Stroke

A stroke occurs when the blood supply to part of the brain is suddenly cut off, either by a blocked blood vessel (ischaemic stroke — about 85% of cases) or a burst blood vessel (haemorrhagic stroke). Without blood and oxygen, brain cells begin to die within minutes. Stroke is a medical emergency: every minute of delayed treatment results in the loss of approximately 1.9 million brain cells. Nigeria has one of the highest stroke rates in the world, driven by the high prevalence of uncontrolled hypertension. Stroke is a leading cause of death and long-term disability, but up to 80% of strokes are preventable.

The hallmark of stroke is sudden onset of neurological symptoms. Use the FAST acronym to identify a stroke: F — Face drooping: Is one side of the face drooping or numb? Ask the person to smile — is the smile uneven? A — Arm weakness: Is one arm weak or numb? Ask them to raise both arms — does one drift downward? S — Speech difficulty: Is speech slurred, garbled, or impossible? Can the person repeat a simple sentence correctly? T — Time to call for help: If any of these signs are present, seek emergency care immediately. Other stroke symptoms: • Sudden severe headache with no known cause (often described as "the worst headache of my life"): common in haemorrhagic stroke • Sudden vision changes in one or both eyes • Sudden loss of balance, coordination, or dizziness • Sudden confusion or trouble understanding what others are saying • Sudden numbness in the face, arm, or leg, especially on one side of the body

Ischaemic stroke (blocked blood vessel — 85% of cases): • Blood clot forms in a narrowed artery supplying the brain (thrombotic stroke) • Blood clot forms elsewhere (e.g., heart in atrial fibrillation) and travels to block a brain artery (embolic stroke) • Narrowing of blood vessels due to atherosclerosis (plaque build-up) Haemorrhagic stroke (burst blood vessel — 15% of cases): • Intracerebral haemorrhage: a vessel inside the brain bursts, most commonly due to severely uncontrolled hypertension • Subarachnoid haemorrhage: bleeding into the space surrounding the brain, usually from a ruptured aneurysm The underlying driver in the majority of Nigerian stroke cases is chronic, poorly treated hypertension, which damages and weakens blood vessel walls over time.

Non-modifiable: • Age: risk doubles each decade after age 55 • Sex: men have higher stroke rates, but women are more likely to die from stroke • Family history of stroke • Sickle cell disease Modifiable (can be changed or treated): • Hypertension: the single most important risk factor for stroke in Nigeria • Diabetes mellitus • High cholesterol • Heart disease (especially atrial fibrillation) • Smoking • Excessive alcohol consumption • Obesity and physical inactivity • Oral contraceptive use combined with smoking (particularly in women over 35) • Stress and lack of sleep

• Paralysis or weakness: affecting one side of the body (hemiplegia/hemiparesis) • Difficulty speaking or understanding language (aphasia) • Difficulty swallowing (dysphagia): increases risk of aspiration pneumonia • Memory loss, cognitive impairment, and vascular dementia • Emotional changes: depression, anxiety, emotional lability (uncontrolled laughing or crying) • Chronic pain • Pressure sores and deep vein thrombosis from immobility • Urinary and bowel incontinence • Recurrent stroke: the risk of a second stroke is highest in the days and months after the first • Death: stroke is one of the top three causes of death in Nigeria

Up to 80% of strokes are preventable by managing risk factors: Control blood pressure: • The most powerful stroke prevention measure: take antihypertensive medication exactly as prescribed • Monitor blood pressure regularly Healthy lifestyle: • Do not smoke: quit if you currently smoke • Eat a heart-healthy diet: reduce salt, saturated fats, and processed foods; increase fruits and vegetables • Exercise regularly: at least 150 minutes of moderate activity per week • Maintain a healthy weight • Limit alcohol to low amounts Manage other conditions: • Control diabetes and high cholesterol with medication and lifestyle change • Treat atrial fibrillation with anticoagulants (blood thinners) as prescribed • Manage sickle cell disease appropriately After a TIA or first stroke: • Take antiplatelet or anticoagulant medication as prescribed • Attend all rehabilitation and follow-up appointments