Dietary factors associated with hyperuricemia in adults

Perceptions and practices of self-management among adult patients with gout at a primary care clinic: A qualitative study

Introduction

Gout is a chronic disease commonly associated with other comorbidities. Patients' perceived quality of life empowers them in managing their health. Self-management is imparted as part of management among patients with chronic disease. This study aimed to explore the perceptions and practices of self-management among patients with gout from different ethnic groups in Malaysia.

Methods

A qualitative study was conducted among Malay, Chinese and Indian patients with gout via semi-structured in-depth interviews at the primary care clinic of University Malaya Medical Centre in either English or Malay language. All participants had a gout duration of more than 6 months and were either taking urate-lowering drugs or not using them at all.

Results

A total of 20 participants were successfully recruited for the study. Among the participants, 18 were men, while two were women. Further, nine were Malays; six, Chinese; and four, Indians. The age ranged from 29 to 81 years, while the gout duration ranged from 1 to 30 years. From the interviews, three themes emerged: experiences with gout, types of self-management of gout and factors influencing self-management of gout.

Conclusion

Diet control is the main self-management practice of patients with gout. Traditional medicine practices include natural methods such as consumption of different types of vegetable juices, pineapple and papaya. Each ethnicity has its own unique beliefs and food cultures. By understanding the self-management practices of patients from diverse ethnic backgrounds, healthcare practitioners can tailor the treatment of gout to individual needs.

National Nutrition Surveys Applying Dietary Records or 24-h Dietary Recalls with Questionnaires: A Scoping Review

Development of an accurate and efficient dietary method is required for national nutrition surveys. Some countries conduct dietary surveys and combine 24-h dietary records or 24-h dietary recalls with dietary questionnaires. This scoping review aimed to summarize studies that used results from national surveys that combined detailed dietary surveys (dietary records or 24-h dietary recall) and dietary questionnaires and identify the purpose of combining the two methods. The PubMed database and manual searches were used for the literature review. We extracted 58 articles from 16 national nutrition surveys from 14 countries. Most studies used 24-h dietary recall for detailed dietary surveys and the food frequency questionnaire (FFQ) or food propensity questionnaire (FPQ) for questionnaire surveys. Among 37 studies from eight countries, the purpose of combining the two dietary survey methods was to estimate energy and nutrient intakes from detailed dietary surveys and habitual food intake from questionnaires. These findings are useful as a reference when introducing new dietary survey methods in future national nutrition surveys.

A content analysis of online videos containing dietary recommendations for gout and their alignment with evidence-based dietary guidelines

OBJECTIVE

To assess the alignment of YouTube® videos providing dietary recommendations for gout with evidence-based guidelines targeted at the United Kingdom (UK) population and to establish their quality.

DESIGN

A content analysis of YouTube® videos providing dietary recommendations for gout was undertaken. Videos were categorised by video source. Each video's dietary recommendations for gout were compared with three evidence-based guidelines for gout, producing a compliance score. Presence of non-guideline advice was assessed. Understandability and actionability were evaluated using the Patient Education Material Assessment Tool for Audio-Visual Materials. Reliability was assessed using an adapted-DISCERN tool and educational quality using the Global Quality Score Five-Point Scale. Differences between video source and continuous variables were assessed using one-way Kruskal-Wallis H tests. For categorical variables, associations were investigated using Fisher-Freeman-Halton tests.

SETTING

Online, May-June 2020.

PARTICIPANTS

One-hundred thirty-one videos.

RESULTS

Alignment of videos with evidence-based guidelines was poor (median compliance score 27 % (interquartile range 17-37 %)). Additionally, 57 % of videos contained non-guideline advice. The health professional source group had the fewest videos containing non-guideline advice, but this was only significantly lower than the naturopath group (31 % v. 81 %, P = 0·009). Almost 70 % of videos were considered poorly actionable and 50 % poorly understandable. Most videos were rated poor for reliability (79 %) and poor to generally poor for educational quality (49 %).

CONCLUSIONS

YouTube® videos providing dietary recommendations for gout frequently fail to conform to evidence-based guidelines, and their educational quality, reliability, understandability and actionability are often poor. More high-quality, comprehensive, evidence-based YouTube® videos are required for UK gout patients.

The Association between Water Consumption and Hyperuricemia and Its Relation with Early Arterial Aging in Middle-Aged Lithuanian Metabolic Patients

BACKGROUND

Hyperuricemia is well-known as an independent risk factor for the development of hypertension, metabolic syndrome, and cardiovascular disease. Water is essential to most bodily functions, and its consumption rates appear to decline with age. The aim was to evaluate the influence of water intake on early vascular aging in metabolic middle-aged patients with hyperuricemia.

MATERIALS AND METHODS

The study included 241 men aged 40-55 years and 420 women aged 50-65 years from the Lithuanian High Cardiovascular Risk (LitHiR) primary prevention program. Anthropometric characteristics, blood pressure, laboratory testing, and the specialized nutrition profile questionnaire were evaluated. Carotid-femoral pulse wave velocity (cfPWV), assessed using applanation tonometry, was evaluated as an early vascular aging parameter in patients with hyperuricemia and with normal serum uric acid (sUA) levels.

RESULTS

72.6% of men and 83.1% of women drink insufficient amounts of water (less than 1.5 L per day). However, our results showed statistically significant relationships only among a group of women. The women in the hyperuricemic group had a higher cfPWV than women with normal sUA levels. In hyperuricemic women, drinking less than 0.5 L per day in combination with other risk factors, such as age, increasing fasting glucose, and systolic blood pressure, was statistically significantly associated with an increased cfPWV (R² = 0.45, Adj. R² = 0.42, p < 0.001).

CONCLUSION

Drinking an insufficient amount of water daily is associated with increased arterial stiffness and has a negative effect on vascular health in metabolic women with hyperuricemia.

Probiotics, bioactive compounds and dietary patterns for the effective management of hyperuricemia: a review

Hyperuricemia is closely linked with an increased risk of developing hypertension, diabetes, renal failure and other metabolic syndromes. Probiotics, bioactive compounds and dietary patterns are safe cost-efficient ways to control hyperuricemia, whereas comprehensive reviews of their anti-hyperuricemic mechanisms are limited. This review summarizes the roles of probiotics, bioactive compounds and dietary patterns in treating hyperuricemia and critically reviews the possible mechanisms by which these interventions exert their activities. The dietary patterns are closely related to the occurrence of hyperuricemia through the indirect action of gut microbiota or the direct effects of host purine metabolism. The Mediterranean and Dietary Approaches to Stop Hypertension diets help reduce serum uric acid concentrations and thus prevent hyperuricemia. Meanwhile, probiotics alleviate hyperuricemia by ways of absorbing purine, restoring gut microbiota dysbiosis and inhibiting xanthine oxidase (XO) activity. Bioactive compounds such as polyphenols, peptides and alkaloids exert various anti-hyperuricemic effects, by regulating urate transporters, blocking the active sites of XO and inhibiting the toll-like receptor 4/nuclear factor kappa B signaling pathway and NOD-, LRR- and pyrin domain-containing protein 3 signaling pathway. This review will assist people with hyperuricemia to adopt a healthy diet and contribute to the application of natural products with anti-hyperuricemic activity.

Soy consumption and serum uric acid levels: A systematic review and meta-analysis

Background

Soy consumption has health benefits, but the relationship between soy and uric acid remains uncertain. This meta-analysis and systematic review evaluated the effects of soy intake on plasma uric acid.

Methods

PubMed, Embase, CNKI, and the Cochrane Library were searched for studies evaluating the effects of soy, soy products, soy protein, and soy isoflavones on uric acid levels. The primary outcome was serum or plasma uric acid concentration. Study quality was evaluated by the Cochrane Collaboration and SYRCLE risk-of-bias tools.

Results

A total of 17 studies were included. Qualitative analysis of three human clinical studies of acute effects revealed that soy consumption increased serum uric acid concentration; however, soy-derived products, including tofu, bean curd cake, and dried bean curd sticks, had no significant effect on serum uric acid. A meta-analysis of five long-term human studies (10 data sets) revealed that soy protein and soy isoflavones had no significant effects on uric acid levels [weighted mean difference (WMD) = -2.11; 95% confidence interval (CI): -8.78, 4.55; p = 0.53]. However, most epidemiological data revealed that soy intake is inversely associated with uric acid levels. Meta-analysis of nine animal trials (29 data sets) revealed that soy protein and soy isoflavones significantly reduced serum uric acid concentrations (vs. controls; MD = -38.02; 95% CI: -50.60, -25.44; p < 0.001).

Conclusion

Soy and its products have different effects on serum uric acid. Soy products like tofu, bean curd cake, and dried bean curd sticks could be high-quality protein sources for individuals with hyperuricemia or gout. It can be beneficial to nutritionists and healthcare decision-makers reconsider their conceptions about the relationship between soy and uric acid levels according to the latest and further scientific study results.

Systematic review registration

[www.crd.york.ac.uk/PROSPERO], identifier [CRD42022331855].

Trends in the Contribution of Genetic Susceptibility Loci to Hyperuricemia and Gout and Associated Novel Mechanisms

Hyperuricemia and gout are complex diseases mediated by genetic, epigenetic, and environmental exposure interactions. The incidence and medical burden of gout, an inflammatory arthritis caused by hyperuricemia, increase every year, significantly increasing the disease burden. Genetic factors play an essential role in the development of hyperuricemia and gout. Currently, the search on disease-associated genetic variants through large-scale genome-wide scans has primarily improved our understanding of this disease. However, most genome-wide association studies (GWASs) still focus on the basic level, whereas the biological mechanisms underlying the association between genetic variants and the disease are still far from well understood. Therefore, we summarized the latest hyperuricemia- and gout-associated genetic loci identified in the Global Biobank Meta-analysis Initiative (GBMI) and elucidated the comprehensive potential molecular mechanisms underlying the effects of these gene variants in hyperuricemia and gout based on genetic perspectives, in terms of mechanisms affecting uric acid excretion and reabsorption, lipid metabolism, glucose metabolism, and nod-like receptor pyrin domain 3 (NLRP3) inflammasome and inflammatory pathways. Finally, we summarized the potential effect of genetic variants on disease prognosis and drug efficacy. In conclusion, we expect that this summary will increase our understanding of the pathogenesis of hyperuricemia and gout, provide a theoretical basis for the innovative development of new clinical treatment options, and enhance the capabilities of precision medicine for hyperuricemia and gout treatment.

Genome-wide meta-analysis revealed several genetic loci associated with serum uric acid levels in Korean population: an analysis of Korea Biobank data

The serum uric acid (SUA) level is an important determinant of gout, hypertension, metabolic syndrome, and cardiovascular disease. Although previous genome-wide studies have identified multiple genetic variants associated with SUA, most genetic analyses have focused on individuals with European ancestry; thus, understanding of the genetic architecture of SUA is currently limited for Asian populations. We conducted a genome-wide meta-analysis based on Korea Biobank data consistent with three cohorts; namely, the Korean Genome and Epidemiology Study (KoGES) Ansan and Ansung, KoGES Health Examinee, and KoGES Cardiovascular Disease Association studies. In total, 60,585 participants aged ≥40 years were included in the analysis of the three cohorts. We used logistic regression analyses to perform genome-wide association study (GWAS) adjustments for confounding variables. Subsequently, a meta-analysis was conducted by combining the analyses of the three GWASs. We identified 8,105 variants at 22 genetic loci with a P value < 5 × 10^-8. Among these, six novel genetic loci associated with SUA in the Korean population were identified (rs4715517 in HCRTR2, rs145099458 in 3.2 kb 3' of MLXIPL, rs1137642 in B4GALT1, rs659107 in LOC105378410, rs7919329 in LOC107984274, and rs2240751 in MFSD12). Our meta-analysis provides insights into the genetic architecture of SUA in the Korean population. Further studies are warranted to replicate the study results and elucidate the specific role of these variants in SUA homeostasis.

Association between Dietary Fiber Intake and Hyperuricemia among Chinese Adults: Analysis of the China Adult Chronic Disease and Nutrition Surveillance (2015)

This study aimed to assess the association of dietary fiber intake with serum uric acid (SUA) levels and risk of hyperuricemia (HUA) among Chinese adults using the latest nationally representative data. A total of 66,427 Chinese adults aged 18 years and over from the China Adult Chronic Disease and Nutrition Surveillance in 2015 were included in this study. Dietary intakes were measured with a 3-day 24 h dietary recall and the household condiment weighing method. Mixed-effect linear and logistic regression models were used to evaluate the associations of dietary fiber intake with SUA levels and risk of HUA, respectively. Compared to the lowest intake group, the coefficient and 95% confidence in the highest intake group of total fiber were −0.06 (−0.08, −0.04) (p-trend < 0.001), −0.18 (−0.2, −0.16) (p-trend < 0.001) for cereal fiber, 0.03 (0.01, 0.04) (p-trend = 0.051) for legume fiber, 0 (−0.01, 0.02) (p-trend = 0.869) for vegetable fiber and 0.01 (−0.001, 0.04) (p-trend = 0.296) for fruit fiber. The odds ratio (OR) and 95% confidence interval (CI) of HUA for the highest vs. lowest intake group of total fiber were 0.88 (0.84, 0.91) (p-trend = 0.001), 0.67 (0.63, 0.71) (p-trend < 0.001) for cereal fiber, 1.05 (1, 1.09) (p-trend = 0.248) for legume fiber, 1.01 (0.97, 1.05) (p-trend = 0.982) for vegetable fiber and 1.06 (1, 1.12) (p-trend = 0.264) for fruit fiber. Our findings suggest that consumption of total fiber and cereal fiber were significantly inversely associated with SUA levels and HUA risk among the Chinese adult population. Developing and implementing effective public education programs are urgently needed to increase the intake of dietary fiber, especially cereal fiber among Chinese adults.

Tea Consumption is Associated with an Increased Risk of Hyperuricemia in an Occupational Population in Guangdong, China

Purpose

Chronic hyperuricemia leads to long-term deposition of monosodium urate crystals that may damage the joint structure and affect quality of life. Although hyperuricemia prevalence varies, most studies indicate increased cases of hyperuricemia worldwide. The relationship between hyperuricemia and tea consumption is uncertain. This cross-sectional study investigated the effect of tea consumption on the risk of hyperuricemia in the working population in Guangdong, China.

Patients and Methods

Data on weight, height, blood pressure, laboratory test results, and health questionnaire responses of 7644 adults aged ≥18 years were obtained from the health examinee dataset of Nanfang Hospital. The characteristics of subjects with and without hyperuricemia were compared using t-tests or non-parametric Mann–Whitney U-tests for continuous variables and chi-square tests for categorical variables. Relationships between hyperuricemia and participant characteristics (sex, age, education level, smoking history, alcohol consumption, hypertension, body mass index, tea consumption, and other dietary factors) were examined using univariate and multivariate logistic regression models to identify independent risk factors for hyperuricemia.

Results

Tea consumption was associated with a higher risk of hyperuricemia in the crude model (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.48–2.05, once a month through twice a week vs never, P<0.001; OR 2.44, 95% CI 2.07–2.89, ≥3 times a week vs never, P<0.001). The adjusted OR for hyperuricemia was 1.30 (95% CI 1.08–1.56, P=0.006) in participants who consumed tea once a month through twice a week and 1.35 (95% CI 1.11–1.64, P=0.003) in those who consumed tea ≥3 times a week compared with the “never” reference group after adjusting for sociodemographic factors, anthropometric and biochemical indices, and dietary factors. This relationship remained significant in men but not women in subgroup analysis.

Conclusion

Tea consumption is an independent risk factor for hyperuricemia and is more pronounced in men than women.

The epigenome: key to understanding and predicting gout flares

Gout is a form of arthritis, resulting from an inflammatory reaction to the deposition of monosodium urate (MSU) crystals in the synovial fluid of the joint space. It is characterised by periods of acute inflammation in the affected joint, or joints (known as gout flares), separated by asymptomatic periods. There seems to be substantial overlap between environmental triggers of gout flares and common environmental modifiers (diet, pharmaceuticals, and stress) of epigenetic markers (DNA methylation, histone modifications, and ncRNA). Very few studies have looked at whether environment is influencing gout through epigenetic mechanisms. The pathogenesis of gouty inflammation is well understood but understanding the variation of response to hyperuricaemia in terms of gout flare initiation is less well known. In this review, we will examine the potential of epigenomics in understanding how gout flares may occur, both in terms of development of hyperuricaemia and the inflammatory response. Looking at the epigenome and its intersection with lifestyle could help identify new targets and strategies for effective management of gout flares.

Impact of Coffee/Green Tea/Soft Drink Consumption on the Risk of Hyperuricemia: A Cross-Sectional Study

This cross-sectional study aimed to investigate the association between hyperuricemia and the frequency of coffee, tea, and soft drink consumption, based on data from the Korean Genome and Epidemiology Study (KoGES) (2004-2016). We used the KoGES health examinee data, obtained from urban residents aged ≥ 40 years. Information on the participants' medical history, nutrition (total calorie, protein, fat, and carbohydrate intake), frequency of alcohol consumption, smoking status, household income, and frequency of coffee/green tea/soft drink intake was collected. A logistic regression model was used to analyze the data. Subgroup analyses were performed according to the participant's age and sex. Among 173,209 participants, there were 11,750 and 156,002 individuals with hyperuricemia and non-hyperuricemia controls, respectively. In an adjusted model, frequent coffee and green tea consumption did not increase the risk of hyperuricemia, compared to the "no intake" reference group. However, an adjusted odds ratio of hyperuricemia was 1.23 (95% confidence interval, 1.11-1.35, p < 0.001) for participants who reported consuming soft drinks ≥ 3 times per day, compared to the respective "no drink" reference group. Even after adjusting for nutritional and sociodemographic factors, frequent soft drink intake was associated with an increased risk of hyperuricemia. Meanwhile, neither coffee nor green tea intake was associated with an increased risk of hyperuricemia.

Sugar-sweetened soft drinks consumption and risk of hyperuricemia: Results of the ELSA-Brasil study

BACKGROUND AND AIMS

The prospective association between sugar-sweetened beverages consumption and hyperuricemia is controversial. The aim was to investigate the association of the consumption of sugar-sweetened soft drinks and unsweetened fruit juices with the incidence of hyperuricemia and the levels of serum uric acid in the participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

METHODS AND RESULTS

Longitudinal analysis in ELSA-Brasil participants (baseline 2008-2010 and follow-up 2012-2014). The sample consisted of 10,072 civil servants (35-74 years, both sexes). The consumption of beverages estimated by a food frequency questionnaire (baseline) was divided into five categories: nonconsumption and quartiles (≥0.1 mL/day). Hyperuricemia was defined as uric acid ≥7.0 mg/dL (men) and ≥5.7 mg/dL (women). Poisson regression with robust variance and multiple linear regression were tested. The average consumption of soft drinks was 84 ± 191 mL/day in men and 42 ± 128 mL/day in women. After 4 years of follow-up, the higher consumption of soft drinks (men: 401 ± 303 mL/day; women: 390 ± 290 mL/day) increased the relative risk of hyperuricemia by 30% (men) and 40% (women), and was associated with increased mean uric acid (men: β = 0.14 mg/dL; 95% CI 0.41-0.24; women: β = 0.11 mg/dL; 95% CI 0.00-0.21). The consumption of unsweetened juice was not associated with hyperuricemia.

CONCLUSION

High consumption of sugar-sweetened soft drinks is associated with an increased relative risk of hyperuricemia and elevated serum uric acid levels in Brazilian adults.

Association between consumption of ultra-processed foods and hyperuricemia: TCLSIH prospective cohort study

BACKGROUND AND AIMS

Emerging evidence suggests that consumption of ultra-processed foods (UPF) plays a role in the development of chronic diseases, but evidence of their influence on hyperuricemia is limited. We therefore designed a cohort study to examine whether UPF consumption increase the risk of hyperuricemia in adults.

METHODS AND RESULTS

This was a prospective study (n = 18,444) performed in Tianjin, China from 2013 to 2019. Participants that were aged 18 years and over and with no history of hyperuricemia, were followed up for 1-6 years (median follow-up duration = 4.2 years). UPF consumption was assessed by a validated semi-quantitative food frequency questionnaire. Hyperuricemia was defined as serum uric acid levels ≥7.0 mg/dL in males and ≥ 6 mg/dL in females. Multivariable Cox proportional hazards regression models were used to assess the association between UPF consumption and the risk of hyperuricemia. Restricted cubic spline regression was used to estimate the dose-response association between UPF consumption and risk of hyperuricemia. During follow-up period, the incidence of hyperuricemia was 20.3% in general population (27.7% in males and 13.2% in females). In the final multivariate models, the hazard ratios (95% confidence interval) for hyperuricemia across energy adjusted UPF consumption quartiles were 1.00 (reference), 1.04 (0.94, 1.14), 1.11 (1.01, 1.23), 1.16 (1.05, 1.28) (p for trend = 0.02) in general population.

CONCLUSIONS

This population-based prospective cohort study suggests that increased consumption of UPF is independently associated the risk of hyperuricemia.

Association Between Dietary Intake and Serum Uric Acid Levels in Kidney Transplant Patients

OBJECTIVES

The aim of this study was to evaluate the association between dietary intake and uric acid (UA) levels in kidney transplant patients (KTPs).

METHODS

A cross-sectional study was performed with 113 KTPs. Dietary intake assessment was carried out thorough two 24-hour dietary recalls using the 5-step multiple pass method. We evaluated the intake of energy, carbohydrate, total protein, animal protein, vegetable protein, total fat, saturated fat, trans fat, monounsaturated fat, polyunsaturated fat, omega-3 and omega-6 fatty acids, cholesterol, total sugar, added sugars, total fiber, insoluble fiber, soluble fiber, alcohol, caffeine, fructose, glucose, lactose, sucrose, vitamin A, vitamin C, vitamin E, and calcium. The intake of several food groups (portions) was also evaluated. Hyperuricemia was classified as >7.0 and >6 mg/dL for men and women, respectively.

RESULTS

In odds ratio analyses, the individuals who ingested more vegetable protein (g/kg) and caffeine (mg) presented lower chance to have hyperuricemia. In linear regression, animal protein (g) intake was positively associated (β = 0.011, P = .048), while vegetable protein (g/kg) intake was inversely associated (β = -2.45, P = .047) with serum UA. However, after a multiple linear regression including vegetable and animal protein intakes together, only vegetable protein intake remained associated with UA. The intake of other nutrients and portions of food groups was not associated with UA. All the analyses were adjusted for sex, age, hypertension, body mass index, glomerular filtration rate, use of medicines, and caloric intake misreporting.

CONCLUSIONS

Vegetable protein and caffeine intakes were inversely associated with UA in KTPs.

The role of alcohol consumption in pathogenesis of gout

Alcohol is recognized a risk factor for increased uric acid and gout flare. The aim of the study was to review the literature in order to find out what is the role of alcohol consumption in pathogenesis of gout. A search in PubMed, Google Scholar, Medline Complete database was performed in January 2021. The databases were searched with the phrases: "uric acid and alcohol," "alcoholic beverages and gout," "hyperuricemia and alcoholic beverages consumption" published between 2000 and 2021. A total of 2642 results were found. The 99 non-duplicate citations were screened. Then 81 articles were excluded after abstract screen. After that 18 articles were retrieved. Eventually 15 articles were included for systematic review. Several authors see the positive correlation between beer or distilled spirits consumption and gout. Some include wine to the list of triggers of gout. Others state that moderate wine consumption protects from gout attacks due to antioxidants and phytoestrogen content. Majority noticed the relationship between episodic alcohol consumption and gout attacks. Episodic alcohol intake triggers gout attacks, regardless of type of alcohol. Thus, individuals with established gout and pre-existing risk factors should limit all types of alcohol intake to prevent gout episodes.

The Association between Purine-Rich Food Intake and Hyperuricemia: A Cross-Sectional Study in Chinese Adult Residents

OBJECTIVE

To explore the correlation between purine-rich food intake and hyperuricemia in Chinese adult residents.

METHOD

A cross-sectional study was conducted on the purine-rich food intake of Chinese adult residents based on the China Health and Nutrition Survey (CHNS) in 2009. The subjects were divided into hyperuricemia group and nonhyperuricemia group according to serum uric acid level, and the differences of the sociodemographic information (age, gender, and region), health status (weight status, blood pressure, blood sugar status), living habits (alcohol consumption, smoking status) and food intake (purine-rich food, other food) were compared between the two groups. Logistic regressions investigated the associations between the daily intake of purine-rich food (animal-derived food and legumes) and hyperuricemia.

RESULTS

Eventually, 6813 subjects were included in our study, 1111 of them had hyperuricemia. The intake of seafood, legumes, red meat, and poultry all increased the risk of hyperuricemia (p < 0.05), while the intake of purine-rich fungi and purine-rich vegetables did not affect the occurrence of hyperuricemia. Animal-derived food was the main source of purine-rich food consumed by Chinese adult residents (140.67g/day), which had a great impact on hyperuricemia. Finally, after adjusting for gender, age, region, body mass index (BMI), alcohol consumption, hypertension, and refined grains intake, the risk of hyperuricemia increased by 2.40% and 1.10% for each increase of 10 g in animal-derived food intake (OR = 1.024, 95% CI: 1.018-1.030) and legumes intake (OR = 1.011, 95% CI: 1.003-1.019), respectively.

CONCLUSION

The intake of animal-derived food and legumes were positively correlated with the occurrence of hyperuricemia. Controlling the intake of animal-derived food and legumes would be more beneficial to controlling the risk of hyperuricemia.

Sugar-containing carbonated beverages consumption is associated with hyperuricemia in general adults: A cross-sectional study

BACKGROUND AND AIMS

Research evidence supports a positive link between sugar-containing soft beverages and hyperuricemia. However, data thus far are mostly from Caucasian populations. And in sugar-containing soft beverages overall, sugar-containing carbonated beverages are purchased most often. Therefore, we investigated whether the high consumption of sugar-containing carbonated beverages was associated with the prevalence of hyperuricemia among adults in China.

METHODS AND RESULTS

A cross-sectional study was conducted with 25,507 adults (13,013 men and 12,494 women) in Tianjin, China. Sugar-containing carbonated beverages intake was assessed by a validated semi-quantitative food frequency questionnaire. Hyperuricemia was defined as serum uric acid levels ≥7.0 mg/dL in men and ≥ 6 mg/dL in women. The association between carbonated beverages consumption and hyperuricemia was assessed by multiple logistic regression analysis. The prevalence of hyperuricemia in men and women was 23.4% and 8.2%, respectively. After adjustments for potential confounding factors, the odds ratios (95% confidence interval) for hyperuricemia across sugar-containing carbonated beverages consumption were 1.00 (reference) for almost never, 1.18 (1.05, 1.32) for <1-3 cups/week, 1.49 (1.25, 1.77) for ≥4 cups/week in men (P for trend < 0.005) and 1.11 (0.91, 1.34) for <1-3 cups/week (P for trend = 0.27), 1.70 (1.23, 2.31) for ≥4 cups/week in women (P for trend < 0.001), respectively.

CONCLUSIONS

This cross-sectional survey demonstrated that increased consumption of sugar-containing carbonated beverages is associated with hyperuricemia among adults in China. Restricted sugar-containing carbonated beverages intake might be beneficial to the prevention of hyperuricemia in the general population.

Hyperuricemia versus lifestyle in men and women of the Russian Federation population

Objective ― Analyzing gender-related specificities of hyperuricemia associations with lifestyle choices in the Russian Federation (RF) population. Material and Methods ― Cross-sectional survey was performed within the guidelines of the Russian national multicenter study ESSE-RF. The final sample size was 20781 people 25-64 years old. The effect of age, body mass index (BMI), diet, smoking status, and alcohol consumption on the incidence of hyperuricemia was evaluated. The analysis was carried out separately for men and women, using logistic regression. To build a model for predicting hyperuricemia, classification trees were used. Results ― Multidirectional associations of hyperuricemia were revealed both in women (with BMI, age, ‘Smart’ dietary pattern, alcohol consumption) and in men (with BMI, ‘smart’ dietary pattern, alcohol consumption, smoking status). The predictive accuracy of hyperuricemia incidence models was 60.4% in women vs. 65.7% in men. In both gender groups, BMI had the highest contribution to predicting the hyperuricemia incidence, while the next predictors, in terms of significance, differed among men and women. In women, the greatest impact, in decreasing order, was exerted by age, dietary patterns and drinking, whereas in men, by smoking status, dietary patterns and drinking. Conclusion ― In the RF population, there are multiple gender-specific associations of hyperuricemia with lifestyle choices, particularly nutrition, smoking and alcohol consumption.

Association between retinol intake and hyperuricaemia in adults

OBJECTIVE

Current evidences on the association between hyperuricaemia and retinol intake remain inconsistent. Furthermore, no known studies have investigated the relationship between hyperuricaemia and retinol intake from animal food and plant food separately. This study aimed to assess the relationship between different sources of retinol intake and risk of hyperuricaemia among US adults.

DESIGN

Univariate and multivariate weighted logistic regression models and restricted cubic spline models were used to assess the associations of total, animal-derived and plant-derived retinol intakes with the risk of hyperuricaemia. Dietary retinol was measured through two 24-h dietary recall interviews. Hyperuricaemia was defined as serum uric acid level ≥7·0 and ≥6·0 mg/dl in men and women, respectively.

SETTING

Data from the National Health and Nutrition Examination Survey 2009-2014 were used in this cross-sectional study.

PARTICIPANTS

Overall, 12 869 participants aged ≥20 years were included.

RESULTS

Compared with the lowest quintile, the multivariable OR of hyperuricaemia for the highest quintile intake of total, animal-derived and plant-derived retinol were 0·71 (95 % CI 0·52, 0·96), 0·76 (95 % CI 0·59, 0·96) and 0·92 (95 % CI 0·72, 1·17), respectively. The inverse association between dietary intake of total retinol and the risk of hyperuricaemia was observed in men. Dose-response analyses revealed a novel linear trend between the risk of hyperuricaemia and total, animal-derived retinol intake separately.

CONCLUSIONS

Our findings indicated that intakes of total and animal-derived retinol were negatively associated with hyperuricaemia in US adults.

Wastewater-based estimation of the prevalence of gout in Australia

Allopurinol, a first-line gout treatment drug in Australia, was assessed as a wastewater-based epidemiology biomarker of gout via quantification of the urinary metabolite, oxypurinol in wastewater. The in-sewer stability of oxypurinol was examined using laboratory-scale sewer reactors. Wastewater from 75 wastewater treatment plants across Australia, covering approximately 52% (12.2 million) of the country's population, was collected on the 2016 census day. Oxypurinol was quantified in the wastewater samples and population-weighted mass loads calculated. Pearson and Spearman rank-order correlations were applied to investigate any link between allopurinol, other selected wastewater biomarkers, and socio-economic indicators. Oxypurinol was shown to be stable in sewer conditions and suitable as a WBE biomarker. Oxypurinol was detected in all wastewater samples. The estimated consumption of allopurinol ranged from 1.9 to 32 g/day/1000 people equating to 4.8 to 80 DDD/day/1000 people. The prevalence of gout across all tested sewer catchments was between 0.5% to 8%, with a median of 2.9% nationally. No significant positive correlation was observed between allopurinol consumption and alcohol consumption, mean age of catchment population, remoteness or higher socioeconomic status. There was a significant positive correlation with selective analgesic drug use. Wastewater analysis can be used to study gout prevalence and can provide additional insights on population level risk factors when triangulated with other biomarkers.

Improvement of hyperuricemia in chronic hepatitis C patients receiving directly acting antiviral agents

BACKGROUND AND AIM

Hepatitis C virus eradication via the use of antivirals ameliorates metabolic profiles. The changes in serum uric acid (SUA) levels in chronic hepatitis C patients who receive antivirals are not well understood. We aimed to address this issue by comparing the SUA changes before and after the achievement of a sustained virological response (which is defined as hepatitis C virus RNA seronegativity at 12 weeks after the end of treatment).

METHODS

Two hundred and thirteen sustained virological response patients who were treated by directly acting antivirals were consecutively enrolled. Pretreatment and post-treatment SUA levels were compared. Hyperuricemia was defined as a uric acid level > 7.0 mg/dL in men and > 6.0 mg/dL in women.

RESULTS

The SUA levels significantly decreased after treatment, as compared to the pretreatment levels (5.6 ± 1.5 vs 6.0 ± 1.7 mg/dL, respectively; P < 0.001). The proportion of hyperuricemia incidences significantly decreased after treatment (25.8% vs 35.7%, respectively; P = 0.001). The improvement was only observed in patients with a fibrosis-4 index (FIB-4) < 6.5 (25.7% vs 37.1%, P = 0.001) but not in those patients with a FIB-4 ≧ 6.5 (26.3% vs 28.9%, P = 1.00). A multivariate analysis revealed that the factor that was associated with significantly decreased SUA levels was FIB-4 < 6.5 (odds ratio [OR]/95% confidence interval [CI]: 3.22/1.04-9.95, P = 0.04) and estimated glomerular filtration rate < 60 mL/min/1.73 m² (OR/CI: 4.34/1.94-9.73, P < 0.001). There existed a trend of a higher proportion of patients with significant SUA improvement along with the decrement of FIB-4 (29.7%, 25%, and 10.5% in patients with FIB-4 < 3.25, 3.25-6.5, and > 6.5, respectively; trend P = 0.03).

CONCLUSIONS

SUA levels were significantly decreased in chronic hepatitis C patients after viral eradication. The improvement was particularly enhanced in patients with mild liver disease.

Prediction model of artificial neural network for the risk of hyperuricemia incorporating dietary risk factors in a Chinese adult study

Background

Risk of hyperuricemia (HU) has been shown to be strongly associated with dietary factors. However, there is scarce evidence on prediction models incorporating dietary factors to estimate the risk of HU.

Objective

The aim of this study was to develop a prediction model to predict the risk of HU in Chinese adults based on dietary information.

Design

Our study was based on a cross-sectional survey, which recruited 1,488 community residents aged 18 to 60 years in Beijing from October 2010 to January 2011. The eligible participants were randomly divided into a training set (n₁ = 992) and a validation set (n₂ = 496) in the ratio of 2:1. We developed the prediction model in three stages. We first used a logistic regression model (LRM) based on the training set to select a set of dietary risk factors which were related to the risk of HU. Artificial neural network (ANN) was then used to construct the prediction model using the training set. Finally, we used receiver operating characteristic (ROC) curve analysis to assess the accuracy of the prediction model using training and validation sets.

Results

In the training set, the mean age of participants with and without HU was 39.3 (standard deviation [SD]: 9.65) and 38.2 (SD: 9.38) years, respectively. Patients with HU consisted of 101 males (77.7%) and 29 females (22.3%). The LRM found that food frequency (vegetables [odds ratio (OR) = 0.73], meat [0.72], eggs [0.80], plant oil [0.78], tea [0.51], eating habits (breakfast [OR = 1.28]), and the salty cooking style (OR = 1.33) were associated with risk of HU. In the ANN analysis, we selected a three-layer back propagation neural network (BPNN) model with 14, 3, and 1 neuron in the input, hidden, and output layers, respectively, as the best prediction model. The areas under the ROC of the training and validation sets were 0.827 and 0.814, respectively. HU would occur when the incidence probability is greater than 0.128. The indicators of accuracy, sensitivity, specificity, and Yuden Index suggested that the ANN model in our study is successful and valuable.

Conclusions

This study suggests that the ANN model could be used to predict the risk of HU in Chinese adults. Further prospective studies are needed to improve the accuracy and to generalize the use of model.

Hyperuricemia and Hypertension: Links and Risks

Hyperuricemia has long been recognized to be associated with increased cardiovascular risk, including risk of developing hypertension. Epidemiological findings suggest that the link with hypertension is stronger in children and adolescents. Uric acid acts as a strong antioxidant compound in the extracellular environment but has pro-inflammatory effects within the intracellular setting. A chronic phase of microvascular injury is known to occur after prolonged periods of hyperuricemia. This is proposed to contribute to afferent arteriolopathy and elevation of blood pressure that may become unresponsive to uric acid-lowering therapies over time. Studies have struggled to infer direct causality of hyperuricemia due to a vast number of confounders including body mass index. The aim of this review is to present the available data and highlight the need for large scale prospective randomized controlled trials in this area. At present, there is limited evidence to support a role for uric acid-lowering therapies in helping mitigate the risk of hypertension.

Intake of selected foods and beverages and serum uric acid levels in adults: ELSA-Brasil (2008–2010)

Objective:

To investigate the association between the intake of selected food groups and beverages and serum uric acid (UA).

Design:

Cross-sectional study using the baseline data (2008–2010) from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Food intake was assessed by food frequency questionnaire with 114 items. Linear and logistic regressions investigated the associations between the daily intake of each food group (servings/d) and UA (mg/dl) and hyperuricemia (UA ≥ 6·8 mg/dl), respectively. All the analyses were adjusted for potential confounders, energy intake and all food groups.

Setting:

Teaching and research institutions from six Brazilians states.

Subjects:

The participants were 14 320 active and retired civil servants, aged 35–74 years.

Results:

Higher intake of dairy products was associated with lower serum UA levels in both sexes, with a statistical dose-response gradient. High meat intake was associated with high UA only in women, and high intake of organ meats, in men. Intake of fish and fruits, vegetables and legumes were not associated with serum UA. In men, moderate and high intake of alcoholic beverages, specifically beer and spirits, but not wine, increased UA. In women, only high intake of alcoholic beverages, specifically beer, was associated with increased serum UA. Similar associations were seen for hyperuricemia.

Conclusions:

Results suggest a potential beneficial role of dairy products consumption on UA levels. The association between alcohol intake and UA differed according to type of beverage and between sexes. Results reinforce the need to consider the whole diet in the analysis and to conduct sex stratified analysis.

Epidemiology and prevalence of hyperuricemia among men and women in Chinese rural population: The Henan Rural Cohort Study

Objective: The aim of this study was to explore the latest prevalence of hyperuricemia and influencing factors in Chinese rural population.Methods: A survey was conducted from July 2015 to September 2017. A total of 38,855 (15,371 men and 23,484 women) subjects were recruited from the Henan Rural Cohort Study. Hyperuricemia was defined as a serum urate level of >7.0 mg/dL for men and >6.0 mg/dL for women. A meta-analysis of 19 studies that focused on hyperuricemia prevalence was performed to validate the result of the cross-sectional survey.Results: The crude and age-standardized prevalence of hyperuricemia was 10.24% and 12.60%, respectively. The prevalence of hyperuricemia decreased in men with increasing age, but the opposite trend was observed in women. The results of meta-analysis demonstrated that hyperuricemia prevalence in Chinese rural areas was 11.7%, consistent with the result of current survey. Multivariate logistic regression revealed that overweight or obesity, hypercholesterolemia, hypertriglyceridemia, hypoalphalipoproteinemia and high serum creatinine level could increase the risk of hyperuricemia, while high physical activity and fasting plasma glucose were associated with a lower risk of hyperuricemia in all participants.Conclusion: The latest prevalence of hyperuricemia is high in rural China and is associated with multiple factors, indicating that prevention and control strategies for hyperuricemia are needed urgently.

Dietary Antioxidant Supplements and Uric Acid in Chronic Kidney Disease: A Review

Increased serum levels of uric acid have been associated with the onset and development of chronic kidney disease (CKD), cardiovascular disease, and mortality, through several molecular pathogenetic mechanisms, such as inflammation and oxidative stress. Oxidative stress is present even in the early stages of CKD, progresses parallelly with the deterioration of kidney function, and is even more exacerbated in end-stage renal disease patients undergoing maintenance hemodialysis. Although acting in the plasma as an antioxidant, once uric acid enters the intracellular environment; it behaves as a powerful pro-oxidant. Exogenous intake of antioxidants has been repeatedly shown to prevent inflammation, atherosclerosis and oxidative stress in CKD patients. Moreover, certain antioxidants have been proposed to exert uric acid-lowering properties. This review aims to present the available data regarding the effects of antioxidant supplements on both oxidative stress and uric acid serum levels, in a population particularly susceptible to oxidative damage such as CKD patients.

Cross-sectional association between non-soy legume consumption, serum uric acid and hyperuricemia: the PREDIMED-Plus study

PURPOSE

To assess the association between the consumption of non-soy legumes and different subtypes of non-soy legumes and serum uric acid (SUA) or hyperuricemia in elderly individuals with overweight or obesity and metabolic syndrome.

METHODS

A cross-sectional analysis was conducted in the framework of the PREDIMED-Plus study. We included 6329 participants with information on non-soy legume consumption and SUA levels. Non-soy legume consumption was estimated using a semi-quantitative food frequency questionnaire. Linear regression models and Cox regression models were used to assess the associations between tertiles of non-soy legume consumption, different subtypes of non-soy legume consumption and SUA levels or hyperuricemia prevalence, respectively.

RESULTS

Individuals in the highest tertile (T3) of total non-soy legume, lentil and pea consumption, had 0.14 mg/dL, 0.19 mg/dL and 0.12 mg/dL lower SUA levels, respectively, compared to those in the lowest tertile (T1), which was considered the reference one. Chickpea and dry bean consumption showed no association. In multivariable models, participants located in the top tertile of total non-soy legumes [prevalence ratio (PR): 0.89; 95% CI 0.82-0.97; p trend = 0.01, lentils (PR: 0.89; 95% CI 0.82-0.97; p trend = 0.01), dry beans (PR: 0.91; 95% C: 0.84-0.99; p trend = 0.03) and peas (PR: 0.89; 95% CI 0.82-0.97; p trend = 0.01)] presented a lower prevalence of hyperuricemia (vs. the bottom tertile). Chickpea consumption was not associated with hyperuricemia prevalence.

CONCLUSIONS

In this study of elderly subjects with metabolic syndrome, we observed that despite being a purine-rich food, non-soy legumes were inversely associated with SUA levels and hyperuricemia prevalence.

TRIAL REGISTRATION

ISRCTN89898870. Registration date: 24 July 2014.

Beneficial Effect of Dietary Fiber on Hyperuricemia in Rats and Humans: A Review

Hyperuricemia is recognized as a lifestyle-related disease and the prevalence is increasing in many parts of the world. Excessive intake of purines increases serum uric acid concentration and is thought to be one factor causative of hyperuricemia. Therefore, it is thought that prevention of hyperuricemia by dietary control may be very important. This is an article of our basic research regarding the role of dietary fiber in the suppression of hyperuricemia induced by dietary purines in rats; in addition, clinical research suggesting the possibility that dietary fiber intake has a beneficial effect on the prevention or suppression of hyperuricemia in humans is discussed. Our own studies reveal that the test dietary fiber significantly suppresses the elevation of serum uric acid concentration induced by dietary RNA (12.3-46.2%), adenosine-5'-monophosphate (9.5-23.2%), adenosine (10.7-20.4%), or adenine (16.3-38.9%) and suppresses experimental hyperuricemia in rats. The mechanism is presumed to be mediated by suppression of the digestion and/or absorption of dietary purines by dietary fiber. In clinical studies, intake of dietary fiber decreases serum uric acid concentrations. Reports of recent epidemiological studies indicate that higher levels of hyperuricemia increase the prevalence of its comorbidities (e.g., chronic kidney disease, obesity, hypertension, diabetes, and cardiovascular disease) and dietary fiber intake is associated with significantly lower risk for hyperuricemia and its comorbidities. We wish to emphasize the importance of recognizing the validity of increased dietary fiber intake as a preventive or suppressive method for hyperuricemia and its comorbidities.

Natural compounds with xanthine oxidase inhibitory activity: A review

Hyperuricemia (HUA), a disease due to an elevation of body uric acid level and responsible for various diseases such as gout, cardiovascular disorders, and renal failure, is a major ground debate for the medical science these days. Considering the risk factors linked with allopathic drugs for the treatment of this disease, the debate has now become a special issue. Previously, we critically discussed the role of dietary polyphenols in the treatment of HUA. Besides dietary food plants, many researchers figure out the tremendous effects of medicinal plants-derived phytochemicals against HUA. Keeping in mind all these aspects, we reviewed all possible managerial studies related to HUA through medicinal plants (isolated compounds). In the current review article, we comprehensively discussed various bioactive compounds, chemical structures, and structure-activity relationship with responsible key enzyme xanthine oxidase.

Sugar-Sweetened Soft Drinks and Fructose Consumption Are Associated with Hyperuricemia: Cross-Sectional Analysis from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

The secular trend of hyperuricemia coincides with the substantial increase in the consumption of sugar-sweetened beverages. Our aim was to evaluate the association between the consumption of soft drinks, dietary fructose and unsweetened, non-processed fruit juices with hyperuricemia in a cross-sectional analysis of baseline data (2008⁻2010; n = 7173) of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). The explanatory variables were the consumption of soft drinks, fruit juice, and fructose using a validated semi-quantitative food frequency questionnaire. The outcomes were hyperuricemia and the uric acid concentration in serum. Regression models were tested, and a significance level of 5% was adopted. In men, the daily consumption of a portion of soft drink/day (250 mL) almost doubled the chance of hyperuricemia with a linear trend. In women, the consumption of ≥0.1 to <1.0 soft drink/day was associated with a higher chance of hyperuricemia, but there was no linear trend. High fructose consumption in men and moderate and high consumption in women were associated with hyperuricemia. All categories of soft drinks consumption were linearly associated with increased serum uric acid levels. Our findings suggest that the consumption of soft drinks and dietary fructose is positively associated with a higher chance of hyperuricemia and higher uric acid levels in Brazilian adults.

Dietary patterns associated hyperuricemia among Chinese aged 45 to 59 years: An observational study

In our literature research, we have not found any study reporting the association between the major dietary patterns and the risk of hyperuricemia in a middle-aged Chinese population. Herein, the present study aimed to evaluate the association of dietary patterns with the risk of hyperuricemia in the city of Hangzhou, Zhejiang Province, East China. We included 1204 participants (743 males and 461 females) aged 45 to 59 years in the present cross-sectional study. Dietary intake was assessed using a semiquantitative food frequency questionnaire in 2014 to 2016. All biochemical data and anthropometric measurements were collected following standardized procedures. Dietary patterns were determined by using factor analysis. We examined the associations between major dietary patterns and hyperuricemia risk by log-binominal regression analysis, and the results are presented as prevalence ratio (PR) and confidence interval (CI). Three major dietary patterns were identified by means of factor analysis: traditional Chinese, meat food, and mixed food patterns. After controlling for potential confounders, subjects in the highest quartile of the traditional Chinese pattern scores had a lower PR for hyperuricemia (PR = 0.82; 95%CI: 0.426-0.922), in comparison to those from the lowest quartile, while compared with the lowest quartile of the meat food pattern, the highest quartile had a greater PR for hyperuricemia (PR = 1.48; 95%CI: 1.120-2.097). Besides, no association was observed between mixed food pattern and the risk of hyperuricemia.Our findings indicate that the traditional Chinese pattern is associated with a decreased risk of hyperuricemia, and the meat food pattern is associated with an increased risk of hyperuricemia, whereas the mixed food pattern shows no association with the risk of hyperuricemia. Further large prospective studies are warranted to confirm our findings.

Proton-coupled electron transfer promotes the reduction of ferrylmyoglobin by uric acid under physiological conditions

Uric acid prevents the oxidative toxic effects of ferrylmyoglobin during red meat digestion.

Electropolymerized molecular imprinting on glassy carbon electrode for voltammetric detection of dopamine in biological samples

A simple and reliable method for preparing a selective dopamine (DA) sensor based on a molecularly imprinted polymer of ethacridine was proposed. The molecularly imprinted polymer electrode was prepared through electrodepositing polyethacridine-dopamine film on the glassy carbon electrode and then removing DA from the film via chemical induced elution. The molecular imprinted sensor was tested by cyclic voltammetry as well as by differential pulse voltammetry (DPV) to verify the changes in oxidative currents of DA. In optimized DPV conditions the oxidation peak current was well-proportional to the concentration of DA in the range from 2.0×10(-8)M up to 1×10(-6)M. The limit of detection (3σ) of DA was found to be as low as 4.4nM, by the proposed sensor that could be considered a sensitive marker of DA depletion in Parkinson's disease. Good reproducibility with relative standard deviation of 1.4% and long term stability within two weeks were also observed. The modified sensor was validated for the analysis of DA in deproteinized human serum samples using differential pulse voltammetric technique.

Natural Products Improving Hyperuricemia with Hepatorenal Dual Effects

This review aims to put forth an overview of natural products reducing uric acid level with hepatorenal dual effects. The prevalence of hyperuricemia increased rapidly in recent years and has closely interdependent relationship with other metabolic disorders. Current therapeutically used drugs including a few uricostatic and uricosuric chemical drugs are proved efficient to control serum uric acid level. However, their side effects as well as contraindication in some cases with liver, kidney injury, or other conditions frequently limit their clinic application. More attention thus has been paid to natural products as an alternative means in treating hyperuricemia. Many natural products have been proved efficient in downregulating uric acid level, among which some can improve hyperuricemia with hepatorenal dual effects. It means these natural products can regulate both the production and the excretion of uric acid by targeting the key metabolic enzymes mainly in liver or uric acid transporters in kidneys. Thus, these natural products could have stronger efficacy and broader application, which may be developed for the treatment of hyperuricemia in clinic.

Is coffee consumption associated with a lower risk of hyperuricaemia or gout? A systematic review and meta-analysis

OBJECTIVES

To examine the associations of coffee consumption with the serum uric acid (SUA) level, hyperuricaemia (HU) and gout.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

A comprehensive literature search up to April 2015, using PubMed and EMBASE databases, was conducted to identify the observational researches that examined the associations of coffee consumption with the SUA level, HU and gout. The standard mean difference (SMD), OR, relative risk (RR) and their corresponding 95% CIs for the highest and the lowest categories of coffee intake were determined.

RESULTS

A total of 11 observational studies (6 cross-sectional, 3 cohort and 2 case-control studies) were included in this systematic review and meta-analysis. The combined SMD suggested that there was no significant difference between the highest and the lowest coffee intake categories in terms of the SUA level (SMD=-0.09, 95% CI -0.23 to 0.05; p=0.21). Meanwhile, the overall multivariable adjusted OR for HU showed no significant difference between the highest and the lowest coffee intake categories (OR=0.84, 95% CI 0.65 to 1.09; p=0.20). However, the overall multivariable adjusted RR for gout showed a significant inverse association between coffee consumption and the incidence of gout (RR=0.43, 95% CI 0.31 to 0.59, p<0.001).

CONCLUSIONS

Current evidences are insufficient to validate the association between coffee consumption and a lower risk of HU. Owing to the limited number of studies, the available data show that coffee consumption may be associated with a lower risk of incident gout. Further well-designed prospective researches and randomised controlled trials are therefore needed to elaborate on these issues.

The association of vitamin C, alcohol, coffee, tea, milk and yogurt with uric acid and gout

About 2500 years ago, gout was observed by Hippocrates and many people suffered severe pain and deformity. Lifestyle and diet play a significant role in gout and serum uric acid levels. Epidemiological and research studies have supported this evidence. Many recommendations and guidelines from different parts of the world mention the impact of diet on gout. Recently, new research has shown associations between vitamin C, alcohol, coffee, tea, milk and yogurt with uric acid and the risk of gout. Our review summarizes recently published research regarding dietary impact on the risk of gout and serum uric acid levels.

Relationship between hyperuricemia and dietary risk factors in Chinese adults: a cross-sectional study

Previous studies focusing on identification of dietary risk factors for hyperuricemia reported controversial findings. Moreover, evidence for relationship between hyperuricemia and eating and cooking habits remained scanty. The purpose of this study was to evaluate the associations between hyperuricemia and dietary risk factors. A cross-sectional study was conducted among 1583 participants in a Beijing community. Face-to-face interviews were conducted using questionnaires. Anthropometric measurements and biochemical tests were also performed. The prevalence of hyperuricemia was 14.1 % (20.2 % for males and 7.4 % for females). Among the 1372 subjects included for analysis, 720 (52.5 %) were males and the mean age was 37.7 years. For males, statistically significant associations between hyperuricemia and tea intake, breakfast and midnight snack consumption were found, with an odds ratio of 0.56 (high vs. low), 2.14 (often vs. always) and 0.52 (rarely vs. always), respectively. Smoking, fatty liver disease, triglyceride, low-density lipoprotein cholesterol and fasting blood glucose were significantly related to increased serum uric acid (SUA), with a coefficient of 20.06, 11.52, 7.29, 18.97 and 13.37 on SUA, respectively. For females, no statistically significant associations between hyperuricemia and dietary risk factors were observed. In summary, hyperuricemia is highly prevalent among the adult participants in this Chinese community, especially for men. High tea intake and consuming midnight snack rarely are significantly related to decreased risk of hyperuricemia, while often-eating breakfast is associated with increased risk of hyperuricemia compared with always-eating breakfast in males. Further prospective studies are needed to confirm the findings and to establish dietary recommendations for the prevention and treatment of hyperuricemia.

Gout: a review of nonmodifiable and modifiable risk factors

Gout is a common inflammatory arthritis triggered by the crystallization of uric acid within the joints. Gout affects millions worldwide and has an increasing prevalence. Recent research has been carried out to better qualify and quantify the risk factors predisposing individuals to gout. These can largely be broken into nonmodifiable risk factors, such as gender, age, race, and genetics, and modifiable risk factors, such as diet and lifestyle. Increasing knowledge of factors predisposing certain individuals to gout could potentially lead to improved preventive practices. This review summarizes the nonmodifiable and modifiable risk factors associated with development of gout.

Sweetened beverage consumption and the risk of hyperuricemia in Mexican adults: a cross-sectional study

BACKGROUND

The prevalence of hyperuricemia has doubled worldwide during the last few decades. The substantial increase in sweetened beverage (SB) consumption has also coincided with the secular trend of hyperuricemia. Recent studies do show that the consumption of SB can induce hyperuricemia. However, the association between SB and hyperuricemia remains unclear. The aim of this study was to evaluate the association between SB consumption and levels of uric acid in Mexican adults.

METHODS

We performed a cross-sectional analysis of data from selected adults participating in the baseline assessment of the Health Workers Cohort Study. A total of 6,705 participants of both sexes between ages 18 and 70 years were included. SB intake was estimated using a validated semi-quantitative food frequency questionnaire. Biochemical and anthropometric information was collected using standard procedures. Hyperuricemia was defined as uric acid levels ≥ 7.0 mg/dL in men and ≥ 5.8 mg/dL in women. The association of interest was assessed by multiple logistic regression models.

RESULTS

The odds ratios (OR) for hyperuricemia in men who consume 0.5-1 SB/day was 1.59 (95% CI; 1.05-2.40) and 2.29 (95% CI; 1.55-3.38) for those who consume ≥3 SB/day when compared to men who consume less than half a SB/day. In women, the OR for hyperuricemia for those who consume >1.0- < 3.0 SB/day was 1.33 (95% CI; 1.04-1.70) and 1.35 (95% CI; 1.04-1.75) for those who consume ≥3 SB/day when compared to women who consume less than half a SB/day, independent of other covariables. Men and women with high SB consumption and a body mass index (BMI) ≥ 25 Kg/m2 had greater risk for hyperuricemia than men and women with low SB consumption and normal BMI < 25 Kg/m2.

CONCLUSIONS

Our findings suggest that the consumption of SB is associated with an increased risk of hyperuricemia in Mexican adults. However, longitudinal research is needed to confirm the association between SB intake and hyperuricemia.

Alcohol quantity and type on risk of recurrent gout attacks: an internet-based case-crossover study

OBJECTIVES

Although beer and liquor have been associated with risk of incident gout, wine has not. Yet anecdotally, wine is thought to trigger gout attacks. Further, how much alcohol intake is needed to increase the risk of gout attack is not known. We examined the quantity and type of alcohol consumed on risk of recurrent gout attacks.

METHODS

We conducted a prospective Internet-based case-crossover study in the US among participants with gout and who had at least one attack during the 1 year of follow-up. We evaluated the association of alcohol intake over the prior 24 hours as well as the type of alcoholic beverage with risk of recurrent gout attack, adjusting for potential time-varying confounders.

RESULTS

This study included 724 participants with gout (78% men, mean age 54 years). There was a significant dose-response relationship between amount of alcohol consumption and risk of recurrent gout attacks (P <.001 for trend). The risk of recurrent gout attack was 1.36 (95% confidence interval [CI], 1.00-1.88) and 1.51 (95% CI, 1.09-2.09) times higher for >1-2 and >2-4 alcoholic beverages, respectively, compared with no alcohol consumption in the prior 24 hours. Consuming wine, beer, or liquor was each associated with an increased risk of gout attack.

CONCLUSIONS

Episodic alcohol consumption, regardless of type of alcoholic beverage, was associated with an increased risk of recurrent gout attacks, including potentially with moderate amounts. Individuals with gout should limit alcohol intake of all types to reduce the risk of recurrent gout attacks.

Serum urate levels and consumption of common beverages and alcohol among Chinese in Singapore

OBJECTIVE

Western studies suggest that beverages may affect serum urate (SU) levels, but data from Asian populations are scarce. We evaluated the associations between beverages and SU levels in Singaporean Chinese.

METHODS

The study population consisted of 483 subjects ages 45-74 years from the Singapore Chinese Health Study cohort, recruited between 1993 and 1998. Lifestyle factors, medical histories, and diet were collected through in-person interviews. SU levels and other biomarkers were measured from blood collected between 1994 and 1996.

RESULTS

The mean age was 57.6 years and 44% were men. The geometric mean SU level was 321 μmoles/liter (range 157-719). Mean SU levels increased with alcohol consumption (P = 0.024 for trend). The mean SU level of daily alcohol drinkers was 42.6 μmoles/liter higher than that of nondrinkers. Similarly, increasing frequency of green tea intake was associated with rising SU levels. The highest mean SU level was observed in daily green tea drinkers (difference of 25.0 μmoles/liter) relative to nondrinkers (P = 0.009 for trend). Compared to nondrinkers, daily alcohol drinkers had an almost 5-fold increase in association with hyperuricemia (odds ratio [OR] 4.83, 95% confidence interval [95% CI] 1.10-21.23), whereas daily green tea drinkers had a 2-fold increase in association with hyperuricemia (OR 2.12, 95% CI 1.03-4.36). The present study did not show elevated levels of SU in individuals who consumed black tea, coffee, fruit juice, or soda.

CONCLUSION

Alcohol consumption increases SU levels. The finding that daily drinking of green tea is associated with hyperuricemia needs validation in future studies.

Dietary, anthropometric, and biochemical determinants of uric acid in free-living adults

BACKGROUND

High plasma uric acid (UA) is a prerequisite for gout and is also associated with the metabolic syndrome and its components and consequently risk factors for cardiovascular diseases. Hence, the management of UA serum concentrations would be essential for the treatment and/or prevention of human diseases and, to that end, it is necessary to know what the main factors that control the uricemia increase. The aim of this study was to evaluate the main factors associated with higher uricemia values analyzing diet, body composition and biochemical markers.

METHODS

415 both gender individuals aged 21 to 82 years who participated in a lifestyle modification project were studied. Anthropometric evaluation consisted of weight and height measurements with later BMI estimation. Waist circumference was also measured. The muscle mass (Muscle Mass Index - MMI) and fat percentage were measured by bioimpedance. Dietary intake was estimated by 24-hour recalls with later quantification of the servings on the Brazilian food pyramid and the Healthy Eating Index. Uric acid, glucose, triglycerides (TG), total cholesterol, urea, creatinine, gamma-GT, albumin and calcium and HDL-c were quantified in serum by the dry-chemistry method. LDL-c was estimated by the Friedewald equation and ultrasensitive C-reactive protein (CRP) by the immunochemiluminiscence method. Statistical analysis was performed by the SAS software package, version 9.1. Linear regression (odds ratio) was performed with a 95% confidence interval (CI) in order to observe the odds ratio for presenting UA above the last quartile (♂UA > 6.5 mg/dL and ♀ UA > 5 mg/dL). The level of significance adopted was lower than 5%.

RESULTS

Individuals with BMI ≥ 25 kg/m2 OR = 2.28(1.13-4.6) and lower MMI OR = 13.4 (5.21-34.56) showed greater chances of high UA levels even after all adjustments (gender, age, CRP, gamma-gt, LDL, creatinine, urea, albumin, HDL-c, TG, arterial hypertension and glucose). As regards biochemical markers, higher triglycerides OR = 2.76 (1.55-4.90), US-CRP OR = 2.77 (1.07-7.21) and urea OR = 2.53 (1.19-5.41) were associated with greater chances of high UA (adjusted for gender, age, BMI, waist circumference, MMI, glomerular filtration rate, and MS). No association was found between diet and UA.

CONCLUSIONS

The main factors associated with UA increase were altered BMI (overweight and obesity), muscle hypotrophy (MMI), higher levels of urea, triglycerides, and CRP. No dietary components were found among uricemia predictors.

Alcohol intake and the risk of hyperuricaemia: a 6-year prospective study in Japanese men

BACKGROUND AND AIMS

Since there is little information derived from prospective studies on the amount of alcohol drinking required to induce hyperuricaemia, we attempted to address this issue in a Japanese population.

METHODS AND RESULTS

A total of 3310 Japanese men aged 20-54 years that were free of hyperuricaemia were classified according to their alcohol intake per week at baseline. Incident hyperuricaemia, defined as >7.0 mg/dl and/or taking medication for hyperuricaemia, was assessed through annual heath examinations for 6 years after the baseline examination. During follow-up, 529 incident cases of hyperuricaemia occurred. There was a positive, dose-response relationship between alcohol intake and the risk of incident hyperuricaemia. The hazard ratio (95% confidence interval) for hyperuricaemia in drinkers compared with non-drinkers was 1.10 (0.85-1.42) for <10.0 drinks/week, 1.40 (1.07-1.84) for 10.0-19.9 drinks/week, 1.64 (1.23-2.21) for 20.0-29.9 drinks/week and 1.98 (1.40-2.80) for ≥30.0 drinks/week (one drink contained 11.5 g of ethanol) after adjusting for age, baseline serum uric acid, body mass index, smoking habits, exercise habits, serum creatinine, blood pressure, serum cholesterol and blood glucose. The fraction of hyperuricaemia in the population attributable to alcohol intake was 21.6%. A clear dose-response pattern was observed for both beer and sake, when the consumption of these two beverages was analysed separately.

CONCLUSION

Habitual alcohol intake significantly contributed to the development of hyperuricaemia in Japanese men, regardless of type of alcoholic beverage consumed. Therefore, it is essential to reduce excessive alcohol intake to prevent and manage hyperuricaemia.

Purine-rich foods, protein intake, and the prevalence of hyperuricemia: the Shanghai Men's Health Study

BACKGROUND AND AIMS

Diet may play an important role in the development of hyperuricemia and gout. However, the association between dietary factors and hyperuricemia remains unclear, and few studies have investigated direct links between food intake and hyperuricemia. The aim of this study was to investigate associations between high purine-content foods and protein intake with the prevalence of hyperuricemia by using data from a cross-sectional study of 3978 men aged 40-74 yrs living in Shanghai, China.

METHODS AND RESULTS

Hyperuricemia was defined as blood uric acid level >7.0 mg/dl. One quarter of this population had hyperuricemia. Dietary information was collected by using a food frequency questionnaire. We collected information on anthropometric measurements and lifestyle factors and other potential confounding factors and disease history via interviews. Total protein consumption was not associated with hyperuricemia. We found a positive association between protein from animal sources and prevalence of hyperuricemia and an inverse association between protein from plant sources and hyperuricemia. However, these associations failed to reach significance in mutually adjusted analysis. Seafood intake was associated with higher prevalence of hyperuricemia. The ORs for quintiles of seafood intake (including fish and shellfish) were 1.00, 1.49, 1.35, 1.34, and 1.56 (p for trend: 0.01). An inverse association approaching significance between soy food consumption and hyperuricemia was observed (ORs: 1.00, 0.90, 0.70, 0.89, and 0.77 for quintiles of intake; p for trend: 0.07). No associations between consumption of purine-rich vegetables or meat and prevalence of hyperuricemia were observed.

CONCLUSIONS

Our data suggest a direct association between seafood consumption and hyperuricemia and an inverse association between consumption of soy food and hyperuricemia among middle-aged, Chinese men.