Decreased microvascular claudin-5 levels in cerebral amyloid angiopathy associated with intracerebral haemorrhage

Decreased microvascular levels of claudin-5 in the occipital and temporal lobe of patients with cerebral amyloid angiopathy are associated with intracerebral haemorrhage.

Anakinra in cerebral haemorrhage to target secondary injury resulting from neuroinflammation (ACTION): Study protocol of a phase II randomised clinical trial

BACKGROUND

Inflammation plays a vital role in the development of secondary brain injury after spontaneous intracerebral haemorrhage (ICH). Interleukin-1 beta is an early pro-inflammatory cytokine and a potential therapeutic target.

AIM

To determine the effect of treatment with recombinant human interleukin-1 receptor antagonist anakinra on perihematomal oedema (PHO) formation in patients with spontaneous ICH compared to standard medical management, and investigate whether this effect is dose-dependent.

METHODS

ACTION is a phase-II, prospective, randomised, three-armed (1:1:1) trial with open-label treatment and blinded end-point assessment (PROBE) at three hospitals in The Netherlands. We will include 75 patients with a supratentorial spontaneous ICH admitted within 8 h after symptom onset. Participants will receive anakinra in a high dose (loading dose 500 mg intravenously, followed by infusion with 2 mg/kg/h over 72 h; n = 25) or in a low dose (loading dose 100 mg subcutaneously, followed by 100 mg subcutaneous twice daily for 72 h; n = 25), plus standard care. The control group (n = 25) will receive standard medical management.

OUTCOMES

Primary outcome is PHO, measured as oedema extension distance on MRI at day 7 ± 1. Secondary outcomes include the safety profile of anakinra, the effect of anakinra on serum inflammation markers, MRI measures of blood brain barrier integrity, and functional outcome at 90 ± 7 days.

DISCUSSION

The ACTION trial will provide insight into whether targeting interleukin-1 beta in the early time window after ICH onset could ameliorate secondary brain injury. This may contribute to the development of new treatment options to improve clinical outcome after ICH.

The association between blood pressure variability and perihematomal edema after spontaneous intracerebral hemorrhage

Background

Perihematomal edema (PHE) after spontaneous intracerebral hemorrhage (sICH) is associated with clinical deterioration, but the etiology of PHE development is only partly understood.

Aims

We aimed to investigate the association between systemic blood pressure (BP) variability (BPV) and formation of PHE.

Methods

From a multicenter prospective observational study, we selected patients with sICH who underwent 3T brain MRI within 21 days after sICH, and had at least 5 BP measurements available in the first week after sICH. Primary outcome was the association between coefficient of variation (CV) of systolic BP (SBP) and edema extension distance (EED) using multivariable linear regression, adjusting for age, sex, ICH volume and timing of the MRI. In addition, we investigated the associations of mean SBP, mean arterial pressure (MAP), their CVs with EED and absolute and relative PHE volume.

Results

We included 92 patients (mean age 64 years; 74% men; median ICH volume 16.8 mL (IQR 6.6–36.0), median PHE volume 22.5 mL (IQR 10.2–41.4). Median time between symptom onset and MRI was 6 days (IQR 4–11), median number of BP measurements was 25 (IQR 18–30). Log-transformed CV of SBP was not associated with EED (B = 0.050, 95%-CI −0.186 to 0.286, p = 0.673). Furthermore, we found no association between mean SBP, mean and CV of MAP and EED, nor between mean SBP, mean MAP or their CVs and absolute or relative PHE.

Discussion

Our results do not support a contributing role for BPV on PHE, suggesting mechanisms other than hydrostatic pressure such as inflammatory processes, may play a more important role.

Cerebral small vessel disease and perihematomal edema formation in spontaneous intracerebral hemorrhage

Objective

Blood-brain barrier (BBB) dysfunction is implicated in the pathophysiology of cerebral small vessel disease (cSVD)-related intracerebral hemorrhage (ICH). The formation of perihematomal edema (PHE) is presumed to reflect acute BBB permeability following ICH. We aimed to assess the association between cSVD burden and PHE formation in patients with spontaneous ICH.

Methods

We selected patients with spontaneous ICH who underwent 3T MRI imaging within 21 days after symptom onset from a prospective observational multicenter cohort study. We rated markers of cSVD (white matter hyperintensities, enlarged perivascular spaces, lacunes and cerebral microbleeds) and calculated the composite score as a measure of the total cSVD burden. Perihematomal edema formation was measured using the edema extension distance (EED). We assessed the association between the cSVD burden and the EED using a multivariable linear regression model adjusting for age, (log-transformed) ICH volume, ICH location (lobar vs. non-lobar), and interval between symptom onset and MRI.

Results

We included 85 patients (mean age 63.5 years, 75.3% male). Median interval between symptom onset and MRI imaging was 6 days (IQR 1–19). Median ICH volume was 17.0 mL (IQR 1.4–88.6), and mean EED was 0.54 cm (SD 0.17). We found no association between the total cSVD burden and EED (B = −0.003, 95% CI −0.003–0.03, p = 0.83), nor for any of the individual radiological cSVD markers.

Conclusion

We found no association between the cSVD burden and PHE formation. This implies that mechanisms other than BBB dysfunction are involved in the pathophysiology of PHE.

Diffusion-Weighted Lesions After Intracerebral Hemorrhage: Associated MRI Findings

The current study aimed to investigate whether diffusion-weighted imaging-positive (DWI+) lesions after acute intracerebral hemorrhage (ICH) are associated with underlying small vessel disease (SVD) or linked to the acute ICH. We included patients ≥18 years with spontaneous ICH confirmed on neuroimaging and performed 3T MRIs after a median of 11 days (interquartile range [IQR] 6–43). DWI+ lesions were assessed in relation to the hematoma (perihematomal vs. distant and ipsilateral vs. contralateral). Differences in clinical characteristics, ICH characteristics, and MRI markers of SVD between participants with or without DWI+ lesions were investigated using non-parametric tests. We observed 54 DWI+ lesions in 30 (22%) of the 138 patients (median age [IQR] 65 [55–73] years; 71% men, 59 lobar ICH) with available DWI images. We found DWI+ lesions ipsilateral (54%) and contralateral (46%) to the ICH, and 5 (9%) DWI+ lesions were located in the immediate perihematomal region. DWI+ lesion presence was associated with probable CAA diagnosis (38 vs. 15%, p = 0.01) and larger ICH volumes (37 [8–47] vs. 12 [6–24] ml, p = 0.01), but not with imaging features of SVD. Our findings suggest that DWI+ lesions after ICH are a feature of both the underlying SVD and ICH-related mechanisms.

Trigger Factors for Spontaneous Intracerebral Hemorrhage: A Case-Crossover Study

BACKGROUND AND PURPOSE

Whether certain activities can trigger spontaneous intracerebral hemorrhage (ICH) remains unknown. Insights into factors that trigger vessel rupture resulting in ICH improves knowledge on the pathophysiology of ICH. We assessed potential trigger factors and their risk for ICH onset.

METHODS

We included consecutive patients diagnosed with ICH between July 1, 2013, and December 31, 2019. We interviewed patients on their exposure to 12 potential trigger factors (eg, Valsalva maneuvers) in the (hazard) period soon before onset of ICH and their normal exposure to these trigger factors in the year before the ICH. We used the case-crossover design to calculate relative risks (RR) for potential trigger factors.

RESULTS

We interviewed 149 patients (mean age 64, 66% male) with ICH. Sixty-seven (45%) had a lobar hemorrhage, 60 (40%) had a deep hemorrhage, 19 (13%) had a cerebellar hemorrhage, and 3 (2%) had an intraventricular hemorrhage. For ICH in general, there was an increased risk within an hour after caffeine consumption (RR=2.5 [95% CI=1.8-3.6]), within an hour after coffee consumption alone (RR=4.8 [95% CI=3.3-6.9]), within an hour after lifting >25 kg (RR=6.6 [95% CI=2.2-19.9]), within an hour after minor head trauma (RR=10.1 [95% CI=1.7-60.2]), within an hour after sexual activity (RR=30.4 [95% CI=16.8-55.0]), within an hour after straining for defecation (RR=37.6 [95% CI=22.4-63.4]), and within an hour after vigorous exercise (RR=21.8 [95% CI=12.6-37.8]). Within 24 hours after flu-like disease or fever, the risk for ICH was also increased (RR=50.7 [95% CI=27.1-95.1]). Within an hour after Valsalva maneuvers, the RR for deep ICH was 3.5 (95% CI=1.7-6.9) and for lobar ICH the RR was 2.0 (95% CI=0.9-4.2).

CONCLUSIONS

We identified one infection and several blood pressure related trigger factors for ICH onset, providing new insights into the pathophysiology of vessel rupture resulting in ICH.

Cerebellar Superficial Siderosis in Cerebral Amyloid Angiopathy

BACKGROUND AND PURPOSE

Although evidence accumulates that the cerebellum is involved in cerebral amyloid angiopathy (CAA), cerebellar superficial siderosis is not considered to be a disease marker. The objective of this study is to investigate cerebellar superficial siderosis frequency and its relation to hemorrhagic magnetic resonance imaging markers in patients with sporadic and Dutch-type hereditary CAA and patients with deep perforating arteriopathy-related intracerebral hemorrhage.

METHODS

We recruited patients from 3 prospective 3 Tesla magnetic resonance imaging studies and scored siderosis and hemorrhages. Cerebellar siderosis was identified as hypointense linear signal loss (black) on susceptibility-weighted or T2*-weighted magnetic resonance imaging which follows at least one folia of the cerebellar cortex (including the vermis).

RESULTS

We included 50 subjects with Dutch-type hereditary CAA, (mean age 50 years), 45 with sporadic CAA (mean age 72 years), and 43 patients with deep perforating arteriopathy-related intracerebral hemorrhage (mean age 54 years). Cerebellar superficial siderosis was present in 5 out of 50 (10% [95% CI, 2-18]) patients with Dutch-type hereditary CAA, 4/45 (9% [95% CI, 1-17]) patients with sporadic CAA, and 0 out of 43 (0% [95% CI, 0-8]) patients with deep perforating arteriopathy-related intracerebral hemorrhage. Patients with cerebellar superficial siderosis had more supratentorial lobar (median number 9 versus 2, relative risk, 2.9 [95% CI, 2.5-3.4]) and superficial cerebellar macrobleeds (median number 2 versus 0, relative risk, 20.3 [95% CI, 8.6-47.6]) compared with patients without the marker. The frequency of cortical superficial siderosis and superficial cerebellar microbleeds was comparable.

CONCLUSIONS

We conclude that cerebellar superficial siderosis might be a novel marker for CAA.

Location-specific risk factors for intracerebral hemorrhage: Systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of studies reporting on risk factors according to location of the intracerebral hemorrhage.

METHODS

We searched PubMed and Embase for cohort and case-control studies reporting ≥100 patients with spontaneous intracerebral hemorrhage that specified the location of the hematoma and reported associations with risk factors published until June 27, 2019. Two authors independently extracted data on risk factors. Estimates were pooled with the generic variance-based random-effects method.

RESULTS

After screening 10,013 articles, we included 42 studies totaling 26,174 patients with intracerebral hemorrhage (9,141 lobar and 17,033 nonlobar). Risk factors for nonlobar intracerebral hemorrhage were hypertension (risk ratio [RR] 4.25, 95% confidence interval [CI] 3.05-5.91, I ² = 92%), diabetes mellitus (RR 1.35, 95% CI 1.11-1.64, I ² = 37%), male sex (RR 1.63, 95% CI 1.25-2.14, I ² = 61%), alcohol overuse (RR 1.48, 95% CI 1.21-1.81, I ² = 19%), underweight (RR 2.12, 95% CI 1.12-4.01, I ² = 31%), and being a Black (RR 2.83, 95% CI 1.02-7.84, I ² = 96%) or Hispanic (RR 2.95, 95% CI 1.69-5.14, I ² = 71%) participant compared with being a White participant. Hypertension, but not any of the other risk factors, was also a risk factor for lobar intracerebral hemorrhage (RR 1.83, 95% CI 1.39-2.42, I ² = 76%). Smoking, hypercholesterolemia, and obesity were associated with neither nonlobar nor lobar intracerebral hemorrhage.

CONCLUSIONS

Hypertension is a risk factor for both nonlobar and lobar intracerebral hemorrhage, although with double the effect for nonlobar intracerebral hemorrhage. Diabetes mellitus, male sex, alcohol overuse, underweight, and being a Black or Hispanic person are risk factors for nonlobar intracerebral hemorrhage only. Hence, the term hypertensive intracerebral hemorrhage for nonlobar intracerebral hemorrhage is not appropriate.

Disturbed balance in the expression of MMP9 and TIMP3 in cerebral amyloid angiopathy-related intracerebral haemorrhage

Cerebral amyloid angiopathy (CAA) is characterized by the deposition of the amyloid β (Aβ) protein in the cerebral vasculature and poses a major risk factor for the development of intracerebral haemorrhages (ICH). However, only a minority of patients with CAA develops ICH (CAA-ICH), and to date it is unclear which mechanisms determine why some patients with CAA are more susceptible to haemorrhage than others. We hypothesized that an imbalance between matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) contributes to vessel wall weakening. MMP9 plays a role in the degradation of various components of the extracellular matrix as well as of Aβ and increased MMP9 expression has been previously associated with CAA. TIMP3 is an inhibitor of MMP9 and increased TIMP3 expression in cerebral vessels has also been associated with CAA. In this study, we investigated the expression of MMP9 and TIMP3 in occipital brain tissue of CAA-ICH cases (n = 11) by immunohistochemistry and compared this to the expression in brain tissue of CAA cases without ICH (CAA-non-haemorrhagic, CAA-NH, n = 18). We showed that MMP9 expression is increased in CAA-ICH cases compared to CAA-NH cases. Furthermore, we showed that TIMP3 expression is increased in CAA cases compared to controls without CAA, and that TIMP3 expression is reduced in a subset of CAA-ICH cases compared to CAA-NH cases. In conclusion, in patients with CAA, a disbalance in cerebrovascular MMP9 and TIMP3 expression is associated with CAA-related ICH.

Risk Factors for Lobar and Non-Lobar Intracerebral Hemorrhage in Patients with Vascular Disease

INTRODUCTION

Lobar and non-lobar non-traumatic intracerebral hemorrhage (ICH) are presumably caused by different types of small vessel diseases. The aim of this study was to assess risk factors for ICH according to location.

METHODS

In two large prospective studies, SMART (n = 9088) and ESPRIT (n = 2625), including patients with manifest cardiovascular, cerebrovascular or peripheral artery disease or with vascular risk factors, we investigated potential risk factors for ICH during follow-up according to lobar or non-lobar location by Cox proportional hazards analyses.

RESULTS

During 65,156 patient years of follow up 19 patients had lobar ICH (incidence rate 29, 95% CI 19-42 per 100,000 person-years) and 24 non-lobar ICH (incidence rate 37, 95% CI 26-51 per 100,000 person-years). Age significantly increased the risk of lobar ICH (HR per 10 years increase 1.90; 95% CI 1.17-3.10) in the multivariable analysis, but not of non-lobar hemorrhage. Anticoagulant medication (HR 3.49; 95% CI 1.20-10.2) and male sex (HR 3.79; 95% CI 1.13-12.8) increased the risk of non-lobar but not lobar ICH.

CONCLUSION

This study shows an elevated risk of future ICH in patients with manifestations of, or risk factors for, cardiovascular, cerebrovascular or peripheral artery disease. Our data suggest that risk factors for ICH vary according to location, supporting the hypothesis of a differential pathophysiology of lobar and non-lobar ICH.