Uric Acid and Potassium Serum Levels Are Independent Predictors of Blood Pressure Non-Dipping in Overweight or Obese Subjects

Dietary Factors and Risk of Gout: A Two-Sample Mendelian Randomization Study

BACKGROUND

Dietary intervention is the preferred approach for the prevention and clinical management of gout. Nevertheless, the existing evidence regarding the influence of specific foods on gout is insufficient.

METHODS

We used two-sample Mendelian randomization for genetic prediction to analyze the relationship between the intake of more than a dozen daily food items, such as pork, beef, cheese, and poultry, and dietary macronutrient intake (fat, protein, carbohydrates, and sugar) and the risk of developing gout and elevating the serum uric acid level. Inverse-variance weighted MR analyses were used as the main evaluation method, and the reliability of the results was tested by a sensitivity analysis.

RESULTS

Cheese intake was associated with lower serum uric acid levels, and tea intake (OR = 0.523, [95%CI: 0.348~0.784], p = 0.002), coffee intake (OR = 0.449, [95%CI: 0.229~0.882], p = 0.020), and dried fruit intake (OR = 0.533, [95%CI: 0.286~0.992], p = 0.047) showed a preventive effect on the risk of gouty attacks. In contrast, non-oily fish intake (β = 1.08, [95%CI: 0.24~1.92], p = 0.012) and sugar intake (β = 0.34, [95%CI: 0.03~0.64], p = 0.030) were risk factors for elevated serum uric acid levels, and alcohol intake frequency (OR = 1.422, [95%CI: 1.079~1.873], p = 0.012) was a risk factors for gout predisposition.

CONCLUSIONS

These results will significantly contribute to the formulation and refinement of nutritional strategies tailored to patients afflicted with gout.

Estimation of elemental concentrations in the toenail of young Saudi females with obesity

Elemental homeostasis is essential for maintaining normal metabolic processes. Elements in the toenails are now considered in the diagnosis or screening and used as biomarkers of several metabolic disorders. The incidence of obesity is more prevalent in females than males globally. At the same time, females appeared more susceptible to elemental alterations than males. This study aimed to evaluate the variation in the levels of several elements in toenails as possible biomarkers of health conditions associated with obesity in young Saudi females. A cross-sectional study was performed, between February–November 2019. The study enrolled 79 young females divided into two groups: participants with obesity (n=39) and non-obese (n=40). The toenail was analyzed to estimate Fe, I, K, Na, Cd, Cr, Mn, Ca, Mg, Cu, Co, and Se levels. The study showed a significant elevation in the levels of Fe, Ca, K, and Na in the toenail sample of female participants with obesity compared to the non-obese group. The levels of Mn, Cd, Co, Cu, and Cr, were significantly decreased in the toenail of participants with obesity. Moreover, other elements (i.e., Mg, I, and Se) were not significantly lower in the female group with obesity. Our findings confirmed the alterations of several elements among Saudi females with obesity. The toenail elemental analysis may become a useful diagnostic technique in monitoring the nutritional status, predicting some metabolic disorders, and environmental exposure.

Variation in serum urate levels in the absence of gout and urate lowering therapy

BACKGROUND

Previous studies have noted significant variation in serum urate (sUA) levels, and it is unknown how this influences the accuracy of hyperuricemia classification based on single data points. Despite this known variability, hyperuricemic patients are often used as a control group in gout studies. Our objective was to determine the accuracy of hyperuricemia classifications based on single data points versus multiple data points given the degree of variability observed with serial measurements of sUA.

METHODS

Data was analyzed from a cross-over clinical trial of urate-lowering therapy in young adults without a gout diagnosis. In the control phase, sUA levels used for this analysis were collected at 2-4 week intervals. Mean coefficient of variation for sUA was determined, as were rates of conversion between normouricemia (sUA ≤6.8 mg/dL) and hyperuricemia (sUA > 6.8 mg/dL).

RESULTS

Mean study participant (n = 85) age was 27.8 ± 7.0 years, with 39% female participants and 41% African-American participants. Mean sUA coefficient of variation was 8.5% ± 4.9% (1 to 23%). There was no significant difference in variation between men and women, or between participants initially normouricemic and those who were initially hyperuricemic. Among those initially normouricemic (n = 72), 21% converted to hyperuricemia during at least one subsequent measurement. The subgroup with initial sUA < 6.0 (n = 54) was much less likely to have future values in the range of hyperuricemia compared to the group with screening sUA values between 6.0-6.8 (n = 18) (7% vs 39%, p = 0.0037). Of the participants initially hyperuricemic (n = 13), 46% were later normouricemic during at least one measurement.

CONCLUSION

Single sUA measurements were unreliable in hyperuricemia classification due to spontaneous variation. Knowing this, if a single measurement must be used in classification, it is worth noting that those with an sUA of < 6.0 mg/dL were less likely to demonstrate future hyperuricemic measurements and this could be considered a safer threshold to rule out intermittent hyperuricemia based on a single measurement point.

TRIAL REGISTRATION

Data from parent study ClinicalTrials.gov Identifier: NCT02038179 .

Association of hyperuricemia and hypertension phenotypes in hypertensive patients without uric acid lowering treatment

BACKGROUND

Current study was to evaluate the association of hypertensive and hypertension phenotypes in hypertensive populations.

METHODS

Patients with primary hypertension and without any uric acid (UA)-lowering treatment were enrolled. Baseline characteristics including office blood pressure (OBP), 24 h ambulatory blood pressure (ABP), and serum UA (SUA) were measured. According to SUA, patients were divided into normal SUA and hyperuricemia groups. Based on OBP and 24 h-ABP, hypertension phenotypes were classified as controlled hypertension (CH), white-coat uncontrolled hypertension (WCUH), masked uncontrolled hypertension (MUCH), and sustained uncontrolled hypertension (SUCH).

RESULTS

Compared to patients with normal SUA (n = 336), patients with hyperuricemia (n = 284) were older and more likely to be men, obese, physically inactive, and have a higher prevalence of diabetes. C-reactive protein (CRP) level was higher in patients with hyperuricemia. The prevalence of CH, WCUH, and MUCH was similar between these two groups. However, the prevalence of SUCH was higher in patients with hyperuricemia than patients with normal SUA. Linear regression analysis indicated that increased SUA was significantly associated with 24 h-systolic BP and daytime-systolic BP. Normal SUA was served as the reference group, and presence of hyperuricemia was associated with higher odds of SUCH (odds ratio 1.46 and 95% confidence interval 1.27-1.93) after adjusted for potential covariates including age, male gender, obesity, diabetes, CRP, and antihypertensive drugs.

CONCLUSION

In hypertensive patients without UA-lowering treatment, presence of hyperuricemia was associated with higher odds of SUCH. Future studies are needed to evaluate whether lowering SUA can help to improve 24 h-ABP control.

The Association of Serum Uric Acid with Beta-Cell Function and Insulin Resistance in Nondiabetic Individuals: A Cross-Sectional Study

PURPOSE

Higher serum levels of uric acid (SUA) are associated with an increased risk of developing type 2 diabetes. Meanwhile, insulin resistance and beta-cell dysfunction are critical factors that mediate the progression from normal glucose tolerance to impaired fasting glucose (IFG) and type 2 diabetes. We aimed to investigate the association between SUA levels and insulin resistance and beta-cell dysfunction in individuals without diabetes, thus explicating the role of uric acid in the early stage of the natural history of type 2 diabetes.

PATIENTS AND METHODS

We used cross-sectional data from the China Health and Nutrition Survey to examine the association. Insulin resistance and beta-cell dysfunction were estimated using the homeostasis model assessment of insulin resistance (HOMA-IR) index and homeostasis model assessment of beta-cell function (HOMA-beta) index, respectively. The associations were analyzed by using partial correlation analysis and multivariate logistic regressionl analysis.

RESULTS

SUA levels were positively associated with fasting glucose, fasting insulin, HOMA-IR in the total population. After adjustment for age, drinking, smoking, living area, daily dietary nutrient intake, body mass index (BMI), estimated glomerular filtration rate (eGFR), hypertension, and dyslipidemia, compared with participants in the lowest quartile of SUA, the adjusted odds ratios for the fourth quartiles were 1.56(1.09-2.24) for IFG, 1.51(1.27-1.78) for insulin resistance, and 1.06(0.88-1.27) for beta-cell dysfunction. In the subgroup analysis, no interactions were found between serum uric acid and age, drinking status, smoking status, BMI, hypertension, or dyslipidemia (all p for interaction>0.05).

CONCLUSION

In nondiabetic individuals, SUA levels are independently associated with IFG and insulin resistance, while no significant association exists between SUA and beta-cell dysfunction.

Dietary Habits and Nutrient Intakes Are Associated to Age-Related Central Auditory Processing Disorder in a Cohort From Southern Italy

Objectives

Central auditory processing disorder (CAPD) commonly occurs in older age. However, few studies of a possible link between age-related CAPD and diet in an older population have been conducted. The objective of the present study was to investigate the relationship between eating habits and age-related CAPD in a population >65 years, using cross-sectional and retrospective data obtained in the same population-based study about 12 years ago.

Methods

We selected 734 participants (403 men) from a large population-based study. For age-related CAPD assessment, we used the Synthetic Sentence Identification with Ipsilateral Competitive Message test. Dietary habits were assessed by a Food Frequency Questionnaire. Associations between age-related CAPD and food groups/macro-and micronutrients were explored using adjusted logistic regression models.

Results

Age-related CAPD subjects consumed more dairy (111 vs. 98 g/d), olives and vegetable oil (63 vs. 52 g/d) and spirits (2 vs.1 g/d), and less fruits (536 vs. 651 g/d) in the cross-sectional analysis. Age-related CAPD subjects had a lower intake of potassium, vitamin C, and a higher fat intake. Further analyses identified dietary fiber as being inversely related to age-related CAPD.

Discussion

The present study provided evidence that the dietary hypotheses proposed for explaining the development of cognitive disorders in older age might also hold for age-related CAPD. Further data from other large and prospective population-based studies are needed for confirming these findings.

Impaired fasting plasma glucose is a risk indicator of interventricular septum thickening among non-diabetic subjects with obesity

AIMS

To evaluate whether progressively higher fasting plasma glucose (FPG) is associated to thickening of the interventricular septum (IVS) among non-diabetic subjects with obesity.

METHODOLOGY

We studied 227 consecutive non diabetic patients (155 women and 72 men, age range 18-72 years) with overweight or obesity (BMI ≥ 25 Kg/m2), taking no medication or supplement. Hormonal, metabolic and routine laboratory parameters were collected. Echocardiography and ultrasonography echo-color Doppler of intima-media thickness of the common carotid artery (IMT-CCA) were performed to evaluate intima-media thickness of the common carotid artery (IVST) and early signs of atherosclerosis, respectively, in all enrolled subjects.

RESULTS

Of the 227 subjects, 48.9% had higher IVST values. Age (p 0.04), waist circumference (p 0.01), systolic (p < 0.01) and diastolic blood pressure (p < 0.01), FPG (p < 0.01), insulin (p 0.04), HOMA IR (p = 0.01), uric acid (p < 0.01) serum levels, IMT-CCA (p < 0.01), and left atrial diameter (LAD) (p < 0.01) were significantly higher in subjects with pathological IVST. Logistic regression models demonstrated an independent relation of FPG to IVST, both in semi and fully adjusted models (ORs 1.045 and 1.039, respectively). Moreover, graph presentation of the ORs and 95% CIs by FPG quintiles showed a positive risk trend for pathological IVST.

CONCLUSIONS

Higher FPG levels represent an independent sensitive predictor of IVS thickening in subjects with obesity, even before overt diabetes. These results emphasize the importance of preventive management of the diabetes risk in obesity.

Urine Glucose Excretion Attenuates the Association Between Lipid Accumulation Product and Serum Uric Acid in Subjects with Prediabetes

PURPOSE

Obesity is known to be strongly associated with hyperuricemia. Moreover, the impact of urine glucose excretion (UGE) on serum uric acid (UA) levels has gained much more attention in recent years. Yet concern is raised about whether UGE influences the relationship between obesity and hyperuricemia. The aim of this study was to assess the effect of UGE on the association between lipid accumulation product (LAP), a novel marker of visceral adipose accumulation, and UA in subjects with prediabetes.

MATERIALS AND METHODS

Data were obtained from a cross-sectional study. A total of 3645 subjects with prediabetes were included in the present study. The separate and joint associations of LAP and UGE with hyperuricemia were examined using logistic regression analyses.

RESULTS

LAP was positively associated with UA in both genders. Subgroup analysis based on UGE revealed that the association was strongest in subjects with low UGE (r = 0.328, p < 0.001), whereas the positive association was weakened, but still remained significant in subjects with moderate and high UGE. High LAP was significantly associated with an increased odds ratio for hyperuricemia after adjustment for potential confounders in the overall population (OR = 2.07, 95% CI: 1.66-2.58, p < 0.001). However, a downward trend in odds ratios for hyperuricemia was observed across UGE categories. In addition, the joint association analysis confirmed that the relationship between LAP and hyperuricemia was attenuated by UGE.

CONCLUSION

The positive association between LAP and UA appears to be attenuated by UGE, indicating that promoting UGE may be an effective strategy for controlling UA levels, especially for people with obesity who are at increased risk for hyperuricemia.

Sex-Specific Associations of Circulating Uric Acid with Risk of Diabetes Incidence: A Population-Based Cohort Study from Sweden

OBJECTIVE

To explore the longitudinal, as well as sex-specific, associations between circulating uric acid (UA) and diabetes incidence.

METHODS

A cohort study of the Malmö Diet Cancer-cardiovascular Cohort (Malmö, Sweden) consisting of 3140 individuals without diabetes at baseline, was followed up until the end of 2018. Incident diabetes cases were identified by linking to local and national diabetes registers. Cox proportional hazard regression was used to assess plasma UA levels in relation to diabetes incidence with adjustment for established confounders.

RESULTS

At baseline, with increasing levels of UA, subjects were more likely to be older and have significantly higher body mass index, waist circumference, triglycerides, C-reactive protein, fasting glucose and 2-h plasma glucose postoral glucose tolerance test, and lower levels of high-density lipoprotein. During a mean follow-up period of 8.09±2.24 years, 315 (10.0%) participants developed diabetes, and diabetes incidence rates were 7.89, 9.48 and 18.11 per 1000 person-years for subjects in the 1st, 2nd, and 3rd tertiles of UA, respectively (log-rank test: p<0.001). With adjustment for potential confounders, elevated UA levels were significantly associated with increased risks of diabetes incidence, with the adjusted hazard ratio (HR) (95% confidence interval) for per standard deviation increment of UA of 1.22 (1.08-1.39, p=0.002). Compared with the 1st tertile of UA, the 3rd tertile showed significantly increased risk of diabetes incidence with the adjusted HR of 1.74 (1.24-2.45, p=0.002), and there was a significant trend between increasing tertiles of UA and diabetes incidence (trend test: p<0.001). Stratified analyses showed that elevated circulating UA levels were independently associated with increased risks of diabetes incidence in men but not in women, although the interaction between sex and UA was not statistically significant.

CONCLUSION

Elevated circulating UA was independently associated with increased risk of diabetes incidence, especially for men.

Correlation Between Serum Uric Acid Level and Central Body Fat Distribution in Patients with Type 2 Diabetes

BACKGROUND

The aim of this study was to investigate the correlation between serum uric acid level and central body fat distribution in patients with type 2 diabetes (T2DM).

METHODS

A total of 867 patients with T2DM were enrolled. Measurements of central fat distribution were obtained by dual energy X-ray absorptiometry. Patients were stratified into three groups according to their levels of serum uric acid (SUA). Multiple linear regression analysis was used to determine the association between SUA and central body fat distribution. Logistic regression analysis was used to estimate the risk factors for hyperuricemia (HUA). Mediation analysis was applied to assess the overall, direct, and indirect mediators of SUA levels.

RESULTS

Multiple linear regression analysis showed that SUA levels were significantly positively correlated with waist circumference (WC), body mass index (BMI), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), Android fat mass, Gynoid fat mass, fasting c-peptide (F-CP), and area under the curve of C-peptide (P < 0.05 for all). VAT [odds ratio (OR), 2.367; 95% confidence interval (CI), 1.078-5.197; P < 0.001)], WC (OR, 1.041; 95% CI, 1.011-1.072; P < 0.001), high-density lipoprotein (OR, 0.274; 95% CI, 0.104-0.727; P < 0.001), and estimated glomerular filtration rate (OR, 0.966; 95% CI, 0.959-0.973; P < 0.001) were found to be independent risk factors for T2DM patients with HUA. After mediation analysis, BMI and central obesity were found to have different partial effects on the association between SUA and F-CP (P < 0.001).

CONCLUSION

In patients with T2DM, HUA was positively correlated with F-CP and central body fat distribution, especially VAT. These results suggest that central obesity may play a role in the positive correlation between HUA and insulin resistance (IR).