Effects of Body Mass Index, Glycemic Control, and Hypoglycemic Drugs on Serum Uric Acid Levels in Type 2 Diabetic Patients

Association between Polycystic Ovarian Syndrome, Impaired Kidney Function and Hyperuricaemia: A Systematic Review and Meta-analysis

Background

Polycystic ovarian syndrome (PCOS) is a gynaecological problem affecting women within reproductive age, accompanied by several metabolic anomalies, thus leading to alteration in kidney function and hyperuricaemia. Due to the high prevalence of cardiometabolic factors in PCOS, there is a need to anticipate an increased number of kidney impairments amongst these women.

Objectives

This review aims to investigate the potential link between PCOS, impaired kidney function, and elevated uric acid levels. By elucidating this association, we hope to provide clinicians with a tool to stratify the risk of kidney disease in women diagnosed with PCOS, based on readily available kidney function parameters.

Materials and Methods

The recommendations used for the analysis were outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Subsequently, eligible studies were identified using several databases (MEDLINE, ProQuest and EBSCOhost) between 1996 and 2022, with a total of 13 studies included. Serum uric acid, serum creatinine, as well as estimated glomerular filtration rate (eGFR) were evaluated as the outcome of interest. Quality assessment for cohort, case-control and cross-sectional studies was conducted utilising the Newcastle-Ottawa Scale, while Review Manager 5.4 was utilised for meta-analysis.

Results

Uric acid was significantly higher in women with PCOS (mean difference [MD] = 0.70, 95% confidence interval [CI] [0.45-0.95], P < 0.00001). Meanwhile, serum creatinine and eGFR were statistically similar in each group (MD = 0.08, 95% CI [-0.05-0.21], P = 0.22 and MD = 3.54, 95% CI [-4.53-11.61], P = 0.39, respectively).

Interpretation

This review showed that PCOS was significantly associated with elevated uric acid. However, no significant difference was found between eGFR and creatinine levels compared to healthy controls. Routine uric acid assessment in PCOS patients is recommended as a simple tool for risk stratification.

Limitations

No body mass index (BMI) subgroup analysis was done due to limited BMI reporting in our included studies. Quantitative analysis of all kidney function parameters was also limited by sparse data on urea and albumin.

PROSPERO Registration Number

CRD42023410092 (02 April 2023).

Serum uric acid and the risk of gestational diabetes mellitus: a systematic review and meta-analysis

AIMS

Serum uric acid (SUA) is considered as a risk factor for gestational diabetes mellitus (GDM). However, current studies showed inconsistent results. This study aimed to explore the relationship between SUA levels and GDM risk.

METHODS

Eligible studies were retrieved from PubMed, Web of Science, Embase, China National Knowledge Infrastructure, and Wanfang databases up to November 1, 2022. The pooled standardized mean difference (SMD) and 95% confidence interval (CI) were used to represent the difference in SUA levels between GDM women and controls. The combined odds ratios (OR) and 95% CI were applied to assess association between SUA levels and GDM risk. Subgroup analyses were conducted on study continents, design, and quality, detection time of SUA, and GDM diagnostic criteria.

RESULTS

Totally 11 studies including five case-control and six cohort studies, in which 80,387 pregnant women with 9815 GDM were included. The overall meta-analysis showed that the mean SUA level in GDM group was significantly higher than in controls (SMD = 0.423, 95%CI = 0.019-0.826, p = .040, I² = 93%). Notably, pregnant women with elevated levels of SUA had a significantly increased risk of GDM (OR = 1.670, 95%CI = 1.184-2.356, p = .0035, I² = 95%). Furthermore, subgroup analysis performed on the detection time of SUA showed a significant difference in the association between SUA and GDM risk within different trimesters (1st trimester: OR = 3.978, 95%CI = 2.177-7.268; 1st to 2nd trimester: OR = 1.340, 95%CI = 1.078-1.667; p between subgroups <.01).

CONCLUSIONS

Elevated SUA was positively associated with GDM risk, particularly in the 1st trimester of pregnancy. Further studies with high quality are required to validate the findings of this study.

Serum Uric Acid and Diabetes: From Pathophysiology to Cardiovascular Disease

Hyperuricemia, has been traditionally related to nephrolithiasis and gout. However, it has also been associated with the development of type 2 diabetes mellitus (T2DM) and cardiometabolic and cardiovascular diseases. Pathophysiologically, elevated serum uric acid (SUA) levels may be associated with abnormal lipid and glucose metabolism. In this narrative review, we consider the associations between hyperuricemia, hyperglycemia, atherosclerosis and thrombosis. Furthermore, we comment on the available evidence linking elevated SUA levels with the incidence and outcomes of coronary heart disease, stroke, peripheral artery disease and non-alcoholic fatty liver in subjects with T2DM. The effects of antidiabetic drugs (e.g. metformin, pioglitazone, sulfonylureas, dipeptidyl peptidase 4 inhibitors, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors and insulin) on SUA concentrations are also reviewed.

Effects of a Behavioral Weight Loss Intervention and Metformin Treatment on Serum Urate: Results from a Randomized Clinical Trial

Background: Lower body mass index (BMI) has been associated with lower serum urate (SU), but only in observational studies. We sought to determine the effects of behavioral weight loss and metformin treatment on SU in a randomized trial. Methods and Findings: The Survivorship Promotion In Reducing IGF-1 Trial (SPIRIT) was a parallel three-arm randomized controlled trial of overweight/obese adult cancer survivors without gout at a single center in Maryland, United States. Participants were randomized to: (1) coach-directed weight loss (behavioral telephonic coaching), (2) metformin (up to 2000 mg daily), or (3) self-directed weight loss (informational brochures; reference group). SU and BMI were assessed at baseline and at 3, 6, and 12 months post-randomization. The 121 participants had a mean ± standard deviation (SD) age of 60 ± 9 years, 79% were female, and 45% were Black. At baseline, BMI was 35 ± 5 kg/m², and SU was 5.6 ± 1.3 mg/dL. Compared to the self-directed group, at 12 months, the coach-directed group reduced BMI by 0.9 kg/m² (95% confidence interval (CI): -1.5, -0.4) and metformin reduced BMI by 0.6 kg/m² (95% CI: -1.1, -0.1). However, compared to the self-directed group, the coach-directed group unexpectedly increased SU by 0.3 mg/dL (95% CI: 0.05, 0.6), and metformin non-significantly increased SU by 0.2 mg/dL (95% CI: -0.04, 0.5); these effects were attenuated when analyses included change in estimated glomerular filtration rate (eGFR). Conclusions: In this randomized trial of cancer survivors without gout, reductions in BMI either increased or did not change SU, potentially due to effects on eGFR. These results do not support a focus on BMI reduction for SU reduction; however, long-term studies are needed. ClinicalTrials.gov Registration: NCT02431676.

Vitamin D3 potentiates the nephroprotective effects of metformin in a rat model of metabolic syndrome: role of AMPK/SIRT1 activation and DPP-4 inhibition

The current study aimed to investigate the molecular mechanisms of metformin and vitamin D3-induced nephroprotection in a metabolic syndrome (MetS) rat model, evaluating the capacity of vitamin D3 to potentiate metformin action. MetS was induced by 10% fructose in drinking water and 3% salt in the diet. After 6 weeks, serum lipid profile and uric acid were measured, an oral glucose tolerance test (OGTT) was performed, and kidney function was investigated. In conjunction with the same concentrations of fructose and salt feeding, MetS rats with significant weight gain, dyslipidemia, hyperuricemia, and dysglycemia were treated orally with metformin (200 mg/kg), vitamin D3 (10 µg/kg), or both daily for 6 weeks. At the end of the study period, anthropometrical parameters were recorded, OGTT was reperformed, urine and blood samples were collected, and tissue samples were harvested at sacrifice. MetS rats showed dramatically declined renal function, enhanced intrarenal oxidative stress and inflammation, and extravagant renal histopathological damage with interstitial fibrosis. Metformin and vitamin D3 significantly reversed all the aforementioned deleterious effects in MetS rats. The study has verified the nephroprotective effects of metformin and vitamin D3 in MetS, accentuating the critical role of AMP-activated protein kinase/sirtuin-1 activation and dipeptidyl peptidase-4 inhibition. Given the synergistic effects of the combination, vitamin D3 is worth being investigated as an additional therapeutic agent for preventing MetS-induced nephropathy.

Relationship between hyperuricemia and serositis in patients with lupus nephritis

PURPOSE

To investigate the clinical and pathological characteristics of lupus nephritis (LN) patients with serositis and analyse the relationship between serositis and hyperuricemia (HUA) in LN patients in northeast China.

METHODS

The data of patients with LN diagnosed by renal biopsy in our hospital from April 2013 to May 2020 were retrospectively analyzed. The differences between the non-serositis and serositis groups were compared by t tests and Chi-square test. Factors with P < 0.05 in the univariate analyses were investigated further using binary logistic regression analysis to investigate the independent risk factors of serositis in patients with LN.

RESULTS

LN patients with serositis were more likely to have fever, hypertension, neuropsychiatric and hematological involvement than those without serositis (P < 0.05). Compared with the non-serositis group, LN patients with serositis were prone to have HUA, high D-dimer, high triglycerides, and had significant differences in the levels of plasma albumin (Alb), estimated glomerular filtration rate (eGFR), erythrocyte sedimentation rate, C-reactive protein, complement C3, 24-h urinary protein, pathological types, pathological score and SLEDAI score. Logistic regression analysis showed that HUA was one of risk factors for serositis in LN patients. The rate of complete remission in LN patients with serositis was significantly lower (P < 0.05) and the rate of no remission and mortality were significantly higher (P < 0.05) than LN patients without serositis.

CONCLUSION

LN patients with serositis had more severe clinical and pathological manifestations, higher systemic lupus erythematosus (SLE) activity and worse prognosis. Hyperuricemia is associated with serositis in LN patients.

Sildenafil alters biogenic amines and increases oxidative damage in brain regions of insulin-hypoglycemic rats

The aim of the present study was to determine the effect of sildenafil on dopamine, 5-hydroxyindol acetic acid (5-HIAA) and selected biomarkers of oxidative stress in the brain of hypoglycemic rats. The animals were treated intraperitoneally as follows: group 1 (control), saline solution; group 2, insulin (10 U per rat or 50 U kg-1); group 3, insulin + single dose of sildenafil (50 U kg-1 + 50 mg kg-1); group 4, insulin + three doses of sildenafil every 24 hours (50 U kg-1 + 50 mg kg-1). In groups 2, 3 and 4, insulin was administered every 24 hours for 10 days. Blood glucose was measured after the last treatment. On the last day of the treatment, the animals´ brains were extracted to measure the levels of oxidative stress markers [H2O2, Ca2+,Mg2+-ATPase, glutathione and lipid peroxidation (TBARS)], dopamine and 5-HIAA in the cortex, striatum and cerebellum/medulla oblongata by validated methods. The results suggest that administration of insulin in combination with sildenafil induces hypoglycemia and hypotension, enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines. Administration of insulin and sildenafil promotes biometabolic responses in glucose control, namely, it induces hypoglycemia and hypotension. It also enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines.

Consumption of Cooked Common Beans or Saponins Could Reduce the Risk of Diabetic Complications

Several risks for diseases, such as atherosclerosis, renal diseases, and diabetes, have inextricably been linked with obesity. Nowadays, this health-risk-laden disease is being managed with assorted types of drugs, some of which guarantee modest benefits. The chronic inflammatory effect of obesity has a negative effect in insulin signaling, a situation attributable to insulin resistance that culminates in high blood sugar inputs seen in diseases such as type 2 diabetes and metabolic syndrome. Food such as beans with different bioactive compounds could reduce the risk of diabetic complications. Demand for bean products is growing because of its robust contents of several health-promoting components, eg, saponins. Saponins are characterized by containing lower glucose and cholesterol levels and have been doted with antioxidant activities, as well as anti-inflammatory and anti-diabetic effects. In this writing, the attributes of saponins in providing substantial health and nutritional benefits in humans, as well as in improving and ameliorating diabetic complications, were reviewed.

Serum uric acid as a risk factor of all-cause mortality and cardiovascular events among type 2 diabetes population: Meta-analysis of correlational evidence

AIMS

To explore the association between serum uric acid (SUA) level and the risk of cardiovascular complications and all-cause mortality rates among individuals with type 2 diabetes.

METHODS

Web of Science and PubMed database were searched for studies reported associations between SUA level and cardiovascular complications and all-cause mortality among individuals with type 2 diabetes. Hazard ratios (HRs) were independently extracted by two investigators and synthesized through meta-analysis across selected studies.

RESULTS

6 (n = 11,750 patients), 4 (n = 3044 patients) and 2 studies (n = 7792 patients) were identified reporting associations between SUA level and all-cause mortality, coronary heart disease (CHD) and stroke respectively. HR for all-cause mortality, CHD, and stroke per 59 μmol/l increase was 1.06 (95% CI: 1.03, 1.09), 1.09 (95% CI: 0.94, 1.26) and 1.19 (95% CI: 1.08, 1.31), respectively.

CONCLUSIONS

Overall, the SUA level was associated with a higher risk of all-cause mortality and stroke. We found no significant association between SUA level and CHD among type 2 diabetes population.

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.