Migraine with aura
Often the earliest symptom — appearing in the 20s or 30s. About 30–40% of CADASIL patients experience migraine with aura. Auras may be visual, sensory, or aphasic, and are sometimes prolonged (hours rather than minutes), atypical, or hemiplegic.
Rarely, a migraine attack can be followed by an encephalopathic episode — hours to days of fever, seizures, altered consciousness, or severe migraine-like symptoms. These are frightening but generally reversible, and always warrant emergency assessment. More about encephalopathic episodes →
Onset: 20s–30s · Frequency: 30–40% of patients
Stroke & TIA
Recurrent small, deep strokes (called lacunar strokes) and TIAs — sometimes called "mini-strokes," where stroke-like symptoms come on and then resolve — are the clinical hallmark. These most often begin between the ages of 40 and 70, and they typically occur in people without classical vascular risk factors, which is part of why diagnosis is often delayed.
In plain terms, a CADASIL stroke often looks like sudden one-sided weakness (arm, leg, or face), slurred speech, or a brief episode of numbness or vision change. Individual events are usually mild, and many people recover most or all of their function. But the cumulative effect of repeated strokes over years is what drives the disease's long-term impact — which is why early diagnosis and vascular risk-factor control matter so much.
Onset: 40s–70s · Frequency: 60–85% over a lifetime
Cognitive impairment
When cognitive change occurs in CADASIL, it commonly affects attention, processing speed, and executive function first. Memory tends to be relatively spared early on. Some people experience stepwise change rather than smooth decline; others report only subtle changes for many years, or none at all.
Age most commonly reported: 50s–70s · Frequency: Reported in a substantial share of people with CADASIL; not universal
Mood disturbance & apathy
Depression and apathy affect ~30% of patients and may precede other symptoms. Apathy in CADASIL is a distinct clinical feature, not just "low mood" — it reflects disconnection of frontal–subcortical circuits and often goes unrecognized.
Onset: Any age · Frequency: ~30%
Gait disturbance
Later in life, some people with CADASIL develop a small-stepped, magnetic gait, imbalance, or pseudobulbar features (emotional incontinence, dysphagia). These have been linked to cumulative deep white-matter and basal-ganglia change. Not everyone develops gait problems.
Age most commonly reported: 60s+ · Frequency: More commonly seen with advanced disease; not universal
A telling family history
The pattern is autosomal dominant — strokes, "early dementia," migraines, or psychiatric illness across multiple generations. Some families have already been told their relatives had MS, a "weak vessel," or unexplained early decline.
Inheritance: 50% per child · Penetrance: Near-complete, variable expressivity
