Impact Of Serum Uric Acid Levels Research Articles

The Prognostic Impact of Serum Uric Acid on Disease Severity and 5-Year Mortality in Patients With Idiopathic Pulmonary Artery Hypertension.

BackgroundSerum uric acid (UA) has long been identified as a prognostic factor of adverse outcomes in pulmonary hypertension. However, there remains a paucity of evidence on patients with idiopathic pulmonary artery hypertension (IPAH) in the era of targeted drug therapy. This study aims to explore the impact of serum UA levels on the disease severity and mortality in patients with IPAH.MethodsConsecutive patients diagnosed with IPAH were enrolled, from which UA levels at baseline and the first follow-up were collected. Patients were divided into groups of “hyperuricemia,” which is defined as serum UA level ≥357 μmol/L in women and ≥420 μmol/L in men, and otherwise “normouricemia.” The potential relationship between UA and hemodynamics at right heart catheterization was investigated. Associations between UA and survival were evaluated by Kaplan-Meier analysis and Cox proportional hazard modeling.ResultsOf 207 patients with IPAH, 121 (58.5%) had hyperuricemia. Higher serum UA levels were associated with lower cardiac index (r = 0.47, p < 0.001) and higher pulmonary vascular resistance (r = 0.36, p < 0.001). During a median follow-up of 34 months, there were 32 deaths recorded, accounting for a 15.5% mortality rate. Patients with hyperuricemia had a significantly lower survival rate than those with normouricemia (log-rank test, p = 0.002). Hyperuricemia at baseline was independently associated with a 2.6-fold increased risk of 5-year death, which was consistent across different subgroups, especially in females and those aged ≥30 years (each p < 0.05). Individuals with higher variability in UA had a higher mortality than those with stable UA (log-rank test, p = 0.024).ConclusionsBaseline hyperuricemia and high variability in serum UA at first follow-up were related to a higher rate of 5-year mortality in patients with IPAH. Closely detecting the UA levels may aid in the early recognition of IPAH patients at higher mortality risk.

Gender differences in the impact of plasma xanthine oxidoreductase activity on coronary artery spasm

Abstract Background It has been reported that decreased nitric oxide bioavailability due to increased reactive oxygen species (ROS) is one of the most important causes of coronary artery spasm (CAS). Xanthine oxidoreductase (XOR) is the rate-limiting enzyme for uric acid (UA) production and plays a pivotal role in generating ROS. It was reported that the gender differences exist in the impact of serum UA levels on cardiovascular risks. We previously demonstrated that increased plasma XOR activity is significantly associated with the incidence of CAS. However, the gender differences in the impact of plasma XOR activity on CAS remain unclear. Purpose The aim of this study was to examine the gender differences in the clinical impact of plasma XOR activity on CAS. Methods We investigated plasma XOR activity in 132 patients suspected for CAS (male, n=78; female, n=54), and underwent intracoronary acetylcholine provocation test. XOR activity assay was performed using stable isotope-labeled substrate and liquid chromatography-triple quadrupole mass spectrometry. Provoked CAS was defined as total or subtotal occlusion (≥90%) with accompanying symptoms of chest pain and/or ischemic ST-segment changes on the electrocardiogram. We excluded the patients who had significant coronary artery stenosis (≥50%) and/or were taking XOR inhibitors. Results Plasma XOR activity was significantly lower in female compared with male patients (30.3 pmol/h/mL, interquartile range (IQR) 22.8–42.7 vs. 51.7 pmol/h/mL, IQR 34.7–101.8; P&amp;lt;0.001). CAS was provoked in 36 male patients and 17 female patients, and they each had significantly higher plasma XOR activity compared with those without, respectively. Multivariate logistic regression analysis showed that plasma XOR activity was independently associated with the incidence of CAS in both genders after adjustment for confounding factors. The optimal cut-off values for predicting CAS were lower in female than those in male patients (52.3 vs. 91.6 pmol/h/mL). Multivariate analysis demonstrated that female patients with high XOR activity (≥52.3 pmol/h/mL; odds ratio [OR] 22.6, P&amp;lt;0.001) exhibited a higher incidence of CAS compared with that in male patients (≥91.6 pmol/h/mL; OR 8.2, P&amp;lt;0.001). Conclusions Plasma XOR activity was an independent predictor for the incidence of CAS in both genders. The impact of plasma XOR activity on CAS was stronger in female patients than in male patients. Funding Acknowledgement Type of funding sources: None. Figure 1Figure 2

Serum uric acid levels and the risk of recurrent venous thromboembolism

Unlabelled Box AbstractBackgroundThe link between serum uric acid (SUA) and the risk of cardiovascular disease is well established. However, the impact of SUA levels on the risk of venous thromboembolism (VTE) recurrence is unknown. ObjectivesTo investigate the association between SUA and the risk of VTE recurrence. Patients and MethodsWe performed a monocenter, prospective study on 280 patients with a previous episode of VTE that completed the oral anticoagulant period. SUA levels at enrollment were correlated with the risk of VTE recurrence (mean follow‐up 71.1 ± 29.2 months). ResultsPatients were stratified according to SUA tertiles distribution at baseline (tertiles cut‐off: I ≤ 4.37 mg/dL, II 4.38‐‐5.54 mg/dL, III ≥ 5.55 mg/dL). Fifty episodes of VTE recurrence occurred during the follow‐up and Kaplan‐Meier survival analysis showed that subjects in the lower tertile of SUA distribution had significantly lower risk of future VTE recurrence (P = .003). No differences were seen among patients belonging to the second and the third tertile of SUA distribution. A multivariate Cox regression analysis showed that higher tertiles of SUA distribution had about three‐fold increase in the risk of VTE recurrence as compared to subjects with SUA ≤ 4.37, independently from potential confounders (hazard ratio [HR] 3.04, 95% confidence interval [CI] 1.15‐‐8.05 P = .025). Moreover, we observed that the adjusted hazard of VTE recurrence increased by 30% for each additional unit of SUA (mg/dL; HR 1.30, 95% CI 1.01‐‐1.22, P = .040). ConclusionElevated SUA levels are associated with increased risk of future VTE recurrence independently from traditional risk factors.

THE INFLUENCE OF URIC ACID LEVEL ON ERYTHROCYTE MORPHOLOGY IN NORMOTENSIVE PATIENTS

Introduction: Hyperuricemia is an independent risk factor for high-normal blood pressure (BP) both in men and women. The effect of uric acid (UA) on erythrocyte morphology in normotensive patients needs further study. The aim - to evaluate the impact of serum UA level on erythrocyte morphology in normotensive patients. Materials and methods: Patients were divided into two group according to the UA level: the first group - 38 patients with UA level < 400 mcmol/L; the second group - 42 patients with UA level ≥ 400 mcmol/L. Studies on erythrocyte morphology were conducted using cytological analysis and scanning electron microscopy. Results: Patients of the 1st group had poikilocytosis level of 4,6%, while type I echinocytes were 3,2%, type II echinocytes - 1,1%, stomatocytes - 1,3%. In the 2nd group, poikilocytosis exceeding 5% was observed in 12 patients with mean values of altered shapes of 12,8±1,2%. In the 2nd group, type I echinocytes was 6,2% (9,4±0,9%) more, type II echinocytes - 1,3% (2,4±0,5%) more, stomatocytes - 0,3% (1,0±0,2%) more. In the study correlation between UA and poikilocytosis was found: in the 1st group - r = +0,21 and in the second group - r = +0,42. In the 1st group, correlation between UA and BP was moderate for SBP - r = +0,34 and weak for DBP - r = +0,29; in the 2nd group: SBP - r = +0,49 and r = +0,35 for DBP. Conclusions: Direct correlation between uric acid level and poikilocytosis level becomes more intensive when uric acid level exceeds ≥ 400 mcmol/L.

The impact of serum uric acid on the natural history of glomerular filtration rate: a retrospective study in the general population.

Serum uric acid (SUA) level has been proposed to have important connections with chronic kidney disease (CKD), while the impact of SUA level on the natural history of glomerular filtration rate (GFR) decline remains unknown. The present study aims to study the association of the SUA level with the GFR decline in a general population. Two thousand, seven hundred and eighty-nine subjects who visited the Health Checkup Clinic both at 2008 and 2013 were identified. A significant inverse correlation was observed between change in SUA from 2008–2013 (ΔSUA) and change in eGFR (ΔeGFR) during the same period. Multivariate regression analysis of ΔeGFR indicated that the increase in SUA over time were a negative predictor of the change in eGFR. Our result indicates that the decline of eGFR over years is larger in subjects with an increased SUA level, which helps to underline the importance of SUA level management in the context of kidney function preservation.

The impact of serum uric acid level to CSFP

Objective To investigate on the impact of the serum uric acid (UA) level coronary slow flow phenomenon(CSFP).Methods Selected 30 cases of coronary slow flow patients as CSFP group,30 cases of patients with coronary heart disease,30 cases of patients with angiographically normal as the control group.The serum UA level was measured in three groups.The CSFP group and the control group were measured left anterior descending,circumflex and right coronary artery TIMI frame count(TFC) value.To analyze the mean TFC value of CSFP patients and the relationship between the serum UA level.Results Compared with the control group,the left anterior descending,circumflex and right coronary TFC results were significantly higher(all P ＜ 0.05) in the CSFP group.The mean serum UA level of CSFP group ,control group and CHD group were(340.79 ± 79.40)μmol/L, (220.45 ± 82.34)μmol/L,(42625 ± 87.02) μmol/L, the difference was statistically significant (all P ＜ 0.05).The mean serum UA level and TFC value of CSFP group was positively correlated(r = 0.943, P = 0.007).Conclusion Elevated level of serum UA is closely related to the occurrence and development of the CSFP. Key words: Coronary slow flow phenomenon; Uric acid; Angiography