Plasma urate concentration and risk of coronary heart disease: a Mendelian randomisation analysis

Association of genetically predicted 486 blood metabolites on the risk of Alzheimer's disease: a Mendelian randomization study

Background

Studies have reported that metabolic disturbance exhibits in patients with Alzheimer's disease (AD). Still, the presence of definitive evidence concerning the genetic effect of metabolites on AD risk remains insufficient. A systematic exploration of the genetic association between blood metabolites and AD would contribute to the identification of new targets for AD screening and prevention.

Methods

We conducted an exploratory two-sample Mendelian randomization (MR) study aiming to preliminarily identify the potential metabolites involved in AD development. A genome-wide association study (GWAS) involving 7,824 participants provided information on 486 human blood metabolites. Outcome information was obtained from a large-scale GWAS meta-analysis of AD, encompassing 21,982 cases and 41,944 controls of Europeans. The primary two-sample MR analysis utilized the inverse variance weighted (IVW) model while supplementary analyses used Weighted median (WM), MR Egger, Simple mode, and Weighted mode, followed by sensitivity analyses such as the heterogeneity test, horizontal pleiotropy test, and leave-one-out analysis. For the further identification of metabolites, replication and meta-analysis with FinnGen data, steiger test, linkage disequilibrium score regression, confounding analysis, and were conducted for further evaluation. Multivariable MR was performed to assess the direct effect of metabolites on AD. Besides, an extra replication analysis with EADB data was conducted for final evaluation of the most promising findings.

Results

After rigorous genetic variant selection, IVW, complementary analysis, sensitivity analysis, replication and meta-analysis with the FinnGen data, five metabolites (epiandrosterone sulfate, X-12680, pyruvate, docosapentaenoate, and 1-stearoylglycerophosphocholine) were identified as being genetically associated with AD. MVMR analysis disclosed that genetically predicted these four known metabolites can directly influence AD independently of other metabolites. Only epiandrosterone sulfate and X-12680 remained suggestive significant associations with AD after replication analysis with the EADB data.

Conclusion

By integrating genomics with metabonomics, this study furnishes evidence substantiating the genetic association of epiandrosterone sulfate and X-12680 with AD. These findings hold significance for the screening, prevention, and treatment strategies for AD.

A Ten-Year Follow-Up Study of the Association Between Uric Acid and Adverse Cardiovascular Events in Patients With Coronary Artery Disease

The association between uric acid (UA) and long-term mortality in patients with coronary artery disease is poorly investigated. We assessed the association between UA and 10-year mortality after percutaneous coronary intervention (PCI) in 3,998 patients who underwent PCI. Patients were categorized in groups according to UA tertiles: tertile 1 (UA <5.80 mg/100 ml, n = 1,347), tertile 2 (UA 5.80 to 7.04 mg/100 ml, n = 1,340), and tertile 3 (UA >7.94 mg/100 ml, n = 1,311). The primary outcome was 10-year all-cause mortality. All-cause deaths occurred in 1,200 patients: 320 deaths (26.5%) in patients with UA in the first tertile, 325 deaths (26.9%) in patients with UA in the second tertile, and 555 deaths (46.0%) in patients with UA in the third tertile (adjusted hazard ratio 1.22, 95% confidence interval 1.17 to 1.27, p <0.001) for 1 mg/100 ml increment in UA level. Cardiac deaths occurred in 748 patients: 194 deaths (16.5%) in patients with UA in the first tertile, 202 deaths (17.0%) in patients with UA in the second tertile, and 352 deaths (29.7%) in patients with UA in the third tertile (adjusted hazard ratio 1.24 [1.17 to 1.32], p <0.001) for 1 mg/100 ml increment in the UA level. The 10-year rates of target lesion revascularization, target vessel revascularization, or nontarget vessel revascularization did not differ significantly according to the UA level. In conclusion, in patients with coronary artery disease treated with PCI, increased UA level was associated with higher 10-year mortality. Increased UA level was not associated with the progression of atherosclerosis in nontreated coronary vessels or progression of intimal hyperplasia in stented lesions requiring intervention.

Mendelian randomization studies on coronary artery disease: a systematic review and meta-analysis

BACKGROUND

Coronary artery disease (CAD) remains one of the leading causes of mortality worldwide. We aimed to summarize what is currently known with regard to causal modifiable risk factors associated with CAD in populations of diverse ancestries through conducting a systematic review and meta-analysis of Mendelian randomization (MR) studies on CAD.

METHODS

The databases Embase, Medline, Cochrane Library and Web of Science were searched on the 19th and 20th of December 2022 for MR studies with CAD as a primary outcome; keywords of the search strategy included "coronary artery disease" and "mendelian randomization". Studies were included if they were published in the English language, included only human participants, employed Mendelian randomization as the primary methodology and studied CAD as the outcome of interest. The exclusion criteria resulted in the removal of studies that did not align with the predefined inclusion criteria, as well as studies which were systematic reviews themselves, and used the same exposure and outcome source as another study. An ancestry-specific meta-analysis was subsequently conducted on studies which investigated either body mass index, lipid traits, blood pressure or type 2 diabetes as an exposure variable. Assessment of publication bias and sensitivity analyses was conducted for risk of bias assessment in the included studies.

RESULTS

A total of 1781 studies were identified through the database searches after de-duplication was performed, with 47 studies included in the quantitative synthesis after eligibility screening. Approximately 80% of all included study participants for MR studies on CAD were of European descent irrespective of the exposure of interest, while no study included individuals of African ancestry. We found no evidence of differences in terms of direction of causation between ancestry groups; however, the strength of the respective relationships between each exposure and CAD were different, with this finding most evident when blood pressure was the exposure of interest.

CONCLUSIONS

Findings from this review suggest that patterns regarding the causational relationship between modifiable risk factors and CAD do not differ in terms of direction when compared across diverse ancestry populations. Differences in the observed strengths of the respective relationships however are indicative of the value of increasing representation in non-European populations, as novel genetic pathways or functional SNPs relating to CAD may be uncovered through a more global analysis.

SYSTEMATIC REVIEW REGISTRATION

The protocol for this systematic review was registered to the International Prospective Register of Systematic Reviews (PROSPERO) and is publicly available online (CRD42021272726).

Uric acid and evaluate the coronary vascular stenosis gensini score correlation research and in gender differences

BACKGROUND AND AIMS

Recent studies have shown that the negative effect of uric acid (UA) on coronary arteries determines the severity of atherosclerotic disease. This study aims to explore the relationship between serum UA level and Gensini score, which reflects the severity of coronary artery disease.

METHODS

A total of 860 patients with suspected coronary heart disease who were admitted to hospital due to angina pectoris or myocardial ischemia related symptoms and received coronary angiography were selected. Based on the findings of the angiography, they were categorized into two groups: the coronary heart disease (CHD) group (n = 625) and the control group (n = 235). The uric acid levels and other clinical data were compared between these groups. Additionally, the prevalence of coronary heart disease and Gensini score were compared between the groups, considering gender-specific quartiles of uric acid levels. The clinical baseline data were analyzed using appropriate statistical methods, and multivariate logistic regression analysis was conducted to identify independent risk factors for coronary heart disease.

RESULTS

Of 860 patients (mean age, 63.97 ± 11.87 years), 528 were men (mean age, 62.06 ± 11.5 years) and 332 were women (mean age, 66.99 ± 10.11 years). The proportion of smoking, diabetes, hypertension, and hyperlipidemia in the coronary heart disease group was higher than that in the control group (P < 0.05). HbA1C, Gensini score, BMI, TG and hsCRP in the coronary heart disease group were higher than those in the control group (P < 0.05), and HDL-C was lower than that in the control group (P < 0.05). There were no significant differences in age, heart rate, Cr, TC and LDL-C between the two groups (P > 0.05).Multivariate logistic regression analysis showed that age, hypertension, hsCRP and SUA levels increased the risk of coronary heart disease, and the difference was statistically significant(OR = 1.034,95%CI 1.016-1.052, P = 0.001; OR = 1.469,95%CI 1.007-2.142, P = 0.046;OR = 1.064,95%CI 1.026-1.105, P = 0.001; OR = 1.011,95%CI 1.008-1.014, P < 0.001).

CONCLUSION

Serum uric acid is positively correlated with Gensini score in patients with coronary heart disease, which is an independent factor for evaluating the degree of coronary artery stenosis and has a predictive effect.

Guidelines for performing Mendelian randomization investigations: update for summer 2023

This paper provides guidelines for performing Mendelian randomization investigations. It is aimed at practitioners seeking to undertake analyses and write up their findings, and at journal editors and reviewers seeking to assess Mendelian randomization manuscripts. The guidelines are divided into ten sections: motivation and scope, data sources, choice of genetic variants, variant harmonization, primary analysis, supplementary and sensitivity analyses (one section on robust statistical methods and one on other approaches), extensions and additional analyses, data presentation, and interpretation. These guidelines will be updated based on feedback from the community and advances in the field. Updates will be made periodically as needed, and at least every 24 months.

A Mendelian randomization study of serum uric acid with the risk of venous thromboembolism

BACKGROUND

Observational studies have linked hyperuricemia with venous thromboembolism (VTE). We aimed to investigate whether there are causal relationships between uric acid levels and VTE and its subtypes, including deep venous thrombosis (DVT) of the lower extremities and pulmonary embolism (PE).

METHODS

We utilized Mendelian randomization (MR) analysis to estimate the causal association in European individuals. We extracted two sets of polygenic instruments strongly associated (p < 5 × 10^-8) with uric acid from the CKDGen consortium and UK biobank, respectively. Genetic associations with the risk of VTE, DVT, and PE were obtained from the FinnGen biobank. We used the inverse-variance weighted method as the preliminary estimate. Additionally, we employed MR-Egger, weighted median, and Mendelian randomization pleiotropy residual sum and outlier method as complementary assessments. Sensitivity analyses were performed to test for pleiotropic bias.

RESULTS

The genetically instrumented serum uric acid levels had no causal effects on VTE, DVT, and PE. Two sets of polygenic instruments used for exposure, along with three complementary MR methods, also yielded no significant association.

CONCLUSIONS

Our MR analysis provided no compelling evidence for a causal relationship of serum uric acid with the risk of VTE. This suggests that uric acid-lowering therapies in patients with hyperuricemia may not be effective in reducing the likelihood of developing VTE.

Uric acid and risk of pre-eclampsia: results from a large case-control study and meta-analysis of prospective studies

To quantify the association between maternal uric acid levels and pre-eclampsia risk in a large collection of primigravid women. A case-control study (1365 cases of pre-eclampsia and 1886 normotensive controls) was conducted. Pre-eclampsia was defined as blood pressure ≥ 140/90 mmHg and proteinuria ≥ 300 mg/24 h. Sub-outcome analysis included early, intermediate, and late pre-eclampsia. Multivariable analysis for pre-eclampsia and its sub-outcomes was conducted using binary and multinomial logistic regression, respectively. Additionally, a systematic review and meta-analysis of cohort studies measuring uric acid levels < 20 weeks of gestation was performed to rule out reverse causation. There was a positive linear association between increasing uric acid levels and presence of pre-eclampsia. Adjusted odds ratio of pre-eclampsia was 1.21 (95%CI 1.11-1.33) for every one standard deviation increase in uric acid levels. No differences in the magnitude of association were observed between early and late pre-eclampsia. Three studies with uric acid measured < 20 weeks' gestation were identified, with a pooled OR for pre-eclampsia of 1.46 (95%CI 1.22-1.75) for a top vs. bottom quartile comparison. Maternal uric acid levels are associated with risk of pre-eclampsia. Mendelian randomisation studies would be helpful to further explore the causal role of uric acid in pre-eclampsia.

Mediating effect of metabolic diseases on the relationship between hyperuricemia and coronary heart disease

BACKGROUND AND AIMS

Studies have shown that elevated serum uric acid (SUA) may increase the risk of coronary heart disease (CHD). However, it is still disputable how mediate effects between metabolic diseases and hyperuricemia affect the incidence of CHD. This study aimed to explore whether metabolic diseases may mediate the connection from hyperuricemia at baseline to the elevated incidence risk of CHD during follow-ups.

METHODS AND RESULTS

Based on the Jinchang cohort, 48 001 subjects were followed for 9 years between June 2011 and December 2019. Multivariate-adjusted Cox regression models were applied to estimate hazard ratios (HRs) of CHD with 95% confidence intervals (CIs). Significantly increased risks of CHD were observed in hyperuricemia (HR:1.46, 95%CI:1.28, 1.67) when compared with normouricemia population. The mediating effect model further demonstrated that metabolic diseases could mediate the association between hyperuricemia and CHD pathogenesis, partially for the combined metabolic diseases with mediation effects of 45.12%, 25.24% for hypertension, 28.58% for overweight or obese status, 29.05% for hypertriglyceridemia, 6.70% for hypercholesterolemia, 3.52% for low high density lipoprotein cholesterol (HDL-C), and 6.51% for high low density lipoprotein cholesterol (LDL-C), respectively.

CONCLUSIONS

Hyperuricemia significantly increased the risk of incident CHD, and this association was partly mediated by metabolic diseases.

NRBP1 modulates uric acid transporter ABCG2 expression by activating the Wnt/β-catenin pathway in HK-2 cells

BACKGROUND

Nuclear receptor binding protein 1 (NRBP1) and ATP-binding cassette subfamily G member 2 (ABCG2) was the gout risk gene and high-capacity urate exporter respectively. However, the relationship between NRBP1 and ABCG2 and the underlying molecular mechanism contributing to these associations are unknown.

METHODS

Firstly, the efficiency of the overexpression and knockdown of NRBP1 was confirmed by western blot. Next, the effect of NRBP1 overexpression and knockdown on the expression of ABCG2, organic anion transporter 1 (OAT1), glucose transporter 9 (GLUT9) and urate transporter 1 (URAT1) was detected by qRT-PCR and western blot. At the same time, the cellular location of ABCG2 and its expression after NRBP1 overexpression and knockdown was tested by immunofluorescence (IF) staining. Then, the mechanism of NRBP1 modulates ABCG2 expression was evaluated by western blot with or without the β-catenin inhibitor (21H7).

RESULTS

The lentivirus system was used to generate stable NRBP1 overexpression, while the plasmids carrying a NRBP1 siRNA was generated to knockdown NRBP1 expression in HK-2 cells. Meanwhile, the overexpression of NRBP1 significantly decreased the mRNAs and proteins expression of GLUT9 and URAT1, while the knockdown of NRBP1 increased the mRNAs and proteins expression of ABCG2 significantly. In addition, the NRBP1 modulates the expression of ABCG2 was by ctivating the Wnt/β-catenin pathway in HK-2 cells according to the IF and western blot results.

CONCLUSION

Taken together, our study demonstrated that NRBP1 inhibition played an essential role in attenuating hyperuricemia and gout by upregulation of ABCG2 via Wnt/β-catenin signaling pathway in HK-2 cells.

Hyperuricemia and gout: effects on bone and articular cartilage (literature review)

Gout is a disease characterized by deposition of sodium monourate crystals in tissues which is the reason of inflammation among persons with hyperuricemia (HU). The prevalence of HU, which can be considered the first stage of gout formation, varies in different countries. Despite this, only a small number of persons with HU have been shown to develop symptoms of gout. Recent data suggest that HU is an independent risk factor for cartilage and bone damage. UA, both in the form of crystals and in a dissolved form, activates damage and potentiates cell death by releasing reactive oxygen species, activating the necroptosis pathway, neutrophil traps, synthesis of pro-inflammatory cytokines, and other pathogenetic mechanisms that cause the negative effects of HU and gout on articular cartilage and subchondral bone. The association of HU and osteoarthritis (OA) is well known and based on the common pathogenesis, but the direction of this relationship is still a debatable issue. The accumulated data suggest the need for a deeper study of the relationship of gout and asymptomatic HU with pathological processes leading to the development and progression of OA and disorders of bone metabolism.

Weak Association Between Genetic Markers of Hyperuricemia and Cardiorenal Outcomes: Insights From the STANISLAS Study Cohort With a 20-Year Follow-Up

Background

Hyperuricemia is associated with poor cardiovascular outcomes, although it is uncertain whether this relationship is causal in nature. This study aimed to: (1) assess the heritability of serum uric acid (SUA) levels, (2) conduct a genome‐wide association study on SUA levels, and (3) investigate the association between certain single‐nucleotide polymorphisms and target organ damage.

Methods and Results

The STANISLAS (Suivi Temporaire Annuel Non‐Invasif de la Santé des Lorrains Assurés Sociaux) study cohort is a single‐center longitudinal cohort recruited between 1993 and 1995 (visit 1), with a last visit (visit 4 [V4]) performed ≈20 years apart. Serum lipid profile, SUA, urinary albumin/creatinine ratio, estimated glomerular filtration rate, 24‐hour ambulatory blood pressure monitoring, transthoracic echocardiography, pulse wave velocity, and genotyping for each participant were assessed at V4. A total of 1573 participants were included at V4, among whom 1417 had available SUA data at visit 1. Genome‐wide association study results highlighted multiple single‐nucleotide polymorphisms on the SLC2A9 gene linked to SUA levels. Carriers of the most associated mutated SLC2A9 allele (rs16890979) had significantly lower SUA levels. Although SUA level at V4 was highly associated with diabetes, prediabetes, higher body mass index, CRP (C‐reactive protein) levels, estimated glomerular filtration rate variation (visit 1–V4), carotid intima‐media thickness, and pulse wave velocity, rs16890979 was only associated with higher carotid intima‐media thickness.

Conclusions

Our findings demonstrate that rs16890979, a genetic determinant of SUA levels located on the SLC2A9 gene, is associated with carotid intima‐media thickness despite significant associations between SUA levels and several clinical outcomes, thereby lending support to the hypothesis of a link between SUA and cardiovascular disease.

Impact of serum uric acid levels on cardiovascular events and quality of life in patients with chronic coronary syndromes: Insights from a contemporary, prospective, nationwide registry

BACKGROUND AND AIMS

Hyperuricemia is a metabolic disorder that has been associated with adverse cardiovascular (CV) events. Using the data from a nationwide, prospective registry on patients with chronic coronary syndromes (CCS), we assessed the impact of serum uric acid (SUA) levels on quality of life (QoL) and major adverse CV events (MACE), a composite of CV death and hospitalization for myocardial infarction, heart failure (HF), angina or revascularization at 1-year.

METHODS AND RESULTS

Among the 5070 consecutive CCS patients enrolled in the registry, levels of SUA were available for 2394 (47.2%). Patients with SUA levels available at baseline were grouped as low tertile (n = 860; 4.3 [3.7-4.7] mg/dL), middle tertile (n = 739; 5.6 [5.3-5.9] mg/dL) and high tertile (n = 795; 7.1 [6.7-7.9] mg/dL). At 1 year, the incidence of MACE was 3.7%, 4.1% and 6.8% for low, middle and high tertiles, respectively (p = 0.005 for low vs high tertile). Patients in the high tertile of SUA had a significantly higher rate of CV mortality (1.4% vs 0.4%; p = 0.05) and hospital admission for HF (2.8% vs 1.6%; p = 0.03) compared to the low tertile. However, hyperuricemia did not result as an independent predictor of MACE at multivariable analysis [hazard ratio: 1.27; 95% confidence intervals: 0.81-2.00; p = 0.3].

CONCLUSIONS

In this contemporary, large cohort of CCS, those in the high tertile of SUA had a greater burden of CV disease and worse QoL. However, SUA did not significantly influence the higher rate of CV mortality, hospitalization for HF and MACE observed in these patients during 1-year follow-up.

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.

Prevalence of asymptomatic hyperuricemia and its association with prediabetes, dyslipidemia and subclinical inflammation markers among young healthy adults in Qatar

AIM

The aim of this study is to investigate the prevalence of asymptomatic hyperuricemia in Qatar and to examine its association with changes in markers of dyslipidemia, prediabetes and subclinical inflammation.

METHODS

A cross-sectional study of young adult participants aged 18 - 40 years old devoid of comorbidities collected between 2012 and 2017. Exposure was defined as uric acid level, and outcomes were defined as levels of different blood markers. De-identified data were collected from Qatar Biobank. T-tests, correlation tests and multiple linear regression were all used to investigate the effects of hyperuricemia on blood markers. Statistical analyses were conducted using STATA 16.

RESULTS

The prevalence of asymptomatic hyperuricemia is 21.2% among young adults in Qatar. Differences between hyperuricemic and normouricemic groups were observed using multiple linear regression analysis and found to be statistically and clinically significant after adjusting for age, gender, BMI, smoking and exercise. Significant associations were found between uric acid level and HDL-c p = 0.019 (correlation coefficient -0.07 (95% CI [-0.14, -0.01]); c-peptide p = 0.018 (correlation coefficient 0.38 (95% CI [0.06, 0.69]) and monocyte to HDL ratio (MHR) p = 0.026 (correlation coefficient 0.47 (95% CI [0.06, 0.89]).

CONCLUSIONS

Asymptomatic hyperuricemia is prevalent among young adults and associated with markers of prediabetes, dyslipidemia, and subclinical inflammation.

Relationship Between Four Non-Insulin-Based Indexes of Insulin Resistance and Serum Uric Acid in Patients with Type 2 Diabetes: A Cross-Sectional Study

AIM

The aim of this study was to investigate the association between serum uric acid (SUA) levels and four insulin resistance surrogates in patients with type 2 diabetes (T2DM). The four non-insulin-based indexes of insulin resistance (IR) include the glucose and triglycerides index (TyG), TyG index with body mass index (TyG-BMI), ratio of triglycerides to high-density lipoprotein cholesterol (TG/HDL-c) and metabolic score for insulin resistance (METS-IR).

METHODS

A total of 687 patients with T2DM were enrolled in the current study. Patients were stratified into three groups according to their levels of SUA. Spearman correlation was used to analyze the correlation between SUA and clinical variables. Multiple linear regression analysis was used to assess the association between SUA and the four insulin resistance surrogates. Receiver operating characteristic (ROC) analyses and the area under the ROC curve (AUC) were then used to assess the ability of TyG, TyG-BMI, TG/HDL-c, and METS-IR to discriminate hyperuricemia (HUA) in T2DM.

RESULTS

SUA in T2DM was significantly positively correlated with TyG (r 0.406 P < 0.01), TyG-BMI (r 0.272 P < 0.01), TG/HDL-c (r 0.493 P < 0.01), and METS-IR (r 0.238 P < 0.01). Furthermore, higher values of the four insulin resistance surrogates were independently correlated with higher SUA levels in T2DM patients (P < 0.01 for all) after adjusting for confounding factors. TyG, TyG-BMI, TG/HDL-c, and METS-IR all had a significant discriminative ability for HUA in patients with T2DM. The AUC values were 0.693 (95% CI 0.645-0.741), 0.649 (95% CI 0.599-0.699), 0.768 (95% CI 0.726-0.811), and 0.660 (95% CI 0.609-0.710), respectively.

CONCLUSION

The present study suggests that TyG, TyG-BMI, TG/HDL-c and METS-IR had a significant correlation with SUA in T2DM. TG/HDL-c was the best marker among the four insulin resistance surrogates for the identification of HUA in T2DM.

Clinical Efficacy of Multidomain Interventions among Multimorbid Older People Stratified by the Status of Physio-Cognitive Declines: A Secondary Analysis from the Randomized Controlled Trial for Healthy Aging

OBJECTIVES

To investigate the clinical efficacy of integrated multidomain intervention among community-living older adults with multimorbidity and physio-cognitive decline syndrome (PCDS).

DESIGN, SETTING AND PARTICIPANTS

This is the secondary analysis from a randomized controlled trial that data of 340 participants with Montreal Cognitive Assessment (MoCA) scores≥18 were excerpted for analysis.

INTERVENTION

Sixteen 2-hour sessions per year were provided for participants, including physical exercise, cognitive training, dietician education and individualized integrated care for multimorbidity.

MEASUREMENTS

Handgrip strength, 6-m walking speed, MoCA (total score and sub-domains), Cardiovascular Health Study (CHS) frailty score, quality of life, and serum biochemistry biomarkers.

RESULTS

Overall, 96/340 (28.2%) of all participants have PCDS, and the integrated multidomain intervention significantly improved global cognitive performance (overall difference 1.1, 95% CI 0.4 - 1.8, p=0.003), and domains of concentration (overall difference 0.3, 95%CI 0.1 - 0.5, p=0.011), language (overall difference 0.2, 95%CI 0.1 - 0.3, p=0.006), abstract thinking (overall difference 0.1, 95%CI 0.0 - 0.3, p=0.027), and orientation(overall difference 0.2, 95%CI 0.0 - 0.4, p=0.013) across all timepoints among those with PCDS. Besides, interventions also significantly reduced frailty score among those with cognitive impairment no dementia (overall difference -0.3, 95%CI -0.5 - -0.1, p=0.011) and mobility impairment no disability (overall difference -0.3, 95%CI -0.4 - -0.1, p=0.004). and improved quality of life at domain of physical role limitation among those with PCDS (overall difference 5.3, 95%CI 0.3 - 10.4, p=0.038).

CONCLUSIONS

The integrated multidomain lifestyle intervention plus multimorbidity management significantly improved cognitive function, and enhanced quality of life among older adults with multimorbidity and PCDS in the communities.

Modulation of Vascular Smooth Muscle Cell Multiplication, Apoptosis, and Inflammatory Damage by miR-21 in Coronary Heart Disease

This study is aimed at exploring the role and potential molecular mechanism of microRNA-21 (miR-21) in coronary heart disease (CHD). RT-qPCR analysis was conducted to detect the expression of miR-21, Sprouty 1 (SPRY1), and connexin 43 (CX43). The protein expression of SPRY1 and CX43 was measured by western blot. ELISA was performed for measuring inflammatory factors, including intercellular adhesion molecule-1 (ICAM-1) and interleukin-1 beta (IL-1β). The target relationship between miR-21 and SPRY1 was determined by dual-luciferase reporter assay. Cell multiplication and apoptosis were detected using CCK-8 assay and flow cytometry analysis, respectively. Our results indicated that miR-21, CX43, and the level of inflammatory cytokines including ICAM-1 and IL-1β were upregulated, while SPRY1 was downregulated in blood samples from CHD patients compared with the controls. Besides, miR-21 directly targeted SRPY-1. miR-21 could suppress SPRY1 expression and enhance CX43 expression in VSMCs. Moreover, miR-21 accelerated cell multiplication and attenuated cell apoptosis in VSMCs. Collectively, these findings suggested that miR-21 could effectively elevate VSMC multiplication and repress apoptosis by targeting SPRY1 in CHD, providing a potential target for therapeutic strategy of CHD.

Assessing the Causal Relationships Between Insulin Resistance and Hyperuricemia and Gout Using Bidirectional Mendelian Randomization

OBJECTIVE

Hyperuricemia is closely associated with insulin resistance syndrome (and its many cardiometabolic sequelae); however, whether they are causally related has long been debated. We undertook this study to investigate the potential causal nature and direction between insulin resistance and hyperuricemia, along with gout, by using bidirectional Mendelian randomization (MR) analyses.

METHODS

We used genome-wide association data (n = 288,649 for serum urate [SU] concentration; n = 763,813 for gout risk; n = 153,525 for fasting insulin) to select genetic instruments for 2-sample MR analyses, using multiple MR methods to address potential pleiotropic associations. We then used individual-level, electronic medical record-linked data from the UK Biobank (n = 360,453 persons of European ancestry) to replicate our analyses via single-sample MR analysis.

RESULTS

Genetically determined SU levels, whether inferred from a polygenic score or strong individual loci, were not associated with fasting insulin concentrations. In contrast, genetically determined fasting insulin concentrations were positively associated with SU levels (0.37 mg/dl per log-unit increase in fasting insulin [95% confidence interval (95% CI) 0.15, 0.58]; P = 0.001). This persisted in outlier-corrected (β = 0.56 mg/dl [95% CI 0.45, 0.67]) and multivariable MR analyses adjusted for BMI (β = 0.69 mg/dl [95% CI 0.53, 0.85]) (P < 0.001 for both). Polygenic scores for fasting insulin were also positively associated with SU level among individuals in the UK Biobank (P < 0.001). Findings for gout risk were bidirectionally consistent with those for SU level.

CONCLUSION

These findings provide evidence to clarify core questions about the close association between hyperuricemia and insulin resistance syndrome: hyperinsulinemia leads to hyperuricemia but not the other way around. Reducing insulin resistance could lower the SU level and gout risk, whereas lowering the SU level (e.g., allopurinol treatment) is unlikely to mitigate insulin resistance and its cardiometabolic sequelae.

Can biomarkers be used to improve diagnosis and prediction of metabolic syndrome in childhood cancer survivors? A systematic review

Childhood cancer survivors (CCS) are at increased risk to develop metabolic syndrome (MetS), diabetes, and cardiovascular disease. Common criteria underestimate adiposity and possibly underdiagnose MetS, particularly after abdominal radiotherapy. A systematic literature review and meta-analysis on the diagnostic and predictive value of nine newer MetS related biomarkers (adiponectin, leptin, uric acid, hsCRP, TNF-alpha, IL-1, IL-6, apolipoprotein B (apoB), and lipoprotein(a) [lp(a)]) in survivors and adult non-cancer survivors was performed by searching PubMed and Embase. Evidence was summarized with GRADE after risk of bias evaluation (QUADAS-2/QUIPS). Eligible studies on promising biomarkers were pooled. We identified 175 general population and five CCS studies. In the general population, valuable predictive biomarkers are uric acid, adiponectin, hsCRP and apoB (high level of evidence), and leptin (moderate level of evidence). Valuable diagnostic biomarkers are hsCRP, adiponectin, uric acid, and leptin (low, low, moderate, and high level of evidence, respectively). Meta-analysis showed OR for hyperuricemia of 2.94 (age-/sex-adjusted), OR per unit uric acid increase of 1.086 (unadjusted), and AUC for hsCRP of 0.71 (unadjusted). Uric acid, adiponectin, hsCRP, leptin, and apoB can be alternative biomarkers in the screening setting for MetS in survivors, to enhance early identification of those at high risk of subsequent complications.

SLC17A3 rs9379800 and Ischemic Stroke Susceptibility at the Northern Region of Malaysia

OBJECTIVES

The relationships of Paired Like Homeodomain 2 (PITX2), Ninjurin 2 (NINJ2), TWIST-Related Protein 1 (TWIST1), Ras Interacting Protein 1 (Rasip1), Solute Carrier Family 17 Member 3 (SLC17A3), Methylmalonyl Co-A Mutase (MUT) and Fer3 Like BHLH Transcription Factor (FERD3L) polymorphisms and gene expression with ischemic stroke have yet to be determined in Malaysia. Hence, this study aimed to explore the associations of single nucleotide polymorphisms (SNPs) and gene expression with ischemic stroke risk among population who resided at the Northern region of Malaysia.

MATERIALS AND METHODS

Study subjects including 216 ischemic stroke patients and 203 healthy controls were recruited upon obtaining ethical clearance. SNP genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism assays. Gene expression levels were quantified by real-time polymerase chain reaction assays. Statistical and genetic analyses were conducted with SPSS version 22.2, PLINK version 1.07 and multifactor dimensionality reduction software.

RESULTS

Study subjects with G allele, CG or GG genotypes of SLC17A3 rs9379800 demonstrated increased risk of ischemic stroke with the odds ratios ranging from 1.76-fold to 3.14-fold (p<0.05). When stratified study subjects according to the ethnicity, SLC17A3 rs9379800 G allele and CG genotype contributed to 2.14- and 2.96-fold of ischemic stroke risk among Malay population significantly, in the multivariate analysis (p<0.05). However, no significant associations were observed for PITX2, NINJ2, TWIST1, Rasip1, and MUT polymorphisms with ischemic stroke risk in the multivariate analysis for the pooled cases and controls as well as when stratified them according to the ethnicity. Lower mRNA expression levels of Rasip1, SLC17A3, MUT and FERD3L were observed among cases (p<0.05). After FDR adjustment, the mRNA level of SLC17A3 remained significantly associated with ischemic stroke among Malay population (q=0.034).

CONCLUSION

In conclusion, this study suggests that SLC17A3 rs9379800 polymorphism and its gene expression contribute to significant ischemic stroke risk among Malaysian population, particularly the Malay who resided at the Northern Region of the country. Our findings can provide useful information for the future diagnosis, management and treatment of ischemic stroke patients.

Causal Associations of Urate With Cardiovascular Risk Factors: Two-Sample Mendelian Randomization

Background

Mendelian Randomization (MR) studies show conflicting causal associations of genetically predicted serum urate with cardiovascular risk factors (i.e., hypertension, diabetes, lipid profile, and kidney function). This study aimed to robustly investigate a causal relationship between urate and cardiovascular risk factors considering single nucleotide polymorphisms (SNPs) as instrumental variables using two-sample MR and various sensitivity analyses.

Methods

Data on SNP-urate associations were taken from the Global Urate Genetics Consortium and data on SNP-cardiovascular risk factor associations were taken from various consortia/UK Biobank. SNPs were selected by statistically and biologically driven approaches as instrumental variables. Various sensitivity analyses were performed using different MR methods including inverse variance weighted, MR-Egger, weighted median/mode, MR-PRESSO, and the contamination mixture method.

Results

The statistically driven approach showed significant causal effects of urate on HDL-C and triglycerides using four of the six MR methods, i.e., every 1 mg/dl increase in genetically predicted urate was associated with 0.047 to 0.103 SD decrease in HDL-C and 0.034 to 0.207 SD increase in triglycerides. The biologically driven approach to selection of SNPs from ABCG2, SLC2A9, SLC17A1, SLC22A11, and SLC22A12 showed consistent causal effects of urate on HDL-C from all methods with 0.038 to 0.057 SD decrease in HDL-C per 1 mg/dl increase of urate, and no evidence of horizontal pleiotropy was detected.

Conclusion

Our study suggests a significant and robust causal effect of genetically predicted urate on HDL-C. This finding may explain a small proportion (7%) of the association between increased urate and cardiovascular disease but points to urate being a novel cardiac risk factor.

Mendelian Randomisation Finds No Causal Association between Urate and Parkinson's Disease Progression

BACKGROUND

Parkinson's disease (PD) is a common neurodegenerative movement disorder. Observational studies suggest higher levels of plasma urate may protect against Parkinson's risk and progression; however, causality cannot be established.

OBJECTIVES

This study set out to determine whether there is a true causal association between urate levels and PD age at onset (AAO) and progression severity using recently released PD AAO and progression genome-wide association study (GWAS) data.

METHODS

A large two-sample Mendelian randomization design was employed, using genetic variants underlying urate levels and the latest GWAS data for PD outcomes.

RESULTS

This study found no causal association between urate levels and Parkinson's risk, AAO, or progression severity.

CONCLUSIONS

Our results predict increasing urate levels as a therapeutic strategy is unlikely to benefit PD patients. © 2021 International Parkinson and Movement Disorder Society.

Uric Acid-An Emergent Risk Marker for Thrombosis?

Hyperuricemia is nowadays an established cardiovascular risk factor. Experimental studies linked elevated serum uric acid (SUA) levels with endothelial dysfunction (ED), inflammation, and prothrombotic state. The purpose of this review is to summarize the current evidence that emphasizes the possible role of uric acid as a biomarker for a prothrombotic state. A large number of clinical trials correlated SUA levels with both incident and recurrent cases of venous thromboembolism (VTE), independent of other confounding risk factors. Moreover, increased SUA levels may be an important tool for the risk stratification of patients with pulmonary embolism (PE). Left atrial thrombosis was correlated with high SUA levels in several studies and its addition to classical risk scores improved their predictive abilities. In patients with acute myocardial infarction (MI), hyperuricemia was associated with increased mortality, and the idea that hyperuricemia may be able to act as a surrogate to unstable coronary plaques was advanced. Finally, SUA was correlated with an increased risk of thromboembolic events in different systemic diseases. In conclusion, uric acid has been considered a marker of a thrombotic milieu in several clinical scenarios. However, this causality is still controversial, and more experimental and clinical data is needed.

Urate, Blood Pressure, and Cardiovascular Disease: Evidence From Mendelian Randomization and Meta-Analysis of Clinical Trials

Serum urate has been implicated in hypertension and cardiovascular disease, but it is not known whether it is exerting a causal effect. To investigate this, we performed Mendelian randomization analysis using data from UK Biobank, Million Veterans Program and genome-wide association study consortia, and meta-analysis of randomized controlled trials. The main Mendelian randomization analyses showed that every 1-SD increase in genetically predicted serum urate was associated with an increased risk of coronary heart disease (odds ratio, 1.19 [95% CI, 1.10-1.30]; P=4×10-5), peripheral artery disease (1.12 [95% CI, 1.03-1.21]; P=9×10-3), and stroke (1.11 [95% CI, 1.05-1.18]; P=2×10-4). In Mendelian randomization mediation analyses, elevated blood pressure was estimated to mediate approximately one-third of the effect of urate on cardiovascular disease risk. Systematic review and meta-analysis of randomized controlled trials showed a favorable effect of urate-lowering treatment on systolic blood pressure (mean difference, -2.55 mm Hg [95% CI, -4.06 to -1.05]; P=1×10-3) and major adverse cardiovascular events in those with previous cardiovascular disease (odds ratio, 0.40 [95% CI, 0.22-0.73]; P=3×10-3) but no significant effect on major adverse cardiovascular events in all individuals (odds ratio, 0.67 [95% CI, 0.44-1.03]; P=0.07). In summary, these Mendelian randomization and clinical trial data support an effect of higher serum urate on increasing blood pressure, which may mediate a consequent effect on cardiovascular disease risk. High-quality trials are necessary to provide definitive evidence on the specific clinical contexts where urate lowering may be of cardiovascular benefit.

Allopurinol and Renal Outcomes in Adults With and Without Type 2 Diabetes: A Retrospective, Population-Based Cohort Study and Propensity Score Analysis

OBJECTIVES

Elevated uric acid (UA) is common in diabetes and is implicated in the pathogenesis of chronic kidney disease (CKD). Lowering UA with allopurinol may delay CKD progression. We assessed the association between allopurinol and renal outcomes in older adults both with and without diabetes, and whether this differed by diabetes status.

METHODS

We conducted a population-based, retrospective cohort study of older adults ≥66 years of age with a gout flare using administrative data from Ontario, Canada. The primary outcome was doubling of creatinine or kidney failure. Secondary outcomes were a composite of death or kidney failure, decline in estimated glomerular filtration rate by >30%, death and kidney failure. New allopurinol users were compared with nonusers using Cox proportional hazards models and inverse probability of treatment weighting (IPTW). An interaction between allopurinol use and presence or absence of diabetes was assessed.

RESULTS

Among 5,937 older adults with a gout flare (1,911 with diabetes), 1,304 (22%) were newly treated with allopurinol. Median follow-up time was 1.11 (interquartile range, 0.33 to 3.21) years for allopurinol users and 3.38 (interquartile range, 1.42 to 4.43) years for nonusers. There was no association between allopurinol use and the primary outcome (IPTW-adjusted hazard ratio, 0.97; 95% confidence interval, 0.72 to 1.31), and this did not differ by diabetes status. Allopurinol use was not associated with any of the secondary outcomes.

CONCLUSIONS

Allopurinol use was not associated with renal outcomes in older adults with or without diabetes. This supports the interpretation of UA as a biomarker of CKD risk rather than a modifiable target for prevention or treatment of CKD.

Survey on uric acid in Chinese subjects with essential hypertension (SUCCESS): a nationwide cross-sectional study

Background

Hyperuricemia (HUA) is associated with hypertension and increased cardiovascular risk. Current data regarding the prevalence of HUA in Chinese hypertensive patients are lacking. Our study aims to explore the prevalence and determinants of HUA in Chinese hypertensive adults.

Methods

Treatment-naive hypertensive adults or those taking single antihypertensive agent were included in a nationwide cross-sectional study. Basic demographics, antihypertensive medications, serum uric acid (UA), and other parameters were documented.

Results

The overall prevalence rate of HUA was 38.7% among 33,785 valid cases, 35.1% for males (UA >420 µmol/L), and 45.2% for females (UA >360 µmol/L). A multiple logistic regression analysis, adjusted for demographic and clinical factors (model 1), revealed that female sex [odds ratio (OR), 95% CI, 1.43, 1.36–1.51], age of ≥65 years (1.12, 1.05–1.19), low evaluated glomerular filtration rate [eGFR; 2.06, 1.91–2.23, the lowest [Q1] vs. the highest quartile (Q4)], unmarried (1.58, 1.10–2.27), Western China residency (3.21, 3.33–3.91), longer hypertension duration (1.97, 1.78–2.12, Q4 vs. Q1) and aspirin use (1.21, 1.14–1.29) were associated with HUA. In a multiple logistic regression analysis adjusted for clinical and metabolic parameters (model 2), female sex (OR, 95% CI, 1.34, 1.27–1.41), age of ≥65 years (1.09, 1.03–1.16), low eGFR (2.35, 2.19–2.52, Q1 vs. Q4), new–onset hypertension (2.01, 1.73–2.33), higher quartile of fasting blood glucose (FBG), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) levels, and body mass index (BMI) were associated with higher risk of HUA (1.89, 1.76–2.03; 2.15, 1.99–2.31; 2.86, 2.67–3.06; 1.27, 1.27–1.36, respectively, Q4 vs. Q1). Losartan, valsartan, and nifedipine were associated with lower risk of HUA (OR, 95% CI, 0.77, 0.67–0.88, 0.68, 0.60–0.77; 0.87, 0.77–0.99, 0.79, 0.70–0.89 and 0.80, 0.70–0.91, 0.82, 0.72–0.92), respectively, in models 1 and 2.

Conclusions

The prevalence rate of HUA in Chinese hypertensive patients was 38.7%. Female sex, aging (≥65 years), and low eGFR were independent predictors of HUA. HUA was lower among the patients who were taking losartan, valsartan, and nifedipine. Western region residents, new-onset hypertension, longer hypertension duration, aspirin use, higher FBG, TG, LDL-C levels and BMI were potential risk factors for HUA.

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.

Serum Uric Acid Concentrations and Risk of Adverse Outcomes in Patients With COVID-19

BACKGROUND

Although hyperuricemia frequently associates with respiratory diseases, patients with severe coronavirus disease 2019 (COVID-19) and severe acute respiratory syndrome (SARS) can show marked hypouricemia. Previous studies on the association of serum uric acid with risk of adverse outcomes related to COVID-19 have produced contradictory results. The precise relationship between admission serum uric acid and adverse outcomes in hospitalized patients is unknown.

METHODS

Data of patients affected by laboratory-confirmed COVID-19 and admitted to Leishenshan Hospital were retrospectively analyzed. The primary outcome was composite and comprised events, such as intensive care unit (ICU) admission, mechanical ventilation, or mortality. Logistic regression analysis was performed to explore the association between serum concentrations of uric acid and the composite outcome, as well as each of its components. To determine the association between serum uric acid and in-hospital adverse outcomes, serum uric acid was also categorized by restricted cubic spline, and the 95% confidence interval (CI) was used to estimate odds ratios (OR).

RESULTS

The study cohort included 1854 patients (mean age, 58 years; 52% women). The overall mean ± SD of serum levels of uric acid was 308 ± 96 µmol/L. Among them, 95 patients were admitted to ICU, 75 patients received mechanical ventilation, and 38 died. In total, 114 patients reached composite end-points (have either ICU admission, mechanical ventilation or death) during hospitalization. Compared with a reference group with estimated baseline serum uric acid of 279-422 µmol/L, serum uric acid values ≥ 423 µmol/L were associated with an increased risk of composite outcome (OR, 2.60; 95% CI, 1.07- 6.29) and mechanical ventilation (OR, 3.01; 95% CI, 1.06- 8.51). Serum uric acid ≤ 278 µmol/L was associated with an increased risk of the composite outcome (OR, 2.07; 95% CI, 1.18- 3.65), ICU admission (OR, 2.18; 95% CI, 1.17- 4.05]), and mechanical ventilation (OR, 2.13; 95% CI, 1.06- 4.28), as assessed by multivariate analysis.

CONCLUSIONS

This study shows that the association between admission serum uric acid and composite outcome of COVID-19 patients was U-shaped. In particular, we found that compared with baseline serum uric acid levels of 279-422 µmol/L, values ≥ 423 µmol/L were associated with an increased risk of composite outcome and mechanical ventilation, whereas levels ≤ 278 µmol/L associated with increased risk of composite outcome, ICU admission and mechanical ventilation.

Uric acid and cardiovascular disease: A clinical review

Uric acid, the end-product of purine metabolism in humans, is not only a cause of gout, but also may play roles in developing cardiovascular diseases such as hypertension, atrial fibrillation, chronic kidney disease, heart failure, coronary artery disease, and cardiovascular death. Several clinical investigations have reported serum uric acid as a predictive marker for cardiovascular outcomes. Although the causal relationship of hyperuricemia to cardiovascular diseases remains controversial, there has been a growing interest in uric acid because of the increased prevalence of hyperuricemia worldwide. This review article summarizes current evidence concerning the relation between hyperuricemia and cardiovascular diseases.

Long-term cardiovascular safety of febuxostat compared with allopurinol in patients with gout (FAST): a multicentre, prospective, randomised, open-label, non-inferiority trial

BACKGROUND

Febuxostat and allopurinol are urate-lowering therapies used to treat patients with gout. Following concerns about the cardiovascular safety of febuxostat, the European Medicines Agency recommended a post-licensing study assessing the cardiovascular safety of febuxostat compared with allopurinol.

METHODS

We did a prospective, randomised, open-label, blinded-endpoint, non-inferiority trial of febuxostat versus allopurinol in patients with gout in the UK, Denmark, and Sweden. Eligible patients were 60 years or older, already receiving allopurinol, and had at least one additional cardiovascular risk factor. Those who had myocardial infarction or stroke in the previous 6 months or who had severe congestive heart failure or severe renal impairment were excluded. After a lead-in phase in which allopurinol dose was optimised towards achieving a serum urate concentration of less than 0·357 mmol/L (<6 mg/dL), patients were randomly assigned (1:1, with stratification according to previous cardiovascular events) to continue allopurinol (at the optimised dose) or start febuxostat at 80 mg/day, increasing to 120 mg/day if necessary to achieve the target serum urate concentration. The primary outcome was a composite of hospitalisation for non-fatal myocardial infarction or biomarker-positive acute coronary syndrome; non-fatal stroke; or cardiovascular death. The hazard ratio (HR) for febuxostat versus allopurinol in a Cox proportional hazards model (adjusted for the stratification variable and country) was assessed for non-inferiority (HR limit 1·3) in an on-treatment analysis. This study is registered with the EU Clinical Trials Register (EudraCT 2011-001883-23) and ISRCTN (ISRCTN72443728) and is now closed.

FINDINGS

From Dec 20, 2011, to Jan 26, 2018, 6128 patients (mean age 71·0 years [SD 6·4], 5225 [85·3%] men, 903 [14·7%] women, 2046 [33·4%] with previous cardiovascular disease) were enrolled and randomly allocated to receive allopurinol (n=3065) or febuxostat (n=3063). By the study end date (Dec 31, 2019), 189 (6·2%) patients in the febuxostat group and 169 (5·5%) in the allopurinol group withdrew from all follow-up. Median follow-up time was 1467 days (IQR 1029-2052) and median on-treatment follow-up was 1324 days (IQR 870-1919). For incidence of the primary endpoint, on-treatment, febuxostat (172 patients [1·72 events per 100 patient-years]) was non-inferior to allopurinol (241 patients [2·05 events per 100 patient-years]; adjusted HR 0·85 [95% CI 0·70-1·03], p<0·0001). In the febuxostat group, 222 (7·2%) of 3063 patients died and 1720 (57·3%) of 3001 in the safety analysis set had at least one serious adverse event (with 23 events in 19 [0·6%] patients related to treatment). In the allopurinol group, 263 (8·6%) of 3065 patients died and 1812 (59·4%) of 3050 had one or more serious adverse events (with five events in five [0·2%] patients related to treatment). Randomised therapy was discontinued in 973 (32·4%) patients in the febuxostat group and 503 (16·5%) patients in the allopurinol group.

INTERPRETATION

Febuxostat is non-inferior to allopurinol therapy with respect to the primary cardiovascular endpoint, and its long-term use is not associated with an increased risk of death or serious adverse events compared with allopurinol.

FUNDING

Menarini, Ipsen, and Teijin Pharma Ltd.

An efficient and robust approach to Mendelian randomization with measured pleiotropic effects in a high-dimensional setting

Valid estimation of a causal effect using instrumental variables requires that all of the instruments are independent of the outcome conditional on the risk factor of interest and any confounders. In Mendelian randomization studies with large numbers of genetic variants used as instruments, it is unlikely that this condition will be met. Any given genetic variant could be associated with a large number of traits, all of which represent potential pathways to the outcome which bypass the risk factor of interest. Such pleiotropy can be accounted for using standard multivariable Mendelian randomization with all possible pleiotropic traits included as covariates. However, the estimator obtained in this way will be inefficient if some of the covariates do not truly sit on pleiotropic pathways to the outcome. We present a method that uses regularization to identify which out of a set of potential covariates need to be accounted for in a Mendelian randomization analysis in order to produce an efficient and robust estimator of a causal effect. The method can be used in the case where individual-level data are not available and the analysis must rely on summary-level data only. It can be used where there are any number of potential pleiotropic covariates up to the number of genetic variants less one. We show the results of simulation studies that demonstrate the performance of the proposed regularization method in realistic settings. We also illustrate the method in an applied example which looks at the causal effect of urate plasma concentration on coronary heart disease.

The absolute risk of gout by clusters of gout-associated comorbidities and lifestyle factors-30 years follow-up of the Malmö Preventive Project

Background

Gout is predicted by a number of comorbidities and lifestyle factors. We aimed to identify discrete phenotype clusters of these factors in a Swedish population-based health survey. In these clusters, we calculated and compared the incidence and relative risk of gout.

Methods

Cluster analyses were performed to group variables with close proximity and to obtain homogenous clusters of individuals (n = 22,057) in the Malmö Preventive Project (MPP) cohort. Variables clustered included obesity, kidney dysfunction, diabetes mellitus (DM), hypertension, cardiovascular disease (CVD), dyslipidemia, pulmonary dysfunction (PD), smoking, and the use of diuretics. Incidence rates and hazard ratios (HRs) for gout, adjusted for age and sex, were computed for each cluster.

Results

Five clusters (C1–C5) were identified. Cluster C1 (n = 16,063) was characterized by few comorbidities. All participants in C2 (n = 750) had kidney dysfunction (100%), and none had CVD. In C3 (n = 528), 100% had CVD and most participants were smokers (74%). C4 (n = 3673) had the greatest fractions of obesity (34%) and dyslipidemia (74%). In C5 (n = 1043), proportions with DM (51%), hypertension (54%), and diuretics (52%) were highest. C1 was by far the most common in the population (73%), followed by C4 (17%). These two pathways included 86% of incident gout cases. The four smaller clusters (C2–C5) had higher incidence rates and a 2- to 3-fold increased risk for incident gout.

Conclusions

Five distinct clusters based on gout-related comorbidities and lifestyle factors were identified. Most incident gout cases occurred in the cluster of few comorbidities, and the four comorbidity pathways had overall a modest influence on the incidence of gout.

[Advantages of therapy with sodium glucose cotransporter type 2 inhibitors in patients with type 2 diabetes mellitus in combination with hyperuricemia and gout]

Currently, only two drugs for reducing uric acid (UA), allopurinol and febuxostat, are registered in the Russian Federation, but their use does not allow to achieve the target level of UA in all cases. According to the results of numerous randomized trials, hyperuricemia and gout are associated with the corresponding components of the metabolic syndrome, including diabetes mellitus. The influence of factors is due to the need to search for new drugs that have a complex effect on several components of metabolic syndrome at once. Potentially attractive in this regard is a new group of drugs for the treatment of type 2 diabetes mellitus inhibitors of the sodium-glucose cotransporter of type 2, which, in addition to the main hypoglycemic actions, showed positive effects on the cardiovascular system, kidneys, as well as lowering UA.

Serum uric acid and risk of incident diabetes in middle-aged and elderly Chinese adults: prospective cohort study

The association between serum uric acid and the risk of incident diabetes in Chinese adults remains unknown. This study aimed to investigate this association in a community-dwelling population aged ≥ 40 years in Shanghai, China. Oral glucose tole3rance test was conducted during baseline and follow-up visits. Relative risk regression was utilized to examine the associations between baseline gender-specific serum uric acid levels and incident diabetes risk. A total of 613 (10.3%) incident diabetes cases were identified during the follow-up visit after 4.5 years. Fasting plasma glucose, postload glucose, and glycated hemoglobin A1c during the follow-up visit progressively increased across the sex-specific quartiles of serum uric acid (all Ps < 0.05). The incidence rate of diabetes increased across the quartiles of serum uric acid (7.43%, 8.77%, 11.47%, and 13.43%). Multivariate adjusted regression analysis revealed that individuals in the highest quartile had 1.36-fold increased risk of diabetes compared with those in the lowest quartile of serum uric acid (odds ratio (95% confidence interval) = 1.36 (1.06-1.73)). Stratified analysis indicated that the association was only observed in women. Accordingly, serum uric acid was associated with the increased risk of incident diabetes among middle-aged and elderly Chinese women.

Guidelines for performing Mendelian randomization investigations

This paper provides guidelines for performing Mendelian randomization investigations. It is aimed at practitioners seeking to undertake analyses and write up their findings, and at journal editors and reviewers seeking to assess Mendelian randomization manuscripts. The guidelines are divided into nine sections: motivation and scope, data sources, choice of genetic variants, variant harmonization, primary analysis, supplementary and sensitivity analyses (one section on robust statistical methods and one on other approaches), data presentation, and interpretation. These guidelines will be updated based on feedback from the community and advances in the field. Updates will be made periodically as needed, and at least every 18 months.

Exploiting horizontal pleiotropy to search for causal pathways within a Mendelian randomization framework

In Mendelian randomization (MR) analysis, variants that exert horizontal pleiotropy are typically treated as a nuisance. However, they could be valuable in identifying alternative pathways to the traits under investigation. Here, we develop MR-TRYX, a framework that exploits horizontal pleiotropy to discover putative risk factors for disease. We begin by detecting outliers in a single exposure-outcome MR analysis, hypothesising they are due to horizontal pleiotropy. We search across hundreds of complete GWAS summary datasets to systematically identify other (candidate) traits that associate with the outliers. We develop a multi-trait pleiotropy model of the heterogeneity in the exposure-outcome analysis due to pathways through candidate traits. Through detailed investigation of several causal relationships, many pleiotropic pathways are uncovered with already established causal effects, validating the approach, but also alternative putative causal pathways. Adjustment for pleiotropic pathways reduces the heterogeneity across the analyses.

Asymptomatic hyperuricaemia: a silent activator of the innate immune system

Asymptomatic hyperuricaemia affects ~20% of the general population in the USA, with variable rates in other countries. Historically, asymptomatic hyperuricaemia was considered a benign laboratory finding with little clinical importance in the absence of gout or kidney stones. Yet, increasing evidence suggests that asymptomatic hyperuricaemia can predict the development of hypertension, obesity, diabetes mellitus and chronic kidney disease and might contribute to disease by stimulating inflammation. Although urate has been classically viewed as an antioxidant with beneficial effects, new data suggest that both crystalline and soluble urate activate various pro-inflammatory pathways. This Review summarizes what is known about the role of urate in the inflammatory response. Further research is needed to define the role of asymptomatic hyperuricaemia in these pro-inflammatory pathways.

Guidelines for performing Mendelian randomization investigations

This paper provides guidelines for performing Mendelian randomization investigations. It is aimed at practitioners seeking to undertake analyses and write up their findings, and at journal editors and reviewers seeking to assess Mendelian randomization manuscripts. The guidelines are divided into nine sections: motivation and scope, data sources, choice of genetic variants, variant harmonization, primary analysis, supplementary and sensitivity analyses (one section on robust methods and one on other approaches), data presentation, and interpretation. These guidelines will be updated based on feedback from the community and advances in the field. Updates will be made periodically as needed, and at least every 18 months.

Effects of hyperuricemia on incident renal replacement therapy and all-cause mortality among patients with chronic kidney disease stages 3-5: a retrospective cohort study

BACKGROUND

Findings regarding the effects of hyperuricemia on renal function and mortality have been inconsistent.

OBJECTIVES

To investigate the effects of hyperuricemia on incident renal replacement therapy and all-cause mortality among patients with chronic kidney disease (CKD).

DESIGN AND SETTING

Retrospective cohort study conducted in a medical center in Taiwan.

METHODS

Patients with CKD in stages 3-5, without histories of renal replacement therapy, were consecutively recruited from 2007 to 2013. Their medical history, laboratory and medication data were collected from hospital records. The mean uric acid level in the first year of follow-up was used for analyses. Hyperuricemia was defined as mean uric acid level ≥ 7.0 mg/dl in men or ≥ 6.0 mg/dl in women. The primary outcomes were incident renal replacement therapy and all-cause mortality, and these data were retrospectively collected from hospital records until the end of 2015.

RESULTS

A total of 4,381 patients were analyzed (mean age 71.0 ± 14.8 years; males 62.7%), and the median follow-up period was 2.5 years. Patients with hyperuricemia were at increased risk of incident renal replacement therapy and all-cause mortality, especially those with CKD in stages 4 or 5. Compared with patients with CKD in stage 3 and normouricemia, patients with CKD in stages 4 or 5 presented significantly higher risk of all-cause mortality only if they had hyperuricemia.

CONCLUSIONS

In patients with CKD in stages 3-5, hyperuricemia was associated with higher risk of incident renal replacement therapy and all-cause mortality. Whether treatment with uric acid-lowering drugs in these patients would improve their outcomes merits further investigation.

Genetically determined serum urate levels and cardiovascular and other diseases in UK Biobank cohort: A phenome-wide mendelian randomization study

BACKGROUND

The role of urate in cardiovascular diseases (CVDs) has been extensively investigated in observational studies; however, the extent of any causal effect remains unclear, making it difficult to evaluate its clinical relevance.

METHODS AND FINDINGS

A phenome-wide association study (PheWAS) together with a Bayesian analysis of tree-structured phenotypic model (TreeWAS) was performed to examine disease outcomes related to genetically determined serum urate levels in 339,256 unrelated White British individuals (54% female) in the UK Biobank who were aged 40-69 years (mean age, 56.87; SD, 7.99) when recruited from 2006 to 2010. Mendelian randomization (MR) analyses were performed to replicate significant findings using various genome-wide association study (GWAS) consortia data. Sensitivity analyses were conducted to examine possible pleiotropic effects on metabolic traits of the genetic variants used as instruments for urate. PheWAS analysis, examining the association with 1,431 disease outcomes, identified 13 distinct phecodes representing 4 disease groups (inflammatory polyarthropathies, hypertensive disease, circulatory disease, and metabolic disorders) and 9 disease outcomes (gout, gouty arthropathy, pyogenic arthritis, essential hypertension, coronary atherosclerosis, ischemic heart disease, chronic ischemic heart disease, myocardial infarction, and hypercholesterolemia) that were associated with genetically determined serum urate levels after multiple testing correction (p < 3.35 × 10-4). TreeWAS analysis, examining 10,750 ICD-10 diagnostic terms, identified more sub-phenotypes of cardiovascular and cerebrovascular diseases (e.g., angina pectoris, heart failure, cerebral infarction). MR analysis successfully replicated the association with gout, hypertension, heart diseases, and blood lipid levels but indicated the existence of genetic pleiotropy. Sensitivity analyses support an inference that pleiotropic effects of genetic variants on urate and metabolic traits contribute to the observational associations with CVDs. The main limitations of this study relate to possible bias from pleiotropic effects of the considered genetic variants and possible misclassification of cases for mild disease that did not require hospitalization.

CONCLUSION

In this study, high serum urate levels were found to be associated with increased risk of different types of cardiac events. The finding of genetic pleiotropy indicates the existence of common upstream pathological elements influencing both urate and metabolic traits, and this may suggest new opportunities and challenges for developing drugs targeting a common mediator that would be beneficial for both the treatment of gout and the prevention of cardiovascular comorbidities.

Target genes, variants, tissues and transcriptional pathways influencing human serum urate levels

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.

The association between hyperuricemia and coronary artery calcification development: A systematic review and meta-analysis

Hyperuricemia coincides with coronary artery calcification (CAC) development, but the role of serum uric acid (SUA) as a risk factor for CAC remains unclear. The objective of this study was to gain an insight into the association between SUA and CAC in adults by performing a meta-analysis. MEDLINE, EMBASE, the Cochrane Library, and EBSCO (CINAHL) were searched for relevant observational studies published until 2 June 2019. Studies were included only if they reported data on CAC presence (Agatston score > 0) or progression related to hyperuricemia in subclinical adult patients. The pooled estimates of crude and adjusted odds ratios (ORs) and 95% confidence interval (CI) were calculated to evaluate the association between CAC presence or progression and hyperuricemia. A total of 11 studies were identified involving 11 108 adults. The pooled OR based on the frequency of CAC presence showed that patients in the high SUA group had 1.806-fold risk for developing CAC (95% CI: 1.491-2.186) under the minimal threshold of hyperuricemia (more than 6 mg/dL or 357 μmoL/L). When SUA levels were analyzed as categorical variables, the pooled estimate of adjusted ORs was 1.48 (95% CI: 1.23-1.79) for CAC presence. Additionally, for each increase of 1 mg/dL of SUA level, the risk of CAC progression was increased by 31% (95% CI: 1.15-1.49) with an average follow-up duration ranged from 4.6 to 6.1 years. Hyperuricemia is closely associated with increased risk of CAC development and CAC progression in asymptomatic patients.