Arousal threshold modifies the effect of CPAP on executive function among individuals with obstructive sleep apnea.

Unlabelled: Arousal Threshold Modifies the Effect of CPAP on Executive Function Among Individuals with Obstructive Sleep Apnea.

Background: Obstructive Sleep Apnea (OSA) is associated with neurocognitive dysfunction. However, randomized trials evaluating the effects of continuous positive airway pressure (CPAP) on neurocognition in those without dementia do not show a benefit. We thus aimed to assess whether arousal threshold (ArTH) modifies the effect of CPAP on neurocognitive function.

Methods: We performed a secondary analysis of a randomized, sham-controlled trial, Apnea Positive Pressure Long-term Efficacy Study. ArTH was estimated from polysomnography using a translatable method (Sands ., SLEEP 2018). Neurocognitive outcomes included the Sustained Working Memory Test-Overall-Mid-Day score (SWMT-OMD, executive function, primary outcome), with the Pathfinder Number Test - total time (attention) and Buschke Selective Reminding Test - sum recall (learning and memory) as secondary outcomes. Generalized linear modeling assessed whether the effect of CPAP was modified by baseline ArTH (treatment-by-ArTH interaction). 833 participants with OSA, [apnea-hypopnea index (AHI) ≥10 events/h], available ArTH, and outcomes were analyzed (CPAP n=437, Sham n=396).

Results: For executive function, the effect of CPAP treatment was modified by ArTH (p-interaction=0.042). Specifically, for every 1 sd increase in ArTH, the SWMT-OMD score improved by 0.10 95% CI (0.01, 0.18) in active compared to sham CPAP at 6 months; At ArTH 1 sd above the mean SWMT-OMD improvements were nearly three times that in those with average ArTH (0.139 [0.018, 0.261] 0.053 [-0.034, 0.140] respectively. No effect modification was observed for attention (p=0.311) or learning and memory (p=0.744).

Conclusion: In OSA, a higher ArTH is associated with greater improvements in executive function following CPAP therapy.