Date post: | 15-Jul-2015 |
Category: |
Health & Medicine |
Upload: | dr-arun-mathai-mani |
View: | 20 times |
Download: | 0 times |
LEEP DISORDERS
What is sleep?
• Complex physiological state that occurs periodically and is characterised by relative quiescence, immobility and greatly decreased responsiveness to external stimuli
Sleep Stages
• based on EEG, EOG, EMG divided into two independent states: NREM and REM sleep
• NREM - further divided into three stages ieN1, N2, N3 – based on EEG
Sleep Requirements
• Sleep requirement is defined as the optimal amount of sleep required to remain alert and fully awake and to function adequately throughout the day
• for an average adult is approximately 7.5 to 8 hours
Classification of Sleep Disorders
• I. Insomnia
• II. Sleep-related breathing disorders
• III. Hypersomnias of central origin
• IV. Circadian rhythm sleep disorders
• V. Parasomnias
• VI. Sleep-related movement disorders
Approach to the Patient
Common sleep complaints
• Insomnia - inability to initiate or maintain sleep adequately at night
• EDS - chronic fatigue, sleepiness, or tiredness during the day
• Inability to sleep at the right time
• Abnormal movements and behavioural manifestation associated with sleep
SUBJECTIVE MEASURES OF SLEEPINESS
Narcolepsy
• characterized by recurrent "sleep attacks"• Irresistible desire to fall asleep in inappropriate
circumstances and at inappropriate places• last for a few minutes to as long as 20 to 30
minutes
Narcolepsy TetradSleep Attacks plus 3 specific symptoms:
1. Cataplexy sudden weakness or paralysis without loss of consciousness, often precipitated by emotional changes
2. Hallucinations at sleep onset (hypnagogic hallucinations) or upon awakening(hypnopompic hallucinations)- most common is visual
3. Sleep paralysis occurs near sleep onset or during arousal. Consciousness is maintained.
Narcolepsy
• Symptoms of narcolepsy typically begin in the second decade
• Once established, the disease is chronic without remissions
• Men and women are equally affected• affects about 1 in 4000 people in the United
States
GENETICS & PATHOGENESIS
• Most are sporadic, some are AD
• positivity for HLA DQB1*0602 – most specific marker
• Dysfunction of hypothalamic hypocretin(orexin) peptidergic system is involved in the pathogenesis
• decreased hypocretin 1 in CSF < 110pg/ml
Treatment of Narcolepsy-CataplexySyndrome
Nonpharmacological measures include
• scheduled short daytime naps,
• sleep hygiene measures
Breathing-related Sleep Disorders
syndromes in which the patient's sleep is interrupted by problems with his or her
breathing
OBSTRUCTIVE SLEEP APNEA
• MC medical condition @ EDS
• defined as the coexistence of unexplained EDS with at least five obstructed breathing events (apnea or hypopnea) per hour of sleep
• repetitive episodes of complete (apnea) or partial (hypopnea) upper airway obstruction during sleep
• arterial oxygen desaturation and arousal from sleep
Apnea-Hypopnea Index (AHI)
• number of apneas and hypopneas per hour of sleep
• AHI score of 5 or below is considered normal
• 5 to 15 - mild OSAS
• 16 to 29 - moderate OSAS
• 30 or more - severe OSAS
Pathogenesis
• Collapse of the pharyngeal airway is the fundamental factor
• During sleep, muscle tone decreases-increasing upper airway resistance and narrowing the upper airway space
Epidemiology
• prevalence is 4% in men and 2% in women between the ages of 30 and 60
• also occurs in childhood—usually associated with tonsil or adenoid enlargement
Symptoms & Signs
Consequences
• increased morbidity and mortality
• short-term consequences (impairment of quality of life and increasing traffic- and work-related accidents)
• long-term consequences from associated and comorbid conditions such as systemic hypertension, pulmonary hypertension, heart failure, cardiac arrhythmias
General Measures
• Avoid alcohol and sedative-hypnotics, especially in the evening
• Reduce body weight if overweight
• Avoid sleep deprivation
• Participate in regular exercise program
• Avoid supine sleeping position
Mechanical Devices
• Continuous positive airway pressure (CPAP) titration - treatment of choice
• Oral appliances, including mandibular advancement device
• Tongue-retaining device
Surgical Techniques
• Uvulopalatopharyngoplasty (UPP)
• Laser-assisted UPP (LAUP)
• Radiofrequency UPP (somnoplasty)
• Palatal implants
• Nasal surgery
• Maxillomandibular advancement
• Anterior hyoid advancement
• Tonsillectomy and adenoidectomy
PARASOMNIAS
• abnormal movements or behaviours that occur in sleep or during arousals from sleep
ICSD-2 (AASM, 2005)
Disorders of arousal (from NREM sleep),
• Confusional arousals
• Sleepwalking
• Sleep terror
Parasomnias associated with REM sleep
• RBD
• Recurrent isolated sleep paralysis
• Nightmare disorder
Other Parasomnias
Sleepwalking
• Onset: common between ages 5 and 12 yr
• Abrupt onset of motor activity arising out of slow-wave sleep during first one-third of the night
• Duration: less than 10 min
• Injuries and violent activity occasionally reported
• Treatment: benzodiazepines, imipramine
Sleep Terror• pavor nocturnus
• Onset: peak is between ages 5 and 7 yr
• Abrupt arousal from slow-wave sleep during first one-third of the night, with a loud piercing scream
• Treatment: psychotherapy, benzodiazepines, tricyclic antidepressants
Rapid Eye Movement SleepBehavior Disorder (RBD)
• Onset: middle-aged or elderly men
• Presents with violent dream-enacting behavior during sleep, causing injury to self or bed partner
• 40% idiopathic, 60% associated neurodegenerative diseases - PD, MSA, CBD, DLBD, PSP
• Treatment: clonazepam, melatonin
Nightmare Disorder
• Dream anxiety attacks
• fearful, vivid, often frightening dreams, mostly visual but sometimes auditory
• most commonly occur during the middle to late part of sleep at night
• mostly a normal phenomenon, up to 50% of children have nightmares
• side effects of certain medications such as antiparkinsonian drugs (pergolide, levodopa), anticholinergics, and antihypertensive drugs, particularly beta-blockers
• generally do not require any treatment except reassurance
Sleep-Related Movement Disorders
Restless Legs Syndrome (RLS)
• also known as Ekbom’s syndrome
• Unpleasant sensations in the legs when the patient is tired in the evenings and at the onset of sleep
• ameliorated by moving the legs• mostly diagnosed in the middle or later years• strong familial tendency • can present with daytime somnolence due to
disturbed night-time sleep
Secondary - Medical Disorders
• Anemia: iron and folate deficiency
• Diabetes mellitus
• Amyloidosis
• Uremia
• Chronic obstructive pulmonary disease
• Peripheral vascular (arterial or venous) disorder
• Rheumatoid arthritis
• Hypothyroidism
Pathophysiology
• iron-dopamine dysfunction
• abnormalities in the body’s use and storage of iron
• dopamine dysfunction - changes in dopamine receptors or dopamine uptake
Drug Treatment of RestlessLegs Syndrome
Dopaminergic agents:
• Pramipexole
• Ropinirole
Benzodiazepines:
• Clonazepam
• Temazepam
Antiepileptic agents:
• Gabapentin
• Pregabalin
Insomnia
• most common sleep disorder
• Inability to initiate or maintain sleep, early awakening, inadequate sleep time, or poor sleep quality associated with a lack of feeling restored and refreshed in the morning, leading to poor daytime functioning - AASM (2005)
Medical Disorders Comorbidwith Insomnia
• Ischemic heart disease
• Congestive cardiac failure
• Chronic obstructive pulmonary disease
• Bronchial asthma
• Peptic ulcer disease
• Gastroesophageal reflux disease
• Rheumatic disorders
Treatment of Insomnia
• most commonly used hypnotics are the benzodiazepine receptor agonists – zolpidem,zaleplon, and eszopiclone
• Melatonin receptor agonists(ramelteon) -sleep-onset insomnia
Laboratory Assessment ofSleep Disorders
• The two most important laboratory tests for diagnosis of sleep disturbance are PSG and the MSLT
• overnight PSG study is the single most important laboratory test for the diagnosis and treatment of patients with sleep disorders
• EEG, EMG, EOG, ECG, SaO2, Nasal and oral airflow, Respiratory effort (chest and abdomen)
Multiple Sleep Latency Test
• important test to effectively document EDS
• Narcolepsy is the single most important indication
• presence of two sleep-onset REMs on four or five nap studies and sleep-onset latency of less than 8 minutes strongly suggest a diagnosis of narcolepsy
• circadian rhythm sleep disturbance - REM sleep abnormalities