Revisiting The Apnea Positive Pressure Long-term Efficacy Study (APPLES)
The significance of The Apnea Positive Pressure Long-term Efficacy Study explained
What is the APPLES study?
The Apnea Positive Pressure Long-Term Efficacy Study (APPLES) is a randomized, double-blinded, sham controlled, multi-center study that was designed to assess the long-term effectiveness of nasal CPAP therapy for obstructive sleep apnea (OSA).
What did this study want to achieve?
- To assess the long-term effectiveness of CPAP therapy on neurocognitive function, mood, sleepiness, and quality of life by administering a comprehensive, yet novel neurocognitive test battery to a large group of OSA subjects assigned to either Active or Sub-therapeutic CPAP therapy in a double-blinded randomized manner.
- To identify specific deficits (impairments, defects) in neurocognitive function associated with OSA in a large, heterogeneous population of OSA subjects.
- To determine which deficits in neurocognitive function in OSA subjects are reversible and most sensitive to the effects of CPAP.
- To use statistical methods to assess the clinical effectiveness of CPAP in improving neurocognitive abilities, quality of life, mood, and sleepiness in OSA patients.
- To use Functional Magnetic Resonance Imaging (fMRI) on a subset of OSA subjects to determine differences in the pattern of cortical (brain) activation before and after CPAP therapy and to assess whether this (any) change is associated with improvement in the performance of specific neurocognitive tasks.
The study's benefits to sleep technology
The study was important in that it showed whether CPAP usage effectively treats the debilitating consequences of OSA in the areas of neurocognitive function, mood, sleepiness, and quality of life for OSA patients.
How did the study go?
According to a report on the APPLES study, CPAP treatment improved both subjectively and objectively measured sleepiness, especially in individuals with severe OSA (AHI > 30). CPAP use resulted in mild, transient improvement in the most sensitive measures of executive and frontal-lobe function for those with severe disease, which suggests the existence of a complex OSA-neurocognitive relationship.
What the study means for sleep technologists
The findings from this study emphasized the need to differentiate “obstructive sleep apnea” from “obstructive sleep apnea syndrome.”
In the AAST Journal Club article on the APPLES study, Dr. Rich Rosenberg and Dr. Clete Kushida, Medical Director at the Stanford Sleep Medicine Center discuss the results of the APPLES study, a long term study of the effects of CPAP on neurocognitive function and analyzes the concerns about the design of the study and reviews the results.
To gain access to the Journal Club Article click here, and remember! The module is available at a discounted price for AAST members!