AbstractIntroductionWhile COVID-19 is predominantly considered to be an acute self-remitting disease, it has been pointed out that a variety of symptoms can linger for several months, a phenomenon identified as long-COVID. Insomnia is particularly prevalent in long-COVID. In the present study, we aimed at confirming and characterising insomnia in long-COVID patients through polysomnography and to identify whether its parameters differ from patients with chronic insomnia and no long-COVID history.Materials and methodsWe conducted a case-control study, including 17 long-COVID patients with insomnia symptoms (cases), and 34 2:1 matched controls with a diagnostic of chronic insomnia and no history of long-COVID. All underwent a one-night polysomnography (PSG).ResultsFirst, we observed that long-COVID patients with insomnia complaints have altered PSG parameters, in favour of the diagnosis of chronic insomnia. Second, we show that insomnia related to long-COVID PSG parameters was not significantly different from regular chronic insomnia PSG parameters.DiscussionOur results indicate that even though it is one of the most prevalent symptoms of long-COVID, its related insomnia resembles typical chronic insomnia, based on PSG studies. Even though additional studies are warranted, our results suggest that the pathophysiology and therapeutic options should be similar to those recommended for chronic insomnia.