What are the risk factors of Central Retinal Vein Occlusion (CRVO) and Branch Retinal Vein Occlusion (BRVO)?

From the Guidelines

Central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO) are primarily associated with risk factors such as systemic arterial hypertension, arteriosclerosis, and diabetes, as highlighted in the most recent guidelines 1.

Key Risk Factors

• Age: The risk of CRVO and BRVO increases with advancing age, with most cases occurring in individuals over 40 years old 1.
• Hypertension: Systemic arterial hypertension is a major risk factor for both CRVO and BRVO, as it can lead to vascular damage and increase the risk of occlusion 1.
• Diabetes: Diabetes mellitus is another significant risk factor, as it can cause vascular changes and increase the risk of retinal vein occlusion 1.
• Arteriosclerosis: The hardening of arteries can also contribute to the risk of CRVO and BRVO by reducing blood flow to the retina 1.

Additional Risk Factors

• Glaucoma: Open-angle glaucoma is strongly associated with CRVO due to increased intraocular pressure affecting retinal venous outflow 1.
• Hypercoagulable states: Conditions such as protein C or S deficiency, antiphospholipid syndrome, and hyperhomocysteinemia can increase the risk of CRVO and BRVO 1.
• Inflammatory conditions: Vasculitis and other inflammatory conditions can also increase the risk of retinal vein occlusion 1.
• Anatomical factors: Arteriovenous crossing compression is a significant risk factor for BRVO, as it can create turbulent blood flow and predispose to occlusion 1.

Importance of Risk Factor Management

Managing these risk factors is crucial for preventing CRVO and BRVO, as well as reducing the risk of vision loss and other complications 1. By optimizing systemic blood pressure, controlling diabetes, and managing glaucoma and ocular hypertension, individuals can reduce their risk of developing these conditions. Additionally, increasing awareness of the higher risk of cardiovascular and stroke complications in patients with RVO can help guide treatment and management strategies 1.

From the Research

Risk Factors for CRVO and BRVO

The risk factors for central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO) can be categorized into several groups, including:

• Systemic conditions:
  • Hypertension 2, 3, 4
  • Diabetes mellitus 2, 3
  • Hyperlipidemia 2
  • Vascular cerebral stroke 2
  • Blood hyperviscosity 2
  • Thrombophilia 2
• Socioeconomic and demographic factors:
  • Advancing age 2
  • Socioeconomic status 2
  • American blacks are more often diagnosed with RVO than non-Hispanic whites 2
  • Females are at lower risk than men 2
• Ophthalmic risk factors:
  • Ocular hypertension 2, 4
  • Glaucoma 2, 3
  • Higher ocular perfusion pressure 2
  • Changes in the retinal arteries 2
• Other risk factors:
  • Cigarette smoking 2
  • Systemic inflammatory conditions like vasculitis and Behcet disease 2
  • Congenital thrombophilic diseases like factor V Leiden mutation, hyperhomocysteinemia and anticardiolipin antibodies 2
  • Metabolic syndrome (hypertension, diabetes mellitus, and hyperlipidemia) 2
  • Cardiovascular disease, electrocardiographic abnormalities, history of treatment of diabetes mellitus, higher blood glucose levels, lower albumin-globulin ratios, and higher alpha-globulin levels 3
  • Ischemia 5

Comparison of Risk Factors between CRVO and BRVO

Some studies have compared the risk factors associated with CRVO and BRVO, finding that:

• Hypertension and hyperopia are more prevalent in BRVO than in CRVO 4
• Elevated intraocular pressure, elevated erythrocyte sedimentation rate (ESR), and a positive tuberculin skin test are more prevalent in CRVO than in BRVO 4
• Systemic hypertension and hyperopia are the main risk factors for BRVO, while the causes of ESR elevation are more significant risk factors for CRVO 4