Biological Age Acceleration Is Lower in Women With Ischemic Stroke Compared to Men

Gender Predicts Differences in Acute Ischemic Cardioembolic Stroke Profile: Emphasis on Woman-Specific Clinical Data and Early Outcome-The Experience of Sagrat Cor Hospital of Barcelona Stroke Registry

Background and Objectives: Acute ischemic cardioembolic stroke (CS) is a clinical condition with a high risk of death, and can lead to dependence, recurrence, and dementia. Materials and Methods: In this study, we evaluated gender differences and female-specific clinical data and early outcomes in 602 women diagnosed with CS from a total of 4600 consecutive acute stroke patients in a single-center hospital stroke registry over 24 years. A comparative analysis was performed in women and men in terms of demographics, cerebrovascular risk factors, clinical data, and early outcomes. Results: In a multivariate analysis, age, hypertension, valvular heart disease, obesity, and internal capsule location were independent variables associated with CS in women. The overall in-hospital mortality rate was similar, but the group of women had a greater presence of neurological deficits and a higher percentage of severe limitation at hospital discharge. After the multivariate analysis, age, altered consciousness, limb weakness, and neurological, respiratory, gastrointestinal, renal, cardiac and peripheral vascular complications were independent predictors related to early mortality in women. Conclusions: Women with CS showed a differential demographic and clinical profile and worse early outcomes than men. Advanced age, impaired consciousness, and medical complications were predictors of stroke severity in women with CS.

Sex differences in frailty among older adults

By definition, aging is a natural, gradual and continuous process. On the other hand, frailty reflects the increase in vulnerability to stressors and shortens the time without disease (health span) while longevity refers to the length of life (lifespan). The average life expectancy has significantly increased during the last few decades. A longer lifespan has been accompanied by an increase in frailty and decreased independence in older adults, with major differences existing between men and women. For example, women tend to live longer than men but also experience higher rates of frailty and disability. Sex differences prevent optimization of lifestyle interventions and therapies to effectively prevent frailty. Sex differences in frailty and aging are rooted in a complex interplay between uncontrollable (genetic, epigenetic, physiological), and controllable factors (psychosocial and lifestyle factors). Thus, understanding the underlying causes of sex differences in frailty and aging is essential for developing personalized interventions to promote healthy aging and improve quality of life in older men and women. In this review, we have discussed the key contributors and knowledge gaps related to sex differences in aging and frailty.

Ischaemic stroke patients present sex differences in gut microbiota

BACKGROUND

Gut microbiota plays a role in the pathophysiology of ischaemic stroke (IS) through the bidirectional gut-brain axis. Nevertheless, little is known about sex-specific microbiota signatures in IS occurrence.

METHODS

A total of 89 IS patients and 12 healthy controls were enrolled. We studied the taxonomic differences of the gut microbiota between men and women with IS by shotgun metagenomic sequencing. To evaluate the causal effect of several bacteria on IS risk, we performed a two-sample Mendelian randomisation (MR) with inverse-variance weighting (IVW) using genome-wide association analysis (GWAS) summary statistics from two cohorts of 5959 subjects with genetic and microbiota data and 1,296,908 subjects with genetic and IS data, respectively.

RESULTS

α-Diversity analysis measured using Observed Species (p = 0.017), Chao1 (p = 0.009) and Abundance-based Coverage Estimator (p = 0.012) indexes revealed that IS men have a higher species richness compared with IS women. Moreover, we found sex-differences in IS patients in relation to the phylum Fusobacteria, class Fusobacteriia, order Fusobacteriales and family Fusobacteriaceae (all Bonferroni-corrected p < 0.001). MR confirmed that increased Fusobacteriaceae levels in the gut are causally associated with an increased risk of IS (IVW p = 0.02, β = 0.32).

CONCLUSIONS

Our study is the first to indicate that there are gut microbiome differences between men and women with IS, identifying high levels of Fusobacteriaceae in women as a specific risk factor for IS. Incorporating sex stratification analysis is important in the design, analysis and interpretation of studies on stroke and the gut microbiota.

Women and stroke: disparities in clinical presentation, severity, and short- and long-term outcomes

Objectives

There are limited data from the Middle East on sex-related differences in short- and long-term stroke outcomes. We present 8 years of experience based on the Qatar stroke database.

Setting

The Qatar stroke database prospectively collects data on all stroke patients admitted to Hamad General Hospital. For this study, we compared female and male acute ischemic stroke patients on their characteristics at admission, short-term outcomes [modified Rankin Scale (mRS) score], and long-term outcomes [incidence of major adverse cardiovascular events (MACEs)].

Participants

A total of 7,300 patients [F: 1,406 (19.3%), M: 5,894 (80.7%); mean age 55.1 ± 13.3 (F: 61.6 ± 15.1, M: 53.5 ± 12.3; p < 0.001)] were admitted with acute ischemic stroke.

Results

Significantly fewer women presented within 4.5 h of onset (F: 29% vs. M: 32.8%; p = 0.01). Although women were more likely to experience severe stroke (NIHSS >10; F: 19.9% vs. M: 14.5%; p < 0.001), fewer were treated with thrombolysis (F: 9.8% vs. M: 12.1%; p = 0.02). Women experienced more medical complications (F: 11.7% vs. M: 7.4%; p < 0.001) and tended to have a more prolonged length of stay in the hospital (F: 6.4 ± 7.6 days vs. M: 5.5 ± 6.8 days; p < 0.001).

Primary and secondary outcome measures

Good outcomes at 90 days (mRS score of 0-2) were less frequent in women (F: 53.3% vs. M: 71.2%; p < 0.001). Fewer female patients were taking antiplatelets (F: 78% vs. M: 84.8%; p < 0.001) or statins (F: 81.2% vs. M: 85.7%; p < 0.001). Significantly more female patients experienced a MACE (F: 12.6% vs. M: 6.5%; p < 0.001).

Conclusion

Older age at presentation contributes to poor outcomes following acute stroke in women. Other contributing factors include delays in admission to the hospital, lower rates of thrombolysis, and lower rates of provision of preventative treatments.

DNA methylation and cardiovascular disease in humans: a systematic review and database of known CpG methylation sites

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death worldwide and considered one of the most environmentally driven diseases. The role of DNA methylation in response to the individual exposure for the development and progression of CVD is still poorly understood and a synthesis of the evidence is lacking.

RESULTS

A systematic review of articles examining measurements of DNA cytosine methylation in CVD was conducted in accordance with PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. The search yielded 5,563 articles from PubMed and CENTRAL databases. From 99 studies with a total of 87,827 individuals eligible for analysis, a database was created combining all CpG-, gene- and study-related information. It contains 74,580 unique CpG sites, of which 1452 CpG sites were mentioned in ≥ 2, and 441 CpG sites in ≥ 3 publications. Two sites were referenced in ≥ 6 publications: cg01656216 (near ZNF438) related to vascular disease and epigenetic age, and cg03636183 (near F2RL3) related to coronary heart disease, myocardial infarction, smoking and air pollution. Of 19,127 mapped genes, 5,807 were reported in ≥ 2 studies. Most frequently reported were TEAD1 (TEA Domain Transcription Factor 1) and PTPRN2 (Protein Tyrosine Phosphatase Receptor Type N2) in association with outcomes ranging from vascular to cardiac disease. Gene set enrichment analysis of 4,532 overlapping genes revealed enrichment for Gene Ontology molecular function "DNA-binding transcription activator activity" (q = 1.65 × 10^-11) and biological processes "skeletal system development" (q = 1.89 × 10^-23). Gene enrichment demonstrated that general CVD-related terms are shared, while "heart" and "vasculature" specific genes have more disease-specific terms as PR interval for "heart" or platelet distribution width for "vasculature." STRING analysis revealed significant protein-protein interactions between the products of the differentially methylated genes (p = 0.003) suggesting that dysregulation of the protein interaction network could contribute to CVD. Overlaps with curated gene sets from the Molecular Signatures Database showed enrichment of genes in hemostasis (p = 2.9 × 10^-6) and atherosclerosis (p = 4.9 × 10^-4).

CONCLUSION

This review highlights the current state of knowledge on significant relationship between DNA methylation and CVD in humans. An open-access database has been compiled of reported CpG methylation sites, genes and pathways that may play an important role in this relationship.

The age-dependent immune response to ischemic stroke

Stroke is a devastating cause of global morbidity and mortality. Ischemic brain injury triggers a profound local and systemic immune response that participates in stroke pathophysiology. In turn, this immune response has emerged as a potential therapeutic target. In order to maximize its therapeutic potential, it is critical to understand how the immune response to ischemic brain injury is affected by age - the strongest non-modifiable risk factor for stroke. The development of multi-omics and single-cell technologies has provided a more comprehensive characterization of transcriptional and cellular changes that occur during aging. In this review, we summarize recent advances in our understanding of how age-related immune alterations shape differential stroke outcomes in older versus younger organisms, highlighting studies in both experimental mouse models and patient cohorts. Wherever possible, we emphasize outstanding questions that present important avenues for future investigation with therapeutic value for the aging population.

Epigenetic mechanisms and potential therapeutic targets in stroke

Accumulating evidence indicates a central role for epigenetic modifications in the progression of stroke pathology. These epigenetic mechanisms are involved in complex and dynamic processes that modulate post-stroke gene expression, cellular injury response, motor function, and cognitive ability. Despite decades of research, stroke continues to be classified as a leading cause of death and disability worldwide with limited clinical interventions. Thus, technological advances in the field of epigenetics may provide innovative targets to develop new stroke therapies. This review presents the evidence on the impact of epigenomic readers, writers, and erasers in both ischemic and hemorrhagic stroke pathophysiology. We specifically explore the role of DNA methylation, DNA hydroxymethylation, histone modifications, and epigenomic regulation by long non-coding RNAs in modulating gene expression and functional outcome after stroke. Furthermore, we highlight promising pharmacological approaches and biomarkers in relation to epigenetics for translational therapeutic applications.

Genome-Wide Studies in Ischaemic Stroke: Are Genetics Only Useful for Finding Genes?

Ischaemic stroke is a complex disease with some degree of heritability. This means that heritability factors, such as genetics, could be risk factors for ischaemic stroke. The era of genome-wide studies has revealed some of these heritable risk factors, although the data generated by these studies may also be useful in other disciplines. Analysis of these data can be used to understand the biological mechanisms associated with stroke risk and stroke outcome, to determine the causality between stroke and other diseases without the need for expensive clinical trials, or to find potential drug targets with higher success rates than other strategies. In this review we will discuss several of the most relevant studies regarding the genetics of ischaemic stroke and the potential use of the data generated.