Effect of changes in serum uric acid on the risk of stroke and its subtypes

Lifestyle risk factors and stroke: findings from the national health and nutrition examination survey (1999-2020) and a Mendelian randomization analysis

OBJECTIVES

This study aimed to assess the relationship between lifestyle risk factors and stroke, as well as to quantify causality, using data from the National Health and Nutrition Examination Survey (NHANES) and Mendelian randomization (MR).

METHODS

We analyzed data from 28,226 individuals who participated in NHANES between 1999 and 2020. To evaluate the association between lifestyle risk factors and stroke, we used weighted multivariate logistic regression. Genome-wide association study (GWAS) summary data were utilized to conduct bidirectional two-sample MR and multivariate MR analyses.

RESULTS

The NHANES observational study found that waist circumference, smoking, and creatinine were consistently and positively associated with stroke in multivariable-adjusted models, with odds ratios (OR) of 1.010 (95% confidence interval [CI], 1.001-1.019, p = 0.046), 1.653 (95% CI, 1.310-2.084, p < 0.001), and 1.400 (95% CI, 1.183-1.657, p < 0.001), respectively. Conversely, engaging in vigorous physical activities was a protective factor against stroke, with an OR of 0.572 (95% CI, 0.342-0.961, p = 0.037). Bidirectional two-sample and multivariate MR analyses revealed a causal link between smoking, waist circumference, and stroke (OR = 1.237, 95% CI, 1.130-1.354; OR = 1.239, 95% CI, 1.149-1.335, respectively).

DISCUSSION

Vigorous activities, especially fitness and recreational activities, serve as a protective factor against stroke. Smoking and increased waist circumference represent consistent lifestyle-related risk factors for stroke.

Association between serum urate levels and all-cause mortality, cardiovascular and renal outcomes among gout patients in Singapore

OBJECTIVES

We investigated the longitudinal association between Serum Urate (SU) level and Acute Myocardial Infarction (AMI), Stroke, End Stage Renal Failure (ESRF) and all-cause mortality.

DESIGN

We conducted a retrospective hospital-based cohort study of individuals with gout managed in specialist outpatient clinics. Cox proportional hazards regression was used to estimate HR and 95% CI, with adjustments for potential confounders. Where the proportional hazard assumption was violated, stratified Cox regression was applied instead.

SETTING

An acute care tertiary hospital in Singapore.

PARTICIPANTS

Individuals with a first gout diagnosis between 2007-2017, identified through (i) primary discharge diagnosis, (ii) diagnosis from the Rheumatology SOC (iii) patient history of a clinical encounter at the Rheumatology SOC plus use of urate-lowering therapy/colchicine.

MAIN OUTCOME MEASURES

All-cause mortality, AMI, Stroke and ESRF ascertained through data linkage with the National Registry of Diseases Office.

RESULTS

The final cohort comprised 2,866 individuals. Post follow-up, there were 800 deaths and 362, 218 and 191 occurrences of AMI, ESRF and stroke respectively. Compared to the reference (second-lowest) SU quartile, being in the highest SU quartile was associated with a significantly increased hazard for mortality (HR:1.66, 95% CI:1.36-2.03), incident ESRF (HR:3.02, 95% CI:2.00-4.56), and increased hazard for incident AMI (HR:1.42, 95% CI:1.06-1.91). The p-trend for all 3 outcomes was significant. No significant association was found between SU quartile and hazard for incident stroke.

CONCLUSIONS

This study found that individuals with gout managed at SOC who had higher baseline SU levels had an increased hazard for all-cause mortality, ESRF, and AMI.

CLINICAL TRIAL NUMBER

Not applicable.

Serum Uric Acid Levels Associated with Outcomes of Neurodegenerative Disorders and Brain Health: Findings from the UK Biobank

BACKGROUND

The relationship between serum uric acid (SUA) levels and brain-related health remains uncertain.

OBJECTIVES

This study aimed to investigate the relationship between SUA levels and some neurodegenerative disorders and brain structure.

DESIGN

A longitudinal study.

SETTING AND PARTICIPANTS

384,517 participants who did not have stroke, dementia, and Parkinsonism, with complete urate testes and covariates were included.

MEASUREMENTS

Cox proportional hazards models, competing risk models, and restricted cubic spine models were applied.

RESULTS

During the median follow-up time of 12.7 years (interquartile range [IQR]:12.0, 13.5), 7821 (2.0%) participants developed stroke, 5103 (1.3%) participants developed dementia, and 2341 (0.6%) participants developed Parkinsonism. Nonlinear relationships were identified between SUA levels and stroke (J-shaped), dementia, and Parkinsonism (U-shaped). SUA levels of 4.2 mg/dl, 6.4 mg/dl, and 6.6 mg/dl yielded the lowest risk of stroke, dementia, and Parkinsonism, respectively. Besides, we found high SUA levels reduced the volumes of total brain, grey matter, white matter, grey matter in the hippocampus, and hippocampus, but increased lateral-ventricle volume. Inflammation accounted for 9.1% and 10.0% in the association of SUA with stroke and lateral-ventricle volume.

CONCLUSIONS

Lower SUA levels increased the risk of Parkinsonism, while both lower and higher SUA levels were positively associated with increased risk of stroke and dementia. Moreover, high SUA levels reduced brain structure volumes. Our findings suggest the association between SUA levels and brain-related disorders and highlight the importance of SUA management.

Dual effects of serum urate on stroke risk and prognosis: insights from Mendelian randomization

Background

To investigate the causal associations of serum urate (SUA) with stroke risk and prognosis using Mendelian randomization (MR) and the potential mediating role of stroke risk factors in the causal pathways.

Methods

We used the random-effects inverse variance weighting (IVW) as our primary method. We initially performed two-sample univariable MR (UVMR) to identify the causal associations of SUA (n = 437,354) with any stroke (AS, FinnGen: n = 311,635; MEGASTROKE: n = 446,696), ischemic stroke (IS, FinnGen: n = 212,774; MEGASTROKE: n = 440,328), intracranial hemorrhage (ICH, FinnGen: n = 343,663; ISGC: n = 3,026), functional outcome after ischemic stroke at 90d (n = 4,363), and motor recovery within 24 months after stroke (n = 488), and then multivariable MR (MVMR) to estimate the direct causal effects of SUA on these outcomes, adjusting for potential confounders. Finally, we further conducted a two-step MR to investigate the potential mediating role of body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), and estimated glomerular filtration rate (eGFR) in the identified causal pathways.

Results

Genetically predicted elevated SUA levels were significantly associated with increased risk of AS (meta-analysis: OR = 1.09, 95% CI [1.04-1.13], p = 3.69e-05) and IS (meta-analysis: OR = 1.10, 95% CI [1.01-1.19], p = 0.021) and with improved poor functional outcome after ischemic stroke at 90d (OR = 0.81, 95% CI [0.72-0.90], p = 1.79e-04) and motor recovery within 24 months after stroke (OR = 1.42, 95% CI [1.23-1.64], p = 2.15e-06). In MVMR, SBP and DBP significantly attenuated the causal effects of SUA on AS, IS, and functional outcome after ischemic stroke at 90d and motor recovery within 24 months after stroke. Further mediation analyses showed that SBP mediated 52.4 and 34.5% of the effects of SUA on AS and IS, while DBP mediated 28.5 and 23.4% of the causal effects, respectively.

Conclusion

This study supports the dual role of genetically predicted SUA in increasing stroke risk, especially ischemic stroke risk, and in improving functional outcome and motor recovery. SBP and DBP are key mediators lying on the causal pathways of SUA with AS and IS.

Scientific Landscape of Oxidative Stress in Stroke: From a Bibliometric Analysis to an in-Depth Review

Stroke is an acute cerebrovascular disease resulting from either obstruction or rupture of a blood vessel in the brain. Oxidative stress (OS), referred to a status where cellular oxidative capacities overwhelm antioxidative defenses, is involved in the pathophysiology of stroke. The bibliometric analysis and in-depth review aim to depict the research trend of OS in stroke. Relevant scientific publications were acquired from the Web of Science Core Collection database. Scientific landscape of OS in stroke was illustrated by general quantitative trend, impactful journals, and co-authorship of various academic units (i.e., countries/regions, organizations, and authors). Furthermore, theme analysis predicting the hot research issues and frontiers was performed. 15,826 documents regarding OS in stroke were obtained over a time span of more than 20 years from 1992 to 2021. The overall tendency of publication counts was continuously on the rise. Bibliometric analysis indicated China and the United States were predominant in this study field, as reflected by their high publication counts and intensive collaboration with other countries. Current key research areas of OS in stroke may lie in the investigation of neuroinflammation, and interaction among multiple cell death mechanisms including apoptosis, autophagy, and ferroptosis to search for effective treatments. Moreover, another hot topic could be the association between air pollution and stroke, and its underlying mechanisms. As the exploration of OS in stroke is speculated to be a continuous hot spot in the future, this article may be helpful for researchers to conduct future studies with the understanding of influential academic forces and research highlights.

Moderate elevation of serum uric acid levels improves short-term functional outcomes of ischemic stroke in patients with type 2 diabetes mellitus

BACKGROUND

Serum uric acid (SUA), an end-product of purine catabolism diffused in the blood, is positively associated with the risk of type 2 diabetes mellitus (T2DM). However, in the T2DM population, the association of SUA fluctuation ([Formula: see text]SUA) with the functional outcome of ischemic stroke (IS) is still unclear. Accordingly, this study aimed to assess the correlation between [Formula: see text]SUA and short-term IS functional outcomes in T2DM patients.

METHODS

All T2DM patients diagnosed with IS in the China National Stroke Registry III were included. [Formula: see text]SUA, which was defined as the difference between the SUA levels at baseline and 3 months after symptom onset, was classified into two groups, i.e., elevated [Formula: see text]SUA ([Formula: see text]SUA > 0) and reduced [Formula: see text]SUA ([Formula: see text]SUA [Formula: see text] 0). The outcomes measured using the Modified Rankin Scale (mRS) were scored from 0 to 6, and poor functional outcome was defined as an mRS score of 3-6 at 3 months after IS.

RESULTS

Among the 1255 participants (mean age: 61.6 ± 9.8 years), 64.9% were men. Patients with elevated [Formula: see text]SUA had a lower incidence of poor functional outcomes at 3 months. Compared with reduced [Formula: see text]SUA, elevated [Formula: see text]SUA at 0-50 μmol/L (odds ratio [OR] = 0.46, 95% confidence interval [CI] = 0.28-0.78, p = 0.004) and 50-100 μmol/L (OR = 0.40, 95% CI = 0.21-0.77, p = 0.006) was significantly correlated with a reduced risk of poor functional outcomes at 3 months.

CONCLUSION

This study showed that a moderate increase in [Formula: see text]SUA in the range of 0-100 μmol/L at 3 months after IS might be beneficial in T2DM adults and more studies are warranted to confirm this.

Association of hyperuricemia with cardiovascular diseases: current evidence

The aim of the present study is to present a historical and unified perspective on the association of serum uric acid (SUA) in the cause of cardiovascular diseases (CVDs). The association of hyperuricemia (HUC) with CVD begun to be appreciated in the middle 1950s and early 1990s when clinical evidence was shown on the association of HUC with CVD. However, this association was disputed by several investigators including the Framingham group and by professional societies, like the American Heart Association and the American Society of Hypertension. This dispute was weakened or reversed by later studies, which showed a positive association of HUC with CVD, CHD, HF, CKD, and stroke, mediated by several risk factors, both molecular such as, oxidative stress, inflammatory stress, insulin resistance, and endothelial dysfunction, as well as clinical factors such as, atherosclerosis, hypertension, metabolic syndrome, and type 2 diabetes mellitus. The great majority of recent studies show a positive association of HUC with CVDs, and CKD. However, the cutoff of the damaging levels of SUA have not been established as yet. The European Society of Hypertension (ESH) Treatment Guidelines have proposed a cutoff level of SUA for CVD > 7 mg/dl for men and > 6 mg/dl for women. In contrast, the URRAH study has shown a SUA level of 4.7 mg/dl for all-cause mortality and 5.6 mg/dl for CV mortality. These levels are lower than the SUA levels proposed by the ESH, which are consistent with HUC. For a better understanding of this association, a Medline search of the English literature was conducted between 2015 and 2022 and 44 pertinent papers were selected. These papers together with collateral literature will be discussed in this review.