The acute stages of the novel coronavirus (COVID-19) pandemic led to drastic and stressful changes in daily life, such as quarantine, social isolation, unemployment, and disrupted work-life routines. All these factors, along with distress and fear of getting infected, were associated with sleep problems with a high prevalence ranging from 17.4 to 57.2% in the general population (Cellini et al., 2020; Huang and Zhao, 2020). Moreover, COVID-19 pandemic-related sleep problems appeared to be persisting over time despite greater disease control and an increased intake rate of vaccinations (Li et al., 2021). Chronic poor sleep was associated with adverse long-term health outcomes (Khan and Aouad, 2017; Pigeon et al., 2017), especially among COVID-19 patients (Papagiouvanni et al., 2022). A recent systematic review on sleep and vaccination of influenza and hepatitis indicated a positive correlation between sleep and immune response (Rayatdoost et al., 2022). Sufficient and quality sleep was reported to double the antigen-specific immune response (Garbarino and Scoditti, 2021; Kow and Hasan, 2021).

During the COVID-19 pandemic, the sleep quality of caregivers with older children and adolescents was compromised (Peltz et al., 2020; Cellini et al., 2021; El-Osta et al., 2021; Ruppanner et al., 2021; Wearick-Silva et al., 2022), including later bedtime, poor sleep latency, and poor sleep efficiency (SE). However, reports among caregivers of young children (< 6 y) were mixed and few in number. Cumulative sleep loss among parents with young children is common (Falkingham et al., 2022) such that prior to the pandemic they experienced reduced nightly sleep duration in comparison to parents with older children (Hagen et al., 2013). Children's sleep may partly explain the deterioration of parental sleep (Sinai and Tikotzky, 2012; Rönnlund et al., 2016; Staples et al., 2019). Until the age of three, parents frequently report their child waking up at least once a week, which may disturb their sleep patterns (Scher et al., 2004). Poorer parental sleep is also linked to parenting stress during the first year postpartum (Sinai and Tikotzky, 2012). However, whether the pandemic further exacerbated these pre-pandemic associations is unclear. One cross-sectional study found 60% of caregivers of young children (< 6 y) reported worse sleep quality during the pandemic, and a higher clinical prevalence of insomnia symptoms compared to the pre-pandemic period (23 vs. 11%) (Zreik et al., 2020). These greater maternal insomnia symptoms were positively associated with their child's sleep latency, number of night awakenings, and wake time after sleep onset (Zreik et al., 2020). Further, another longitudinal study reported longer sleep latency and similar nocturnal sleep time among parents of young children as compared with the pre-pandemic period (Shinomiya et al., 2021). Yet, another longitudinal study indicated that there was no apparent change in parents of young children's sleep quality when compared with the pre-pandemic period (Kahn et al., 2021).

Multiple factors may have contributed to these mixed findings on caregiver sleep health, such as differences in pandemic-related impacts on daily life, mental wellbeing, socioeconomic status, and sleep-related behaviors (Bartoszek et al., 2020; Cellini et al., 2020; Zreik et al., 2020; Sosso et al., 2021; Peltz et al., 2023). Around 70% of caregivers reported that the COVID-19 pandemic consequently disrupted daily life, increased stress levels (American Psychological Association, 2020), and affected health behaviors (Janssen et al., 2020). Caregivers of young children faced the additional responsibilities of dealing with fluctuating stay-at-home orders and childcare, balancing work and family at home, and making decisions regarding the health and vaccination of their children (Adams, 2020; Calvano et al., 2021; Prime et al., 2022). Further, the mental wellbeing of parents and caregivers deteriorated during the pandemic (Goldberg et al., 2021) including heightened depressive symptoms (Lyttelton et al., 2020; Collins et al., 2021; Johnson et al., 2021). They worried about family health and broader global issues such as the national economy and impacts on their family's financial stability. Additionally, around 40–54.2% of parents reported reduced family income due to the COVID-19 crisis (Karpman et al., 2020; Zreik et al., 2020). However, few studies examined the predictors of poor sleep among parents and caregivers with young children during the COVID-19 pandemic.

This study aims to describe changes in sleep patterns among parents and caregivers with young children prior to and during the early stages of the COVID-19 pandemic and identify factors associated with insomnia symptoms and sleep efficiency. Based on the social-ecological model of sleep health (Grandner, 2019), we hypothesized that poorer mental wellbeing (individual level), poorer sleep-related behaviors (individual level), lower socioeconomic status (social level), and greater pandemic-related impacts on daily life (societal level), would independently contribute to poorer sleep quality.

To the best of our knowledge, the present study is one of few to investigate changes in sleep patterns and insomnia symptoms during the early wave of the COVID-19 pandemic among parents and caregivers of young children. Our findings indicated that more than half of parents and caregivers of young children experienced clinical levels of insomnia symptoms (51.5%) and poor sleep efficiency (65.8%), in line with other parental studies (Zreik et al., 2020; Wearick-Silva et al., 2022). Consistent with our original hypothesis, greater severity of insomnia symptoms was associated with lower income, greater depressive symptoms, more frequent arousal-associated activities and maladaptive sleep scheduling behaviors, less frequent sleep environment interferences, alterations in sleep-wake routine due to the pandemic, and greater impact of the COVID-19 pandemic on daily life. Lower sleep efficiency was associated with lower income and poorer sleep efficiency before the pandemic.

Low income was found to be strongly associated with insufficient sleep (Grandner et al., 2015), increased sleep latency (Lauderdale et al., 2006), and poorer sleep efficiency (Lauderdale et al., 2006; Friedman et al., 2007) before the pandemic. U.S. Bureau of Economic Analysis reported that at the start of the COVID-19 pandemic, personal income decreased by 413.8 billion USD (Garrison et al., 2022). Further, more than 40% of parents lost work-related income due to the COVID-19 outbreak (Karpman et al., 2020). Nearly 24 million were parents with young children (< 6 y) (Karpman et al., 2020). The reduced income during the pandemic was associated with greater depressive symptoms (Hibel et al., 2021), which may serve as a mediator between decreased income and both greater insomnia and lower sleep efficiency (Friedman et al., 2007; El-Sheikh et al., 2015). Additionally, the pandemic impacted individuals' health (Sherman et al., 2020). Health may also mediate the relationship between lower income and both shorter sleep duration and lower sleep efficiency (Friedman et al., 2007; Stamatakis et al., 2007).

In line with other studies during the pandemic (Salari et al., 2020), caregivers' depression prevalence was high (59.2%). A study monitoring 85,328 childcare centers in the U.S during the pandemic, indicated that April and May 2020 experienced the highest rate of childcare center closures between 59 and 70% (Lee and Parolin, 2021). A greater caregiving burden due to daycare closures (Russell et al., 2020), potentially compromised time for caregivers' self-care and emotional health. Additionally, fewer daycare attendance days may increase parental stress (American Psychological Association, 2020) and amplify parents' negative childcare feelings, such as being “irritated” and “tempted to hit my child” (Shinomiya et al., 2021). Finally, isolated individuals with limited social support had a higher risk for depression (Grey et al., 2020). These factors may contribute to greater depressive symptoms among parents (Lyttelton et al., 2020; Collins et al., 2021; Johnson et al., 2021). Similar to pre-pandemic (Morawetz, 2003), greater depression was also associated with greater insomnia symptoms during the pandemic (Bartoszek et al., 2020; Ye et al., 2020; Pizzonia et al., 2021).

Similar to other studies (Bacaro et al., 2020), poor sleep hygiene behaviors were associated with greater insomnia symptom severity. Work-life interruptions were related to poor arousal-associated behaviors (Gorgoni et al., 2021). During the pandemic, parents experienced decreased working hours compared with the pre-pandemic (Kochhar, 2020; Collins et al., 2021), and parents of children (< 5 years) were reported as having the least working hours (Kochhar, 2020). The reduced working hours may alter their sleep/wake routine and increase non-sleep promoting activities in the bedroom. Further, the pandemic-related disruptions created new conflicts due to partners' insufficient caregiving support (Calarco et al., 2020). The additional family conflicts may have led to greater cognitive arousal and unpleasant conversations prior to and during the sleep period. All these poor arousal-associated behaviors may contribute to greater insomnia severity.

In this study, nearly 90% of participants reported their sleep-wake routine was changed. They went to bed later during the pandemic than pre-pandemic (24:20 vs. 22:58) and the sleep midpoint was also delayed, similar to other studies (Bacaro et al., 2021; Di Giorgio et al., 2021). Altered sleep schedules may be partly driven by their children's sleep timing. For children who attended a nursery school for two or fewer days a week during the pandemic, both caregivers and the children had later wake-up times when compared to those of children attending a nursery school longer (Shinomiya et al., 2021). Consistent sleep schedules are essential to align caregivers' sleep-wake schedules to their endogenous circadian rhythm, allowing them to pursue better sleep quality (Gellis et al., 2014). Poor sleep scheduling behaviors and altered sleep-wake routines during the pandemic contribute to caregivers' greater insomnia severity.

Inconsistent with other studies (Desaulniers et al., 2018; Holbert et al., 2021), our findings indicated that greater sleep environment interferences were associated with less insomnia severity. Why the present study found an opposing association is unclear. Considering the moderate positive association between sleep environment and insomnia severity, and the strong positive associations between other SHPS scales and insomnia severity (Supplementary Table 2), suppression analysis was further conducted (Pandey and Elliott, 2010). We found that the involved suppressor variables included CES-D-10, arousal-associated behaviors, sleep scheduling behaviors, whether quarantine sleep-wake routine was changed and consistent with their personal preference, and CIS total (Supplementary Table 3). This suppression effect may be due to an underspecified model (Garbin, 2011).

COVID-related disruptions in daily life were positively related to worse insomnia symptoms, similar to other studies (Cellini et al., 2020). Family's daily routines were affected (Toran et al., 2021), including working at irregular times to meet childcare demands and limited social life (Cox and Olatunji, 2021). Around 1/4 of parents with children aged < 6 y reported food insecurity in their households (Karpman et al., 2020). The limited access to secure food threatened family health including sleep. Further, reduced access to medical care and mental healthcare might also impact parents' health and daily life (Sherman et al., 2020). Additionally, the loss of in-person contacts reduced caregivers' social support from extended family and friends. They struggled to manage several responsibilities as caregivers, providers, and educators together (Adams, 2020). Finally, family discord also rapidly increased during the pandemic (Campbell, 2020; Calvano et al., 2021). Some parents described parent-child relationships negatively in terms of conflicts, communication struggles, and boredom (Öngören, 2021). The disrupted daily life is more likely to be linked to an inconsistent connection with circadian entrainment cues and a weak relationship between bedtime and sleep. These in turn may relate to disrupted sleep and insomnia (Cox and Olatunji, 2021).

We acknowledge the presence of limitations in the current study. First, participants in this online study were recruited via social media. This might introduce a selection bias favored to female-dominated and educated populations who were using the internet frequently. Second, this was a cross-sectional study. Insomnia was not assessed prior to the pandemic. Third, the sample size of this subsample was relatively small. Fourth, as predictors of parental sleep, we did not assess the severity of young children's sleep disturbances and the co-morbidities of the children (e.g., autism spectrum disorder/attention-deficit/hyperactivity disorder or other medical conditions). Sleep disturbances in young children are highly prevalent. Parental sleep can be affected by the sleep patterns of their young child (Sinai and Tikotzky, 2012; Rönnlund et al., 2016; Staples et al., 2019). Lastly, we did not assess the specific changes to childcare during the pandemic. Parent sleep and mood may have been differentially impacted.

The insomnia symptoms were highly prevalent among parents and caregivers of young children. Sleep patterns, including sleep efficiency, markedly deteriorated from the patterns prior to the pandemic. The identified predictors associated with greater insomnia symptom severity and poor sleep efficiency included lower household income, greater depressive symptoms, poor sleep hygiene behaviors, altered sleep-wake routine, poor sleep efficiency before the pandemic, and greater COVID-related disruptions in daily life. Family-level and individual-level interventions are needed. First, additional childcare support for parents and caregivers to relieve caregiving stress should be provided. Second, mHealth-related approaches are generally accessible and can be practical interventions during pandemics. Third, public health education about promoting healthy sleep hygiene behaviors is also needed.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by the Institutional Review Board of Arizona State University. The patients/participants provided their written informed consent to participate in this study.

Conceptualization and methodology: NJ and MP. Data analysis, review, and editing: NJ, MP, and KP. Original draft preparation: NJ. Supervision: MP. All authors have read and agreed to the published version of the manuscript.