Causes of Stroke in Young Individuals
Young stroke is primarily caused by vascular abnormalities, cardiac disorders, hypercoagulable states, and modifiable risk factors that differ significantly from those in older populations. 1
Major Categories of Young Stroke Causes
Vascular Abnormalities (30-40% of cases)
- Cervicocephalic arterial dissections - leading cause in many young stroke cohorts 1
- Moyamoya disease and syndrome - progressive vasculopathy of intracranial vessels 1
- Fibromuscular dysplasia (FMD) - non-inflammatory arteriopathy 1
- Vasculitis - inflammatory vessel disease 1
- Transient cerebral arteriopathy - often post-infectious 1
- Post-varicella angiopathy - delayed cerebrovascular complication 1
Cardiac Sources (15-30% of cases)
- Patent foramen ovale - particularly important in cryptogenic stroke 1
- Congenital heart disease - significant risk factor 1
- Cardioembolism - from various cardiac abnormalities 1
Hematologic/Hypercoagulable States
- Inherited thrombophilias:
- Factor V Leiden mutation
- Prothrombin G20210A mutation
- Protein C, S, or antithrombin III deficiency 1
- Acquired hypercoagulable states:
- Malignancy
- Pregnancy and postpartum period
- Oral contraceptives
- Nephrotic syndrome 1
Genetic Disorders
- CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) - NOTCH3 gene mutation 1
- Fabry disease - α-galactosidase-A deficiency 1
- Mitochondrial disorders - MELAS, MERRF 1
- Connective tissue disorders - Ehlers-Danlos syndrome, Marfan syndrome 1
Modifiable Risk Factors (Increasingly Common)
- Smoking - present in 55.5% of young stroke patients 2
- Physical inactivity - 48.2% prevalence 2
- Hypertension - 46.6% prevalence 2
- Dyslipidemia - 34.9% prevalence 2
- Obesity - 22.3% prevalence 2
- Substance abuse - particularly cocaine, amphetamines 3
- High-risk alcohol consumption - 33% prevalence, more common in men 2
Other Important Factors
- Low birth weight - doubles stroke risk by age 50 1
- Race/ethnicity - higher incidence in Black and some Hispanic/Latino populations 1
- Migraine - particularly with aura, more common in women (26.5%) 4, 2
- Homocysteinemia - often related to MTHFR mutations 5
Age-Specific Considerations
Very Young Adults (18-35 years)
- Genetic disorders and congenital heart disease more prominent
- Cervicocephalic dissection often related to trauma
- Hypercoagulable states particularly important in women (oral contraceptives, pregnancy)
- Lower prevalence of traditional vascular risk factors 4
Middle-Aged Young Adults (35-50 years)
- Increasing prevalence of traditional risk factors
- Combination of modifiable risk factors and genetic predisposition
- Higher rates of arterial hypertension, dyslipidemia, and diabetes 2
Clinical Implications
Diagnostic approach must be comprehensive - up to 30% of young strokes remain cryptogenic despite thorough evaluation 1
Genetic testing considerations:
Risk of recurrence:
- 6-14% clinical recurrence rate in young stroke patients
- Higher with vascular abnormalities, especially moyamoya syndrome
- Presence of genetic thrombophilia increases recurrence risk 1
Prevention strategies:
- Aggressive modification of lifestyle factors is essential
- Particular attention to smoking cessation, physical activity, and blood pressure control
- Standard multivitamin with B6, B12, and folate reasonable for hyperhomocysteinemia 1
Common Pitfalls in Young Stroke Management
- Delayed diagnosis due to low clinical suspicion in young patients 3
- Incomplete workup failing to identify rare causes
- Overemphasis on single risk factors when multiple factors often coexist
- Underestimating traditional risk factors in young patients
- Focusing only on MTHFR mutations without checking homocysteine levels or other thrombophilias 5
The rising incidence of stroke in young adults, particularly with increasing prevalence of modifiable risk factors, highlights the critical importance of comprehensive evaluation and aggressive prevention strategies in this population.