Approximately 50-70 million people in the United States are chronic sufferers from sleep disorders. These people have impaired health and daily functioning issues as a result of those disorders. The societal economic impact of sleep disorders is estimated at $16 billion annually for health care expenses and $50 billion annually regarding lost productivity.
Sleep disorders are considered to be one of the most common health problems, and yet it has been demonstrated that between 82 and 98% of adults with sleep-related breathing disorders (SRBD) are undiagnosed.
Sleep disorders can no longer be thought of in simple terms as having a poor night’s sleep. There are presently a large number of different sleep disorders that may affect one’s quality of life. Plus, there is a difference between the sleep state and the wake state. Sleep is not simply an altered state of consciousness, that is merely a difference of being asleep or being awake.
Sleep is a totally separate behavioral and physiological state that is unique and well documented, and it is defined as “a reversible behavioral state of perpetual disengagement from and unresponsiveness to the environment.”
Sleep is composed of a combination of rapid eye movement (REM) and nonrapid eye movement (NREM) associated with well-defined and variable brain activity. Sleep disruption and the specifically recognized sleep disorders can have a major impact on an individual’s well-being, health stratus and quality of life. Plus, may also give significant consequences on the various areas of public health, such as accidents, morbidity, mortality, work and other daily performance , cognitive function and utilization of health care.
EPIDEMIOLOGY OF SLEEP DISORDERS
Epidemiology is the branch of medicine that deals with the incidence, distribution, and possible control of diseases and other factors relating to health.
Currently the most common sleep disorders on the basis of epidemiologic studies are the following:
- Sleep related breathing disorders (SRBD)
- Restless leg syndrome (RLS)
The general onset of sleep disorders can be dependent on age, the presentation of being at risk for health-related consequences, and trauma. In many examples, these disorders may appear as a health issue and perhaps even some type of psychological or emotional condition. Plus, the presentation of the particular health issue is sometimes not first recognized or diagnosed as maybe having an association with a sleep disorder. For example, a SRBD patient may seek treatment and utilize more health care resources for cardiovascular disease or diabetes prior to the recognition of the SRBD as being the possible underlying cause.
There are many risk factors that may influence the onset as well as the progression of a specific sleep disorder. The risk factors may be different for each disorder, and there can be overlapping risk factors that apply to a number of different sleep disorders. The demands of modern-day life have impacted the quality of ones sleep as well as the required amounts that are believed appropriate. Plus, the disruption of and individual’s sleep can impact other family members, sleep partner or roommates. As an example, in some studies, the snoring of one person significantly impacted the sleep of the bed partner to the point that the affected person had symptoms that were worse than those of the snorer.
Common risk factors for the three most common sleep disorders.
Sleep apnea and sleep-related breathing disorders:
- Increases with age
- Snoring/gasping during sleep-related
- Associated with larger neck sizes
- Increase with weight
- Males greater than females
- Coexisting cardiovascular disease or hypertension
- Airway obstruction-especially tonsils and elongated soft palate
- Large adenoids
- Enlarged tongue
- Allergy or asthma
- Family history
- Increases with age
- Associated with anxiety and /or depression
- Females greater than males
- Associated with pain, headaches, arthritis, temporomandibular disorder symptoms
- Dissatisfied with one’s quality of sleep
- Substance abuse
- Perceives health as worse or bad
Restless legs syndrome:
- Increases with age
- Worsens over time-follows a chronic course
- Males greater than females
- Use of antidepressants
- Low iron levels
- Peripheral neuropathy
- End stage renal disease
- May coexist with sleep bruxism
HEALTH CONSEQUENCES AND COSTS
The impact of sleep disorders on one’s health can be evident in a wide range of adverse health problems, including but not limited to:
- Cardiovascular diseases
- Metabolic disorders
- Gastroesophageal reflux disease
- Psychological and emotional disorders
- Increased mortality rates.
The increased awareness that assorted health issues potentially may appear as a result of sleep disorders is improving.
The increased risk for cardiovascular disease and elevated blood pressure associated with SRBD are very well-documented. The largest and frequently cited investigation, the Sleep Heart Health Study, took place between 1995 and 1998. This was a cohort study with more than 6000 people enrolled as participants. This study showed that obstructive sleep apnea (OSA) along with other SRBD are risk factors for cardiovascular disease, which is inclusive of heart attack and stroke. Several proposed mechanisms indicate that OSA and cardiovascular disease are related with elevated blood pressure is the more common one.
Insomnia, which is the inability to fall asleep or to maintain sleep, is often associated with emotional, psychological, or depressive disorders. Furthermore, it can be associated with painful conditions as well as other health issues. As a sleep disorder, insomnia is the most common and may occur in conjunction with other sleep disorders such as OSA and restless leg syndrome. Everyone may have insomnia at some point in their life.
Alteration in endocrine and metabolic functions is also associated with SRBD, the most prevalent of which is type 2 diabetes. It has been shown that snoring alone raises the risk for type 2 diabetes independent of any other risk factors.
Although sleep disorders can potentially increase the risk for a multitude of health problems, it is not an absolute that a given sleep disorder will lead to any one specific health problem. The important issue is to know that these health problems may have an underlying sleep disorder as a contributing factor in the development or progression of a health issue.
Common health issues possibly associated with a sleep disorder:
- Morning Headaches
- Cardiovascular disease
- Anxiety or depression
- Gastroesophageal reflux disease
There are also associations of sleep disorders with deficiencies in performance relative to attention and reaction time, which can have significant impact in work settings or operating a vehicle. One study demonstrated that about 20% of serious injuries from motor vehicle accidents are related to driver sleepiness and not alcohol-related. Other reports have indicated the equivalence of driving when sleepy (drowsy driving) as when driving under the influence of alcohol.
A report by the National Sleep Foundation (NSF) indicated that:
- 60% of adult drivers stated that they have driven a vehicle during the past 12 months while feeling drowsy
- 37% self-reported that they fell asleep while driving at leasr1-2 days/month.
The NSF report included an estimate by the National Highway Traffic Administration that vehicular crashes related to driver fatigue result in a minimum estimation of $12.5 billion of monetary losses to the economy. Financial impact on society could be higher since there is no physical test to attribute these crashes to sleepiness.
Studies have also shown the association of sleep-related fatigue and work-related injuries and fatalities. Workers who were identified as highly fatigued had a 70% greater chance of being involved in occupation-related accidents than were workers identifies with low fatigue. Another study demonstrated that workers with insomnia had a greater chance for injuries related to occupations than workers who were identified as having a good sleep. Plus, workers with disturbed sleep had twice as much chance of dying in a work-related accident than those who did not have sleep disturbance.
Because of the increased risk for the development of health problems with sleep disorders, there may be an associated increase in health care costs as well. The presence of a sleep disorder may drive up the cost of health care in general, and it has been estimated that untreated sleep apnea may add $16 billion in medical costs annually in the United States.
However, at the present time, it is unclear what the actual savings in medical costs are with the management of OSA. In one study, thirty-one patients that were diagnosed with cardiovascular disease and OSA, there was a reduction in the need for hospitalization related to the cardiovascular illness when the apnea was adequately managed. Thus, an association amid the severity of the sleep disorder and increased health care expenditures is possible.
The costs of health care is increased by the lack of regard to the specific sleep disorder. A 1998 study demonstrated that 10 years prior to the actual diagnosis of OSA, the patients who were eventually diagnosed with OSA had acquired nearly double the costs for health care and had additional hospitalizations when compared to the control patients. In some instances, the sleep disorder literally precedes the onset of the specific health issue or consequence. Usually, if the sleep disorder is not discovered, then the attention to the health-related issue takes precedent. This may then lead to an increase in expenditures for various testing, physician visits, imaging, hospitalization and medication or prescription usage.
Along with health issues that may arise, there is also the impact on one’s quality of life. Research that measured parameters regarding quality of life demonstrated that patients with a sleep disorder feel that their quality of life is poorer than those without OSA. When the OSA is improved with treatment, both the patient and the bed partner experience and improvement in their quality of life.
THE ROLE OF THE DENTIST
As it relates to the recognition of health issues, the role of the dentist as well as the auxiliary staff is becoming more apparent. No longer is the dentist merely relegated to only the management of dental structures and dental-related conditions.
In the past, the dentist’s role in the overall health care of the patient was initiated by performing blood pressure screenings. Patients often saw their dentist more frequently than they saw their physician. The blood pressure screenings led to the discovery that many patients were at risk for hypertension and yet were unaware of its existence.
The role of the dentist can potentially take one of two roles:
The first, referred to as the indirect approach, is simply the recognition of the potential existence of a sleep disorder that may be interfering in the patient’s health status, and the patient is subsequently advised of the situation and referred for definitive evaluation and care.
The second, referred to as the direct approach, is when a sleep disorder is recognized and, if appropriate, the patient is referred for more comprehensive evaluation and care. This testing often involves the primary care physician and/ or sleep specialist, and the care, when deemed applicable, may also include the dentist. The dental treatment typically involves the use of a custom oral appliance for the management of OSA. This oral appliance brings the jaw downward and forward opening up the airway.
The dentist now has an expanding role in the recognition of a patient who may be at risk for a sleep disorder. Epidemiologic data support the increasing awareness of the relationship of sleep disorders and other health issues.