What are the causes of lobar intracerebral hemorrhage (ICH) in the elderly?

From the Guidelines

Lobar intracerebral hemorrhage (ICH) in the elderly is primarily caused by cerebral amyloid angiopathy (CAA) and, to a lesser extent, arteriolosclerosis.

Causes of Lobar ICH

• Cerebral Amyloid Angiopathy (CAA): This is a common age-related pathology, characterized by the deposition of β-amyloid peptide in the walls of arterioles and capillaries in the leptomeninges, cerebral cortex, and cerebellar hemispheres (lobar territories) 1.
• Arteriolosclerosis: Also known as lipohyalinosis, this condition is detected as concentric hyalinized vascular wall thickening favoring the penetrating arterioles of the basal ganglia, thalamus, brainstem, and deep cerebellar nuclei (deep territories), but can also contribute to lobar ICH 1.

Risk Factors

• Age: Advanced age is a significant risk factor for both CAA and arteriolosclerosis, with the prevalence of these conditions increasing with age 1.
• Apolipoprotein E genotypes: The presence of the ε2 or ε4 alleles increases the risk of CAA and, consequently, lobar ICH 1.
• Hypertension: High blood pressure is a major risk factor for arteriolosclerosis and can contribute to the development of lobar ICH 1.
• Antithrombotic medications: The use of anticoagulant agents, such as warfarin, can increase the risk of ICH, particularly in the elderly 1.

Management and Prevention

• Blood pressure control: Managing hypertension is crucial in preventing ICH recurrence, with a target blood pressure of less than 140/90 mmHg (or <130/80 mmHg in the presence of diabetes or chronic kidney disease) 1.
• Avoidance of anticoagulation: In patients with a history of lobar ICH, particularly those with CAA, the risks of anticoagulation may outweigh the benefits, and alternative strategies, such as antiplatelet therapy, may be considered 1.

From the Research

Causes of Lobar Intracerebral Hemorrhage (ICH) in the Elderly

• Cerebral amyloid angiopathy (CAA) is a significant cause of lobar intracerebral hemorrhage (ICH) in the elderly, accounting for 12%-15% of cases 2.
• CAA-associated hemorrhages are most often solitary, but the natural history often progresses to include multifocal and recurrent hemorrhages 2.
• The deposition of beta-amyloid (Aβ) protein in cerebrovascular vessels is the primary cause of CAA, which is frequently found in patients with Alzheimer's disease (AD) 3.
• Specific apolipoproteins (Apo), such as ApoE and ApoJ, have been associated with Aβ fibrillization and clearance from the brain, and may play a role in the development of CAA 3.
• Other factors, such as genetic polymorphisms, may also contribute to the development of CAA and increase the risk of lobar ICH in the elderly 4.

Risk Factors for Lobar ICH in the Elderly

• Increasing age is a significant risk factor for lobar ICH, with the majority of cases occurring in patients over 70 years old 5.
• The presence of CAA, as diagnosed by the Boston Criteria, is a strong predictor of lobar ICH in the elderly 5.
• The APOE genotype, particularly the APOEε2 allele, may also increase the risk of lobar ICH in patients with CAA 3.
• Other risk factors, such as hypertension and anticoagulation therapy, may also contribute to the development of lobar ICH in the elderly 6.

Clinical Presentation and Diagnosis

• Lobar ICH in the elderly often presents with sudden onset of neurological symptoms, such as headache, confusion, and weakness 2.
• Imaging studies, such as MRI, may show evidence of CAA, including cortical superficial siderosis (cSS) and cortical subarachnoid hemorrhage (cSAH) 6.
• The diagnosis of CAA is often made based on a combination of clinical and imaging findings, as well as pathological evidence of amyloid angiopathy 5.