This questionnaire-based study, involving 6210 parents of individuals aged 0–18, is, to date, the largest study about children and adolescents’ experience during the COVID-19 pandemic and the effects on their physical and mental health.
Similar to other countries, Italy experienced a total lockdown from March 11 to May 18, 2020. As expected in a period of isolation, uncertainty and general concern, feelings of loneliness, sadness, or trouble were present in most of children and adolescents.
One of the most striking finding in our study is the increase in sleep disorders relating to problems with falling asleep, maintaining sleep, and the presence of nightmares and/or sleep terrors.
As our questionnaire asked for the “age of the youngest child” and the questions focused on all children in the household, we were not able to make an exact breakdown by age group. Consequently, this result is hardly comparable to the few existing data in the literature: all but one of them concern pre-school children (aged 3–6). Moreover, they all have smaller samples and use different parameters. Some of them report a negative impact on sleep quality with alterations in sleep routines: a French study on 92 children (median age 29 months) highlighted an increased total SDSC score during the lockdown, with major difficulties in initiating and maintaining sleep, and an increased frequency of parasomnias [24]. An Italian study on 37 children aged 3–6, carried out during lockdown through repeated parental reports, found that after an initial phase of worsened sleep, there was a stabilization of its routine and quality [11]. Others found no effect of the lockdown: a study on 1619 Chinese children aged 4–6 years showed no difference in the Children’s Sleep Habit Questionnaire (CSHQ) scores compared to old surveyed in 2018 [25]. A smaller Italian retrospective study found no significant effect of the lockdown on SDSC score [26]. A larger (n = 1472) Canadian survey focusing on school children and youth (5–17 years) showed no differences in terms of sleep quality but reported increased total sleep duration, more evident in adolescents than in children [12].
Sleep disorders are relatively frequent in paediatric populations and are linked to behavioural and emotional problems both in children and adolescents [27,28,29,30]. Isolation imposed during the lockdown may compromise children’s ability to successfully regulate behaviour and emotions and consequently there is potential for sleep problems to emerge or worsen [31]. Our results confirm this hypothesis: we found a higher frequency of sleep disturbances among those children and adolescents in our population who appear to experience feelings of loneliness, sadness, worry, or nervousness. Sleep disorders were also found to be linked to the presence of other factors “unmasking” the distress in children and adolescents such as changes in food intake.
Social and psychosocial factors also appear to influence sleep disturbance. We found that the perception of family economic instability and job insecurity, even without a change in the employment situation during the pandemic, is a risk factor for problems related to the initiation and maintenance of sleep. This result can be directly traced to the known influence that anxiety, depression (especially maternal) and parental stress have on toddlers’ sleep [26, 32], and, on the other hand, in older children and adolescents, to a direct understanding of family experience, spells of unemployment and parental concern [3]. Before this pandemic, several authors had reported financial loss as a risk factor for psychological disorders and both anger and anxiety during and after quarantine [33,34,35]. It has also been suggested that sleep disorders in children manifest a socio-economic gradient, the causes of which, however, have not been identified [36]. It was thus not surprising that, in the case of parental job loss, also nightmares and terrors occurred more frequently, revealing a much deeper state of concern in the child/adolescent. As some authors report, the inability to make meaning of traumatic or unusual elements may lead to misleading or biased cognitive appraisal and emotional overreactions [37], that may contribute to the pathogenesis of sleep disturbance.
About a possible selection bias, we interestingly found that some socio-economic elements significantly associated with higher child distress (i.e. difficult economic status and/or worsened after the outbreak, parental job loss) were more frequent among excluded individuals whose parents did not provide information about sleep disturbances, so the prevalence of these conditions in the general population may be higher than what we estimated. However, we cannot exclude that respondents to the questionnaire possess cognitive, behavioural, and cultural traits that increase their levels of attention and anxiety towards their offspring’s health conditions, leading to an overestimation of all prevalence figures in our study sample.
Unexpectedly, children of healthcare workers (2.4% of our sample) directly involved in pandemic management and usually experiencing chronic stress and higher levels of depression and anxiety [38], did not show a higher rate of sleep disorders.
In our population, difficulty in falling asleep, nocturnal awakenings, and nightmares and/or sleep terrors were higher in children who were reported to miss outdoor activity. Outdoor activity is related to a better quality of sleep [39]; a recent study also demonstrated that sufficient time spent outdoors is associated with a decreased risk of inadequate sleep time in children. The association seems to be age- and gender-dependent, being stronger in 6–13 year-old males [40]. We could therefore hypothesize that the sleep of a sub-group of children more prone to physical activity (and therefore missing it more) can be affected even more negatively by lockdown and consequent reduced outdoor activity.
Moreover, the inability to go outside, remote learning, and the absence of in-person social interactions lead to a higher amount of time spent using technology, even during the pre-sleep period [13]. The reduced exposure to the sunlight and the prolonged exposure to screen blue and bright light may contribute to determine the sleep disorder by disrupting the physiological circadian rhythm [39,40,41,42,43].
About additional possible risk factors, Becker and Gregory have suggested that youth with pre-existing psychopathologies and neurodevelopmental conditions may be particularly vulnerable to disturbed sleep during this pandemic [13]. In our survey we investigated 6 groups: learning disabilities, ASD, other disabilities, chronic conditions, and multiple conditions. No differences between these groups have been found except for a higher rate of difficulty in staying asleep in the “chronic disease” group and of difficulty in falling asleep in the “multiple conditions” group. Unfortunately, since these two groups include patients with very different characteristics, no further speculation is possible.
Regarding unusual repetitive movements we interestingly observed an increased incidence among children with ASD and other disabilities. We therefore suggest that in these cases the “ unusual repetitive movements” may be stereotypies (rather than tics as suggested in the questionnaire), which are frequent in patients with ASD and severe cognitive impairment [44] and might be increased as an expression of anxiety and distress in these patients [45,46,47,48]. However, further specific studies with targeted questions are necessary to confirm this supposition.
Finally, an interesting fact to note, although not univocally explainable with our data, is the higher rate of feelings of loneliness, sadness, or trouble in the group of children with specific learning disorders. Their parents also reported a greater discomfort compared to children without other pathologies or disabilities in paying attention during distance-learning classes. They also expressed feelings of inadequacy in supporting their children’s distance learning and helping them manage their anxiety related to it. Unfortunately, the number of children with learning disabilities is too low to reach a conclusion. Further targeted studies could be useful to clarify this point, as a higher stress rate in engaging distance learning has already already been reported in case of specific learning disorders [49].
Our study has several limitations. The first possible bias is that, as this survey was promoted predominantly by social media, we cannot know the real number of people who received the invitation to participate in the survey and, consequently, the response rate. Moreover, such a study design could limit the ability to reach groups that do not have access to the Internet and thus exclude a population that might be particularly at risk of suffering from the pandemic aftermath. Finally, the inherent limitation of parent response-based questionnaires may not always coincide with the child’s perception and be influenced by numerous factors including parental stress itself.