A study published in the June 1st issue of the journal SLEEP finds that longer nightly duration of continuous positive airway pressure (CPAP) use can help those suffering from obstructive sleep apnea (OSA) achieve normal daytime functioning.
The study, conducted by Terri E. Weaver, PhD, of the University of Pennsylvania, focused on 149 patients with severe OSA at seven sleep centers in the United States and Canada. Before treatment and again after three months of CPAP, the participants completed a day of testing that included measures of daytime sleepiness and functional status.
The findings indicated that a greater percentage of participants impaired prior to the initiation of CPAP achieved decreased daytime sleepiness and enhanced functioning to normal levels with longer nightly CPAP durations.
Dr. Weaver identified a couple of important clinical measures from this study.
"From a population sense, functions for predicted probabilities of normalization show that more CPAP use is associated with greater relief of sleepiness, no matter how it's measured," said Weaver.
According to Dr. Weaver, there are also patients who normalize on therapy with somewhat limited CPAP use.
"The actual need for CPAP in terms of reversing sleepiness is likely to be individually determined," said Weaver. "We cannot assume that an individual using CPAP only four hours per night is inadequately treated for sleepiness outcomes. We also cannot assume that the patient is effectively treated. Therefore, it is important to evaluate treatment effectiveness by assessing the level of adherence in conjunction with treatment outcomes."
Dr. Weaver noted that there are, in contrast, individuals who remain excessively sleepy despite more than seven hours of CPAP use per night. The determination of a recommended nightly duration of CPAP use is also dependent on which outcome is viewed as the most reflective of clinical improvement, added Weaver.