Yawning again and again tends to attack stroke in heart and brain

When people feel tired, they often perform several yawn, which can temporarily reduce human's fatigue. However, if the elderly, especially patients with hypertension and arteriosclerosis, frequently yawn, it may be the precursor of ischemic stroke, so patients should be vigilant.
About 70% to 80% of patients with ischemic stroke, about one week before the onset, because of brain ischemia and hypoxia they have the phenomenon of frequent yawning. The reason is that the elderly, particularly patients with hypertension or cerebral arteriosclerosis, due to atherosclerosis, luminal narrowing, vessel wall elasticity reducing, resulting in reduced blood flow to the brain, the brain is very sensitive to oxygen. The brain, only accounts for about 2% of total body weight, but it consumes about 25% of whole oxygen demand of the body, therefore, when the brain occurs ischemia and hypoxia, it frequently leads to yawn.
Meanwhile, the yawn can make intrathoracic pressure decrease, the blood from superior and inferior vena cava returning to the heart increase, and cardiac output of blood increase, so the blood supply ability of the brain cells gets improved. However, this improvement is temporary, therefore frequent yawning often indicates that ischemic stroke may occur in the near future.