Nocturnal Asthma (Nighttime Asthma)
Nocturnal asthma, with symptoms like chest tightness, shortness of breath, cough, and wheezing at night, can make sleep impossible and leave you feeling tired and irritable during the day. These problems may affect your quality of life overall and make it more difficult to control your daytime asthma symptoms.
Nocturnal or nighttime asthma is very serious. It needs a proper asthma diagnosis and effective asthma treatment.
Nighttime Asthma and Sleep Disturbance
The chances of experiencing 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 Causes
The exact reason that asthma is worse during sleep are not known, but there are explanations that include increased exposure to allergens; cooling of the airways; being in a reclining position; and hormone secretions that follow a circadian pattern. Sleep itself may even cause changes in bronchial function.
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.
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.
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.
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.
If you are frequently bothered with heartburn, the reflux of stomach acid up through the esophagus to the larynx may stimulate a bronchial spasm. It's worse when lying down or if you take medications for asthma that relax the valve between the stomach and esophagus. Sometimes, acid from the stomach will irritate the lower esophagus and lead to constriction of your airways. If stomach acid backs up to your throat, it may drip down to the trachea, airways and lungs, leading to a severe reaction. This can involve airway irritation, increased mucus production, and airway tightening. Taking care of GERD and asthma with appropriate medications can often stop nighttime asthma.