Risk factors of stroke Stroke is a neurological emergency. Stroke occurs as an end result of diminished blood supply to brain. It produces significant morbidity and mortality in the society. About 20% of patients die within 1 month of stroke attack. It has both modifiable and non modifiable risk factors. Treatment of modifiable risk factors will help in reducing about 80% stroke in the community.
General risk factors for stroke
Non-Modifiable risk factors
- Age - Age more than 55
- Gender - Male
- Race (ischemic stroke): blacks > whites > Asians
- History of stroke or TIA.
15-30% of strokes are preceded by TIA.
35% of pts with TIA will have stroke within 5 years.
10% risk of recurrent stroke within first years of stroke.
(TIA – transient ischemic attack).
- Family history.
- Fibromuscular Dysplasia.
- Patent Foramen Ovale (PFO or hole in the heart).
Modifiable risk factors
Modifiable risk facrors are divided into medical disorders and lifestyle disorders.
Medical Risk Factors
High Blood Pressure.
Atrial Fibrillation.
High Cholesterol.
Diabetes.
Atherosclerosis.
Circulation Problems.
Lifestyle risk factors
Smoking.
Alcohol use.
Physical Inactivity.
Obesity.
High risk factors for ischemic stroke
General population (0.6 %/yr)
Asymptomatic carotid bruit : 1.5 %/yr.
Prior myocardial infarction : 1.5 %/yr.
Asymptomatic carotid stenosis : 2.0 %/yr.
Nonvalvular atrial fibrillation : 5.0 %/yr.
History of TIA : 6.0 %/yr.
Prior ischemic stroke : 10 %/yr.
Rare risk factors
Thrombocythaemia and thrombophilia ( increased platelet count )
Polycythaemia ( Increased hemoglobin)
Anticardiolipin and lupus anticoagulant antibodies (i.e. antiphospholipid syndrome).
Endocarditis ( infection of heat valve)
Low-dose oestrogen-containing oral contraceptives
Migraine
Vasculitis (SLE, polyarteritis nodosa, giant cell arteritis, granulomatous CNS angitis)
Amyloidosis
Hyperhomocysteinaemia
CADASIL (cerebral dominant arteriopathy with subcortical infarcts and leucoencephalopathy)
Reduction of stroke risk following control of risk factors