There are many reasons for a strong cough in the middle of the night, including cough variant asthma, colds, heart disease, respiratory infections, etc., as follows: 1. Cough variant asthma: The airways of asthma patients are highly reactive, and as the excitability of the vagus nerve of the body increases in the evening, the sensitivity of the patient’s airways also increases, which can make the patient’s cough symptoms more severe in the middle of the night. 2. Colds: Some patients with coughs after colds can also have coughs that worsen at night. 3. Patients with a cough after a cold can also have a cough that worsens at night.3. Heart disease: Patients with chronic heart failure, for example, have a cough that worsens in the evening due to increased pulmonary stasis when they sleep in a flat position.4. Patients with respiratory infections: Patients with mycoplasma pneumonia, in particular, can have a frequent cough at night that affects sleep quality.