SEATTLE, WA—Older adults who spend a longer time in bed were found to have less sleepiness than those who spent an average time in bed, according to data from a study presented at SLEEP 2015.
Earlier epidemiological studies had shown that retrospective self-reported long sleep duration was tied to negative health effects. The effects of these over a 2-week period is not as clear and so Cody M Havens, BS, from the Department of Psychology, University of Arizona, Tucscon, AZ, and colleagues sought to answer whether “symptoms of sleepiness fatigue differ in older adults who spend more time in bed vs. those who spend an average amount of time in bed.” The team initially hypothesized that adults who sleep longer would have greater sleepiness and fatigue than average sleepers.
A total of 37 older women and 11 men were recruited for the study. An actigraphy was conducted to determine their 2-week median time in bed (TIB). An “average TIB” was defined as 6–7.25 hours, and “long TIB” was defined as 8–9.25 hours.
Patients were excluded if any of the following conditions were present: inflammatory disorders, substance abuse, shift work, excessive napping, excessive TIB not trying to sleep (>30 minutes), obstructive sleep apnea (pAHI >15), bipolar disorder, current cancer, heart attacks, sleeping pills, current smoking, and BMI ≥35.
Havens and colleagues discovered that older adults with long TIB actually experienced less sleepiness than adults with average TIB; this was not at clinically significant levels. However, “no differences in fatigue were observed between the two groups,” he added.
Average TIB resulted in significantly greater sleepiness (6.27±3.34) than long TIB (4.10±3.64); this was associated with a moderate effect size (P<0.04). Average TIB also lead to greater fatigue (14.95±11.72) than adults with long TIB (12.26±11.46); this difference was not significant (P=0.46) and was associated with a small effect size.
Study findings suggest that more time in bed may lower daytime sleepiness. Havens noted, “Our ongoing study will better address causality by exploring whether changing TIB has an effect on these measures.”