The following signs and symptoms are associated with either obstructive or central sleep apnea:

• Hypersomnia or excessive daytime sleepiness
• Periodic breathing cessation during sleeping
• Vascular headache in the morning
• Loud snoring
• Periods of awakening during sleep coupled with shortness of breath
• Insomnia (difficulty in staying asleep)
• Difficulty in focusing and maintaining attention

The diagnosis of sleep apnea may be effectively clinched with a detailed clinical history. Patients may still be subjected to some tests that may ascertain the diagnosis of sleep apnea. The following tests or sleep studies are implored to patients suspected of having sleep apnea:

• Nocturnal polysomnography: This device records the lung, heart, and brain activities during sleep. Breathing patterns are graphed while nocturnal patterns of arm and leg movements are also recorded [8]. The blood oxygen levels are also measured during the test process to assess the presence of sleep apnea.
• Home sleep test kits: These test kits are very similar to the nocturnal polysomnograph, although heart rate, breathing patterns, airflow, and blood oxygen saturation are the only parameters which are being measured.

The milder forms of sleep apnea may only require some lifestyle modifications. However, some forms of sleep apnea like those classified under moderate and severe may need other treatment options for its resolution. The following therapy and treatment modalities are implored in the treatment of sleep apnea:

• Continuous positive airway pressure (CPAP): This is an oxygen delivery system through a mask which is placed over the nose during sleep. The airflow through the mask creates a positive pressure slightly greater than the environmental pressure making the airways continually open during the duration of the sleep [9].
• Adjustable airway pressure device: This system is very similar to CPAP, it only self-adjusts so that the air pressure becomes high during inhalation and subsequently drops during expiration.
• Expiratory Positive Airway Pressure (EPAP) – This device allows airflow to freely go in during inhalation but diverts airflow through a network of smaller holes during expiration making the expiratory phase create a positive pressure to the upper airways.
• Uvulopalatopharyngoplasty: This is a surgical procedure used to remove soft tissue structures like the tonsils and the adenoids to clear the airways and allay the symptoms of sleep apnea [10].
• Tracheostomy: This is a surgical procedure used when all other methods fail. A hole is created through the neck and trachea for easier respiration during sleep. This procedure is indicated for patients with severe sleep apnea, with associated life threatening conditions.

The common symptoms of sleep apnea like daytime sleepiness and snoring are considered to be a benign complication with a very excellent prognosis. A cohort study, implicated severe untreated sleep apnea to increase the mortality rate of myocardial infarction and stroke among Spanish patients [6]. Australian studies on moderate to severe sleep apnea among men have suggested a significant increase in mortality rate among the respondents [7].

The obstructive type of sleep apnea occurs when the posterior muscles of the larynx relaxe and obstruct the airways during sleep. When the airways constrict during inspiration the blood oxygen levels significantly drop during sleep. The most common causes of the central sleep apnea are heart failure and cerebrovascular diseases (stroke). People suffering from central type of apnea are more likely to remember their apneic spells than those with the obstructive type of apnea.

In the United States, an estimated 18 million people are suffering from either forms of sleep apnea. Although a great majority of these people remain underdiagnosed or undiagnosed. The prevalence rate of sleep apnea is estimated to be 4% among the male population and 2% among women [2]. Recent studies have seen an increasing incidence of sleep apnea in the younger age group especially among obese children.

Internationally, sleep apnea occurs infrequently among the English population with only 3 cases per 1000 population. Higher prevalence rates of obstructive sleep apnea are observed among Australians and Israeli population which reach up to 25%. The elderly population beyond the age of 65 years has a two to three fold risk of developing sleep apnea than their middle aged counterpart [3]. The relatively high fat distribution over the neck among males make them more predisposed to sleep apnea compared to women with a prevalence ratio of up to 3:1 internationally [4].

The upper airway is a slender and compliant tube that could collapse inward when the laryngeal muscles relax during sleep [5]. The intraluminal pressure may not be always greater than the transluminal pressure during sleep; thus, the propensity for collapse and narrowing of the airways is a frequent event. The pharyngeal space where the airway constricts is bounded by the soft palate, the back of the tongue, and the parapharyngeal fat pads. Any pathology that decreases this space consequently increases the risk of sleep apnea.

Sleep apnea is closely associated with obesity; thus, efforts to reduce weight through regular exercise and a healthy diet may significantly lower the risk for sleep apnea. Alcohol and certain medications (tranquilizers) must be avoided to prevent the throat muscles from relaxing during sleep. Try to sleep on one side rather than full supine to prevent the tongue and soft palate from falling towards the throat causing obstruction. Smoking must be avoided for this worsens oxygen saturation in the blood.

Sleep apnea or obstructive sleep apnea (OSA) is a potentially serious sleeping disorder where the breathing intermittently stops and starts for a period of time. Patients usually snore and complain of tiredness even after a full night sleep. There are essentially two types of sleep apnea, the obstructive type of sleep apnea, and the central type of sleep apnea. The obstructive type is fairly common and is characterized by the relaxation of the throat muscle during sleep [1]. The central type is evident when the brain fails to transmit the proper signals to the muscles of respiration that gives rise to apnea. Patients suffering from sleep apnea should seek medical attention promptly to avoid untoward complications in the future.

Definition

Sleep apnea is a common clinical condition where the breathing may suddenly stop or become too shallow during sleep.

Cause

The causes of sleep apnea vary, and they might include the internal processes that happen in our body like relaxation of the throat muscles during sleep, any obstruction in the upper airways, and concomitant medical illness like heart problems and stroke.

Symptoms

The symptoms of sleep apnea include snoring, daytime sleepiness, difficulty in maintaining sleep at night, headaches, and difficulty in maintaining focus.

Diagnosis

The diagnosis of sleep apnea is mainly by the use of a nocturnal polysomnography and home sleep test kits.

Treatment

The treatment of sleep apnea has wider options that include CPAP, adjustable airway devices, EPAP, uvulopalatopharyngoplasty, and tracheostomy.

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