Metabolic syndrome, diabetes, and hyperuricemia. Curr Opin Rheumatol. 2013;25:210-216. [PMID: 23370374 DOI: 10.1097/bor.0b013e32835d951e]

Associations of hyperuricemia and obesity with remission of nonalcoholic fatty liver disease among Chinese men: A retrospective cohort study

Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease that is associated with high serum uric acid (SUA) levels, although the effects of high SUA levels on NAFLD remission remain unclear. In addition, it is unclear whether obesity and high SUA levels have a combined effect on NAFLD remission. This retrospective cohort study evaluated male employees of seven Chinese companies and investigated the association between high SUA levels and NAFLD remission, as well as the potential combined effect of high SUA levels and obesity on NAFLD remission. The study followed 826 men with NAFLD for 4 years, and the NAFLD remission rate was 23.2% (192/826). Comparing to obese and non-obese individuals with normouricemia, individuals with hyperuricemia had significant higher values for total cholesterol, triglycerides, creatinine, and aspartate transaminase (all P < 0.05). Among non-obese individuals, hyperuricemia was associated with a lower NAFLD remission rate, compared to normouricemia (P < 0.001). However, no significant difference was observed between hyperuricemia and normouricemia among obese subjects (P > 0.05). Similar results were observed in the multivariate cox proportional hazard regression analyses. Compared to the normouricemia subjects, individuals with hyperuricemia had a significant lower likelihood of NAFLD remission (RR = 0.535, 95% CI: 0.312-0.916); and obese subjects had a significant lower likelihood of NAFLD remission than the non-obese individuals (RR = 0.635, 95% CI: 0.439-0.918). In addition, the interaction between hyperuricemia and obesity had a statistically significant effect on NAFLD remission (P = 0.048). In conclusion, hyperuricemia and obesity may be involved in NAFLD development and remission, with similar pathogenic mechanisms. Further studies are needed to confirm our findings and determine how to improve these individuals' conditions.

Clinical study on the prevalence and comparative analysis of metabolic syndrome and its components among Chinese breast cancer women and control population

Metabolic syndrome has been previously identified as a risk factor for breast cancer and is increasingly a public health concern. This study aims to investigate the prevalence of metabolic syndrome and its components among primary breast cancer and control population. The clinical data of metabolic syndrome and its components in the breast cancer (605 cases) and control population (3212 cases), from Breast Cancer Center and Physical Examination Center of Chongqing, China, from July 2015 to February 2017, were collected for comparative analysis. This study was prospectively registered in Chinese Clinical Trial Registry (http://www.chictr.org.cn/, number: ChiCTR-OOB-15007543). The prevalence of metabolic syndrome in breast cancer (32.6%) was obviously higher than that in control population (18.2%) (p<0.001; OR: 2.173, 95%CI: 1.793 to 2.633). With age stratification, the prevalence of metabolic syndrome in breast cancer group aged below 60 years (24.9%, p<0.001; OR: 2.216, 95%CI: 1.744 to 2.816) and equal/above 60 years (58.3%, p<0.001; OR: 2.291, 95%CI: 1.580 to 3.322) were also statistically higher than those (13.0% & 37.9%) in control population, respectively. Breast cancer women were more likely to have preobese (BMI 25.0-29.9) or obesity (BMI ≥30.0), broader waist circumference, lower HDL-C level, higher systolic and/or diastolic blood pressure and higher fasting blood glucose level compared to the control population, corresponding prevalence were 31.7%vs.19.4%, 76.0%vs.29.6%, 37.4%vs.30.4%, 34.2%/27.3%vs.27.6%/14.2% and 25.0%vs.20.1%, respectively (p<0.01). In summary, there is high prevalence of metabolic syndrome and its components in Chinese breast cancer women, and metabolic syndrome is closely related with breast cancer. Therefore, screening and prevention strategy of metabolic syndrome should be carried out in the management of breast cancer.

Association of plasma free amino acids with hyperuricemia in relation to diabetes mellitus, dyslipidemia, hypertension and metabolic syndrome

Previous studies demonstrated independent contributions of plasma free amino acids (PFAAs) and high uric acid (UA) concentrations to increased risks of lifestyle-related diseases (LSRDs), but the important associations between these factors and LSRDs remain unknown. We quantified PFAAs and UA amongst Japanese subjects without LSRDs (no-LSRD, n = 2805), and with diabetes mellitus (DM, n = 415), dyslipidemia (n = 3207), hypertension (n = 2736) and metabolic syndrome (MetS, n = 717). The concentrations of most amino acids differed significantly between the subjects with and without hyperuricemia (HU) and also between the no-LSRD and LSRD groups (p < 0.05 to 0.001). After adjustment, the logistic regression analyses revealed that lysine in DM, alanine, proline and tyrosine in dyslipidemia, histidine, lysine and ornithine in hypertension, and lysine and tyrosine in MetS demonstrated significant positive associations with HU among the patients with LSRDs only (p < 0.05 to 0.005). By contrast, arginine, asparagine and threonine showed significant inverse associations with HU in the no-LSRD group only (p < 0.05 to 0.01). For the first time, we provide evidence for distinct patterns of association between PFAAs and HU in LSRDs, and postulate the possibility of interplay between PFAAs and UA in their pathophysiology.

Efficacy of Fenugreek-based bionanocomposite on renal dysfunction and endogenous intoxication in high-calorie diet-induced obesity rat model-comparative study

BACKGROUND

Worldwide obesity spread is a global health problem and needs to be further studied. Co-morbidities of obesity include insulin resistance, diabetes mellitus type 2, and dyslipidemia, which are the most frequent contributing factors for metabolic syndrome (MetS), as well as non-alcoholic fatty liver disease and chronic kidney disease. The aim was to study renal function and endogenous intoxication panel on high-calorie diet-induced obesity rat model and perform comparative study of the treatment efficacy of Fenugreek-based bionanocomposite vs antiobesogenic drugs (Orlistat).

MATERIALS

We included 60 male rats and equally divided them to 6 groups of 10 animals in each group: the experimental groups were firstly assigned as controls and high caloric diet (HCD)-fed groups, and each group further was subdivided to remain untreated, Fenugreek bionanocomposite (BNC)-treated, and Orlistat-treated. Normal control rats (groups 1, 2, 3) were fed by a standard chow, while the others (groups 4, 5, 6) were fed with HCD ad libitum during 98 days. From days 77 to 98, groups 2 and 5 were treated with BNC based on Fenugreek (150 mg/kg body weight, orally) and groups 3 and 6 were treated with antiobesogenic drug Orlistat (10 mg/kg body weight, orally). Food and water consumptions were measured daily and body weights were measured once a week. On day 99, blood was collected; the creatinine, urea, and uric acid were estimated in serum according to the standard protocols. Levels of low and middle molecules (MMs) were measured; the quantity of oligopeptides was estimated by Bradford method. We performed the liver and kidney ultrasonography in rats.

RESULTS

We revealed an increase in the levels of endogenous intoxication syndrome markers (MM and oligopeptides) in all animals with experimental obesity. Ultrasound data showed injury of the liver and kidneys in obese rats. We observed significant decreasing of MM levels after Orlistat treatment vs controls (p < 0.05). However, this effect was more pronounced in Fenugreek BNC-treated group vs both Orlistat-treated and controls (p < 0.05). Orlistat treatment evoked rising of serum creatinine and oligopeptides in control animals and failed to normalize these markers in experimental group. Fenugreek-based BNC treatment did not evoke signs of kidney failure and changes in the studied indices in control group. We noticed normalization levels of uric acid and urea in the blood under the use of BNC and Orlistat.

CONCLUSION

High-calorie diet-induced obesity evokes endogenous intoxication syndrome and kidney dysfunction in rats. Application of Orlistat- and Fenugreek-based BNC decreases MM content to the normal level. Orlistat induces increasing levels of oligopeptides in both groups, likely due to adverse side effects on renal function and its pro-oxidant activity.

β-Hydroxybutyrate Deactivates Neutrophil NLRP3 Inflammasome to Relieve Gout Flares

Aging and lipotoxicity are two major risk factors for gout that are linked by the activation of the NLRP3 inflammasome. Neutrophil-mediated production of interleukin-1β (IL-1β) drives gouty flares that cause joint destruction, intense pain, and fever. However, metabolites that impact neutrophil inflammasome remain unknown. Here, we identified that ketogenic diet (KD) increases β-hydroxybutyrate (BHB) and alleviates urate crystal-induced gout without impairing immune defense against bacterial infection. BHB inhibited NLRP3 inflammasome in S100A9 fibril-primed and urate crystal-activated macrophages, which serve to recruit inflammatory neutrophils in joints. Consistent with reduced gouty flares in rats fed a ketogenic diet, BHB blocked IL-1β in neutrophils in a NLRP3-dependent manner in mice and humans irrespective of age. Mechanistically, BHB inhibited the NLRP3 inflammasome in neutrophils by reducing priming and assembly steps. Collectively, our studies show that BHB, a known alternate metabolic fuel, is also an anti-inflammatory molecule that may serve as a treatment for gout.

Serum uric acid and non-alcoholic fatty liver disease in non-obesity Chinese adults

BACKGROUND

Previous studies found elevated serum uric acid (SUA) was associated with the development or progression of non-alcoholic fatty liver disease (NAFLD) in general population; in this study we aim to investigate the association of SUA and the severity of NAFLD based on grade of fatty liver on ultrasonography in non-obese subjects.

METHODS

Data were obtained from subjects via routine physical examinations in the Public Health Center of our hospital between 2011 and 2014. The data included completed anthropometry and blood biochemical indicators and the results of abdominal ultrasound. The diagnosis of NAFLD was according to the clinical diagnosis of the Guidelines for the diagnosis and treatment of nonalcoholic fatty liver disease in 2008.

RESULTS

In total, 95,924 subjects were analyzed in this study. The prevalence rate of lean-NAFLD was 8.16%, among which 7.58% had mild steatosis, and 0.58% had moderate and severe steatosis. The prevalence of fatty liver was increased progressively with SUA. Among which the prevalence of mild fatty liver from Q1 to Q4 were 10.33%, 18.39%, 23.11% and 25.93%; the prevalence of moderate and severe fatty liver from Q1 to Q4 were 1.06%, 2.82%, 5.05% and 7.27%. Lean-subjects with hyperuricemia had an OR of 1.718 (95% CI 1.622-1.820) to have NAFLD, after adjusted for other metabolic disorders. The area under curve (AUC) for detecting mild fatty liver based on SUA was 0.70; and the AUC for detecting moderate and severe fatty liver based on SUA was 0.78.

CONCLUSIONS

Our data showed positive associations between elevated SUA levels and lean-NAFLD risk in the inland Chinese adults, independent of other metabolic factors. Our study also suggests that SUA could be considered as a simple and non-invasive method to follow up patients with lean-NAFLD.

Study on the correlation between KCNJ11 gene polymorphism and metabolic syndrome in the elderly

The aim of the study was to examine the correlation between KCNJ11 gene polymorphism and metabolic syndrome in elderly patients. From January 2014 to January 2015, 54 elderly patients with metabolic syndrome were enrolled in this study as the observation group. During the same period, 46 healthy elderly individuals were enrolled in this study as the control group. KCNJ11 gene polymorphism (rs28502) was analyzed using polymerase chain reaction-restriction fragment length polymorphism. The expression levels of mRNA in different genotypes were detected using FQ-PCR. ELISA was used to evaluate the KCNJ11 protein expression in different genotypes. KCNJ11 gene polymorphism and metabolic syndrome was studied by measuring the blood pressure levels in patients with different genotypes. Three genotypes of KCNJ11 gene in rs28502 were CC, CT and TT. The CC, CT and TT genotype frequencies in healthy population were 8.5, 9.2 and 82.2%, respectively, while the genotype frequencies in patients with metabolic syndrome were 42.4, 49.8 and 7.8%, respectively. There were significant differences between groups (P≤0.05). However, the genotype frequencies of C/T in healthy individuals and metabolic syndrome patients were 35.3 and 38.3%, respectively. There were no significant differences between groups (P>0.05). FQ-PCR results showed that the KCNJ11 mRNA expression levels in the control and observation groups had no significant differences (P>0.05). However, the results obtained from ELISA analysis revealed that KCNJ11 protein expression level in the observation group was significantly higher than that in the control group (P<0.05). In conclusion, KCNJ11 gene polymorphism is associated with metabolic syndrome in the elderly. Elderly patients with the CC and TT genotypes are more likely to develop metabolic syndrome.

iRhom2 deficiency relieves TNF-α associated hepatic dyslipidemia in long-term PM2.5-exposed mice

Accumulating researches reported that particulate matter (PM2.5) is a risk factor for developing various diseases, including metabolic syndrome. Recently, inactive rhomboid protein 2 (iRhom2) was considered as a necessary modulator for shedding of tumor necrosis factor-α (TNF-α) in immune cells. TNF-α, a major pro-inflammatory cytokine, was linked to various pathogenesis of diseases, including dyslipidemia. Here, wild type (WT) and iRhom2-knockout (iRhom2^-/-) mice were used to investigate the effects of iRhom2 on PM2.5-induced hepatic dyslipidemia. The hepatic histology, inflammatory response, glucose tolerance, serum parameters and gene expressions were analyzed. We found that long-term inhalation of PM2.5 resulted in hepatic steatosis. And a significant up-regulation of iRhom2 in liver tissues was observed, accompanied with elevated TNF-α, TNF-α converting enzyme (TACE), TNFα receptor (TNFR)2 and various inflammatory cytokines expressions. Additionally, PM2.5 treatment caused TG and TC accumulation in serum and liver, probably attributed to changes of genes modulating lipid metabolism. Intriguingly, hepatic injury and dyslipidemia were attenuated by iRhom2^-/- in mice with PM2.5 challenge. In vitro, iRhom2-knockdwon reduced TNF-α expressions and its associated inflammatory cytokines in Kupffer cells, implying that liver-resident macrophages played an important role in regulating hepatic inflammation and lipid metabolism in cells treated with PM2.5. The findings indicated that long-term PM2.5 exposure caused hepatic steatosis and dyslipidemia through triggering inflammation, which was, at least partly, dependent on iRhom2/TNF-α pathway in liver-resident macrophages.

Evaluation of uric acid levels, thyroid function, and anthropometric parameters in Japanese children with Down syndrome

Down syndrome, caused by trisomy 21, is characterized by congenital abnormalities as well as mental retardation. From the neonatal stage through adolescence, patients with Down syndrome often have several complications. Thus, it is important to attain knowledge of the prevalence of these comorbidities in children with Down syndrome. We, therefore, evaluated the biochemical data, thyroid function, and anthropometric parameters, and analyzed the association among them in Japanese children and early adolescents with Down syndrome. There was no difference in the prevalence of obesity and overweight between boys and girls. The level of uric acid was higher in boys than in girls. Moreover, the prevalence of hyperuricemia was also higher in boys than in girls (approximately 32% and 10%, respectively). The prevalence of subclinical hypothyroidism in children with Down syndrome was approximately 20%, with no significant sex differences. The levels of uric acid and dehydroepiandrosterone-sulfate were positively associated with age, while the levels of thyroid-stimulating hormone and free thyroxine had a negative association with age. Overall, children with Down syndrome, exhibit a higher incidence of hyperuricemia. Therefore, uric acid levels, as well as thyroid function, from childhood to early adulthood should be monitored in this patient cohort.

Factors Associated with Benign Paroxysmal Positional Vertigo: A Chinese Case-Control Study

Background

Benign paroxysmal positional vertigo (BPPV) is one of the most common and most successfully treated vestibular disorders. However, there is a lack of predictive factors for BPPV in clinical practice. We aimed to explore several possible predictive factors for BPPV in the Chinese population.

Material/Methods

We enrolled 240 patients with BPPV from Beijing Chaoyang Hospital between July 2013 and July 2016. Biochemical and hematological markers were obtained along with the history of cardiovascular and cerebrovascular diseases.

Results

Serum uric acid (SUA) [279.0±84.7 vs. 331.0±82.7], hemoglobin A1C (HbA1c) [5.75±1.17 vs. 6.61±1.00], albumin [38.1±3.71 vs. 40.9±4.1], and creatinine [68.4±19.3 vs. 81.5±24.1] were significantly lower in patients with BPPV compared with controls (P<0.05). Multiple logistic regression analysis showed that lower levels of HbA1c and albumin were independently associated with BPPV (P<0.05), with odds ratio (OR) 0.680 (95% CI 0.551–0.839) and 0.338 (95% CI 0.190–0.603), respectively. However, the level of SUA was not independently related with BPPV [OR=0.999 (95% CI 0.991–1.006), P=0.713]. There were no significant differences between the parameters of systolic blood pressure, diastolic blood pressure, blood routine examination, lipid profiles, homocysteine, pre-albumin, and blood urea nitrogen in patients with BPPV vs. controls (P>0.05).

Conclusions

Lower levels of HbA1c and albumin were independently associated with BPPV. Although the level of SUA was lower in BPPV patients, SUA was not an independent risk factor for BPPV.

Knockout of the urate oxidase gene provides a stable mouse model of hyperuricemia associated with metabolic disorders

The urate oxidase (Uox) gene encodes uricase that in the rodent liver degrades uric acid into allantoin, forming an obstacle for establishing stable mouse models of hyperuricemia. The loss of uricase in humans during primate evolution causes their vulnerability to hyperuricemia. Thus, we generated a Uox-knockout mouse model on a pure C57BL/6J background using the transcription activator-like effector nuclease (TALEN) technique. These Uox-knockout mice spontaneously developed hyperuricemia (over 420 μmol/l) with about 40% survival up to 62 weeks. Renal dysfunction (elevated serum creatinine and blood urea nitrogen) and glomerular/tubular lesions were observed in these Uox-knockout mice. Male Uox-knockout mice developed glycol-metabolic disorders associated with compromised insulin secretion and elevated vulnerability to streptozotocin-induced diabetes, whereas female mice developed hypertension accompanied by aberrant lipo-metabolism. Urate-lowering drugs reduced serum uric acid and improved hyperuricemia-induced disorders. Thus, uricase knockout provides a suitable mouse model to investigate hyperuricemia and associated disorders mimicking the human condition, suggesting that hyperuricemia has a causal role in the development of metabolic disorders and hypertension.

Hyperuricemia and clustering of cardiovascular risk factors in the Chinese adult population

Hyperuricemia is common in China and the relevance of hyperuricemia and cardiovascular disease (CVD) risk has been highlighted, but to date there has been rarely nation-wide study in China. Here, we aim to estimate the current prevalence of hyperuricemia and evaluate the associations between hyperuricemia and cardiovascular risk factors (CRFs) clustering in a large sample of China adults including a plurality of ethnic minorities. Generally, a nationally representative sample of 22983 adults aged ≥18 years was recruited from 2007 to 2011. Questionnaire data and information on anthropometric characteristics, and laboratory measurements were collected. We define hyperuricemia as SUA ≥416 mmol/L for men and SUA ≥357 mmol/L for women. We found that the prevalence of hyperuricemia was 13.0% (18.5% in men and 8.0% in women). To our estimation, hyperuricemic subjects had higher prevalence rates of CRFs clustering than non-hyperuricemic subjects. Furthermore, there was a dose-response association between the number of CVD risk factors clustering and hyperuricemia. Our study revealed a high prevalence of hyperuricemia and CVD risk factors clustering among Chinese adults, and hyperuricemia was significantly associated with coexistence of more CVD risk factors. Therefore, guidance and effective lifestyle intervention are required to prevent hyperuricemia and CVD risk factors in China.

Identification of C21orf59 and ATG2A as novel determinants of renal function-related traits in Japanese by exome-wide association studies

We have performed exome-wide association studies to identify genetic variants that influence renal function-related traits or confer susceptibility to chronic kidney disease or hyperuricemia in Japanese. Exome-wide association studies for estimated glomerular filtration rate and the serum concentration of creatinine were performed with 12,565 individuals, that for the serum concentration of uric acid with 9934 individuals, and those for chronic kidney disease or hyperuricemia with 5161 individuals (3270 cases, 1891 controls) or 11,686 individuals (2045 cases, 9641 controls), respectively. The relation of genotypes of single nucleotide polymorphisms to estimated glomerular filtration rate or the serum concentrations of creatinine or uric acid was examined by linear regression analysis, and that of allele frequencies of single nucleotide polymorphisms to chronic kidney disease or hyperuricemia was examined with Fisher's exact test. The exome-wide association studies revealed that 25, seven, and six single nucleotide polymorphisms were significantly (P <1.21 × 10-6) associated with estimated glomerular filtration rate or the serum concentrations of creatinine or uric acid, respectively, and that 49 and 35 polymorphisms were significantly associated with chronic kidney disease or hyperuricemia, respectively. Subsequent multivariable logistic regression analysis with adjustment for covariates revealed that four and three single nucleotide polymorphisms were related (P < 0.05) to chronic kidney disease or hyperuricemia, respectively. Among polymorphisms identified in the present study, rs76974938 [C/T (D67N)] of C21orf59 and rs188780113 [G/A (R478C)] of ATG2A may be novel determinants of estimated glomerular filtration rate and chronic kidney disease or of the serum concentration of uric acid, respectively.

Results of an Observational Cohort Study of Hyperuricemia as a Predictor of Poor Physical Performance in the Elderly

OBJECTIVE

Hyperuricemia is frequent in older people and associated with several medical conditions. The relationship between hyperuricemia and physical performance is limited. We aimed to investigate the association between hyperuricemia and physical performance over a 4.4-year followup in the elderly.

METHODS

A total of 1,904 community-dwelling older participants were followed for a mean of 4.4 years. Hyperuricemia at baseline was defined using serum uric acid concentrations ≥6 and ≥7 mg/dl for women and men, respectively. Objective physical performance tests measured included the Short Physical Performance Battery (SPPB), 4-meter gait speed, chair-stands time, leg extension and flexion, handgrip strength, and the 6-minute walking test.

RESULTS

At baseline, participants with hyperuricemia (n = 98 men, 232 women) scored significantly worse in all the tests investigated. After adjusting for 19 covariates, men with hyperuricemia at baseline had an increased risk of having poor SPPB scores at followup (odds ratio [OR] 1.44 [95% confidence interval (95% CI) 1.21-1.72]; P < 0.0001), poor chair-stands time (OR 1.40 [95% CI 1.18-1.6]; P < 0.0001), poor leg extension (OR 1.47 [95% CI 1.21-1.7]; P < 0.0001), and poor handgrip strength (OR 1.54 [95% CI 1.24-1.90]; P < 0.0001). Among women, hyperuricemia was associated with an increased risk of having poor scores in all the SPPB items and in leg flexion (OR 1.26 [95% CI 1.08-1.49]; P = 0.03).

CONCLUSION

Hyperuricemia seems to be significantly associated with poor physical performance in older people, over a followup of 4.4 years. The relationship appears to be more consistent in men than in women. Further longitudinal research is required to better understand the relationships and potential biologic pathways.

Hyperuricemia is not associated with severity of liver fibrosis in patients with nonalcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUND

Uric acid is a natural antioxidant. Previous studies have suggested a protective role of hyperuricemia against liver fibrosis among patients with nonalcoholic fatty liver disease (NAFLD). However, the results were conflicting.

METHODS

MEDLINE and EMBASE databases were searched through August 2016 for studies that investigated the association between hyperuricemia and fibrosis stage among patients with biopsy-proven NAFLD. Pooled odds ratio and 95% confidence interval were calculated using a random-effects model, generic inverse variance method of DerSimonian and Laird. The between-study heterogeneity of effect size was quantified using the Q statistic and I.

RESULTS

A total of five observational studies with 749 NAFLD patients were identified. Patients with NAFLD who had hyperuricemia were not significantly more likely or less likely to have advanced liver fibrosis (defined as fibrosis stage of ≥3) compared with patients with NAFLD who had normal serum uric with the pooled odds ratio of 0.72 (95% confidence interval: 0.34-1.53). The statistical heterogeneity was low with an I of 22% (Pheterogeneity=0.27).

CONCLUSION

Significant protective role of hyperuricemia against the development of advanced liver fibrosis in patients with NAFLD was not observed in this meta-analysis.

Association between the hyperuricemia and nonalcoholic fatty liver disease risk in a Chinese population: A retrospective cohort study

Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease associated with high levels of serum uric acid (SUA). However, whether this relationship applies in obese subjects has been unclear, and no cohort study has previously been conducted in non-obese subjects. We therefore performed a retrospective cohort study among employees of seven companies in China to investigate whether hyperuricemia was independently associated with NAFLD in obese and non-obese subjects, respectively. A total of 2383 initially NAFLD-free subjects were followed up for four years, and 15.2% (363/2383) developed NAFLD. Hyperuricemia subjects had a higher cumulative incidence than did those with normouricemia (29.0% vs. 12.9%, P<0.001). Cox proportional hazard regression analyses showed that baseline hyperuricemia was significantly associated with risk of developing NAFLD in non-obese subjects. This relationship was significantly independent of baseline age, gender, metabolic syndrome components, and other clinical variables (RR = 1.389, 95%CI: 1.051-2.099). However, this association did not exist in obese subjects (RR = 1.010, 95%CI: 0.649-1.571). The independent effect of hyperuricemia on NAFLD was stronger in females (RR = 2.138, 95%CI: 1.050-4.355) than in males (RR = 1.435, 95%CI: 1.021-2.018). In conclusion, further studies are needed to explore the different mechanisms between obese and non-obese subjects, and the reason hyperuricemia raises NAFLD risk in females more than in males.

Development of Nephrolithiasis in Asymptomatic Hyperuricemia: A Cohort Study

BACKGROUND

Although the association between gout and nephrolithiasis is well known, the relationship between asymptomatic hyperuricemia and the development of nephrolithiasis is largely unknown.

STUDY DESIGN

Cohort study.

SETTING & PARTICIPANTS

239,331 Korean adults who underwent a health checkup examination during January 2002 to December 2014 and were followed up annually or biennially through December 2014.

PREDICTOR

Baseline serum uric acid levels of participants.

OUTCOME

The development of nephrolithiasis during follow-up.

MEASUREMENTS

Nephrolithiasis is determined based on ultrasonographic findings. A parametric Cox model was used to estimate the adjusted HRs of nephrolithiasis according to serum uric acid level.

RESULTS

During 1,184,653.8 person-years of follow-up, 18,777 participants developed nephrolithiasis (incidence rate, 1.6/100 person-years). Elevated uric acid level was significantly associated with increased risk for nephrolithiasis in a dose-response manner (P for trend < 0.001) in men. This dose-response association was not observed in women. In male participants, multivariable-adjusted HRs for incident nephrolithiasis comparing uric acid levels of 6.0 to 6.9, 7.0 to 7.9, 8.0 to 8.9, 9.0 to 9.9, and ≥10.0mg/dL with uric acid levels < 6.0mg/dL were 1.06 (95% CI, 1.02-1.11), 1.11 (95% CI, 1.05-1.16), 1.21 (95% CI, 1.13-1.29), 1.31 (95% CI, 1.17-1.46), and 1.72 (95% CI, 1.44-2.06), respectively. This association was observed in all clinically relevant subgroups and persisted even after adjustment for homeostasis model assessment of insulin resistance and high-sensitivity C-reactive protein level.

LIMITATIONS

Dietary information and computed tomographic diagnosis of nephrolithiasis were unavailable.

CONCLUSIONS

In this large cohort study, increased serum uric acid level was modestly and independently associated with increased risk for the development of nephrolithiasis in a dose-response manner in apparently healthy men.

Relationship of serum uric acid level with non-alcoholic fatty liver disease and its inflammation progression in non-obese adults

AIM

This study aimed to evaluate the relationship between serum uric acid (SUA) level and non-alcoholic fatty liver disease (NAFLD) in non-obese adults.

METHODS

A cross-sectional study was carried out among 4098 adults, including 1936 non-obese and 2162 obese individuals. An additional 93 non-obese adults with biopsy-proven NAFLD were also included.

RESULTS

The overall prevalence of NAFLD was 39.51% in the study group, and 14.88% in non-obese adults. The NAFLD patients had significantly higher SUA levels than controls in both men and women. The non-obese group had a higher NAFLD risk with increased SUA levels than the obese group, with odd ratios (95% confidence interval) of 2.559 (1.870-3.503) and 1.692 (1.371-2.087), respectively. In 93 non-obese adults with biopsy-proven NAFLD, SUA levels were significantly higher in those with non-alcoholic steatohepatitis. The prevalence of non-alcoholic steatohepatitis and lobule inflammation tended to increase to 57.58% and 66.67% as the SUA level increased to the fourth quartile. Subjects with hyperuricemia had significantly higher NAFLD activity scores and more serious lobule inflammation than the normal group.

CONCLUSION

Non-obese adults have higher NAFLD risk with increased SUA levels than obese individuals, and the inflammation progression of NAFLD is associated with increased SUA level in non-obese subjects.

Gout in immigrant groups: a cohort study in Sweden

Our aim was to study the association between country of birth and incidence of gout in different immigrant groups in Sweden. The study population included the whole population of Sweden. Gout was defined as having at least one registered diagnosis in the National Patient Register. The association between incidence of gout and country of birth was assessed by Cox regression, with hazard ratios (HRs) and 95% confidence intervals (95% CI), using Swedish-born individuals as referents. All models were conducted in both men and women, and the full model was adjusted for age, place of residence in Sweden, educational level, marital status, neighbourhood socio-economic status and co-morbidities. The risk of gout varied by country of origin, with highest estimates, compared to Swedish born, in fully adjusted models among men from Iraq (HR 1.82, 95% CI 1.54-2.16), and Russia (HR 1.69, 95% CI 1.26-2.27), and also high among men from Austria, Poland, Africa and Asian countries outside the Middle East; and among women from Africa (HR 2.23, 95% CI 1.50-3.31), Hungary (HR 1.98, 95% CI 1.45-2.71), Iraq (HR 1.76, 95% CI 1.13-2.74) and Austria (HR 1.70, 95% CI 1.07-2.70), and also high among women from Poland. The risk of gout was lower among men from Greece, Spain, Nordic countries (except Finland) and Latin America and among women from Southern Europe, compared to their Swedish counterparts. The increased risk of gout among several immigrant groups is likely explained by a high cardio-metabolic risk factor pattern needing attention.

Association of metabolic syndrome and its components with hyperuricemia in a Mediterranean population

Several studies have found an association between hyperuricemia and metabolic syndrome (MS), although there are discrepancies as to which MS components play a pivotal role in this association. We aimed to investigate the association between serum uric acid (SUA) levels and MS in a Mediterranean population (eastern Spain). We performed a case-control study of 71 patients with MS and 122 healthy controls. MS was defined according to the revised National Cholesterol Education Program Adult Treatment Panel III modified criteria. Hyperuricemia was defined as SUA levels >6.55 mg/dL. We determined biochemical, lipidic and inflammatory parameters along with uric acid. Patients with MS showed a higher risk of hyperuricemia than those without MS (OR: 2.87 95% CI: 1.48- 5.55; p = 0.002). In turn, the unadjusted logistic regression analysis showed that hyperuricemia is associated with a higher risk of presenting all the MS components, except hypertension; i.e., hypertriglyceridemia, low HDL-cholesterol, abdominal obesity and glucose intolerance were predictors for hyperuricemia (OR: 3.15, 95% CI: 1.61- 6.15, p = 0.001; OR: 4.07, 95% CI: 1.77- 9.33, p = 0.001; OR: 2.81, 95% CI: 1.41- 5.58, p = 0.003 and OR: 2.82, 95% CI: 1.46- 5.45, p = 0.002 respectively). The adjusted logistic regression analysis revealed that only low HDL-cholesterol and glucose intolerance were independent predictors for hyperuricemia (OR: 2.71, 95% CI 1.06- 6.97, p = 0.038; OR: 2.14, 95% CI 1.01- 4.56, p = 0.049, respectively). In our geographical area, the patients with MS showed a nearly 3-fold risk of hyperuricemia than those without. Among all the MS components, low-HDL-cholesterol and high glucose independently increased more than twice the risk of hyperuricemia, and are the pivotal components involved in hyperuricemia.

Hyperinsulinemia and Insulin Resistance: Scope of the Problem

No abstract available.

Effects of febuxostat on insulin resistance and expression of high-sensitivity C-reactive protein in patients with primary gout

We aimed to investigate the effects of febuxostat on IR and the expression of high-sensitivity C-reactive protein (hs-CRP) in patients with primary gout. Forty-two cases of primary gout patients without uric acid-lowering therapy were included in this study. After a physical examination, 20 age- and sex-matched patients were included as normal controls. The levels of fasting insulin (INS), fasting blood glucose (FBG), and hs-CRP were determined. IR was assessed using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). Gout patients had higher levels of UA, INS, HOMA-IR, and hs-CRP than normal controls (P < 0.05). After 4-, 12-, and 24-week febuxostat treatments, UA and hs-CRP concentrations were significantly lower than baseline (P < 0.05). INS and HOM-IR decreased slightly after a 4-week treatment with febuxostat but declined significantly after 12 and 24 weeks of treatment. Importantly, hs-CRP values positively correlated with those of HOMA-IR (r = 0.353, P = 0.018) and INS (r = 0.426, P = 0.034). Our findings confirm that IR exists in gout patients and implicate that febuxostat can effectively control the level of serum UA and increase insulin sensitivity in primary gout patients.

Kefir reduces insulin resistance and inflammatory cytokine expression in an animal model of metabolic syndrome

There is growing evidence that kefir can be a promising tool in decreasing the risk of many diseases, including metabolic syndrome (MetS). The aim of the present study was to evaluate the effect of kefir supplementation in the diet of Spontaneously Hypertensive Rats (SHR) in which MetS was induced with monosodium glutamate (MSG), and to determine its effect on metabolic parameters, inflammatory and oxidation marker expression and glycemic index control. Thirty animals were used in this experiment. For the induction of MetS, twenty two-day-old male SHR received five consecutive intradermal injections of MSG. For the Negative Control, ten newborn male SHR received intradermal injections of saline solution (0.9% saline solution). After weaning, animals received standard diet and water ad libitum until reaching 3 months old, for the development of MetS. They were then divided into three groups (n = 10): negative control (NC, 1 mL saline solution per day), positive control (PC, 1 mL saline solution per day) and the Kefir group (1 mL kefir per day). Feeding was carried out by gavage for 10 weeks and the animals received standard food and water ad libitum. Obesity, insulin resistance, pro- and anti-inflammatory markers, and the histology of pancreatic and adipose tissues were among the main variables evaluated. Compared to the PC group, kefir supplementation reduced plasma triglycerides, liver lipids, liver triglycerides, insulin resistance, fasting glucose, fasting insulin, thoracic circumference, abdominal circumference, products of lipid oxidation, pro-inflammatory cytokine expression (IL-1β) and increased anti-inflammatory cytokine expression (IL-10). The present findings indicate that kefir has the potential to benefit the management of MetS.

Prevalence and factors associated with hyperuricaemia in newly diagnosed and untreated hypertensives in a sub-Saharan African setting

BACKGROUND

Few studies have evaluated the link between hyperuricaemia and cardiovascular disease in sub-Saharan Africa.

AIMS

To assess the prevalence of and factors associated with hyperuricaemia among newly diagnosed treatment-naïve hypertensive patients in sub-Saharan Africa.

METHODS

We performed a community-based cross-sectional study from January to December 2012 in Douala, Cameroon (Central Africa). We enrolled newly diagnosed treatment-naïve hypertensive patients, and excluded those with gout or a history of gout. Serum uric acid concentrations were measured by enzymatic colourimetric methods, and hyperuricaemia was defined as a serum uric acid concentration>70IU/mL. Fasting blood sugar concentrations, serum creatinine concentrations and lipid profiles were also measured. Logistic regression was used to study factors associated with hyperuricaemia.

RESULTS

We included 839 newly diagnosed treatment-naïve hypertensive patients (427 women and 412 men; mean age 51±11 years; mean serum uric acid concentration 60.5±16.5IU/L). The prevalence of hyperuricaemia was 31.8% (95% confidence interval [CI] 28.7-34.9) and did not differ by sex (132 women vs. 135 men; P=0.56). Multivariable logistic regression identified age>55 years (adjusted odds ratio [AOR] 1.65, 95% CI 1.12-2.29), family history of hypertension (AOR 1.65, 95% CI 1.01-2.67), waist circumference>102cm in men or>88cm in women (AOR 1.60, 95% CI 1.12-2.29), low-density lipoprotein cholesterol>1g/L (AOR 1.33, 95% CI 0.97-1.82) and triglycerides>1.5g/L (AOR 1.63, 95% CI 1.01-2.65) as independently associated with hyperuricaemia.

CONCLUSION

Hyperuricaemia is common among newly diagnosed treatment-naïve hypertensive patients in sub-Saharan Africa and is associated with some components of the metabolic syndrome.

Gout and diabetes: a common combination

The aims of this cross-sectional study were to compare metabolic parameters in people with gout and diabetes with gout only and type 2 diabetes mellitus (T2DM) only. Fifty General Practices in NHS Ayrshire and Arran (population 340 377) contributed data. The sample was split into three groups, those with both gout and T2DM, those with gout only and those with T2DM only. The prevalence of gout in Ayrshire and Arran was 2.65%. The prevalence of gout in people with type 1 and 2 diabetes was 1.90% (p=0.30) and 10.12% (p<10(-5)), respectively. Patients with both conditions were significantly more likely to be male (p<10(-5)), older (p<10(-5)), have a higher mean body mass index (p<0.001), higher triglycerides (p<10(-4)), lower mean total, high-density lipoprotein- and low-density lipoprotein cholesterol (p<10(-5)), lower estimated glomerular filtration rate (p<0.001), neuropathy (p=0.02), lower haemoglobin (p<0.001), to be prescribed more medications (p<10(-5)) and less likely to smoke (p<0.01). There was an association between lower haemoglobin A1c and increased prevalence of gout (p<0.001). 42.4% of patients with gout alone and 36.2% of those with both gout and diabetes had a urate measure. This study defines much more clearly the association between gout and T2DM. Of interest, in terms of lifestyle, both better glycaemic control and smoking are associated with a higher prevalence of gout.

Synergistic association of changes in serum uric acid and triglycerides with changes in insulin resistance after walking exercise in community-dwelling older women

INTRODUCTION

Serum uric acid (SUA) and triglyceride (TG) levels are strongly correlated with insulin resistance; however, the association after a walking exercise program in community-dwelling older women has not been investigated.

METHODS

The present study included 100 postmenopausal women (mean ± standard deviation, 68 ± 7 years) from a rural village in Japan. The Nordic walking program of 120 min per week was performed for 12 weeks. Before and after the intervention, SUA, TG, various relevant factors and homeostasis model assessment of insulin resistance (HOMA-IR) were measured.

RESULTS AND CONCLUSIONS

Multivariate linear regression analysis showed that baseline TG and γ-glutamyltransferase (GGT) were significantly associated with baseline HOMA-IR. After the 12-week training program, changes in TG, SUA and GGT were significantly associated with changes in HOMA-IR. In addition to their direct associations, we observed a synergistic association between changes in TG and SUA and changes in HOMA-IR. Participants were divided into three groups (tertiles) according to changes in TG and SUA. The tertiles of changes in SUA correlated significantly with changes in HOMA-IR in participants in the tertile with the greatest decrease in TG (r = 0.525, p = 0.001), but not in the other two tertiles of change in TG (r = 0.049, p = 0.699). There was a significant interaction between SUA and TG for changes in HOMA-IR (β = 0.281, p = 0.005). These results suggest that changes in TG and SUA are synergistic factors associated with changes in insulin resistance after a 12-week walking exercise program in community-dwelling older women.

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.

Prevalence of nonalcoholic fatty liver disease and its metabolic risk factors in women of different ages and body mass index

OBJECTIVE

This study aims to investigate the prevalence of nonalcoholic fatty liver disease (NAFLD), to determine the metabolic risk factors of this disease, and to predict nonalcoholic steatohepatitis (NASH) with liver fibrosis in women of different ages and body mass index (BMI).

METHODS

In 2010-2011, a cross-sectional survey was conducted among 9,360 women at the health checkup center of Zhongnan Hospital (Wuhan, China). The probability of NASH with liver fibrosis was predicted using BAAT (BMI, age, alanine aminotransferase, and triglycerides) score.

RESULTS

The prevalence of NAFLD increased from 5.3% to 18.8% in women younger than 45 years versus women aged 45 to 55 years and rose to 27.8% in women older than 55 years. In obese women, the prevalence of NAFLD was 48.4%. Women older than 45 years and obese women with NAFLD had more unfavorable metabolic risk factors. Multiple regression analyses showed that increased BMI and low aspartate aminotransferase-to-alanine aminotransferase ratio were closely related to NAFLD in women of different ages, whereas increasing BMI, BAAT score, age, high triglycerides, alanine aminotransferase, and low aspartate aminotransferase-to-alanine aminotransferase ratio were all closely related to NAFLD in obese women. The prevalence of NASH with a BAAT index of 3 or higher was 13.2% and 14.9% in women older than 55 years and obese women with NAFLD, respectively.

CONCLUSIONS

Obese and postmenopausal women have a high prevalence of NAFLD and severe metabolic disorders. The prevalence of NASH seems to be considerably higher in obese and postmenopausal women with NAFLD.

Hyperuricaemia in patients with type 2 diabetes in a tertiary healthcare centre in sub-Saharan Africa: prevalence and determinants

Hyperuricaemia in type 2 diabetes mellitus (T2DM) has been less well investigated in sub-Saharan Africans. Our study of 438 patients found that alcohol intake, body mass index ≥25 kg/m², hydrochlorothiazide use, statin use, diabetic retinopathy and glomerular filtration rate <60 mL/min/1.73m² were independently positively associated with hyperuricaemia; whereas smoking reduced this risk. Hyperuricaemia is strongly associated with some modifiable factors, diabetic complications and certain drugs. Our results suggest that further studies should evaluate the potential cost-benefit of screening for hyperuricaemia in type 2 diabetes.

Association of ABCG2 rs2231142-A allele and serum uric acid levels in male and obese individuals in a Han Taiwanese population

BACKGROUND/PURPOSE

Recent studies suggest that hyperuricemia is a potential risk factor for cardiovascular disease (CVD). Hyperuricemia is highly heritable and is associated with sex and body weight. Previous genome-wide association studies have found that the ABCG2 single nucleotide polymorphism (SNP) rs2231142 is an important genetic factor for increased uric acid (UA) levels, and the degree of association between rs2231142 and hyperuricemia is affected by both sex and ethnicity. This investigation aimed to analyze the association between ABCG2 polymorphisms and UA levels, as well as their interactions with sex and obesity in Taiwanese.

METHODS

Two genetic polymorphisms around the ABCG2 gene were genotyped in 459 patients.

RESULTS

After adjusting for clinical covariates, the rs2231142 SNP was found significantly associated with UA levels using a dominant inheritance model. Patients carrying the rs2231142-A allele had a higher frequency of hyperuricemia than those with the rs2231142-CC allele. Subgroup analysis revealed an association of rs2231142 with UA levels in male or obese patients, and there was no association in nonobese female patients.

CONCLUSION

The rs2231142 SNP is associated with serum UA levels and hyperuricemia in Taiwanese patients and it occurs predominantly in male or obese patients. Hyperuricemia might be controlled differently by sex and obesity.

The Power of Serum Uric Acid in Predicting Metabolic Syndrome Diminishes With Age in an Elderly Chinese Population

OBJECTIVES

Although serum uric acid (sUA) is not a criterion for diagnosing metabolic syndrome (MetS), many studies have identified a positive association between sUA and MetS in patients of various ages and ethnicities. This association has not been fully established in the very elderly.

DESIGN

Cross-sectional and longitudinal study.

SETTING AND PARTICIPANTS

A total of 18,906 Chinese elderly aged 65 and older undergoing routine health checkups in Taiwan were enrolled.

MEASUREMENTS

Modified Adult Treatment Panel III criteria were used to define MetS. All participants were further divided into nine groups with gender specification according to age (the young-old, 65 to 74; old-old, 75 to 84; and oldest-old, 85 and over) and sUA concentration tertile (males: sUAG1, <5.7 mg/dL; sUAG2, 5.7-6.7 mg/dL; and sUAG3, > 6.7 mg/dL; females: sUAG1, <4.9 mg/dL; sUAG2, 4.9-5.9 mg/dL; and sUAG3, > 5.9 mg/dL). A cross-sectional study was first performed to determine the correlation between sUA and MetS and its components. A longitudinal study then excluded subjects with MetS at baseline to explore the risk of MetS according to sUA levels in 3 age groups.

RESULTS

In the cross-sectional study, we observed a graded, positive association between sUA and MetS components that diminished after age 75. Subjects with higher sUA levels had higher odds ratios (OR) for the occurrence of MetS in the young-old and old-old groups of both sexes (P<0.001) except sUAG2 males in the old-old group. However, the association diminished with age and only a higher OR was observed in sUAG2 males in the oldest-old group (OR, 3.38; 95% CI, 1.11-10.30; P = 0.032). In the longitudinal study, the Kaplan-Meier plot showed that higher sUA levels were associated with a higher risk of MetS in the young-old group of both genders (P < 0.001 sUAG3 vs. sUAG1 and sUAG2). Cox regression analysis further confirmed these results (young-old group: sUAG3 HR, 1.90; 95% CI, 1.42-2.54; P < 0.001; old-old group males: HR, 2.20; 95% CI, 1.04-4.65; P = 0.039; young-old females: HR, 1.83; 95% CI, 1.38 - 2.43; P < 0.001).

CONCLUSIONS

Higher sUA levels in the young-old group of Chinese elderly were associated with a higher risk of developing MetS. sUA levels are thus regarded as a potential tool for early diagnosis of MetS. However, this association diminished in those over 75 years of age.

Gout and its comorbidities in the total population of Stockholm

OBJECTIVE

Study of prevalence of gout with concomitant diseases.

METHODS

Study population included all living persons in Stockholm County, Sweden, on January 1st 2013 (N=2,124,959). A diagnosis of gout was identified during 2013-2014, with information of diabetes mellitus and insulin resistance, hypertension, chronic heart failure, chronic kidney disease, alcohol abuse, and malignancies. Age-adjusted odds ratios (ORs) with 95% confidence intervals (95% CI) for women and men with gout, using individuals without gout as referents, were calculated.

RESULTS

Age-adjusted odds of co-morbidities among individuals with gout vs. those without gout were: diabetes mellitus and insulin resistance 3.97 (95% CI 3.65-4.31) in women and 1.88 (95% CI 1.78-1.99) in men; hypertension 4.02 (95% CI 3.69-4.37) in women and 3.21 (95% CI 3.06-3.37) in men; chronic heart failure 4.72 (95% CI 4.31-5.19) in women and 2.84 (95% CI 2.66-3.04) in men; chronic kidney disease 2.08 (95% CI 1.50-2.87) in women and 2.39 (95% CI 2.15-2.66) in men; alcohol abuse 8.98 (95% CI 8.15-9.80) in women and 4.38 (95% CI 4.10-4.69) in men; and malignancies 1.32 (95% CI 1.17-1.48) in women and 1.13 (95% CI 1.06-1.21) men.

CONCLUSION

Gout is a warning sign for concomitant diseases, e.g. alcoholism, diabetes, cardiovascular diseases, and cancer. KEY MESSAGES.

High Risk of Depressive Disorders in Patients With Gout: A Nationwide Population-Based Cohort Study

Metabolic abnormalities are common in patients with depressive disorders. However, the relationship between gout and depression is unclear. We explored the causal relationship among gout, antigout medication, and the associated risk of incidental depressive disorders.In this nationwide cohort study, we sampled data from the National Health Insurance Research Database to recruit 34,050 patients with gout as the gout cohort and 68,100 controls (without gout) as the nongout cohort. Our primary endpoint was the diagnosis of depressive disorders during follow-up. The overall study population was followed up until depression diagnosis, withdrawal from the NHI program, or the end of the study. The differences in demographic and clinical characteristics between both cohorts were determined using the Chi-square test for categorical variables and the t-test for continuous variables. Cox proportional hazard regression models were used to examine the effect of gout on the risk of depression, represented using the hazard ratio with the 95% confidence interval.Patients with gout exhibited a higher risk of depressive disorders than controls did. The risk of depressive disorders increased with age and was higher in female patients and those with hypertension, stroke, and coronary artery disease. Nonsteroidal antiinflammatory drug and prednisolone use was associated with a reduced risk of depression. Patients with gout who had received antigout medication exhibited a reduced risk of depressive disorders compared with nongout patients.Our findings support that gout increases the risk of depressive disorders, and that antigout medication use reduces the risk.

Uric Acid Levels Can Predict Metabolic Syndrome and Hypertension in Adolescents: A 10-Year Longitudinal Study

The relationships between uric acid and chronic disease risk factors such as metabolic syndrome, type 2 diabetes mellitus, and hypertension have been studied in adults. However, whether these relationships exist in adolescents is unknown. We randomly selected 8,005 subjects who were between 10 to 15 years old at baseline. Measurements of uric acid were used to predict the future occurrence of metabolic syndrome, hypertension, and type 2 diabetes. In total, 5,748 adolescents were enrolled and followed for a median of 7.2 years. Using cutoff points of uric acid for males and females (7.3 and 6.2 mg/dl, respectively), a high level of uric acid was either the second or third best predictor for hypertension in both genders (hazard ratio: 2.920 for males, 5.222 for females; p<0.05). However, uric acid levels failed to predict type 2 diabetes mellitus, and only predicted metabolic syndrome in males (hazard ratio: 1.658; p<0.05). The same results were found in multivariate adjusted analysis. In conclusion, a high level of uric acid indicated a higher likelihood of developing hypertension in both genders and metabolic syndrome in males after 10 years of follow-up. However, uric acid levels did not affect the occurrence of type 2 diabetes in both genders.

Liver Fat Content Is Associated with Elevated Serum Uric Acid in the Chinese Middle-Aged and Elderly Populations: Shanghai Changfeng Study

Background and Aims

Although many studies have indicated a relationship between nonalcoholic fatty liver disease (NAFLD) and hyperuricemia, a few studies specifically examining the effects of the severity of liver fat content (LFC) on serum uric acid (SUA) and the presence of hyperuricemia because of the limitation of the examination methods for NAFLD. In this study, we investigate the relationship between the NAFLD and SUA levels in the Chinese population using standardized quantitative ultrasound.

Methods

A community-based study was conducted from May 2010 to December 2012. A total of 4,305 people aged 45 years and above without excessive drinking were enrolled. A standard interview and anthropometric and laboratory blood parameters were collected for each person. The standardized ultrasound hepatic/renal ratio and hepatic attenuation rate was used to quantify LFC.

Results

The prevalence of NAFLD and hyperuricemia was 33.1% and 17.1%, respectively. A total of 23.5% of the NAFLD subjects had hyperuricemia, and their SUA was higher than that of non-NAFLD subjects (327.2±76.8 vs 301.9±77.4 μmol/L, P<0.001). The LFC was positively correlated with SUA (r = 0.130, P<0.001) and an independent factor for SUA (standardized β = 0.054, P<0.001). The OR for the presence of hypreuricemia was 1.175 (95% CI 1.048–1.318; P<0.001) with a 1 SD increase in the log LFC. LFC greater than 10% was related to elevated SUA and an increased presence of hyperuricemia.

Conclusions

LFC accumulation was associated with an increase in the prevalence of hyperuricemia and elevated SUA in our community-based population. LFC greater than 10% is related to the risk for hyperuricemia.

Association between low dietary zinc and hyperuricaemia in middle-aged and older males in China: a cross-sectional study

OBJECTIVE

To examine the associations between dietary zinc intake and hyperuricaemia.

DESIGN

Cross-sectional study.

SETTING

This study was conducted in a health examination centre of China.

PARTICIPANTS

A total of 5168 middle-aged and older participants (aged 40 years or above) (2697 men and 2471 women) were included.

OUTCOME MEASURES

Dietary zinc intake was assessed using a validated semiquantitative food frequency questionnaire. Hyperuricaemia was defined as uric acid ≥416 µmol/L for males and ≥360 µmol/L for females.

RESULTS

For males, the prevalence of hyperuricaemia was 22.9%. After adjusting for age, body mass index (BMI) and energy intake, the ORs were 0.68 (95% CI 0.45 to 0.92) in the second quintile, 0.63 (95% CI 0.45 to 0.89) in the third quintile, 0.68 (95% CI 0.46 to 1.00) in the fourth quintile and 0.55 (95% CI 0.35 to 0.87) in the fifth quintile comparing the lowest quintile of Zn intake, respectively (p for trend=0.03). In the multivariable adjusted model, the relative odds of hyperuricaemia were significantly decreased by 0.71 times in the second quintile of zinc intake (OR 0.71, 95% CI 0.52 to 0.98), 0.64 times in the third quintile (OR 0.65, 95% CI 0.44 to 0.94) and 0.55 times in the fifth quintile (OR 0.56, 95% CI 0.32 to 0.97) compared with those in the lowest quintile, and p for trend was 0.064. For females, the prevalence of hyperuricaemia was 10.0%, and unadjusted, minimally adjusted as well as multivariable adjusted ORs all suggested no significant association between dietary zinc intake and hyperuricaemia.

CONCLUSIONS

The findings of this cross-sectional study indicated that dietary zinc intake was inversely associated with hyperuricaemia in middle-aged and older males, but not in females. The association was significant after considering the influence of age, BMI and energy intake, and after that, minimum adjustment remained independent of further confounding factors such as vitamin C intake, alcohol drinking status and nutrient supplementation.

Serum uric acid: a new therapeutic target for nonalcoholic fatty liver disease

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a major, worldwide public health problem. NAFLD is recognized as a major cause of liver-related morbidity and mortality. However, physicians are currently limited by available treatment options. Recently, numerous studies have reported a correlation between serum uric acid (SUA) and NAFLD with numerous clinical and experimental studies demonstrating a significant correlation. This review will focus on the role of SUA in the development of NAFLD and its potential role as a new target for therapeutic intervention.

AREAS COVERED

This review discusses SUA as a significant independent factor in the development of NAFLD. Moreover, we introduce the causal relationship between SUA, metabolic syndrome, and NAFLD. We discuss two major theories of insulin resistance and inflammasomes as potential explanations of the mechanistic link between SUA and NAFLD. In addition, we review current and emerging therapeutic medications to control appropriate SUA levels.

EXPERT OPINION

There is an urgent need to develop novel, safe and effective therapies for the growing NAFLD epidemic. Reduction of SUA may be a promising potential treatment for patients with NAFLD. Clinical studies are required to determine the therapeutic effect of attenuation of hyperuricemia in humans with NAFLD.

Higher blood hematocrit predicts hyperuricemia: a prospective study of 62,897 person-years of follow-up

This prospective study aimed to investigate the relationship between higher hematocrit (Hct) level and hyperuricemia (HU) incidence. A total of 27,540 subjects were included. Baseline Hct was classified into four categories based on the quartile distribution of the study population. A cox proportional hazards regression was used to evaluate the risk of HU incidence across the Hct quartiles after adjusting a number of potential confounding factors. Out of the 62,897 person-years of follow-up, 2745 new cases of HU were developed. In models adjusted for known risk factors of HU, higher Hct was used to predict HU incidence independently in a graded manner (p = 0.02): compared with subjects in the lowest quartile, subjects in the highest quartile of Hct (hazard ratio = 1.20; 95% confidence interval: 1.03-1.41) were n20% more likely to develop HU. Sensitivity analysis indicated that the hazard ratios increased with the extension of the minimum follow-up interval. When the minimum follow-up interval was restricted to 4 years, subjects in the highest quartile of Hct were 70% more likely to develop HU, compared with the lowest quartile. Higher Hct, a routinely measured inexpensive biomarker was independently associated with the incidence of HU even within the normal range.

[The role of uric acid in the insulin resistance in children and adolescents with obesity]

Objective:

To investigate the association between serum uric acid levels and insulin resistance in children and adolescents with obesity.

Methods:

Cross-sectional study with 245 children and adolescents (134 obese and 111 controls), aged 8-18 years. The anthropometric variables (weight, height and waist circumference), blood pressure and biochemical parameters were collected. The clinical characteristics of the groups were analyzed by t-test or chi-square test. To evaluate the association between uric acid levels and insulin resistance the Pearson's test and logistic regression were applied.

Results:

The prevalence of insulin resistance was 26.9%. The anthropometric variables, systolic and diastolic blood pressure and biochemical variables were significantly higher in the obese group (p<0.001), except for the high-density-lipoprotein cholesterol. There was a positive and significant correlation between anthropometric variables and uric acid with HOMA-IR in the obese and in the control groups, which was higher in the obese group and in the total sample. The logistic regression model that included age, gender and obesity, showed an odds ratio of uric acid as a variable associated with insulin resistance of 1.91 (95%CI 1.40-2.62; p<−0.001).

Conclusions:

The increase in serum uric acid showed a positive statistical correlation with insulin resistance and it is associated with and increased risk of insulin resistance in obese children and adolescents.

Metabolic syndrome in primary gout

BACKGROUND AND OBJECTIVES

Primary gout has traditionally been associated with obesity, arterial hypertension, and abnormal lipid and glucose homeostasis, but we do not know the prevalence of these vascular risk factors in patients with primary gout from a Mediterranean country.

PATIENTS AND METHOD

All patients with primary gout and 2 or more acute arthritis episodes documented by a physician were selected for the study. The diagnosis of MS required ≥3 criteria (ATP III). Patients were classified in two groups: decreased (underexcretors) and normal (normoexcretors) uric acid excretion related to serum urate levels.

RESULTS

One hundred and four patients (mean age, 59 years; 100 males) with primary gout were included in the study. MS was diagnosed in 38 subjects (37%). The most frequent triad defining MS was an increased waist circumference, blood pressure, and trygliceride levels. The prevalence of type 2 diabetes mellitus (T2D) was significantly higher in patients with the MS (21/38, 55%) as compared with subjects without the MS (3/66, 5%; p<0.001). Mean serum urate level in patients with and without MS was identical (8.1 mg/dL), but mean 24-hour uric acid excretion was significantly lower in the former than in the latter (444±110 mg/24-hour/1,73 m2 versus 546±221 mg/day/1,73 m2; p=0.009).

CONCLUSIONS

The condition of the MS occurs in about one-third of the patients with primary gout. Increased waist circumference, blood pressure, and triglycerides levels is the most frequent MS triad. Diminished urinary uric acid excretion is more severe in gout patients with the MS.

Serum Uric Acid Levels and Diabetic Peripheral Neuropathy in Type 2 Diabetes: a Systematic Review and Meta-analysis

Previous studies suggested a possible association between serum uric acid levels and peripheral neuropathy in patients with type 2 diabetes, but no definite evidence was available. A systematic review and meta-analysis of relevant studies were performed to comprehensively estimate the association. Pubmed, Web of Science, Embase, and China Biology Medicine (CBM) databases were searched for eligible studies. Study-specific data were combined using random-effect or fixed-effect models of meta-analysis according to between-study heterogeneity. Twelve studies were finally included into the meta-analysis, which involved a total of 1388 type 2 diabetic patients with peripheral neuropathy and 4746 patients without peripheral neuropathy. Meta-analysis showed that there were obvious increased serum uric acid levels in diabetic patients with peripheral neuropathy (weighted mean difference [WMD] = 50.03 μmol/L, 95% confidence interval [95%CI] 22.14-77.93, P = 0.0004). Hyperuricemia was also significantly associated with increased risk of peripheral neuropathy in patients with type 2 diabetes (risk ratio [RR] = 2.83, 95%CI 2.13-3.76, P < 0.00001). Meta-analysis of two studies with adjusted risk estimates showed that hyperuricemia was independently associated with increased risk of peripheral neuropathy in type 2 diabetic patients (RR = 1.95, 95%CI 1.23-3.11, P = 0.005). Type 2 diabetic patients with peripheral neuropathy have obvious increased serum uric acid levels, and hyperuricemia is associated with increased risk of peripheral neuropathy. Further prospective cohort studies are needed to validate the impact of serum uric acid levels on peripheral neuropathy risk.