Such symptoms of asthma as wheezing, cough and shortness of breath are known as nocturnal asthma if they take place in the middle of the night. For many people, asthma attacks are most severe at night. In such a situation, symptoms usually occur between midnight and 8 a.m., particularly around 4 a.m. Nocturnal asthma is not always obvious to healthcare providers, and it is not often reported by patients. Symptoms may be misdiagnosed, and recognized as symptoms of other medical conditions that can be active at night, such as congestive heart failure, gastroesophageal reflux, a breathing problem known as obstructive sleep apnea or another respiratory problem.
This kind of asthma is widespread. The research of 8,000 asthmatic patients revealed that nearly fifty per cent had nighttime symptoms during most nights, and two thirds of the subjects experienced nighttime symptoms at least three times weekly. Frequent nocturnal symptoms are a sign of poorly controlled asthma and ought to be discussed with your physician.
Normally, nocturnal asthma is caused by a combination of a few factors:
* Allergens occur in house dust and bedding (both contain debris from dust mites). When you shift position on top of your pillow and mattress, you can stir up a small "cloud" of dust mite allergens that circulate close to your nose and mouth until they settle. Not much dust mite allergen is necessary to activate symptoms in a person who is allergic, especially when they are concentrated right around your nose.
* Pet dander (if you keep pets indoors) and pollens (that can enter open windows, or can recirculate into the air from clothing that was worn outside, if it hasn’t been put into a basket) are other a common "bedroom" triggers for nocturnal asthma.
* It sometimes happens that nocturnal asthma occurs as a consequence of daytime exposure to allergens that lead to a delayed attack hours later.
* Airway secretions may also contribute to nocturnal asthma; nearly seventy per cent of asthma sufferers have chronic sinusitis and/or postnasal drip. Clearing the sinuses could improve both daytime and nighttime symptoms.
* Sleep apnea, a disorder in which breathing temporarily stops in the course of sleep, may also happen to people suffering from asthma. Even though sleep apnea is an upper-airway condition, it can activate reflexes that bring about an attack in the lower airways.
* Circadian rhythms — your body clock — may also play some important role. Circulating blood levels of epinephrine and steroids, both of which protect against asthma, are lowest between 4 and 8 a.m., which leaves patients particularly susceptible at that time.
If you experience symptoms that may result from nocturnal asthma, you should immediately contact your healthcare provider for an examination and advice.
