Study Notes on Sleep Disorders

Sleep Disorders

Insomnia

• Definition: Insomnia refers to the inability to fall asleep or to maintain sleep throughout the night.
• Types of Insomnia:
  • Acute Insomnia: Lasts less than 3 months.
  • Chronic Insomnia: Persists for more than 3 months.
• Potential Causes:
  • Emotional problems
  • Pain conditions
  • Underlying physical disorders
  • Use or withdrawal from drugs
  • Excessive alcohol consumption in the evening, which can shorten sleep and lead to withdrawal effects.

Factors Contributing to Sleep Deficiency

• Sleep Apnea:
  • Characterized by interruptions in the supply of oxygen during sleep, causing the individual to awaken intermittently.
  • Increases the risk of various health issues including:
  • Hypertension
  • Myocardial infarction
  • Stroke
  • Arrhythmias
  • Heart failure
  • Diabetes
  • Obesity
• Restless Legs Syndrome: A condition characterized by an uncontrollable urge to move one’s legs.
• Caffeine Consumption: From sources such as coffee, tea, and cola, which can interfere with sleep quality.
• Medications: Both prescription and non-prescription drugs may contribute to insomnia.
• Chronic Illnesses: Conditions such as gastroesophageal reflux disorder, angina, and chronic pain can lead to sleep disturbances.

Sleep Requirements Across Ages

• The amount of sleep necessary varies significantly:
  • Infants: Up to 16 hours per day.
  • Teenagers: Require approximately 9 hours.
  • Adults: Function well on 5 to 8 hours.
  • Elderly: Typically need shorter sleep durations and experience lighter sleep with less dreaming.
  • Associated Factors: Sleep duration tends to be linked to:
  • Increasing age
  • Psychiatric or medical conditions
  • Certain medications

Importance of Sleep

• Sleep is essential for various biological and physiological functions, such as:
  • Proper functioning of the immune system.
  • Maintaining a healthy nervous system.
  • Supporting emotional and social functioning.
  • Enhancing physical and mental agility.
  • Improving memory.

The Sleep Cycle

• The sleep cycle is governed by circadian rhythms, which are biological changes that follow a time cycle.
• Circadian Rhythms:
  • Driven primarily by external cues such as sunlight, which influence the pineal gland.
  • The Pineal Gland plays an important role in releasing melatonin, a hormone that induces drowsiness and helps regulate body temperature and hormone secretion.

Sleep Hygiene Recommendations

• ** Practices Patients Should Follow**:

  • Maintain a consistent sleep schedule, waking up at the same time every day (include weekends).
  • Increase exposure to bright light during daytime.
  • Establish a regular activity routine and refrain from exercising late in the evening.
  • Create a relaxing bedtime routine and a comfortable sleep environment (e.g., warm bath, quiet, dark room, cooler temperature).
  • Use the bed solely for sleep and/or sexual activities.
  • Power down electronic devices at least 30 minutes prior to sleep.

• Practices Patients Should Avoid:

  • Napping, unless working shifts.
  • Consumption of caffeine, nicotine, and other stimulants, especially in the afternoon or evening.
  • Alcohol consumption, particularly before bedtime.
  • Exposure to bright lights at night.
  • Engaging in exercise within 3 hours of bedtime.
  • Eating large or heavy meals within 3 hours of bedtime.
  • Maintaining extreme temperatures in the bedroom.
  • Frequently checking the time.
  • Consuming excessive fluids before bed.

Non-Pharmacologic Treatments for Sleep

• Reference to textbook for comprehensive list.

Pharmacologic Treatment for Insomnia

• Indication: Recommended only for short-term use to facilitate sleep.
• Goal: To induce drowsiness to help individuals drift off to sleep (improve sleep latency) and to promote sustained sleep (improve sleep maintenance).

Herbal Treatments for Insomnia

• Melatonin: A hormone produced by the pineal gland, sensitive to light, signaling the body to prepare for sleep.
• Valerian Root: A herbal remedy used for sleep issues for over 2000 years, known for its sedative properties.
• Caution: Some herbal treatments may interact with various medications, leading to significant side effects.

Sedatives and Hypnotics

• Classes of Drugs:
  • Benzodiazepines: Examples include temazepam and triazolam.
  • Benzodiazepine receptor agonists: Include eszopiclone, zolpidem, and zopiclone.
• Distinction: The difference between antianxiety and hypnotic effects of these drugs often depends on dosage; low doses alleviate anxiety whereas higher doses induce sleep.

Benzodiazepine Receptor Agonists

• Similar action to Benzodiazepines.
• May develop tolerance and dependence over time.
• Common side effects include:
  • Sedation
  • Dizziness
  • Headaches

Dual Orexin Receptor Antagonist (DORA)

• Example: Lemborexant (Dayvigo).
  • Function: Blocks orexin receptors to diminish excessive wakefulness at night, contributing to improved REM sleep.

Miscellaneous Drugs for Insomnia

• Doxepin (Silenor): An antidepressant used for sleep, typically at low doses.
• Over-the-Counter Agents:
  • Diphenhydramine
  • Doxylamine

Narcolepsy

• Definition: A rare sleep disorder characterized by sudden sleep attacks that occur without warning.
• Duration of attacks: These episodes can range from a few seconds to 30 minutes.
• Etiology: Often the exact cause remains unclear, but triggers can include intense emotions such as laughter or extreme fear/anger.
• Treatment: Involves the use of stimulants such as:
  • Amphetamines
  • Methylphenidate

Pharmacotherapy for Narcolepsy

• Modafinil (Alertec): A non-amphetamine stimulant.
  • Mechanism of Action (MOA): Not fully understood; suggested to stimulate α1-adrenergic receptor sites.
  • Additionally prescribed to manage sleep apnea.

Modafinil: Adverse Effects

• Stimulation: Can cause increased alertness.
• Insomnia: Recommended to take the medication in the morning to avoid sleep disruption at night.
• Tolerance and Dependence: Potential for developing tolerance and dependence on the medication.