Asthma Health Center
Nocturnal Asthma (Nighttime Asthma)
Does nocturnal asthma disturb your sleep? Nocturnal asthma, with its chest tightness, shortness of breath, cough, and wheezing at night, can make sleep impossible. Nocturnal asthma , regardless of the time of day, can ruin sleep, leaving you feeling tired and dull during the day. But nocturnal or nighttime asthma is also very serious and needs a proper asthma diagnosis and effective asthma treatment.
Nighttime Asthma and Sleep Disturbance
The chances of asthma symptoms are higher during sleep. Nocturnal wheezing, cough, and trouble breathing are common yet potentially dangerous. Many doctors often underestimate nocturnal asthma or nighttime asthma.
Studies show that 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.
Nocturnal Asthma Causes
The exact reasons for why asthma is worse during sleep are not known. Still, there are many explanations for what may cause nocturnal asthma. Some of these may involve increased exposure to allergens at night, cooling of the airways, the reclining position, or hormone secretions that follow a circadian pattern. Sleep itself may even cause changes in bronchial function. Causes may include:
Increased Mucus or Sinusitis
During sleep, the airways tend to narrow, which may cause increased airflow resistance. This may trigger nighttime coughing, which can cause more tightening of the airways. Increased drainage from your sinuses can also trigger asthma in highly sensitive airways. Sinusitis with asthma is quite common.
Internal Triggers
Asthma problems may occur during sleep despite when the sleep period is taking place. People with asthma who work on the night shift may have breathing attacks during the day when they are sleeping. Most research suggests that breathing tests are worse about four to six hours after you fall asleep. This suggests there may be some internal trigger for sleep-related asthma.
Reclining Position
Lying in a reclining position may also predispose you to nighttime asthma problems. Many factors may cause this, such as accumulation of secretions in the airways (drainage from sinuses or postnasal drip), increased blood volume in the lungs, decreased lung volumes, and increased airway resistance.
Air Conditioning
Breathing colder air at night or sleeping in an air‑conditioned bedroom may also cause loss of heat from the airways. Airway cooling and moisture loss are important triggers of exercise‑induced asthma. They are also implicated in nighttime asthma, too.
GERD
If you are frequently bothered with heartburn, the reflux of stomach acid up through the esophagus to the larynx may stimulate a reflex associated with a bronchial spasm. This reflux is worse when you lie down and if you take certain medicines for asthma, which relax the valve between the stomach and the esophagus. Sometimes, acid from the stomach will irritate the lower esophagus and may activate the vagus nerve, which sends signals to the bronchial tubes that result in bronchoconstriction. If acidic gastric juice regurgitates all the way up the esophagus to the back of the throat and some of it drips down into the trachea, bronchi, and lungs, a severe reaction may take place. This can involve airway irritation, increased mucus production, and bronchoconstriction. Taking care of GERD and asthma with appropriate medications can often stop nighttime asthma.
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