Folic acid therapy reduces serum uric acid in hypertensive patients: a substudy of the China Stroke Primary Prevention Trial (CSPPT)

Exploring the causal associations of micronutrients on urate levels and the risk of gout: A Mendelian randomization study

BACKGROUND & AIMS

Growing evidence has indicated a potential association between micronutrient levels, urate levels, and the risk of gout. However, the causal association underlying these associations still remains uncertain. Previous observational studies and randomized controlled trials investigating the association between micronutrients, urate levels, and the risk of gout have been limited in their scope and depth. The aim of this study was to utilize Mendelian randomization (MR) to investigate the causal associations between genetically predicted micronutrient levels, urate levels, and the risk of gout.

METHODS

In this study, we conducted a comprehensive examination of 10 specific micronutrients (vitamin B6, vitamin B12, vitamin C, vitamin D, folate, calcium, iron, copper, zinc, and selenium) as potential exposures. Two-sample MR analyses were performed to explore their causal associations with urate levels and the risk of gout. In these analyses, gout data were collected from the Global Biobank Meta-Analysis Initiative (N = 1,069,839, N cases = 30,549) and urate levels data from CKDGen Consortium (N = 288,649) by utilizing publicly available summary statistics from independent cohorts of European ancestry. We performed inverse-variance weighted MR analyses as main analyses, along with a range of sensitivity analyses, such as MR-Egger, weighted median, simple mode, weighted mode, Steiger filtering, MR-PRESSO, and Radial MR analysis, to ensure the robustness of our findings.

RESULTS

The results of our study indicate that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout. Specifically, we found a negative association between vitamin B12 levels and urate levels, with a β coefficient of -0.324 (95% CI -0.0581 to -0.0066, P = 0.0137) per one standard deviation (SD) increase. Similarly, a negative association was observed between folate levels and gout risk, with an odds ratio of 0.8044 (95% CI 0.6637 to 0.9750, P = 0.0265) per one SD increase. On the other hand, we identified positive associations between serum calcium levels and both urate levels and the risk of gout. Specifically, there was a positive association between serum calcium levels and urate levels (β coefficient: 0.0994, 95% CI 0.0519 to 0.1468, P = 4.11E-05) per one SD increase. Furthermore, a positive association was found between serum calcium levels and the risk of gout, with an odds ratio of 1.1479 (95% CI 1.0460 to 1.2598, P = 0.0036) per one SD increase. These findings were robust in extensive sensitivity analyses. By employing MR-PRESSO and Radial MR to eliminate outliers, the observed associations have been reinforced. No clear associations were found between the other micronutrients and the urate levels, as well as the risk of gout.

CONCLUSION

Our findings provided evidence that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout, while positive associations existed between the serum calcium levels and urate levels, as well as the risk of gout.

Evaluation of plasma vitamin E and development of proteinuria in hypertensive patients

Background

The prospective relationship between plasma vitamin E levels and proteinuria remains uncertain. We aimed to evaluate the association between baseline plasma vitamin E levels and the development of proteinuria and examine any possible effect modifiers in patients with hypertension.

Methods

This was a post hoc analysis of the renal sub-study of the China Stroke Primary Prevention Trial (CSPPT). In total, 780 participants with vitamin E measurements and without proteinuria at baseline were included in the current study. The study outcome was the development of proteinuria, defined as a urine dipstick reading of a trace or ≥ 1+ at the exit visit.

Results

During a median follow-up duration of 4.4 years, the development of proteinuria occurred in 93 (11.9%) participants. Overall, there was an inverse relationship between plasma vitamin E and the development of proteinuria (per standard deviation [SD] increment; odds ratio [OR]: 0.73, 95% confidence interval [CI]: 0.55-0.96). Consistently, when plasma vitamin E was assessed as quartiles, lower risk of proteinuria development was found in participants in quartiles 2-4 (≥ 7.3 μg/mL; OR: 0.57, 95% CI: 0.34-0.96) compared to those in quartile 1. None of the variables, including sex, age, and body mass index, significantly modified the association between vitamin E and proteinuria development.

Conclusion

There was a significant inverse association between plasma vitamin E levels and the development of proteinuria in patients with hypertension. The results were consistent among participants with different baseline characteristics.

The Management of Diabetes with Hyperuricemia: Can We Hit Two Birds with One Stone?

Serum urate (SU) is an independent predictor for the incidence of diabetes. In current diabetes treatment regimens, there is insufficient appreciation of the importance of hyperuricemia (HU) in disease control and prevention. To summarize the updated knowledge on the effects of SU on β-cell function, insulin resistance and chronic diabetic complications, as well as to evaluate the management of patients with both HU and diabetes, we searched the MEDLINE PubMed database, and included 285 journal articles. An inverted U-shaped relationship between fasting plasma glucose and SU levels was established in this review. Elevated SU levels may enhance the development of chronic diabetic complications, including macrovascular and microvascular dysfunction. Diet and exercise are essential parts of the lifestyle changes necessary for HU and diabetes management. Glucose- and urate-lowering drug selection and combination should be made with the principle of ameliorating, and at least not deteriorating, diabetes and HU. Medical artificial intelligence technology and monitoring systems can help to improve the effectiveness of long-term management of HU and diabetes through digital healthcare. This study comprehensively reviews and provides a scientific and reliable basis for and viewpoints on the clinical management of diabetes and HU.

Pharmaceutical care model in precision medicine in China

Pharmacy service is to provide individualized pharmaceutical care for patients, which should follow the current evidence-based pharmacy, and constantly verify the evidence and then produce new evidence. In pharmaceutical care, differences are often found in the efficacy and adverse reactions of drugs among individuals, even within individuals, which are closely related to patients' genetics, liver and kidney functions, disease states, and drug interactions. Back in the 1980s, therapeutic drug monitoring (TDM) has been applied to routinely monitor the blood drug concentration of patients taking antiepileptic drugs or immunosuppressants after transplantation to provide individualized dosage recommendations and accumulate a large amount of pharmacokinetic (PK)/pharmacodynamic (PD) data. As individualized pharmaceutical care proceeds, the concept of precision medicine was introduced into pharmacy services in combination with evidence-based pharmacy, PK/PD theories, and big data to further promote the TDM technology and drugs, and carry out pharmacogenomics analysis. The TDM and pharmacogenomics have been applied gradually to the fields of antimicrobial, antitumor, and antipsychotic drugs and immunosuppressants. Based on the concept of precision pharmacy, we adopted approaches including PK/PD, quantitative pharmacology, population pharmacokinetics, and big data machine learning to provide more personalized pharmacy services, which is mainly for special patients, such as critical patients, patients with interaction risk of multiple drugs, patients with liver and renal insufficiency, pregnant women, children, and elderly patients. As the service pattern of precision pharmacy has been constructed and constantly improved, better evidence in clinical practice will be produced to provide patients with better precision pharmacy service.

Pharmaceutical care model in precision medicine in China

Pharmacy service is to provide individualized pharmaceutical care for patients, which should follow the current evidence-based pharmacy, and constantly verify the evidence and then produce new evidence. In pharmaceutical care, differences are often found in the efficacy and adverse reactions of drugs among individuals, even within individuals, which are closely related to patient's genetics, liver and kidney functions, disease states, and drug interactions. Back in the 1980s, therapeutic drug monitoring (TDM) has been applied to routinely monitor the blood drug concentration of patients taking antiepileptic drugs or immunosuppressants after transplantation to provide individualized dosage recommendations and accumulate a large amount of pharmacokinetic (PK)/pharmacodynamic (PD) data. As individualized pharmaceutical care proceeds, the concept of precision medicine was introduced into pharmacy services in combination with evidence-based pharmacy, PK/PD theories and big data to further promote the TDM technology and drugs, and carry out pharmacogenomics analysis. The TDM and pharmacogenomics have been applied gradually to the fields of antimicrobial, antitumor and antipsychotic drugs and immunosuppressants. Based on the concept of precision pharmacy, we adpoted approaches including PK/PD, quantitative pharmacology, population pharmacokinetics, and big data machine learning to provide more personalized pharmacy services, which is mainly for special patients, such as critical patients, patients with interaction risk of multiple drugs, patients with liver and renal insufficiency, pregnant women, children and elderly patients. As the service pattern of precision pharmacy has been constructed and constantly improved, better evidence in clinical practice will be produced to provide patients with better precision pharmacy service.

Positive correlation between hypertensive retinopathy and albuminuria in hypertensive adults

PURPOSE

We investigated the association between albuminuria and hypertensive retinopathy (HR) in hypertensive adults.

METHODS

This was a cross-sectional subgroup analysis of data from the China Stroke Primary Prevention Trial. We enrolled 2,964 hypertensive adults in this study. Keith-Wagener-Barker stages was used to assess HR. The urinary albumin to creatinine ratio (UACR) was calculated to evaluate albuminuria.

RESULTS

HR was found in 76.6% (n = 2, 271) of the participants, albuminuria was found in 11.1% (n = 330). The UACR levels were significantly higher in subjects with HR than in those without HR (grade 1, β = 1.42, 95% confidence intervals [CI]: -0.12, 2.95, p = 0.070; grade 2, β = 2.62, 95% CI: 0.56, 4.67, p = 0.013; grade 3, β = 5.17, 95% CI: 1.13, 9.20, p = 0.012). In the subgroup analyses, the association between HR and UACR was stronger in current smokers (p for interaction = 0.014). The correlation between HR grades 1 and 2 and UACR was stronger in subjects with higher triglyceride levels (≥ 1.7 mmol/L), but for grade 3 HR, this correlation was stronger in subjects with lower triglycerides levels (< 1.7 mmol/L, p for interaction = 0.023). The odds of albuminuria were significantly higher in subjects with HR than in those without HR (grade 1, odds ratio [OR] = 1.57, 95% CI: 1.08, 2.29, p = 0.019; grade 2, OR = 2.02, 95% CI: 1.28, 3.18, p = 0.002; grade 3, OR = 2.12, 95% CI: 0.99, 4.55, p = 0.053). In the subgroup analyses, the association between HR grades 1 and 2 and albuminuria was stronger in subjects with higher triglycerides levels (≥ 1.7 mmol/L), but for grade 3 HR, this correlation was stronger in subjects with lower triglyceride levels (< 1.7 mmol/L, p for interaction = 0.014).

CONCLUSION

HR was positively correlated with albuminuria in hypertensive Chinese adults. This correlation was more remarkable when the population was stratified by triglycerides levels and smoking status. HR can be used as an indicator of early renal injury.

Folic Acid Protects against Hyperuricemia in C57BL/6J Mice via Ameliorating Gut-Kidney Axis Dysfunction

Emerging lines of research evidence point to a vital role of gut-kidney axis in the development of hyperuricemia (HUA), which has been identified as an increasing burden worldwide due to the high prevalence. The involved crosstalk which links the metabolic and immune-related pathways is mainly responsible for maintaining the axial homeostasis of uric acid (UA) metabolism. Nowadays, the urate-lowering drugs only aim to treat acute gouty arthritis as a result of their controversial clinical application in HUA. In this study, we established the HUA model of C57BL/6J mice to evaluate the effectiveness of folic acid on UA metabolism and further explored the underlying mechanisms. Folic acid attenuated the kidney tissue injury and excretion dysfunction, as well as the typical fibrosis in HUA mice. Molecular docking results also revealed the structure-activity relationship of the folic acid metabolic unit and the UA transporters GLUT9 and URAT1, implying the potential interaction. Also, folic acid alleviated HUA-induced Th17/Treg imbalance and intestinal tissue damage and inhibited the active state of the TLR4/NF-κB signaling pathway, which is closely associated with the circulating LPS level caused by the impaired intestinal permeability. Furthermore, the changes of intestinal microecology induced by HUA were restored by folic acid, including the alteration in the structure and species composition of the gut microbiome community, and metabolite short-chain fatty acids. Collectively, this study revealed that folic acid intervention exerted improving effects on HUA by ameliorating gut-kidney axis dysfunction.

Association between nutrient patterns and hyperuricemia: mediation analysis involving obesity indicators in the NHANES

Background

Diet has long been hypothesized to play an important role in hyperuricemia, and weight gain is a factor that is strongly associated with the rise in serum urate. We aimed to clarify the mediating role of obesity in the relationship between diet and hyperuricemia and to determine whether a weight-loss diet is an effective way to prevent hyperuricemia.

Methods

This cross-sectional study analysed representative samples of United States (n = 20,081; NHANES 2007–2016) adults. Nutrient patterns were derived with two methods: principal component analysis (PCA) and reduced rank regression (RRR) with obesity. Logistic regression and multivariable linear regression were applied to analyse the association between nutrient patterns in obesity and hyperuricemia. Mediation analyses were used to determine whether four obesity indicators, including body mass index (BMI), waist circumference (WC), visceral adiposity index (VAI) and lipid accumulation product index (LAP), mediated the relationship between nutrient patterns and hyperuricemia.

Results

PCA revealed three nutrient patterns (including “Low energy diet”, “Lower vitamin A, C, K pattern” and “Vitamin B group”), and only Vitamin B group had a total effect on hyperuricemia. RRR revealed one main nutrient pattern associated with obesity, which was characterized by High fat and low vitamin levels and was significantly associated with hyperuricemia. Mediation analysis showed that obesity mostly or even completely mediated the relationship between nutrient patterns and hyperuricemia, especially traditional obesity indicators, which played a key intermediary effect. The proportions of indirect effects for BMI and WC were as high as 53.34 and 59.69, respectively.

Conclusions

Our findings suggest that the direct effect of diet on hyperuricemia is weak, and obesity plays a critical mediating role in the relationship between diet and hyperuricemia, which confirms that a weight-loss diet such as a “Low fat and high vitamin diet” may be useful in preventing hyperuricemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14357-5.

Relation of BMI and waist circumference with the risk of new-onset hyperuricemia in hypertensive patients

BACKGROUND

We aimed to evaluate the relationship of body mass index (BMI) and waist circumference (WC) with the risk of new-onset hyperuricemia, and examine possible effect modifies in general hypertensive patients.

METHODS

A total of 10 611 hypertensive patients with normal uric acid (UA) concentrations (<357 μmol/l) at baseline were included from the UA sub-study of the China Stroke Primary Prevention Trial. The primary outcome was new-onset hyperuricemia, defined as a UA concentration ≥417 μmol/l in men or ≥357 μmol/l in women at the exit visit.

RESULTS

During a median follow-up duration of 4.4 years, 1663 (15.7%) participants developed new-onset hyperuricemia. When analyzed separately, increased BMI (≥25 kg/m2, quartile 3-4; OR, 1.46; 95% CI: 1.29-1.65), or increased WC (≥85 cm for females, quartile 3-4; OR, 1.24; 95% CI: 1.08-1.42; and ≥84 cm for males, quartile 3-4; OR, 1.30; 95% CI: 1.01-1.67) were each significantly associated with higher risk of new-onset hyperuricemia. When WC was forced into the model with BMI simultaneously, its significant association with new-onset hyperuricemia disappeared in females (<85 vs. ≥85 cm; OR, 0.96, 95% CI: 0.81-1.13) or males (≥84 vs. <84 cm; OR, 1.13; 95% CI: 0.84-1.52); however, BMI was still significantly related with new-onset hyperuricemia (≥25 vs. <25 kg/m2; OR, 1.48; 95% CI: 1.27-1.73). Moreover, the positive BMI & new-onset hyperuricemia association was more pronounced in participants with higher time-averaged on-treatment systolic blood pressure (median: <138.3 vs. ≥138.3 mmHg; P-interaction = 0.041).

CONCLUSIONS

Higher BMI, but not WC, is significantly and independently associated with an increased risk of new-onset hyperuricemia among hypertensive patients.

Association and mediation analyses among multiple metals exposure, plasma folate, and community-based impaired estimated glomerular filtration rate in central Taiwan

BACKGROUND

Chronic kidney disease (CKD) is increasing, with heavy metal exposure an important risk factor. Additionally, the antioxidant folic acid has been studied for reducing blood arsenic levels and related tissue damage. Therefore, we explored the association and mediation effects among various heavy metal levels in blood, plasma folate, other CKD risk factors, and impaired estimated glomerular filtration rate (eGFR).

METHODS

We constructed a community-based cross-sectional study from the Human Biomonitoring and Environmental Health Program in central Taiwan. A total of 1643 participants had lived locally for > 5 years, > 40 years old, and completely received health examinations and biospecimen collections. Impaired eGFR was defined as one single eGFR < 60 mL/min/1.73 m². Plasma folate and metal levels in blood were determined, as well as urinary 8-hydroxy-2'-deoxyguanosine as an oxidative stress marker. Generalized weighted quantile sum (WQS) regression analysis was used to calculate a WQS score, reflecting overall body-burden of multiple metals (arsenic, cadmium, chromium, nickel, and lead) in blood.

RESULTS

Impaired eGFR was identified in 225 participants. Participants with high WQS scores had increased risk of impaired eGFR (odds ratio = 1.67; 95% confidence interval [CI]: 1.34, 2.07). Of five metals, arsenic, lead, and cadmium were weighted highly in impaired eGFR. Participants with high WQS and folate insufficiency (< 6 ng/mL) had 2.38-fold risk of impaired eGFR compared to those with low WQS and high folate (≥6 ng/mL) (95% CI: 1.55, 5.17). Similar increased 4.16-fold risk of impaired eGFR was shown in participants with high WQS and uric acid levels (95% CI: 2.63, 6.58). However, there were no significant WQS-folate (p = 0.87) or WQS-uric acid (p = 0.38) interactions on impaired eGFR risk. As a mediator, uric acid contributed 24% of the association between WQS score and impaired eGFR risk (p < 0.0001). However, no mediation effect of plasma folate was observed.

CONCLUSION

WQS analysis could be applied to evaluate the joint effects of multiple metals exposure. High WQS scores may influence impaired eGFR risk through increased uric acid levels. A large-scale and prospective cohort study is necessary to validate these results and demonstrate any causal relationship.

Association of visceral adiposity index with new-onset type 2 diabetes and impaired fasting glucose in hypertensive Chinese adults

PURPOSE

Visceral adiposity index (VAI) is a reliable indicator for the distribution and function of adipose tissue in the body. The relation of VAI with new-onset type 2 diabetes and new-onset impaired fasting glucose (IFG) remains uncertain. We aimed to investigate the prospective relation of VAI with new-onset type 2 diabetes and new-onset IFG in Chinese hypertensive adults.

METHODS

A total of 14,838 hypertensive adults free of type 2 diabetes at baseline were included from the China Stroke Primary Prevention Trial. The primary outcome was new-onset type 2 diabetes, defined as physician-diagnosed diabetes or use of glucose-lowering drugs during follow-up, or fasting glucose ≥ 7.0 mmol/L at the exit visit. The secondary outcome was new-onset IFG, defined as fasting glucose < 6.1 mmol/L at baseline, while fasting glucose ≥ 6.1 mmol/L and < 7.0 mmol/L at the exit visit.

RESULTS

Over a median of 4.5 years' follow-up, 1612 (10.9%) participants developed type 2 diabetes. When VAI was categorized into quartiles, compared with participants in quartile 1-3 (< 2.80), significantly higher risk of new-onset type 2 diabetes (OR 1.30; 95% CI 1.08-1.56) and new-onset IFG (OR 1.28; 95% CI 1.08-1.52) was found in those in quartile 4 (≥ 2.80). Moreover, the positive associations were consistent in participants with or without single abnormal VAI components, including general obesity, abdominal obesity, elevated triglycerides and low high-density lipoprotein cholesterol (HDL-C) levels; or with different numbers of abnormal VAI components (all P interactions > 0.05).

CONCLUSION

Our study suggested a positive relation of VAI with the risk of new-onset type 2 diabetes and new-onset IFG in Chinese hypertensive patients, independent of its components.

LEVEL OF EVIDENCE

Level III, a well-designed cohort.

Interaction of Serum Alkaline Phosphatase and Folic Acid Treatment on Chronic Kidney Disease Progression in Treated Hypertensive Adults

The relation of alkaline phosphatase (ALP) with chronic kidney disease (CKD) is still uncertain. We aimed to examine the prospective association between serum ALP and CKD progression, and the modifying effect of serum ALP on folic acid in preventing CKD progression in treated hypertensive patients. This is a post-hoc analysis of 12,734 hypertensive adults with relevant measurements and without liver disease at baseline from the renal sub-study of the China Stroke Primary Prevention Trial, where participants were randomly assigned to daily treatments of 10 mg enalapril and 0.8 mg folic acid, or 10 mg enalapril alone. The primary outcome was CKD progression, defined as a decrease in estimated glomerular filtration rate (eGFR) of ≥30% and to a level of <60 ml/min/1.73 m² if baseline eGFR was ≥60 ml/min/1.73 m²; or a decrease in eGFR of ≥50% if baseline eGFR was <60 ml/min/1.73 m²; or end-stage renal disease. Over a median of 4.4 years, in the enalapril only group, participants with baseline serum ALP≥110IU/L (quartile 4) had a significantly higher risk of CKD progression (3.4% vs 2.3%; adjusted OR,1.61; 95%CI:1.11, 2.32), compared with those with ALP<110IU/L. For those with enalapril and folic acid treatment, compared with the enalapril only treatment, the risk of CKD progression was reduced from 3.4 to 2.1% (adjusted OR, 0.53; 95%CI:0.34, 0.83) among participants with baseline ALP≥110IU/L, whereas there was no significant effect among those with ALP<110IU/L. In hypertensive patients, higher serum ALP was associated with increased risk of CKD progression, and this risk was reduced by 47% with folic acid treatment.

Self-Perceived Psychological Stress and Risk of First Stroke in Treated Hypertensive Patients

OBJECTIVE

We aimed to investigate the prospective association between self-perceived psychological stress and first stroke, and to examine possible effect modifiers among adults with hypertension.

METHODS

A total of 20,688 hypertensive adults with information on self-perceived psychological stress at baseline were included from the China Stroke Primary Prevention Trial. Participants were randomly assigned to a double-blind treatment of receiving a single tablet daily with either 10 mg enalapril and 0.8 mg folic acid or 10 mg enalapril alone. Follow-up visits occurred every 3 months after randomization. Psychological stress was measured with a one-item 3-point rating scale. The primary outcome was first stroke (fatal or nonfatal).

RESULTS

The median treatment period was 4.5 years. Compared with participants with low levels of psychological stress, those with high psychological stress had a significantly higher risk of first stroke (adjusted hazard ratio = 1.40, 95% confidence interval = 1.01 to 1.94) or first ischemic stroke (adjusted hazard ratio = 1.45; 95% confidence interval = 1.01 to 2.09). Moreover, a stronger positive relationship between psychological stress and first stroke was found in participants with time-averaged mean arterial pressure <101 mm Hg (median; p-interaction = .004) during the treatment period. However, our study did not find a significant association between psychological stress and first hemorrhagic stroke.

CONCLUSIONS

Higher psychological stress was associated with an increased risk of first stroke among treated hypertensive patients, especially in those with lower mean arterial pressure during the treatment period.

Positive Association Between Serum Alkaline Phosphatase and First Stroke in Hypertensive Adults

The relation of alkaline phosphatase (ALP) with stroke risk remains uncertain. We aimed to examine the association between serum ALP and the risk of first stroke, and explore the possible effect modifiers in the association, among adults with hypertension. A total of 19,747 participants with baseline ALP measurements and without liver disease at baseline from the China Stroke Primary Prevention Trial (CSPPT) were included. The primary outcome was a first stroke. Over a median follow-up of 4.5 years, there was a positive association between serum ALP levels and the risk of first stroke (per SD increment, adjusted HR, 1.10; 95%CI: 1.01, 1.20). When serum ALP was evaluated as quartiles, a significantly higher risk of first stroke was observed in those in quartile 2–4 (ALP ≥79 IU/L; adjusted HR, 1.38; 95% CI: 1.11, 1.71), compared with participants in quartile 1 (ALP <79 IU/L). Similar results were found for first ischemic or hemorrhagic stroke. Similar findings were also found in those with a normal range of baseline ALP levels (20–140 IU/L) (per SD increment, adjusted HR, 1.15; 95%CI: 1.05, 1.27). None of the variables, including sex, age, body mass index, smoking, alcohol drinking, blood pressure, total cholesterol, fasting glucose levels at baseline, and blood pressure levels during the treatment period, significantly modified the association. In summary, our study suggests that higher serum ALP levels, even in normal range, were significantly related to higher risk of first stroke among Chinese hypertensive adults.

Plasma Vitamin E and the Risk of First Stroke in Hypertensive Patients: A Nested Case-Control Study

Background: The association between plasma vitamin E levels and first stroke risk in men and women remains unclear. Objective: We aimed to examine the prospective association between plasma vitamin E and first stroke, and evaluate the effect modifiers for the association, among hypertensive patients. Design: The study sample was drawn from the China Stroke Primary Prevention Trial (CSPPT), which randomized a total of 20,702 hypertensive patients to a double-blind, daily treatment with either 10 mg enalapril and 0.8 mg folic acid or 10 mg enalapril alone. This nested case-control study, including 618 first stroke cases and 618 controls matched for age, sex, treatment group, and study site, was conducted after the completion of the CSPPT. Results: The median follow-up duration was 4.5 years. Among men, a significantly higher risk of first stroke (adjusted OR, 1.67; 95%CI: 1.01, 2.77) was found for those with plasma vitamin E ≥7.1 μg/mL (≥quartile 1) compared with those with plasma vitamin E < 7.1 μg/mL. Subgroup analyses further showed that the association between vitamin E (≥7.1 vs. <7.1 μg/mL) and first stroke in men was significantly stronger in non-drinkers (adjusted OR, 2.64; 95%CI: 1.41, 4.96), compared to current drinkers (adjusted OR, 0.84; 95% CI: 0.43, 1.66, P-interaction = 0.008). However, there was no significant association between plasma vitamin E and first stroke in women (P-interaction between sex and plasma vitamin E = 0.048). Conclusions: Among Chinese hypertensive patients, there was a statistically significant positive association between baseline plasma vitamin E and the risk of first stroke in men, but not in women. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00794885, Identifier: NCT00794885.

Serum uric acid change in relation to antihypertensive therapy with the dihydropyridine calcium channel blockers

PURPOSE

We investigated serum uric acid changes in relation to the achieved clinic and ambulatory blood pressure after 8 weeks of antihypertensive therapy with two dihydropyridine calcium channel blockers.

MATERIALS AND METHODS

The study participants were patients with clinic and ambulatory hypertension, enrolled in a randomised controlled trial that compared amlodipine (5-10 mg, n = 215) and nifedipine gastrointestinal therapeutic system (GITS, 30-60 mg, n = 203). Hyperuricaemia was defined as a serum uric acid concentration of ≥420 µmol/L in men and ≥360 µmol/L in women. Analysis of covariance and multiple regression analyses were performed to study the associations between serum uric acid changes and the achieved clinic and ambulatory blood pressure during follow-up.

RESULTS

At baseline, 67 (16.0%) of the 418 patients had hyperuricaemia. Antihypertensive treatment reduced clinic and 24-h daytime and night-time systolic/diastolic blood pressure by a mean (±standard error [SE]) change of -17.4 ± 0.6/-8.6 ± 0.4 mm Hg and -13.7 ± 0.5/-8.3 ± 0.3 mm Hg, -13.8 ± 0.6/-8.4 ± 0.4 mm Hg, and -12.7 ± 0.7/-8.0 ± 0.4 mm Hg, respectively. Antihypertensive treatment reduced serum uric acid by a mean (±SE) change of -9.3 ± 2.8 μmol/L. The serum uric acid changes differed according to the achieved clinic and ambulatory blood pressure, and were statistically significant (mean ± SE -20.6 ± 6.6 to -10.7 ± 2.9 μmol/L, p ≤ 0.04) at the systolic/diastolic ranges of 130-139/≥90 mm Hg in clinic pressure, and <130/75-84 mm Hg, <145/80-84 mm Hg and <120/65-69 mm Hg in 24-h, daytime and night-time ambulatory pressure.

CONCLUSION

Our study showed that antihypertensive therapy with a dihydropyridine calcium channel blocker was associated with reduced serum uric acid, especially when 24-h ambulatory systolic blood pressure was controlled.

Urinary albumin-to-creatinine ratio and the risk of first stroke in Chinese hypertensive patients treated with angiotensin-converting enzyme inhibitors

We aimed to evaluate the relationship of the albumin-to-creatinine ratio (ACR) with the risk of first stroke and examine possible effect modifiers in hypertensive patients. A total of 11,632 hypertensive participants with urinary ACR measurements and without a history of stroke from the China Stroke Primary Prevention Trial (CSPPT) were included in this analysis. The primary outcome was first stroke. Over a median follow-up of 4.4 years, 728 first strokes were identified, of which 633 were ischemic, 89 were hemorrhagic, and 6 were uncertain types. Overall, there was a significant positive association between natural log-transformed ACR and the risk of first stroke (HR, 1.11; 95% CI: 1.03-1.20) and first ischemic stroke (HR, 1.12; 95% CI: 1.03-1.22). Consistently, participants with ACR ≥ 10 mg/g had a significantly higher risk of first stroke (HR, 1.26; 95% CI: 1.06-1.50) and first ischemic stroke (HR, 1.33; 95% CI: 1.10-1.59) than those with ACR < 10 mg/g. Moreover, the association of ACR with first stroke was significantly stronger in participants with higher total homocysteine (tHcy) levels (<10 versus ≥ 10 μmol/L; P for interaction = 0.044). However, there was no significant association between ACR and first hemorrhagic stroke (per natural log [ACR] increment: HR, 1.02; 95% CI: 0.82-1.27). In summary, hypertensive patients with ACR ≥ 10 mg/g had a significantly increased risk of first stroke or first ischemic stroke. This positive association was more pronounced among participants with higher tHcy levels.

Prospective association between baseline plasma zinc concentration and development of proteinuria in Chinese hypertensive patients

OBJECTIVE

We aimed to evaluate the association between baseline plasma zinc and the development of proteinuria as well as possible effect modifiers in hypertensive patients.

METHODS

This is a subset of the China Stroke Primary Prevention Trial (CSPPT) Renal Sub-Study. In the CSPPT, participants were randomized to receive a daily oral dose of 1 tablet containing 10 mg enalapril and 0.8 mg folic acid or 1 tablet containing 10 mg enalapril only. A total of 783 participants with plasma zinc measurements and without proteinuria at baseline were included in the current study. The study outcome was the development of proteinuria during the follow-up, defined as a urine dipstick reading of trace or ≥1+ at the exit visit.

RESULTS

During a median follow-up duration of 4.4 years, the development of proteinuria occurred in 93 (11.9 %) participants. There was an inverse relation of baseline plasma zinc with the development of proteinuria (per SD increment; OR, 0.74, 95 % CI: 0.55-0.99), p for trend of quartiles = 0.005.

CONCLUSIONS

In Chinese hypertensive patients, there was a significant inverse association between baseline plasma zinc and the development of proteinuria, although plasma zinc remained in the reference range.

Neutrophil counts and the risk of first stroke in general hypertensive adults

We aimed to investigate the association between neutrophil counts and first stroke and examine possible effect modifiers among treated hypertensive adults. This is a post hoc analysis of the China Stroke Primary Prevention Trial (CSPPT). A total of 11,878 hypertensive adults with data on neutrophil counts at baseline were included in the current study. The primary outcome was first stroke. During a median follow-up of 4.5 years, 414 (3.5%) participants experienced a first stroke, including 358 with ischemic stroke, 55 with hemorrhagic stroke and one with uncertain type of stroke. Compared with participants in quartile 1 (<2.9 × 10⁹/L) of neutrophil counts, those in the upper quartiles (quartile 2-4 [≥2.9 × 10⁹/L]) had a significantly higher risk of first stroke (HR, 1.35; 95% CI: 1.02, 1.78) or first ischemic stroke (HR, 1.38; 95% CI: 1.02, 1.86). Moreover, a strong positive association between neutrophil counts and first ischemic stroke was found in participants with total homocysteine (tHcy) levels <15 μmol/L (HR, 1.74; 95% CI: 1.17, 2.58; vs. ≥15 μmol/L; HR, 0.91; 95% CI: 0.57, 1.46, P interaction = 0.042) at baseline or time-averaged mean arterial pressure (MAP) ≥102 mmHg (median) (HR, 1.92; 95% CI: 1.27, 2.89; vs. <102 mmHg; HR, 0.89; 95% CI: 0.57, 1.41, P interaction = 0.015) during the treatment period. However, no such association between neutrophil counts and first hemorrhagic stroke was found. In summary, high baseline neutrophil counts were associated with an increased risk of first ischemic stroke among hypertensive patients, especially in those with low tHcy at baseline or high time-averaged MAP during the treatment period.

Degree of blood pressure control and the risk of new-onset hyperuricemia in treated hypertensive patients

Background

The relationship between blood pressure (BP) control and the risk of new-onset hyperuricemia remains uncertain. We aimed to examine the association between degree of time-averaged on-treatment BP control and new-onset hyperuricemia in general hypertensive patients.

Methods

A total of 10,617 hypertensive patients with normal uric acid (UA) concentrations (<357 µmol/L) at baseline were included from the UA Sub-study of the China Stroke Primary Prevention Trial (CSPPT). Participants were randomized to receive a double-blind daily treatment of enalapril 10 mg and folic acid 0.8 mg or enalapril 10 mg alone. BP measurements were taken every three months after randomization. The primary outcome was new-onset hyperuricemia, defined as a UA concentration ≥417 µmol/L in men or ≥357 µmol/L in women at the exit visit.

Results

Over a median of 4.4 years, 1,664 (15.7%) participants developed new-onset hyperuricemia. Overall, there was a significantly positive association between time-averaged on-treatment diastolic BP (DBP) and new-onset hyperuricemia (per 10 mmHg increment; OR 1.13; 95% CI: 1.02–1.26). Consistently, a significantly higher risk of new-onset hyperuricemia was found in participants with time-averaged on-treatment DBP ≥82.9 mmHg (median) (vs. <82.9 mmHg; 17.3% vs. 14.1%; OR 1.25; 95% CI: 1.10–1.44). Furthermore, the lowest new-onset hyperuricemia risk (12.1%) was found in those with both time-averaged on-treatment SBP (median: 138.3 mmHg) and DBP below the median (P-interaction=0.023). The results were similar for time-averaged DBP during the first 12- or 24-month treatment period, or in the analysis using propensity scores. Furthermore, a non-significant higher risk of new-onset hyperuricemia was observed in participants with time-averaged on-treatment SBP ≥120 mmHg (vs. <120 mmHg; OR 1.61; 95% CI: 0.88–2.97).

Conclusions

A tight DBP control of <82.9 mmHg was associated with lower risk of new-onset hyperuricemia among hypertensive patients without hyperuricemia.

Plasma 25-Hydroxyvitamin D3 Concentrations and Risk of New-Onset Proteinuria in Patients With Hypertension

OBJECTIVE

We aimed to evaluate the relationship of plasma 25-hydroxyvitamin D3 (25[OH]D3) with the risk of new-onset proteinuria and examine the possible effect modifiers in patients with hypertension and without chronic kidney disease at baseline.

METHODS

This is a post hoc analysis of the renal substudy of the China Stroke Primary Prevention Trial. A total of 1655 patients with hypertension, who had plasma 25(OH)D3 measurements, as well as without proteinuria and with an estimated glomerular filtration rate of ≥60 mL/min/1.73 m² at baseline, were included in the present study. The main outcome was new-onset proteinuria, defined as a urine dipstick reading of ≥1+ at the exit visit.

RESULTS

The mean (standard deviation) 25(OH)D3 level at baseline was 18.6 (7.5) ng/mL. The median follow-up duration was 4.4 years. Overall, there was a significant inverse association between plasma 25(OH)D3 and the risk of new-onset proteinuria (per standard deviation increment; [odds ratio] OR: 0.70; 95% confidence interval [CI]: 0.50, 0.97). Accordingly, when 25(OH)D3 was assessed as quartiles, a significantly lower risk of new-onset proteinuria was found in participants in quartiles 3-4 (≥17.8 ng/mL; OR: 0.45; 95% CI: 0.23, 0.87), compared with those in quartile 1 (<13.1 ng/mL). Furthermore, a stronger inverse relationship of plasma 25(OH)D3 and new-onset proteinuria was observed in nondiabetic participants (per standard deviation increment; OR: 0.57; 95% CI: 0.39, 0.83; vs. diabetics: OR: 1.48; 95% CI: 0.67, 3.28; P for interaction = 0.028).

CONCLUSION

There was a significant inverse association between plasma 25(OH)D3 and the risk of proteinuria in patients with hypertension, especially in those without diabetes.

Interaction of neutrophil counts and folic acid treatment on new-onset proteinuria in hypertensive patients

We aimed to examine whether baseline neutrophil counts affected the risk of new-onset proteinuria in hypertensive patients, and, if so, whether folic acid treatment is particularly effective in proteinuria prevention in such a setting. A total of 8208 eligible participants without proteinuria at baseline were analysed from the renal substudy of the China Stroke Primary Prevention Trial. Participants were randomised to receive a double-blind daily treatment of 10 mg of enalapril and 0·8 mg of folic acid (n 4101) or 10 mg of enalapril only (n 4107). The primary outcome was new-onset proteinuria, defined as a urine dipstick reading of ≥1+ at the exit visit. The mean age of the participants was 59·5 (sd, 7·4) years, 3088 (37·6 %) of the participants were male. The median treatment duration was 4·4 years. In the enalapril-only group, a significantly higher risk of new-onset proteinuria was found among participants with higher neutrophil counts (quintile 5; ≥4·8 × 109/l, OR 1·44; 95 % CI 1·00, 2·06), compared with those in quintiles 1–4. For those with enalapril and folic acid treatment, compared with the enalapril-only group, the new-onset proteinuria risk was reduced from 5·2 to 2·8 % (OR 0·49; 95 % CI 0·29, 0·82) among participants with higher neutrophil counts (≥4·8 × 109/l), whereas there was no significant effect among those with neutrophil counts <4·8 × 109/l. In summary, among hypertensive patients, those with higher neutrophil counts had increased risk of new-onset proteinuria, and this risk was reduced by 51 % with folic acid treatment.

Serum alkaline phosphatase levels and the risk of new-onset diabetes in hypertensive adults

BACKGROUND

The association between alkaline phosphatase (ALP) and incident diabetes remains uncertain. Our study aimed to investigate the prospective relation of serum ALP with the risk of new-onset diabetes, and explore possible effect modifiers, in hypertensive adults.

METHODS

A total 14,393 hypertensive patients with available ALP measurements and without diabetes and liver disease at baseline were included from the China Stroke Primary Prevention Trial (CSPPT). The primary outcome was new-onset diabetes, defined as physician-diagnosed diabetes or use of glucose-lowering drugs during follow-up, or fasting glucose ≥ 7.0 mmol/L at the exit visit. The secondary study outcome was new-onset impaired fasting glucose (IFG), defined as FG < 6.1 mmol/L at baseline and ≥ 6.1 but < 7.0 mmol/L at the exit visit.

RESULTS

Over a median of 4.5 years follow-up, 1549 (10.8%) participants developed diabetes. Overall, there was a positive relation of serum ALP and the risk of new-onset diabetes (per SD increment, adjusted OR, 1.07; 95% CI: 1.01, 1.14) and new-onset IFG (per SD increment, adjusted OR, 1.07; 95% CI: 1.02, 1.14). Moreover, a stronger positive association between baseline ALP (per SD increment) with new-onset diabetes was found in participants with total homocysteine (tHcy) < 10 μmol/L (adjusted OR, 1.24; 95% CI: 1.10, 1.40 vs. ≥ 10 μmol/L: adjusted OR, 1.03; 95% CI: 0.96, 1.10; P-interaction = 0.007) or FG ≥ 5.9 mmol/L (adjusted OR, 1.16; 95% CI: 1.07, 1.27 vs. < 5.9 mmol/L: adjusted OR, 1.00; 95% CI: 0.93, 1.08; P-interaction = 0.009) CONCLUSIONS: In this non-diabetic, hypertensive population, higher serum ALP was significantly associated with the increased risk of new-onset diabetes, especially in those with lower tHcy or higher FG levels. Clinical Trial Registration-URL Trial registration: NCT00794885 (clinicaltrials.gov). Retrospectively registered November 20, 2008.

Association of self-reported sleep duration and quality with BaPWV levels in hypertensive patients

The association between sleep conditions and arterial stiffness remains inconclusive. We aimed to investigate the relationship of sleep duration and quality with brachial-ankle pulse-wave velocity (baPWV) in hypertensive patients. A total of 14,485 hypertensive adults were included in this cross-sectional analysis. Information about sleep duration and quality was obtained via questionnaire. A baPWV level ≥1800 cm/s was defined as indicative of arterial stiffness. Compared with participants with a sleep duration <8 h per day, participants with a sleep duration ≥8 h per day had a significantly higher baPWV level (β = 13.7 cm/s; 95% CI: 3.9, 23.5) and a nonsignificantly higher prevalence of arterial stiffness (39.7% vs. 33.0%; OR, 1.08; 95% CI: 0.99-1.19). Similarly, compared with participants with good or medium sleep quality, participants with poor sleep quality had a significantly higher baPWV level (β = 16.3 cm/s; 95% CI: 0.1, 32.6) and a nonsignificantly greater prevalence of arterial stiffness (36.6% vs. 35.3%; OR, 1.13; 95% CI: 0.97-1.32). When sleep duration and quality were examined jointly, participants with a sleep duration ≥8 h and/or poor sleep quality had a significantly higher baPWV level (β = 14.4 cm/s; 95% CI: 5.3, 23.4) and a greater prevalence of arterial stiffness (38.8% vs. 32.7%; OR, 1.10; 95% CI: 1.01-1.20) than those with a sleep duration <8 h and good/medium sleep quality. In summary, among hypertensive patients, a longer sleep duration (≥8 h per day) and poor sleep quality were associated with higher baPWV levels and a higher prevalence of arterial stiffness.

Baseline Serum Bilirubin and Risk of First Stroke in Hypertensive Patients

Background

Data on the association between serum bilirubin and the risk of stroke are limited and inconclusive. We aimed to evaluate the association between serum bilirubin and the risk of first stroke and to examine any possible effect modifiers in hypertensive patients.

Methods and Results

Our study was a post hoc analysis of the CSPPT (China Stroke Primary Prevention Trial). A total of 19 906 hypertensive patients were included in the final analysis. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% CIs for the risk of first stroke associated with serum bilirubin levels. The median follow‐up period was 4.5 years. When serum total bilirubin was assessed as tertiles, the adjusted HR of first ischemic stroke for participants in tertile 3 (12.9–34.1 μmol/L) was 0.75 (95% CI, 0.59–0.96), compared with participants in tertile 1 (<9.3 μmol/L). When direct bilirubin was assessed as tertiles, a significantly lower risk of first ischemic stroke was also found in participants in tertile 3 (2.5–24.8 μmol/L) (adjusted HR, 0.77; 95% CI, 0.60–0.98), compared with those in tertile 1 (<1.6 μmol/L). However, there was no significant association between serum total bilirubin (tertile 3 versus 1: adjusted HR, 1.45; 95% CI, 0.89–2.35) or direct bilirubin (tertile 3 versus 1: adjusted HR, 1.27; 95% CI, 0.76–2.11) and first hemorrhagic stroke.

Conclusions

In this sample of Chinese hypertensive patients, there was a significant inverse association between serum total bilirubin or direct bilirubin and the risk of first ischemic stroke.

Safety, efficacy and tolerability of a combination micronutrient and polyherbal preparation (GoutFighter TM) for gout: a single-arm open-label pilot study

BACKGROUND

To evaluate the safety, efficacy and tolerability of a combination micronutrient and polyherbal preparation (GoutFighter ^TM) for gout management.

METHODS

A single arm, open-label pilot study was conducted at the National Hospital for Traditional Medicine in Vietnam. Participants (n=35 recruited) diagnosed with chronic gout received four tablets of GoutFighter ^TM daily over a 45-day period. Efficacy was assessed by changes in pain, swelling and blood uric acid levels, with concurrent safety and tolerability assessments.

RESULTS

A total of 27 (85.2% male) participants (mean ± SD age, 54.2 ± 12.5 years; BMI, 24.2 ± 3.6 kg/m²) with gout (median [IQR], years since diagnosis 4.0 [3.0-8.0]) completed intervention. In relation to safety, there were no significant changes in vital signs, blood biochemistry or cell counts. In regard to efficacy, the degree of perceived pain and frequency of joint swelling significantly declined after 15 and 30 days of treatment, respectively, and remained so until the end of trial. Mean blood uric acid levels also declined by 25.8 μmol/L (95% CI, 3.7 to 48.0, p=0.024). Overall, the predominance of participants (96.3%) responded favorably to treatment (p<0.0001) and GoutFighter ^TM was well tolerated, with no serious adverse events.

CONCLUSION

Clinically relevant doses of GoutFighter ^TM were found to be generally safe, well-tolerated and effective for the short-term, symptomatic relief of chronic gout. GoutFighter ^TM appears to be suitable as an adjunctive treatment in lifestyle programs for gout management, and further investigation in placebo-controlled trials is therefore warranted.

Serum homocysteine levels and their association with clinical characteristics of inflammatory arthritis

OBJECTIVE

The aim of our study was to explore the serum levels of homocysteine (Hcy) and its association with clinical characteristics in patients with different types of inflammatory arthritis.

METHODS

A total of 242 patients diagnosed with inflammatory arthritis (which included rheumatoid arthritis (RA), ankylosing spondylitis (AS), and gout), 49 with osteoarthritis (OA), and 36 with hyperuricaemia (HUA) and 81 healthy controls (HCs) were enrolled for comparisons.

RESULTS

The serum Hcy levels of patients with RA, AS, and OA were comparable with those of the HC group (P > 0.05). However, the serum level of Hcy was significantly higher in patients with gout than in HCs (18.75 ± 9.98 vs. 14.20 ± 6.22 μmol/L, P = 0.007). In addition, we found that the serum Hcy level was much higher in RA patients who received methotrexate (MTX) therapy without folic acid supplementation than in those who received MTX with folic acid supplementation (13.39 ± 4.80 vs. 9.41 ± 2.04 μmol/L, P = 0.001). Furthermore, there was a positive correlation between uric acid and Hcy in patients without uric acid-lowering treatment (r = 0.537, P = 0.002), but the correlation was eliminated after adjusting uric acid-lowering treatment (r = 0.139, P = 0.393). Finally, consistent with the above findings, hyperhomocysteinaemia (HHcy) was more common in gout patients (P < 0.05).

CONCLUSION

Screening for HHcy in patients with gout and RA, especially RA patients treated with MTX, might be necessary, and patients with HHcy might benefit from earlier supplementation with folic acid. Key Points • Serum homocysteine (Hcy) was elevated and the rate of hyperhomocysteinaemia (HHcy) was significantly higher in gout. • Rheumatoid arthritis (RA) patients who received methotrexate (MTX) treatment without folic acid supplementation showed higher serum Hcy than those who received MTX treatment with folic acid supplementation. • The serum Hcy level was positively correlated with age in only RA patients. • Serum Hcy was correlated with uric acid in gout patients, but the correlation was eliminated after adjusting uric acid-lowering treatment.

Plasma magnesium and the risk of new-onset hyperuricaemia in hypertensive patients

We aimed to evaluate the relationship of plasma Mg with the risk of new-onset hyperuricaemia and examine any possible effect modifiers in hypertensive patients. This is a post hoc analysis of the Uric acid (UA) Sub-study of the China Stroke Primary Prevention Trial (CSPPT). A total of 1685 participants were included in the present study. The main outcome was new-onset hyperuricaemia defined as a UA concentration ≥417 μmol/l in men or ≥357 μmol/l in women. The secondary outcome was a change in UA concentration defined as UA at the exit visit minus that at baseline. During a median follow-up duration of 4·3 years, new-onset hyperuricaemia occurred in 290 (17·2 %) participants. There was a significantly inverse relation of plasma Mg with the risk of new-onset hyperuricaemia (per sd increment; OR 0·85; 95 % CI 0·74, 0·99) and change in UA levels (per sd increment; β -3·96 μmol/l; 95 % CI -7·14, -0·79). Consistently, when plasma Mg was analysed as tertiles, a significantly lower risk of new-onset hyperuricaemia (OR 0·67; 95 % CI 0·48, 0·95) and less increase in UA levels (β -8·35 μmol/l; 95 % CI -16·12, -0·58) were found among participants in tertile 3 (≥885·5 μmol/l) compared with those in tertile 1 (<818·9 μmol/l). Similar trends were found in males and females. Higher plasma Mg levels were associated with a decreased risk of new-onset hyperuricaemia in hypertensive adults.

Association of plasma retinol levels with incident cancer risk in Chinese hypertensive adults: a nested case-control study

We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults. We conducted a nested case-control study, including 231 patients with incident cancer and 231 matched controls during a median 4·5-year follow-up of the China Stroke Primary Prevention Trial. There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dl increases: OR 0·79; 95 % CI 0·69, 0·91). When compared with participants in the first quartile of retinol (< 52·3 μg/dl), a significantly lower cancer risk was found in participants in quartile 2-4 ( ≥ 52·3 μg/dl: OR 0·31; 95 % CI 0·13, 0·71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dl increases: OR 0·89; 95 % CI 0·60, 1·31) in participants with retinol < 68·2 μg/dl, and then increased significantly with retinol (per 10 μg/dl increase: OR 1·65; 95 % CI 1·12, 2·44) in participants with retinol ≥ 68·2 μg/dl. In conclusion, there was a significant inverse dose-response association between plasma retinol and the risk of digestive system cancers. However, a U-shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point approximately 68·2 μg/dl).

Folate, Vitamin B6 and Vitamin B12 Intake in Relation to Hyperuricemia

To assess the association between intake of folate, vitamin B6, and vitamin B12 with hyperuricemia (HU) among adults from the United States (US), we extracted relevant data from 24,975 US adults aged 20–85 years from the National Health and Nutrition Examination Survey (NHANES) in 2001–2014. All dietary intake was evaluated by 24-h dietary recalls. Multivariable logistic regression analysis was performed to explore the associations after adjustment for confounders. Compared to the lowest quintile (Q1), for males, adjusted odds ratios (ORs) of HU in Q2 to Q5 of folate (dietary folate equivalent, DFE) intake were 0.84 (95% CI, 0.73–0.96), 0.84 (0.73–0.97), 0.72 (0.62–0.84), and 0.64 (0.53–0.77), respectively (p for trend <0.0001). In females, adjusted ORs in Q2 to Q4 of folate (DFE) intake were 0.84 (95% CI, 0.71–0.99), 0.81 (0.68–0.96), and 0.82 (0.68–0.99), with a p for trend of 0.1475. Our findings indicated the intakes of total folate, folic acid, food folate, folate (DFE), vitamin B12, but not vitamin B6, were inversely related to the risk of HU in males. A lower risk of HU with higher intakes of total folate, food folate, and folate (DFE) was found in females, but with no association between intakes of folic acid, vitamin B6, B12, and the risk of HU for females.

Asymptomatic hyperuricemia: is it time to intervene?

Whether to treat hyperuricemia uncomplicated by articular gout, urolithiasis, or uric acid nephropathy is an exercise in clinical judgment and universal agreement is lacking. Patients with coronary artery disease, chronic kidney disease, and early onset hypertension with persistent hyperuricemia are likely to be benefited with urate-lowering therapy. The paradigm of the causative association of hyperuricemia with cardiovascular and chronic kidney diseases seems to have progressed from skepticism to increasing evidence of a true relationship. Although such evidences are mounting, they are not enough to support pharmacotherapy for all patients with asymptomatic hyperuricemia. Further studies are needed to determine which patients are likely to get beneficial effects from pharmacotherapy and the minimum threshold of uric acid level required to experience clinical benefits.