A bevy of research has shown a link between sleep deprivation and cardiovascular disease, metabolic disorders, and obesity.
However, it''s been unclear why sleep loss might lead to these effects. Several studies have tested the effects of total sleep deprivation, but this model isn''t a good fit for the way most people lose sleep, with a few hours here and there.
In a new study by Keith Pugh, Shahrad Taheri, and George Balanos, all of the University of Birmingham in the United Kingdom, researchers test the effects of partial sleep deprivation on blood vessels and breathing control.
They find that reducing sleep length over two consecutive nights leads to less healthy vascular function and impaired breathing control.
Following the first two nights of restricted sleep, the researchers found a significant reduction in vascular function compared to following the nights of normal sleep. However, after the third night of sleep restriction, vascular function returned to baseline, possibly an adaptive response to acute sleep loss, study leader Pugh explained.
In other tests, the researchers exposed subjects to moderately high levels of carbon dioxide, which normally increases the depth and rate of breathing. However, breathing control was substantially reduced after the volunteers lost sleep.
The researchers later had these volunteers sleep 10 hours a night for five nights. After completing the same tests, results showed that vascular function and breathing control had improved.
Pugh noted that the results could suggest a mechanism behind the connection between sleep loss and cardiovascular disease.
"If acute sleep loss occurs repetitively over a long period of time, then vascular health could be compromised further and eventually mediate the development of cardiovascular disease," he said.
Similarly, the loss of breathing control that the researchers observed could play a role in the development of sleep apnea, which has also been linked with cardiovascular disease.
Pugh added that some populations who tend to report sleeping shorter periods, such as the elderly, could be at an even higher risk of these adverse health effects.