Importance of Getting Zs

Does your work or home schedule keep you up late? Do you feel like you rarely get enough sleep? Research shows that not getting enough sleep can increase your risk of heart disease. It’s time to make sure you’re getting the sleep you need. Even if you can’t change your work time or schedule, there are steps you can take.

Adults need between 7 and 9 hours of sleep. If you’re not getting enough sleep, you may be increasing your heart disease risk, according to new research in the American Heart Association journal Hypertension.

The Study

To determine the impact of circadian rhythm (about 24-hour) disturbances on cardiovascular function in sleep-deprived people, researchers studied 26 healthy people ages 20 to 39. The study participants were:

  1. Restricted to five hours of sleep for eight days (sleep restriction) with fixed bedtimes (circadian alignment) OR
  2. Restricted to five hours of sleep for eight days (sleep restriction) with bedtimes delayed by 8.5 hours on four of the eight days (circadian misalignment).

In the study, sleep restriction (five hours of sleep) with delayed bedtimes was associated with:

  • Increased heart rate during the day for fixed bedtimes and delayed bedtimes groups and even more so at night when sleep restriction was combined with delayed bedtimes.
  • Reduced heart rate variability at night.
  • Increase in 24-hour urinary norepinephrine excretion in the sleep-restricted, delayed-bedtime group. Norepinephrine is a stress hormone that can constrict blood vessels, raise blood pressure and expand the windpipe.

What it Means to You

In humans almost all physiological and behavioral processes follow a circadian rhythm that is regulated by an internal clock located in the brain. When our sleep-wake and feeding cycles are not in tune with the rhythms dictated by our internal clock, a disruption occurs.

Study results suggest shift workers, who are chronically exposed to insufficient sleep patterns, might not fully benefit from the restorative cardiovascular effects of nighttime sleep following a shift-work rotation.

Shift workers often find it challenging to balance sleep and activities with their varying shifts. Shift workers often find there is not enough time between each shift to sleep and spend time with their friends or families before they have to get ready for their next shift.

Social opportunity and work demand have caused people to become more active during late evening hours leading to a shift from a daytime lifestyle to a more nocturnal one. Exposure to consecutive days of sleep loss can impair cardiovascular function and these negative effects might be enhanced when changes in feeding and/or sleep-wake habits lead to a circadian disruption.

Since shift work often cannot be avoided, researchers encourage a healthy diet, regular exercise and making sleep a priority.

Source: American Heart Association News