Sleep Disorders

Sleep Disorders

Millions of Indians are plagued by Sleep Disorders. It is a serious public health risk that too many doctors ignore. Half of Sleep Disorders consist of lack of sleep while other half consist of daytime sleepiness or over sleep. Sleep for certain hours is a compulsory physiological event of the brain for proper functioning of the body for remaining hours in 24 hours cycle. In 1953, it was discovered that sleep was actually comprised of two different states: non-rapid eye movement (NREM) and rapid eye movement (REM) Sleep.

Sleep Disorder Medicine

Sleep Disorder Medicine is a clinical specialty, which deals with diagnosis and treatment of patients who complain about disturbed nocturnal sleep, excessive daytime sleep and other sleep related problems. The most important clinical symptom in sleep disorder medicine is awareness of sleep related impaired alertness, in other words a complaint of excessive sleepiness. Important sleep disorder are, insomnia, sleep apnea syndrome, narcolepsy and parasomnias.

  • One-third of all Indians have some sleep problems.
  • 15 million Indians suffer from chronic insomnia
  • Another 10 million people suffer from sleep apnea
  • And over 2.5 lacs suffer from narcolepsy.

Sleep Apnea Syndrome

Sleep apnea is a syndrome that causes people to frequently stop breathing during sleep. As a result they fail to get the oxygen their body needs and restful night’s sleep. Sleep apnea is a serious condition; it can lead to increased risk of heart problem, excessive daytime sleepiness, decreased performance at work, memory loss and greater possibility of accidents. Sleep apnea affects about 3.5 per cent to 5 per cent population between the age group of 40-50 years. the condition is seen primarily in males over 40 years of age. Approximately 70 per cent of these people are obese. Patients often have short and thick neck, usually 17 inches or greater. Sleep apnea is a correctable health problem.

There are three types of sleep apnea encountered in clinical practice.

A. Obstructive Sleep Apnea: It is a most common type of sleep apnea and is caused by upper airway obstruction. The respiratory effort is present but there is no airflow at mouth. The site of obstruction is at the pharynx.

B. Central Sleep Apnea: It is the least common type of sleep apnea. In this there is failure of respiratory Center to send proper signals for breathing. In this type of apnea there is total absence of respiratory efforts and airflow at mouth.

C. Mixed Apnea: It is a combination of obstructive and central apnea.

Obstructive sleep apnea is caused by closure of upper airway anywhere between nasopharynx to hypopharynx. This is combined effect of structural and neuromuscular factor on the patency of upper airway. Main structural factors are

  • Narrow pharyngeal cavity from birth due to cranio-pharyngeal anomalies.
  • Fat deposition due to obesity.
  • Enlargement of tonsils and adenoids.


    A. Symptoms During Sleep

    Snoring: This is the main symptom of OSA and it is due to partial obstruction of airways. In early stage of disease snoring is loud and persistent while in advance stage it becomes intermittent with periods of silence due to frequent apneas

    • Abnormal movement
    • Disturbed sleep
    • Heavy sweating
    • Bed wetting and nocturia
    • Heartburn and acid reflux

    B. Daytime Symptoms

    Excessive Daytime Sleepiness: It may vary from fatigue and tiredness in mind cases, to excessive sleepiness with monotonous task such as watching TV and reading books. In severe cases patient goes to sleep while driving, eating or even writing. The exact cause of sleepiness is not known, but poor sleep in night due to frequent awakening, caused by hypoxia, hypercapnea or stimulation of mechanoreceptors may be one reason.

    • Irritability
    • Impaired concentration
    • Impaired memory and Judgment
    • Morning headaches
    • Sexual Problem
    • Personality changes

    Aggravating Factors for OSA

    • Alcohol
    • Hypnotics and Tranquilizers
    • Anesthesia
    • Partial sleep deprivation and shift work
    • Nasal obstruction and nasal allergies
    • Hypothyroidism
    • Obesity

      Lab Investigation

      1. Hemogram – Polycythemia indicates severe disease

      2. ECG and Echocardiogram – to find out evidence of PAH and ventricular hypertrophy due to systemic hypertension.

      3. Arterial blood gases – to assess the level of hyposia and hypercapnea

      4. Sleep Studies (clinical polysomnography)Polysomnography is defined as simultaneous recording, analysis and interpretation of large number of physiological parameters related to sleep. the various parameters recorded are: Pulse, Oxygen saturation, Respiratory volume, Snore index, Pressure, Flattening, Apnea index and apnea duration.

      This is the most important investigation to diagnose OSA. The apnea – hypopnea index which is defined as the total number of apnea and hypopnea divided by total number of hours of sleep. By this score we can assess the severity of disease. In the normal individual the score is less than 5 per hour or less than 30 in whole night. AHI more than 20 per hour indicate severe disease.

      The severity of OSA is also assessed by degree and duration of oxygen desaturation caused by apneas.

      Sleep studies (polysomnography) is also indicated in other sleep related disorders such as:

      1. Disturbances associated with medical, psychiatric and behavioral syndromes (insomnia, periodic limb movement, affective disorders)
      2. Sleep disorders in children
      3. Detection of respiratory failure in sleep and fall in oxygen saturation in patients suffering from COPD and other chronic respiratory.

      Dr. Mahesh Goyal, MD
      Jaipur Allergy and Asthma Centre,
      4, Park Street,
      MI Road, Jaipur.

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