Sleep characteristics vary between populations. Detrimental sleep habits have cognitive consequences leading to daytime functioning debilitation. Until now no study has been done to investigate sleep characteristics in Iran thoroughly. In this study, we aimed to evaluate Iranians' sleep characteristics and their association with daytime functioning. We conducted a population-based study from January 2017 to May 2019 on people more than 18 years old who lived in 11 urban destricts and 3 rural areas of Tehran, Iran. We randomly selected the participants using a multistage random stratified clustered sampling method. We obtained the participants' demographic and anthropometric characteristics and details of bedtime, sleep duration, sleep onset latency, wake-up time and sleep impact on daytime functioning. Logistic regression model was used to assess the relationship between sleep characteristics) and daytime functioning. In total, 1830 people with a mean age of 40.83 years participated in the study. The gender distribution of the participants was even, and 70.98% of them were married. After adjusting for age and sex, the following three factors had a significant impact on daytime functioning: bedtime, sleep onset latency, and sleep duration. (OR = 1.12, P < 0.038, OR = 1.01, P < 0.011, and OR = 0.99, P = 0.01, respectively). We also found that longer sleep onset latency (P = 0.004) and shorter sleep durations (P = 0.029) significantly interfere with daytime functioning. Iranians' sleep characteristics, especially their sleep duration and sleep onset latency, are associated with their daytime function. Interventions on people's sleep hygiene are warranted to promote healthier sleep behaviors among Iranians, considering the high impact of current sleep characteristics on their daily lives.
© 2022. The Author(s).