INTRODUCTION:Flow-diverting (FD) stents are increasingly used to treat small, unruptured intracranial aneurysms (UIA), but high-quality, unbiased data on initial complications and clinical outcomes were limited in previous literature reviews. We updated the literature review to assess quality, potential bias, complications and short-term outcomes in studies on FD-stents for UIAs. PATIENTS AND METHODS:We systematically searched PubMed, Embase and Cochrane Library until January 9, 2025 for studies on FD-stents for UIAs. We assessed methodological quality using the methodological index for non-randomised studies (poor: 0-9, moderate: 10-13, good: 14-16), and financial conflicts of interest. The primary outcome was neurological outcome according to a validated outcome scale at 1-3 months after treatment. Secondary outcomes were clinical worsening and complications. RESULTS:We included 13 studies with 743 patients and 806 UIAs, of which 88.4% (95% CI: 85.7%-91.2%) were <10 mm. All studies were uncontrolled. The methodological quality was poor in six and moderate in seven studies. Financial conflicts of interest were reported in six studies. At 1-3 months after treatment, the proportion of patients were for mRS ⩾1 13.3% (95% CI: 10.0%-16.6%), mRS ⩾2 5.3% (95% CI: 3.2%-7.5%), mRS ⩾3 2.4% (95% CI: 0.1%-3.9%) and neurological worsening 3.1% (95% CI: 1.5%-4.6%). Complications within 3 months occurred in 12.7% (95% CI: 10.3%-15.0%). DISCUSSION AND CONCLUSION:The literature on FD-stents is methodologically weak and potentially biased by financial interests but still shows relevant proportions of complications and post-treatment morbidity. Currently, there are no good data supporting the use of FD-stents for UIAs where standard treatment options are available. Randomised-controlled trials are needed to compare safety, efficacy and durability between FD-stents and coiling or clipping.

INTRODUCTION:While increased female susceptibility to intracranial aneurysm development and rupture is well-known, data on sex differences in case fatality rates (CFR) after aneurysmal subarachnoid haemorrhage (aSAH) remain conflicting. We aimed to investigate sex differences in 90-day CFR post-aSAH and identify explanatory factors. PATIENTS AND METHODS:The UK Biobank is a prospective population-based cohort study, including 502,411 participants, with baseline assessments between 2006 and 2010. Participants who developed aSAH during follow-up were identified through linkage with hospitalisation records and national death registries. Primary outcome was 90-day CFR post-aSAH. Kaplan-Meier survival analysis and multivariable Cox proportional hazard regression assessed sex disparities in CFR and potential explanatory factors. RESULTS:We included 990 participants with aSAH, 634 (64.0%) females (age 66.0 ± 8.4) and 356 males (36.0%) (65.1 ± 8.6). At 90 days, 214 of 634 females (33.8%) and 98 of 356 males (27.5%) had died (OR 1.34; 95% CI, 1.01-1.78). Survival analysis demonstrated a sex difference in 90-day CFR (log-rank P = .046) with early divergence and consistently lower survival probability in females. After adjusting for age and covariates that varied by sex at baseline and at time of aSAH, hazard ratio (HR) for case fatality in females was 1.15 (95% CI, 0.90-1.49). In sex-specific multivariable models, HRs for case fatality for age were 1.04 (95% CI, 1.02-1.06) in females and 1.04 (95% CI, 1.01-1.07) in males; for anti-hypertensives use 1.76 (95% CI, 1.23-2.51) and 1.98 (95% CI, 1.23-3.17); and for current smoking 1.87 (95% CI, 1.31-2.67) and 1.64 (95% CI, 0.95-2.82). DISCUSSION AND CONCLUSION:Females had a higher unadjusted 90-day CFR post-aSAH. This sex difference is partially explained by higher age at aSAH and differences in modifiable baseline risk factors such as hypertension and smoking.

BACKGROUND AND OBJECTIVES:A 2005 review identified smoking, hypertension, and excessive alcohol intake as the most important risk factors of aneurysmal subarachnoid hemorrhage (aSAH), but data on other factors remained inconclusive. While aSAH is more prevalent in female participants, evidence on sex differences and female-specific factors remains limited. Comprehensive identification of all risk factors, including potential sex differences and female-specific factors, is essential for improving prevention and accurately assessing aSAH risk. We aimed to determine whether there is now greater certainty around previously inconclusive risk factors, identify any new emerging factors, and explore sex differences in both established and emerging risk factors. METHODS:We conducted a systematic review and meta-analysis of cohort and case-control studies on prevalent lifestyle exposures, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. These exposures included smoking, hypertension, alcohol abuse, oral contraception, hormone replacement therapy, hypercholesterolemia, rigorous physical activity, lean body mass index, and diabetes. We calculated pooled sex-specific relative risks (RRs) and odds ratios (ORs) with 95% CIs for overall risk and female-to-male ratios of RRs (RRRs) and ORs (RORs) for sex comparisons. RESULTS:We included 67 studies (34 cohort [8 with sex-specific data], 33 case-control [6 with sex-specific data]; n = 5,743,262; 57% female). A sex-specific association was found for current smoking (RRR 1.53, 95% CI 1.05-2.23), but not for hypertension (RRR 1.50, 95% CI 0.78-2.89) or excessive alcohol intake (RRR 0.46, 95% CI 0.13-1.63). Regular rigorous exercise (RR 0.74, 95% CI 0.53-1.04; OR 0.69, 95% CI 0.57-0.83) and diabetes (RR 0.75, 95% CI 0.55-1.02; OR 0.52, 95% CI 0.41-0.65) were associated with reduced risk, without sex-specific associations. Data on hypercholesterolemia (RR 1.24, 95% CI 0.97-1.58; OR 0.52, 95% CI 0.37-0.74) and lean BMI (RR 1.31, 95% CI 1.15-1.50; OR 1.39, 95% CI 0.74-2.60) were inconsistent and showed no sex-specific associations. Hormone replacement therapy (RR 1.03, 95% CI 0.72-1.48) and oral contraceptive use (RR 5.40, 95% CI 0.68-42.57) were limited to female patients, with current users compared with never users. Most studies contained potential sources of bias. DISCUSSION:Current smoking, but not hypertension or excessive alcohol, has a stronger association with aSAH in female patients than in male patients. Regular exercise and diabetes are associated with a reduced risk, with no sex-specific associations. Data on female-specific factors remain inconsistent. Targeted smoking prevention may particularly benefit female patients. Large-scale studies are needed to clarify the role of female-specific factors in explaining the higher incidence of aSAH in female patients.

BACKGROUND AND PURPOSE:The performance of the current prediction models for intracranial aneurysm growth and rupture is suboptimal, and new markers are needed to improve prediction. There is a strong need for longitudinal studies that use standardized morphologic parameters. In this longitudinal study, we aimed to identify standardized 3D quantified morphologic parameters as predictors of aneurysm growth or rupture during long-term follow-up. MATERIALS AND METHODS:We used a database of consecutive patients with saccular unruptured intracranial aneurysms diagnosed between 2008 and 2018. Using a retrospective case-cohort design, we included a computer-generated random sample of aneurysms from the full cohort and aneurysms with growth or rupture during follow-up outside the random sample. The case-cohort design is efficient for low-incidence outcomes while maintaining the temporal association between exposure and outcome. Aneurysms were annotated on baseline CTA or MRA images, and 3D morphologic parameters were quantified. Univariable and multivariable Cox proportional hazards models were used to identify 3D morphologic predictors of either aneurysm growth or rupture. An inverse sampling probability weight was applied to obtain unbiased estimates of the hazard ratios. RESULTS:We included 278 patients (median age, 59 years [interquartile range, 50-66]; 209 women) with 327 aneurysms, of which 239 aneurysms were stable during follow-up (73%), 68 grew without subsequent rupture (21%), 7 grew with subsequent rupture (2%), and 13 ruptured without preceding growth (4%). In the multivariable model for growth prediction (median follow-up, 4.1 years [interquartile range, 1.9-7.1]), major axis (hazard ratio, 1.16; 95% CI, 0.84-1.61) and shape index (hazard ratio, 1.53; 95% CI, 0.76-3.08) were retained, with a c-statistic of 0.56 (95% CI, 0.49-0.63). The same parameters were retained in the multivariable model for prediction of rupture (median follow-up, 4.5 years [interquartile range, 2.1-7.3]): major axis (hazard ratio, 2.27; 95% CI, 1.36-3.80) and shape index (hazard ratio, 3.33; 95% CI, 0.95-11.62), with a c-statistic of 0.85 (95% CI, 0.77-0.94). CONCLUSIONS:We identified major axis and shape index as candidate 3D-quantified morphologic predictors of both aneurysm growth and rupture, but only for rupture did they demonstrate good discriminative power in our cohort. These parameters will need external validation and should be integrated with existing clinical prediction models.

BACKGROUND:Preventive treatment of unruptured intracranial aneurysms (UIAs) has the potential to reduce aneurysmal subarachnoid hemorrhage (SAH) incidence. Population-wide screening (PWS) for UIAs has been disregarded, as it remains unclear how to manage low-risk UIAs. Higher cost for SAH treatment, along with improvements in UIA treatment decision-making, might improve the risk-benefit and cost-benefit ratios for PWS. Currently, blood-based screening tests for UIAs are under development and might be suitable for use in PWS. AIMS:This study sets out to identify what health economic criteria should be met by a hypothetical UIA screening test to justify PWS. METHODS:A Markov model was built to compare PWS versus standard of care. Model parameterization was done using real-world data derived from the population cared for by the RWTH Aachen University Hospital. Data in relation to SAH were derived from a prospective registry of consecutive SAH patients (n = 275). In addition, a database of newly diagnosed UIAs was retrospectively collected (n = 139). Incremental cost-effectiveness ratios (ICERs) were calculated to illustrate the annual cost per additional quality-adjusted life year (QALY). Sensitivity analyses were performed to determine at which price point the PWS strategy would become cost-effective based on different levels of willingness-to-pay (WTP). RESULTS:In a one-way sensitivity analysis, the price of a hypothetical screening test was varied between €1 and €811.3 (mean cost of magnetic resonance angiography). In case of a WTP of €50,000 per QALY gained, the cost per test may be €225.72 and remain cost-effective. If the same test could also be used for watchful-waiting in low-risk patients (i.e. assess the risk of aneurysm growth), the price may increase up to €294.19. There is no price point at which PWS would become dominant and yield negative ICERs. CONCLUSION:PWS for UIAs is unlikely to be cost-effective, even with new blood screening technologies. However, once patents expire, and price monopolies are broken, use of such technologies may become more attractive for health policymakers, depending on their WTP.

BACKGROUND AND PURPOSE:Previous studies have shown that intracranial aneurysm wall enhancement (AWE) is associated with aneurysm growth or rupture. These studies assessed growth with manual 2D measurements or eyeballing, both of which are prone to interobserver variability. To minimize this variability, we assessed the association between AWE and semiautomatically quantified 3D morphologic changes in aneurysms during long-term follow-up. MATERIALS AND METHODS:We included patients with an unruptured intracranial aneurysm who had baseline MR aneurysm wall imaging and were followed with MR or CT angiography for ≥1 year. We used in-house-developed software to measure six 3D morphologic parameters on paired baseline and follow-up scans and determined changes with time. We compared the proportion of aneurysms showing morphologic change (modified z score, <-3.5 or >3.5) between aneurysms with and without AWE. The risk difference was calculated with 95% CI for each morphologic parameter. For parameters with a statistically significant change difference between aneurysms with and without AWE, we calculated ORs with 95% CI in a univariable logistic regression model and adjusted for aneurysm size in a bivariable model. RESULTS:Sixty-two patients with 72 unruptured intracranial aneurysms met the inclusion criteria. Twenty aneurysms (28%) in 18 patients showed AWE at baseline. The median follow-up was 5.8 years (interquartile range, 4.6-6.6 years). For the parameter curvedness, the proportion of aneurysms showing an increase was higher in aneurysms with AWE (6 of 20, 30%) than in aneurysms without AWE (2 of 52, 4%), with a risk difference of 26%; 95% CI, 9-49%. For the other 5 morphologic parameters, the proportion of aneurysms with morphologic change was comparable between aneurysms with and without AWE. In logistic regression analysis, AWE was associated with a curvedness increase (crude OR, 10.7; 95% CI, 2.2-78.9, adjusted OR, 6.1; 95% CI, 1.01-50.3). CONCLUSIONS:AWE was associated with aneurysm shape change during long-term follow-up, with an increase in 3D quantified curvedness that was independent of aneurysm size. This result reinforces previous findings that AWE is associated with aneurysm instability, in particular curvedness increase, and suggests that curvedness could be a suitable parameter to capture aneurysm instability. Future studies need to investigate whether an increase in this parameter predicts aneurysmal rupture.

OBJECTIVE:To evaluate the cost-effectiveness and cost-utility of adding ultra-early and short-term administration of tranexamic acid (TXA) to standard care in patients with subarachnoid hemorrhage (SAH). MATERIALS AND METHODS:An economic evaluation was performed alongside the ultra-early tranexamic acid after subarachnoid hemorrhage (ULTRA) trial. The main outcomes were the incremental cost-effectiveness ratio (ICER), expressed as costs per one-point increase in modified Rankin scale (mRS) score, and the incremental cost-utility ratio (ICUR), expressed as costs per quality-adjusted life-year (QALY). Cost-effectiveness acceptability curves (CEACs) were visualized with varying ICER cut-offs. Bootstrapping techniques and sensitivity analyses were performed to account for uncertainty. RESULTS:The ULTRA trial included 955 patients, with 480 assigned to the TXA group and 475 to the control group. The mean mRS score was 3.4 (95% CI: 3.2-3.5) in the TXA group and 3.2 (95% CI: 3.0-3.4) in the control group. The mean QALY was 0.26 (95% CI: 0.24-0.28) in the TXA group and 0.28 (95% CI: 0.26-0.30) in the control group. Mean costs were €62,180 (95% CI: 57,589-66,913) in the TXA group and €58,624 (95% CI: 53,693-63,955) in the control group. The probability of treatment with TXA being cost-effective ranged from 4% to 16% for mRS and from 8% to 16% for QALYs. CONCLUSIONS:Ultra-early and short-term administration of TXA to patients with SAH is not cost-effective. Therefore, we recommend against using TXA for this patient group. TRIAL REGISTRATION:Netherlands Trial Register: NTR3272. CLINICALTRIALS:gov identifier: NCT02684812.

IMPORTANCE Nontraumatic subarachnoid hemorrhage (SAH) represents the third most common stroke type with unique etiologies, risk factors, diagnostics, and treatments. Nevertheless, epidemiological studies often cluster SAH with other stroke types leaving its distinct burden estimates obscure. OBJECTIVE To estimate the worldwide burden of SAH. DESIGN, SETTING, AND PARTICIPANTS Based on the repeated cross-sectional Global Burden of Disease (GBD) 2021 study, the global burden of SAH in 1990 to 2021 was estimated. Moreover, the SAH burden was compared with other diseases, and its associations with 14 individual risk factors were investigated with available data in the GBD 2021 study. The GBD study included the burden estimates of nontraumatic SAH among all ages in 204 countries and territories between 1990 and 2021. EXPOSURES SAH and 14 modifiable risk factors. MAIN OUTCOMES AND MEASURES Absolute numbers and age-standardized rates with 95% uncertainty intervals (UIs) of SAH incidence, prevalence, mortality, and disability-adjusted life-years (DALYs) as well as risk factor-specific population attributable fractions (PAFs). RESULTS In 2021, the global age-standardized SAH incidence was 8.3 (95% UI, 7.3-9.5), prevalence was 92.2 (95% UI, 84.1-100.6), mortality was 4.2 (95% UI, 3.7-4.8), and DALY rate was 125.2 (95% UI, 110.5-142.6) per 100000 people. The highest burden estimates were found in Latin America, the Caribbean, Oceania, and high-income Asia Pacific. Although the absolute number of SAH cases increased, especially in regions with a low sociodemographic index, all age-standardized burden rates decreased between 1990 and 2021: the incidence by 28.8% (95% UI, 25.7%-31.6%), prevalence by 16.1% (95% UI, 14.8%-17.7%), mortality by 56.1% (95% UI, 40.7%-64.3%), and DALY rate by 54.6% (95% UI, 42.8%-61.9%). Of 300 diseases, SAH ranked as the 36th most common cause of death and 59th most common cause of DALY in the world. Of all worldwide SAH-related DALYs, 71.6% (95% UI, 63.8%-78.6%) were associated with the 14 modeled risk factors of which high systolic blood pressure (population attributable fraction [PAF]=51.6%; 95% UI, 38.0%-62.6%) and smoking (PAF=14.4%; 95% UI, 12.4%-16.5%) had the highest attribution. CONCLUSIONS AND RELEVANCE Although the global age-standardized burden rates of SAH more than halved over the last 3 decades, SAH remained one of the most common cardiovascular and neurological causes of death and disabilities in the world, with increasing absolute case numbers. These findings suggest evidence for the potential health benefits of proactive public health planning and resource allocation toward the prevention of SAH.

BACKGROUND:Survivors of aneurysmal subarachnoid hemorrhage (aSAH) often have cognitive impairment, which may be caused by long-term inflammation. We aimed to determine whether long-term neuroinflammation or microstructural brain damage is associated with cognitive impairment after aSAH. METHODS:In this prospective cohort study, we included patients >3 years after aSAH between 2020 and 2022. Patients underwent neuropsychological evaluation, translocator protein 18 kDA (TSPO) positron emission tomography (PET) imaging using [18F]DPA-714 to determine neuroinflammation, and brain diffusion kurtosis imaging (DKI) to determine microstructural damage. We compared TSPO PET binding potential, mean kurtosis (MK), kurtosis anisotropy (KA), axial kurtosis (AK), and radial kurtosis (RA) between groups and determined which metric was correlated with individual cognitive tests. RESULTS:We included 27 patients with aSAH; 14 with and 13 without cognitive impairment. Whole-brain TSPO binding potential was similar between groups (mean BPND: -0.046 [95% confidence interval (CI): -0.105; 0.013] vs -0.047 [95% CI -0.108; 0.014], p = 0.98) and there were no regional differences. Those with cognitive impairment had a lower whole-brain MK (mean MK 0.70 [95% CI: 0.69-0.72] vs 0.73 [95% CI: 0.72-0.74], p = 0.03) and whole-brain AK (mean AK 0.81 [95% CI: 0.78-0.83] vs 0.86 [0.84-0.87], p = 0.04). Left thalamic MK and AK were correlated with tests of verbal memory (r = 0.60-0.67, p < 0.01), while other correlation tests were non-significant. CONCLUSION:Our results do not support the hypothesis that long-term cognitive impairment after aSAH is caused by long-term neuroinflammation. Instead, microstructural damage may play a role.

About 3% of adults have an unruptured intracranial aneurysm and this prevalence can increase to 10% in high-risk groups. Aneurysms are not congenital, but develop throughout life. New evidence has established that genetic, anatomical, inflammatory, and modifiable risk factors interact in the formation, growth, and rupture of aneurysms. Genome-wide association studies have found an association with genetic risk variants in 17 loci. Furthermore, circle of Willis variations predispose to aneurysm formation and cluster within families. These variations, plus modifiable risk factors, such as hypertension and smoking, result in haemodynamic stress and inflammatory reactions in the vessel and aneurysm wall but, in people at high risk, aneurysms can also form in the absence of hypertension or smoking. These research advances provide knowledge bases for the individualised concepts of identifying individuals who can have an aneurysm or patients with aneurysms at increased risk of rupture, and for pharmacological treatments for patients who do not require immediate preventive repair.

Nontraumatic subarachnoid hemorrhage (SAH) represents the third most common stroke type with unique etiologies, risk factors, diagnostics, and treatments. Nevertheless, epidemiological studies often cluster SAH with other stroke types leaving its distinct burden estimates obscure. To estimate the worldwide burden of SAH. Based on the repeated cross-sectional Global Burden of Disease (GBD) 2021 study, the global burden of SAH in 1990 to 2021 was estimated. Moreover, the SAH burden was compared with other diseases, and its associations with 14 individual risk factors were investigated with available data in the GBD 2021 study. The GBD study included the burden estimates of nontraumatic SAH among all ages in 204 countries and territories between 1990 and 2021. SAH and 14 modifiable risk factors. Absolute numbers and age-standardized rates with 95% uncertainty intervals (UIs) of SAH incidence, prevalence, mortality, and disability-adjusted life-years (DALYs) as well as risk factor–specific population attributable fractions (PAFs). In 2021, the global age-standardized SAH incidence was 8.3 (95% UI, 7.3-9.5), prevalence was 92.2 (95% UI, 84.1-100.6), mortality was 4.2 (95% UI, 3.7-4.8), and DALY rate was 125.2 (95% UI, 110.5-142.6) per 100 000 people. The highest burden estimates were found in Latin America, the Caribbean, Oceania, and high-income Asia Pacific. Although the absolute number of SAH cases increased, especially in regions with a low sociodemographic index, all age-standardized burden rates decreased between 1990 and 2021: the incidence by 28.8% (95% UI, 25.7%-31.6%), prevalence by 16.1% (95% UI, 14.8%-17.7%), mortality by 56.1% (95% UI, 40.7%-64.3%), and DALY rate by 54.6% (95% UI, 42.8%-61.9%). Of 300 diseases, SAH ranked as the 36th most common cause of death and 59th most common cause of DALY in the world. Of all worldwide SAH-related DALYs, 71.6% (95% UI, 63.8%-78.6%) were associated with the 14 modeled risk factors of which high systolic blood pressure (population attributable fraction [PAF] = 51.6%; 95% UI, 38.0%-62.6%) and smoking (PAF = 14.4%; 95% UI, 12.4%-16.5%) had the highest attribution. Although the global age-standardized burden rates of SAH more than halved over the last 3 decades, SAH remained one of the most common cardiovascular and neurological causes of death and disabilities in the world, with increasing absolute case numbers. These findings suggest evidence for the potential health benefits of proactive public health planning and resource allocation toward the prevention of SAH.

OBJECTIVE:Wall calcification in unruptured intracranial aneurysms (UIAs) increases the risk of complications of microsurgical aneurysm treatment. Therefore, information on wall calcification is important in deciding on the indication and modality of preventive treatment. However, wall calcification is often not visible on MR angiography. The authors studied risk factors for aneurysm wall calcifications to identify patients who should undergo preprocedural CT imaging to detect wall calcifications. METHODS:From two international cohorts of patients with single or multiple UIAs, data were collected on age, sex, smoking status, hypertension, aneurysm location, aneurysm size, and morphological parameters associated with increased risk for rupture (i.e., at-risk morphology = aspect ratio > 1.6, size ratio > 3, presence of lobulations, and/or irregular shape). Logistic regression was used to calculate odds ratios (ORs) with corresponding 95% confidence intervals (CIs) to investigate risk factors for wall calcification. Using receiver operating characteristic analysis in one cohort, a size cutoff value was determined for ruling out aneurysm wall calcification, which was validated in the other cohort. RESULTS:Two hundred fifty-five patients with 306 UIAs were included. In univariable analyses, risk factors of aneurysm wall calcification were aneurysm size (OR 1.2, 95% CI 1.1-1.3), hypertension (OR 2.1, 95% CI 1.1-4.5), and at-risk morphology (OR 2.4, 95% CI 1.3-4.4). In multivariable analysis, independent risk factors for wall calcification were aneurysm size (OR 1.2, 95% CI 1.1-1.3) and hypertension (OR 2.8, 95% CI 1.2-6.6), but not at-risk morphology (OR 1.3, 95% CI 0.7-2.7). Aneurysm wall calcification could be ruled out in more than 90% of aneurysms smaller than 6 mm in both the derivation and validation cohorts. CONCLUSIONS:Aneurysm size and hypertension are independent risk factors of aneurysm wall calcification. The authors recommend preprocedural CT imaging in patients with a UIA ≥ 6 mm.

BACKGROUND AND OBJECTIVES:Inflammation is a key pathomechanism for growth and rupture of intracranial aneurysms. Anti-inflammatory mechanisms may reduce rupture of intracranial aneurysms and the incidence of aneurysmal subarachnoid hemorrhage (SAH). Ultraviolet (UV) radiation from sunlight exposure induces systemic anti-inflammatory responses through immunosuppressive mechanisms. We studied whether SAH incidence is associated with UV radiation.METHODS:Global SAH incidence, time trends, and regional differences from 32 countries were linked to UV radiation data from the Tropospheric Emission Monitoring Internet Service. Odds between low vs high UV exposure and SAH incidence were calculated. Correlation analysis was performed using R (R 4.1.2).RESULTS:SAH incidences ranged from 1.3 to 27 per 100 000 patient-years (p-y) and UV index from 1.76 to 11.27. The correlation coefficient (rho) between SAH incidence and UV index was -0.48 (P = .012). SAH incidence was highest in Japan (13.7-27.9 p-y) with an UV index 6.28. UV index was highest in Chile 11.27 with a lower SAH incidence (3.8-4.8 p-y). The lowest UV index 1.76 was seen in Iceland with higher SAH incidence (9.8 p-y).Within Europe, regions with higher UV indices reported lower SAH incidences (Northwest Europe: SAH incidence p-y 8.61/UV index 2.85; Southeast Europe: SAH incidence p-y 7.37/UV index 4.65) with a significant inverse correlation (rho = -0.68, P = .004) and not a significant correlation between non-European countries (rho = -0.43, P = .19). Low exposure of UV radiation in global regions predicted higher than median incidences of SAH with an odds ratio 5.13 (95% CIs 1.02-31.5).CONCLUSION:The incidence of SAH is inversely associated with UV radiation. Further studies should assess the actual UV exposure in relation to SAH incidence and potential biological explanations for the relation we found.

BACKGROUND:At least 60% of stroke, 40% of dementia and 35% of late-life depression (LLD) are attributable to modifiable risk factors, with great overlap due to shared pathophysiology. This study aims to systematically identify overlapping risk factors for these diseases and calculate their relative impact on a composite outcome. METHODS:A systematic literature review was performed in PubMed, Embase and PsycInfo, between January 2000 and September 2023. We included meta-analyses reporting effect sizes of modifiable risk factors on the incidence of stroke, dementia and/or LLD. The most relevant meta-analyses were selected, and disability-adjusted life year (DALY) weighted beta (β)-coefficients were calculated for a composite outcome. The β-coefficients were normalised to assess relative impact. RESULTS:Our search yielded 182 meta-analyses meeting the inclusion criteria, of which 59 were selected to calculate DALY-weighted risk factors for a composite outcome. Identified risk factors included alcohol (normalised β-coefficient highest category: -34), blood pressure (130), body mass index (70), fasting plasma glucose (94), total cholesterol (22), leisure time cognitive activity (-91), depressive symptoms (57), diet (51), hearing loss (60), kidney function (101), pain (42), physical activity (-56), purpose in life (-50), sleep (76), smoking (91), social engagement (53) and stress (55). CONCLUSIONS:This study identified overlapping modifiable risk factors and calculated the relative impact of these factors on the risk of a composite outcome of stroke, dementia and LLD. These findings could guide preventative strategies and serve as an empirical foundation for future development of tools that can empower people to reduce their risk of these diseases. PROSPERO REGISTRATION NUMBER:CRD42023476939.

The clinical evaluation and decision making associated with the management of unruptured intracranial aneurysms are complex. In the past 5 years, studies have evaluated the benefits of screening in people at high-risk, such as those with a family history of aneurysmal subarachnoid haemorrhage or unruptured intracranial aneurysms, people with genetic or other disorders associated with intracranial aneurysms, and people who smoke and have hypertension. If an aneurysm is detected during screening or incidentally, prediction models now allow for estimating the risk of complications from preventive aneurysm occlusion. Other prediction models can estimate the risk of aneurysm growth and the risk of rupture after growth. Thus, screening and management strategies are shifting towards a personalised approach. Uncertainties remain regarding the value of screening in some individuals, the long-term benefits of preventive occlusion, and the effectiveness of medical treatment strategies to prevent aneurysm growth and rupture.

Patients who have a cerebral cavernous malformation that was identified because of a seizure or a focal deficit are at risk of developing epilepsy or of new or worsening signs and symptoms from further bleeding of the malformation. In many countries, options for microsurgical removal or radiosurgical treatment are available in standard practice. These approaches aim to prevent new bleeding but carry a risk of immediate or delayed complications. Observational studies have not convincingly shown the superiority of surgical treatment compared with standard medical care. Therefore, patients and their medical team are left with a difficult decision—whether or not to undergo surgery. Medical management and surgery versus medical management alone for symptomatic cerebral cavernous malformation (CARE): a feasibility study and randomised, open, pragmatic, pilot phase trialThis pilot phase trial exceeded its recruitment target, but a definitive trial will require extensive international engagement. Full-Text PDF Open Access