Prevalence of short and long sleep duration: Ravansar NonCommunicable Disease (RaNCD) cohort study

Background Prevalence of short and long sleep duration varies in different countries and changes over time. There are limited studies on Iranians' sleep duration, and we aimed to evaluate the prevalence of short and long sleep duration and associated factors among people living in Kermanshah, Iran. Methods This population-based cross-sectional study was conducted between November 2014 and February 2017. Data was collected from 10,025 adults aged 35 to 65 years using census sampling, and we evaluated the short and long sleep duration (<= 6 and >= 9 h, respectively) and its relation with the socio-demographic factors and health-related status of the participants. Results Mean age of participants was 48.1 years (standard deviation = 8.2), and 47.4% of participants were male. Of our participants, 11.6% had short, and 21.9% had long sleep duration. Age >= 50 years, female gender, being single, mobile use for longer than 8 h per day, working in night shifts, moderate and good levels of physical activity, BMI >= 30, past smoking, and alcohol use were associated with short sleep duration (P < 0.05). Female gender and living in rural areas were associated with long sleep duration (P < 0.05). Conclusion In the Ravansar population, short and long sleep duration are prevalent, with long sleep duration having higher prevalence. People at risk, such as night shift workers, as well as modifiable factors, such as mobile phone use, can be targeted with interventions to improve sleep hygiene.