Sleeping under the waves: a longitudinal study across the contagion peaks of COVID-19 pandemic in Italy

After the March–April 2020 COVID-19 outbreak, a second contagion wave afflicted Europe in autumn. This study aimed to evaluate sleep health/patterns of Italians during this further challenging situation. A total of 2013 Italians longitudinally participated in a web-based survey during the two contagion peaks of the COVID-19 outbreak. We investigated the risk factors for sleep disturbances during the second wave, and we compared sleep quality and psychological well-being between the two assessments (March–April and November–December 2020). Female gender, low education, evening chronotype, being at high-risk for COVID-19 infection, reporting negative social or economic impact, and evening smartphone overuse predicted a higher risk of poor sleep and insomnia symptoms during the second wave. Advanced age, living with high-risk subjects for COVID-19 infection, and having a relative/friend infected with COVID-19 before the prior two weeks were risk categories for poor sleep quality. Living with children, having contracted COVID-19 before the prior two weeks, being pessimistic on the vaccine, and working in healthcare were risk factors for insomnia symptoms. The follow-up assessment highlighted reduced insomnia symptoms and anxiety. Nevertheless, we showed reduced sleep duration, higher daytime dysfunction and sleep medication use, and advanced sleep phase, confirming the alarming prevalence of poor sleepers (∼60%) and severe depression (∼20%) in a context of increased perceived stress. This study demonstrated a persistent impact of the COVID-19 pandemic on sleep and mental health. Large-scale interventions to counteract the chronicity and exacerbation of sleep and psychological disturbances are necessary, especially for the risk categories.