Predictors of stroke mortality in elderly people from the general population. The CArdiovascular STudy in the ELderly

Asymptomatic hyperuricemia: to treat or not a threat? A clinical and evidence-based approach to the management of hyperuricemia in the context of cardiovascular diseases

Asymptomatic hyperuricemia is defined by serum uric acid levels above 6.2 mg/dl in women and 7 mg/dl in men. In the presence of monosodium urate crystal formation and articular inflammation, hyperuricemia may become symptomatic (namely nephrolithiasis and gout). Uric acid results from purine catabolism and is at the centre of a complex metabolic interplay that involves oxidative stress, inflammation, renin-angiotensin-aldosterone system (RAAS) activation and insulin resistance. Uric acid levels present a continuous relation with conditions like hypertension and chronic kidney disease (CKD) and are reported to have an impact on risk of cardiovascular events. However, whether elevated uric acid is a causal agent and thus a possible therapeutic target is still uncertain and matter of further investigation. Treating symptomatic hyperuricemia involves lowering uric acid drugs and controlling inflammation. Urate-lowering agents are well tolerated but show minimal impact on cardiovascular events in patients with gout. Use of direct-acting urate-lowering agents in asymptomatic hyperuricemia associated with cardiovascular diseases does not warrant a clear benefit, whereas addressing cardiovascular issues with guideline-recommended therapies lowers uric acid and reduces the occurrence of cardiovascular events. Regular assessment of uric acid and clinical symptoms is advised before starting and renewing a urate-lowering treatment.

The combination of high uric acid and high C-reactive protein increased the risk of cardiovascular disease: A 15-year prospective cohort study

BACKGROUND AND AIMS

Uric acid (UA) and C-reactive protein (CRP) may interact synergistically to accelerate the initiation and progression of cardiovascular disease (CVD). This study investigated the effects of a combination of high UA and high CRP on the risks of CVD.

METHODS AND RESULTS

A total of 90,270 participants recruited from the Kailuan study were included, who were divided into four groups according to the presence/absence of hyperuricemia and inflammation. Cox regression was applied to evaluate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) of CVD. C-statistics, net classification index (NRI), and integrated discrimination improvement (IDI) were used to compare the incremental predictive of UA, CRP, and their combined effects on CVD. Mediation analysis was to explore the impact of CRP on the association between UA and CVD. Over a median follow-up of 14.95 years, we identified 11398 incident CVD cases. Compared to the low UA/low CRP group, the high UA/low CRP, low UA/high CRP and high UA/high CRP groups showed progressively higher risks of CVD, HR (95% CI): 1.18(1.10-1.27), 1.27(1.21-1.33) and 1.50 (1.33-1.69), respectively. The incorporation of UA and CRP into the traditional China-PAR model led to improvement in the C-statistic, NRI, and IDI, and was better than incorporation of either UA or CRP alone. Mediation analysis showed that CRP mediated the association between UA and CVD, accounting for 11.57% of the total effects.

CONCLUSIONS

High UA/high CRP is associated with increased risks of CVD. Incorporation of both UA and CRP provided additional value for risk stratification.

Potassium status and the risk of type 2 diabetes, cardiovascular diseases, and mortality: a meta-analysis of prospective observational studies

Epidemiological evidence on the association between potassium and cardiometabolic outcomes remains controversial. This study aimed to examine associations of dietary intake and blood and urinary levels of potassium with risk of type 2 diabetes, cardiovascular disease (CVD), and mortality. Relevant prospective studies were retrieved through a comprehensive search of four electronic databases up to July 1, 2023. Random-effects models were used to pool the study-specific relative risks (RRs) and 95% confidence intervals (CIs). Fifty-six studies were included in this meta-analysis. A higher intake of potassium was significantly associated with a 16% lower risk of CVD (RR: 0.84, 95% CI: 0.78-0.90). Similar inverse associations were also observed between potassium intake and mortality. Each 1.0 g/d increment in potassium intake was associated with a decreased risk of CVD (RR: 0.85, 95% CI: 0.80-0.91) and all-cause mortality (RR: 0.93, 95% CI: 0.88-0.99). For blood and urinary potassium levels, higher level of blood potassium increased the risk of all-cause mortality by 23% (RR: 1.23, 95% CI: 1.11-1.36). The association of blood potassium levels with mortality was nonlinear (Pnon-linearit<0.001). However, urinary potassium levels were inversely associated with the risk of all-cause mortality (RR: 0.84, 95% CI: 0.76-0.93). Our findings support the benefits of moderate potassium consumption for primary prevention of chronic diseases and premature death.

Stroke Risk in Patients with Gout: A Nationwide Retrospective Cohort Study in Taiwan

Objectives: To estimate stroke risk in Taiwanese patients with gout. Methods: We enrolled patients from the Taiwan National Health Insurance Database, with gout diagnosed from 2000 to 2008, and followed them up until December 2018. This cohort was propensity score-matched according to birth year, sex, the date of diagnosis of gout, comorbidities, and co-medications with individuals without gout (controls) (n = 310,820 in each group). Stroke was defined as the primary diagnosis at discharge after the index date. To evaluate ischemic and hemorrhagic stroke risks, we calculated their incidence, hazard ratio (HR), and two-year moving average incidence rate. Results: The incidence (95% CI) and HR of ischemic stroke were lower in the gout group than in the control group in the first 3 years (incidence: 4.74 [4.60–4.88] vs. 5.17 [5.03–5.32] per 1000 person-years; HR: 0.92 [0.88–0.96]), then became significantly higher than in the control group after 3 years (incidence: 4.10 [4.04–4.16] vs. 3.81 [3.75–3.87] per 1000 person-years; HR: 1.08 [1.05–1.10]). Similarly, the incidence (95% CI) and HR of hemorrhagic stroke was lower in the gout group than in the control group in the first 3 years (incidence: 1.51 [1.43–1.59] vs. 1.70 [1.62–1.79] per 1000 person-years; HR: 0.88 [0.82–0.92]), then became significantly higher than in controls after 3 years (incidence: 1.43 [1.39–1.46] vs. 1.26 [1.22–1.29] per 1000 person-years; HR: 1.14 [1.10–1.18]). Conclusions: In Taiwan, patients with gout had higher risks of ischemic and hemorrhagic stroke after 3 years.

Mitochondrial Oxidative Stress-A Causative Factor and Therapeutic Target in Many Diseases

The excessive formation of reactive oxygen species (ROS) and impairment of defensive antioxidant systems leads to a condition known as oxidative stress. The main source of free radicals responsible for oxidative stress is mitochondrial respiration. The deleterious effects of ROS on cellular biomolecules, including DNA, is a well-known phenomenon that can disrupt mitochondrial function and contribute to cellular damage and death, and the subsequent development of various disease processes. In this review, we summarize the most important findings that implicated mitochondrial oxidative stress in a wide variety of pathologies from Alzheimer disease (AD) to autoimmune type 1 diabetes. This review also discusses attempts to affect oxidative stress as a therapeutic avenue.

Impact of prior cerebrovascular disease and glucose status on incident cerebrovascular disease in Japanese

BACKGROUND

Although both a history of cerebrovascular disease (CVD) and glucose abnormality are risk factors for CVD, few large studies have examined their association with subsequent CVD in the same cohort. Thus, we compared the impact of prior CVD, glucose status, and their combinations on subsequent CVD using real-world data.

METHODS

This is a retrospective cohort study including 363,627 men aged 18-72 years followed for ≥ 3 years between 2008 and 2016. Participants were classified as normoglycemia, borderline glycemia, or diabetes defined by fasting plasma glucose, HbA1c, and antidiabetic drug prescription. Prior and subsequent CVD (i.e. ischemic stroke, transient ischemic attack, and non-traumatic intracerebral hemorrhage) were identified according to claims using ICD-10 codes, medical procedures, and questionnaires.

RESULTS

Participants' mean age was 46.1 ± 9.3, and median follow up was 5.2 (4.2, 6.7) years. Cox regression analysis showed that prior CVD + conferred excess risk for CVD regardless of glucose status (normoglycemia: hazard ratio (HR), 8.77; 95% CI 6.96-11.05; borderline glycemia: HR, 7.40, 95% CI 5.97-9.17; diabetes: HR, 5.73, 95% CI 4.52-7.25). Compared with normoglycemia, borderline glycemia did not influence risk of CVD, whereas diabetes affected subsequent CVD in those with CVD- (HR, 1.50, 95% CI 1.34-1.68). In CVD-/diabetes, age, current smoking, systolic blood pressure, high-density lipoprotein cholesterol, and HbA1c were associated with risk of CVD, but only systolic blood pressure was related to CVD risk in CVD + /diabetes.

CONCLUSIONS

Prior CVD had a greater impact on the risk of CVD than glucose tolerance and glycemic control. In participants with diabetes and prior CVD, systolic blood pressure was a stronger risk factor than HbA1c. Individualized treatment strategies should consider glucose tolerance status and prior CVD.

Association Between Vitamin D and Hyperuricemia Among Adults in the United States

Background: Serum uric acid can act as a risk factor for cardiovascular disease (CVD) and as antioxidant defense. Vitamin D deficiency can activate the parathyroid to induce the release of parathyroid hormone, which was thought to increase serum uric acid level, and low vitamin D status may also be associated with risk of CVD. No known studies have explored the association between serum 25(OH) D, vitamin D intake, and HU for the American population.

Methods: We extracted 15,723 US adults aged 20–85 years from the National Health and Nutrition Examination Survey (NHANES) in 2007–2014. All dietary intakes were evaluated through 24-h dietary recalls. Multivariable logistic regression analysis was performed to examine the associations after adjustment for confounders.

Results: Compared to the lowest quintile (Q1), for males, adjusted odds ratios (ORs) of HU in Q2 to Q4 of serum 25(OH) D levels were 0.78 (95% CI, 0.65–0.93), 0.97 (0.81–1.16), and 0.72 (0.60–0.88); ORs in Q2–Q5 of total vitamin D intake were 0.83 (0.69–0.98), 0.69 (0.58–0.83), 0.66 (0.55–0.79), and 0.59 (0.48–0.71), respectively. In females, OR was 0.80 (0.66–0.97) of serum 25(OH) D for Q3, and ORs in Q5 of total vitamin D intake were 0.80 (0.65–0.98).

Conclusions: Our findings indicated that the serum 25(OH) D intakes of dietary vitamin D, supplemental vitamin D, and total vitamin D were inversely associated with HU in males. In females, a lower risk of HU with higher serum 25(OH) D, dietary vitamin D, and total vitamin D intake was found, but with no association between supplemental vitamin D intake and the risk of HU.

Higher uric acid is associated with better discharge recovery and short-term outcome in stroke patients treated with thrombolysis

BACKGROUND

Uric acid (UA) possesses antioxidant features and potential neuroprotective effects. However, conflicting results regarding the association between serum uric acid (SUA) levels and the prognosis of stroke have been obtained. We aimed to assess whether SUA is related to discharge recovery and short-term outcomes in patients who underwent thrombolysis therapy.

METHODS

We recruited 393 consecutive patients who were diagnosed with acute ischaemic stroke (AIS) and treated with thrombolysis. The demographic information, including sex and age, was collected. Haematology tests, including SUA, fasting plasma glucose (FPG), and blood lipid parameters, were performed under fasting conditions the morning after admission. The modified Rankin Scale (mRS) was used to assess the functional outcome of patients at discharge and 3 months after onset.

RESULTS

A negative correlation was observed between the levels of SUA and the National Institute of Health Stroke Scale (NIHSS) score at discharge (r = - 0.171, P = 0.003). Additionally, a positive correlation was observed between the levels of SUA and the difference between the baseline NIHSS and discharge NIHSS (r = 0.118, P = 0.032). The levels of SUA in the patients with good outcomes (353.76 ± 93.05) were higher than those in the patients with poor outcomes (301.99 ± 92.24; P = 0.015) at 3 months. The multivariate logistic regression analysis demonstrated that a higher SUA level (odds ratio 0.988, 95% confidence interval 0.985-0.991, P = 0.002) was an independent predictor of a good outcome at 3 months.

CONCLUSION

Higher SUA levels were associated with better discharge recovery and 3-month outcomes in patients with ischaemic stroke who received thrombolysis.

Hyperuricemia is associated with metabolic syndrome in the community very elderly in Chengdu

Hyperuricemia is a risk factor for cardiovascular metabolic diseases. However, in the very elderly, the relationship between hyperuricemia and the metabolic syndrome (MetS) is not yet clear. This study was aimed to investigate the potential association between hyperuricemia and MetS in community very elderly in Chengdu. In this cross-sectional study, 1056 very elderly in the community were enrolled. Serum uric acid (SUA), fast plasma glucose, triglycerides and high–density lipoprotein cholesterol were measured, and then MetS components were calculated. Logistic regression models were used to explore risk factors for MetS in the very elderly. Finally, 1035 participants were included in analysis whose ages ranged between 80 and 100 with a mean age of 83.6 ± 3.4 years. The mean SUA level was 356.2 ± 95.0 µmol/L. The estimated prevalence of MetS in the very elderly was 25.0% vs. 21.6% (international diabetes federation (IDF) criteria vs. Chinese guideline), which was significantly higher for women (IDF criteria:17.3% in men vs 33.6% in women, p < 0.001). Logistic regression has found that participants with hyperuricemia (SUA level > 416 µmol/L in men and > 357 µmol/L in women) had a higher risk (IDF criteria: odds ratio (OR): 2.136, 95% confidence interval(CI): 1.525–2.993, p < 0.001. Chinese guideline: OR: 1.769, 95%CI: 1.249–2.503, p = 0.001) of MetS in very elderly Chinese. MetS is common in the community of very elderly Chinese in Chengdu. Hyperuricemia is associated with MetS in general very elderly and lifestyle changing should also be considered in the very elderly.

The differential role of uric acid - The purpose or cause of cardiovascular diseases?

For 40 years many studies have been conducted to verify the connection between serum uric acid concentration and cardiovascular diseases, such as myocardial infarction. Unfortunately, it remains unclear which form of uric acid - prooxidant or antioxidant - could be a predictive marker of cardiovascular disease, especially in patients after myocardial infarction. It is well-known that uric acid is an organic compound and the water-soluble final product of purine catabolism, which is catalysed by xanthine oxidoreductase and excreted by kidneys. An increased concentration of UA in human plasma leads to diseases like tumours, renal disorders, atherosclerosis, hypertension, diabetes, metabolic syndrome, polycythaemia vera, haemolytic anaemias, ischemia, oxidative stress, and rare genetic disorders connected with UA degradation. Epidemiological studies have shown that UA might be a marker of oxidative stress, progression of inflammation, or renal disease. A fortiori, it is possible that could also be a predictor for short/long-term survival of patients with CVD. Evidence provided by multiple studies is controversial and mutually exclusive. Among 71 studies the most of them found an independent association between SUA and CVD risk. Some of those studies confirm that CVD risk is higher in women who had elevated SUA levels. On the other hand, many studies reached the opposite conclusion and did not find any relationship between SUA and CVD mortality and morbidity.

Stress hyperglycemia and electrolytes disturbance in patients with acute cerebrovascular stroke

Background

Stroke is a medical emergency and considered the 2nd leading cause of mortality worldwide. High morbidity and mortality of stroke are due to some complications like cerebral edema, infection, and associated heart disease. Stroke may cause stress hyperglycemia and electrolyte disturbance that may be independent predictors for increased morbidity and mortality. Data on electrolyte disorder in neurological conditions especially acute stroke are somewhat scanty and not frequently interpreted.

Objectives

The current study aimed to evaluate the effect of stress induced by acute stroke on the blood glucose and serum electrolytes and its relationship to the type, severity, and prognosis of stroke.

Subjects and methods

A total of 100 patients admitted with acute stroke were included in the study. After informed consent, fasting blood sugar, glycosylated hemoglobin, serum sodium, and potassium levels were measured simultaneously. Stroke severity and outcome were assessed using the Glasgow Coma Scale.

Results

Stress hyperglycemia was noted in 21 patients, out of which 62% presented with hemorrhagic stroke. Undiagnosed diabetes was found in 47% of cases. Also, 13 % of our patients had both stress hyperglycemia and electrolyte disturbance simultaneously. Mortality among hemorrhagic versus ischemic patients was 46% and 22%, respectively. The independent predictors of mortality were stress hyperglycemia, electrolytes disturbance, ischemic heart diseases, and type and admission severity of stroke.

Conclusion

Stress hyperglycemia and electrolyte disturbance after acute stroke were found in 21% and 47% of patients respectively and may adversely affect outcome of stroke especially those with cerebral hemorrhage.

Hypertension in a resource-limited setting: Poor Outcomes on Short-term Follow-up in an Urban Hospital in Maputo, Mozambique

Mozambique has low levels of detection, treatment, and control of hypertension. However, data on target organ damage and clinical outcomes are lacking. The authors aimed at characterizing the clinical profile, pattern of target organ damage, and short-term outcomes of patients referred to a first referral urban hospital in a low-income setting in Africa. We conducted a prospective descriptive cohort study from February 2016 to May 2017 in Maputo, Mozambique. Adult patients with systolic and diastolic blood pressure ≥180 mm Hg and/or ≥110 mm Hg, respectively, or any systolic blood pressure above 140 mm Hg and/or diastolic blood pressure above 90 mm Hg in the presence of target organ damage (with or without antihypertensive treatment) were submitted to detailed physical examination, funduscopy, laboratory profile, electrocardiography, and echocardiography. Six months after the occurrence of complications (stroke, heart failure, and renal failure), hospital admission and death were assessed. Overall, 116 hypertensive patients were recruited (mean age 57.5 ± 12.8 years old; 111[95.7%] black; 81[70%] female) of which 79 had severe hypertension. The baseline mean values recorded for systolic and diastolic blood pressure were 192.3 ± 23.6 and 104.2 ± 15.2 mm Hg, respectively. Most patients (93; 80.2%) were on antihypertensive treatment. Patients' risk profile revealed dyslipidemia, obesity, and diabetes in 59(54.1%), 48(42.5%), and 23(19.8%), respectively. Target organ damage was found in 111 patients. The commonest being left atrial enlargement 91(84.5%), left ventricular hypertrophy 57(50.4%), hypertensive retinopathy 30(26.3%), and chronic kidney disease 27(23.3%). Major events during 6-month follow-up were hospitalizations in 10.3% and death in 8.6% of the patients. Worsening of target organ damage occurred in 10 patients: four stroke, two heart failure, and four renal damage. Patients with severe hypertension and target organ damage were young with high-risk profile, low hypertension control, and high occurrence of complications during short-term follow-up. Efforts to improve high blood pressure control are needed to reduce premature mortality in this highly endemic poor setting.

Association between serum uric acid and large-nerve fiber dysfunction in type 2 diabetes: a cross-sectional study

Background

Large-nerve fiber dysfunction, as assessed by vibration perception threshold (VPT) predicts risks of ulceration, amputation, and mortality in diabetes. Serum uric acid (UA) is closely associated with various metabolic disorders, especially diabetes. Thus, we sought to investigate the clinical relevance of UA to large-nerve fiber dysfunction, among patients with type 2 diabetes (T2D).

Methods

Medical records of consecutive patients with T2D who were admitted to Beijing Friendship Hospital Pinggu Campus between May 2014 and December 2016 were collected. Data for the 824 eligible patients included in the final analysis were extracted using a structured form. A VPT value ≥15 in either foot was defined as abnormal. We compared the clinical characteristics between patients with abnormal VPT and those with normal VPT (VPT value <15 in both feet) in the overall population and in gender subgroups. Logistic regression analysis was performed to explore the association of abnormal VPT with UA level. One-way analysis of variance was used to compare VPT values across four UA quartiles.

Results

UA levels were significantly lower in T2D patients with abnormal VPT than in those with normal VPT (294.5 ± 84.0 vs. 314.9 ± 92.8 μmol/L, P < 0.01), especially among male patients (311.7 ± 85.2 vs. 336.9 ± 89.6 μmol/L, P < 0.01). From the logistic regression analysis, hyperuricemia (males >420 μmol/L; females >360 μmol/L) was associated with a reduced risk of abnormal VPT (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.39–0.91; P < 0.05). This association was robust in male patients (OR, 0.43; 95% CI, 0.24–0.76; P < 0.01) but not in female patients (OR, 0.92; 95% CI, 0.47–1.82; P = 0.816), even after adjustment for confounding factors. For the younger male subgroup (age <65 years), VPT values decreased as the UA level increased (P for trend = 0.002), but this trend was not significant in older male subgroup (age ≥65 years; P for trend = 0.400).

Conclusions

Low serum UA levels showed a significant association with an increased risk of large-nerve fiber dysfunction in male patients with T2D, but not in female patients with T2D. In addition, in only the younger subgroup of male patients (<65 years), lower levels of UA also correlated with higher VPT values.

Associations of serum uric acid with total and cause-specific mortality: Findings from individuals and pooling prospective studies

BACKGROUND AND AIMS

There is considerable controversy regarding the link between serum uric acid (SUA) and mortality. We prospectively evaluated the association between SUA and risk of total and cause specific (coronary heart disease [CHD], cerebrovascular and cancer) mortality by using the National Health and Nutrition Examination Surveys (NHANES, 1999-2010). Furthermore, a systematic review and meta-analysis of cohort studies was performed to investigate pooled associations of SUA with all-cause and cause-specific mortality.

METHODS

Vital status through December 31, 2011 was ascertained. PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched (up to April 2018). Adjusted Cox proportional hazard regression models were used to determine the association between SUA and mortality. The DerSimonian-Laird method and generic inverse variance methods were used for quantitative data synthesis.

RESULTS

Overall, 21,025 individuals were included (mean age = 47.6 years, 48.7% men) and 3520 deaths occurred during the 144 months of follow-up. In adjusted models, individuals in the highest quartile of SUA had 10 and 8% greater risk of CHD and stroke mortality, whereas there was no link between SUA, all-cause and cancer mortality. The associations of CHD and stroke mortality with SUA were more pronounced in women and, among women, in those aged >50 years. Furthermore, all-cause mortality was positively and significantly related to SUA concentrations only in women. In the meta-analysis, SUA was shown to predict the risk of total (21%), CHD (24%) and stroke (29%) mortality. Furthermore, participants with a higher level of central adiposity had a greater risk of mortality from CHD and stroke for the same level of SUA.

CONCLUSIONS

Our results highlight the adverse impact of SUA on mortality, particularity in older (>50 years) women. The clinical implications of these findings remain to be established in future trials.

Hyperuricemia is associated with atrial fibrillation prevalence in very elderly - a community based study in Chengdu, China

Hyperuricemia is a risk factor for cardiovascular diseases. However, in very elderly, the relationship between hyperuricemia and the prevalence of atrial fibrillation (AF) is not clear. This study aimed to investigate hyperuricemia and the risk of AF in community very elderly. In this cross-sectional study, 1056 very elderly in community were enrolled. Serum uric acid (SUA) were measured and rest 12-lead electrocardiogram was performed. Multiple logistic regression models were used to explore risk factors for AF in very elderly. Finally, 1038 participants were included in analysis and the mean age of the study participants were 83.6 ± 3.4 years (age range 80–100 years). The mean SUA level was 350.1 ± 84.5 µmol/L. The estimated prevalence of AF was 5.3%, and there was no significant sex difference (5.8% for men and 4.8% for women, p = 0.401). Multiple logistic regression found that participants with hyperuricemia (SUA >416 µmol/L in men and >357 µmol/L in women) had a higher risk (odds ratio: 2.080, 95% confidence interval: 1.103–4.202, P = 0.007) of suffering AF in very elderly Chinese. In conclusion, AF is relatively frequent in this community very elderly Chinese in Chengdu. Hyperuricemia is associated with the prevalence of AF in general very elderly.

CHA2DS2-VASc score as a predictor of long-term cardiac outcomes in elderly patients with or without atrial fibrillation

BACKGROUND

The CHA2DS2-VASc score is often used for stroke risk stratification in atrial fibrillation (AF) patients. However, its usefulness in patients ≥75 years of age with or without AF is unclear.

OBJECTIVE

We aimed to investigate whether the CHA2DS2-VASc score can predict ischemic stroke (IS), transient ischemic attack, thromboembolism (TE), and mortality in elderly patients with and without AF.

MATERIALS AND METHODS

During 2013-2014, 1,071 patients (36.3% with concomitant AF) at least 75 years old were enrolled, and the follow-up ended on July 15, 2017. Variables included sociodemographic characteristics, complications, drugs taken, laboratory results, and echocardiographic parameters. The primary end points were IS, transient ischemic attack, and TE, expressed as IS/TE. All-cause mortality was a secondary end point. Survival curves and mortality risks were assessed via Kaplan-Meier survival analysis and compared by log-rank tests.

RESULTS

The average follow-up duration was 2.57±1.37 years. Overall, 167 patients (5.6%) died and 77 (7.2%) developed IS/TE. The CHA2DS2-VASc score was associated with IS/TE in patients 75 years or older with and without AF, and patients with a CHA2DS2-VASc score ≥5 had a higher risk of stroke. However, the CHA2DS2-VASc score was not related to all-cause mortality.

CONCLUSION

The CHA2DS2-VASc score can predict IS/TE, but not mortality, in elderly patients (≥75 years) with or without AF.

Serum Uric Acid and Its Association with Longitudinal Cognitive Change Among Urban Adults

Uric acid, a waste metabolite among humans, was linked to various cognitive outcomes. We describe sex and age-group specific associations of baseline serum uric acid (SUAbase) and significant change in SUA (ΔSUA: 1 versus 0 = decrease versus no change; 2 versus 0 = increase versus no change) with longitudinal annual rate of cognitive change among a large sample of urban adults. Data from the Healthy Aging in Neighborhoods of Diversity across the Life Span study, 2004-2009 (visit 1) and 2009-2013 (visit 2) were used. Of 3,720 adults selected at baseline (age range: 30-64 y), complete data were available for N = 1,487-1,602 with a mean repeat of 1.5-1.7 visits/participant. Cognitive test domains spanned attention, processing speed, learning/memory, executive function, visuo-spatial/visuo-construction ability, language/verbal, and global cognitive function. SUA was measured at both visits. Multiple mixed-effects regression analyses were conducted. In the total population, a higher SUAbase was associated with a faster annual rate of decline on a measure of visual memory/visuo-construction ability (the Benton Visual Retention Test) by γ= 0.07 with a standard error of 0.02, p < 0.001. Among older men, a significant increase in SUA was associated with slower decline on a test of attention/processing speed, namely Trailmaking test, Part A, measured in seconds to completion (γ= -6.91 ± 1.73, p < 0.001). In sum, a higher SUAbase was associated with faster cognitive decline over-time in a visual memory/visuo-construction ability test. ΔSUA had particular beneficial effects of an increasing ΔSUA on the domain of attention/processing speed among older men. More longitudinal studies are needed to examine cognitive domain-specific effects of over-time change in SUA within sex and age groups.

High serum uric acid concentration predicts poor survival in patients with breast cancer

BACKGROUND

Uric acid is a product of purine metabolism. Recently, uric acid has gained much attraction in cancer. In this study, we aim to investigate the clinicopathological and prognostic significance of serum uric acid concentration in breast cancer patients.

METHODS

A total of 443 female patients with histopathologically diagnosed breast cancer were included. After a mean follow-up time of 56months, survival was analysed using the Kaplan-Meier method. To further evaluate the prognostic significance of uric acid concentrations, univariate and multivariate Cox regression analyses were applied.

RESULTS

Of the clinicopathological parameters, uric acid concentration was associated with age, body mass index, ER status and PR status. Univariate analysis identified that patients with increased uric acid concentration had a significantly inferior overall survival (HR 2.13, 95% CI 1.15-3.94, p=0.016). In multivariate analysis, we found that high uric acid concentration is an independent prognostic factor predicting death, but insufficient to predict local relapse or distant metastasis. Kaplan-Meier analysis indicated that high uric acid concentration is related to the poor overall survival (p=0.013).

CONCLUSIONS

High uric acid concentration predicts poor survival in patients with breast cancer, and might serve as a potential marker for appropriate management of breast cancer patients.

Serum uric acid levels and multiple health outcomes: umbrella review of evidence from observational studies, randomised controlled trials, and Mendelian randomisation studies

Objective To map the diverse health outcomes associated with serum uric acid (SUA) levels.Design Umbrella review.Data sources Medline, Embase, Cochrane Database of Systematic Reviews, and screening of citations and references.Eligibility criteria Systematic reviews and meta-analyses of observational studies that examined associations between SUA level and health outcomes, meta-analyses of randomised controlled trials that investigated health outcomes related to SUA lowering treatment, and Mendelian randomisation studies that explored the causal associations of SUA level with health outcomes.Results 57 articles reporting 15 systematic reviews and144 meta-analyses of observational studies (76 unique outcomes), 8 articles reporting 31 meta-analyses of randomised controlled trials (20 unique outcomes), and 36 articles reporting 107 Mendelian randomisation studies (56 unique outcomes) met the eligibility criteria. Across all three study types, 136 unique health outcomes were reported. 16 unique outcomes in meta-analyses of observational studies had P<10-6, 8 unique outcomes in meta-analyses of randomised controlled trials had P<0.001, and 4 unique outcomes in Mendelian randomisation studies had P<0.01. Large between study heterogeneity was common (80% and 45% in meta-analyses of observational studies and of randomised controlled trials, respectively). 42 (55%) meta-analyses of observational studies and 7 (35%) meta-analyses of randomised controlled trials showed evidence of small study effects or excess significance bias. No associations from meta-analyses of observational studies were classified as convincing; five associations were classified as highly suggestive (increased risk of heart failure, hypertension, impaired fasting glucose or diabetes, chronic kidney disease, coronary heart disease mortality with high SUA levels). Only one outcome from randomised controlled trials (decreased risk of nephrolithiasis recurrence with SUA lowering treatment) had P<0.001, a 95% prediction interval excluding the null, and no large heterogeneity or bias. Only one outcome from Mendelian randomisation studies (increased risk of gout with high SUA levels) presented convincing evidence. Hypertension and chronic kidney disease showed concordant evidence in meta-analyses of observational studies, and in some (but not all) meta-analyses of randomised controlled trials with respective intermediate or surrogate outcomes, but they were not statistically significant in Mendelian randomisation studies.Conclusion Despite a few hundred systematic reviews, meta-analyses, and Mendelian randomisation studies exploring 136 unique health outcomes, convincing evidence of a clear role of SUA level only exists for gout and nephrolithiasis.

Relationship between serum uric acid and ischemic stroke in a large type 2 diabetes population in China: A cross-sectional study

OBJECTIVE

To investigate the relationship of serum UA and ischemic stroke in type 2 diabetes patients in China.

METHOD

We examined the above relationship using the data of the project "Comprehensive Research on the Prevention and Control of the Diabetes" (CRPCD) study. A total of 19,442 participants were enrolled in the cross-sectional study. The enrolled participants were divided into quintiles of the serum UA levels with cut off values for two age groups (<60 versus ≥60years). Binary logistic regression analyses were used to evaluate whether the levels of serum UA were independently associated with ischemic stroke in type 2 diabetes.

RESULTS

The serum UA levels were significantly higher in the participants with age≥60years than those with age<60years (P=0.000). In the age group of <60years, the odds ratio for ischemic stroke with type 2 diabetes in quintile 5 over quintile 1 was 2.420 (95% CI, 1.566-3.470) in the unadjusted model and 1.765 (95% CI, 1.097-2.840) after controlling potential confounders. However, the reverse results were observed in the age group of ≥60years. The odds ratio in quintile 4 over quintile 1 in model 3 and model 4 were 0.767 (95% CI, 0.630-0.934) and 0.782 (95% CI, 0.640-0.957).

CONCLUSION

Our results indicated that serum UA levels were independently positively associated with ischemic stroke in patients aged <60years, but the association was U-shaped in patients aged ≥60years.

Glucose in prediabetic and diabetic range and outcome after stroke

OBJECTIVES

Newly diagnosed disturbed glucose metabolism is highly prevalent in patients with stroke. Limited data are available on their prognostic value on outcome after stroke. We aimed to assess the association of glucose in the prediabetic and diabetic range with unfavourable short-term outcome after stroke.

MATERIALS AND METHODS

We included 839 consecutive patients with ischemic stroke and 168 patients with intracerebral haemorrhage. In all nondiabetic patients, fasting glucose levels were determined on day 2-4. Prediabetic range was defined as fasting glucose of 5.6-6.9 mmol/L, diabetic range as ≥7.0 mmol/L, pre-existent diabetes as the use of anti-diabetic medication prior to admission. Outcome measures were poor functional outcome or death defined as modified Rankin Scale (mRS) score >2 and discharge not to home. The association of prediabetic range, diabetic range and pre-existent diabetes (versus normal glucose) with unfavourable outcome was expressed as odds ratios, estimated with multiple logistic regression, with adjustment for prognostic factors.

RESULTS

Compared with normal glucose, prediabetic range (aOR 1.8; 95%CI 1.1-2.8), diabetic range (aOR 2.5; 95%CI 1.3-4.9) and pre-existent diabetes (aOR 2.6; 95%CI 1.6-4.0) were associated with poor functional outcome or death. Patients in the prediabetic range (aOR 0.6; 95%CI 0.4-0.9), diabetic range (aOR 0.4; 95%CI 0.2-0.9) and pre-existent diabetes (aOR 0.6; 95%CI 0.4-0.9) were more likely not to be discharged to home.

CONCLUSIONS

Patients with glucose in the prediabetic and diabetic range have an increased risk of unfavourable short-term outcome after stroke. These findings illustrate the potential impact of early detection and treatment of these patients.

Association between prediabetes and risk of cardiovascular disease and all cause mortality: systematic review and meta-analysis

OBJECTIVES

 To evaluate associations between different definitions of prediabetes and the risk of cardiovascular disease and all cause mortality.

DESIGN

 Meta-analysis of prospective cohort studies.

DATA SOURCES

 Electronic databases (PubMed, Embase, and Google Scholar).

SELECTION CRITERIA

 Prospective cohort studies from general populations were included for meta-analysis if they reported adjusted relative risks with 95% confidence intervals for associations between the risk of composite cardiovascular disease, coronary heart disease, stroke, all cause mortality, and prediabetes.

REVIEW METHODS

 Two authors independently reviewed and selected eligible studies, based on predetermined selection criteria. Prediabetes was defined as impaired fasting glucose according to the criteria of the American Diabetes Association (IFG-ADA; fasting glucose 5.6-6.9 mmol/L), the WHO expert group (IFG-WHO; fasting glucose 6.1-6.9 mmol/L), impaired glucose tolerance (2 hour plasma glucose concentration 7.8-11.0 mmol/L during an oral glucose tolerance test), or raised haemoglobin A_1c (HbA_1c) of 39-47 mmol/mol : (5.7-6.4%) according to ADA criteria or 42-47 mmol/mol (6.0-6.4%) according to the National Institute for Health and Care Excellence (NICE) guideline. The relative risks of all cause mortality and cardiovascular events were calculated and reported with 95% confidence intervals.

RESULTS

 53 prospective cohort studies with 1 611 339 individuals were included for analysis. The median follow-up duration was 9.5 years. Compared with normoglycaemia, prediabetes (impaired glucose tolerance or impaired fasting glucose according to IFG-ADA or IFG-WHO criteria) was associated with an increased risk of composite cardiovascular disease (relative risk 1.13, 1.26, and 1.30 for IFG-ADA, IFG-WHO, and impaired glucose tolerance, respectively), coronary heart disease (1.10, 1.18, and 1.20, respectively), stroke (1.06, 1.17, and 1.20, respectively), and all cause mortality (1.13, 1.13 and 1.32, respectively). Increases in HBA_1c to 39-47 mmol/mol or 42-47 mmol/mol were both associated with an increased risk of composite cardiovascular disease (1.21 and 1.25, respectively) and coronary heart disease (1.15 and 1.28, respectively), but not with an increased risk of stroke and all cause mortality.

CONCLUSIONS

 Prediabetes, defined as impaired glucose tolerance, impaired fasting glucose, or raised HbA_1c, was associated with an increased risk of cardiovascular disease. The health risk might be increased in people with a fasting glucose concentration as low as 5.6 mmol/L or HbA_1c of 39 mmol/mol.

Mild hyponatremia, hypernatremia and incident cardiovascular disease and mortality in older men: A population-based cohort study

AIM

To examine the association between serum sodium concentration and incident major cardiovascular disease (CVD) outcomes and total mortality in older men.

METHODS AND RESULTS

A prospective study of 3099 men aged 60-79 years without a history of cardiovascular disease followed up for an average 11 years during which there were 528 major CVD events (fatal coronary heart disease [CHD] and non-fatal MI, stroke and CVD death) and 873 total deaths. A U shaped relationship was seen between serum sodium concentration and major CVD events and mortality. Hyponatremia (<136 mEq/L) and low sodium within the normal range (136-138 mEq/L) showed significantly increased risk of major CVD events and total mortality compared to men within the upper normal range (139-143 mEq/L) after adjustment for a wide range of confounders and traditional risk factors [adjusted HRs 1.55 (1.13,2.12) and 1.40 (1.14,1.72) for major CVD events respectively and 1.30 (1.02,1.66) and 1.30 (1.11,1.53) respectively for total mortality]. Hyponatremia was associated with inflammation, NT-proBNP, low muscle mass and alkaline phosphatase; these factors contributed to the increased total mortality associated with hyponatremia but did not explain the increased risk of CVD events associated with hyponatremia or low normal sodium concentration. Hypernatremia (≥145 mEq/L) was associated with significantly increased risk of CVD events and mortality due to CVD causes.

CONCLUSION

Mild hyponatremia even within the normal sodium range and hypernatremia are both associated with increased total mortality and major CVD events in older men without CVD which is not explained by known adverse CV risk factors.

Impact of sex on uric acid levels and its relationship with the extent of coronary artery disease: A single-centre study

BACKGROUND

Serum uric acid (SUA) elevation has been largely addressed in the past as a possible risk factor for cardiovascular disease. However, uric acid has not clearly emerged as independent risk factor for coronary artery disease. Several studies in literature have assessed sex-related differences in the association between elevated SUA levels and cardiovascular events with conflicting results. Therefore, aim of the current study was to evaluate the relationship between uric acid levels and the extent of coronary artery disease in male and female patients undergoing coronary angiography.

METHODS

Our population is represented by 3520 consecutive patients undergoing coronary angiography from March 2007 to October 2012. Patients were divided according to Tertiles of SUA (Males, Group 1, ≤5.5 mg/dL-0.33 mmol/mol, n = 762, Group 2, 5.5-6.8 mg/dL-0.33-0.40 mmol/mol, n = 829 and Group 3 ≥6.8 mg/dL-0.40 mmol/mol, n = 851), (Females, Group 1, ≤4.8 mg/dL-0.28 mmol/mol, n = 349, Group 2, 4.8-6.3 mg/dL-0.28-0.37 mmol/mol, n = 359 and Group 3 ≥ 6.3 mg/dL-0.37 mmol/mol, n = 370). Fasting samples were collected for uric acid levels assessment. Coronary disease was defined for at least 1 vessel stenosis >50% as evaluated by QCA. Severe coronary disease was defined as three-vessel disease and/or left main disease.

RESULTS

Among 3520 patients, we identified 2442 men (69.4%) and 1078 women (30.6%). Males had higher levels of uric acid than women (6.33 ± 1.7 vs 5.8 ± 1.9 - p < 0.001). The association between elevated uric acid (≥7 mg/dl or 0.42 mmol/l) and male gender was confirmed after correction for baseline confounding factors (Adjusted OR = 1.28 [1.01-1.62], p = 0.004). Males displayed a significantly higher prevalence and extent of CAD (p < 0.001) and more complex coronary lesions (p < 0.001). However, no significant relationship was observed between uric acid and CAD (Adjusted OR [95%CI] = 0.90 [0.76-1.06], p = 0.22) or severe CAD (Adjusted OR [95%CI] = 0.89 [0.79-1.01], p = 0.08). Among females, higher SUA levels were significantly associated with higher prevalence of severe CAD (p < 0.001) (Adjusted OR [95% CI] = 1.29 [1.03-1.62], p = 0.03).

CONCLUSION

Our study showed that uric acid levels are significantly higher in men. However, high uric acid levels are associated with severe CAD only in women. Future large studies are certainly needed to confirm our findings and to evaluate the effects of SUA lowering therapies on cardiovascular prevention and outcome, especially in women.

Associations of prediabetes with all-cause and cardiovascular mortality: a meta-analysis

BACKGROUND

Reports on the association of prediabetes with all-cause mortality and cardiovascular mortality are inconsistent. Objective. To evaluate the risk of all-cause and cardiovascular mortality in association with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT).

METHODS

Prospective cohort studies with data on prediabetes and mortality were included. The relative risks (RRs) of all-cause and cardiovascular mortality were calculated and reported with 95% confidence intervals (95% CIs).

RESULTS

Twenty-six studies were included. The risks of all-cause and cardiovascular mortality were increased in participants with prediabetes defined as IFG of 110-125 mg/dL (IFG 110) (RR 1.12, 95% CI 1.05-1.20; and RR 1.19, 95% CI 1.05-1.35, respectively), IGT (RR 1.33, 95% CI 1.24-1.42; RR 1.23, 95% CI 1.11-1.36, respectively), or combined IFG 110 and/or IGT (RR 1.21, 95% CI 1.11-1.32; RR 1.21, 95% CI 1.07-1.36, respectively), but not when IFG was defined as 100-125 mg/dL (RR 1.07, 95% CI 0.92-1.26; and RR 1.16, 95% CI 0.94-1.42, respectively).

CONCLUSIONS

Prediabetes, defined as IFG 110, IGT, or combined IFG 110 and/or IGT, was associated with increased all-cause and cardiovascular mortality.

Association of uric acid and carotid artery disease in patients with ischemic stroke

BACKGROUND AND PURPOSE

Some previous studies reported an independent association between uric acid and coronary artery disease, while little is known on the association among uric acid and carotid artery disease (CAD). To address this issue, we investigated the association between CAD and higher uric acid level because of the well-known importance of the carotid artery pathologies for ischemic stroke.

METHODS

Between 2009 and 2012, we conducted a study among 406 consecutive first-ever ischemic stroke patients to assess the relationship between uric acid and carotid artery. A mean intima-media thickness IMT was calculated for the wall of the left and right common carotid arteries (CCA) and IMT of the bifurcation of the carotid arteries. CAD was assessed by neuroimaging techniques in patients with carotid artery stenosis more than 50%. Logistic regression models were used to determine the relation among pathological changes of the carotid artery and higher uric acid level.

RESULTS

In patients with hyperuricemia, the frequency of age (>60 years), hypertriglyceridemia, higher apo B, renal failure were significantly higher than those with normal uric acid level. CAD was more frequent in patients with hyperuricemia than those with normal uric acid level (OR, 1.8, 95% CI, 1.1-3.1; P = 0.01). In patients with higher uric acid level, the mean of the IMT of the CCA and of the bifurcation of the carotid artery were higher than those with normal uric acid level (P = 0.001 for each). Covariance matrix analysis displayed a strong correlation between CAD and age (>60 years) (P < 0.05), sex (P < 0.01), hyperuricemia (P < 0.01), hypertension (P < 0.05), and hypercholesterolemia (P < 0.05). In the models of regression analysis, a strong association was found among patients with CAD and sex, renal failure, hyperuricemia, number of plaques, and size of plaques.

CONCLUSION

Our study demonstrated that higher uric acid level is strongly associated with CAD. Elevated uric acid might be injurious for large cerebral arteries with some probable confounding risk factors. Further prospective large clinical trials will determine whether lowering uric acid level reduces the frequency of CAD and ischemic stroke.

Serum uric acid levels and the risk of impaired fasting glucose: a prospective study in adults of north China

OBJECTIVE

To prospectively investigate the association between serum uric acid (SUA) level and incidence of impaired fasting glucose (IFG) in adult Chinese.

METHODS

We evaluated 13,328 women and 41,350 men without diabetes and IFG. The participants were classified into quintile according to baseline level of SUA. Data were analyzed to examine the association between SUA levels and the incidence of IFG. We used Cox regression models to estimate the relative risk of IFG after adjusting for known risk factors.

RESULTS

For men, the second quintile of SUA has the lowest cumulative incidence of IFG (29.9%); the fifth quintile of SUA has the highest cumulative incidence of IFG (35.6%). After corrected with Cox regression, the first quartile and the fourth quartile have higher cumulative incidence of IFG than the second quintile, with the HR of 1.11(1.05-1.17) and 1.07(1.01-1.13), respectively. For women, the first quartile of SUA has the lowest cumulative incidence of IFG (20.7%), while the fifth quintile of SUA has the highest cumulative incidence of IFG (30.0%). However, there is no significant difference in IFG between different quintile after adjusted with Cox regression.

CONCLUSIONS

The results of this prospective study suggest that there is a higher risk of developing IFG in association with low or high SUA concentrations for men. These relationships were independent of other known risk factors. There is no significant correlation in the risk of developing IFG in association with SUA concentrations for women. Analyses excluding participants with hypertension or with hyperlipidemia and analyses with participants stratified by age reached similar conclusion.

Hyperuricemia and risk of stroke: a systematic review and meta-analysis of prospective studies

INTRODUCTION

Hyperuricemia may be associated with an increased risk of stroke, but to date results from prospective studies have been inconsistent. This study aimed to evaluate the association between hyperuricemia and risk of stroke incidence and mortality by performing a meta-analysis.

MATERIALS AND METHODS

Studies were identified by searching multiple electronic databases through July 13, 2013, and by reviewing reference lists of obtained articles. Prospective studies reported a multivariate-adjusted estimate, represented as relative risk (RRs) with 95% confidence intervals (CIs) for the association between hyperuricemia and risk of stroke incidence and mortality were eligible. A random-effects model was used to compute the pooled risk estimate.

RESULTS

A total of fourteen articles including results from 15 prospective studies with 22,571 cases of stroke and 1,042,358 participants were included in the meta-analysis. Overall, presence of hyperuricemia was associated with a significantly greater risk of both stroke incidence (RR, 1.22; 95% CI, 1.02-1.46) and mortality (RR, 1.33; 95% CI, 1.24-1.43). In addition, the pooled estimate of multivariate RRs of stroke incidence and mortality were 1.08 (95% CI: 0.85-1.38); 1.26 (95% CI: 1.14-1.40) among men and 1.25 (95% CI: 1.04-1.46); 1.41 (95% CI: 1.31-1.52) among women respectively.

CONCLUSIONS

Results from this meta-analysis indicate that hyperuricemia may modestly increase the risks of both stroke incidence and mortality. Future studies should explore whether hyperuricemia is a modifiable risk factor for stroke.

Serum uric acid and cardio-renal diseases

OBJECTIVES

In this article, the results of clinical and experimental studies that examine the association of hyperuricemia and gout with hypertension and kidney disease are presented and discussed.

METHODS

Key papers for inclusion were identified by a PubMed search, and articles were selected according to their relevance for the topic, according to the authors' judgment.

RESULTS AND CONCLUSIONS

Increasing evidence supports a causal role for Uric acid (UA) in hypertension. Further larger studies are needed to confirm the possible beneficial role of UA lowering drugs and/or xantine-oxidase (XO) inhibitors. Overall, clinical evidence suggests a relationship of UA level with incident chronic kidney disease (CKD). In addition, the results of clinical trials using urate lowering therapy provide some promising evidence that lowering UA levels may retard the progression of CKD. Reviewed data indicate the need for large, well designed studies in these patients to evaluate XO inhibitors or uricosuric drugs in cardio-renal diseases and further elucidate the role of UA in the development and progression of CKD.

Hyperuricemia and hypertension

Over the past century, uric acid has been considered a possible risk factor for hypertension and cardiovascular disease. However, only in the past decade, animal models and clinical trials have supported a more mechanistic link. Results from animal models suggest a 2-phase mechanism for the development of hyperuricemic hypertension in which uric acid induces acute vasoconstriction by activation of renin-angiotensin system, followed by uric acid uptake into vascular smooth muscle cells leading to cellular proliferation and secondary arteriolosclerosis that impairs pressure natriuresis. This acute hypertension remains uric acid dependent and sodium independent, whereas the chronic hypertension becomes uric acid independent and sodium dependent. Small clinical trials, performed in adolescents with newly diagnosed essential hypertension, demonstrate that reduction of serum uric acid can reduce blood pressure. Although more research is clearly necessary, the available data suggest that uric acid is likely causative in some cases of early onset hypertension.

Relationship between serum uric acid and cerebral white matter lesions in the elderly

BACKGROUND AND AIMS

Recent evidence suggests that hyperuricemia might increase the risk of cardiovascular disease. Cardiovascular risk factors are well recognized to be associated with cerebral white matter lesion (WML). We hypothesized that hyperuricemia is related to higher grade of WML in both men and women.

METHODS AND RESULTS

A total of 108 men and 123 women were enrolled from those who signed up for the annual Health Examination for the Elderly Program in Taipei from 2006 to 2008. Information in interview data, clinical and laboratory examinations were collected. Hyperuricemia was defined by uric acid ≥458.0 μmol/L in men and ≥392.6 μmol/L in women. Two types of WML including periventricular hyper-intensity (PVH) and deep white matter hyper-intensity (DWMH), ascertained by cranial magnetic resonance imaging, were graded. Association between hyperuricemia and high grade WML was evaluated by using multiple logistic regression analysis. The prevalences of hyperuricemia were 13.9% and 17.9% for men and women, respectively. The prevalences of moderate-to-severe PVH among men and women were 16.7% and 7.3%; while the prevalences of moderate-to-severe DWMH for men and women were 19.4% and 11.4%, respectively. Hyperuricemia was related to moderate-to-severe DWMH in men, after controlling for age, education years, smoking, alcohol consumption, metabolic Z score, silent infarct, and the use of anti-hypertensives, lipid-lowering and anti-diabetic agents, the association remained significant. The relationship was not evident among women. We did not find an association between hyperuricemia and PVH.

CONCLUSIONS

Hyperuricemia was positively associated with high grade DWMH in older men, but not in women.

Increased serum levels of uric acid are associated with sudomotor dysfunction in subjects with type 2 diabetes mellitus

The aim of this paper was to assess serum uric acid (SUA) levels in patients with type 2 diabetes mellitus (T2DM) with or without sudomotor dysfunction (evaluated by the Neuropad test). We included 36 T2DM patients with sudomotor dysfunction (group A: mean age 63.1 ± 2.6 years) and 40 age-, gender-, renal function- and T2DM duration-matched patients without sudomotor dysfunction (group B: mean age 62.1 ± 3.1 years). SUA was significantly higher in group A (P < 0.001). There was a significant correlation between SUA and Neuropad time to colour change in both groups (group A: r_s = 0.819, P < 0.001; group B: r_s = 0.774, P < 0.001). There was also a significant positive correlation between SUA and CRP in both groups (group A: r_s = 0.947, P < 0.001; group B: r_s = 0.848, P < 0.001). In conclusion, SUA levels were higher in T2DM patients with sudomotor dysfunction than those without this complication. The potential role of SUA in sudomotor dysfunction merits further study.

Peripheral neuropathy is associated with increased serum levels of uric acid in type 2 diabetes mellitus

We assessed serum uric acid (SUA) levels in patients with type 2 diabetes mellitus (T2DM) with or without peripheral neuropathy (diagnosed by the Neuropathy Disability score [NDS]). We enrolled 64 patients with T2DM with peripheral neuropathy (group A: 31 men, mean age 63.0 ± 2.8 years) and 66 age-, gender-, renal function- and T2DM duration-matched patients without neuropathy (group B: 32 men, mean age 62.4 ± 3.1 years). Serum uric acid was significantly higher in group A (P < .001). There was a significant correlation between SUA and NDS in both groups (group A: r(s) = .93, P < .001; group B: r( s) = .95, P < .001). C-reactive protein (CRP) was also significantly higher in group A (P < .001) and correlated significantly with SUA in both groups (group A: r(s) = .93, P < .001; group B: r(s) = .87, P < .001). Serum uric acid is increased in patients with T2DM with neuropathy versus those without. Whether SUA is involved in the pathogenesis of T2DM peripheral neuropathy remains to be established.

Combination of uric acid and NT-ProBNP: a more useful prognostic marker for short-term clinical outcomes in patients with acute heart failure

BACKGROUND/AIMS

In patients with heart failure (HF), N-terminal prohormone brain natriuretic peptide (NT-ProBNP) is a standard prognostic indicator. In addition, uric acid (UA) was recently established as a prognostic marker for poor outcome in chronic HF. The aim of this study was to determine the combined role of UA and NT-ProBNP as prognostic markers for short-term outcomes of acute heart failure (AHF).

METHODS

The levels of UA and NT-ProBNP were determined in 193 patients (age, 69 ± 13 years; 76 males) admitted with AHF. Patients were followed for 3 months and evaluated for cardiovascular events, defined as cardiac death and/or readmission for HF.

RESULTS

Of the 193 patients, 23 (11.9%) died and 20 (10.4%) were readmitted for HF during the 3-month follow-up period. Based on univariate analysis, possible predictors of short-term cardiovascular events were high levels of UA and NT-ProBNP, low creatinine clearance, no angiotensin converting enzyme inhibitors or angiotensin receptor blockers, and old age. Multivariate Cox hazard analysis showed that UA levels were independently associated with increased incidence of cardiovascular events (hazard ratio, 1.115; 95% confidence interval, 1.006 to 1.235; p = 0.037). Kaplan-Meier survival analysis revealed that patients with UA levels > 8.0 mg/dL and NT-ProBNP levels > 4,210 pg/mL were at highest risk for cardiac events (p = 0.01).

CONCLUSIONS

The combination of UA and NT-ProBNP levels appears to be more useful than either marker alone as an independent predictor for short-term outcomes in patients with AHF.

Hyperuricemia and coronary heart disease: a systematic review and meta-analysis

OBJECTIVE

The role of serum uric acid as an independent risk factor for cardiovascular disease remains unclear, although hyperuricemia is associated with cardiovascular disease such as coronary heart disease (CHD), stroke, and hypertension.

METHODS

A systematic review and meta-analysis using a random-effects model was conducted to determine the risk of CHD associated with hyperuricemia in adults. Studies of hyperuricemia and CHD were identified by searching major electronic databases using the medical subject headings and keywords without language restriction (through February 2009). Only prospective cohort studies were included if they had data on CHD incidences or mortalities related to serum uric acid levels in adults.

RESULTS

Twenty-six eligible studies of 402,997 adults were identified. Hyperuricemia was associated with an increased risk of CHD incidence (unadjusted risk ratio [RR] 1.34, 95% confidence interval [95% CI] 1.19-1.49) and mortality (unadjusted RR 1.46, 95% CI 1.20-1.73). When adjusted for potential confounding, the pooled RR was 1.09 (95% CI 1.03-1.16) for CHD incidence and 1.16 (95% CI 1.01-1.30) for CHD mortality. For each increase of 1 mg/dl in uric acid level, the pooled multivariate RR for CHD mortality was 1.12 (95% CI 1.05-1.19). Subgroup analyses showed no significant association between hyperuricemia and CHD incidence/mortality in men, but an increased risk for CHD mortality in women (RR 1.67, 95% CI 1.30-2.04).

CONCLUSION

Hyperuricemia may marginally increase the risk of CHD events, independently of traditional CHD risk factors. A more pronounced increased risk for CHD mortality in women should be investigated in future research.

Hyperuricemia and coronary heart disease: a systematic review and meta-analysis

OBJECTIVE

The role of serum uric acid as an independent risk factor for cardiovascular disease remains unclear, although hyperuricemia is associated with cardiovascular disease such as coronary heart disease (CHD), stroke, and hypertension.

METHODS

A systematic review and meta-analysis using a random-effects model was conducted to determine the risk of CHD associated with hyperuricemia in adults. Studies of hyperuricemia and CHD were identified by searching major electronic databases using the medical subject headings and keywords without language restriction (through February 2009). Only prospective cohort studies were included if they had data on CHD incidences or mortalities related to serum uric acid levels in adults.

RESULTS

Twenty-six eligible studies of 402,997 adults were identified. Hyperuricemia was associated with an increased risk of CHD incidence (unadjusted risk ratio [RR] 1.34, 95% confidence interval [95% CI] 1.19-1.49) and mortality (unadjusted RR 1.46, 95% CI 1.20-1.73). When adjusted for potential confounding, the pooled RR was 1.09 (95% CI 1.03-1.16) for CHD incidence and 1.16 (95% CI 1.01-1.30) for CHD mortality. For each increase of 1 mg/dl in uric acid level, the pooled multivariate RR for CHD mortality was 1.12 (95% CI 1.05-1.19). Subgroup analyses showed no significant association between hyperuricemia and CHD incidence/mortality in men, but an increased risk for CHD mortality in women (RR 1.67, 95% CI 1.30-2.04).

CONCLUSION

Hyperuricemia may marginally increase the risk of CHD events, independently of traditional CHD risk factors. A more pronounced increased risk for CHD mortality in women should be investigated in future research.

Hyperuricemia and risk of stroke: a systematic review and meta-analysis

OBJECTIVE

To assess the association between hyperuricemia and risk of stroke incidence and mortality because hyperuricemia is hypothesized to be a risk factor for stroke and other cardiovascular disease, but, to date, results from observational studies are conflicting.

METHODS

A systematic review and meta-analysis were conducted. Studies were identified by searching major electronic databases using the Medical Subject Headings and keywords without restriction in languages. Prospective cohort studies were included only if they contained data on stroke incidences or mortalities related to serum uric acid levels in adults. Pooled risk ratios (RRs) for the association of stroke incidence and mortality with serum uric acid levels were calculated.

RESULTS

A total of 16 studies including 238,449 adults were eligible and abstracted. Hyperuricemia was associated with a significantly higher risk of both stroke incidence (6 studies; RR 1.41, 95% confidence interval [95% CI] 1.05, 1.76) and mortality (6 studies; RR 1.36, 95% CI 1.03, 1.69) in our meta-analyses of unadjusted study estimates. Subgroup analyses of studies adjusting for known risk factors such as age, hypertension, diabetes mellitus, and cholesterol still showed that hyperuricemia was significantly associated with both stroke incidence (4 studies; RR 1.47, 95% CI 1.19, 1.76) and mortality (6 studies; RR 1.26, 95% CI 1.12, 1.39). The pooled estimate of multivariate RRs did not differ significantly by sex.

CONCLUSION

Hyperuricemia may modestly increase the risks of both stroke incidence and mortality. Future research is needed to determine whether lowering uric acid level has any beneficial effects on stroke.

Uric acid: the oxidant-antioxidant paradox

Uric acid, despite being a major antioxidant in the human plasma, both correlates and predicts development of obesity, hypertension, and cardiovascular disease, conditions associated with oxidative stress. While one explanation for this paradox could be that a rise in uric acid represents an attempted protective response by the host, we review the evidence that uric acid may function either as an antioxidant (primarily in plasma) or pro-oxidant (primarily within the cell). We suggest that it is the pro-oxidative effects of uric acid that occur in cardiovascular disease and may have a contributory role in the pathogenesis of these conditions.

Use of penalized splines in extended Cox-type additive hazard regression to flexibly estimate the effect of time-varying serum uric acid on risk of cancer incidence: a prospective, population-based study in 78,850 men

PURPOSE

We sought to investigate the effect of serum uric acid (SUA) levels on risk of cancer incidence in men and to flexibly determine the shape of this association by using a novel analytical approach.

METHODS

A population-based cohort of 78,850 Austrian men who received 264,347 serial SUA measurements was prospectively followed-up for a median of 12.4 years. Data were collected between 1985 and 2003. Penalized splines (P-splines) in extended Cox-type additive hazard regression were used to flexibly model the association between SUA, as a time-dependent covariate, and risk of overall and site-specific cancer incidence and to calculate adjusted hazard ratios with their 95% confidence intervals.

RESULTS

During follow-up 5189 incident cancers were observed. Restricted maximum-likelihood optimizing P-spline models revealed a moderately J-shaped effect of SUA on risk of overall cancer incidence, with statistically significantly increased hazard ratios in the upper third of the SUA distribution. Increased SUA (>/=8.00 mg/dL) further significantly increased risk for several site-specific malignancies, with P-spline analyses providing detailed insight about the shape of the association with these outcomes.

CONCLUSIONS

Our study is the first to demonstrate a dose-response association between SUA and cancer incidence in men, simultaneously reporting on the usefulness of a novel methodological framework in epidemiologic research.

The role of uric acid in stroke: the issue remains unresolved

BACKGROUND

Although in the past decade a large number of studies have been performed to identify the relationship between uric acid and stroke, the issue remains unresolved and it is not clear whether the correlation between uric acid and stroke is circumstantial or causal.

REVIEW SUMMARY

Some studies have found uric acid predictive for the development of cardiovascular disease, whereas others have failed to identify uric acid as a significant and independent risk factor after controlling for other atherosclerotic risk factors. Furthermore, uric acid, a powerful endogenous antioxidant, is increased in oxidative stress situations such as stroke. Still, it remains controversial whether elevated serum uric acid is neuroprotective or injurious at the onset of acute stroke.

CONCLUSIONS

Large trials are required to provide definite answers in clinical practice and to reevaluate the goals of hypouricemic treatment in subjects with increased cardiovascular risk or during an acute cardiovascular event like stroke. This review tries to keep pace with the data concerning the association between uric acid and stroke.