Cholesterol as a Risk Factor for Subarachnoid Hemorrhage: A Systematic Review

Identification of Risk Factors Influencing Hemorrhage Volume in Aneurysmal Subarachnoid Hemorrhage: A Multicenter Retrospective Study

OBJECTIVE

This multicenter retrospective study aimed to identify significant risk factors influencing hemorrhage volume in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

A total of 891 patients diagnosed with SAH were included from multiple medical centers. Data encompassing demographic characteristics, medical history, clinical parameters at admission, and radiographic findings were collected and analyzed. Univariate and multivariate logistic regression analyses were conducted to investigate associations between various risk factors and hemorrhage volume.

RESULTS

This study identifies several factors significantly associated with increased hemorrhage volume in patients with subarachnoid hemorrhage (SAH). Multivariate analysis revealed that diabetes (P = 0.022), hypertension (P = 0.047), and saccular aneurysm morphology (P = 0.008) were independent risk factors for high hemorrhage volume. Additionally, larger aneurysm size (maximum diameter: P = 0.007, neck diameter: P = 0.021) and higher systolic blood pressure after onset (P = 0.002) were also significant predictors of increased hemorrhage volume. Factors such as age (P = 0.05) and time interval to the first CT scan (P = 0.022) were found to be associated with hemorrhage volume in univariate analysis but did not maintain independent significance in multivariate regression.

CONCLUSION

This study highlights key risk factors, including diabetes, hypertension, and saccular aneurysm morphology, which independently contribute to higher hemorrhage volume in SAH patients. Management strategies focusing on early detection and control of these factors may improve clinical outcomes by reducing the risk of hemorrhagic complications. While other factors such as age and time interval to the first CT scan were associated with hemorrhage volume, they did not demonstrate independent causality in the multivariate analysis, suggesting that their role in hemorrhage volume may be secondary or context-dependent.

Metabolomic and lipidomic pathways in aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) results in a complex systemic response that is critical to the pathophysiology of late complications and has important effects on outcomes. Omics techniques have expanded our investigational scope and depth into this phenomenon. In particular, metabolomics-the study of small molecules, such as blood products, carbohydrates, amino acids, and lipids-can provide a snapshot of dynamic subcellular processes and thus broaden our understanding of molecular-level pathologic changes that lead to the systemic response after aSAH. Lipids are especially important due to their abundance in the circulating blood and numerous physiological roles. They are comprised of a wide variety of subspecies and are critical for cellular energy metabolism, the integrity of the blood-brain barrier, the formation of cell membranes, and intercellular signaling including neuroinflammation and ferroptosis. In this review, metabolomic and lipidomic pathways associated with aSAH are summarized, centering on key metabolites from each metabolomic domain.

Modifiable Risk Factors for Subarachnoid Hemorrhage: Narrative Review With an Emphasis on Common Controversies and Epidemiologic Pitfalls

Given the relatively low incidence, high prehospital death rate, substantial geographical differences, and complex disease origin (combination of genetic and environmental risk factors), epidemiologic research on subarachnoid hemorrhage (SAH) and its risk factors is challenging. In practice, we are more or less forced to exploit compromised study designs and nonrepresentative data in such circumstances where it is almost impossible to gather comprehensive data through an optimal design. For example, hospital-based patient cohorts, administrative data repositories, and short-term population-based studies from small geographical regions are often used to research the incidence, case fatality, and risk factors of SAH, regardless of their inherent and self-evident limitations. Since studies on the epidemiology of SAH focus largely on identifying possible risk factors that could aid in disease diagnostics, treatment, and prevention, we aimed to review recent evidence on modifiable risk factors for SAH. In this context, we also try to explain the methodological reasons behind some of the conflicting results and to discuss the primary strengths and limitations of different study designs used in the field of SAH epidemiology. Based on our findings, smoking, high blood pressure, and possibly low physical activity are the only risk factors with high-quality evidence supporting their causal role in SAH. In addition, since all 3 commonly used study designs in SAH epidemiology, namely, hospital-based, population-based, and administrative register-based studies, have their own strengths and limitations, the most robust risk factor estimates and other epidemiologic measures of SAH can likely be established by combining various overlapping and high-quality sources of information in the future.

High levels of blood lipid and glucose predict adverse prognosis in patients with aneurysmal subarachnoid hemorrhage

Objective

We conducted a retrospective study on the prognostic factors of aneurysmal subarachnoid hemorrhage (aSAH) patients in the author's Hospital from January 2019 to May 2023. To discuss the association of the blood lipid and glucose levels of patients with the prognosis of aSAH, and verify that high blood lipid and glucose levels are important factors affecting adverse prognosis.

Methods

All patients with aSAH were collected as the case group, which was divided into two groups according to the modified Rankin Scores (mRS), the good prognosis group (Group A, mRS ＜ 3) and the adverse prognosis group (Group B,mRS ≥3). The clinical data of age, gender, accompanied chronic diseases (hypertension, diabetes), smoking, drinking, Glasgow Coma Scale (GCS), Hunt-Hess (H-H) grade, Modified Fisher grade, total cholesterol (TC) , triglyceride (TG) , high-density cholesterol lipoprotein (HDL-C) , low-density cholesterol lipoprotein (LDL-C) , blood glucose (BG) , responsible aneurysm diameter and location were recorded too. Correlations between blood lipid and glucose levels and Modified Fisher grade were assessed by the Spearman correlation analysis. The receiver operating characteristic (ROC) curve was utilized to evaluate the diagnostic efficacy. The effect of blood lipid and glucose levels on adverse prognosis was analyzed by Logistic regression models.

Result

A total of 259 patients with aSAH were enrolled. The average age of all patients is (56.54 ± 10.52) years, including 96 males and 163 females. They were divided into Group A (n = 146) and Group B (n = 113). Univariate analysis results show that age, the levels of TC, TG, LDL-C, and BG were higher in Group B (P < 0.05). Besides, Group B had more severe GCS, H-H grade, and Modified Fisher grade than Group A, and a higher proportion of intracranial aneurysms with larger diameter (P < 0.05). Correlation analysis showed that TC, TG, LDL-C, and BG levels were positively correlated with Modified Fisher grade (P < 0.05) and H-H grade (P < 0.05). Multivariate logistic regression model analysis showed that high level of Modified Fisher grade (OR = 0.079, 95%CI: 0.027-0.230) , high level of H-H grade (OR = 0.204, 95%CI: 0.067-0.622) , TC (OR = 10.711, 95%CI: 2.457-46.700) , LDL-C (OR = 0.178, 95%CI: 0.039-0.823) and BG (OR = 1.273, 95%CI: 1.012-1.602) increased the risk of adverse prognosis. The AUC of "H-H grade", "Modified Fisher grade", "TC level", "LDL-C level" and "BG level" was 0.822, 0.885, 0.860, 0.772, and 0.721, respectively, in the ROC curve.

Conclusion

Modified Fisher grade, H-H grade, TC, LDL-C, and BG levels at admission were independent predictors of adverse prognosis of aSAH. Besides, TC, LDL-C, and BG levels were positively correlated with Modified Fisher grade and Hunt-Hess grade. What's more, high levels of TC, LDL-C, and BG combined with Modified Fisher grade and H-H grade can identify high-risk groups with adverse prognoses in aSAH patients.

Development of a predictive nomogram for 28-day mortality risk in non-traumatic or post-traumatic subarachnoid hemorrhage patients

OBJECTIVE

Subarachnoid hemorrhage (SAH) is associated with high rates of mortality and permanent disability. At present, there are few definite clinical tools to predict prognosis in SAH patients. The current study aims to develop and assess a predictive nomogram model for estimating the 28-day mortality risk in both non-traumatic or post-traumatic SAH patients.

METHODS

The MIMIC-III database was searched to select patients with SAH based on ICD-9 codes. Patients were separated into non-traumatic and post-traumatic SAH groups. Using LASSO regression analysis, we identified independent risk factors associated with 28-day mortality and incorporated them into nomogram models. The performance of each nomogram was assessed by calculating various metrics, including the area under the curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA).

RESULTS

The study included 999 patients with SAH, with 631 in the non-traumatic group and 368 in the post-traumatic group. Logistic regression analysis revealed critical independent risk factors for 28-day mortality in non-traumatic SAH patients, including gender, age, glucose, platelet, sodium, BUN, WBC, PTT, urine output, SpO2, and heart rate and age, glucose, PTT, urine output, and body temperature for post-traumatic SAH patients. The prognostic nomograms outperformed the commonly used SAPSII and APSIII systems, as evidenced by superior AUC, NRI, IDI, and DCA results.

CONCLUSION

The study identified independent risk factors associated with the 28-day mortality risk and developed predictive nomogram models for both non-traumatic and post-traumatic SAH patients. The nomogram holds promise in guiding prognosis improvement strategies for patients with SAH.

Genetic Risk Score for Intracranial Aneurysms: Prediction of Subarachnoid Hemorrhage and Role in Clinical Heterogeneity

BACKGROUND

Recently, common genetic risk factors for intracranial aneurysm (IA) and aneurysmal subarachnoid hemorrhage (ASAH) were found to explain a large amount of disease heritability and therefore have potential to be used for genetic risk prediction. We constructed a genetic risk score to (1) predict ASAH incidence and IA presence (combined set of unruptured IA and ASAH) and (2) assess its association with patient characteristics.

METHODS

A genetic risk score incorporating genetic association data for IA and 17 traits related to IA (so-called metaGRS) was created using 1161 IA cases and 407 392 controls from the UK Biobank population study. The metaGRS was validated in combination with risk factors blood pressure, sex, and smoking in 828 IA cases and 68 568 controls from the Nordic HUNT population study. Furthermore, we assessed association between the metaGRS and patient characteristics in a cohort of 5560 IA patients.

RESULTS

Per SD increase of metaGRS, the hazard ratio for ASAH incidence was 1.34 (95% CI, 1.20-1.51) and the odds ratio for IA presence 1.09 (95% CI, 1.01-1.18). Upon including the metaGRS on top of clinical risk factors, the concordance index to predict ASAH hazard increased from 0.63 (95% CI, 0.59-0.67) to 0.65 (95% CI, 0.62-0.69), while prediction of IA presence did not improve. The metaGRS was statistically significantly associated with age at ASAH (β=-4.82×10-3 per year [95% CI, -6.49×10-3 to -3.14×10-3]; P=1.82×10-8), and location of IA at the internal carotid artery (odds ratio=0.92 [95% CI, 0.86-0.98]; P=0.0041).

CONCLUSIONS

The metaGRS was predictive of ASAH incidence, although with limited added value over clinical risk factors. The metaGRS was not predictive of IA presence. Therefore, we do not recommend using this metaGRS in daily clinical care. Genetic risk does partly explain the clinical heterogeneity of IA warranting prioritization of clinical heterogeneity in future genetic prediction studies of IA and ASAH.

Selection bias in patients proposed for neurosurgical versus endovascular treatment of aneurysms of the posterior communicating artery

BACKGROUND

Microsurgical clipping and endovascular coiling are viable treatment options for posterior communicating artery (PComA) aneurysms, but there are still major limitations to evidence-based decisions regarding standard-of-care treatment. In this study, we aimed at assessing potential selection biases that may influence our ability to extract conclusions about the comparative effectiveness or efficacy of the aneurysm treatment.

OBJECTIVE

To study the patient/aneurysm characteristics as possible biases in the option for endovascular or neurosurgical treatment of PComA aneurysms.

METHODS

A single-center, retrospective cohort study was performed, including all patients with treated PComA aneurysms with neurosurgical clipping or endovascular coiling between January 2010 and January 2021. Clinical and morphological data were collected from electronic records, and statistical analysis was performed.

RESULTS

A total of 64 patients was eligible for inclusion; 24 (37.5%) patients were proposed for neurosurgical treatment, while 40 (62.5%) for endovascular treatment; 10 patients (25%) crossed over to the clipping group whereas none crossed over to the coiling side. Actual treatment analysis showed significantly higher diameters of mother vessel (t-test, p = 0.034) and aneurysm neck (Mann-Whitney, p = 0.029) in the clipping group and higher aspect and dome-to-neck ratios in the endovascular group (Mann-Whitney, p = 0.008). A significantly higher vasospasm frequency was found in the clipping group but only in the intention-to-treat analysis (Chi-square, p = 0.032).

CONCLUSION

Significant morphological differences between effective endovascular and surgical groups and differences in intention-to-treat analysis may limit the validity of a direct comparison between treatment options and suggest the presence of a possible selection bias.

Influence of socioeconomic status on the incidence of aneurysmal subarachnoid haemorrhage and clinical recovery

BACKGROUND

The relevance of socioeconomic status (SES) on the incidence of aneurysmal subarachnoid haemorrhage (aSAH) and discharge functional outcomes following treatment is not clear.

METHODS

A retrospective cross-sectional study was performed on data retrieved from the Nationwide Hospital Morbidity Database for all aSAH cases in Australia between 2012 and 2018. Information on patient characteristics, procedures performed, discharge disposition and SES were extracted. SES data was derived from classifications by the Australian Bureau of Statistics. Putative risk factors were evaluated with univariate and multivariate logistic regression analysis to identify independent predictor of unfavourable discharge outcomes (defined as death or dependency).

RESULTS

A total of 3,591 low SES patients (49.8%) were identified in our study cohort. Average crude incidence of aSAH was persistently higher among the SES disadvantaged (6.6 cases per 100,000 person-years, 95% CI 6.3 - 6.8), compared to the SES advantaged group (4.1 cases per 100,000 person-years, 95% CI 4.0-4.2) (p < 0.0001). Patients in the Low SES group were more likely to be active smokers, have type 2 diabetes mellitus, or live in non-metropolitan residence, and have overall worse discharge functional outcomes (27.7% versus 24.5%, p = 0.0015). Adjusting for well-established risk factors such as older age, and intracranial bleed (ICH and/or IVH), disadvantaged SES remained a significant predictor of poor discharge outcome following aSAH (p = 0.0003).

CONCLUSION

aSAH occurs more frequently among low SES communities, and once ruptured, there is a greater risk of poor recovery..

Dyslipidemia and rupture risk of intracranial aneurysms-a systematic review

Dyslipidemia is a well-established risk factor for coronary artery disease. However, the effect on cerebral artery disease, and more specifically the rupture risk of intracranial aneurysms, is unclear and has not yet been reviewed. We therefore performed a systematic review to investigate associations between different types of dyslipidemia and incidence of aneurysmal subarachnoid hemorrhage (aSAH). We used the MEDLINE, Embase, and Web of Science databases to identify clinical trials that compared the rupture risk among SAH patients with or without dyslipidemia. The risk of bias in each included study was evaluated using the Critical Appraisal Skills Program (CASP). Of 149 unique citations from the initial literature search, five clinical trials with a case-control design met our eligibility criteria. These studies compared aSAH patients to patients with unruptured aneurysms and found an overall inverse relationship between hypercholesterolemia and rupture risk of intracranial aneurysms. The quality assessment classified all included studies as high risk of bias. The evidence indicates that hypercholesterolemia is associated with a reduced rupture risk of intracranial aneurysms. However, it is not clear whether this relation is due to the dyslipidemic condition itself or the use of antihyperlipidemic medication.

Genetically Determined Low-Density Lipoprotein Cholesterol and Risk of Subarachnoid Hemorrhage

We evaluated whether genetically elevated low-density lipoprotein cholesterol (LDL-C) levels are associated with lower risk of intracranial aneurysms and subarachnoid hemorrhage (IA/SAH). We conducted a 2-sample Mendelian randomization (MR) study. Our primary analysis used the inverse-variance weighted method. In secondary analyses, we implemented the MR-PRESSO method, restricted our analysis to LDL-C-specific instruments, and performed multivariate MR. A 1-mmol/l increase in genetically instrumented LDL-C levels was associated with a 17% lower risk of IA/SAH (odds ratio = 0.83, 95% confidence interval = 0.73-0.94, p = 0.004). Results remained consistent in secondary and multivariate analyses (all p < 0.05). Our results provide evidence for an inverse causal relationship between LDL-C levels and risk of IA/SAH. ANN NEUROL 2021.

Development and Clinical Translation of a Perioperative Nomogram Incorporating Free Fatty Acids to Predict Poor Outcome of Aneurysmal Subarachnoid Hemorrhage Following Endovascular Treatment

Objective: A reliable prediction of clinical outcome is important for clinicians to set appropriate medical strategies in treating patients with aneurysmal subarachnoid hemorrhage (aSAH). In this study, we aim to establish a perioperative nomogram involving serum lipid signatures for predicting poor outcomes at 3 months in patients with aSAH following endovascular therapy.

Methods: Data of patients with aSAH receiving endovascular therapy were collected. Univariable and multivariable analyses were performed to screen independent predictors related to unfavorable outcomes defined by the modified Rankin Scale (mFS) ≥3. A novel nomogram based on these significant features was conducted. The clinical application of this nomogram was assessed by decision curve analysis (DCA) and clinical impact curve.

Results: A total number of patients included in this study were 213 (average age 58.9 years, 65.7% female), representing a poor 3-month outcome rate of 48.8%. Free fatty acid (FFA) levels on admission were efficient in predicting poor outcomes compared with other contents in serum lipids. Univariable and multivariable analyses revealed advanced age (P = 0.034), poor Hunt Hess (HH) (odds ratio, OR = 3.7, P < 0.001) and mFS (OR = 6.0, P < 0.001), aneurysms in the posterior circulation (OR = 4.4, P = 0.019), and higher FFA levels on admission (OR = 3.1, P = 0.021) were negative independent predictors of poor 3 months outcome. A novel nomogram composed of these significant features presented a concordance index (C-index) of 0.831 while the practical benefit was validated by DCA and clinical impact curve. An online calculator based on R programming promoted the clinical application of this nomogram.

Conclusion: Nomogram involving age, HH grade, mFS, aneurysm location, and serum FFA levels was sufficient to provide an individualized prediction of 3-month poor outcome for each patient with aSAH who underwent endovascular therapy.

Morphologic Variations in the Circle of Willis as a Risk Factor for Aneurysm Rupture in the Anterior and Posterior Communicating Arteries

BACKGROUND

Intracranial aneurysms are acquired abnormal vascular dilations. The most dangerous complication of a cerebral aneurysm is its rupture, with a high rate of mortality. This study aimed to determine whether there is an association between anatomic variations in the circle of Willis and ruptured aneurysms in the anterior and posterior communicating arteries.

METHODS

A cross-sectional study of adult patients with a diagnosis of intracranial aneurysm was carried out between March 2015 and March 2019. The patients were divided into groups of ruptured or unruptured aneurysm in the anterior and posterior communicating arteries.

RESULTS

A total of 132 patients with anterior and posterior communicating artery aneurysms were included. The presence of anatomic variation in the circle of Willis presented a statistically significant association with ruptured aneurysms (odds ratio [OR], 2.28; 95% confidence interval [CI], 1.11-4.65; P = 0.024). There was a statistically significant difference between the presence of nonspherical aneurysm and rupture (OR, 6.9; 95% CI, 3.12-15.48; P < 0.0001). Multivariate logistic regression observed smoking (OR, 2.4; 95% CI, 1.01-5.9; P = 0.4), anterior complex variations (OR, 2.68; 95% CI, 1.01-7.18; P < 0.04), and nonspherical morphology (OR, 4.7; 95% CI, 1.93-11.45; P = 0.001) presented a statistically significant association with the rupture.

CONCLUSIONS

Our results suggest that the studied variations of the circle of Willis and nonspherical morphology, in addition to playing a role in the development of cerebral aneurysms, may contribute to their rupture.

Clinical Factors Associated with the Risk of Intracranial Aneurysm Rupture in Autosomal Dominant Polycystic Kidney Disease

BACKGROUND

The occurrence of intracranial aneurysms is higher in patients with autosomal dominant polycystic kidney disease (ADPKD) than in the healthy population. However, research concerning the factors related to the risk of intracranial aneurysm rupture in patients with ADPKD is still insufficient.

OBJECTIVES

The aim of the study was to investigate the prevalence of intracranial aneurysms and aneurysmal subarachnoid hemorrhage (SAH) and to analyze the systemic factors associated with high-risk aneurysms in patients with ADPKD.

METHODS

We screened patients who underwent cerebral angiography between January 2007 and May 2017 in the ADPKD registry. Patients were examined for the presence of intracranial aneurysms and subsequently reclassified into 3 groups based on the risk of aneurysmal rupture: the aneurysm-negative (group 1), low-risk aneurysm (group 2), or high-risk aneurysm (group 3). Various systemic factors were compared, and independent factors associated with high-risk aneurysms were analyzed.

RESULTS

Among the 926 patients, 148 (16.0%) had intracranial aneurysms and 11 (1.2%) had previous aneurysmal SAH. Patients with intracranial aneurysms were further classified into group 2 (low-risk aneurysms, 15.5%) or group 3 (high-risk aneurysms, 84.5%). Age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.05, p = 0.004), female sex (OR 3.13, 95% CI 1.94-5.0 6, p < 0.001), dolichoectasia (OR 8.57, 95% CI 1.53-48.17, p = 0.015), and mitral inflow deceleration time (DT) (OR 1.01, 95% CI 1.00-1.01, p = 0.046) were independently associated with high-risk aneurysms, whereas hypercholesterolemia (OR 0.46, 95% CI 0.29-0.72, p = 0.001) was negatively associated.

CONCLUSION

In the present study among patients with ADPKD, the prevalence of intracranial aneurysms and aneurysmal SAH was 16 and 1.2%, respectively. Age, female sex, dolichoectasia, and mitral inflow DT were positively associated with high-risk aneurysms, whereas hypercholesterolemia was negatively associated. A subsequent large-scaled longitudinal study is needed to define the plausibility of the clinical parameters.

Low total cholesterol and high density lipoprotein are independent predictors of poor outcomes following aneurysmal subarachnoid hemorrhage: A preliminary report

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (aSAH) is devastating, with delayed cerebral ischemia (DCI) significantly contributing to the high morbidity and mortality rates. Cholesterol has been studied as a measure of nutritional status in other neurological pathologies, but reports examining cholesterol's effects on aSAH outcomes are sparse. This study aimed to elucidate the effect of low total cholesterol (TC) and high density lipoprotein (HDL) on mortality and DCI following aSAH.

METHODS

We performed a retrospective cohort study at a quaternary academic medical center between June 2014 and July 2018. All patients had aSAH confirmed by digital subtraction angiography and had TC measured on admission. Primary outcomes were mortality and DCI. Secondary outcome was radiographic vasospasm. Univariate and multivariate logistic regressions were performed.

RESULTS

There were 75 aSAH patients, with an average age of 58.7 ± 1.7 (range: 14-89) and Hunt & Hess score of 2.8 ± 0.1, included for analysis. Those with a low TC < 160 mg/dL had 3 times increased odds of DCI (OR = 3.4; 95 %CI: 1.3-9.0; p = 0.0175) and a nearly 5 times increased odds of death (OR = 4.9; 95 %CI: 1.1-18.3; p = 0.0339). Low HDL < 40 mg/dL was associated with 12 times increased odds of DCI (OR = 12.3; 95 %CI: 2.7-56.4; p = 0.0003) but no significant differences in death (p = 0.2205). In multivariate analysis, low TC was an independent risk factor for increased mortality (OR = 5.6; 95 %CI: 1.2-27.6; p = 0.0335) while low HDL was associated with increased risk for DCI (OR = 17.9; 95 %CI: 3.1-104.4; p = 0.0013). There was no effect of TC or HDL on radiographic vasospasm.

CONCLUSIONS

Low TC and HDL are independent predictors of increased mortality and DCI, respectively, following aSAH. Low TC and HDL may be markers of poor overall health, in addition to having some pathophysiological effect on cerebral vasculature. These results may have practical implications for the improvement of aSAH prognostication and management.

Common risk factors for major noncommunicable disease, a systematic overview of reviews and commentary: the implied potential for targeted risk reduction

Noncommunicable disease now contributes to the World Health Organization top 10 causes of death in low-, middle- and high-income countries. Particular examples include stroke, coronary heart disease, dementia and certain cancers. Research linking clinical and lifestyle risk factors to increased risk of noncommunicable disease is now well established with examples of confirmed risk factors, including smoking, physical inactivity, obesity and hypertension. However, despite a need to target our resources to achieve risk reduction, relatively little work has examined the overlap between the risk factors for these main noncommunicable diseases. Our high-level review draws together the evidence in this area. Using a systematic overview of reviews, we demonstrate the likely commonality of established risk factors having an impact on multiple noncommunicable disease outcomes. For example, systematic reviews of the evidence on physical inactivity and poor diet found each to be associated with increased risk of cancers, coronary heart disease, stroke, diabetes mellitus and dementia. We highlight the potential for targeted risk reduction to simultaneously impact multiple noncommunicable disease areas. These relationships now need to be further quantified to allow the most effective development of public health interventions in this area.

Physical activity associates with subarachnoid hemorrhage risk- a population-based long-term cohort study

Benefit of physical activity in prevention of aneurysmal subarachnoid hemorrhage (SAH) is unclear. We aimed to clarify this by studying how different types of physical activity associate with SAH risk. By following 65 521 population-based FINRISK participants prospectively from medical and autopsy registries since 1972 until 2014, we detected 543 incident SAHs. At baseline, we measured leisure-time physical activity (LTPA), occupational physical activity (OPA), and commuting physical activity (CPA) levels. The Cox model adjusted for all well-known SAH risk factors and for socioeconomic status, provided hazard ratios (HRs) for physical activity variables. Every 30-minute increase in weekly LTPA decreased SAH risk linearly in men and women HR = 0.95 (95% CI = 0.90–1.00). CPA reduced SAH risk as well, but the association diminished as participants retired. In contrast, individuals with moderate (1.41, 1.04–1.92) and high OPA (1.34, 0.99–1.81) had elevated SAH risk. Protective association of LTPA persisted in all age and hypertension groups, and was even greater in current smokers 0.88 (0.81–0.96) than non-smokers (p = 0.04 for difference). Commuting and leisure time physical activity seem to reduce SAH risk in men and women and is most beneficial for smokers. Future intervention studies should investigate whether physical activity can reduce the rupture risk of intracranial aneurysms.

Plasma cholesterol levels and brain development in preterm newborns

BACKGROUND

To assess whether postnatal plasma cholesterol levels are associated with microstructural and macrostructural regional brain development in preterm newborns.

METHODS

Sixty preterm newborns (born 24-32 weeks gestational age) were assessed using MRI studies soon after birth and again at term-equivalent age. Blood samples were obtained within 7 days of each MRI scan to analyze for plasma cholesterol and lathosterol (a marker of endogenous cholesterol synthesis) levels. Outcomes were assessed at 3 years using the Bayley Scales of Infant Development, Third Edition.

RESULTS

Early plasma lathosterol levels were associated with increased axial and radial diffusivities and increased volume of the subcortical white matter. Early plasma cholesterol levels were associated with increased volume of the cerebellum. Early plasma lathosterol levels were associated with a 2-point decrease in motor scores at 3 years.

CONCLUSIONS

Higher early endogenous cholesterol synthesis is associated with worse microstructural measures and larger volumes in the subcortical white matter that may signify regional edema and worse motor outcomes. Higher early cholesterol is associated with improved cerebellar volumes. Further work is needed to better understand how the balance of cholesterol supply and endogenous synthesis impacts preterm brain development, especially if these may be modifiable factors to improve outcomes.

Impact of Comorbidities and Smoking on the Outcome in Aneurysmal Subarachnoid Hemorrhage

The intention of this observational study is to show the significant impact of comorbidities and smoking on the outcome in aneurysmal subarachnoid hemorrhage (SAH). During this observational study 203 cases of treatment of ruptured intracranial aneurysms were analyzed. We examined and classified prospectively the 12 month outcome according to the modified Rankin Scale (mRS) considering retrospectively a history of smoking and investigated prospectively the occurrence of early and delayed cerebral ischemia between 2012 and 2017. Using logistic regression methods, we revealed smoking (odds ratio 0.21; p = 0.0031) and hypertension (odds ratio 0.18; p = 0.0019) to be predictors for a good clinical outcome (mRS 0-2). Age (odds ratio 1.05; p = 0.0092), WFNS Grade (odds ratio 6.28; p < 0.0001), early cerebral ischemia (ECI) (odds ratio 10.06; p < 0.00032) and delayed cerebral ischemia (DCI) (odds ratio 4.03; p = 0.017) were detected as predictors for a poor clinical outcome. Significant associations of occurrence of death with hypertension (odds ratio 0.12; p < 0.0001), smoking (odds ratio 0.31; p = 0.048), WFNS grade (odds ratio 3.23; p < 0.0001) and age (odds ratio 1.09; p < 0.0001), but not with ECI (p = 0.29) and DCI (p = 0.62) were found. Smoking and hypertension seem to be predictors for a good clinical outcome after aneurysmal SAH.

Polymorphism and plasma levels of apolipoprotein E and the risk of aneurysmal subarachnoid hemorrhage in a Chinese population: a case-control study

Background

Aneurysmal subarachnoid hemorrhage (aSAH) is the most common types of subarachnoid hemorrhage, which is a critical clinical problem with high morbidity, mortality, and economic impact. Recent studies have shown that APOE was a genetic risk factor of aSAH, however, the studies lack consistent conclusions and the evidence from Chinese Han population is rare.

Objective

To determine the relationship between APOE polymorphism and the incidence of aSAH in Chinese Fujian Han population and explore the possible mechanism of ApoE in the pathogenesis of aSAH.

Methods

A total of 131 patients newly diagnosed with aSAH were selected as aSAH group and 137 healthy subjects were selected as the control group. All the samples were analyzed for blood lipids and serum ApoE levels, and ApoE genotype was determined by a commercial chip and further confirmed with Sanger sequencing. An adjusted multivariate logistic regression analysis was carried out to estimate the effects of APOE polymorphism on the risk of aSAH.

Results

Compared with the controls, the serum TC, HDL-C and ApoA1 levels in aSAH were significantly lower: TC (4.52 ± 1.38 vs. 5.11 ± 0.86 mmol/L, P < 0.001), HDL-C (1.23 ± 0.46 vs. 1.44 ± 0.32 mmol/L, P < 0.001) and ApoA1 (1.20 ± 0.32 vs. 1.38 ± 0.25 g/L, P < 0.001). The distribution of ε2/ε3 genotype (19.08% vs. 9.49%, P = 0.038) and ε2 allele frequency (11.07% vs. 5.84%, P = 0.039) was significantly higher in aSAH than the healthy controls. The multivariate logistic regression identified that ApoE ε2 allele was independently associated with aSAH (OR = 2.083; and 95% CI = 1.045-4.153, P = 0.037). The serum ApoE in aSAH were significantly higher than controls (53.03 ± 24.64 vs. 45.06 ± 12.84 mg/L, P = 0.010).

Conclusion

APOE polymorphism might be associated with the incidence of aSAH in Chinese Fujian Han population. ApoE ε2 may be a risk factor for the incidence of aSAH, which may be related with the impacts of ApoE genotypes for the serum lipids, especially for the plasma levels of ApoE.

Adverse lipid profile elevates risk for subarachnoid hemorrhage: A prospective population-based cohort study

BACKGROUND AND AIMS

Studies report that both high and low total cholesterol (TC) elevates SAH risk. There are few prospective studies on high-density lipoproteins (HDL-C) and low-density lipoproteins (LDL-C), and apparently none concerns apolipoproteins A and B. We aimed to clarify the association between lipid profile and SAH risk.

METHODS

The National FINRISK study provided risk-factor data recorded at enrolment between 1972 and 2007. During 1.52 million person-years of follow-up until 2014, 543 individuals suffered from incident hospitalized SAH or outside-hospital-fatal SAH. Cox proportional hazards model was used to calculate the hazard ratios and multiple imputation predicted ApoA1, ApoB, and LDL-C values for cohorts from a time before apolipoprotein-measurement methods were available.

RESULTS

One SD elevation (1.28 mmol/l) in TC elevated SAH risk in men (hazard ratio (HR) 1.15 (95% CIs 1.00-1.32)). Low HDL-C levels increased SAH risk, as each SD decrease (0.37 mmol/l) in HDL-C raised the risk in women (HR 1.29 (95% CIs 1.07-1.55)) and men (HR 1.20 (95% CIs 1.14-1.27)). Each SD increase (0.29 g/l) in ApoA1 decreased SAH risk in women (HR 0.85 (95% CIs 0.74-0.97)) and men (HR 0.88 (95% CIs 0.76-1.02)). LDL-C (SD 1.07 mmol/l) and ApoB (SD 0.28 g/l) elevated SAH risk in men with HR 1.15 (95% CIs 1.01-1.31) and HR 1.26 (95% CIs 1.10-1.44) per one SD increase. Age did not change these findings.

CONCLUSIONS

An adverse lipid profile seems to elevate SAH risk similar to its effect in other cardiovascular diseases, especially in men. Whether SAH incidence diminishes with increasing statin use remains to be studied.

Lipid-Lowering Agents and High HDL (High-Density Lipoprotein) Are Inversely Associated With Intracranial Aneurysm Rupture

BACKGROUND AND PURPOSE

Growing evidence from experimental animal models and clinical studies suggests the protective effect of statin use against rupture of intracranial aneurysms; however, results from large studies detailing the relationship between intracranial aneurysm rupture and total cholesterol, HDL (high-density lipoprotein), LDL (low-density lipoprotein), and lipid-lowering agent use are lacking.

METHODS

The medical records of 4701 patients with 6411 intracranial aneurysms diagnosed at the Massachusetts General Hospital and the Brigham and Women's Hospital between 1990 and 2016 were reviewed and analyzed. Patients were separated into ruptured and nonruptured groups. Univariable and multivariable logistic regression analyses were performed to determine the effects of lipids (total cholesterol, LDL, and HDL) and lipid-lowering medications on intracranial aneurysm rupture risk. Propensity score weighting was used to account for differences in baseline characteristics of the cohorts.

RESULTS

Lipid-lowering agent use was significantly inversely associated with rupture status (odds ratio, 0.58; 95% confidence interval, 0.47-0.71). In a subgroup analysis of complete cases that includes both lipid-lowering agent use and lipid values, higher HDL levels (odds ratio, 0.95; 95% confidence interval, 0.93-0.98) and lipid-lowering agent use (odds ratio, 0.41; 95% confidence interval, 0.23-0.73) were both significantly and inversely associated with rupture status, whereas total cholesterol and LDL levels were not significant. A monotonic exposure-response curve between HDL levels and risk of aneurysmal rupture was obtained.

CONCLUSIONS

Higher HDL values and the use of lipid-lowering agents are significantly inversely associated with ruptured intracranial aneurysms.

Risk Factors for Unfavorable Outcome in Aneurysmal Subarachnoid Hemorrhage Revisited; Odds and Ends

Objectives

To evaluate the odds for unfavorable outcome of each risk factor and a combination of them in patients with aneurysmal subarachnoid hemorrhage (SAH) undergoing surgical clipping in Southern Iran.

Methods

A total of 367 patients who were operated between March 2007 and March 2016 due to aneurysmal SAH were analyzed according to patients' factors, aneurysm characteristics and intra-operative data. Correlation between outcomes of patients measured by modified Rankin Scale at 6-months with each factor were analyzed. Market Basket analysis was also used to identify the odds of unfavorable outcome for combinations of factors.

Results

A total of 367 patients, including 199 females and 168 males with a mean age of 47.27± 11.53 years, who underwent operation between March 2007 and March 2016 due to aneurysmal SAH were analyzed. Unlike gender, higher age was associated with unfavorable outcome. Ischemic heart disease, Duration of operation and amount of bleeding were also found to increase the odds of unfavorable outcome (p=0.01, 0.02, 0.04 respectively). DM, Cigarette smoking and opium addiction as well as the location and multiplicity of aneurysms did not have an adverse effect on outcome. (p≥0.05).

Conclusion

Among the numerous risk factors presumed to result in unfavorable outcome in aneurysmal SAH, only older age, duration of operation more than 60 minutes, previous known history of ischemic heart disease, poorer clinical grade and intra-operative bleeding more than 500 mL were found to be significant factors.

Stroke Incidence by Major Pathological Type and Ischemic Subtypes in the Auckland Regional Community Stroke Studies: Changes Between 2002 and 2011

BACKGROUND AND PURPOSE

Major pathological stroke types (ischemic stroke [IS], primary intracerebral hemorrhage [ICH], and subarachnoid hemorrhage) and IS subtypes, have differing risk factors, management, and prognosis. We report changes in major stroke types and IS subtypes incidence during 10 years using data from the ARCOS (Auckland Regional Community Stroke Study) III performed during 12 months in 2002 to 2003 and the fourth ARCOS study (ARCOS-IV) performed in 2011 to 2012.

METHODS

ARCOS-III and ARCOS-IV were population-based registers of all new strokes in the greater Auckland region (population aged >15 years, 1 119 192). Strokes were classified into major pathological types (IS, ICH, subarachnoid hemorrhage, and undetermined type). Crude annual age-, sex-, and ethnic-specific stroke incidence with 95% confidence intervals was calculated. ISs were subclassified using TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria into 5 etiologic groups. Rate ratios with 95% confidence intervals were calculated for differences in age-standardized rates between the 2 studies.

RESULTS

In ARCOS-IV, there were 1329 (81%) ISs, 211 (13%) ICHs, 79 (5%) subarachnoid hemorrhages, and 24 (1%) undetermined type strokes. The proportional distribution of IS subtypes was 29% cardioembolism, 21% small-vessel occlusion, 15% large-artery atherosclerosis, 5% other determined etiology, and 31% undetermined type. Between 2002 and 2011, age-standardized incidence decreased for subarachnoid hemorrhage (rate ratios, 0.73; 95% confidence intervals, 0.54-0.99) and undetermined type (rate ratios, 0.14; 95% confidence intervals, 0.09-0.22). Rates were stable for IS and ICH. Among IS subtypes, large-artery atherosclerosis and small-vessel occlusion rates increased significantly. The frequency of all risk factors increased in IS. Ethnic differences were observed for both stroke subtype rates and their risk factor frequencies.

CONCLUSIONS

A lack of change in IS and ICH incidence may reflect a trend toward increased incidence of younger strokes. Increased rates of large-artery atherosclerosis and small-vessel occlusion are associated with increased smoking and high blood pressure. Ethnic differences in the proportional distribution of pathological stroke subtypes suggest differential exposure and susceptibility to risk factors.

Association of high-density lipoprotein cholesterol concentration with different types of stroke and coronary heart disease: The Japan Public Health Center-based prospective (JPHC) study

BACKGROUND AND AIMS

Although low high-density lipoprotein (HDL) cholesterol concentration is an established risk factor for coronary heart disease (CHD), information regarding subtypes of stroke is very limited, especially in Asian populations.

METHODS

A prospective study was conducted among 30,736 individuals aged 40-69 years, who lived in nine communities in Japan and did not have a history of cardiovascular disease (CVD). CHD and stroke, including its subtypes, were assessed, and sex-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for outcomes were estimated according to quintiles of HDL cholesterol using Cox proportional models adjusted for other CVD risk factors.

RESULTS

We identified 296 CHD and 1712 stroke events over a median 15 yr of follow-up. HDL cholesterol concentration showed an inverse association with CHD in men and women. A low HDL cholesterol concentration slightly raised the risk for total strokes in men, but not in women. When analyzed by subtypes, we observed an inverse relationship between HDL cholesterol concentration and the incidence of lacunar infarction, with an adjusted HR for the lowest quintile of HDL cholesterol concentration compared with the highest quintile of 1.63 (95% CI, 1.00-2.66) in men and 1.97 (95% CI, 1.19-3.26) in women. HDL cholesterol concentration was positively associated with the risk of intracerebral hemorrhage (ICH) in a linear manner in women (p for trend = 0.028), but not in men.

CONCLUSIONS

The associations of HDL cholesterol concentration with lacunar infarction and ICH may be related to different functional properties of HDL rather than to its protective function against lipid-rich atherosclerosis.