Nocturnal asthma is the occurrence of asthma symptoms at night or in the early morning hours. This can be distressing as symptoms may be severe. Nocturnal asthma can occur every night, a few times a week, or only once a week. Nocturnal or nighttime asthma is also very serious and needs a proper asthma diagnosis and effective asthma treatment. Most deaths related to asthma symptoms such as wheezing occur at night. Nocturnal asthma attacks can cause significant problems sleeping, resulting in sleep deprivation and daytime sleepiness, fatigue, and irritability. These problems may affect your quality of life overall and may make it more difficult to control your daytime asthma symptoms.
Causes for nocturnal asthma:
- Allergic factors: Exposure to certain allergens during the day can cause an asthma episode during sleep.
- Inflammation: For some patients with asthma, swelling of the airways increases at night.
- Airways cooling: Body temperature can drop during sleep and exposure to cold has been shown to trigger an asthma attack.
- Airway secretions: Chronic sinusitis and/or postnasal drip can cause symptoms of nocturnal asthma.
- Sleep apnea: Sleep apnea occurs in the upper airways, which may bring about an asthmatic response in the lower airways.
- Circulatory factors: Certain hormones and other chemicals that circulate in the body have been found to follow a circadian cycle that corresponds to changes in lung function at night.
- Gastroesophageal reflux (heartburn): Lying down may cause a reflux of gastric acid which irritates the esophagus.