We all know that It is a common knowledge that many nights of poor, interrupted sleep is bad things for health. But what about a single night of sleep deprivation? Can it be as damaging? A new study finds that even one night of poor sleep can derail your health – putting your heart at risk. It can lead to an increased heart rate and blood pressure; and increased levels of stress hormones.
One 2008 study from the University of Chicago found a link between shortened sleep and increased coronary artery calcification (calcium deposits), “a good predictor of subsequent coronary artery disease,” says researcher Diane Lauderdale, PhD, professor of epidemiology at the university’s Pritzker School of Medicine. Lauderdale’s study also revealed that shorter sleep predicted worsening hypertension (high blood pressure). “For most people, blood pressure falls at night,” she says, “so it could be that with shorter sleep it’s just not enough for that dip to take place.
A good night sleep helps the body to repair itself through many mechanisms. For instance, when we are sleeping, there is a burst of important hormones required for growth, better immune function, metabolism, brain function and heart health. That’s why we wake up fresh, energetic and raring to go after a restful night.
Chronic sleep deprivation can send this ‘back-end’ growth, repair and maintenance process for a toss – leading to a snowballing effect on health. But this study highlighted that even short-term sleep disturbance can be harmful.
The researchers investigated a chosen team of 20 radiologists; with an average age of 31.6 years. The group was required to undergo cardiovascular magnetic resonance (CMR) imaging with strain analysis before and after they slept for an average of 3 hours over a 24-hour period. Interestingly, the effects of sleep deprivation on the heart function are not something previously examined using CMR strain analysis – considered the most sensitive parameter to gauge the ability of the cardiac muscle to contract.
Following a period of short-term sleep deficiency, the participants showed a significant increase in:
- Blood pressure and heart rate
- The levels of hormones; such as thyroid stimulating hormone (TSH), thyroid hormones FT3 and FT4, and cortisol (a stress hormone high levels of which are linked with cardiovascular risks.)
Part of the reason is that sleep’s effects on the heart are a relatively new area of study. Another is that measuring sleep is complicated. Many sleep studies rely on self-reporting, which may not always be accurate. Having your sleep measured objectively involves wearing an activity monitor, which “very likely changes your usual sleep,” Lauderdale says, “It’s pretty safe advice for the majority of people that sleeping less than six hours a night is probably not good.”
Dr. Daniel Kuetting, the study author from the Department of Diagnostic and International Radiology at the University of Bonn in Bonn, Germany, stressed that this study was intended to evaluate the real-time challenge faced by people today; most likely caused by work-related issues such as night shifts, longer shifts and work pressure. Variables like stress levels of the participants and environmental triggers were not factored in. More exhaustive studies – involving larger cohort groups – are required to understand the potential risks of long-term sleep loss.
Excessive workload, unrealistic deadlines and shift duration are changing (and dominating) the lifestyle dynamics today. In addition, some professions demand a 24-hour availability – for example, fire and emergency medical services – where sleep deprivation is a rule than the exception. Dr. Kuetting believes these findings will be useful to understand how these variables are affecting the public health, as reported in this latest public release.