Increased TV viewing time is associated with less sleep and more sleep difficulties in a large population-based cohort

Abstract

TV watching before bedtime is often discouraged in sleep recommendations. However, there has been limited epidemiological evidence on how TV viewing time might influence different aspects of sleep, especially among the older population. We aim to explore the cross-sectional relation between TV viewing time and sleep in an ageing British population. Data were drawn from the European Prospective Investigation into Cancer and Nutrition (EPIC-Norfolk) study. During 2006–2007, 5475 men and women reported daily TV viewing time and at least one of the sleep measures: time spent in bed, sleep duration, difficulty getting to sleep at night, waking up during night or in early morning and trouble getting back to sleep. Sleep efficiency was defined as the ratio of sleep duration and time in bed. Participants were categorized into four physical activity levels based on a physical activity questionnaire during the same period. On average, participants spent 8.63 h (standard deviation [SD] = 0.85) in bed and slept for 6.93 h (SD = 1.10) per night. 47% of the participants reported difficulty getting to sleep, and more than 65% reported the other two difficulties. Those in the highest quartile (4–9 h/d) compared to the lowest quartile of TV watching time (0–2 h/d) spent longer time in bed at night ( ¦ Â=0.22 [95%CI 0.17, 0.27]), slept for shorter hours ( ¦ Â = −0.18 [−0.24, −0.12]), and had lower sleep efficiency (OR = 0.54[0.48, 0.61]). They also reported higher prevalence of difficulty in getting to sleep (OR = 2.05[1.83, 2.30]), waking up during the night (OR = 1.54 [1.36,1.73]) or in early morning (OR = 1.61[1.43,1.81]) and trouble getting back to sleep. These associations remained after further adjustment for age, sex, social class, education, smoking, alcohol intake, hypnotic drug use, depression, Body Mass Index and physical activity ( p < 0.001). The adjusted ORs associated with long TV viewing time for higher sleep efficiency (>= 80%) and difficulty falling asleep were 0.70 (0.59–0.84) and 1.78 (1.50–2.11), respectively. The above associations seemed stronger among those who were most physically active, though the interaction was not significant. Physical activity was not associated with the sleep measures. TV viewing is associated with impaired sleep quality. Further longitudinal study is needed to examine the direction of the relationship. EPIC-Norfolk study was supported by the Medical Research Council, UK(G9502233, G0300128) and Cancer Research, UK (C865/A2883).