WASHINGTON (dpa-AFX) - Irregular bedtimes in midlife may be a warning sign of higher cardiovascular risk, according to a new study from the University of Oulu. The research further suggests that large fluctuations in when people go to bed could double the risk of serious heart events, especially among those who sleep less than eight hours a night.
'Previous research has linked irregular sleep patterns to heart health risks, but this is the first time we've looked separately at variability in bedtime, wake-up time, and the midpoint of the sleep period-and their independent associations with major cardiac events,' said postdoctoral researcher Laura Nauha from the University of Oulu.
The study tracked 3,231 individuals born in Northern Finland in 1966. Researchers recorded their sleep patterns over one week at age 46 and then followed their health outcomes for more than a decade using healthcare registry data.
Findings showed that people with the most inconsistent bedtimes faced the highest risk, particularly if their average sleep duration was under eight hours. In this group, the likelihood of major cardiovascular events was about twice that of those with more regular sleep schedules. Interestingly, irregular wake-up times were not clearly linked to an increased risk.
Talking about keeping a heart-healthy routine, Nauha said, 'Maintaining a regular sleep schedule is one factor that most of us can influence.'
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