to 1.09). When using less stringent matching criteria that allowed for inclusion of 2593 cases and 5185 controls, the adjusted OR was 0.73 (0.54 to 0.99). Similar results were found on analysis by sex and hypertension status. Colchicine used was not associated with a decreased risk of MI (aOR=1.17 (0.70 to 1.93)).

CONCLUSIONS

Allopurinol may be associated with a reduced risk of MI. No decreased risk of MI was found in colchicine users. Besides its urate-lowering property, allopurinol might have a cardioprotective effect.

Xanthine oxido-reductase, free radicals and cardiovascular disease. A critical review

Free radical mediated pathologies occupy a special place in medical semiology and in mechanistic interpretation of diseases. Free radicals, or better reactive oxygen species (ROS) or reactive nitrogen species (RNS) play also an important role in cell signaling. This is the basis of the ambivalent (Jekyll-Hyde) situation of ROS in biology and pathology. Aging itself is attributed by a popular theory to free radicals. A number of ROS-scavenging substances and procedures were described without however reaching credibility for their therapeutic value. An interesting exception is the xanthine oxido-reductase produced ROS and their role in cardiovascular disease. Allopurinol inhibition of xanthine oxido-reductase was shown to be efficient in some cases of cardiovascular diseases. Another important aspect of xanthine oxido-reductase produced ROS is their antibacterial capacity considered to be of importance with newborns fed on milk rich in this enzyme as well as at the gastrointestinal barrier. This ambivalent role of xanthine oxido-reductase justifies this review on the basic enzymatic mechanisms involved, derived ROS production, their role in the above mentioned biological processes and especially the interest of the inhibition of this enzyme as a preventive or curative measure in some cardiovascular pathologies.

Changes in serum uric acid levels and cardiovascular events: a meta-analysis

BACKGROUND AND AIMS

The association between serum uric acid (SUA) levels and cardiovascular (CV) risk or all-cause death has been repeatedly reported. However, it has not been assessed whether reduction of SUA levels is associated with reduced CV risk. The aim of the current study was to evaluate the relationship between changes of SUA levels and CV events as well as all-cause death.

METHODS AND RESULTS

Randomised trials reporting SUA at baseline and at the end of follow-up and clinical end-points (all-cause death, myocardial infarction (MI), stroke, heart failure (HF) and CV death) were included in the study. Meta-regression analysis was performed to test the relationship between SUA changes and clinical end-points. Eleven trials enrolling 21,373 participants followed up for 2.02 ± 1.76 years and reporting 4533 events were included. In meta-regression analysis, no relationship between SUA changes from baseline to end of follow-up and the composite outcome including CV death, stroke, MI and HF was found (change in Tau(2) (t) = -0.64; p Tau (p) = 0.541). Similarly, no relationship was found between SUA changes and single components of the composite outcome (MI: t = -0.83; p = 0.493; stroke: t = 0.46; p = 0.667; HF: t = 2.44; p = 0.162; CV death: t = -0.54; p = 0.614) and all-cause death (t = -0.72; p = 0.496). Results were confirmed by sensitivity analysis. No heterogeneity among studies or publication bias was detected.

CONCLUSIONS

Changes in SUA levels observed during pharmacologic treatments do not predict the risk of all-cause death or CV events. As SUA levels are associated with increased CV risk, additional studies with direct xanthine-oxidase inhibitors are requested.

The effect of gout on health-related quality of life, work productivity, resource use and clinical outcomes among patients with hypertension

Although gout has been found to be associated with health-related quality of life (HRQoL), few studies have examined the burden of gout in the presence of concomitant cardiometabolic conditions. The present study evaluated the effect of gout on HRQoL and work productivity among patients with hypertension. Data from the 2010 National Health and Wellness Survey were obtained for respondents ≥18 years of age who had self-reported, physician-diagnosed hypertension or blood pressure levels ≥140/90 mmHg (≥130/80 mmHg for those with physician-diagnosed diabetes or chronic kidney disease). Bivariate analysis was used to evaluate differences between patients with and without self-reported comorbid gout. Generalized linear models were used to evaluate differences in productivity (using the Work Productivity and Activity Impairment scale) and HRQoL (using the physical component summary [PCS], mental component summary and health utilities from the SF-12v2 health survey). As uric acid levels may influence other organ systems, core modeling did not include comorbidities other than osteoarthritis and depression as covariates. Sensitivity analyses were controlled for the Charlson comorbidity index. A total of 22,686 patients with self-reported hypertension met study eligibility requirements. Of these, 4.51% reported having gout. These patients were older, more likely to be male and have insurance through Veteran Affairs (all p-values < 0.05). Patients with comorbid gout reported lower levels of mental component summary scores (47.25 vs 48.93), PCS scores (39.06 vs 43.78) and health utilities (0.68 vs 0.73; all p-values < 0.05). For both PCS and health utilities, differences between groups exceeded clinically meaningful cutoffs. Sensitivity analyses conducted on PCS and health utilities uncovered slightly smaller, but statistically significant and clinically meaningful, effects (p-values < 0.05). The effect of gout on overall work impairment (23.33 vs 17.40% with and without comorbid gout, respectively) remained after controlling for the Charlson comorbidity index. Significantly greater impairment in daily activities (38.96 vs 28.32%; p < 0.05) was also observed among patients with comorbid gout. Results demonstrate that gout has significant and clinically meaningful impact on work productivity, physical HRQoL and utilities independent of other health conditions.

Tophaceous gout and high level of hyperuricaemia are both associated with increased risk of mortality in patients with gout

BACKGROUND

While several studies have reported a link between the presence of gout and adverse cardiovascular (CV) events in the general population, none has addressed the question of whether the mortality risk of patients with gout is influenced by disease severity.

METHODS

We applied survival analysis methodology to prospectively collected data on clinical and radiographic measures of disease severity and mortality in a specialty clinic based cohort of 706 patients with gout (1992-2008). Standardised mortality ratios (SMR) were calculated to assess the magnitude of excess mortality among patients with gout compared with the underlying general population.

RESULTS

Mean follow-up was 47 months. Tophaceous deposition was present in 30.5% of patients; >4 joints were involved in 34.6% of cases. Mean annual flare rate was 3.4. Arterial hypertension (41.2%), hyperlipidaemia (42.2%), diabetes mellitus (20.1%), renal function impairment (26.6%) and a previous CV event (25.3%) were recorded. 64 (9.1%) patients died, death being attributed to vascular causes in 38 (59%) patients. SMR for gout patients was 2.37 (95% CI 1.82 to 3.03), 1.57 (1.18 to 2.05) and 4.50 (2.06 to 8.54) overall, and in men and women, respectively. The presence of tophi and the highest baseline serum urate (SU) levels were independently associated with a higher risk of mortality, in addition to age, loop diuretic use and a history of a previous vascular event. In the multivariable survival regression models, with time varying covariates, the presence of tophi remained a significant mortality risk after adjustment for baseline SU levels (1.98; 1.24 to 3.20).

CONCLUSIONS

High baseline SU level and the presence of subcutaneous tophi were both associated with an increased risk of mortality in patients with gout, in most cases attributed to a CV cause. This suggests a plausible pathophysiological link between greater total body urate load and CV disease.

Monocyte chemoattractant protein 1 is correlated with glycemic control and peripheral arterial disease in type 2 diabetic patients with metabolic syndrome

We evaluated the serum levels of monocyte chemoattractant protein 1 (MCP-1) and their association with peripheral arterial disease (PAD) in 199 patients with type 2 diabetes mellitus (T2DM) and metabolic syndrome ([MetS], group A) in comparison with 109 healthy controls (group B). In group A, MCP-1 levels were significantly (P < .001) higher than group B and exhibited a positive correlation with HbA1c (P < .001) and a negative correlation with ankle-brachial index (P < .001). In the same group, patients with PAD had significantly higher MCP-1 levels compared with those without PAD (P < .001). In conclusion, T2DM patients with MetS exhibit higher serum MCP-1 levels. The latter is associated with worse glycemic control and PAD. These results suggest a potential contributory role for MCP-1 in the pathogenesis of PAD in the presence of hyperglycemia and MetS in T2DM.