This document discusses the differential diagnosis of sleep-related breathing disorders including obstructive sleep apnea syndrome (OSAS). It lists the diagnostic criteria for OSAS as loud snoring, intermittent pauses in breathing, sleep fragmentation, excessive daytime sleepiness, and upper airway narrowing. Some common symptoms are loud snoring, excessive daytime sleepiness, choking or shortness of breath at night, while less common symptoms include morning headaches, nocturnal sweating, and a spouse worried by apneic pauses.

1. Obstructive Sleep Apnea Syndrome Diagnosis

2. Differential diagnosis Sleep Related Breathing disorder A. Respiratory Center 1. Central sleep apnea syndrome 2. Ondine's Curse B. Reflex Peripheral 1. Benign snoring 2. Airway resistance syndrome 3. OSAS 4. Laryngospasm Excessive day time sleepiness 1. Narcolepsy 2. Periodic leg movements during sleep 3. Restless leg syndrome 4. Circadian rhythm disorder

3. Diagnostic Criteria OSAS 1. Loud snoring 2. Intermittent pause in respiration 3. Sleep Fragmentation 4. Excessive daytime sleepiness 5. Upper airway narrowing

4. Common symptom 1. Loud snoring 2. Excessive daytime sleepiness 3. Choking or shortness of breath at night 4. Restless sleep 5. Unrefreshing sleep 6. Changes in personality 7. Nocturia

5. Less common symptoms 1. Morning headache 2. Enuresis 3. Reduced libido 4. Spouse worried by apnoeic pauses 5. Nocturnal sweating

6. Rare symptoms 1. Recurrent arousals/ insomnia 2. Nocturnal cough 3. Symptomatic oesophageal reflux

7. Physical signs 1. Nasopharyngyeal narrowing 2. BMI > 28Kg/m2 ; nuchal obesity (M:F:: 17”:16”) 3. Posterior cross-bite, anterior open-bite and lip-incompetence. 3. Systemic hypertension 4. Pulmonary hypertension and corpulmonale (rare)

8. Benign snoring Prevalence 20% Sex M>F (4:6) Age 35-65y Predisposing factors Overweight Large tonsils Nasal obstruction Nasal congestion A small receding chin Sleeping on the back Alcohol Sleeping tablets

9. Upper airway resistance syndrome Effort of breathing increased No apnea, hypoxemia Sleep fragmentation without waking Excessive daytime sleepiness

10. Laryngospasm A sudden, prolonged, forceful apposition of the vocal cords A laryngeal reflex-response to noxious stimuli Stomach acid and a high airflow rate Less than a minute in duration

11. Central sleep apnea syndrome Respiratory center failure in sleep Less common then OSAS Associated with Cardiac and Neurological disorder Sleep fragmentation and hypoxemia Excessive daytime sleepiness

12. Ondine’s curse Central hypoventilation syndrome Respiratory center failure during sleep Die immediately after birth without treatment

13. Narcolepsy Excessive daytime sleepiness Abnormal REM sleep Sleep paralysis, cataplexy and hypnagogic hallucinations Fragmented nighttime sleep with frequent awakenings

14. Periodic leg movements in sleep Insomnia Excessive daytime sleepiness Frequent awakenings from sleep, Unrefreshing sleep

15. Restless Leg Syndrome Creeping or crawling sensations in the legs An irresistible urge to move the affected extremity Relief of the symptoms by walking A worsening of the symptoms when the afflicted person is at rest

16. Circadian Rhythm Disorder Common in night shift workers A. Delayed sleep phase syndrome Difficulty in falling asleep and getting up B. Advance sleep phase syndrome Early falling asleep and waking up