The Accreditation Council for Graduate Medical Education announced that maximum shifts for first-year doctors will be extended from 16 consecutive hours to 24 hours starting July 1, 2017. Because doctors and many health professionals are already sleep-deprived and overworked, this begs the question: what do longer consecutive hours on shift, and consequently less sleep, mean for the human body?
There are two main types of sleep: rapid-eye-movement (REM) and non-rapid-eye-movement (NREM) sleep. REM sleep is considered “active sleep” due to its characteristic low-amplitude, high-frequency alpha waves and eye movements. NREM sleep is split into three stages, with the first stage N1 being the first seven minutes of dozing off and the final stage N3 considered “deep sleep.” Throughout the night, one cycles through these stages, spending more time in N3 deep sleep as the night progresses. The recommended amount of sleep for an adult is between 7-9 hours, according to the Journal of the National Sleep Foundation.
But what happens when one sleeps fewer than the recommended number of hours?
Image source: Paul Bradbury
If the sleep deprivation is acute or the patient has restricted sleep for several consecutive nights, the effects are minimal. One study found that acute sleep deprivation led to lower global cognitive function, or the ability to perform mental operations, especially in regards to motor skills and higher-order cognitive functions.
But if the sleep deprivation is chronic, the effects are much more devastating. Studies show that sleep deprivation can be linked to obesity and diabetes due to higher glucose levels and high blood pressure over time, which in turn can lead to heart disease, kidney disease, and even strokes. Aside from physical consequences, sleep deprivation can also affect mood and mental health — those with insomnia (one cause of chronic sleep deprivation) are five times more likely to develop depression and anxiety.
Not only does the number of hours of sleep affect performance, but waking and sleeping times also greatly affect functional ability. Just this month, a study was published that showed increased performance and functioning of university students when allowed to start their workday later at 9:30 AM rather than at 8 AM. This research has moved schools to start classes at 9 AM globally, particularly in the United States and South Korea.
Hence, it is truly ironic that though doctors have at one point in their schooling studied the importance of sleep for the body’s cognitive function, they remain some of the most sleep deprived and exhausted professionals in the world. According to the AAA Foundation for Traffic Safety, drivers who only sleep for five or six hours in a 24-hour period are twice as likely to crash as those who got seven hours of sleep or more. Would you trust a doctor with fewer than seven hours of sleep to operate on you?
Feature Image Source: MKDigitalArt