Why does coughing increase during the night hours?
The shift in position changes the flow of mucous in your trachea, thus causing discomfort, which makes your diaphragm spasm. As the trachea is lined with tiny hair-like membranes called Cilia, and they move mucous up the wind pipe to the Oronasalpharynx (where your nose and mouth meet). Since you spend most of your time upright, the body needs to adjust to the change in position. Also, you have to take into account environmental changes. At night the air becomes more humid, thickening mucous. The colder air agitates the wind pipe making coughing more likely, and you move into the home at night, where more dust and particle build up occurs due to the high volume of human traffic and lesser ventilation compared to most professional/public areas. (and traffic is in respect to surface area and time occupied, not per person count).
