Thursday, April 24, 2014
what can you tell me about nocturnal asthma and can it be misdiagnosed as obstructive sleep apnea?
Both asthma and obstructive sleep apnea can result in disrupted sleep. Some patients have worsening of asthma at night because of exposure to bedroom allergens (for example, dust mites or pets that sleep in the bedroom) and other patients have worsened asthma because their controller medications wear off before the person wakes up in the morning.
There are some ways to distinguish nocturnal asthma from sleep apnea. Asthma tends to cause persons to wake up with cough or shortness of breath that typically improves with inhaler use. Sleep apnea tends to cause persons to wake up needing to urinate or with shortness of breath that improves quickly upon awakening. Sleep apnea can also cause vivid dreams, sweating, and loud snoring. Patients with sleep apnea are also more likely to be excessively sleepy during the daytime.
Asthma and sleep apnea are both common conditions and some patients can have both. One way of helping to distinguish between the two is use of a home peak flow monitor that the person can use when they wake up to determine if their peak flow rate is normal for them (meaning that sleep apnea is more likely) or if the peak flow rates are reduced (meaning that asthma is more likely).
James N Allen, Jr, MD
Clinical Professor of Pulmonary, Allergy, Critical Care & Sleep Medicine
College of Medicine
The Ohio State University