The University of Oulu in Finland explored how inconsistent sleep schedules relate to heart health in middle-aged adults. The findings were shared through the Journal of Activity Sedentary and Sleep Behavior (JASSB).
Approximately 3,700 volunteers with an average age of 46 took part. Participants filled out health and lifestyle questionnaires and underwent a clinical examination assessing body weight, blood pressure, lipid levels, and an oral glucose tolerance test. Wrist-worn activity trackers measured daily activity and sleep patterns, providing objective data alongside self-reported information.
On average, the group reported going to bed around 11 p.m. and waking around 7 a.m., spending roughly eight hours in bed. For about half of the participants, bedtimes, wake times, and time in bed fluctuated by at least one hour per week, on average.
The researchers found that irregular bedtimes were associated with a higher risk of cardiovascular disease and with larger waist circumferences among the participants. These associations persisted after accounting for various lifestyle and health factors, suggesting that sleep regularity itself may play a role in cardiovascular risk profiles.
Earlier research has indicated a link between breathing patterns during sleep and memory function, highlighting how sleep quality can influence cognitive outcomes. This study adds another dimension to the importance of maintaining regular sleep schedules for overall health.