The Relation between Serum Uric Acid and HbA1c Is Dependent upon Hyperinsulinemia in Patients with Newly Diagnosed Type 2 Diabetes Mellitus

Association between serum uric acid levels and cardiovascular risk factors among adults in India

BACKGROUND AND AIM

The objective of this study was to explore the association between serum uric acid (SUA) levels and cardiovascular risk factors in the Indian population.

METHODS AND RESULTS

This was a cross-sectional, population-based study. The study enrolled adults aged 20 years and above residing in rural, sub-urban, and urban. All participants completed a detailed questionnaire, underwent anthropometric measurements, and had blood samples collected. Participants were divided into three tertiles based on their SUA concentrations. A total of 2976 participants were included in this study, with 865 from rural, 1030 from sub-urban, and 1081 from urban populations. The mean values of cardiovascular risk factors were significantly higher in tertile 3 (p < 0.001) as compared to the other tertiles. However, we observed a negative trend between the increase of SUA and SUA/Scr ratio and HbA1c levels (Pearson correlation r = -0.068; p < 0.001 and r = -0.140; p < 0.001, respectively). The healthy and prediabetic groups did not show any significant change in HbA1c with increasing SUA levels, while an inverse trend was observed in diabetics. In the diabetic population, both men and women showed an inverse trend between increasing SUA levels and HbA1c in both known and newly diagnosed diabetes (p < 0.001).

CONCLUSIONS

The study found a positive association between SUA levels and cardiovascular risk factors. However, HbA1c was inversely correlated with increasing SUA tertiles in both known and newly diagnosed diabetes, as compared to the general population. Additionally, both men and women with diabetes consistently showed an inverse relationship between increasing SUA/SCr ratio and HbA1c levels.

Optimization of uric acid detection with Au nanorod-decorated graphene oxide (GO/AuNR) using response surface methodology

A modified glassy carbon electrode (GCE) was developed based on a synthesized graphene oxide (GO) gold nanorod (AuNR) decorated composite (GO/AuNR) for sensitive electrochemical sensing of uric acid (UA). The electrochemical performance of GO/AuNR/GCE for UA detection was investigated employing the differential pulse voltammetry (DPV) technique. Central composite design (CCD) was applied to obtain the optimum composition of the GO and AuNR composite, which provide the highest possible UA oxidation peak current. The optimum composition was obtained at a GO concentration of 5 mg mL-1 and AuNR volume of 10 mL. Under the optimum conditions, GO/AuNR/GCE showed acceptable analytical performance for UA detection with good linearity (concentration range of 10-90 μM) and both a low detection limit (0.4 μM) and quantitation limit (1.0 μM). Furthermore, the proposed sensor exhibits superior stability, reproducibility, and selectivity using ascorbic acid (AA), dopamine (DA), urea, glucose, and magnesium as interferents. Finally, practical use of GO/AuNR/GCE was demonstrated by successfully determining the content of UA in human urine samples with the standard addition approach.

Dose-Response Relationship of Uric Acid With Fasting Glucose, Insulin, and Insulin Resistance in a United States Cohort of 5,148 Non-diabetic People

Background

There is a limited number of studies on the dose-response relationship between serum uric acid and impaired glucose metabolism in people without diabetes, and no large-scale research exploring the relationship in women without diabetes is based on menopausal status. Consequently, the present study aimed to investigate the above relationship in United States adults without diabetes.

Materials and Methods

Data from 2,498 men and 2,650 women aged ≥20 years were obtained from the National Health and Nutrition Examination Survey 2011-2016 conducted in the United States. Binary logistic regression analysis was applied to evaluate the association between uric acid and impaired glucose metabolism. Restricted cubic spline analysis, sensitivity analysis, and stratified analysis by menopausal status were performed to explore the above relationships.

Results

A positive correlation was found between uric acid and the risk of insulin resistance in all participants (P < 0.05). In binary logistic regression analysis, after adjusting for confounding factors, compared with the lowest quartile of uric acid, the odds ratio (95% confidence intervals) of insulin resistance in the highest quartile was 1.9 (1.1-3.1) and 2.2 (1.2-4.3) in men and women, respectively. A significant positive relationship was also observed between uric acid and impaired fasting glucose and hyperinsulinemia in women, while in men, uric acid was positively associated with the risk of hyperinsulinemia but not impaired fasting glucose. Restricted cubic spline showed that the odds ratios of insulin resistance and hyperinsulinemia increased with elevating uric acid levels in both men and women. When stratified by menopause, the association remained significant in pre-menopausal women aged ≥20, but insignificant in post-menopausal women.

Conclusion

Uric acid was positively associated with the risk of impaired glucose metabolism in a cohort of United States adults, and uric acid increased the risk of insulin resistance in pre-menopausal, but not in post-menopausal women.

Serum uric acid is positively associated with the prevalence of nonalcoholic fatty liver in non-obese type 2 diabetes patients in a Chinese population

AIMS

To investigate whether SUA is independently associated with NAFLD in non-obese type 2 diabetic patients in a Chinese population.

METHODS

A cross-sectional study was carried out among 400 non-obese type 2 diabetic inpatients. Patients were stratified according to SUA levels and presence/absence of NAFLD. The clinical and laboratory features were collected retrospectively. Multivariate logistic regression analysis was conducted to estimate odds ratios of SUA for NAFLD.

RESULTS

The levels of SUA were significantly higher in patients with NAFLD than those without NAFLD. SUA was positively associated with the risk factors of NAFLD such as BMI, serum insulin and lipids. The odds of NAFLD were increasingly higher from the second to the fourth quartile of SUA as compared to the lowest quartile. After adjustment for age, gender, BMI and other metabolic components, the odds of NAFLD remained significantly increased for quartile 4.

CONCLUSIONS

SUA levels are strongly and independently associated with the prevalence of NAFLD. SUA may be used as a useful predictor to stratify the higher risks for NAFLD of non-obese type 2 diabetes patients.

Role and Risk Factors of Glycosylated Hemoglobin Levels in Early Disease Screening

OBJECTIVE

To clarify the correlation among glycosylated hemoglobin (HbA1c), gender, age, fatty liver, and biochemical indicators through the analysis of big database, and to further investigate the risk factors affecting HbA1c, so as to lay a foundation for the study of HbA1c-related diseases and disease management.

METHODS

People who have been examined in Health Promotion Center from July 2018 to June 2019 were selected as the research objects. All data were analyzed using the Windows R software (version 3.5.1). Detailed medical history inquiry, laboratory examination, and B-ultrasound examination were carried out for the selected sample population. We determined the sample population according to the inclusion and exclusion criteria and, then, further grouped and analyzed the data. T-test or Mann-Whitney U test was used for continuous variable comparison, and chi-square test was used to compare categorical variables. Logistic regression analysis was used to analyze the risk factors of HbA1c.

RESULTS

A total of 23,933 subjects were included in this study. The HbA1c level of men was significantly higher than that of women, the HbA1c level of the group with diabetes was higher than that of the group with no diabetes, and the HbA1c level of the group with fatty liver was higher than that of the group with no fatty liver. In the group with no diabetes, the HbA1c level increased with weight gain. Age, gender (male), fatty liver, waist circumference, systolic blood pressure (SBP), triglyceride (TG), blood urea nitrogen (BUN), free thyroxine (FT4), and red blood cell (RBC) were the risk factors for elevated HbA1c level, while high-density lipoprotein cholesterol (HDL-C), uric acid (UA), creatinine (Cr), free triiodothyronine (FT3), and hemoglobin were protective factors.

CONCLUSION

Blood glucose, age, weight, gender, fatty liver, blood lipids, and UA are related to the increase of HbA1c level. HbA1c is related to many metabolic indexes and may be used as a marker for early detection of chronic diseases.

A relation of serum homocysteine and uric acid in Bosnian diabetic patients with acute myocardial infarction

Background: Coronary artery disease as a consequence of atherosclerosis is the most common cause of morbidity and mortality in type 2 Diabetes Mellitus (DM) patients. Homocysteine (HCY), as one of the risk factors, and uric acid (UA) as the most common antioxidant in serum have their roles in the processes of inflammation and atherogenesis, which underlie the pathogenesis of acute myocardial infarction (AMI). The effect of HCY in cardiovascular disease is thought to be manifested primarily through oxidative damage, implying a potential correlation between the HCY level and antioxidant status. Since the data related to the diagnostic significance of both HCY and UA in diabetic patients with AMI are conflicting, and so far not reported in Bosnian patients, this research aimed to examine the association of HCY and UA levels with glomerular filtration rate (eGFR) and explore the pathophysiological significance of these data in Bosnian diabetic patients with AMI.

Methods: This prospective research included 52 DM type 2 patients diagnosed with AMI. Blood samples were taken on admission and used for biochemical analysis. Results of the biochemical analyses were statistically analysed.

Results: Elevated HCY and UA levels were observed in diabetic patients. Females have higher HCY compared to males. A positive correlation was revealed between HCY and UA and was confirmed with different HCY levels in subgroups with different UA level. A negative correlation was observed between UA and HbA1c, as well as between both HCY and UA with eGFR.

Conclusions: These results contribute to the clarification of the biochemical mechanisms characteristic in AMI patients with DM. According to these results, we believe that joint measurement of HCY and UA could enable a better assessment of the prognosis for this group of patients. This kind of assessment, as well as regression analysis, can identify high-risk patients at an earlier stage when appropriate interventions can influence a better outcome in such patients.

Evaluation of electrochemical quartz crystal microbalance based sensor modified by uric acid-imprinted polypyrrole

Uric acid-imprinted polypyrrole-based (MIP_(UA)-Ppy) electrochemical quartz crystal microbalance sensor (EQCM) was developed. Experiments and theoretical calculations were focused on molecular interactions between uric acid molecule and: i) polypyrrole imprinted by uric acid (MIP_(UA)-Ppy) ii) polypyrrole film without any molecular imprints (NIP-Ppy). Resonant frequency differences during electrochemical deposition of MIP_(UA)-Ppy and NIP-Ppy films were observed and were attributed to the phenomenon of molecule capture within formed Ppy matrix. EQCM-resonators modified by MIP-Ppy showed the following advantages: selectivity, qualitative response, cost-effectiveness, and simple procedure. The selectivity of MIP_(UA)-Ppy was tested by the replacement of uric acid in the PBS solution with several different concentrations of caffeine and glucose. Langmuir isotherm based molecular adsorption model was applied to evaluate the interaction of MIP_(UA)-Ppy with uric acid. From experimental results calculated the standard Gibbs free energy of association (ΔG_a) of uric acid with MIP_(UA)-Ppy is -16.4 ± 2.05 kJ/mol and with NIP-Ppy is -13.3 ± 8.56 kJ/mol ΔG values illustrate that the formation of uric acid complex with MIP_(UA)-Ppy is thermodynamically more favourable than that for complexation with NIP-Ppy.

Hyperuricaemia is associated with dyslipidemia but not HbA1c among type 2 diabetes mellitus patients in Botswana

Medical records and residual samples from 334 type 2 diabetes mellitus patients attending a clinic in Gaborone, Botswana, during the period September–December 2016 were analysed for the effects of hyperuricaemia on biochemical markers of adverse outcomes. The patients were stratified as having hyperuricaemia (> 400 µmol/L) or normal serum uric acid (≤ 400 µmol/L). We compared glycated haemoglobin, triglycerides, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, total cholesterol and serum creatinine between the two serum uric acid categories. Hyperuricaemia was detected in 28% of patients (95% confidence interval 23.1–32.9) and was associated with increased serum triglycerides, triglyceride to high-density lipoprotein-cholesterol ratio and creatinine concentration, but not with glycated haemoglobin.

Clinical, Electrocardiographic, and Echocardiographic Features in Hospitalized Nonagenarians (90+): Comparison between the Genders

OBJECTIVES

We investigated the clinical, electrocardiographic, and echocardiographic determinants of the cardiac status in nonagenarian patients.

METHODS

We consecutively examined 654 Caucasian patients (232 males and 422 females) aged ≥90 years. All patients underwent clinical examination, ECG, and transthoracic echocardiography.

RESULTS

Their average age was 92.5 ± 2.5 years. Patients were predominately female of older age (p < 0.0001 and p = 0.02, respectively). A history of cardiovascular disease was present in 78.4% of the participants. One third of the patients was hospitalized for cardiovascular causes, with females being twice as many (p < 0.0001). Females showed higher levels of serum cholesterol, triglycerides, and glycemia (p < 0.0001, p< 0.0001, and p = 0.04 respectively). Sinus rhythm was detected in 65%, and atrial fibrillation in 31% of the overall population. Heart rate, PR and corrected QT (QTc) intervals, right bundle branch block (RBBB) and RBBB associated with left anterior fascicular block (LAFB) were higher in males (p < 0.0001, p = 0.036, p = 0.009, p = 0.001, and p = 0.004, respectively). Aortic root dimension, left ventricular (LV) mass index, and indexed LV systolic-diastolic volumes were higher in males (p < 0.001, p < 0.0001, p < 0.001, and p < 0.0001, respectively). Women showed fewer LV segmental kinetic disorders (p = 0009) and higher LV ejection fraction (LVEF; p< 0.0001). Hyperuricemia was positively associated with a history of cardiovascular disease (r = 0.15), glycemia (r = 19), creatininemia (r = 0.50), uremia (r = 0.51), triglycerides (r = 0.19), PR interval (r = 0.14), and left bundle branch block (r = 0.11), and inversely associated with sinus rhythm (r = -0.14) and LVEF (r = -0.17). Diabetes was positively correlated with PR and QTc intervals (r = 0.14 and r = 0.10, respectively), and RBBB with LFAB (r = 0.10), and inversely correlated with LVEF (r = -0.10).

CONCLUSIONS

We found a remarkable presence of cardiovascular risk factors, ECG, and structural alterations in hospitalized nonagenarians, which presents more commonly in males.

The relationship between serum uric acid within the normal range and β-cell function in Chinese patients with type 2 diabetes: differences by body mass index and gender

Background

Elevated serum uric acid (SUA) has a positive correlation with insulin secretion and insulin resistance indexes. However, whether weight- and gender-specific differences regarding the relationship between SUA within the normal range and β-cell function and insulin resistance exist is unknown in type 2 diabetes mellitus (T2DM) patients.

Methods

A total of 380 patients with type 2 diabetes were divided into two groups as overweight/obesity (n = 268) and normal weight (n = 112). Each group were again divided into low (LSUA) and high normal SUA (HSUA). The HbA1c, C-peptide, SUA, creatinine, and lipids profiles were measured. HOMA2IR and HOMA%2B were estimated using fasting glucose and C-peptide by homeostasis model assessment (HOMA). Pearson’s correlations and multiple linear regression analyses were conducted to assess the associations between SUA levels and islet function indexes.

Results

In overweight/obesity subgroup, the levels of body mass index, fasting C-peptide (FCP), P2hCP, fasting CPI (FCPI), postprandial CPI (PPCPI), ΔC-peptide, HOMA2%B, and HOMA2IR were higher in HSUA group than in LSUA group. In contrast, the HbA1c, FBS, and P2hBS were lower in HSUA than in LSUA. In normal weight subgroup, there were no differences between the HSUA than LSUA group in terms of clinical characteristics. Pearson’s correlations indicated that there were no significant correlations between SUA and insulin secretory capacity in normal weight group, but in overweight/obesity group, SUA had positive significant correlations with P2hCP, FCPI, PPCPI, ΔC-peptide, and HOMA2%B. In the female group, there were no significant correlations between SUA and insulin secretory capacity. However, in the male group, SUA had positive significant correlations with insulin secretory capacity include P2hCP, FCPI, PPCPI, ΔC-peptide, and HOMA2%B. Multiple linear regression showed that SUA was significantly associated with HOMA2%B, but not with HOMA2IR in overweight/obesity and male group.

Conclusions

Our study shows that SUA levels within normal range were associated with β-cell function in T2DM patients with overweight/obesity or male. This finding supports that the association between SUA within normal range and insulin secretion ability differs by weight and sex.

The Impact Of Hyperuricemia On Cardiometabolic Risk Factors In Patients With Diabetes Mellitus: A Cross-Sectional Study

PURPOSE

Hyperuricemia (HUA) is linked to a variety of non-communicable diseases such as atherosclerotic cardiovascular disease (ASCVD), chronic kidney disease (CKD) and hypertension, with evidence showing its role in the development of diabetes mellitus (DM). Our study's main aim was to explore the associations of HUA with other traditional risk factors in Romanian patients with DM and to assess the impact of the increase of serum UA on DM complications and HbA1c.

PATIENTS AND METHODS

In this cross-sectional, non-interventional study, we enrolled, according to a population-based, consecutive-case principle, 133 patients previously diagnosed with DM. HbA1c, uric acid, lipid profile, urinary albumin/creatinine ratio, glomerular filtration rate, TSH and FT₄ measurements were performed, while the diagnosis of retinopathy and of diabetic neuropathy was established using standardized methods.

RESULTS

An increased uric acid level was associated with a significant increase in the risk for development of stroke (OR=1.526; p=0.004). A weak, positive and statistically significant correlation can also be observed between the BMI and the presence of hyperuricemia (r=0.131; p=0.034), and between the triglyceride levels and hyperuricemia (r= 0.173; p=0.004). Glomerular filtration rate was correlated to hyperuricemia in a strong and negative manner, having an important statistical significance (r=-0.818; p=0.003). In our study, UA levels and HbA1c were negatively correlated, without reaching statistical significance.

CONCLUSION

Serum UA is strongly correlated with the BMI, triglyceride level and GFR in Romanian patients with DM and HUA is significantly associated with a higher risk of stroke in these individuals.

Fructose Consumption, Lipogenesis, and Non-Alcoholic Fatty Liver Disease

Increased fructose consumption has been suggested to contribute to non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and insulin resistance, but a causal role of fructose in these metabolic diseases remains debated. Mechanistically, hepatic fructose metabolism yields precursors that can be used for gluconeogenesis and de novo lipogenesis (DNL). Fructose-derived precursors also act as nutritional regulators of the transcription factors, including ChREBP and SREBP1c, that regulate the expression of hepatic gluconeogenesis and DNL genes. In support of these mechanisms, fructose intake increases hepatic gluconeogenesis and DNL and raises plasma glucose and triglyceride levels in humans. However, epidemiological and fructose-intervention studies have had inconclusive results with respect to liver fat, and there is currently no good human evidence that fructose, when consumed in isocaloric amounts, causes more liver fat accumulation than other energy-dense nutrients. In this review, we aim to provide an overview of the seemingly contradicting literature on fructose and NAFLD. We outline fructose physiology, the mechanisms that link fructose to NAFLD, and the available evidence from human studies. From this framework, we conclude that the cellular mechanisms underlying hepatic fructose metabolism will likely reveal novel targets for the treatment of NAFLD, dyslipidemia, and hepatic insulin resistance. Finally, fructose-containing sugars are a major source of excess calories, suggesting that a reduction of their intake has potential for the prevention of NAFLD and other obesity-related diseases.

Fructose use in clinical nutrition: metabolic effects and potential consequences

PURPOSE OF REVIEW

The current article presents recent findings on the metabolic effects of fructose.

RECENT FINDINGS

Fructose has always been considered as a simple 'caloric' hexose only metabolized by splanchnic tissues. Nevertheless, there is growing evidence that fructose acts as a second messenger and induces effects throughout the human body.

SUMMARY

Recent discoveries made possible with the evolution of technology have highlighted that fructose induces pleiotropic effects on different tissues. The fact that all these tissues express the specific fructose carrier GLUT5 let us reconsider that fructose is not only a caloric hexose, but could also be a potential actor of some behaviors and metabolic pathways. The physiological relevance of fructose as a metabolic driver is pertinent regarding recent scientific literature.