Nocturnal Cough

Excerpt

A cough is a symptom and a reflex action that is an essential protective and defensive act that secures the removal of mucus, noxious substances, and infections from the larynx, trachea, and larger bronchi. Impairment or absence of the coughing mechanism can be dangerous and even fatal in disease. Women tend to have a chronic cough more often and have heightened cough reflex sensitivity compared to men. Nocturnal cough is distressing and may cause disturbances in sleep.

The cough reflex has three components:

1. Afferent sensory limb

2. Central processing center

3. Efferent limb

This cough reflex has neuroplasticity in such a way that hypersensitive response is triggered over time because of the cough itself causing chronic irritation and inflammation and leading to tissue remodeling.

Asthma is a highly prevalent chronic respiratory disease with nocturnal cough as one of the presenting features. In asthma, symptoms usually worsen at night and cause awakenings affecting the quality of life. Marsden et al reported that the parameter of nocturnal cough could be a valid indicator for asthma control. However, still, more information is needed regarding cause-effect relationships and longitudinal trends of nocturnal cough in asthma.