OSA Delaying Diagnosis of Narcolepsy

Abstract

Narcolepsy is a disorder characterized by excessive daytime sleepiness, sleep paralysis, cataplexy, hypnopompic or hypnagogic hallucinations. The possibility of narcolepsy in a patient may be overlooked owing to its low prevalence, symptomatology and coexistent disorders. Nevertheless, it can cause significant impairment in functioning of an individual. Obstructive sleep apnea is one of the disorders which can be comorbid with narcolepsy and result in delay in diagnosis. OSA also presents with excessive daytime symptoms and is easily considered as a differential diagnosis due to its higher prevalence. Residual symptoms even after correction of OSA can be due to various reasons. The possibility of a missed narcolepsy should be deliberated even in the absence of the classic tetrad. In this case report, we describe a young male who presented with excessive daytime sleepiness and was diagnosed of OSA initially. Persistence of symptoms warranted a re-evaluation and patient was eventually diagnosed as a case of narcolepsy, established by appropriate studies in the sleep laboratory.