Clinical Sleep Disturbances
Fatigue and alertness can also be affected by the presence of various biological and physiological conditions that affect sleep and wakefulness. The disturbances in sleep and wakefulness associated with working irregular hours are not considered biological or clinical disturbances of sleep. These pathological disturbances in sleep and wakefulness must meet various diagnostic criteria in order to qualify as clinical conditions.
There are several different types of sleep disturbance: insomnia, which refers to too little sleep; hypersomnia which refers to too much sleep; and parasomnia which refers to deviation from normal sleep patterns. Some authorities estimate that about one third of the population suffers from disturbed sleep (Bixler, Kales, Soldatos, Kales, & Healy, 1976; Liljenberg, Almquist, Hetta, Roos, Agren, 1988)
According to these specialists, in order to meet the criteria of chronically disturbed sleep a person must suffer some form of sleep disturbance at least every other day for a period of three weeks. These disturbances must involve either taking to much time to fall asleep (more than 45 minutes), repeated waking (more than 5 times per night), waking up too early (more than 60 minutes) or getting one and a half hours less than the required 8 hours of sleep. Moreover, any of these symptoms must also be accompanied by disturbances in performance or daytime functioning.
Insomnia is present in about 5 to 6 percent population. In most cases insomnia is thought to be the result of learned psychological responses. Persons suffering from insomnia often report high levels of anxiety associated with worries, traumatic events, or prolonged stress from work or other sources. Depression is another common source of disturbed sleep. Depressed patients often report obtaining less sleep, have difficulty falling asleep, intermittent awakening, and early morning waking. Treatment usually involves some form of psychological intervention including cognitive restructuring and relaxation training.
Hypersomnia, the desire for more sleep, usually manifests itself as a difficulty in staying awake. Criteria for diagnosing this condition are a consistent inability to remain awake in typical everyday situations such as traveling as a passenger in a car, watching TV, listening to a lecture, or reading a newspaper. Common causes of hypersomnia that have received increased attention recently are snoring and sleep apnea which both have excessive sleepiness as associated symptoms.
Approximately 30 percent of men and 20 percent of women experience snoring. Recent studies have demonstrated that snoring reduces both the quality and duration of sleep as a result of short periods of waking and the condition has also been connected to the occurrence of high blood pressure. It is hypothesized that sleep apnea is the result of temporary blockage of the respiratory pathway due to excess fatty tissue in the throat or a relaxation muscles of the throat. When the person has difficulty breathing a startle response occurs causing the person to momentarily wake up to get air. Interestingly, the person is unaware of the recurrent awakening that occurs throughout the sleep period. Unfortunately, the repeated awakenings reduce deep sleep and REM sleep. REM sleep (Rapid Eye Movement) is a recurring portion of a normal sleep pattern associated with dreaming and believed to restore brain function. A person suffering from sleep apnea experiences extreme tiredness during the day. Recent research has begun to look at the relationship between sleep apnea and involvement in accidents.
There are several treatments for sleep apnea and excessive snoring. Sleeping on ones side can reduce snoring and sleep apnea. Surgery can be used to remove obstructions. Weight loss may aid in decreasing the amount of fatty tissue in the throat. Another treatment is the wearing of an appliance in the mouth to keep the airway open. Known as CPAP, continuous airway pressure, the procedure has been shown to be successful.
Parasominas are disturbances during sleep, which disrupt but do not prevent sleep. The most common are nightmares, sleep walking, and bruxism or gnashing of teeth.
While these disorders are not the result of working in a railroad environment the co-occurrence of these disorders in conjunction with an irregular working schedule found in railroad settings may perhaps lead to increased risk for performance decrements. Consequently, railroad companies have sought to engage in identification of persons with sleep disorders to minimize the likelihood of problems arising.
Insomnia
Insomnia is estimated to affect more than half of the U.S. adult population. Insomnia can take many different forms: difficulty falling asleep or staying asleep, waking up too early, or waking up feeling unrefreshed. In a survey by the National Sleep Foundation, 58% of adults reported having insomnia at least a few nights a week. And the vast majority of those surveyed agreed that sleep loss can have a major impact on their lives (www.shuteye.com)
Sleep Apnea
Obstructive sleep apnea (OSA) is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses and closes during sleep. In central sleep apnea, the airway is not blocked but the brain fails to signal the muscles to breathe. Mixed apnea, as the name implies, is a combination of the two. With each apnea event, the brain briefly arouses people with sleep apnea in order for them to resume breathing, but consequently sleep is extremely fragmented and of poor quality.
Sleep apnea is very common, as common as adult diabetes, and affects more than twelve million Americans, according to the National Institutes of Health. Risk factors include being male, overweight, and over the age of forty, but sleep apnea can strike anyone at any age, even children. Yet still because of the lack of awareness by the public and healthcare professionals, the vast majority remain undiagnosed and therefore untreated, despite the fact that this serious disorder can have significant consequences.
Untreated, sleep apnea can cause high blood pressure and other cardiovascular disease, memory problems, weight gain, impotency, and headaches. Moreover, untreated sleep apnea may be responsible for job impairment and motor vehicle crashes. Fortunately, sleep apnea can be diagnosed and treated. Several treatment options exist, and research into additional options continues. http://www.sleepapnea.org/info/index.html
Restless Leg Syndrome
In order for you to be officially diagnosed with RLS, you must meet the criteria described in the four bullets below.
- You have a strong urge to move your legs which you may not be able to resist. The need to move is often accompanied by uncomfortable sensations. Some words used to describe these sensations include:creeping, itching, pulling, creepy-crawly, tugging orgnawing.
- Your RLS symptoms start or become worse when you are resting. The longer you are resting, the greater the chance the symptoms will occur and the more severe they are likely to be.
- Your RLS symptoms get better when you move your legs. The relief can be complete or only partial but generally starts very soon after starting an activity. Relief persists as long as the motor activity continues.
- Your RLS symptoms are worse in the evening especially when you are lying down. Activities that bother you at night do not bother you during the day.
If you do have restless legs syndrome (RLS), you are not alone. Up to 10% of the U.S. population may have this neurologic condition. Many people have a mild form of the disorder, but RLS severely affects the lives of millions of individuals. http://www.rls.org/NetCommunity/Page.aspx?&pid=200&srcid=184
Sleep Disorder Clinics
{PARAGRAPH}
