Hyperuricemia: A causal player or a bystander linking inflammatory signaling and atrial fibrillation?

Effect of hyperuricemia on paroxysmal atrial fibrillation after catheter ablation and influence of alcohol consumption

Background

Evidence regarding the association between hyperuricemia and arrhythmia recurrence after catheter ablation for paroxysmal atrial fibrillation (AF) is scarce. We investigated whether hyperuricemia predicts arrhythmia recurrence after catheter ablation for paroxysmal AF and the relationship between hyperuricemia and alcohol consumption in AF recurrence.

Methods

Patients who underwent catheter ablation for paroxysmal AF were divided into the hyperuricemia (index serum uric acid [UA] >7.0 mg/dL; n = 114) and control (UA ≤7.0 mg/dL; n = 609) groups and were followed for a median of 24 (12-48) months after ablation.

Results

The hyperuricemia group had more patients with an alcohol intake of ≥20 g/day (33.3% vs. 22.7%, p = .017) and a lower incidence of AF-free survival (p = .019). Similarly, those with an alcohol intake of ≥20 g/day had a lower incidence of AF-free survival than other patients. Multivariate Cox regression analysis revealed the following independent predictors of AF recurrence (adjusted hazard ratio, 95% confidence interval): hyperuricemia (1.64, 1.12-2.40), female gender (1.91, 1.36-2.67), brain natriuretic peptide level >100 pg/mL (1.59, 1.14-2.22), and alcohol consumption ≥20 g/day (1.49, 1.03-2.15) (all p < .05). In addition, causal mediation analysis revealed that alcohol consumption of ≥20 g/day directly affected AF recurrence, independent of hyperuricemia.

Conclusions

Patients with hyperuricemia may be at a high risk of arrhythmia recurrence after catheter ablation for paroxysmal AF. Although high alcohol consumption may contribute to increased UA levels, the presence of hyperuricemia may independently predict AF recurrence.

Update in uric acid, hypertension, and cardiovascular diseases

A direct relationship between serum uric acid levels and hypertension, cardiovascular, renal and metabolic diseases has been reported in many basic and epidemiological studies. Among these, high blood pression is one of the most common features associated with hyperuricemia. In this regard, several small-scale interventional studies have demonstrated a significant reduction in blood pressure in hypertensive or prehypertensive patients on uric acid-lowering drugs. These observation or intervention studies have led to affirm that there is a causal relationship between uric acid and hypertension. While the clinical association between uric acid and high blood pressure is notable, no clear conclusion has yet been reached as to whether lowering uric acid is beneficial to prevent cardiovascular and renal metabolic diseases. Recently, several prospective randomized controlled intervention trials using allopurinol and other uric acid-lowering drugs have been reported, and the results from these trials were almost negative, suggesting that the correlation between hyperuricemia and cardiovascular disease has no causality. However, it is important to note that in some of these recent studies there were high dropout rates and an important fraction of participants were not hyperuricemic. Therefore, we should carry caution in interpreting the results of these studies. This review article presents the results of recent clinical trials using uric acid-lowering drugs, focusing on hypertension and cardiovascular and renal metabolic diseases, and discusses the future of uric acid therapy.

Association between serum uric acid levels and atrial fibrillation in different fasting glucose patterns: A case-control study

BACKGROUND

Previous studies have shown both dysglycaemia and hyperuricemia are associated with an increased risk of atrial fibrillation (AF), while the relationship between serum uric acid (SUA) levels and AF in different fasting glucose patterns (FBG) is unclear. Therefore, this study aimed to determine the association between SUA and AF in different FBG patterns.

METHODS

A total of 1840 patients in this case-control study were enrolled, including 920 AF patients and 920 controls. Patients were divided into three groups according to the different FBG patterns: normoglycemic, impaired fasting glucose (IFG), and diabetes mellitus (DM). Multivariate logistic regression models were performed to evaluate the relationship between SUA and AF in different FBG patterns. Pearson correlation analysis was used to explore the correlation between SUA and metabolic factors. Receiver operating characteristic (ROC) curve models indicated the diagnostic efficiency of SUA for diagnosing AF.

RESULTS

SUA was independently associated with AF after adjusting for all confounding factors in different FBG patterns(normoglycemic: OR=1.313, 95% CI:1.120-1.539; IFG: OR=1.386, 95% CI:1.011-1.898; DM: OR=1.505, 95% CI:1.150-1.970). Pearson's correlation analysis suggested that SUA in AF patients was correlated with several different metabolic factors in different FBG patterns (p<0.05). ROC curve analysis showed that SUA in the normoglycemic group combined with CHD and APOB [AUC: 0.906 (95% CI: 0.888-0.923)], in the IFG group combined with CHD and Scr [AUC: 0.863 (95% CI: 0.820-0.907)], in the DM group combined with CHD and SBP [AUC: 0.858 (95% CI: 0.818-0.898)] had the highest AUC for predicting AF.

CONCLUSION

Findings implied a significant association between SUA and AF in different FBG patterns and provide specific models combined with other factors (CHD, APOB, SCr, SBP), which might contribute to the diagnosis of AF.

Increased Overall Heart Rate Irregularity Risk by Hyperuricemia in the General Population: Results from the Korean National Health and Nutrition Examination Survey

Background and objectives: Hyperuricemia is one of the well-known cardiovascular risk factors. There is a growing interest in the association between hyperuricemia and arrhythmia. We used the representative sample data of Korean population to study the association between hyperuricemia and heart rate irregularity (HRI) that reflects total arrhythmia. Materials and Methods: We performed weighted multivariate logistic regression analysis to assess the association between hyperuricemia and HRI. Results: Of the 10,827 subjects, 1308 (13.2%) had hyperuricemia and 130 (1%) had HRI. In the presence of hyperuricemia, HRI was three times higher than that in the absence of hyperuricemia (OR 2.98, 95% CI 1.71–5.18). The risk of HRI was highest in subjects with both hypertension and hyperuricemia. In the subgroup analysis, the association of hyperuricemia with HRI was most pronounced in the smoker group. Conclusions: Hyperuricemia was highly correlated with HRI in adult Korean representative sample data. Hyperuricemia was associated with a nearly tripled risk for HRI. Hypertension has a synergistic effect with hyperuricemia on HRI. Further research is warranted to clarify the relationship between hyperuricemia and arrhythmia and its mechanism.

Hyperuricemia is a Risk Factor for One-Year Overall Survival in Elderly Female Patients with Acute Coronary Syndrome

Background

Hyperuricemia is a risk factor for cardiovascular diseases, but the impact of hyperuricemia and sex-related disparities is not fully clear in elderly patients with acute coronary syndrome (ACS).

Objective

To investigate the association between hyperuricemia and 1-year all-cause mortality in elderly patients with ACS.

Methods

This retrospective cohort study included 711 consecutive ACS patients aged ≥75 years, hospitalized in our center between January 2013 and December 2017. Serum uric acid (sUA), in-hospital events, and 1-year follow-up were analyzed. Multivariable logistic regression models were used to explore the risk factors for in-hospital events and 1-year all-cause mortality.

Results

sUA levels were higher in males than in females (381.4 ± 110.1 vs. 349.3 ± 119.1 μmol/l, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%, P < 0.001). Prevalence of hypertension (80.5% vs. 72.6%,

Conclusions

Hyperuricemia is an independent risk factor for 1-year all-cause mortality in elderly female patients with ACS.

Gout and arrhythmias: In search for causation beyond association

Gout is a systemic disease, characterized by the formation and deposition of crystals in tissues (mainly in and around the joints) of individuals with elevated serum uric acid levels. Lately, a considerable number of reports relating elevated uric acid and/or gout with rhythm disorders, such as atrial fibrillation, have been published. This review summarizes evidence linking common arrhythmias and hyperuricemia/gout and discusses questions or controversies that surround it. Overall, existing evidence may not be overwhelming, but strongly suggests a positive correlation between uric acid levels and common rhythm disorders. Needless to say that such a link - as a univariate association between the two - is to be expected, given the extensive overlap of risk factors and comorbidities of hyperuricemia/gout and arrhythmias. However, the observed associations seem to persist - in most studies - after extensive adjustment for potential confounders. Still, multivariable analyses of epidemiologically collected data cannot substitute for proof coming from basic and clinical studies. There is obviously a need for further basic research to establish a causal relationship between uric acid effects and arrhythmias, as well as translational studies and clinical trials to investigate the therapeutic implications of such a relationship. Simply put, we are fairly certain that there is association, but proof of causation is what we are still in want of.

Hyperuricemia is associated with an increased prevalence of paroxysmal atrial fibrillation in patients with type 2 diabetes referred for clinically indicated 24-h Holter monitoring

PURPOSE

Several studies have reported an association between hyperuricemia and increased risk of permanent atrial fibrillation (AF) in patients with and without type 2 diabetes mellitus (T2DM). Currently, no published data are available on the relationship between hyperuricemia and risk of paroxysmal AF.

METHODS

We retrospectively evaluated 245 T2DM outpatients without pre-existing AF, cancer, cirrhosis and end-stage renal disease, who underwent a 24-h ECG-Holter monitoring for various clinical indications. Hyperuricemia was defined as a serum uric acid level >7 mg/dl for men and >6 mg/dl for women or allopurinol use. The diagnosis of paroxysmal AF was confirmed in affected individuals on the basis of 24-h ECG-Holter monitoring by experienced cardiologists.

RESULTS

Hyperuricemia was observed in 59 (24.1%) patients, whereas paroxysmal AF was found in 11 (4.5%) patients. The prevalence of paroxysmal AF was higher in patients with hyperuricemia than in those without hyperuricemia (10.2 vs. 2.7%, p = 0.026). Logistic regression analysis showed that hyperuricemia was associated with an increased risk of prevalent paroxysmal AF. This association remained significant even after adjustment for age, metabolic syndrome and chronic kidney disease (adjusted-odds ratio 4.01, 95% CI 1.08-14.9; p = 0.039). Similar results were found when we used serum uric acid levels as a continuous measure.

CONCLUSIONS

This study shows for the first time that hyperuricemia is independently associated with an approximately fourfold increased risk of prevalent paroxysmal AF in patients with T2DM. These findings may partly explain the increased risk of permanent atrial fibrillation and cardiovascular death observed among patients with hyperuricemia.