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

Association between Glycosylated Hemoglobin and Serum Uric Acid: A US NHANES 2011-2020

Background

Serum uric acid (SUA) and glycosylated hemoglobin (HbA1c) were closely related to the body's metabolism. This study aimed to investigate the relationship between HbA1c and SUA in adults.

Methods

This study selected 7293 participants aged ≥20 from 2011 to 2020 in the National Health and Nutrition Examination Survey (NHANES). The multivariate linear regression model was used to test the association between HbA1c and SUA. Subgroup analysis was performed according to age, gender, race, and body mass index (BMI). This study solved the relationship between HbA1c and SUA by fitting a smooth curve. Finally, the inflection point in the nonlinear relationship was calculated by the recursive algorithm, and the relationship between HbA1c and SUA on both sides of the inflection point was analyzed by the two-segment piecewise linear regression model.

Results

All 7293 participants found a negative correlation between HbA1c and SUA by completely adjusting the model (β = -7.93 and 95% CI: -9.49--6.37). In addition, when this study was stratified by gender, age, race, and BMI status, this negative correlation was still statistically significant. In the subgroup analysis, we found that the relationship between the two had different results due to gender differences. In men, HbA1c had a significant negative correlation with SUA. However, in women, the HbA1c value was positively correlated with SUA before 6.8%, and the HbA1c value was negatively correlated with SUA after 6.8%, which indicates that the relationship between HbA1c and SUA in women has changed in prediabetes and diabetes.

Conclusion

This study shows that HbA1c is positively correlated with SUA in American adults before 7%. There is a negative correlation after the HbA1c value of 7%.

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.

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.

Gender Difference in the Association of Hyperuricemia with Insulin Resistance and beta-cell Function in Nondiabetic Korean Adults: The 2019 Korea National Health and Nutrition Examination Survey

AIMS

This study was conducted to assess the association of uric acid (UA) with the homeostasis model assessment of insulin resistance (HOMA-IR) and beta-cell function (HOMA-B) by gender in nondiabetic Korean adults.

MATERIALS AND METHODS

The study was carried out using data from the 2019 Korean National Health and Nutrition Examination Survey and included nondiabetic Korean men, premenopausal women, and postmenopausal women aged 20 years or older.

RESULTS

First, after adjusted for the related variables (excluding obesity), the prevalence of hyperuricemia (UA ≥ 7.0 mg/dL in men or UA ≥ 6.0 mg/dL in women) was positively associated with the quartiles of HOMA-IR and HOMA-B in men, premenopausal women, and postmenopausal women. Second, when further adjusted for obesity, hyperuricemia was positively associated with the quartiles of HOMA-IR and HOMA-B in men and postmenopausal women but not in premenopausal women. Third, after adjusted for the related variables (including obesity), UA level was positively associated with the quartiles of HOMA-IR and HOMA-B in men and postmenopausal women but not in premenopausal women.

CONCLUSIONS

hyperuricemia is positively associated with insulin resistance and beta-cell function in nondiabetic Korean men and postmenopausal women but not in premenopausal women.

Interaction of sex and diabetes on the association between hemoglobin glycation index, hemoglobin A1c and serum uric acid

BACKGROUND

Hemoglobin glycation index (HGI), which is calculated by blood glucose and hemoglobin A1c(HbA1c), reflects the individual discrepancy in HbA1c. This study aimed to investigate the association between HGI/HbA1c and serum uric acid(SUA) stratified by sex and diabetes.

METHODS

The study recruited 33772 participants who underwent physical examinations between April 2016 and August 2021 in Beijing Chao-Yang Hospital. A random subsample of 3000 subjects was utilized to calculate the formula of HGI and data of the remaining 30772 participants were used for analysis. HGI and HbA1c were categorized according to quartiles (Q1, Q2, Q3, Q4), using Q1 as the reference. We used multiple linear regression and restricted cubic splines for data analysis.

RESULTS

30772 participants with a mean age of 44.4 years old were included in the analysis, 48.6% (N = 14944) of which were female and 7.7% (N = 2363) with diabetes. Associations of HGI, HbA1c and SUA were modified by sex and diabetes. The relationship between SUA levels and HGI was positive in women without diabetes, with one unit increase in HGI associating with an 11.3 μmol/L increase in SUA (P < 0.001) after adjusting for other confounders. On average, each one-unit increase in HbA1c was associated with a 14.3 μmol/L decrease in SUA in women with diabetes, a 14.9 μmol/L decrease in SUA in men with diabetes, and a 16.5 μmol/L increase in SUA in women without diabetes (all P < 0.001). The SUA levels in men without diabetes showed a bell-shaped relation with HbA1c, increasing as the HbA1c rose to around 5.7% and then falling with a further increase of HbA1c (P < 0.001).

CONCLUSIONS

SUA levels were inversely correlated with HbA1c in diabetic patients, also in men with prediabetes (HbA1c ≥ 5.7%), but positively correlated with HbA1c and HGI in women without diabetes. Glycemic control may help to reduce the risk of hyperuricemia in non-diabetes women.

Correlation between serum C-peptide-releasing effects and the risk of elevated uric acid in type 2 diabetes mellitus

Our study aimed to investigate the C-peptide-releasing effect associated with the risk of elevated serum uric acid (SUA) levels in patients with type 2 diabetes mellitus (T2DM). In the cross-sectional study, 345 patients with T2DM hospitalized at the First Affiliated Hospital of Harbin Medical University were consecutively enrolled, and their baseline data were collected. The study design used two parameters for C-peptide releasing effects: the multiplication effect of 1 h postprandial C-peptide to fasting C-peptide ratio (1hCp/FCp) and 2hCp/FCp; the incremental effect of 1hCp minus FCp (1hΔCp) and 2hΔCp. The patients with T2DM in the upper quartiles of SUA had higher FCp, 1hCp, 1hΔCp, 2hCp, and 2hΔCp. Multiple linear regression analysis revealed that after adjusting all the confounding factors, the serum C-peptide including 1hCp (β = 5.14, p = 0.036), 1hΔCp (β = 7.80, p = 0.010), 2hCp (β = 4.27, p = 0.009) and 2hΔCp (β = 5.20, p = 0.005) were still positively correlated with SUA levels in patients with T2DM. In female patients, only the 2hCp (β = 4.78, p = 0.017) and 2hΔCp (β = 5.28, p = 0.019) were associated with SUA level; however, in male patients, no C-peptide parameter was associated with SUA levels in T2DM (all p > 0.05). Within a certain range, the elevated SUA levels might be associated with the better C-peptide incremental effect of islet β cell function in T2DM, especially in female patients.

Metabolomics-based evidence of the hypoglycemic effect and alleviation of diabetic complications by Ficus racemosa fruit in diabetic mice

The hypoglycemic and metabolic effects of Ficus racemosa fruit were studied in diabetic mice, and its potential mechanisms of hypoglycemic activity and its alleviation of diabetic complications were explored using...

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

PURPOSE

Higher serum levels of uric acid (SUA) are associated with an increased risk of developing type 2 diabetes. Meanwhile, insulin resistance and beta-cell dysfunction are critical factors that mediate the progression from normal glucose tolerance to impaired fasting glucose (IFG) and type 2 diabetes. We aimed to investigate the association between SUA levels and insulin resistance and beta-cell dysfunction in individuals without diabetes, thus explicating the role of uric acid in the early stage of the natural history of type 2 diabetes.

PATIENTS AND METHODS

We used cross-sectional data from the China Health and Nutrition Survey to examine the association. Insulin resistance and beta-cell dysfunction were estimated using the homeostasis model assessment of insulin resistance (HOMA-IR) index and homeostasis model assessment of beta-cell function (HOMA-beta) index, respectively. The associations were analyzed by using partial correlation analysis and multivariate logistic regressionl analysis.

RESULTS

SUA levels were positively associated with fasting glucose, fasting insulin, HOMA-IR in the total population. After adjustment for age, drinking, smoking, living area, daily dietary nutrient intake, body mass index (BMI), estimated glomerular filtration rate (eGFR), hypertension, and dyslipidemia, compared with participants in the lowest quartile of SUA, the adjusted odds ratios for the fourth quartiles were 1.56(1.09-2.24) for IFG, 1.51(1.27-1.78) for insulin resistance, and 1.06(0.88-1.27) for beta-cell dysfunction. In the subgroup analysis, no interactions were found between serum uric acid and age, drinking status, smoking status, BMI, hypertension, or dyslipidemia (all p for interaction>0.05).

CONCLUSION

In nondiabetic individuals, SUA levels are independently associated with IFG and insulin resistance, while no significant association exists between SUA and beta-cell dysfunction.

The association between serum uric acid and diabetic complications in patients with type 2 diabetes mellitus by gender: a cross-sectional study

BACKGROUND

The relationship between serum uric acid (SUA) and several diabetic complications or co-morbidities remains a matter of debate. The study aims to explore the association between SUA levels and the prevalence of non-alcoholic fatty liver disease (NAFLD), diabetic retinopathy (DR), diabetic nephropathy (DN) and diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 2,809 participants (1,784 males and 1,025 females) were included in this cross-sectional study. Clinical characteristics and the prevalence of each of the four diseases were analyzed based on gender-specific quartiles of SUA levels. The Pearson correlation analysis and linear-regression analysis were used to access the correlation between SUA levels and clinical characteristics. Furthermore, a binary logistic regression analysis was carried out to determine whether SUA was an independent risk factor for each of the four complications.

RESULTS

SUA levels were positively correlated to BMI, BUN, Scr and TG, but negatively associated with eGFR, HDL, FBG, 2h-PG and HbA1c% for the patients with T2DM. The prevalence of NAFLD and DN, but not DR or DPN, were increased with SUA levels from the first to the fourth quartile. Binary logistic regression further disclosed that SUA was an independent risk factor for NAFLD (ORs Male = 1.002, ∗ P = 0.0013; ORs Female = 1.002, ∗ P = 0.015) and DN (ORs Male = 1.006, ∗ P < 0.001; ORs Female = 1.005, ∗ P < 0.001), but not for DR and DPN. After adjustment for the confounders, SUA levels were significantly associated with NAFLD within the 3rd (ORs = 1.829, P = 0.004) and 4th quartile (ORs = 2.064, P = 0.001) for women, but not independently associated with SUA for man. On the other hand, our results revealed increased prevalence of DN for SUA quartile 2 (ORs = 3.643, P = 0.039), quartile 3 (ORs = 3.967, P = 0.024) and quartile 4 (ORs = 9.133, P < 0.001) in men; however, SUA quartiles were significantly associated with DN only for quartile 4 (ORs = 4.083, P = 0.042) in women.

CONCLUSION

For patients with T2DM, elevated SUA concentration is an independent risk factor for the prevalence of NAFLD and DN after adjustment for other indicators, but not DR or DPN.

Urine Uric Acid Excretion Levels are Positively Associated with Obesity and Abdominal Obesity in Type 2 Diabetes Patients without Chronic Kidney Disease

PURPOSE

We aimed to investigate whether urine uric acid excretion (UUAE) levels are associated with obesity and abdominal obesity in patients with type 2 diabetes (T2D).

METHODS

There were 2785 type 2 diabetic patients in this cross-sectional study. Obesity was defined as BMI ≥ 25 kg/m², and abdominal obesity was defined as waist circumference (WC) ≥90 cm for men and WC ≥ 80 cm for women based on World Health Organization (WHO) recommendations for Asians. Chronic kidney disease (CKD) was defined as the estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m² and/or urinary albumin excretion (UAE) ≥300 mg/24h. 24-h UUAE was determined enzymatically using a single 24-hour urine collection. All the subjects were stratified into quartiles based on UUAE levels. Both obesity and abdominal obesity were compared among the UUAE quartile groups, respectively. Furthermore, the associations of UUAE with obesity and abdominal obesity were analyzed in both CKD and non-CKD patients, respectively.

RESULTS

There was an obvious increased trend in both obesity prevalence (36.2%, 41.5%, 46.3%, and 63.4%, respectively, p < 0.001 for trend) and abdominal obesity prevalence (58.1%, 61.2%, 64.7%, and 75.8%, respectively, p < 0.001 for trend) in patients with T2D across the UUAE quartiles after controlling for age, sex and diabetes duration. Multiple logistic regression analyses revealed independent associations between UUAE quartiles and obesity (p < 0.001) and abdominal obesity (p < 0.001) in all patients. However, UUAE was significantly associated with obesity and abdominal obesity only in the T2D patients without CKD (p < 0.001 in model 1, model 2, model 3 and model 4, respectively).

CONCLUSION

Increased UUAE levels were significantly associated with the presence of obesity, especially abdominal obesity in T2D patients without CKD.

Distinct uric acid trajectories are associated with incident diabetes in an overweight Chinese population

AIM

To explore uric acid (UA) trajectories in different body mass index (BMI) populations and to determine their associations with incident diabetes.

METHODS

A total of 4566 adults without diabetes in 2011 were enrolled. All participants underwent a medical examination every year until 2016, and were classified into three subgroups based on BMI: non-obese (BMI<24kg/m²); overweight (BMI ≥24kg/m² but<28kg/m²); and obese (BMI ≥28kg/m²). Distinct UA trajectories were identified through group-based trajectory modelling (GBTM). Cox proportional-hazards models were applied to evaluate the associations between UA trajectories and risk of incident diabetes.

RESULTS

UA trajectories were identified in the three BMI subgroups: 'low' (42.4% in non-obese, 22.1% in overweight, 22.0% in obese); 'moderate' (32.5%, 41.1%, 34.8%); 'moderate-high' (18.6%, 29.5%, 30.8%); and 'high' (6.5%, 7.3%, 12.4%). After a 5-year follow-up, 170 (3.7%) participants had developed diabetes. The prevalence of new-onset diabetes increased progressively with the higher UA trajectories in the BMI groups (P values<0.05). Whereas compared with the low trajectory, a significant association between a high UA trajectory and incidence of diabetes was observed only in the overweight population [hazard ratio (HR): 6.95, 95% confidence interval (CI): 1.90-25.45], with no significant associations found in either the non-obese (HR: 0.67, 95% CI: 0.13-3.52) or obese (HR: 0.40, 95% CI: 0.06-2.64) populations, in the fully adjusted model.

CONCLUSION

Higher UA trajectories are significantly associated with an increased risk of incident diabetes, thereby suggesting that monitoring UA trajectories over time may assist in the identification of prediabetes and diabetes, particularly in the overweight population.

C-Peptide: A Mediator of the Association Between Serum Uric Acid to Creatinine Ratio and Non-Alcoholic Fatty Liver Disease in a Chinese Population With Normal Serum Uric Acid Levels

BACKGROUND

The data on the relationship between normal-ranged serum uric acid (SUA), β-cell function, and non-alcoholic fatty liver disease (NAFLD) are complicated and insufficient. Moreover, uric acid is excreted by kidney, and SUA levels may be affected by renal function. Thus, we introduced a renal function-normalized index [serum uric acid to creatinine ratio (SUA/Cr)] into the study and explored the association between SUA/Cr, C-peptide and NAFLD in a Chinese population with normal SUA levels by a cross-sectional analysis.

MATERIALS AND METHODS

A total of 282 individuals with normal SUA levels and different glucose tolerance status from a diabetes project were included in the study (mean age = 53.7± 10.5 years; women = 64.50%). NAFLD was diagnosed by abdominal ultrasonography (NAFLD, n=86; without NAFLD, n=196). Trapezoid formula was used to calculate area under the curve of C-peptide (AUC_CP) from 4 points (including 0, 30,60, and 120min) during 2-h oral glucose tolerance test. Spearman correlation analysis was used to explore the correlation between SUA/Cr, AUC_CP and NAFLD risk factors. Multiple logistic regression analysis was used to explore the association between SUA/Cr or AUC_CP and NAFLD. Mediation analysis was used to explore whether AUC_CP mediated the association between SUA/Cr and NAFLD.

RESULTS

Individuals with NAFLD had significantly higher SUA/Cr and AUC_CP than those without NAFLD(P<0.05). Spearman correlation analysis showed that both SUA/Cr and AUC_CP were significantly associated with many NAFLD risk factors, and SUA/Cr was positively correlated with AUC_CP (P<0.05). Multiple logistic regression analysis indicated that SUA/Cr and AUC_CP were positively associated with NAFLD incidence (P<0.05). Medication analysis indicated that SUA/Cr had a significant direct effect on NAFLD (β =0.5854, 95% CI: 0.3232-0.8966), and AUC_CP partly mediated the indirect effect of SUA/Cr on NAFLD incidence (β =0.1311, 95% CI: 0.0168-0.4663).

CONCLUSIONS

SUA/Cr was positively associated with NAFLD incidence, and AUC_CP partly mediated the association in a Chinese population with normal SUA levels. Thus, we should pay more attention to high-normal SUA and C-peptide levels due to their predictive power in NAFLD incidence.