Effects of Uric Acid-Lowering Treatment on Glycemia: A Systematic Review and Meta-Analysis

Association of xanthine oxidoreductase inhibitor use with insulin secretory capacity in patients with type 2 diabetes

AIM/INTRODUCTION

Xanthine oxidoreductase (XOR) inhibitor treatment, which reduces reactive oxygen species (ROS) production and increases adenosine triphosphate (ATP) synthesis, has been reported to improve glycemic control. The possible protective effects of XOR inhibitor treatment on insulin secretory capacity were investigated in patients with type 2 diabetes.

MATERIALS AND METHODS

This retrospective cross-sectional study included 428 patients with type 2 diabetes. Insulin secretory capacity was assessed based on fasting serum C-peptide concentration (CPR) and C-peptide index (CPI) in all subjects, while insulin resistance in non-insulin users (n = 312) was determined using the homeostasis model assessment of insulin resistance (HOMA-IR) index.

RESULTS

Median values for CPR and CPI in all subjects were 2.4 ng/mL and 1.5, respectively, while that for HOMA-IR in non-insulin users was 3.2. The XOR inhibitor users (n = 72) had significantly (P < 0.001) higher CPR and CPI levels than non-users (n = 356). Multivariable regression analyses showed XOR inhibitor use was positively associated with CPR (β = 0.153, P = 0.001) and CPI (β = 0.144, P = 0.001). Similar results were observed in propensity score analyses. In subgroup analyses of patients with a preserved estimated glomerular filtration rate (≥60 mL/min/1.73 m2) and non-insulin users, these associations remained significant. Furthermore, the associations were significant in patients with lower (≤6.0 mg/dL) but not with higher (>6.0 mg/dL) uric acid levels (P for interaction <0.05). On the other hand, XOR inhibitor use showed no significant association with HOMA-IR.

CONCLUSIONS

The results of XOR inhibitor treatment, especially a sufficient reduction in serum uric acid level, may provide protective effects on insulin secretory capacity in patients with type 2 diabetes.

Association of platelet to high-density lipoprotein cholesterol ratio with hyperuricemia

The platelet/high-density lipoprotein ratio (PHR) has been identified as a significant indicator of inflammation and a hypercoagulable state, demonstrating a strong link with the severity of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS). However, its correlation with hyperuricemia has not yet been documented. This study utilized a cross-sectional design, analyzing data collected from the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016 in the United States. The platelet/high-density lipoprotein ratio (PHR) was determined by dividing the number of platelets (PLT) by the level of high-density lipoprotein cholesterol (HDL-C). We employed multivariable logistic regression analyses, generalized additive models, and subgroup analyses to investigate the correlation between PHR and hyperuricemia. The study revealed a hyperuricemia prevalence of 18.56%. Analysis indicated a significant positive correlation between PHR and the risk of hyperuricemia (OR 1.11, 95% CI 1.08, 1.14). This correlation remained consistent across different subgroups including age, ethnicity, gender, and body mass index (BMI). Smooth curve fitting demonstrated a saturation effect between PHR and the risk of hyperuricemia. PHR is positively correlated with hyperuricemia and may serve as a novel biomarker for predicting the onset of this condition. Additionally, targeted interventions to improve PHR might help reduce the incidence of hyperuricemia.

Correlation and influencing factors of neurophysiological examinations and serum uric acid in patients with diabetic peripheral neuropathy: an exploratory study

OBJECTIVE

This study aimed to investigate the correlation and influencing factors between neurophysiological examinations, serum uric acid (SUA), and glucose metabolism in patients with Diabetic Peripheral Neuropathy (DPN).

METHODS

A total of 114 patients with DPN who received treatment at the Endocrinology Department of our hospital from January 2022 to December 2023 were included. According to the median blood uric acid level, the patients were divided into high SUA group and low SUA group, and the demographic data, blood glucose indexes and motor nerve electrophysiological examination results of the two groups were compared.

RESULTS

The level of FPG and HbA1c was higher in the high SUA group. The motor nerve latency of the high SUA group was higher, the motor nerve amplitude and motor nerve conduction velocity of the high SUA group were lower than those of the low SUA group. SUA was positively correlated with motor nerve latency and negatively correlated with motor nerve amplitude and conduction velocity.

CONCLUSION

In DPN, high SUA levels are associated with poor glycemic control. With the increase in SUA levels, the motor nerve latency in patients with T2DM is prolonged, and amplitude and conduction velocity decrease, and high SUA is a risk factor and potential predictor of DPN.

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.

Uric acid and diabetes mellitus: an update

The relationship between diabetes mellitus (DM) and high serum uric acid is complex and controversial. Many epidemiological studies have reported a positive association, whereas others have reported an inverse association or none. In the pathogenesis of DM it is the intracellular urate that is more important than the extracellular and dissociation between the two is possible. Evidence suggests that high serum uric acid induces insulin resistance and beta cell failure in animal models. Reduction of intracellular uric acid can be achieved by dietary measures such as reducing fructose and salt intake, and uric acid-lowering drugs. We suggest that in the Western diet, these elements play a crucial role in pathogenesis of DM. To determine the precise and exact interrelationship between intracellular and extracellular uric acid, well-designed studies are required. Besides this, clinical trials are needed to determine whether intracellular and extracellular urate reduction will provide benefit in prevention and treatment of DM and complications associated with it.

Correlation between serum uric acid and body fat distribution in patients with MAFLD

BACKGROUND

Metabolic dysfunction associated with fatty liver disease (MAFLD) is often correlated with obesity and hyperuricemia. The present study aimed to determine the association between serum uric acid (SUA) and central fat distribution in patients with MAFLD.

METHODS

A total of 485 patients were classified into the following groups: (1) controls without MAFLD and hyperuricemia (HUA), (2) MAFLD with normal SUA, and (3) MAFLD with HUA. DUALSCAN HDS-2000 was used to measure visceral fat (VAT) and subcutaneous fat (SAT). Dual-energy X-ray absorptiometry (DEXA) was used to measure body fat distribution.

RESULTS

MAFLD patients with HUA had remarkably higher BMI, fasting insulin, OGIRT AUC, ALT, AST, TG, VAT, SAT, Adipo-IR, trunk fat mass, android fat, and total body fat than MAFLD patients with normal SUA (all p < 0.05). The increase in VAT, SAT, CAP, Adipo-IR, upper limbs fat mass, trunk fat mass, and android fat, as well as the percentage of MAFLD, were significantly correlated with the increase in SUA. The percentage of MAFLD patients with HUA increased significantly with increasing VAT or SAT, as determined by the Cochran-Armitage trend test (all p < 0.05). Furthermore, VAT (OR = 1.01 CI: 1.00, 1.03; p < 0.05) and adipo-IR (OR = 1.09 CI: 1.00, 1.19; p < 0.05) were associated with circling SUA in MAFLD after adjusting for sex, age, TG, TC, HOMA-IR, and BMI.

CONCLUSION

Abdominal fat promotes the co-existence of HUA and MAFLD, while weight loss, especially, decreasing VAT, is of great importance to decrease SUA levels and manage MAFLD.

A Systematic Review and Meta-Analysis of the Association between Uric Acid and Allantoin and Rheumatoid Arthritis

Alterations in the circulating concentrations of uric acid and its degradation product, allantoin, might account for the systemic pro-oxidant state and the increased cardiovascular risk in rheumatoid arthritis (RA). We sought to address this issue by conducting a systematic review and meta-analysis of the association between the plasma/serum concentrations of uric acid and allantoin and RA. We searched PubMed, Scopus, and Web of Science from inception to 20 June 2023 for studies comparing plasma/serum concentrations of uric acid and allantoin between RA patients and healthy controls. We assessed the risk of bias with the JBI Critical Appraisal Checklist for analytical studies and the certainty of evidence with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) Working Group system. In the 19 studies selected for analysis, there were non-significant differences in uric acid concentrations between RA patients and controls (standard mean difference, SMD = 0.11, 95% CI -0.07 to 0.30, p = 0.22; I2 = 87.9%, p < 0.001; low certainty of evidence). By contrast, the concentrations of allantoin were significantly higher in RA patients (SMD = 1.10, 95% CI 0.66 to 1.55, p < 0.001; I2 = 55.6%, p = 0.08; extremely low certainty of evidence). In meta-regression, a significant association was observed between the SMD of uric acid concentrations and body mass index, a risk factor for atherosclerosis and cardiovascular disease (t = 3.35, p = 0.007). Our study has shown a significant increase in the concentrations of the oxidative stress biomarker allantoin in patients with RA. Further research is warranted to investigate the interplay between uric acid, allantoin, redox balance, and cardiovascular disease in this group. (PROSPERO registration number: CRD42023441127).

Risk factors and management of hyperuricemia after renal transplantation

Hyperuricemia (HUA) is a common complication after renal transplantation. Currently, there is no uniform consensus on factors which increase the risk for and treatment of HUA in renal transplant recipients. The purpose of this review is to summarize current and proposed risk factors and strategies to manage HUA after renal transplantation in order to assist renal function protection and prolong graft survival time.

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.

Effects of allopurinol on renal function in patients with diabetes: a systematic review and meta-analysis

BACKGROUND/OBJECTIVE

Diabetes mellitus is a common "non-gout" disease with high incidence. Several studies have shown that serum uric acid level in patients with diabetes is higher than that in healthy individuals, and is accompanied by severe albuminuria and high serum creatinine (Scr). Recent clinical studies have found that uric acid-lowering therapy (such as allopurinol) could reduce urinary albumin excretion rates (UAER) and Scr, increase eGFR, and thus reduce kidney damage in patients with diabetes. Therefore, this meta-analysis [PROSPERO CRD42021274465] intended to evaluate the efficacy and safety of allopurinol in patients with diabetes mellitus.

METHODS

We thoroughly searched five electronic resource databases for randomized controlled trials (RCTs) that compared the efficacy and safety of allopurinol versus conventional treatment or placebo for the treatment of patients with diabetes mellitus. Predetermined outcomes were considered continuous variables, mean difference (MD) was used for the determination of effect size (standardized mean difference [SMD] was used to determine the effect size when there were different evaluation criteria in different articles), and the corresponding 95% confidence interval (CI) was calculated. All outcome measures were analyzed using a random-effects model for data analysis.

RESULTS

Ten eligible trials with a total of 866 participants were included in the meta-analysis. Allopurinol was more effective in decreasing serum uric acid (SUA) levels compared with conventional treatment (p = 0.0001) or placebo (p < 0.00001). Moreover, the levels of 24-hour urine protein were significantly lower in the allopurinol group (p < 0.00001). The subgroup analysis of Scr showed that the Scr of patients with an allopurinol treatment duration of fewer than six months was significantly lower than that of the control group (p = 0.03). No significant difference in adverse events (AEs) was identified between the treatment and control groups.

CONCLUSIONS

Our meta-analysis of RCTs showed that oral administration of allopurinol effectively reduced SUA levels in patients with diabetes, and patients' renal function was protected. More RCTs with larger sample sizes and higher quality are needed to clarify the role of allopurinol use in decreasing blood pressure, maintaining blood glucose levels, and improving renal function in patients with diabetes.

Effect of low dose allopurinol on glycemic control and glycemic variability in patients with type 2 diabetes mellitus: A cross-sectional study

Background

Type 2 diabetes mellitus (DM), gout, and asymptomatic hyperuricemia are inter-connected pathologies. Glycemic control (GC), involving a range of treatments is central to the management of DM, whereas allopurinol continues to be the most widely recommended urate lowering agent. Allopurinol has been shown to possess anti-oxidant properties: this study explores the potential effect of allopurinol on glucose homeostasis.

Methods

This is an observational study with a cross-sectional design performed on patients with type 2 diabetes mellitus (DM), recruited from centers in Saudi Arabia. Patients were divided into two groups; allopurinol users; (for gout or asymptomatic hyperuricemia) and a matching disease control group. Patient demographics, co-morbid conditions, biochemical tests, and pharmacological treatments were extracted from electronic records to investigate the effect of allopurinol therapy on Glycemic control (GC), as assessed by glycated haemoglobin (HbA1c as primary endpoint), and on parameters of glycaemic variability (GV) (secondary endpoints).

Results

A total of 194 patients with type 2 DM were recruited (97 in both groups). The two groups were matched for age, sex, and duration of DM: mean age: 59.4 years, 73% males, and 122 months in the allopurinol group vs 59.6 years, 73% males, and 113 months in the control group. Antidiabetic medications were matched between the two groups. In the allopurinol group, it was prescribed with a daily dose of 100 mg, for 77% of the patients, with median duration of 39.5 months. HbA1c values were; 6.90% (6.20, 7.80) in the allopurinol group vs 7.30% (6.60, 8.40) in the control group (P = 0.010). Parameters of GV were calculated from 3 consecutive fasting blood sugar (FBS) readings: variability independent of the mean (VIM) was 0.140 in the allopurinol group vs 0.987 in the control group (P < 0.001).

Conclusion

Concomitant low-dose allopurinol therapy in patients with type 2 DM was associated with modest but significant improvements in GC and GV.

Disordered Glucose Levels Are Associated with Xanthine Oxidase Activity in Overweight Type 2 Diabetic Women

Oxidative stress plays an important role in vascular complications observed in patients with obesity and Type 2 Diabetes (T2D). Xanthine oxidase (XO) breaks down purine nucleotides into uric acid and contributes to the production of reactive oxygen species (ROS). However, the relationship between XO activity and glucose homeostasis in T2D subjects with obesity is unclear. We hypothesized that disordered glucose levels are associated with serum XO activity in overweight women and men with T2D and without hyperuricemia. We studied serum XO activity in women and men with and without T2D. Our results show that serum XO activity was greater in T2D patients with body mass index (BMI) ≥ 25 kg/m2 than in those with BMI < 25 kg/m2 (p < 0.0001). Sex-based comparative analyses of overweight T2D patients showed that serum XO activity correlated with homeostasis model assessment of β-cell function (HOMA-β), fasting plasma glucose (FPG), and hemoglobin A1C in overweight T2D women but not in overweight T2D men. In addition, as compared to overweight T2D men, women had higher high-sensitivity C-reactive protein (hs-CRP) levels. However, overweight T2D men had higher XO activity and uric acid levels than women. Our results suggest that XO activity is higher in overweight T2D patients, especially in men, but is more sensitive to disordered glucose levels in overweight women with T2D.

Nutraceutical Prevention of Diabetic Complications—Focus on Dicarbonyl and Oxidative Stress

Oxidative and dicarbonyl stress, driven by excess accumulation of glycolytic intermediates in cells that are highly permeable to glucose in the absence of effective insulin activity, appear to be the chief mediators of the complications of diabetes. The most pathogenically significant dicarbonyl stress reflects spontaneous dephosphorylation of glycolytic triose phosphates, giving rise to highly reactive methylglyoxal. This compound can be converted to harmless lactate by the sequential activity of glyoxalase I and II, employing glutathione as a catalyst. The transcription of glyoxalase I, rate-limiting for this process, is promoted by Nrf2, which can be activated by nutraceutical phase 2 inducers such as lipoic acid and sulforaphane. In cells exposed to hyperglycemia, glycine somehow up-regulates Nrf2 activity. Zinc can likewise promote glyoxalase I transcription, via activation of the metal-responsive transcription factor (MTF) that binds to the glyoxalase promoter. Induction of glyoxalase I and metallothionein may explain the protective impact of zinc in rodent models of diabetic complications. With respect to the contribution of oxidative stress to diabetic complications, promoters of mitophagy and mitochondrial biogenesis, UCP2 inducers, inhibitors of NAPDH oxidase, recouplers of eNOS, glutathione precursors, membrane oxidant scavengers, Nrf2 activators, and correction of diabetic thiamine deficiency should help to quell this.

Elevated serum uric acid is a facilitating mechanism for insulin resistance mediated accumulation of visceral adipose tissue

OBJECTIVE

Serum uric acid (SUA) has been associated with cardiometabolic conditions such as insulin resistance (IR) and visceral adipose tissue (VAT) accumulation. Here, we aimed to clarify a unifying mechanism linking elevated SUA to IR and VAT.

METHODS

We conducted analyses in 226 subjects from the UIEM cohort with both euglycemic hyperinsulinemic clamp (EHC) and dual X-ray absorptiometry (DXA) measurements for IR and VAT accumulation and explored the role of SUA and adiponectin by developing a network of causal mediation analyses to assess their impact on IR and VAT. These models were then translated to two population-based cohorts comprising 6337 subjects from NHANES 2003-2004 and 2011-2012 cycles in the US and ENSANUT Medio Camino 2016 in Mexico, using HOMA2IR and adipoIR as indicators of peripheral and adipose tissue IR, and METS-VF as a surrogate for VAT accumulation.

RESULTS

SUA has a mediating role inside a bidirectional relationship between IR and visceral obesity, which was similar using either gold standard measurements or surrogate measures for IR and VAT. Furthermore, adiponectin acts as a linking mediator between elevated SUA and both peripheral IR and VAT accumulation. The proportion of the mechanism for IR-mediated (in either peripheral or adipose tissue) VAT accumulation was greater, compared to VAT-mediated IR accumulation (10.53% [9.23%-12.00%] to 5.44% [3.78%-7.00%]). Normal-range SUA levels can be used to rule-out underlying cardio-metabolic abnormalities in both men and women.

CONCLUSIONS

Elevated SUA acts as a mediator inside the bidirectional relationship between IR and VAT accumulation and these observations could be applicable at a phenotype scale.

Relation between Uric Acid Levels and Subclinical Hypothyroidism in Diabetic Patients

BACKGROUND AND AIM

Subclinical hypothyroidism (SCH) is frequently seen in diabetic patients. Elevated levels of uric acid (UA) were also reported in diabetic patients. No study assessed the relation between SCH and UA levels in diabetic patients. We aimed to evaluate this relation and the association of both conditions with other clinical and laboratory parameters in diabetic patients.

SUBJECTS AND METHODS

This cross-sectional study included 100 T2DM patients in addition to 50 age and sex matched healthy controls. Diabetic patients comprised 50 patients with SCH and 50 euthyroid patients. All participants were subjected to careful history taking, thorough clinical examination and standard laboratory work up. The performed investigations included fasting and postprandial blood sugar, fasting insulin levels, HbA1c levels, thyroid hormones (FT3, FT4 and TSH), renal profile and serum UA.

RESULTS

Comparison between the studied groups regarding serum UA levels revealed significantly higher levels in the diabetic group (5.4 ± 1.9 versus 4.2 ± 1.0 mg/dl, p<0.001). SCH + DM patients had significantly higher UA levels in comparison to DM group (6.1 ± 1.8 versus 4.8 ± 1.7 mg/dl, p<0.001) and control group (6.1 ± 1.8 versus 4.2 ± 1.0 mg/dl, p<0.001). SCH + DM patients had significantly higher HbA1c levels (8.9 ± 1.1 versus 7.6 ± 1.3 %, p<0.001), HOMA-IR (3.9 ± 0.8 versus 2.8 ± 1.0, p<0.001) and UA levels (6.1 ± 1.8 versus 4.8 ± 1.7, p<0.001). Correlation analysis identified a significant direct correlation between serum UA and HOMA-IR in DM + SCH patients (r=0.4,p=0.004). In univariate analysis, presence of SCH [OR (95% CI): 2.57 (1.07-6.15), p=0.034] and nephropathy [OR (95% CI): 4.57 (1.77-11.8), p=0.002] were significant predictors of higher (upper tertile) UA in the studied patients. However, in multivariate analysis, only nephropathy [OR (95% CI): 4.25 (1.62-11.17), p=0.003] continued to be significant while SCH showed a marginal trend [OR (95% CI): 0.43 (0.17-1.08), p=0.073].

CONCLUSIONS

The present study suggests an association between SCH and increased UA levels in diabetic patients.

Associations of FSHR and LHCGR gene variants with ovarian reserve and clinical pregnancy rates

RESEARCH QUESTION

Are there any associations between the variants of FSHR c.2039 G>A (p. Ser680Asn, rs6166) and LHCGR c.935A>G (p. Asn312Ser, rs2293275) and ovarian reserve, ovarian response, clinical pregnancy rate and POSEIDON group?

DESIGN

A total of 210 infertile women were enrolled in this prospective study. The gene variants were analysed by the Sanger method. The clinical parameters were analysed based on genotypes.

RESULTS

The frequency of heterozygous and homozygous G allele for FSHR c.2039 G>A in the low prognosis group was significantly higher than that in other response groups (P = 0.034); there was no significant association between LHCGR c.935 A>G and ovarian response. Moreover, the serum anti-Müllerian hormone (AMH) concentration, antral follicle count (AFC), oocytes retrieved, metaphase II (MII) oocytes and two-pronuclear (2PN) oocytes in patients with AG genotype for FSHR c.2039 G>A were significantly lower than those with AA genotype. The serum LH concentrations and clinical pregnancy rate of fresh embryo transfer in patients with GG genotype for LHCGR c.935 A>G were significantly higher than that of the AG genotype. In POSEIDON analysis, the low prognosis women with AA genotype for FSHR c.2039 G>A were more likely to appear in subgroup 1 (P = 0.038).

CONCLUSION

The FSHR c.2039 G>A variant has a significant beneficial influence on ovarian reserve and ovarian response. The LHCGR c.935 A>G variant is associated with increased clinical pregnancy rate of fresh embryo transfer in infertile women. In addition, the low prognosis women with AA genotype for FSHR c.2039 G>A tend to show better ovarian reserve and prognosis.

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.