The Association of Serum Uric Acid with Beta-Cell Function and Insulin Resistance in Nondiabetic Individuals: A Cross-Sectional Study

Association between serum uric acid and the risk of breast cancer: A meta-analysis of observational studies

BACKGROUND

The relationship between serum uric acid and breast cancer remains uncertain. This meta-analysis aimed to elucidate the dose-response association between elevated serum uric acid levels and breast cancer risk.

METHODS

We systematically searched PubMed, Embase, and Web of Science for observational studies evaluating serum uric acid and breast cancer risk in adult women. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model.

RESULTS

Ten studies were included. High serum uric acid was associated with an increased breast cancer risk (RR: 1.34; 95% CI: 1.03-1.73; P = 0.03; I2 = 78%). Meta-regression analysis revealed that the cutoff for high serum uric acid positively correlated with breast cancer risk (coefficient = 0.24; P < 0.001), explaining heterogeneity (residual I2 = 0%). Subgroup analysis demonstrated a high serum uric acid was significantly related to an increased breast cancer risk in studies with a cutoff value ≥ 5.4 mg/dL (RR: 1.95; P < 0.001), but not in those with a cutoff value < 5.4 mg/dL (RR: 0.97; P = 0.44). The dose-response meta-analysis revealed a U-shaped association between serum uric acid levels and the risk of breast cancer (P for nonlinearity = 0.013). The risk of breast cancer fell until around 4.5 mg/dL of serum uric acid, and increased afterward.

CONCLUSION

Serum uric acid may be nonlinearly associated with the risk of breast cancer (U-shaped). The risk of breast cancer increases with serum uric acid above 4.5 mg/dL, and a higher association between serum uric acid and the increased risk of breast cancer could be observed in studies with cutoff of serum uric acid  > 5.4 mg/dL.

Insufficient compensatory pancreatic β-cells function might be closely associated with hyperuricemia in U.S. adults: evidence from the National Health and Nutrition Examination Survey

BACKGROUND

The prevalence of hyperuricemia (HUA) is gradually increasing worldwide. HUA is closely related to diabetes, but the relationship between HUA and pancreatic β-cells function in the population is unclear. The purpose of this article is to investigate the association between pancreatic β-cells and HUA.

METHODS

This cross-sectional study examined the association between pancreatic β-cells and HUA in 1999-2004 using data from the National Health and Nutrition Examination Survey (NHANES). Subjects were divided into two groups: HUA and non-HUA. Pancreatic β-cells function levels were assessed using homeostasis model assessment version 2-%S (HOMA2-%S), homeostasis model assessment version 2-%B (HOMA2-%B) and disposition index (DI). Multivariate logistic regression models and restricted cubic spline models were fitted to assess the association of pancreatic β-cells function with HUA.

RESULTS

The final analysis included 5496 subjects with a mean age of 46.3 years (standard error (SE), 0.4). The weighted means of HOMA2-%B, HOMA2-%S and DI were 118.1 (SE, 1.0), 69.9(SE, 1.1) and 73.9 (SE, 0.7), respectively. After adjustment for major confounders, participants in the highest quartile of HOMA2-%B had a higher risk of HUA (OR = 2.55, 95% CI: 1.89-3.43) compared to participants in the lowest quartile. In contrast, participants in the lowest quartile of HOMA2-%S were significantly more likely to have HUA than that in the highest quartile (OR = 3.87, 95% CI: 2.74-5.45), and similar results were observed in DI (OR = 1.98, 95% CI: 1.32-2.97). Multivariate adjusted restricted cubic spline analysis found evidence of non-linear associations between HOMA2-%B, HOAM2-%S, DI and the prevalence of HUA.

CONCLUSION

Our finding illustrated the indicators of inadequate β-cells compensation might be a new predictor for the presence of HUA in U.S. adults, highlighting a critical role of pancreatic β-cells function on HUA.

Interrelationship of hemoglobin A1c level lipid profile, uric acid, C-reactive protein levels and age in a large hospital database

INTRODUCTION

Hemoglobin A1c (HbA1c) is used to monitor glucose homeostasis and to identify risk for diabetes. As diabetic patients are frequently present with dyslipidaemia, low-grade inflammation and hyperuricemia, we tested whether HbA1c levels can be estimated having the information about lipid profile, uric acid (UA) and C-reactive protein (CRP) levels. We developed formulas to describe the association of these parameters with HbA1c levels.

METHODS

Data of 9599 male and 10,817 female patients, measured between 2008 and 2018, were analysed. Patients represented a general hospital patient population with overrepresentation of those with elevated HbA1c over 5.6%. The impact of gender, age, CRP, lipid profile and UA levels on HbA1c % on HbA1c levels was tested with multiple linear regression model. The magnitude of effects of individual factors was used to develop formulas to describe the association between HbA1c and other cardiometabolic parameters. With these formulas we estimated median HbA1c values in each age in both gender and compared them to measured HbA1c levels.

RESULTS

The developed formulas are as follow: HbA1c (estimated) in women = 0.752 + 0.237*log10(HDL/cholesterol) + 0.156*log10 (cholesterol) + 0.077*log10 (triglyceride) + 0.025*log10(CRP) +0.001*log10 (age) -0.026*log10(HDL/LDL) -0.063*log10 (uric acid)-0.075*log10 (LDL)-0.199*log10(HDL); HbA1c (estimated) in men = 1.146 + 0.08*log10 (triglyceride) + 0.046*log10(CRP) + 0.01*log10 (cholesterol) + 0.001*log10 (age) -0.014*log10(HDL)-0.018*log10(HDL/LDL)-0.025*log10(HDL/cholesterol) -0.068*log10 (LDL)-0.159*log10 (uric acid) Between 20 and 70 years of age, estimated HbA1c matched perfectly to measured HbA1c in.

CONCLUSION

At population level, HbA1c levels can be estimated almost exactly based on lipid profile, CRP and uric acid levels in female patients between 20 and 70 years.

[Value of C-peptide-based insulin resistance index for evaluating correlation between insulin resistance and serum uric acid level in individuals undergoing health examination]

OBJECTIVE

To investigate the value of C-peptide-based insulin resistance index in evaluating the correlation between insulin resistance and serum uric acid (Ua) level in subjects undergoing health examination.

METHODS

The data of 46 017 subjects undergoing health examination were retrospectively collected from the Second Medical Center of PLA General Hospital from January, 2017 to December, 2021. The subjects were divided into Ua≤420 μmol/L group and Ua>420 μmol/L group for comparison of HOMA insulin resistance index (HOMA2-IR) and HOMA insulin resistance-C peptide (HOMA2 IR-CP). The correlations of HOMA2-IR and HOMA2 IR-CP with Ua level were analyzed using Pearson correlation analysis and linear regression analysis. Hierarchical interaction analysis was conducted to assess the differences in the association between insulin resistance index and Ua level in different subgroups. The ROC curve was used to evaluate the predictive ability of insulin resistance index for an increased Ua level.

RESULTS

The levels of HOMA2-IR and HOMA2 IR-CP were significantly lower in Ua≤420 μmol/L group than in Ua>420 μmol/L group. Univariate Pearson correlation analysis showed a weak correlation of HOMA2-IR with Ua (r=0.262, P<0.001) and moderate correlation of HOMA2 IR-CP with Ua (r=0.409, P<0.001). Multivariate linear regression analysis, after adjustment for confounding factors, demonstrated that HOMA2-IR (R2=0.445, P<0.001) and HOMA2 IR-CP (R2=0.461, P<0.001) were both factors affecting Ua level. Hierarchical interaction analysis showed that the association of insulin resistance index with Ua level varied significantly with gender, age, and glucose metabolism (P<0.001). ROC curve showed that the areas under the curve predicted an increased Ua level by HOMA2-IR and HOMA2 IR-CP were 0.662 and 0.722, respectively.

CONCLUSIONS

HOMA2 IR-CP is a more accurate indicator for assessing the correlation between insulin resistance and Ua level.

Relationship between baseline and changed serum uric acid and the incidence of type 2 diabetes mellitus: a national cohort study

Objective

To explore the correlation between baseline serum uric acid (SUA) and SUA changes with the incidence of type 2 diabetes mellitus (T2DM) among middle-aged and older individuals.

Method

Binary logistic regression was used to calculate the odds ratio (ORs) and 95% confidence intervals (CIs) of the effects of baseline and changes in SUA on the incidence of T2DM. Stratified analysis was conducted based on sex, and the SUA levels were classified into four quartiles to assess the effect of baseline and relative changes in SUA on the incidence of T2DM. Furthermore, interaction analysis was performed between body mass index (BMI) and SUA, age and SUA, and sex and SUA.

Results

In the cohort study, the highest quartiles of SUA were significantly correlated with an increased incidence of T2DM among females in model 1 [OR = 2.231 (1.631, 3.050)], model 2 [OR = 2.090 (1.523, 2.867)], model 3 [OR = 2.075 (1.511, 2.849)], and model 4 [OR = 1.707 (1.234, 2.362)]. The highest quartiles of SUA had a statistically significant effect on the incidence of T2DM among all participants in model 1 [OR = 1.601 (1.277, 2.008)], model 2 [OR = 1.519 (1.204, 1.915)], model 3 [OR = 1.597 (1.257, 2.027)], and model 4 [OR = 1.380 (1.083, 1.760)]. Regarding the relative change of SUA, the highest quantiles of SUA were significantly correlated with an increased incidence of T2DM among females in model 1 [OR = 1.409 (1.050, 1.890)], model 2 [OR = 1.433 (1.067, 1.926)], and model 3 [OR = 1.420 (1.056, 1.910)], and there was a statistically significant correlation with incident T2DM among all participants in model 4 [OR = 1.346 (1.079, 1.680)] after adjusting for all covariates. However, there was no significant correlation between baseline, relative, and absolute changes in SUA and the incidence of T2DM among males. The interaction analysis demonstrated that sex, BMI, and the relative changes in SUA had a combined effect on the incidence of T2DM, while age and the changes in SUA had a joint effect on the incidence of T2DM only in females.

Conclusion

There was a positive association between SUA and the incidence of T2DM for all participants. However, significant sex differences in incidence were observed only in women, not men.

Mechanistic insights of soluble uric acid-induced insulin resistance: Insulin signaling and beyond

Hyperuricemia is a metabolic disease caused by purine nucleotide metabolism disorder. The prevalence of hyperuricemia is increasing worldwide, with a growing trend in the younger populations. Although numerous studies have indicated that hyperuricemia may be an independent risk factor for insulin resistance, the causal relationship between the two is controversial. There are few reviews, however, focusing on the relationship between uric acid (UA) and insulin resistance from experimental studies. In this review, we summarized the experimental models related to soluble UA-induced insulin resistance in pancreas and peripheral tissues, including skeletal muscles, adipose tissue, liver, heart/cardiomyocytes, vascular endothelial cells and macrophages. In addition, we summarized the research advances about the key mechanism of UA-induced insulin resistance. Moreover, we attempt to identify novel targets for the treatment of hyperuricemia-related insulin resistance. Lastly, we hope that the present review will encourage further researches to solve the chicken-and-egg dilemma between UA and insulin resistance, and provide strategies for the pathogenesis and treatment of hyperuricemia related metabolic diseases.

Efficacy and safety of Obex® in overweight and obese subjects: a randomised, double-blind, placebo-controlled clinical trial

BACKGROUND

Obex® may be helpful in reducing body weight and fat. The current study was carried out to evaluate the efficacy and safety of Obex® in the treatment of overweight and obese subjects.

METHODS

A double-blind, randomised, controlled phase III clinical trial was conducted involving 160 overweight and obese subjects (BMI ≥ 25.0 and < 40 kg/m²) aged 20 to 60 years, who received Obex® (n = 80) and placebo (n = 80) plus non-pharmacological treatment (physical activity and nutritional counseling). One sachet of Obex® or placebo were administered before the two main meals each day for 6 months. In addition to anthropometric measurements and blood pressure, fasting plasma and 2 h glucose levels during the oral glucose tolerance test, lipid profile, insulin, liver enzymes, creatinine, and uric acid (UA) were determined, insulin resistance (HOMA-IR) beta-cell function (HOMA-β) were assessed and insulin sensitivity (IS) was calculated with three indirect indexes.

RESULTS

After 3 months of Obex®, 48.3% of the participants (28/58) achieved complete success in reducing both weight and waist circumference by greater than or equal to 5% from baseline, as opposed to 26.0% (13/50) of individuals receiving placebo (p = 0.022). Compared to baseline, at 6 months no differences were found between the groups concerning anthropometric and biochemical measurements, except for high-density lipoprotein cholesterol (HDL-c) levels, which were higher in subjects receiving Obex® compared to those receiving placebo (p = 0.030). After 6 months of treatment, both groups showed reduced cholesterol and triglyceride levels (p < 0.012) compared to baseline value. However, only those intake Obex® showed reduced insulin concentrations and HOMA-IR, improved IS (p < 0.05), and decreased creatinine and UA levels (p < 0.005).

CONCLUSIONS

The consumption of Obex® together with lifestyle changes increased HDL-c, contributed to a rapid reduction of weight and waist circumference, as well as improved insulin homeostasis, which did not occur in the placebo group, and appears to be safe as an adjunct at conventional obesity treatment.

TRIAL REGISTRATION

Clinical trial protocol was registered in the Cuban public registry of clinical trials under code RPCEC00000267 on 17/04/2018 and also registered in the international registry of clinical trials, ClinicalTrials.gov, under code: NCT03541005 on 30/05/2018.

Hyperuricemia as an effect modifier of the association between metabolic phenotypes and nonalcoholic fatty liver disease in Chinese population

BACKGROUND

Different metabolic phenotypes may be related to nonalcoholic fatty liver disease (NAFLD), but such association whether modified by serum uric acid levels is unknown. We examined the association between different metabolic phenotypes and NAFLD and further explore whether hyperuricemia could modify this association.

METHODS

A total of 2959 participants (mean age: 55.02 years) with medical checkups were recruited from Tianjin Medical University General Hospital. Participants were categorized into four groups according to their BMI levels and metabolically healthy status: metabolically healthy normal weight (MHNW), metabolically healthy overweight or obese (MHO), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy overweight or obese (MUO). Blood samples (including serum uric acid) were collected from participants after an overnight fast. NAFLD was diagnosed based on abdominal ultrasonography scanning. Data were analyzed using logistic regression models and the interaction effect model.

RESULTS

The prevalence of NAFLD in MHNW, MHO, MUNW, and MUO groups was 9.9% (7.9-12.0%), 42.8% (39.5-46.1%), 36.5% (31.2-41.9%), and 69.7% (66.8-72.6%), respectively. In multi-adjusted logistic models, the ORs (95% CIs) of NAFLD were 5.32 (4.01-7.04) for participants with MHO, 4.51 (3.17-6.40) for those with MUNW, and 13.68 (10.23-18.30) for those with MUO compared to those with MHNW. In the stratified analysis by uric acid levels, the prevalence of NAFLD was significantly higher in participants with MHO, MUNW, and MUO in the hyperuricemia group than those in the normal uric acid group, and the interaction effect of metabolic phenotypes and uric acid on NAFLD was statistical significant (P < 0.05).

CONCLUSIONS

MHO, MUNW, and MUO were associated with higher prevalence of NAFLD. Serum uric acid levels may modify the association between metabolically phenotypes and NAFLD.

Alpha-mangostin counteracts hyperuricemia and renal dysfunction by inhibiting URAT1 renal transporter in insulin resistance rat model

Background

Alpha-mangostin (AM) has been shown to have hypoglycemic activity. This study aimed to analyze the effects of AM at a dose of 100 mg/kg and 200 mg/kg to alleviate hyperuricemia and renal dysfunction on high-fat/high-glucose diet and low dose streptozotocin (HF/HG/STZ) injection-induced IR rat model. IR was induced in male Wistar rats by giving a HF/HG diet for 11 weeks and single injection of STZ (35 mg/kg, i.p.), then divided randomly into IR rats, IR rats treated with AM 100 and 200 mg/kgBW given by gavage for 8 weeks. At the end of the 11th week, all rats were killed, and the kidneys were taken to be analyzed for urate transporters 1 (URAT1) and glucose transporters 9 (GLUT9). We also assessed serum uric acid, proteinuria, BUN, creatinine clearance, HOMA-IR, and fasting blood glucose (FBG).

Results

We have found the significant increase in HOMA-IR and FBG levels of the IR rats, in comparison with its control groups, which were decreased significantly after AM administration at both doses. URAT1 and GLUT9 mRNA and protein expressions in kidney in the IR + AM at both doses groups also decreased compared those in the IR without treatment group, though the decrease in GLUT9 did not appear to be statistically significant. Consequently, hyperuricemia and renal dysfunction were attenuated by AM treatment at both doses.

Conclusion

After considering all findings, AM might be a potential candidate to ameliorate IR-induced hyperuricemia and renal dysfunction at least in part by modulating the renal URAT1.

Hyperuricemia, a Non-Independent Component of Metabolic Syndrome, Only Predicts Renal Outcome in Chronic Kidney Disease Patients without Metabolic Syndrome or Diabetes

Uric acid (UA) is elevated in metabolic syndrome (MS) and diabetes (DM). UA is associated with central obesity and blood glucose and is proposed as a criterion of MS. Previous reports showed that UA could predict renal outcome in CKD. However, recent clinical trials did not demonstrate the benefits of urate-lowering agents (ULA) for renal outcome. Whether the prognostic value of UA for renal outcome is independent of MS or secondary to MS in CKD patients is unknown. Our study included 2500 CKD stage 1−4 Asian patients divided by UA tertiles and MS/DM. In linear regression, UA was associated with obesity, C-reactive protein, and renal function. In Cox regression, high UA was associated with worse renal outcome in non-MS/DM, but not in MS/DM: hazard ratio (95% confidence interval) of UA tertile 3 was 3.86 (1.87−7.97) in non-MS/DM and 1.00 (0.77−1.30) in MS/DM (p for interaction < 0.05). MS was associated with worse renal outcome, but redefined MS (including hyperuricemia as the 6th criteria) was not. In conclusion, hyperuricemia is associated with worse renal outcome in non-MS/DM and is not an independent component of MS in CKD stage 1−4 patients. Hyperuricemia secondary to MS could not predict renal outcome.

Is Renoprotection Real for Patients with Hyperuricemia?

Number of patients with progressive chronic kidney disease (CKD) is increasing all over the world. One of the risk factors for CKD development and progression is increased serum uric acid (sUA) level. Possibly, control of hyperurcemia with urate lowering therapy drugs can slow the decline in kidney function. The objective: to determine efficacy and safety of allopurinol and febuxostat in treatment of patients with CKD and hyperurcemia to reduce the sUA level and analyze its influence on glomerular filtration rate (GFR). Materials and methods. The study included 45 CKD patients (stages 3b-5) without other severe/decompensated diseases and contraindications to the allopurinol/febuxostat. All patients underwent a comprehensive clinical and laboratory examination, and were divided into the study groups: Group I (28 patients, 61.3±3.2 y.o., CKD3b-12, CKD4-10, on hemodialysis-6 patients) received febuxostat, Group II (24 patients, 60.7Ѓ}4.1 y.o., CKD3b-9, CKD4-10, on hemodialysis – 5 patients) took allopurinol. Results. Achievement of the target level of sUA was significantly often registered in Group I: after 1 month – in 45.5% (in group II – in 15.9%, p<0.001); after 3 months – in 67.5% (in group II – 21.2% p<0.01); after 6 months, these figures were 90% and 37.1%, respectively (p<0.01). sUA level <300 μmol/l was accompanied by significant positive GFR changes in group I patients; in group II there was a gradual progression of GFR deterioration in 31.8% of patients. Conclusions. In patients with pre-dialysis stages of CKD febuxostat demonstrates renoprotective abilities. Use of febuxostat in patients with CKD stage 3b-4 and in patients on hemodialysis is safe and more effective for target sUA level achievement than the use of allopurinol.

POSSIBILITIES OF RENOPROTECTION IN PATIENTS WITH CHRONIC KIDNEY DISEASE AND HYPERURICEMIA

OBJECTIVE

The aim: To determine efficacy and safety of allopurinol and febuxostat in treatment of patients with CKD to reduce the sUA level and analyze its influence on glomerular filtration rate (GFR).

PATIENTS AND METHODS

Materials and methods: The study included 45 CKD patients (stages 3b-5) without other severe/decompensated diseases and contraindications to the allopurinol/febuxostat. All patients underwent a comprehensive clinical and laboratory examination, and were divided into the study groups: Group I (28 patients, 61,3±3,2 y.o., CKD3b-12, CKD4-10, on hemodialysis-6 patients) received febuxostat, Group II (24 patients, 60,7±4,1y.o., CKD3b-9, CKD4-10, on hemodialysis -5 patients) took allopurinol.

RESULTS

Results: Achievement of the target level of sUA was significantly often registered in Group I: after 1 month - in 45.5% (in group II - in 15.9%, p<0.001); after 3 months - in 67.5% (in group II - 21.2% p<0.01); after 6 months, these figures were 90% and 37.1%, respectively (p<0.01). sUA level <300 μmol/l was accompanied by significant positive GFR changes in group I patients; in group II there was a gradual progression of GFR deterioration in 31.8% of patients.

CONCLUSION

Conclusions: In patients with pre-dialysis stages of CKD febuxostat demonstrates renoprotective abilities. Use of febuxostat in patients with CKD stage 3b-4 and in patients on hemodialysis is safe and more effective for target sUA level achievement than the use of allopurinol.