If a patient has a sudden awakening while sleeping, the reasons are as follows: 1. Consider mental tension due to external factors, sympathetic nerve overexcitation caused by poor sleep, commonly seen in patients with plant nerve dysfunction or cardiac neurosis, prone to sudden awakening during sleep. 2. Patients with a previous history of diabetes, if symptoms of hypoglycemia occur during sleep, some patients will also have sudden awakening 3. cardiovascular diseases, such as coronary artery disease, unstable angina pectoris, arrhythmia or myocarditis, may cause sudden awakening during sleep due to sudden narrowing and spasm of the coronary arteries. 4. cerebrovascular diseases, such as acute stroke, may also cause sudden awakening during sleep.