In the Netherlands, ICH incidence, case fatality, and mortality rates have declined significantly in men and women younger than 75 years but remained stable in patients 75 years and older. The observed time trends may be explained by better prevention and treatment during the previous 2 decades of which the elderly do not seem to benefit.

Objective:To conduct a systematic review and meta-analysis of studies reporting on risk factors according to the location of the intracerebral hemorrhage.Methods:We searched PubMed and Embase for cohort and case-control studies reporting on ≥100 patients with spontaneous intracerebral hemorrhage, that specified the location of the hematoma and reported associations with risk factors published until June 27th 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 non-lobar). Risk factors for non-lobar intracerebral hemorrhage were hypertension (risk ratio 4.25, 95% confidence interval 3.05-5.91, I2=92%), diabetes (RR 1.35, 1.11-1.64, I2=37% ), male sex (RR 1.63, 1.25-2.14, I2=61%), alcohol overuse (RR 1.48, 1.21-1.81, I2=19%), underweight (RR 2.12, 1.12-4.01, I2=31%), and being black (RR 2.19, 1.21-3.96, I2=96%) or Hispanic (RR 2.13,0.94-4.81, I2=71%) in comparison with being white. Hypertension, but not any of the other risk factors, was also a risk factor for lobar intracerebral hemorrhage (RR 1.83, 1.39-2.42, I2=76%). Smoking, hypercholesterolemia and obesity were associated with neither non-lobar nor lobar intracerebral hemorrhage.Conclusions:Hypertension is a risk factor for both non-lobar and lobar intracerebral hemorrhage, although with double the effect for non-lobar intracerebral hemorrhage. Diabetes, male sex, alcohol overuse, underweight, and being black or Hispanic are risk factors for non-lobar intracerebral hemorrhage only. Hence, the term “hypertensive intracerebral hemorrhage” for non-lobar intracerebral hemorrhage is not appropriate.

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.

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.

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IntroductionLobar 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.MethodsIn 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.ResultsDuring 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.ConclusionThis 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.

Disruption of the blood–brain barrier (BBB) might play a role in the pathophysiology of cerebral small vessel disease-related ICH. The aim of this study was to assess presence and extent of contrast agent leakage distant from the hematoma as a marker of BBB disruption in patients with spontaneous ICH. We prospectively performed 7 tesla MRI in adult patients with spontaneous ICH and assessed contrast leakage distant from the hematoma on 3D FLAIR images. Thirty-one patients were included (mean age 60 years, 29% women). Median time between ICH and MRI was 20 days (IQR 9–67 days). Seventeen patients (54%; seven lobar, nine deep, one infratentorial ICH) had contrast leakage, located cortical in 16 and cortical and deep in one patient. Patients with contrast leakage more often had lobar cerebral microbleeds (CMBs; 77%) than those without (36%; RR 2.5, 95% CI 1.1–5.7) and a higher number of lobar CMBs (patients with contrast leakage: median 2, IQR 1–8 versus those without: median 0, IQR 0–2; p = 0.02). This study shows that contrast leakage distant from the hematoma is common in days to weeks after spontaneous ICH. It is located predominantly cortical and related to lobar CMBs and therefore possibly to 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.