Sleep during COVID-19 pandemic: Longitudinal observational study combining multisensor data with questionnaires

The COVID-19 pandemic led to various containment strategies, such as work-from-home policies and reduced social contact, which significantly altered people's sleep patterns. Our study, conducted from June 2021 to June 2022, longitudinally examined the changes in the sleep patterns of working adults in Finland during this period, utilizing multisensor data from fitness trackers and monthly questionnaires. We conducted a comprehensive study, exploring the changes in sleep patterns in correlation with multiple factors such as individual demographics, occupation, sleep-related behaviors, levels of physical activity, restrictions imposed by the pandemic, and adjustments in seasonal variations. From over 27,000 nights analyzed from 112 participants, we found a correlation between stringent pandemic measures and increased total sleep time as well as delayed sleep timing. Academic staff experienced shorter and more variable sleep durations compared to service staff. Early-day physical activity was also linked to longer sleep duration, revealing the influence of lifestyle on sleep quality. Habitual snoozers exhibited higher variability in their sleep patterns. The findings reveal the multifaceted impacts of the pandemic and associated measures on sleep patterns, highlighting the nuanced variations among different occupations and habits, and emphasizing the role of flexible work-life routines and external factors in shaping sleep behaviors during such unprecedented times.