Michigan State University’s Sleep and Learning Lab has conducted one of the largest sleep studies to date, revealing that sleep deprivation affects us much more than prior theories have suggested.
Published in the Journal of Experimental Psychology: General, the research is not only one of the largest studies, but also the first to assess how sleep deprivation impacts placekeeping – or, the ability to complete a series of steps without losing one’s place, despite potential interruptions.
This study builds on prior research from MSU’s sleep scientists to quantify the effect lack of sleep has on a person’s ability to follow a procedure and maintain attention.
“Our research showed that sleep deprivation doubles the odds of making placekeeping errors and triples the number of lapses in attention, which is startling,” Fenn said.
“Sleep-deprived individuals need to exercise caution in absolutely everything that they do, and simply can’t trust that they won’t make costly errors. Oftentimes – like when behind the wheel of a car – these errors can have tragic consequences.”
By sharing their findings on the separate effects sleep deprivation has on cognitive function, Fenn – and co-authors Michelle Stepan, MSU doctoral candidate and Erik Altmann, professor of psychology – hope that people will acknowledge how significantly their abilities are hindered because of a lack of sleep.
“Our findings debunk a common theory that suggests that attention is the only cognitive function affected by sleep deprivation,” Stepan said.
“Some sleep-deprived people might be able to hold it together under routine tasks, like a doctor taking a patient’s vitals. But our results suggest that completing an activity that requires following multiple steps, such as a doctor completing a medical procedure, is much riskier under conditions of sleep deprivation.”
This study builds on prior research from MSU’s sleep scientists to quantify the effect lack of sleep has on a person’s ability to follow a procedure and maintain attention.
The researchers recruited 138 people to participate in the overnight sleep assessment; 77 stayed awake all night and 61 went home to sleep.
All participants took two separate cognitive tasks in the evening: one that measured reaction time to a stimulus; the other measured a participant’s ability to maintain their place in a series of steps without omitting or repeating a step – even after sporadic interruptions.
The participants then repeated both tasks in the morning to see how sleep-deprivation affected their performance.
“After being interrupted there was a 15% error rate in the evening and we saw that the error rate spiked to about 30% for the sleep-deprived group the following morning,” Stepan said. “The rested participants’ morning scores were similar to the night before.
“There are some tasks people can do on auto-pilot that may not be affected by a lack of sleep,” Fenn said. “However, sleep deprivation causes widespread deficits across all facets of life.”
Sleep loss from various causes is prevalent and often missed by physicians as a treatable health problem. There are strong associations with serious medical conditions such as diabetes mellitus & insulin resistance, hypertension, obesity, obstructive sleep apnea, depression, and anxiety.
These medical and psychiatric comorbidities put a person at risk for heart attack and stroke. Other adverse consequences of chronic sleep loss on public health include increased mortality & morbidity, poor performance on waking activities resulting in increased accidents & injuries, lower self-reported quality of life, decreased family well-being, and reduced use of health care. It is clear that sleep loss has a profound effect on human health and well-being. Quantity and quality of sleep play an essential role in mental & physical health and merit consideration in any treatment plan.
Etiology
Sleep loss has many causes and is generally multifactorial. Common contributing causes of sleep loss are sleep apnea, insomnia, restless leg syndrome, parasomnias, mood disturbances, psychosis, and other psychiatric, neurological, & medical conditions. When assessing the cause(s) of sleep loss, it is essential to address any of these underlying factors directly. Providers should not treat symptoms if they identify an underlying treatable cause. If the provider is unable to identify any contributing factors, the default diagnoses are primary insomnia.
Primary insomnia is most common in elderly populations. As people age, the sleep architecture changes; delta-wave (or deep) sleep decrease, and the proportion of time spent in lighter sleep increases; this results in increased sleep disruptions.[1]
The duration of sleep also decreases with age. Comorbid medical conditions can be both the cause and the effect of chronic sleep loss. For instance, a patient can develop obesity, which results in obstructive sleep apnea. The lack of quality sleep then leads to increased serum cortisol levels, which facilitates further weight gain. Go to:
Epidemiology
Sleep loss is a pervasive problem that increases in frequency as individuals age. As the proportion of geriatric persons increases in the population in the U.S. and worldwide, the prevalence of sleep disorders will increase. Other causes of sleep loss, such as obesity, which leads to obstructive sleep apnea, are also on the rise.[2][3] Studies have found that sleep loss is more common than previously thought. Estimates are that 50 to 70 million Americans suffer from some form of sleep loss.[4]
The drivers behind the recently increased prevalence of sleep loss include several broad societal changes, including working longer hours, shift work, and having greater access to television & the internet. Adults today are sleeping less to get more work done and staying up late to watch TV or use the Internet. A recent study found in people ages 25 to 45 years old, 20% were consistently sleeping 90 minutes less than was needed to maintain good health. [5]
The problem of inadequate sleep is likely to increase due to our society’s 24/7 nature, with activities to do at all hours and increased access to night time use of computers, mobile phones, and television. Studies have found that there has been a decline in the amount of sleep of up to 18 minutes per night over the last three decades.[6][7] Epidemiological studies may inaccurately depict this problem as data is collected by self-report methods, which do not differentiate between time asleep and time in bed. Polysomnography is accurate but is expensive and time-consuming to utilize in extensive epidemiological studies. A new, cheaper method to collect data on sleeping habits involves the use of actigraphy.[8]
Pathophysiology
Chronic sleep deprivation has significant adverse effects on health and overall quality of life. Chronically sleep-deprived individuals had significantly lower reported markers of quality of life on a 36-item survey.[1] The survey looked at areas one’s ability to function throughout the day, health problems, perception of pain, the general perception of one’s health & vitality, social functioning, and mental health.
Interestingly, many conditions that are commonly comorbid with sleep deprivation are associated with similar physiological states. Chronic sleep deprivation is associated with elevated cortisol and decreased testosterone levels. Testosterone is known to enhance the function of the gamma-aminobutyric acid (GABA) and serotonin systems in the brain. This reduced function provides one possible causal link between two of the most commonly associated psychiatric disorders, depression, and anxiety. Also, elevated serum cortisol levels have correlations with depression, anxiety, hypertension, obesity, and diabetes type II. Chronic sleep deprivation correlates with increased inflammatory markers, which is associated with all the above-mentioned comorbid conditions and psychosis.
It is essential to realize that the body has many of the same physiological markers in chronic sleep deprivation as it does with its many comorbid conditions. Many of these physiological states provide the causal link between sleep deprivation and these other psychiatric and medical conditions. This cause and effect relationships are reciprocal, making chronic sleep deprivation a potential cause and result of these other conditions. It is of paramount importance to ensure a patient is getting adequate quality sleep when treating these conditions.
History and Physical
It is vital to assess a person’s quality and quantity of sleep. Seven to eight hours and nine hours of sleep are generally ideal for adults and adolescents, respectively. Less sleep correlates with obesity, diabetes & impaired glucose tolerance, cardiovascular disease & hypertension, anxiety and depressive symptoms, and alcohol use.[1] The presence of these ailments could serve as indicators that a patient may have an impaired quality of sleep. As a rule of thumb, the sicker the patient, the less likely it is that the patient sleeps well.
When taking a history, essential questions to ask to assess a patient’s sleep are:
Do you have trouble falling asleep? Staying asleep? Do you feel tired upon waking from sleep?
If the patient answers affirmatively to any of these questions, follow up with: Do these problems with sleep occur despite adequate time and opportunity for rest? Is the sleep difficulty impairing your functioning during the day? Do you feel distressed from the lack of quality sleep?
It is also essential to make an inquiry regarding the severity and frequency of these symptoms.[1] A patient who lacks adequate sleep will commonly endorse symptoms of sleep loss, such as excessive daytime sleepiness, poor concentration, fatigue, moodiness, and decreased libido, among other symptoms.[9] Be sure to optimize the patient’s sleep before focusing on symptom relief. Again, correct the cause, not the symptom.
Evaluation
Upon determination of the poor quality of sleep, further evaluation is needed to determine potential causes of sleep loss. There will generally be more than one cause contributing to the loss of sleep. It is better to treat the causes directly. If obstructive sleep apnea (OSA) is a cause of quality sleep loss, it is best to address this with CPAP and/or weight loss. Ignoring the contribution of OSA to the sleep disturbance and prescribing sedating sleep aids could worsen the OSA and quality of sleep. It is also important to identify the symptoms the patient may be experiencing from sleep loss. The symptoms the patient suffers from should be monitored to assess treatment progress. The most common symptom of sleep loss is excessive daytime sleepiness. Also, patients can display depressed mood, poor focus, and impaired memory. Lack of sleep can also exacerbate psychiatric and medical conditions such as OSA, obesity, hypertension, depression, anxiety, etc. Lack of sleep will impair executive functions.[10] After optimizing sleep by addressing all the contributing factors, it is crucial to re-evaluate the patient for residual symptoms. At this time, symptomatic relief can be the focus.
Treatment / Management
Despite the significant toll sleep loss places on public health, it is not often addressed by clinicians. To date, there are no formal treatment guidelines. However, there are many effective ways to treat sleep loss.
Treatment for sleep consists of three general approaches:
- Behavioral modification/improving sleep hygiene
- Treating causative medical and psychiatric conditions
- Pharmacotherapy
It is important to review proper sleep hygiene with the patient to eliminate behavioral habits that adversely affect sleep. As mentioned previously, many of the comorbid medical and psychiatric conditions can be contributing to the trouble with sleep. The individual treatments for all these comorbidities are beyond the scope of this article. If the first two treatment options fail to resolve the sleep difficulties, one can consider pharmacotherapy. The clinician should be judicious when using medications as sleep aids because they can have unintended adverse effects. Certain medications can worsen daytime fatigue if given at too high a dose or if the medication half-life is too long. Sedating sleep aids can also exacerbate the conditions causing poor sleep. OSA can be worsened by sleep aids that promote weight gain and further relax the muscles around the airway during rest.
If sleep loss is a result of a lifestyle that cannot be changed (e.g., shift work), the provider can address excessive daytime sleepiness by giving specific behavioral tips to help individuals stay alert. Medications that promote wakefulness, such as caffeine, modafinil, and methylphenidate, are options. Currently, modafinil is the only medication that is FDA approved for shift work sleep disorder, but not sleep loss.[11]
Differential Diagnosis
Sleep loss is a symptom, and to appropriately treat it, it is vital to discern between the many potential causes, which include:
- Primary insomnia
- Depression
- Anxiety
- Obstructive sleep apnea
- Obesity
- Substance abuse
- Chronic pain
Conditions that can mimic the symptoms of sleep loss are:
- Chronic fatigue syndrome
- Narcolepsy
- Substance abuse
- Depression
- Anxiety
Prognosis
If a healthcare provider appropriately identifies sleep loss, treatment can be successful, and the patient can resume a healthy lifestyle.
Complications
Lack of adequate sleep can lead to many complications. Some of these complications can lead to further difficulty in getting sleep. Lack of sleep causes elevated cortisol, which can result in increased blood sugar, increased blood pressure, cravings for carbohydrates, and sugar, which leads to weight gain and other medical and psychiatric complications. The subjective experience of sleep loss can be distressing, which can exacerbate complications. The following is a non-comprehensive list of complications of sleep loss:
- Diabetes/insulin resistance
- Hypertension
- Obesity
- Obstructive sleep apnea
- Vascular disease
- Stroke
- Myocardial infarct
- Depression
- Anxiety
- Psychosis
Deterrence and Patient Education
The best preventive treatment is patient education. Once a person understands the importance and methods of quality sleep, rest will most likely become a higher priority. Patient education should include proper sleep hygiene and other common causes of poor sleep. It is crucial to assess the patient’s current sleep habits and identify what they are doing right and areas where they can improve. Encourage a healthy lifestyle, which will result in better overall health, which will lessen the chances the patient will develop medical conditions that will affect sleep.
Source:
Michigan State Universityr
Media Contacts:
Caroline Brooks – Michigan State University
Image Source:
The image is in the public domain.
Original Research: Closed access
“Effects of total sleep deprivation on procedural placekeeping: More than just lapses of attention”. Stepan, Michelle E., Altmann, Erik M., & Fenn, Kimberly M.
Journal of Experimental Psychology: General doi:10.1037/xge0000717.
