Serum uric acid level and its association with metabolic syndrome and carotid atherosclerosis in patients with type 2 diabetes

Contribution of Inflammation, Oxidative Stress, and Antioxidants to the Relationship between Sleep Duration and Cardiometabolic Health

OBJECTIVES

To explore the interrelationship and mediating effect of factors that are beneficial (i.e., antioxidants) and harmful (i.e., inflammation and oxidative stress) to the relationship between sleep and cardiometabolic health.

DESIGN

Cross-sectional data from the 2005-2006 National Health and Nutrition Examination Survey.

SETTING

Nationally representative population sample from the US.

PARTICIPANTS

Age ≥ 20 y with sleep data; final analytical sample of n = 2,079.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Metabolic syndrome was classified according to the Joint Interim Statement, and sleep duration was categorized as very short, short, adequate, and long sleepers (≤ 4, 5-6, 7-8, and ≥ 9 h per night, respectively). The indirect mediation effect was quantified as large (≥ 0.25), moderate (≥ 0.09), modest (≥ 0.01), and weak (< 0.01). In general, inflammation was above the current clinical reference range across all sleep duration categories, whereas oxidative stress was elevated among short and very short sleepers. Select sleep duration- cardiometabolic health relationships were mediated by C-reactive protein (CRP), γ-glutamyl transferase (GGT), carotenoids, uric acid, and vitamins C and D, and were moderated by sex. Specifically, moderate-to-large indirect mediation by GGT, carotenoids, uric acid, and vitamin D were found for sleep duration-waist circumference and -systolic blood pressure relationships, whereas vitamin C was a moderate mediator of the sleep duration-diastolic blood pressure relationship.

CONCLUSIONS

Several factors related to inflammation, oxidative stress, and antioxidant status were found to lie on the casual pathway of the sleep duration-cardiometabolic health relationship. Further longitudinal studies are needed to confirm our results.

A genetic marker of hyperuricemia predicts cardiovascular events in a meta-analysis of three cohort studies in high risk patients

INTRODUCTION

The strongest genetic marker of uric acid levels, the rs734553 SNP in the GLUT9 urate transporter gene, predicts progression to kidney failure in CKD patients and associates with systolic BP and carotid intima media thickness in family-based studies.

METHODS

Since genes are transmitted randomly (Mendelian randomization) we used this gene polymorphism as an unconfounded research instrument to further explore the link between uric acid and cardiovascular disease (cardiovascular death, and non-fatal myocardial infarction and stroke) in a meta-analysis of three cohort studies formed by high risk patients (MAURO: 755 CKD patients; GHS: 353 type 2 diabetics and coronary artery disease and the TVAS: 119 patients with myocardial infarction).

RESULTS

In separate analyses of the three cohorts, the incidence rate of CV events was higher in patients with the rs734553 risk (T) allele (TT/GT) than in those without (GG patients) and the HR in TT/GT patients in the three cohorts (range 1.72-2.14) coherently signaled an excessive cardiovascular risk with no heterogeneity (I2 = 0.01). The meta-analytical estimate (total number of patients, n = 1227; total CV events, n = 222) of the HR for the combined end-point in TT/GT patients was twice higher (pooled HR: 2.04, 95% CI: 1.11-3.75, P = 0.02) than in GG homozygotes.

CONCLUSIONS

The T allele of the rs734553 polymorphism in the GLUT9 gene predicts a doubling in the risk for incident cardiovascular events in patients at high cardiovascular risk. Findings in this study are compatible with the hypothesis of a causal role of hyperuricemia in cardiovascular disease in high risk conditions.

Chemerin is not associated with subclinical atherosclerosis markers in prediabetes and diabetes

OBJECTIVE

Chemerin is a novel adipokine that is correlated with adipocyte differentiation, glucose metabolism, and inflammation. We aimed to investigate the relation between serum chemerin level and subclinical atherosclerosis markers as exemplified by brachial artery pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), epicardial fat thickness (EFT), and carotid plaque presence in diabetes and prediabetes.

METHODS

Age-, body mass index (BMI)-, and gender-matched patients with type 2 DM (n=30), prediabetes (n=25), and normal glucose tolerance (n=25) were included in this cross-sectional study. Serum chemerin level, lipid parameters, glucose metabolism marker, baPWV, CIMT, EFT, and anthropometric were recorded. The independent risk factors for atherosclerosis markers were determined by linear and/or multiple logistic regression analysis.

RESULTS

baPWV and carotid plaque presence were higher in the diabetes group than in prediabetes and control groups (p=0.039 and p=0.035 respectively), whereas serum chemerin levels were similar among groups (p=0.338). Chemerin levels were not correlated with PWV, CIMT, and epicardial fat thickness overall or in the subgroups. Overall and in the diabetes group, chemerin levels were positively correlated with the key components of metabolic syndrome as BMI, total body fat percentage, waist circumference, triglyceride, and systolic and diastolic blood pressure (BP). After adjusting for age, gender, and BMI, only the association between chemerin and systolic BP remained significant. Chemerin was not found as an independent risk factor for predicting atherosclerosis in diabetes and prediabetes.

CONCLUSION

Chemerin is not a predictive marker for atherosclerosis in diabetes and prediabetes, but correlates well with key aspects of the metabolic syndrome particularly in diabetes.

The association between serum uric acid levels, metabolic syndrome and cardiovascular disease in middle aged and elderly Chinese: results from the DYSlipidemia International Study

Background

To explore the association between serum uric acid (SUA) levels, metabolic syndrome (MetS) and cardiovascular disease (CVD) in patients treated with lipid-lowering agents from multiple centers in China.

Method

We investigated 15,478 participants who had been documented with recorded SUA in the DYSlipidemia International Study which included 25,697 patients, aged 45 years old or older, who were treated with lipid-lowering agents from 122 centers between April 2012 and October 2012. Logistic regression analysis was performed to examine the association between SUA levels, MetS and CVD.

Result

After adjusting for multi-variables, hyperuricemia (the highest category of SUA level) showed a significantly higher risk of MetS compared to the lowest category[according to NCEP-ATPIII criteria, odds ratio (OR) 1.51, 95 % confidence interval (CI) (1.30,1.74) in men, OR 2.35 95 % CI (2.00,2.75) in women; and according to IDF criteria, OR 1.40 95 % CI (1.20,1.63) in men, OR 1.65 95 % CI (1.41,1.94) in women]. In addition, elevated SUA concentration was shown to be associated with coronary heart disease (CHD) (OR 1.26 95 % CI (1.09, 1.45) in men, and OR 1.27, 95 % CI (1.07, 1.50) in women) and heart failure (HF) (OR 1.61 95 % CI (1.15, 2.24) in men, and OR 1.91, 95 % CI (1.29, 2.82) in women).

Conclusion

Our research suggested a positive association between SUA levels and MetS in Chinese patients receiving lipid-lowering therapy. Elevated SU levels were positively associated independently of measured confounders to CHD and HF.

Decreased urine uric acid excretion is associated with diabetic retinopathy but not with lower limb atherosclerosis in hospitalized patients with type 2 diabetes

OBJECTIVE

To explore the associations between urine uric acid excretion (UUAE) and diabetic retinopathy (DR)/lower limb atherosclerotic lesions in hospitalized Chinese patients with type 2 diabetes.

METHODS

This cross-sectional study was conducted in 2529 hospitalized Chinese patients with type 2 diabetes. UUAE was determined enzymatically using a single 24-h urine collection. The subjects were stratified into quartile based on UUAE levels. DR was determined by digital fundus photography. Lower limb atherosclerotic lesions were assessed by Doppler ultrasound. Both DR and lower limb atherosclerosis were compared among the UUAE quartile groups, respectively.

RESULTS

There was a significant decrease in the prevalence of DR in patients across the UUAE quartiles after adjustment for sex, age and diabetic duration (35.0%, 30.7%, 26.1%, and 21.5%, respectively, p = 0.000001 for trend). A fully adjusted multiple logistic regression analyses revealed that UUAE quartiles were markedly inversely associated with the presence of DR (p = 0.030). The prevalence of lower limb plaque (73.9% vs. 62.6%, p = 0.000044) and stenosis (16.3% vs. 9.7%, p = 0.000015) was markedly higher in the diabetics with DR than in those without DR. However, there was no statistical association between the UUAE and lower limb atherosclerotic lesions in type 2 diabetes.

CONCLUSIONS

Decreased UUAE was an independent risk factor for DR but not for lower limb atherosclerosis in hospitalized Chinese patients with type 2 diabetes. In selected populations, such as those with type 2 diabetes, the role of uric acid in atherosclerosis may be result from other concomitantly atherosclerotic risk factors, such as DR.

Decreased urine uric acid excretion is an independent risk factor for chronic kidney disease but not for carotid atherosclerosis in hospital-based patients with type 2 diabetes: a cross-sectional study

Background

The associations between urine uric acid excretion (UUAE) and chronic kidney disease (CKD)/atherosclerosis have not been investigated. Our aims were to investigate the relationships between UUAE and CKD and carotid atherosclerotic lesions in hospitalized Chinese patients with type 2 diabetes.

Methods

This was a cross-sectional study that was conducted with 2627 Chinese inpatients with type 2 diabetes. UUAE was determined enzymatically using a single 24-h urine collection. The subjects were stratified into quartiles according to their UUAE levels. Carotid atherosclerotic lesions, including carotid intima-media thickness (CIMT), plaque and stenosis, were assessed by Doppler ultrasound. Both CKD and carotid atherosclerotic lesions were compared between the UUAE quartile groups.

Results

After adjustment for confounding factors, there was a significant decrease in the prevalence of CKD in the patients with type 2 diabetes across the UUAE quartiles (16.9%, 8.5%, 5.9%, and 4.9%; p < 0.001). Multiple logistic regression analyses revealed that the UUAE quartiles were significantly and inversely associated with the presence of CKD (p < 0.001). Compared with the diabetics in the highest UUAE quartile, those in the lowest quartile exhibited a nearly 4.2-fold increase in the risk of CKD (95% CI: 2.272-7.568; p < 0.001). The CIMT value (0.91 ± 0.22 mm for the diabetics with CKD and 0.82 ± 0.20 mm for the diabetics without CKD, p = 0.001) and the prevalence of carotid plaques (62.1% for the diabetics with CKD and 41.8% for the diabetics without CKD, p = 0.025) were significantly higher in the diabetics with CKD than in those without CKD. However, there was no obvious difference in carotid atherosclerotic lesions across the UUAE quartiles after controlling for the confounding factors.

Conclusions

Decreased UUAE was closely associated with the presence of CKD but not with carotid atherosclerotic lesions in hospitalized Chinese patients with type 2 diabetes. Our results suggest that UUAE is an independent risk factor for CKD in type 2 diabetes. In selected populations, such as patient with type 2 diabetes, the role of uric acid in atherosclerosis might be the result of other concomitant atherosclerotic risk factors, such as CKD.

Impact of the Serum Uric Acid Level on Subclinical Atherosclerosis in Middle-aged and Elderly Chinese

AIM

The carotid intima-media thickness (CIMT) is now validated as a sensitive marker of atherosclerosis and is directly associated with an increased risk of cardiovascular disease. Considering that the independent association between the serum uric acid level and CIMT remains controversial due to the complex interrelationship with other known cardiovascular risk factors, further studies are needed. The aim of the present study is to explore the association between the serum uric acid level and CIMT in a general Chinese population and determine whether the association differs according to varied metabolic status.

METHODS

The present study was cross-sectional in design. A total of 10,281 community-based participants 40 years of age or older from Shanghai, China were included in the current analysis. All participants underwent a detailed questionnaire interview, anthropometric measurements and ultrasonography to assess the CIMT. Blood and urine samples were collected for the biochemical measurements.

RESULTS

The serum uric acid levels were positively associated with obesity- and diabetes-related parameters and the CIMT. In a logistic regression model controlling for potential confounders, compared with the participants in the first quartile of the uric acid level, those in the fourth quartile had a higher odds of an elevated CIMT in both men (odds ratio [OR]=1.37; 95% confidence interval [CI]=1.07-1.75) and women (OR=1.48; 95% CI=1.12-1.94). The subgroup analyses revealed that an association between an elevated CIMT and the serum uric acid level persisted regardless of diuretic use and the hypertension, diabetes mellitus and chronic kidney disease status. However, the association disappeared in the patients who consumed alcohol and in premenopausal women.

CONCLUSIONS

The serum uric acid level is positively associated with an elevated CIMT in middle-aged and elderly Chinese subjects, independent of known risk determinants of cardiovascular disease.

The Effects of Allopurinol on the Carotid Intima-media Thickness in Patients with Type 2 Diabetes and Asymptomatic Hyperuricemia: A Three-year Randomized Parallel-controlled Study

OBJECTIVE

The aim of this study was to investigate the long-term effective control of serum uric acid by allopurinol on the carotid intima-media thickness (IMT) in patients with type 2 diabetes (T2DM) and asymptomatic hyperuricemia (HUA).

METHODS

This was a randomized open parallel-controlled study. In this study, 176 patients with T2DM and asymptomatic HUA were randomly allocated to the conventional or allopurinol treatment groups on the basis of a computer-generated random number table. Changes in the carotid IMT, biochemical indexes, high sensitive C-reactive protein (hs-CRP) and the incidence of hypertension in patients before and after three years of treatment were examined and compared between the groups.

RESULTS

There were no statistically significant differences in the baseline characteristics of the study participants between the two treatment groups (p>0.05 for all). Nevertheless, the serum uric acid, triglyceride, and hs-CRP levels and the homeostasis assessment for insulin resistance (HOMA-IR), systolic blood pressure, diastolic blood pressure and the carotid IMT in the allopurinol group were significantly lower than those in the conventional group after three years of treatment (p<0.01 for all). The intention-to-treat analysis indicated that the incidence of new-onset hypertension in the allopurinol group showed a declining trend compared to that in the conventional treatment group (6.8% vs. 13.6%, p>0.05).

CONCLUSION

The long-term effective control of serum uric acid by allopurinol may improve insulin resistance, decrease the serum levels of hs-CRP, reduce the carotid IMT, and may delay the development of atherosclerosis in patients with T2DM and asymptomatic HUA.

Effects of uric acid on hearts of rats with chronic kidney disease

AIMS

To study the effects of uric acid on cardiac lesions and its possible mechanism by establishing an early-stage CKD animal model with hyperuricemia. Allopurinol was used to see whether it could reduce cardiac lesions.

METHODS

The experimental rats were randomly divided into 4 groups (n = 15): Group A (sham-operative group), Group B (CKD group), Group C (CKD with hyperuricemia group), Group D (CKD with hyperuricemia + allopurinol group). After 16 weeks, the rats were sacrificed and blood samples were collected for detection of Scr, SUA, hs-CRP and IL-6. Kidney and heart tissues were pathologically examined. The collagen I of heart tissues was examined by immunohistochemistrical methods.

RESULTS

Obvious pathological changes could be observed in Group C. However, compared to Group C, the pathological changes in Group D were lighter. The proportion of collagen I positive area (PCIPA) in Group C was significantly higher than that in Group A, B and D. Univariate analysis showed that the SUA level had a significant positive correlation with PCIPA in myocardium. IL-6 and hs-CRP levels in Group C were significantly higher than in Group A, B and D. Univariate analysis showed that the SUA level had a significant positive correlation with IL-6 and hs-CRP, and PCIPA in myocardium had a significant positive correlation with hs-CRP and IL-6 levels.

CONCLUSIONS

There were obvious cardiac lesions in early-stage CKD rats with hyperuricemia, and the severity of cardiac lesions was positively related to the level of SUA. Micro-inflammation might be one mechanism causing cardiac lesions. Allopurinol could alleviate cardiac lesions in early-stage CKD rats by lowering the SUA level, which, in turn, could reduce the severity of micro-inflammation.

Correlation between serum uric Acid and renal function in patients with stable coronary artery disease and type 2 diabetes

Background

The aim of this study was to investigate the relationship between serum uric acid and renal function, expressed as estimated glomerular filtration rate (eGFR), in patients with stable coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM) in China.

Methods

Serum levels of uric acid and creatinine were determined in 526 enrolled patients diagnosed with stable CAD and T2DM. To assess renal function, eGFR was calculated using a modified MDRD formula suitable for the Chinese population. Patients’ anthropometric measurements were collected using standardized protocols, and 6-month follow-up results were collected and analyzed. Pearson’s correlation coefficient r was calculated and multivariate analysis was performed to evaluate the relationship between uric acid and renal function. Patients with eGFR < 60 mL/min/1.73 m² were classified as having reduced renal function or chronic kidney disease (CKD) in this study.

Results

Uric acid levels were negatively associated with eGFR (P = 0.002), especially in patients with CKD (eGFR < 60 mL/min/1.73 m²) (P < 0.001). In patients with reduced renal function, the risk in the highest quartile of uric acid levels was higher than in the lowest quartile (odds ratio 9.18, 95% confidence interval: 4.01 - 21.01, P < 0.001). These associations remained after multiple adjustments for potential confounders and were recapitulated after 6-month follow-up.

Conclusions

Serum uric acid level is negatively associated with renal function, as assessed by eGFR, and serves as an independent predictor for CKD in patients with stable CAD and T2DM.

Serum uric acid and its relationship with metabolic syndrome and cardiovascular risk profile in patients with hypertension: insights from the I-DEMAND study

BACKGROUND AND AIMS

The independent role of serum uric acid (SUA) as a marker of cardio-renal risk is debated. The aim of this study was to assess the relationship between SUA, metabolic syndrome (MS), and other cardiovascular (CV) risk factors in an Italian population of hypertensive patients with a high prevalence of diabetes.

METHODS AND RESULTS

A total of 2429 patients (mean age 62 ± 11 years) among those enrolled in the I-DEMAND study were stratified on the basis of SUA gender specific quartiles. MS was defined according to the NCEP-ATP III criteria, chronic kidney disease (CKD) as an estimated GFR (CKD-Epi) <60 ml/min/1.73 m(2) or as the presence of microalbuminuria (albumin-to-creatinine ratio ≥2.5 mg/mmol in men and ≥3.5 mg/mmol in women). The prevalence of MS, CKD, and positive history for CV events was 72%, 43%, and 20%, respectively. SUA levels correlated with the presence of MS, its components, signs of renal damage and worse CV risk profile. Multivariate logistic regression analysis revealed that SUA was associated with a positive history of CV events and high Framingham risk score even after adjusting for MS and its components (OR 1.10, 95% CI 1.03-1.18; P = 0.0060; OR 1.28, 95% CI 1.15-1.42; P < 0.0001). These associations were stronger in patients without diabetes and with normal renal function.

CONCLUSIONS

Mild hyperuricemia is a strong, independent marker of MS and high cardio-renal risk profile in hypertensive patients under specialist care. Intervention trials are needed to investigate whether the reduction of SUA levels favorably impacts outcome in patients at high CV risk.

Association between serum uric acid, hypertension, vascular stiffness and subclinical atherosclerosis: data from the Brisighella Heart Study

OBJECTIVE

Serum uric acid (SUA) levels correlate with many recognized cardiovascular risk factors, including age, male sex, hypertension, diabetes mellitus, hypertriglyceridemia, obesity, and insulin resistance. The aim of our study was to verify in a large well characterized population sample the relationship between SUA values, hypertension, arterial stiffness and subclinical atherosclerosis.

METHODS

For this study, we selected 248 men and 371 women adult patients enrolled in the last Brisighella Heart Study population survey for which a full set of data were available and not consuming antihypertensive, antidiabetic, lipid-lowering and uric acid-lowering drugs. SUA and other available variables were related to blood pressure level, carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (cIMT).

RESULTS

Hypertension prevalence was strongly related to SUA quartiles: we found significant differences between the 2nd (23.0%) and the 3rd quartiles (36.4%; P vs. 2nd < 0.05), and between the 3rd and the 4th quartile (56.3%; P vs. 3rd < 0.05). Similarly, the metabolic syndrome prevalence increased significantly at 39.5% in the 3rd SUA quartile (P < 0.05 vs. 2nd) and at 58.9% in the 4th quartile (P < 0.05 vs. 3rd). Intima-media thickness gradually and significantly rose along quartiles of SUA (P for trend < 0.0001), in particular, it was 0.86  mm in the 1st quartile, 0.90 in the 2nd, 0.94 in the 3rd, and 0.97 in the last quartile, with significant differences between each quartiles (all P < 0.05). In multivariate regression analyses, SUA resulted to be significantly associated to hypertension and metabolic syndrome prevalence, and IMT. Even if a significant association between SUA and cfPWV was found in univariate analysis (P = 0.002), when adjusting for age, the trend became nonsignificant (0.20).

CONCLUSION

In the studied population sample, after adjustment for a large number of parameters, SUA appears to be significantly correlated to hypertension and IMT, but not to aortic stiffness.

The cross-sectional association between uric acid and atherosclerosis and the role of low-grade inflammation: the CODAM study

OBJECTIVES

The aims of this study were to investigate (i) associations between uric acid and prevalent cardiovascular disease (CVD), ankle-arm blood pressure index (AAIx) and carotid intima-media thickness (CIMT) in the total population and in predefined subgroups according to glucose metabolism status and (ii) the extent to which these associations are explained by low-grade inflammation.

METHODS

Cross-sectional analyses were conducted among 530 individuals [60.6% men, mean age 58.9 years (s.d. 6.9), 52.6% normal glucose metabolism (NGM)] at increased risk of CVD from the Cohort of Diabetes and Atherosclerosis Maastricht study. A low-grade inflammation score was computed by averaging the z-scores of eight inflammation markers [CRP, TNF-α, IL-6, IL-8, serum amyloid A, intercellular adhesion molecule 1 (ICAM-1), ceruloplasmin and haptoglobin].

RESULTS

After adjustment for traditional CVD risk factors, plasma uric acid (per s.d. of 81 μmol/l) was associated with CVD in individuals with NGM [odds ratio (OR) = 1.66, 95% CI 1.06, 2.58] but not with disturbed glucose metabolism (DGM) (OR = 0.81, 95% CI 0.55, 1.19, P interaction = 0.165). Uric acid was associated with CIMT in the total population (β = 0.024, 95% CI 0.007, 0.042) and slightly more strongly in individuals with NGM (β = 0.030, 95% CI 0.006, 0.054) than DGM (β = 0.018, 95% CI -0.009, 0.044, P interaction = 0.443). There was no association between uric acid and AAIx in any group (P interaction = 0.058). Uric acid was associated with low-grade inflammation in the total population (β = 0.074, 95% CI 0.013, 0.134, P interaction = 0.737). Adding low-grade inflammation to the models did not attenuate any of the associations.

CONCLUSION

The associations for uric acid with CIMT, and with CVD in NGM only, were not explained by low-grade inflammation. A difference in the strength of the associations between individuals with NGM and DGM was suggested.

A Comparative Study of Serum Uric Acid levels and Lipid Ratios in Coronary Artery Disease Patients

INTRODUCTION

Coronary Artery Disease (CAD) appears to be common in the Indian population of different geographical origins, religions and languages. Measurement of lipid fractions and ratios are widely recommended for risk assessment. A few studies have shown that serum uric acid plays a role in the development of cardiovascular morbidity. Very few reports are cited linking serum uric acid with the lipid fraction in CAD.

OBJECTIVES

To find the significance of non-HDL cholesterol, LDL-c/HDL-c ratio, TC/HDL ratio and serum uric acid level in CAD patients.

SUBJECTS AND METHODOLOGY

In this study, we included fifty CAD patients as subjects and an equal number of controls. Both subjects and controls were assessed for anthropometric, physiological and biochemical parameters.

RESULTS

The present study showed significant increased levels of total cholesterol (p=0.002), TAGs (p<0.001), HDL (p=0.005), LDL (p<0.006) and non-HDL cholesterol (p<0.001). LDL-c/HDL-c ratio (p<0.001) and TC/HDL ratio (p<0.001) in CAD patients (subjects) were also significant when compared to controls. Uric acid level in CAD patients was increased (p<0.001).

CONCLUSION

Serum Uric Acid, TC/HDL and LDL/HDL ratios could be regarded as objective markers, in association with existing atherogenic dyslipidemia in patients with CAD.

Gout patients have an increased risk of developing most cancers, especially urological cancers

OBJECTIVES

Inflammation and hyperuricaemia, which are the major characteristics of gout disease, are thought to be associated with carcinogenesis and anti-carcinogenesis, respectively. Therefore, we aimed to explore the causal effect on cancers from those with gout disease.

METHOD

New gout patients without a history of cancer were included from 1998 to 2000, and they had been followed up from 2001 to 2008 to observe the incidence of cancers from national outpatient records in Taiwan.

RESULTS

A total of 8408 male gout patients and 25,010 male controls were included by matching gout patients' age and year and month of first diagnosis during the including period. The mean ages at diagnosis were 51.03 ± 14.52 and 50.90 ± 14.45 years for gout patients and controls, respectively. The overall incidence of all cancers was 9.82 cases per 1000 person-years among gout patients compared to 4.35 cases per 1000 person-years among controls after 8 years of follow-up. The age-adjusted standardized incidence ratios (SIRs) were 2.26 [95% confidence interval (CI) 2.06-2.49], 3.31 (95% CI 2.55-4.31), 3.14 (95% CI 2.12-4.64), and 2.18 (95% CI 1.34-3.56) for all cancers, prostate cancer, bladder cancer, and renal cancer, respectively. The cumulative hazard ratios (HRs) were significantly higher in gout patients than in controls with regard to developing prostate, bladder, and renal cancers (all p < 0.001).

CONCLUSIONS

This study shows that gout patients are more likely to develop most cancers, especially the urological cancers: prostate, bladder, and renal cancers. The data also support the hypothesis of a link between metabolic syndrome (MetS) and cancer disorders.

Serum uric acid is associated with arterial stiffness in men with newly diagnosed type 2 diabetes mellitus

BACKGROUND

Increased serum uric acid levels and vascular atherosclerosis are very common in diabetes. However, few studies focused on the relationship between serum uric acid and aortic or peripheral arterial stiffness in newly diagnosed diabetic patients. This study investigated the association between serum uric acid levels and carotid-femoral pulse wave velocity (cfPWV) or carotid-radial (cr) PWV in male patients with newly diagnosed type 2 diabetes mellitus (T2DM).

METHODS

106 male patients with newly diagnosed T2DM were recruited. cfPWV and crPWV as well as anthropometric parameters, blood pressure, serum uric acid, blood glucose, fasting insulin, C-reactive protein and blood lipids were measured.

RESULTS

The subjects were divided into low uric acid (UA) subgroup and high UA subgroup according to uric acid median. cfPWV and crPWV were significantly higher in high UA subgroup. Serum uric acid significantly correlated with cfPWV (r = 0.533, P < 0.001), crPWV (r = 0.334, P = 0.001), waist circumference (r = 0.350, P < 0.001), waist-to-hip ratio (r = 0.254, P = 0.009), fasting insulin (r = 0.432, P < 0.001), HOMA-IR (r = 0.173, P = 0.042), fasting blood glucose (r = -0.271, P = 0.005), haemoglobin A1c (r = -0.202, P = 0.038), and HDL-cholesterol (r = -0.267, P = 0.006) after correction for age. Stepwise multiple regressions showed that the independent determinants of cfPWV were serum uric acid, age, C-reactive protein, HDL-cholesterol, and smoking status. And the independent determinants of crPWV were serum uric acid, age, diastolic blood pressure, and HDL-cholesterol.

CONCLUSIONS

Serum uric acid is significantly associated with increased aortic and peripheral arterial stiffness in men with T2DM at the early stage.

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

Background

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

Methods and Results

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

Conclusions

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

Association between serum uric acid levels and cardiovascular disease in middle-aged and elderly Chinese individuals

BACKGROUND

A link between uric acid (UA) levels and cardiovascular diseases has been previously reported. However, its importance as a risk factor is still controversial. This study sought to determine whether elevated serum uric acid levels are associated with cardiovascular disease (CVD) in middle-aged and elderly Chinese individuals.

METHODS

We conducted a population-based cross-sectional study in Shanghai, with a total of 8510 participants aged ≥40 years. The CVD included diagnosed coronary heart disease (CHD) and stroke. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans.

RESULTS

Uric acid levels were positively associated with BMI, waist circumference, triglycerides, systolic blood pressure, diastolic blood pressure, glycohemoglobin, fasting plasma glucose, postprandial 2-hour plasma glucose (all P < 0.05), and negatively associated with HDL-cholesterol (P < 0.001). The prevalence of CVD significantly increased with increasing quartiles of UA in those without MetS group (p trend < 0.001), but not necessarily increased in those with MetS. After adjustment for metabolic syndrome and other cardiovascular risk factors, multivariate logistic regression analysis showed that odds ratios (OR) for CHD, stroke, and CVD in those in the fourth quartiles were 2.34 (95% confidence interval [CI] 1.73 to 3.45), 2.18 (95% CI 1.86 to 3.28), and 2.16 (95% CI 1.80 to 3.29), respectively, compared with those in the first quartile of UA.

CONCLUSIONS

Elevated serum uric acid level was associated with CVD, independent of conventional cardiovascular disease risk factors and metabolic syndrome.

Association of lipid profiles and the ratios with arterial stiffness in middle-aged and elderly Chinese

Background

Serum lipids and the ratios are known to be associated with the cardiovascular diseases (CVD). However, the associations of serum lipids and the ratios related to arterial stiffness are unclear. We sought to compare the strength of these serum lipids and the ratios with arterial stiffness assessing by brachial-ankle pulse wave velocity (baPWV) in the middle-aged and elderly Chinese subjects.

Methods

A total number of 1133 Chinese aged from 50 to 90 years old were recruited from Shanghai downtown district. The serum lipids, baPWV and major cardiovascular risk factors of the participants were measured.

Results

Participants with high baPWV exhibited higher levels of non-HDL-c, TC/HDL-c, TG/HDL-c, LDL-c/HDL-c, and non-HDL-c/HDL-c, while HDL-c worked in the opposite direction (all P<0.05). In addition, TC, TG, LDL-c, non-HDL-c, TC/HDL-c, TG/HDL-c, LDL-c/HDL-c, and non-HDL-c/HDL-c had a positive relationship with the baPWV value, while HDL-c was on the contrary (all P <0.05). Finally, individuals with high non-HDL-c/HDL-c (OR 1.71, 95% CI 1.06-2.55, P = 0.013) and low HDL-c (OR 0.57, 95% CI 0.35-0.96, P = 0.024) were seem to be at high risk of arterial stiffness.

Conclusions

As a risk indicator, non-HDL-c/HDL-c, which could be readily obtained from routine serum lipids, was significantly associated with baPWV. Non-HDL-c/HDL-c was superior to traditional lipid variables for estimating arterial stiffness in the middle-aged and elderly Chinese population.

Comorbidities in patients with crystal diseases and hyperuricemia

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

Review of hyperuricemia as new marker for metabolic syndrome

Hyperuricemia has long been established as the major etiologic factor in gout. In recent years, a large body of evidence has accumulated that suggests that hyperuricemia may play a role in the development and pathogenesis of a number of metabolic, hemodynamic, and systemic pathologic diseases, including metabolic syndrome, hypertension, stroke, and atherosclerosis. A number of epidemiologic studies have linked hyperuricemia with each of these disorders. In some studies, therapies that lower uric acid may prevent or improve certain components of the metabolic syndrome. There is an association between uric acid and the development of systemic lupus erythematosus; the connection between other rheumatic diseases such as rheumatoid arthritis and osteoarthritis is less clear. The mechanism for the role of uric acid in disorders other than gout is not well established but recent investigations point towards systemic inflammation induced by urate, as the major pathophysiological event common to systemic diseases, including atherosclerosis.

Prevalence of hyperuricemia and the relationship between serum uric acid and metabolic syndrome in the Asian Mongolian area

AIM

To investigate the prevalence of hyperuricemia and the association between the serum uric aci (SUA) levels and incidence of metabolic syndrome (MetS) in the Mongolian area of China.

METHODS

This cross-sectional survey was based on a population of 1,426 subjects (809 men and 617 women) 20-80 years of age who were recruited from Inner Mongolia, China. Metabolic and anthropometric indicators were measured according to standard methods. Hyperuricemia was defined as an SUA level of ≥7.0 mg/dL for men and ≥6.0 mg/dL for women. MetS was diagnosed based on the consensus criteria released in 2009 from a joint collaboration organization.

RESULTS

The prevalence of hyperuricemia was 17.7% in men and 5.2% in women. The prevalence of MetS in men was higher than that observed in women(36.7% vs. 17.8%). Waist circumference, BMI and the level of triglycerides were most strongly correlated with the SUA level in both sexes. Men with hyperuricemia had an increased risk of MetS [OR(95%CI)=2.95(2.00-4.35)], while men with a "normal" SUA level(＞5.0 mg/dL and ＜6.3 mg/dL) had a higher risk of MetS, central obesity and hypertriglyceridemia than men in the lower level group (≤5 mg/dL). Women with a higher SUA level(≥4.3 mg/dL) had an increased risk of MetS, central obesity, hypertriglyceridemia and hypertension compared with women in the lowest tertile SUA group (≤3.5 mg/dL).

CONCLUSIONS

The SUA level is significantly associated with various metabolic indicators. In this study, waist circumference and the level of triglycerides were most strongly correlated with the SUA level in both sexes. Individuals with a normal level of SUA had an increased risk of MetS and other metabolic disorders. Further research on appropriate cut-off values for pre-hyperuricemia is expected, and the early detection of hyperuricemia is essential for the prevention of MetS.

Emergent biomarkers of residual cardiovascular risk in patients with low HDL-c and/or high triglycerides and average LDL-c concentrations: focus on HDL subpopulations, Oxidized LDL, adiponectin, and uric acid

This study intended to determine the impact of HDL-c and/or TGs levels on patients with average LDL-c concentration, focusing on lipidic, oxidative, inflammatory, and angiogenic profiles. Patients with cardiovascular risk factors (n = 169) were divided into 4 subgroups, combining normal and low HDL-c with normal and high TGs patients. The following data was analyzed: BP, BMI, waist circumference and serum glucose, Total-c, TGs, LDL-c, oxidized-LDL, total HDL-c and HDL subpopulations, paraoxonase-1 (PON1) activity, hsCRP, uric acid, TNF- α , adiponectin, VEGF, and iCAM1. The two populations with increased TGs levels, regardless of the normal or low HDL-c, presented obesity and higher waist circumference, Total-c, LDL-c, Ox-LDL, and uric acid. Adiponectin concentration was significantly lower and VEGF was higher in the population with cumulative low values of HDL-c and high values of TGs, while HDL quality was reduced in the populations with impaired values of HDL-c and/or TGs, viewed by reduced large and increased small HDL subfractions. In conclusion, in a population with cardiovascular risk factors, low HDL-c and/or high TGs concentrations seem to be associated with a poor cardiometabolic profile, despite average LDL-c levels. This condition, often called residual risk, is better evidenced by using both traditional and nontraditional CV biomarkers, including large and small HDL subfractions, Ox-LDL, adiponectin, VEGF, and uric acid.

The relevance of hyperuricemia and metabolic syndrome and the effect of blood lead level on uric Acid concentration in steelmaking workers

Objectives

Uric acid concentration is known to increase the prevalence of metabolic syndrome by affecting its components, resulting in increased risk of cerebrovascular and cardiovascular diseases, and long-term lead exposure is known to affect this serum uric acid level. In this study, we aimed to examine the association between the causes of hyperuricemia and metabolic syndrome, and to determine whether an increased blood lead level affects hyperuricemia.

Method

Anthropometric measurements, surveys, and blood tests were conducted between May and June 2012 in 759 men working in the steelmaking process at a domestic steel company. Workers were divided into 2 groups according to the presence or absence of hyperuricemia, and an analysis was performed to examine its association with metabolic syndrome. In addition, the workers were divided into 3 groups according to the blood lead level to analyze the association between blood lead and hyperuricemia.

Results

The geometric mean (standard deviation) of the blood lead levels in the hyperuricemia group was significantly higher than that of the healthy group (3.8 [1.8] vs. 3.3 [1.8] μg/dL). The adjusted odds ratio for metabolic syndrome of the hyperuricemia group increased significantly to 1.787 (1.125–2.839) compared with the healthy group. In addition, the adjusted odds ratios for the occurrence of hyperuricemia in the tertile 2 (2.61–4.50 μg/dL) and tertile 3 groups (>4.50 μg/dL) according to blood lead level significantly increased to 1.763 (1.116–2.784) and 1.982 (1.254–3.132), respectively, compared with the tertile 1 group (< 2.61 μg/dL).

Conclusion

Hyperuricemia is believed to function as an independent risk factor for metabolic syndrome, while lead seems to increase the serum uric acid level even at a considerably low blood level. Therefore, attention should be given to patients with hyperuricemia and metabolic syndrome who are prone to lead exposure, and a prospective study should be conducted to identify their causal relationship.

Metabolic syndrome, diabetes, and hyperuricemia

PURPOSE OF REVIEW

To explore the causal relationship between metabolic syndrome, type 2 diabetes and hyperuricemia.

RECENT FINDINGS

The prevalence of hyperuricemia in male adults with metabolic syndrome was increased and a large difference in prevalence of metabolic syndrome also existed in those with hyperuricemia compared with normouricemia. Even in those with normouricemia, higher serum uric acid levels were associated with metabolic syndrome. Serum uric acid was an independent risk factor for incident diabetes, and evidence showed that the patients with both gout and type 2 diabetes exhibited a mutual inter-dependent effect on higher incidences. Furthermore, obese patients often demonstrated insulin resistance and adipose tissue macrophage with low-grade inflammation, which is suggested to be the major contributor. Although alcohol intake is considered a risk for developing hyperuricemia, moderate alcohol intake showed a lower risk for developing type 2 diabetes and insulin resistance. Hyperinsulinemia reduces renal excretion of uric acid on the proximal tubular of the kidney leading to hyperuricemia, which has deleterious effects on endothelial function and on nitric oxide bioavailability, thus causing hyperinsulinemia.

SUMMARY

We found evidence to suggest that insulin resistance plays a potentially key role in the causal relationship between metabolic syndrome, type 2 diabetes and hyperuricemia. Furthermore, it is likely that hyperuricemia and insulin resistance share a bidirectional causal effect.

The liver and the kidney: two critical organs influencing the atherothrombotic risk in metabolic syndrome

The increased atherothrombotic risk in patients with metabolic syndrome (MetS) has been classically explained by the multiplicative effect of systemic concomitant pro-atherosclerotic factors. In particular, centripetal obesity, dyslipidaemia, glucose intolerance, hypertension (differently combined in the diagnosis of the disease) would be expected to act as classical cardiovascular risk conditions underlying accelerated atherogenesis. In order to better understand specific atherosclerotic pathophysiology in MetS, emerging evidence focused on the alterations in different organs that could serve as both pathophysiological targets and active players in the disease. Abnormalities in adipose tissue, heart and arteries have been widely investigated in a variety of basic research and clinical studies in MetS. In this narrative review, we focus on pathophysiological activities of the liver and kidney. Considering its key role in metabolism and production of soluble inflammatory mediators (such as C-reactive protein [CRP]), the liver in MetS has been shown to be altered both in its structure and function. In particular, a relevant amount of the fat accumulated within this organ has been shown to be associated with different degrees of inflammation and potential insulin resistance. In humans, non-alcoholic fatty liver disease (NAFLD) has been described as the hepatic manifestation of MetS. In an analogous manner, epidemiological evidence strongly suggested a "guilty" association between MetS and chronic kidney disease (CKD). Some biomarkers of hepatic (such as C-reactive protein, TNF-alpha or other cytokines) and renal diseases (such as uric acid) associated with MetS might be particularly useful to better manage and prevent the atherothrombotic risk.

Diabetes abrogates sex differences and aggravates cardiometabolic risk in postmenopausal women

Background

The aim of this study is to evaluate the effect of gender and menopause in cardiometabolic risk in a type 2 diabetes mellitus (T2DM) population, based on classical and non-traditional markers.

Methods

Seventy four volunteers and 110 T2DM patients were enrolled in the study. Anthropometric data, blood pressure, body mass index (BMI), waist circumference (WC) and the following serum markers were analyzed: glucose, Total-c, TGs, LDL-c, Oxidized-LDL, total HDL-c and large and small HDL-c subpopulations, paraoxonase 1 activity, hsCRP, uric acid, TNF-α, adiponectin and VEGF.

Results

Non-diabetic women, compared to men, presented lower glycemia, WC, small HDL-c, uric acid, TNF-α and increased large HDL-c. Diabetes abrogates the protective effect of female gender, since diabetic women showed increased BMI, WC, small HDL-c, VEGF, uric acid, TNF-α and hsCRP, as well as reduced adiponectin, when compared with non-diabetic. In diabetic females, but not in males, WC is directly and significantly associated with TNF-α, VEGF, hsCRP and uric acid; TNF-α is directly associated with VEGF and hsCRP, and inversely with adiponectin. Postmenopausal females presented a worsen cardiometabolic profile, viewed by the increased WC, small HDL-c, VEGF, uric acid, TNF-α and hsCRP. In this population, WC is directly and significantly associated with TNF-α, VEGF, hsCRP; TNF-α is directly associated with VEGF; and uric acid is inversely associated with large HDL-c and hsCRP with adiponectin, also inversely.

Conclusions

Diabetes abrogates the protective effect of gender on non-diabetic women, and postmenopausal diabetic females presented worsen cardiometabolic risk, including a more atherogenic lipid sketch and a pro-inflammatory and pro-angiogenic profile. The classical cardiovascular risk factors (CVRFs) fail to completely explain these differences, which are better clarified using “non-traditional” factors, such as HDL-c subpopulations, rather than total HDL-c content, and markers of inflammation and angiogenesis, namely TNF-α, hsCRP, uric acid and VEGF. Multi-therapeutic intervention, directed to obesity, atherogenic lipid particles and inflammatory mediators is advisory in order to efficiently prevent the serious diabetic cardiovascular complications.

Serum osteocalcin level and its association with carotid atherosclerosis in patients with type 2 diabetes

Objective

To investigate the association of serum osteocalcin with carotid atherosclerosis in patients with type 2 diabetes.

Methods

We performed a cross-sectional community-based study in metropolitan area. Serum total osteocalcin was measured by radioimmunoassay in 382 men and 435 postmenopausal women. The carotid artery intima-media thickness (IMT) and carotid plaques (PLQ) were measured by B-mode ultrasound.

Results

The crude mean of serum osteocalcin concentrations were 4.52±2.43 ng/ml for men and 5.75±2.92 ng/ml for postmenopausal women (P <0.001), respectively. Osteocalcin levels were associated inversely with age, fasting serum insulin, HOMA-IR, ALT, triglycerides, total cholesterol, LDL- cholesterol, CRP (all P<0.001) and positively with adiponectin and HOMA-B (all P<0.05). After multiple adjustment, the odds ratios (ORs) were substantially higher risk for carotid plaques (OR 1.77 for 1 SD decrease in osteocalcin, 95% CI 1.23-2.76, p=0.005). These associations remained significant after further adjustment for potential confounder.

Conclusions

Serum osteocalcin levels is an independent risk factor for carotid atherosclerosis in patients with type 2 diabetes.

Contribution of uric acid to cancer risk, recurrence, and mortality

Two risk factors for the development and progression of cancers that are amenable to life style modification are chronic inflammation and the metabolic syndrome. This review proposes two new targets that may mechanistically integrate inflammation and metabolic syndrome, have been largely ignored, and are known to be druggable. Recent evidence has demonstrated that elevated serum uric acid (hyperuricemia) is associated with excess cancer risk, recurrence, and mortality. Although uric acid (UA) can function as a systemic antioxidant, its pro-inflammatory properties have been postulated to play an important role in the pathogenesis of cancer. Furthermore, obesity, Type 2 Diabetes Mellitus (T2DM), and the metabolic syndrome (MetS) are also associated with excess cancer, chronic inflammation, and with hyperuricemia, suggesting that UA may represent an important link between these disorders and the development of cancer. While pharmacological modulation of hyperuricemia could in principal augment anti-cancer therapeutic strategies, some cancer cells express low intracellular levels of the enzyme Xanthine Oxidoreductase (XOR) that are associated with increased cancer aggressiveness and poor clinical outcome. Thus, systemic pharmacological inhibition of XOR may worsen clinical outcome, and specific strategies that target serum uric acid (SUA) without inhibiting tumor cell XOR may create new therapeutic opportunities for cancer associated with hyperuricemia. This review will summarize the evidence that elevated SUA may be a true risk factor for cancer incidence and mortality, and mechanisms by which UA may contribute to cancer pathogenesis will be discussed in the hope that these will identify new opportunities for cancer management.

Gender difference in carotid intima-media thickness in type 2 diabetic patients: a 4-year follow-up study

Background

Different population studies have reported gender difference in carotid intima-media thickness (CIMT), which is proved to be a risk factor of cardiovascular diseases. However, few longitudinal researches examine this gender difference in type 2 diabetes mellitus (T2DM) patients. Therefore, we prospectively analyzed CIMT in T2DM patients over a 4-year follow-up period.

Methods

355 T2DM patients (mean age 59 years; 54.9% women) were included in the present study. CIMT were measured using Color Doppler ultrasound. CIMT was measured at baseline (CIMT) in 2006 and at follow-up in 2010. Biochemical and clinical measurements were collected at baseline.

Results

Mean value of CIMT1 and CIMT2 were 0.740 ± 0.148 mm and 0.842 ± 0.179 mm, respectively. Men had higher CIMT than women both at baseline and at follow-up (CIMT1: 0.762 ± 0.149 vs 0.723 ± 0.146 mm, P = 0.0149; CIMT2: 0.880 ± 0.189 vs 0.810 ± 0.164 mm, P = 0.0002). Mean annual progression of CIMT (dCIMT) was 0.025 ± 0.022 mm/year. dCIMT was larger in men than in women (0.030 ± 0.025 vs 0.022 ± 0.019 mm, P = 0.0006). In multiple regression analyses, age was an independent risk factor of CIMT in both genders, while dCIMT was associated with age only in men.

Conclusions

Gender difference in CIMT was confirmed in T2DM patients. Moreover, impact of ageing on CIMT progression only existed in men, which might be the reason that gender difference in CIMT increased with age.

The effects of mammalian target of rapamycin inhibitors on serum uric acid levels in renal transplant patients

BACKGROUNDS/AIMS

Elevated uric acid (UA) levels are frequently observed after renal transplantation. We investigated the consequences of shifting from calcineurin inhibitors (CNI) to mammalian target of rapamycin inhibitors (mTORi) on UA levels and graft functions.

METHODS

Ninety-six patients were enrolled. Main points of interest were changes in UA and glomerular filtration rate (GFR).

RESULTS

Mean age of the whole population was 39 ± 11 years (18-73), and 64.2 % were male. Patients were stratified into two groups according to their CNI type prior to the switch as cyclosporin A (CsA) or tacrolimus (Tac). Patients that were switched from CsA had a mean GFR of 49 ± 18 ml/min and serum UA level of 7.4 ± 1.8 mg/dl at the pre-switch period. Mean GFR increased to 53 ± 22 ml/min (p = 0.03), and UA levels decreased to 6.2 ± 1.6 mg/dl at the final visit (p < 0.001). In the Tac group, pre-switch mean GFR was 59 ± 28 ml/min and serum UA level 6.6 ± 2.6 mg/dl. In this group, mean GFR increased to 63 ± 28 ml/min (p = 0.03) and UA levels decreased to 6.2 ± 2.1 at the last visit (p < 0.001).

CONCLUSION

Switch from CNI to mTORi-based regimen provides better control of UA levels and improves renal functions.

The metabolic syndrome and progression of carotid atherosclerosis over 13 years. The Tromsø study

Background

The metabolic syndrome (MetS) is associated with increased risk of cardiovascular disease. In this study, we examine if metabolic syndrome predicts progression of atherosclerosis over 13 years.

Methods

Participants were 1442 men and 1532 women in the population-based Tromsø Study who underwent carotid ultrasound examinations at baseline in the 4^th (1994–5) and at follow-up in the 6^th survey (2007–8). Of these, 278 men and 273 women fulfilled the criteria for the MetS, defined according to a modified version of the National Cholesterol Education Program Adult Treatment Panel III (NCEP, ATPIII). Carotid atherosclerosis was assessed as total plaque area (TPA) and mean intima-media thickness (IMT) at follow-up and as change in IMT and TPA from baseline to follow-up. Associations between MetS and its components and carotid atherosclerosis were assessed in linear regression models adjusted for age, total cholesterol and daily smoking, stratified by sex.

Results

IMT and TPA levels at follow-up (p < 0.0001) and progression of TPA (p = 0.02) were higher in the MetS group compared to the non-MetS group. In stepwise multivariable models, MetS was associated with TPA (β = 0.372 mm², p = 0.009) and IMT (β = 0.051 mm, p < 0.0001) in men, and with IMT (β = 0.045 mm, p = 0.001) in women after 13 years of follow-up, but not with progression of IMT or TPA. In analyses stratified by age, MetS predicted progression of IMT (β = 0.043 mm, p = 0.046) and TPA (β = 1.02 mm^2, p = 0.002) in men below 50 years of age. Hypertension was predictive of follow-up TPA and IMT in both genders and of progression of TPA in women. Impaired glucose tolerance was associated with follow up levels of IMT and TPA as well as progression in IMT in men. None of the other components of MetS were associated with progression of atherosclerosis.

Conclusions

Subjects with MetS had higher levels of IMT and TPA at follow up than those without MetS. Mets predicted progression of IMT and TPA in those below 50 years of age, but not in other age groups, indicating that MetS may be involved in the initiation of the atherosclerotic process.

Previous gestational diabetes is independently associated with increased carotid intima-media thickness, similarly to metabolic syndrome - a case control study

Background

Women with previous gestational diabetes mellitus (pGDM) face a higher risk of developing type 2 diabetes and, consequently, a higher cardiovascular risk. This study aimed to compare the carotid intima-media thickness (cIMT) from young women with pGDM to those with metabolic syndrome (MS) and to healthy controls (CG) to verify whether a past history of pGDM could be independently associated with increased cIMT.

Methods

This is a cross-sectional study performed in two academic referral centers. Seventy-nine women with pGDM, 30 women with MS, and 60 CG aged between 18 and 47 years were enrolled. They all underwent physical examination and had blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDLc), and triglycerides determined. The cIMT was measured by ultrasound in several carotid segments. The primary endpoint was cIMT and clinically relevant parameters included as predictors were: age, systolic blood pressure, waist, BMI, total cholesterol, LDLc, triglycerides, fasting glucose, previous history of GDM as a whole group, previous history of GDM without MS, presence of DM, presence of MS, and parity.

Results

cIMT was significantly higher in pGDM when compared to CG in all sites of measurements (P < 0.05) except for the right common carotid. The pGDM women showed similar cIMT measurements to MS in all sites of measurements, except for the left carotid bifurcation, where it was significantly higher than MS (P < 0.001). In a multivariate analysis which included classical cardiovascular risk factors and was adjusted for confounders, pGDM was shown to be independently associated with increased composite cIMT (P < 0.01). The pGDM without risk factors further showed similar cIMT to MS (P > 0.05) and an increased cIMT when compared to controls (P < 0.05).

Conclusions

Previous GDM was independently associated with increased composite cIMT in this young population, similarly to those with MS and regardless the presence of established cardiovascular risk factors.

Reproductive factors and serum uric acid levels in females from the general population: the KORA F4 study

Objective

Hyperuricemia is associated with an increased risk of metabolic and cardiovascular diseases. There are pronounced sex differences in the levels of uric acid. It is largely unknown whether or not reproductive parameters which induce hormonal changes are responsible for this. We examined if there are associations between reproductive parameters and uric acid levels in a female population-based sample.

Methods

In this cross-sectional analysis, data of 1530 women aged 32 to 81 years participating in the KORA F4 study, conducted between 2006 and 2008 in Southern Germany were used. Reproductive parameters were obtained by standardized interviews. Uric acid levels were tested by the uricase method. The whole study sample and stratified in pre- and postmenopausal women was analyzed.

Results

Menopausal status and earlier age at menarche were associated with higher serum uric acid levels (age-adjusted: p-values 0.003, <0.001 respectively; after multivariable adjustment, including BMI: p-values 0.002, 0.036). A history of oral contraceptive use showed an association with uric acid levels only after multivariable adjustment (p-value 0.009). Hot flushes showed an association with uric acid levels only after age-adjustment (p-value 0.038), but lost significance after adding other confounders. Other reproductive factors, including parity, current or ever use of hormone replacement therapy, current use of oral contraceptives, hysterectomy, bilateral oophorectomy, or depressive mood related to menopausal transition were not associated with uric acid levels.

Conclusions

Postmenopausal status, earlier age at menarche and a history of oral contraceptive use were independently associated with higher serum uric acid concentrations in women from the general population. Further studies, especially longitudinal population-based studies investigating the relationship of female reproductive parameters with uric acid levels are necessary to confirm our findings.

Uric acid is an independent risk factor for carotid atherosclerosis in a Japanese elderly population without metabolic syndrome

Background

Carotid intima-media thickness (IMT) is an useful surrogate marker of cardiovascular disease. Associations between uric acid (UA), metabolic syndrome (MetS) and carotid IMT have been reported, but findings regarding the relationship have been inconsistent.

Methods

A total of 1,579 Japanese elderly subjects aged ≥65 years {663 men aged, 78 ± 8 (mean ± standard deviation) years and 916 women aged 79 ± 8 years} were divided into 4 groups according to UA quartiles. We first investigated the association between UA concentrations and confounding factors including MetS; then, we assessed whether there is an independent association of UA with carotid IMT and atherosclerosis in participants subdivided according to gender and MetS status.

Results

Carotid IMT was significantly increased according to the quartiles of UA in both genders without MetS and women with MetS. Multivariate logistic regression analysis showed that odds ratio (OR) {95% confidence interval (CI)} in men for carotid atherosclerosis was significantly increased in the third (OR, 1.75; 95% CI, 1.02-3.02), and fourth quartiles (OR, 2.01; 95% CI, 1.12-3.60) of UA compared with that in the first quartile of UA, and the OR in women was significantly increased in the fourth quartile (OR, 2.10; 95% CI, 1.30-3.39). Similarly, the ORs were significantly associated with increasing quartiles of UA in both genders without MetS, but not necessarily increased in those with MetS.

Conclusions

UA was found to be an independent risk factor for incidence of carotid atherosclerosis in both genders without MetS.

A structural equation model for assessment of links between changes in serum triglycerides, -urate, and -glucose and changes in serum calcium, -magnesium and -phosphate in type 2 diabetes and non-diabetes metabolism

Background

This study investigates the associations between changes in serum Triglycerides (S-TG), -Urate (S-Urate), and -Glucose (S-Glu) and changes in serum Calcium (S-Ca), -Magnesium (S-Mg), and -Phosphate (S-P) in patients with type 2 diabetes compared with non-diabetic patients.

Methods

The analysis is based on data collected from a secondary prevention population of women and men (W/M) at risk for cardiovascular disease (type 2 diabetes, 212/200; non-diabetes 968/703). The whole population (n = 2083) had a mean age of 51.0 (9.7) years and was stratified for sex and according to type 2 diabetes or non-diabetes. The patients were followed for, either half a year or one year and changes in risk factors were calculated from follow-up to baseline, the time when patients were admitted to the health center. The pattern of relationships was evaluated using a structural equation model.

Results

Higher S-TG and S-Glu but lower S-Urate was revealed at baseline in type 2 diabetes women and men as compared to their counterparts, non-diabetes patients. Women with type 2 diabetes had higher S-Ca and lower S-Mg than non-diabetes women. Changes in S-Glu were associated with changes in S-Ca (+), baseline S-Ca (+), and S-Urate (-) in type 2 diabetes men. Changes in S-Urate were associated with changes in S-Mg (+) in type 2 diabetes women and non-diabetes men. In men with non-diabetes, changes in S-Glu were associated with changes in S-Mg (-). In women with non-diabetes, changes in S-Glu were associated with changes in S-P (-) and changes in S-Urate with changes in S-Ca (+).

Conclusion

With respect to metabolic disturbances in non-diabetes and the awareness of risk for type 2 diabetes, changes in S-Glu and changes in S-Ca, S-Mg, and S-P should be considered as risk factors for cardiovascular disease. Increased early detection and corrections of high S-Ca, low S-Mg, and S-P in obese patients may improve their metabolism and reduce the risk of CVD in patients with type 2 diabetes.

Trial registration number

ISRCTN: ISRCTN79355192

Association of circulating omentin-1 level with arterial stiffness and carotid plaque in type 2 diabetes

BACKGROUND

Adipokines contribute directly to the atherosclerotic process, connecting metabolic disorders such as obesity and diabetes to cardiovascular disease. Omentin-1 is a recently discovered novel adipokine, so data about the relationship of this adipokine to vascular health in type 2 diabetes is limited.

METHODS

We enrolled 60 people with type 2 diabetes, with or without carotid plaque, and 30 participants with normal glucose tolerance. We measured serum omentin-1, high-sensitivity C-reactive protein (hsCRP) levels, and the homeostasis model assessment of insulin resistance (HOMA-IR), as well as other cardiovascular risk factors. Vascular health was assessed by brachial ankle pulse wave velocity (baPWV) and carotid intima-media thickness (IMT).

RESULTS

Serum omentin-1 levels were significantly decreased in type 2 diabetes patients compared to normal glucose controls and was further reduced in type 2 diabetes patients with carotid plaque compared to those without carotid plaque. Multiple stepwise regression analysis showed that age, systolic blood pressure, history of use of statins, angiotensin receptor blockers or angiotensin-converting enzyme inhibitors, and serum omentin-1 level were independent factors determining baPWV in people with type 2 diabetes (r2 = 0.637). Furthermore, in multivariate logistic regression analysis, circulating omentin-1 level was an independent decisive factor for the presence of carotid plaque in type 2 diabetes patients, even after adjusting for age, gender, body mass index, systolic blood pressure, fasting blood glucose, low density lipoprotein cholesterol, and history of smoking and medication (odds ratio, 0.621; 95% confidence interval, 0.420-0.919; P = 0.017).

CONCLUSIONS

Circulating omentin-1 level was independently correlated with arterial stiffness and carotid plaque in type 2 diabetes, even after adjusting for other cardiovascular risk factors and detailed medication history.

Hyperuricemia is independently associated with coronary heart disease and renal dysfunction in patients with type 2 diabetes mellitus

AIMS

To investigate the relationship between hyperuricemia (HUA) and the clinical backgrounds in Japanese patients with type 2 diabetes mellitus.

METHODS

After a cross-sectional study evaluating the association of HUA with the clinical characteristics in 1,213 patients with type 2 diabetes mellitus, the estimated glomerular filtration rate (eGFR) and the incidence of diabetic macroangiopathies was investigated in a prospective observational study in 1,073 patients during a 3.5 year period. HUA was defined by serum uric acid levels >327 μmol/L or as patients using allopurinol.

RESULTS

The frequency of HUA was significantly higher in the diabetic patients (32% in men and 15% in women) than in the normal controls (14% in men and 1% in women). In total, HUA was found in 299 (25%) of the patients during the cross-sectional study. Even after adjusting for sex, drinking status, treatment for diabetes mellitus, body mass index, hypertension, use of diuretics, hyperlipidemia, HbA1c and/or the eGFR, the HUA was independently associated with some diabetic complications. The eGFR was significantly reduced in HUA patients compared to those with normouricemia in the 12 months after observation was started. HUA was also an independent risk factor for coronary heart disease even after adjustment in the Cox proportional hazard model.

CONCLUSIONS

HUA is a associated with diabetic micro- and macroangiopathies. HUA is a predictor of coronary heart disease and renal dysfunction in patients with type 2 diabetes mellitus. However, the influence of HUA is considered to be limited.