Association of genetic polymorphisms of claudin-1 with small vessel vascular dementia.

The most recent hypothesis of the development of small vessel vascular dementia (VaD) emphasises the role of blood-brain barrier (BBB) dysfunction. It is hypothesised that certain genetic polymorphisms of the BBB tight junction claudin-1 protein, in combination with adverse environmental risk factors, increase the risk of BBB dysfunction and small vessel VaD. In this case-control study, 97 control participants, with a mean Mini Mental State Exam (MMSE) score of 29.1, and 38 VaD participants were recruited and completed a questionnaire on their medical history and lifestyle factors. Blood was also collected and two single nucleotide polymorphisms (SNPs), rs17501010 and rs893051 of claudin-1 genotyping, were analysed by real-time polymerase chain reaction (PCR) assay. A significantly higher frequency of all rs893051 SNP genotypes (GC and CC) was found in the VaD population (OR=4.8, P=0.006 and OR=6, P<0.001 respectively). Patients with TT genotype of rs17501010 were also more likely to have VaD (OR=3.25, P=0.022). Stratification analysis revealed that having combined haplotype GC+CC of rs893051 and lipid disorders was associated with higher risk of VaD (OR=9.9, P<0.001). For patients with type 2 diabetes the odds ratio of VaD increased significantly in GC+CC genotypes of rs893051 (OR=12.57, P<0.0001) and GT+TT of rs17501010 (OR=5.33, P=0.01).

Involvement of single nucleotide polymorphisms of junction adhesion molecule with small vessel vascular dementia.

Objectives: It is now recognized that blood brain barrier (BBB) leakage occurs in cerebral small vascular disease (CSVD) and plays a significant role in the pathophysiology of vascular dementia. We hypothesized that genetic polymorphisms of junctional adhesion molecule-A (JAM-A) (which may result in compromised structure of tight junction proteins that form the BBB) in combination with cerebrovascular risk factors hypertension, lipid disorders, and type 2 diabetes may result in BBB leakage and increase the individual's risk of CSVD-related dementia. Methods: In this case-control study, 97 controls with a mean Mini-Mental State Exam (MMSE) score of 29 and 38 CSVD-related vascular dementia participants (mean MMSE score of 19) were recruited. Bloods were collected for the analysis of two common single nucleotide polymorphisms (SNPs) of the JAM-A genotypes rs790056 and rs2481084 using real-time polymerase chain reaction (PCR) assay. Medical history of hypertension, hyperlipidemia, and diabetes was collected for all participants. Results: Polymorphisms of genotype JAM-A SNP rs790056 showed statistically significant result when the subgroup with hyperlipidemia was analyzed (OR = 3.130, p = 0.042 for TC + CC genotypes with hyperlipidaemia vs controls). Similar result was found with diabetes (OR = 4.670, p = 0.031 for TC + CC genotypes vs controls). No significant result was found with hypertension. Borderline results of statistical significance were found for JAM-A SNP rs2481084 with hyperlipidemia (OR = 3.210, p = 0.054 for TC + CC genotypes vs controls) and with diabetes (OR = 3.620, p = 0.069 for TC + CC genotypes vs controls) but not for hypertension. The borderline results might have been due to lack of statistical power because of small sample size. Conclusions: These results lend further support that cerebrovascular risk factors interact with genetic polymorphisms of BBB proteins to increase the risk of vascular dementia.

Delirium post-stroke: short- to long-term effect on anxiety and depression compared to effect on cognition.

Background Delirium is common after stroke and has significant negative impact on mortality, morbidity, cognitive function, and institutionalization. Despite these known effects, any impact of delirium on the emotional well-being of stroke survivors is unclear. Methods A post hoc analysis was performed on our prospective cohort study of 156 stroke patients. Hospital Anxiety and Depression (HAD) scale scores were compared between patients with delirium and patients without delirium at 1-month, 6-month, and 12-month post-stroke. Results Contrary to the negative impact of delirium on cognition and functional status, we did not discern any influence on HAD scale scores in the short to long term. The median scores of the HAD anxiety scale were 4 (interquartile range IQR 3) at 1 month, 5.5 (IQR 8.75) at 6 months, and 6 (IQR 5) at 12 months in the delirium group compared to 5 (IQR 7) at 1 month (p = 0.6), 4 (IQR 7) at 6 months (p = 0.4), and 6 (IQR 5.75) at 12 months (p = 0.9) in the non-delirium group, respectively. Similarly, the median scores of the HAD depression scale were 5 (IQR 4) at 1 month, 4 (IQR 6.5) at 6 months, and 3 (IQR 6) at 12 months in the delirium group compared to 6 (IQR 5.75) at 1 month (p = 0.9), 5 (IQR 7) at 6 months (p = 0.9), and 6 (IQR 5) at 12 months (p = 0.5) in the non-delirium group. Conclusion Delirium may not have a significant effect on the development of anxiety or depression after stroke which differs in its effect on cognitive function and functional status.