Persistent Sleepiness After Effective Positive Airway Pressure Therapy Deserves Independent Clinical Evaluation

Positive airway pressure (PAP) therapy often improves excessive daytime sleepiness in obstructive sleep apnea (OSA), yet effective control of sleep-disordered breathing does not invariably restore normal daytime alertness. Persistent sleepiness after PAP therapy should therefore be regarded as a clinical observation requiring explanation rather than automatically attributed to treated OSA. The term "residual excessive daytime sleepiness" may become misleading when it is interpreted as an etiologic conclusion rather than a descriptive label. Evaluation should distinguish PAP adherence from treatment efficacy and symptomatic recovery, determine whether the complaint reflects sleepiness rather than fatigue or apathy, and consider alternative contributors including insufficient sleep, circadian misalignment, medication or substance effects, medical and psychiatric conditions, coexisting sleep disorders, and central disorders of hypersomnolence. Additional testing should be guided by a defined clinical question, and wake-promoting therapy should follow rather than replace diagnostic reassessment. Persistent sleepiness after effective PAP describes an observation, not an etiology, and deserves independent clinical evaluation.