Since when can obstructive sleep apnea be ruled out just because someone doesn’t have daytime symptoms such as excessive sleepiness, headaches, irritability, difficulty concentrating and easily falling asleep while watching TV and reading?
When a sleep study (polysomnography) indicates anywhere from five to 15 disrupted breathing events per hour, the diagnosis is mild sleep apnea.
Even in the absence of daytime symptoms.
It’s easy to assume that someone actually DOES have symptoms but is not aware.
For example, a person may not realize that falling asleep during a boring TV show is triggered by sleep apnea rather than a boring TV show.
People who fall asleep as car passengers may attribute this to a smooth quiet ride.
Those who doze off while at work before a computer may blame it on the tedious nature of the work. Falling asleep during a meeting or lecture may be blamed on boredom.
Lack of energy or frequently feeling drained may be blamed on stress, anxiety, lack of exercise and/or “getting older.”
On the other hand, there truly are people with obstructive sleep apnea who have no daytime symptoms.
• Never feel a need to nap
• Never get drowsy driving, watching TV or reading
• Never experience jet lag
• Are very physically active
• Can get by on six hours of sleep
• Never feel fatigued, exhausted or drained
Nevertheless, many physicians recommend CPAP therapy for those diagnosed with mild obstructive sleep apnea even in the absence of daytime symptoms.
Other sleep medicine doctors question the value of CPAP for those with asymptomatic mild obstructive sleep apnea.
“Apart from the difficulty in documenting improvement with CPAP in mild OSA, the issue of acceptance and adherence should be taken into account,” states a paper in Journal of Clinical Medicine (April 2007).
“For example, a randomized study of the diagnosis of OSA by either polysomnography or home portable monitor followed by autotitrating PAP treatment was performed,” continues the paper.
“Of 32 patients undergoing polysomnography with an AHI less than 10, 10 had improved quality of life at 4 weeks and 4 continued to adhere with APAP for 3 or more months.”
AHI is the apnea hypopnea index. Its associated numerical value refers to the average number of these events per hour of sleep.
Hypopnea refers to inhaling against resistance created by a partially rather than completely obstructed airway.
“In summary, patients with mild OSA are not usually improved by PAP treatment,” continues the report, “and even if improved are not likely to be adherent.”
It is not known whether the cardiovascular risk of untreated mild OSA—for which there are no daytime symptoms—is lower than for untreated mild OSA with daytime symptoms.
Some people with mild OSA without daytime symptoms will eagerly comply with CPAP therapy—once they learn about the life threatening complications of untreated OSA in general.
Others with asymptomatic mild OSA will abandon the idea of CPAP therapy once they learn that studies about cardiovascular risk in untreated mild OSA are not conclusive.
“Cohort studies of mortality with CPAP treatment suggest that only those patients with an AHI greater than 30 have a reduced mortality,” states the paper. The same holds true for an apnea index exceeding 20.
“For example, in a retrospective analysis of OSA only those patients with an AI greater than 20 had substantial mortality over 9 years,” continues the JCM.
The JCM also points out that for mild OSA with daytime symptoms, non-CPAP alternatives may be effective. These include weight loss, changing sleep position, mandibular appliance and nasal corticosteroids for those with allergic rhinitis.