Hyperferritinemia and hyperuricemia may be associated with liver function abnormality in obese adolescents

Study on risk factor analysis and model prediction of hyperuricemia in different populations

Objectives

The purpose of the present study was to explore the influencing factors of hyperuricemia (HUA) in different populations in Shandong Province based on clinical biochemical indicators. A prediction model for HUA was constructed to aid in the early prevention and screening of HUA.

Methods

In total, 705 cases were collected from five hospitals, and the risk factors were analyzed by Pearson correlation analysis, binary logistic regression, and receiver operating characteristic (ROC) curve in the gender and age groups. All data were divided into a training set and test set (7:3). The training set included age, gender, total protein (TP), low-density lipoprotein cholesterol (LDL-C), and 15 other indicators. The random forest (RF) and support vector machine (SVM) methods were used to build the HUA model, and model performances were evaluated through 10-fold cross-validation to select the optimal method. Finally, features were extracted, and the ROC curve of the test set was generated.

Results

TP, LDL-C, and glucose (GLU) were risk factors for HUA, and the area under the curve (AUC) value of the SVM validation set was 0.875.

Conclusion

The SVM model based on clinical biochemical indicators has good predictive ability for HUA, thus providing a reference for the diagnosis of HUA and the development of an HUA prediction model.

Association between 25 hydroxyvitamin D and serum uric acid level in the Chinese general population: a cross-sectional study

BACKGROUD

The relationship between serum uric acid (SUA) and 25-hydroxyvitamin D (25(OH)D) has been variably characterized in existing literature, with inconsistent results regarding its nature and implications in the Chinese population. This study aims to clarify this association, considering the potential impact of vitamin D levels on SUA.

METHODS

This cross-sectional study involved 7,086 individuals from the Second Affiliated Hospital of Zhejiang University School of Medicine, screened throughout 2020. We collected data on 25(OH)D, SUA, and other metabolic markers. Logistic regression models adjusted for confounding factors were utilized to analyze the relationships.

RESULTS

Our findings illustrate a statistically significant inverted U-shaped relationship between 25(OH)D and SUA. The identified threshold effect at 28.82 ng/ml is pivotal; with 25(OH)D levels below this point associated with an increased risk of hyperuricemia (odds ratio: 1.0146, p = 0.0148), and levels above it offering protective benefits (odds ratio: 0.9616, p = 0.0164).

CONCLUSIONS

Our findings confirm a nonlinear, inverted U-shaped correlation between 25(OH)D and SUA, emphasizing the importance of maintaining vitamin D levels within a specific range to effectively manage hyperuricemia. These results support the implementation of personalized vitamin D supplementation strategies to optimize metabolic health outcomes, highlighting the complex interplay between vitamin D status and uric acid levels.

Prevalence and association of hyperuricemia with liver function in Saudi Arabia: a large cross-sectional study

BACKGROUND

Hyperuricemia is linked to an increased risk of various chronic diseases, but data on the prevalence and association of hyperuricemia with liver function in Saudi Arabia are scarce.

OBJECTIVES

Evaluate the prevalence, association, and risk measures of hyperuricemia and liver function in the Saudi population.

DESIGN

Retrospective, cross-sectional analysis.

SETTING

Database on large portion of Saudi population.

PATIENTS AND METHODS

Laboratory data, age, and gender of the studied subjects were collected from Al Borg Diagnostics. Subjects were stratified, based on their uric acid (UA) levels, into three groups: hypouricemic, normouricemic, and hyperuricemic. The association of UA with liver enzymes was examined in all three groups.

MAIN OUTCOME MEASURES

Association of serum UA levels with alanine transaminase (ALT), aspartate transferase (AST), alkaline phosphatase (ALP), and total bilirubin (TB).

SAMPLE SIZE

13 314 subjects.

RESULTS

Our study showed that the prevalence of hyperuricemia in the Saudi population is 17.3% (20.3% in males and 15.1% in females). We also found a positive correlation between ALT, AST, and TB with UA levels. The risk of being hyperuricemic was significantly increased in individuals with elevated ALT, AST, and TB. Individuals with elevated ALT, AST, and total TB had a higher chance of having hyperuricemia than those with normal activity. Notably, ALT, AST, and TB had good discriminating capacity for hyperuricemia.

CONCLUSIONS

Hyperuricemia is highly prevalent in the Saudi population and is associated with compromised liver function. However, further studies are needed to elucidate the mechanisms underlying these findings in large prospective cohort studies in different populations.

LIMITATIONS

Lack of data on other potential confounding variables.

Associations of Serum Uric Acid Level With Liver Enzymes, Nonalcoholic Fatty Liver Disease, and Liver Fibrosis in Korean Men and Women: A Cross-Sectional Study Using Nationally Representative Data

BACKGROUND

This study aimed to determine whether serum uric acid (SUA) levels are associated with various indices of liver damage in the adult Korean population.

METHODS

We used the Seventh (VII) Korean National Health and Nutritional Examination Surveys. Our study population comprised 6,007 men and 8,488 women. Levels of SUA were divided into four groups (≤ 5.3, 5.3-6.0, 6.0-7.0, and > 7.0 mg/dL for men and ≤ 4.0, 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL for women). Elevated liver enzyme levels were defined as > 35 (men) and > 31 (women) IU/L for aspartate aminotransferase (AST), > 45 (men) and > 34 (women) IU/L for alanine aminotransferase (ALT). Hepatic steatosis index and fibrosis (FIB)-4 index was used to determine nonalcoholic fatty liver disease (NAFLD) and liver FIB, respectively. Adjusted odds ratios (aORs) were calculated by logistic regression analysis for liver enzymes, NAFLD, and liver FIB, according to the SUA level.

RESULTS

Among women, the 4.8-6.0 and > 6.0 mg/dL SUA groups showed higher ORs of elevated AST (aOR, 1.78 and 2.03; 95% confidence interval [CI], 1.37-2.32 and 1.40-2.96, respectively; P < 0.001) and the 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL SUA groups showed a higher ORs of ALT elevation (aOR, 1.35, 2.26, and 2.37; 95% CI, 1.02-1.79, 1.72-2.97, and 1.60-3.50, respectively; P < 0.001) compared to the lowest level SUA group. Among women with normal ALT, > 6.0 mg/dL SUA group showed higher OR of NAFLD status (aOR, 1.52; 95% CI, 1.06-2.19). Among men and women with NAFLD, hyperuricemia showed higher ORs of liver FIB (aOR, 2.25 and 1.89; 95% CI, 1.21-4.19 and 1.09-3.27, respectively) than the lowest level SUA group.

CONCLUSION

High SUA levels may be associated with elevated liver enzymes and NAFLD, mainly in women. Even in women with normal ALT levels, SUA levels may predict the NAFLD status. Hyperuricemia may predict advanced liver FIB in both men and women with NAFLD. Further studies investigating the causal effects of SUA on liver damage are required.

Assessment of the relationship between serum uric acid levels and liver enzymes activity in Bangladeshi adults

Serum uric acid (SUA) level has been suggested to be associated with cardiovascular disease, diabetes and metabolic syndrome. However, little is known about the relationship between SUA and liver enzymes activity in the general population. The present study aimed to assess the relationship between SUA and serum liver enzymes in an adult population in Bangladesh. In this cross-sectional study, a total of 410 blood samples were collected from apparently healthy adults aged > 18 years. SUA, liver enzymes, lipid profile and other biochemical markers were measured in the collected samples by using standard methods. Multinomial logistic regression model was used to assess the relationship between SUA and elevated levels of liver enzymes among the participants. Overall, the prevalence of hyperuricemia was 30.1% with 32.2% in male and 18.6% in female participants. About 33% of the participants had at least one or more elevated levels of liver enzymes. The mean level of SUA was significantly higher in males (389.3 ± 96.9 µmol/L) than in the female (290.4 ± 89.8 µmol/L) subjects (p < 0.001). There was a significant difference in the mean levels of serum ALT and GGT between the male (34.5 ± 16.0 U/L and 26.7 ± 19.5 U/L, respectively) and female (25.0 ± 13.0 U/L and 19.5 ± 13.2 U/L, respectively) participants (p < 0.001 and p < 0.01, respectively). An increasing trend was observed in the mean levels of serum ALT and GGT across the SUA quartile groups (p < 0.001 and p < 0.01, respectively). SUA showed a positive and significant correlation with serum ALT (p < 0.001) and GGT (p < 0.01). In further statistical analysis after adjustment for potential confounders, SUA showed an independent and significant association with serum ALT and GGT in all regression models. In conclusion, SUA was strongly associated with serum levels of ALT and GGT after adjustment for potential confounders. More prospective studies are needed to clarify the complex relationship between SUA and liver enzymes in the general population.

Hereditary hemochromatosis disrupts uric acid homeostasis and causes hyperuricemia via altered expression/activity of xanthine oxidase and ABCG2

Hereditary hemochromatosis (HH) is mostly caused by mutations in the iron-regulatory gene HFE. The disease is associated with iron overload, resulting in liver cirrhosis/cancer, cardiomegaly, kidney dysfunction, diabetes, and arthritis. Fe2+-induced oxidative damage is suspected in the etiology of these symptoms. Here we examined, using Hfe-/- mice, whether disruption of uric acid (UA) homeostasis plays any role in HH-associated arthritis. We detected elevated levels of UA in serum and intestine in Hfe-/- mice compared with controls. Though the expression of xanthine oxidase, which generates UA, was not different in liver and intestine between wild type and Hfe-/- mice, the enzymatic activity was higher in Hfe-/- mice. We then examined various transporters involved in UA absorption/excretion. Glut9 expression did not change; however, there was an increase in Mrp4 and a decrease in Abcg2 in Hfe-/- mice. As ABCG2 mediates intestinal excretion of UA and mutations in ABCG2 cause hyperuricemia, we examined the potential connection between iron and ABCG2. We found p53-responsive elements in hABCG2 promoter and confirmed with chromatin immunoprecipitation that p53 binds to this promoter. p53 protein was reduced in Hfe-/- mouse intestine. p53 is a heme-binding protein and p53-heme complex is subjected to proteasomal degradation. We conclude that iron/heme overload in HH increases xanthine oxidase activity and also promotes p53 degradation resulting in decreased ABCG2 expression. As a result, systemic UA production is increased and intestinal excretion of UA via ABCG2 is decreased, causing serum and tissue accumulation of UA, a potential factor in the etiology of HH-associated arthritis.

Alteration in plasma free amino acid levels and its association with gout

Background

Studies on the association of plasma-free amino acids with gout are very limited and produced conflicting results. Therefore, we sought to explore and characterize the plasma-free amino acid (PFAA) profile in patients with gout and evaluate its association with the latter.

Methods

Data from a total of 819 subjects (including 34 patients with gout) undergoing an annual health examination program in Shimane, Japan were considered for this study. Venous blood samples were collected from the subjects and concentrations of 19 plasma amino acids were determined by high-performance liquid chromatography–electrospray ionization–mass spectrometry. Student’s t-test was applied for comparison of variables between patient and control groups. The relationships between the presence or absence of gout and individual amino acids were investigated by logistic regression analysis controlling for the effects of potential demographic confounders.

Results

Among 19 amino acids, the levels of 10 amino acids (alanine, glycine, isoleucine, leucine, methionine, phenylalanine, proline, serine, tryptophan, valine) differed significantly (P < .001 to .05) between the patient and control groups. Univariate logistic regression analysis revealed that plasma levels of alanine, isoleucine, leucine, phenylalanine, tryptophan and valine had significant positive associations (P < .005 to .05) whereas glycine and serine had significant inverse association (P < .05) with gout.

Conclusions

The observed significant changes in PFAA profiles may have important implications for improving our understanding of pathophysiology, diagnosis and prevention of gout. The findings of this study need further confirmation in future large-scale studies involving a larger number of patients with gout.

Hospitalization and mortality due to hepatitis A in Taiwan: a 15-year nationwide cohort study

Hepatitis A virus (HAV) is the most common food-borne hepatitis in the world. The study objectives were (i) to describe the epidemiology of HAV-related hospitalizations during 1997-2011 in Taiwan, (ii) to examine the age effect on the length of stay (LOS) in hospital and (iii) to study the factors associated with death. The hospitalized cases were identified from the Taiwan National Health Insurance Research Database between 1997 and 2011 by ICD-9-CM code of 070.0/070.1. Patient sex, birthday, dates of hospitalization and death were analysed. A total of 3990 HAV-hospitalized cases, males 2467 (62%), were identified. The LOS increased as patients' age increased. The overall mortality rate was 16.8 per 1000 hospitalizations. Males had significantly higher case fatality rate than females (20.7 vs 10.5 per 1000 cases). The adjusted odds ratio (aOR) for death rose by age and increased rapidly over 40 years of age. The aOR and 95% confidence interval [95%CI] for aged 40-59 years and aged over 60 years were 7.89 (1.06-58.98) and 14.88 (2.02-109.40) compared to aged 0-19 years, respectively. Patients with chronic liver disease and cirrhosis had significantly higher risk of death (aOR=1.03 [1.01-1.04]), compared to those without liver disease. However, patients with liver disease, but no cirrhosis did not have higher risk of death (aOR=1.00 [0.99-1.01]). The aOR [95%CI] for LOS >9 day was 3.26 (1.96-5.40) compared to cases with LOS ≤9 days. Male sex, age over 40 years, cirrhotic liver and long LOS are significant factors associated with death in HAV-hospitalized cases.

Hyperferritinemia increases the risk of hyperuricemia in HFE-hereditary hemochromatosis

OBJECTIVES

Hyperuricemia is becoming increasingly frequent in the population, and is known to be sometimes the cause of gout. The impact of uric acid is still not clearly understood, however. The iron metabolism may interact with the uric acid metabolism. The aim of this study was to examine the relationship between the serum uric acid and serum ferritin levels in a cohort of hemochromatosis patients who were homozygous for the HFE p.Cys282Tyr mutation.

METHODS

738 patients with the HFE gene mutation Cys282Tyr in the homozygous state were included in the study. The variables measured during the initial evaluation were compared in univariate analysis by Student's t test. In multivariate analysis, linear stepwise regression was used.

RESULTS

In the group of hyperuricemic patients, ferritinemia was significantly higher than in the group of non-hyperuricemic patients (1576.7±1387.4μg/l vs. 1095.63±1319.24μg/l, P<0.005). With multivariate analysis, only ferritin and BMI independently explained the uricemia (R²=0.258) after adjustment for age, glycemia and CRP. The correlation between uricemia and log(ferritin) with partial regression correlation coefficients was 0.307 (P<0.01).

CONCLUSIONS

The increase in uricemia is associated with the increase in ferritin in a population of patients who were homozygous for the HFE gene mutation p.Cys282Tyr and this independently of factors commonly associated with hyperuricemia. The increase in uric acid associated with hyperferritinemia, could be a response to the visceral toxicity of excess non-transferrin bound iron linked to oxidative stress via the antioxidant properties of uric acid.

Association between Serum Uric Acid and Elevated Alanine Aminotransferase in the General Population

Background: Both the serum uric acid (SUA) level and elevated alanine aminotransferase (ALT) are related to metabolic syndrome. However, the association between SUA and elevated ALT has not been elucidated in the general population. The objective of this study was to investigate the association between SUA and elevated ALT in the general population of China; Methods: A total of 11,572 adults (≥35 years of age) participated in this survey. Elevated ALT was defined as >40 U/L. SUA ≥ 7.0 mg/dL in males or ≥6.0 mg/dL in females was defined as hyperuricemia. SUA within the reference range was divided into quartiles, and its associations with elevated ALT were evaluated by logistic regressions; Results: A total of 7.4% participants had elevated ALT. The prevalence of hyperuricemia was 14.9% in males and 7.3% in females. There was a significantly positive dose-response association between SUA levels and the prevalence of elevated ALT. After adjusting for potential confounders, a positive relationship for elevated ALT was observed in subjects with hyperuricemia (odds ratio [OR]: 2.032, 95% confidence interval [CI]: 1.443–2.861 for men; OR: 2.045, 95% CI: 1.221–3.425 for women, both p < 0.05). Within the reference range, the association between SUA and elevated ALT persisted in the fourth quartile (OR: 1.467, 95% CI: 1.063–2.025 for men; OR: 1.721, 95% CI: 1.146–2.585 for women, both p < 0.05); Conclusions: Our results indicated that an increased SUA level, even within the reference range, was independently associated with elevated ALT in Chinese adults.

Role of Serum Uric Acid and Ferritin in the Development and Progression of NAFLD

Nonalcoholic fatty liver disease (NAFLD), tightly linked to the metabolic syndrome (MS), has emerged as a leading cause of chronic liver disease worldwide. Since it is potentially progressive towards non-alcoholic steatohepatitis (NASH) and hepatic fibrosis, up to cirrhosis and its associated complications, the need for predictive factors of NAFLD and of its advanced forms is mandatory. Despite the current "gold standard" for the assessment of liver damage in NAFLD being liver biopsy, in recent years, several non-invasive tools have been designed as alternatives to histology, of which fibroscan seems the most promising. Among the different serum markers considered, serum uric acid (SUA) and ferritin have emerged as possible predictors of severity of liver damage in NAFLD. In fact, as widely described in this review, they share common pathogenetic pathways and are both associated with hepatic steatosis and MS, thus suggesting a likely synergistic action. Nevertheless, the power of these serum markers seems to be too low if considered alone, suggesting that they should be included in a wider perspective together with other metabolic and biochemical parameters in order to predict liver damage.