Vascular risk factors for idiopathic normal pressure hydrocephalus: a systematic review and meta-analysis

The contribution of cerebral small vessel disease in idiopathic normal pressure hydrocephalus: Insights from a prospective cohort study

INTRODUCTION

Idiopathic normal pressure hydrocephalus (iNPH) and cerebral small vessel disease (CVSD) are age-related diseases, but their prevalence and clinical relationship are unclear.

METHODS

This prospective cohort study enrolled 95 patients with probable iNPH in China and evaluated their CSVD burden using magnetic resonance imaging. Linear regression models were used to analyze the association between CSVD scores and clinical outcomes.

RESULTS

The results showed 78% of the patients had at least one CSVD imaging marker, and higher total CSVD scores were significantly associated with declines in attention, executive function, psychomotor speed, and gait performance after multivariate adjustments. However, the preoperative CSVD score did not affect the post-shunt improvement in modified Rankin scale or iNPH grading scale scores.

DISCUSSION

Our findings suggest that CSVD is prevalent in patients with iNPH and is associated with more severe symptoms, but it may not affect shunt outcomes. Future studies are needed to elucidate the underlying mechanisms.

HIGHLIGHTS

We found that 78% of the patients with idiopathic normal pressure hydrocephalus (iNPH) had at least one type of cerebral small vessel disease (CSVD) imaging marker. The CSVD burden aggravates cognitive and gait impairments in patients with iNPH but may not affect shunt outcomes. The effects of different imaging markers of CSVD on cognition and gait are different and worthy of further investigation.

A Bidirectional Mendelian Randomization Study of the Causal Association Between Ischemic Stroke, Coronary Heart Disease, and Hydrocephalus

BACKGROUND

The association among coronary heart disease, ischemic stroke, and hydrocephalus remains ambiguous.

OBJECTIVES

There is a need for a Mendelian randomization study to evaluate the underlying causality between coronary heart disease, ischemic stroke, and hydrocephalus.

METHODS

The data source utilized genome-wide association studies, employing a threshold of p < 5 × 10-8 to identify single nucleotide polymorphisms strongly linked to ischemic stroke and coronary heart disease as instrumental variables (IVs). Five methods-inverse variance weighted (IVW), Mendelian randomization (MR) Egger, Weighted Median, Weighted mode, and Simple mode-utilized the selected IVs to estimate the causality between ischemic stroke, coronary heart disease, and hydrocephalus.

RESULTS

The IVW demonstrated that ischemic stroke and coronary heart disease serve as risk factors for hydrocephalus (odds ratio [OR] = 1.650, 95% CI: 1.066-2.554, p = 0.025; OR = 1.307, 95% CI: 1.023-1.668, p = 0.032). Both the MR-Egger intercept test and Cochran's Q test affirmed the relative reliability of the IVW analysis results. However, no evidence of a reverse causation was observed between hydrocephalus and coronary heart disease or ischemic stroke.

CONCLUSIONS

Coronary heart disease and Ischemic stroke may increase the risk of hydrocephalus.

The impact of telomere length on the risk of idiopathic normal pressure hydrocephalus: a bidirectional Mendelian randomization study

Idiopathic normal pressure hydrocephalus (iNPH) affects mainly aged populations. The gradual shortening of telomere length (TL) is one of the hallmarks of aging. Whereas the genetic contribution of TL to the iNPH is incompletely understood. We aimed to investigate the causal relationship between TL and iNPH through the Mendelian randomization (MR) analysis. We respectively obtained 186 qualified single nucleotide polymorphisms (SNPs) of TL and 20 eligible SNPs of iNPH for MR analysis. The result of MR analysis showed that genetically predicted longer TL was significantly associated with a reduced odd of iNPH (odds ratio [OR] = 0.634 95% Confidence interval [CI] 0.447-0.899, p = 0.011). The causal association remained consistent in multivariable MR (OR = 0.530 95% CI 0.327-0.860, p = 0.010). However, there was no evidence that the iNPH was causally associated with the TL (OR = 1.000 95% CI 0.996-1.004, p = 0.955). Our study reveals a potential genetic contribution of TL to the etiology of iNPH, that is a genetically predicted increased TL might be associated with a reduced risk of iNPH.

10-year mortality, causes of death and cardiovascular comorbidities in idiopathic normal pressure hydrocephalus

OBJECTIVE

The objective was to investigate 10-year mortality, causes of death and cardiovascular comorbidity in idiopathic normal pressure hydrocephalus (iNPH) and to evaluate their mutual associations.

METHODS

This prospective cohort study included 176 CSF-shunted iNPH patients, and 368 age- and sex-matched controls. At inclusion, participants were medically examined, had blood analyzed and answered a questionnaire. The vascular comorbidities investigated were smoking, diabetes, body mass index, blood pressure (BP), hyperlipidemia, kidney function, atrial fibrillation and, cerebro- and cardiovascular disease.

RESULTS

Survival was observed for a mean period of 10.3 ± 0.84 years. Shunted iNPH patients had an increased risk of death compared to controls (hazard ratio (HR) = 2.5, 95% CI 1.86-3.36; p < 0.001). After 10 years, 50% (n = 88) of iNPH patients and 24% (n = 88) of the controls were dead (p < 0.001). The risk of dying from cardiovascular disease, falls and neurological diseases were higher in iNPH (p < 0.05). The most common cause of death in iNPH was cardiovascular diseases (14% vs 7% for controls). Seven out of nine iNPH dying from falls had subdural hematomas. Systolic BP (HR = 0.985 95% CI 0.972-0.997, p = 0.018), atrial fibrillation (HR = 2.652, 95% CI 1.506-4.872, p < 0.001) and creatinine (HR = 1.018, 95% CI 1.010-1.027, p < 0.001) were independently associated with mortality for iNPH.

DISCUSSION

This long-term and population-matched cohort study indicates that in spite of CSF-shunt treatment, iNPH has shorter life expectancy. It may be important to treat iNPH in supplementary ways to reduce mortality. Both cardiovascular comorbidities and lethal falls are contributing to the excess mortality in iNPH and reducing these preventable risks should be an established part of the treatment plan.

Immunological Profile and Markers of Endothelial Dysfunction in Elderly Patients with Cognitive Impairments

The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD). Socio-demographic, lifestyle, and cognitive data were obtained. Biochemical, hematological, and immunological analyses were carried out, and extracellular vesicles (EVs) with endothelial CD markers were assessed. The greatest number of significant deviations from conditionally healthy donors (HDs) of the same age were registered in the SIVD group, a total of 20, of which 12 were specific and six were non-specific but with maximal differences (as compared to the other three groups) from the HDs group. The non-specific deviations were for the MOCA (Montreal Cognitive Impairment Scale), the MMSE (Mini Mental State Examination) and life satisfaction self-assessment scores, a decrease of albumin levels, and ADAMTS13 (a Disintegrin and Metalloproteinase with a Thrombospondin Type 1 motif, member 13) activity, and an increase of the VWF (von Willebrand factor) level. Considering the significant changes in immunological parameters (mostly Th17-like cells) and endothelial CD markers (CD144 and CD34), vascular repair was impaired to the greatest extent in the DM group. The AIS patients showed 12 significant deviations from the HD controls, including three specific to this group. These were high NEFAs (non-esterified fatty acids) and CD31 and CD147 markers of EVs. The lowest number of deviations were registered in the CCCI group, nine in total. There were significant changes from the HD controls with no specifics to this group, and just one non-specific with a maximal difference from the control parameters, which was α1-AGP (alpha 1 acid glycoprotein, orosomucoid). Besides the DM patients, impairments of vascular repair were also registered in the CCCI and AIS patients, with a complete absence of such in patients with dementia (SIVD group). On the other hand, microvascular damage seemed to be maximal in the latter group, considering the biochemical indicators VWF and ADAMTS13. In the DM patients, a maximum immune response was registered, mainly with Th17-like cells. In the CCCI group, the reaction was not as pronounced compared to other groups of patients, which may indicate the initial stages and/or compensatory nature of organic changes (remodeling). At the same time, immunological and biochemical deviations in SIVD patients indicated a persistent remodeling in microvessels, chronic inflammation, and a significant decrease in the anabolic function of the liver and other tissues. The data obtained support two interrelated assumptions. Taking into account the primary biochemical factors that trigger the pathological processes associated with vascular pathology and related diseases, the first assumption is that purine degradation in skeletal muscle may be a major factor in the production of uric acid, followed by its production by non-muscle cells, the main of which are endothelial cells. Another assumption is that therapeutic factors that increase the levels of endothelial progenitor cells may have a therapeutic effect in reducing the risk of cerebrovascular disease and related neurodegenerative diseases.