Close Counts in Horseshoes and Sleep Apnea

Continuous positive airway pressure therapy improves sleep apnea

(RxWiki News) Researchers wanted to observe if patients with slight obstructive sleep apnea (OSA), those close to but not quite qualifying by current standards for a prescription of continuous positive airway pressure (CPAP), would benefit from CPAP therapy.

CPAP is a ventilation device that blows a gentle stream of air into the nose during sleep to keep the airway open and is prescribed for moderate to severe OSA in patients to facilitate breathing while sleeping.

"Patients with slight OSA had their daytime sleepiness dramatically reduced by CPAP."

Sonya Craig, research fellow at Churchill Hospital, Oxford found the results surprising. CPAP therapy truly reduces daytime sleepiness and improves quality of life in patients with very limited symptoms.

While it has been well-known that CPAP helps patients with more dramatic daytime sleep issues, now it is known that the same therapy helps less severe cases of OSA as well.

Craig continued to note that the dramatic improvement in sleepiness and quality of life scores was much greater than anticipated, especially given  the patients had very limited symptoms. One take out of the study Craig suggests is that current clinical assessment of patients with OSA does not reliably predict all patients likely to benefit from CPAP.

Dr. Craig also suggests further evaluation will focus on determining if the benefits from CPAP in this subset of patients are only a short-term improvement or could they be long-lasting. The Epworth Sleepiness Score evaluated the change in daytime sleepiness measured at the start of the study, and again at follow-up six months later.

The Study

  • 341 patients from 10 medical centers, with proven OSA but insufficient current symptoms as judged by both the patient and the sleep physician to prescribe CPAP therapy
  • Two groups: Six months of CPAP or no treatment
  • Oxford Sleep Resistance Test (OSLER) wakefulness and sleepiness 
  • Quality of life was assessed by a standard questionnaire.
  • After six months of treatment, CPAP significantly reduced daytime sleepiness and increased wakefulness compared to the standard treatment group
  • Falling asleep during OSLER test, which requires patients to lie quietly and react to a flashing light for prolonged periods of time repeatedly was 49 percent less in CPAP treatment group
  • Quality of life scores were also significantly higher in the CPAP group
  • 25 percent of patients stopped CPAP treatment prior to the end of the study, reporting that they did not perceive enough benefit
Review Date: 
May 16, 2011