Objective: To examine whether nocturnal sleep duration and daytime napping are related to overweight/obesity among adults in Chengdu City.
Methods: A total of 1276 adults( women 823, men 453) aged 20-70 years were selected by randomized cluster sampling in 2015. The sleep duration rounded up to the hour was determined according to the answer to the question, "How much time do you usually sleep per night?", the nap time of subjects were collected according to the answer by the question, "How many days do you have a nap in a week?". Height and weight were measured to calculate body massindex. Logistic regression models were used to estimate the odd ratio( OR) and 95%confidence interval( 95% CI) of overweight/obesity.
Results: Approximately 66. 38% of subjects had daytime napping habit. After adjustment for potential confounders, OR( 95% CI) of overweight/obesity was 0. 69( 0. 54 - 0. 88) for nap takers compared with individuals without daytime napping habit. One nap increase in a week was associated with-0. 20, -0. 13 BMI in young adults and middle-aged adults. Very short nocturnal sleep duration( < 6 hours) and short nocturnal sleep duration( 6-6. 9 hours) was significantly associated with an increased risk of overweight/obesity among middle-aged adults OR = 2. 11( 95% CI 1. 20-3. 76), OR = 1. 93( 95% CI 1. 13-3. 34).
Conclusion: The frequency of daytime napping was negative associated with BMI among young and middle-aged adults. Short nocturnal sleep duration was associated with higher risk of overweight/obesity among middle-aged adults in Chengdu.
Keywords: adult; daytime napping habit; nocturnal sleep duration; overweight/obesity.