Sleep Disorders Overview
A sleep disorder, or somnipathy, is a medical disorder of the sleep patterns of a person or animal. Some sleep disorders are serious enough to interfere with normal physical, mental, social and emotional functioning
Sleep problems, including snoring, sleep apnea, insomnia, sleep deprivation, and restless legs syndrome, are common. Good sleep is necessary for optimal health and can affect hormone levels, mood and weight.
Is a medical specialty or subspecialty devoted to the diagnosis and therapy of sleep disturbances and disorders. From the middle of the 20th century, research has provided increasing knowledge and answered many questions about sleep-wake functioning. The rapidly evolving field has become a recognized medical subspecialty in some countries.
Sleep dentistry (Dental sleep medicine)
Dentists are more concerned about sleep-related breathing disorders (Bruxism, snoring and sleep apnea), Dental sleep medicine also qualifies for board certification in some countries. Properly organized, minimum 12-month, postgraduate training programs are still being defined in the United States, they are organized in the Academy of Dental Sleep Medicine (USA). The qualified dentists collaborate with sleep physicians at accredited sleep centers and can provide oral appliance therapy and upper airway surgery to treat or manage sleep-related breathing disorders.
Sleep apnea is a type of sleep disorder characterized by pauses in breathing or instances of shallow or infrequent breathing during sleep. Each pause in breathing, called an apnea, can last from at least ten seconds to several minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally shallow breathing event is called a hypopnea. Sleep apnea is often diagnosed with an overnight sleep test called a polysomnogram, or "sleep study".
There are three forms of sleep apnea: central (CSA), obstructive (OSA), and complex or mixed sleep apnea (i.e., a combination of central and obstructive) constituting 0.4%, 84% and 15% of cases respectively. In CSA, breathing is interrupted by a lack of respiratory effort; in OSA, breathing is interrupted by a physical block to airflow despite respiratory effort, and snoring is common.
Regardless of type, an individual with sleep apnea is rarely aware of having difficulty breathing, even upon awakening. Sleep apnea is recognized as a problem by others witnessing the individual during episodes or is suspected because of its effects on the body (sequelae). Symptoms may be present for years (or even decades) without identification, during which time the sufferer may become conditioned to the daytime sleepiness and fatigue associated with significant levels of sleep disturbance.
Common Side Effects of Sleep Apnea
Common effects of sleep apnea include daytime fatigue, a slower reaction time, and vision problems. Moreover, patients are examined using “standard test batteries” in order to further identify parts of the brain that are affected by sleep apnea. Tests have shown that certain parts of the brain cause different effects:
- The “executive functioning” part of the brain affects the way the patient plans and initiates tasks.
- Second, the part of the brain that deals with attention causes difficulty in paying attention, working effectively and processing information when in a waking state.
- Thirdly, the part of the brain that uses memory and learning is also affected. Due to the disruption in daytime cognitive state,
Behavioral effects are also present. This includes moodiness, belligerence, as well as a decrease in attentiveness and drive.
Another symptom of sleep apnea is waking up in sleep paralysis. In severe cases, the fear of sleep due to sleep paralysis can lead to insomnia. These effects become very hard to deal with, thus the development of depression may transpire.
There is also evidence that the risk of diabetes among those with moderate or severe sleep apnea is higher.
There is also increasing evidence that sleep apnea may also lead to liver function impairment, particularly fatty liver diseases.
Stop Breathing during sleep causes a buildup of carbon dioxide in the blood. The heart then begins to pump harder to try to remove the carbon dioxide from the blood. This adds a great deal of stress on the heart when it occurs repeatedly, which will increase the risk of:
- Blood pressure/ hypertension
- Pulmonary hypertension
• Accidents at work
• Accidents while Driving
Finally, because there are many factors that could lead to some of the effects previously listed, some patients are not aware that they suffer from sleep apnea and are either misdiagnosed, or just ignore the symptoms altogether.
Diagnosis of sleep apnea
As Dentists we can be the first one to know if a patient has an obstructive sleep apnea, by noticing his oral anatomy, like having a large tonsils, a large tongue, or a small jaw bone, and as we provide our dental services, we can notice if the patient has short breathes and can’t breathe well in a supine position, also patients with clenching or Bruxism most probably will have sleep apnea disorder, from these small notices we can advice the patients to do further investigations, so we can be the first one to notice this problem when he himself has no idea he has a problem, and thus we can save his life.
The definite diagnosis of sleep apnea is based on the conjoint evaluation of clinical symptoms (e.g. excessive daytime sleepiness and fatigue) and of the results of a formal sleep study (polysomnography, or reduced channels home based test). The latter aims at establishing an "objective" diagnosis indicator linked to the quantity of apneic events per hour of sleep (Apnea Hypopnea Index(AHI), or Respiratory Disturbance Index (RDI)
One example of a commonly adopted definition of an apnea (for an adult) includes a minimum 10 second interval between breaths, with either a neurological arousal (a 3-second or greater shift in EEG frequency, measured at C3, C4, O1, or O2) or a blood oxygen desaturation of 3–4% or greater, or both arousal and desaturation.
Obstructive Sleep Apnea
Obstructive sleep apnea. Sleeping during airway obstruction at the palate, tongue and epiglottis. Oxygen is labeled with blue arrows and carbon dioxide is labeled with yellow arrows. Note that oxygen cannot enter below the obstruction and likewise carbon dioxide cannot escape.
Obstructive sleep apnea (OSA) is the most common category of sleep-disordered breathing. The muscle tone of the body ordinarily relaxes during sleep, and at the level of the throat the human airway is composed of collapsible walls of soft tissue which can obstruct breathing during sleep. Mild occasional sleep apnea, such as many people experience during an upper respiratory infection, may not be important, but chronic severe obstructive sleep apnea requires treatment to prevent low blood oxygen (hypoxemia), sleep deprivation, and other complications.
The risk of OSA rises with increasing body weight, active smoking and age. In addition, patients with diabetes or "borderline" diabetes have up to three times the risk of having OSA.
Snoring is a common finding in people with this syndrome, the loudness of the snoring is not indicative of the severity of obstruction, however. If the upper airways are tremendously obstructed, there may not be enough air movement to make much sound. Even the loudest snoring does not mean that an individual has sleep apnea syndrome. The sign that is most suggestive of sleep apneas occurs when snoring stops.
It has been revealed that people with OSA show tissue loss in brain regions that help store memory, thus linking OSA with memory loss. Using magnetic resonance imaging (MRI), the scientists discovered that sleep apnea patients' mammillary bodies were nearly 20 percent smaller, particularly on the left side. One of the key investigators hypothesized that repeated drops in oxygen lead to the brain injury.
Central sleep apnea
In pure central sleep apnea or Cheyne–Stokes respiration, the brain's respiratory control centers are imbalanced during sleep. Blood levels of carbon dioxide, and the neurological feedback mechanism that monitors them; do not react quickly enough to maintain an even respiratory rate, with the entire system cycling between apnea and hyperpnea, even during wakefulness. The sleeper stops breathing and then starts again. There is no effort made to breathe during the pause in breathing: there are no chest movements and no struggling. After the episode of apnea, breathing may be faster (hyperpnea) for a period of time; a compensatory mechanism to blow off retained waste gases and absorbs more oxygen.
Physiologic effects of central apnea: During central apneas, the central respiratory drive is absent, and the brain does not respond to changing blood levels of the respiratory gases. No breath is taken despite the normal signals to inhale. The immediate effects of central sleep apnea on the body depend on how long the failure to breathe endures. At worst, central sleep apnea may cause sudden death. Short of death, drops in blood oxygen may trigger seizures, even in the absence of epilepsy. In people with epilepsy, the hypoxia caused by apnea may trigger seizures that had previously been well controlled by medications. In other words, a seizure disorder may become unstable in the presence of sleep apnea. In adults with coronary artery disease, a severe drop in blood oxygen level can cause angina, arrhythmias, or heart attacks (myocardial infarction). Longstanding recurrent episodes of apnea, over months and years, may cause an increase in carbon dioxide levels that can change the pH of the blood enough to cause a metabolic acidosis.
We can see how sleep apnea can be dangerous to our patients, so I feel it’s not optional to learn about this topic it’s our duty.