Sleep Flashcards
How many stages of sleep is there?
4 stages in non-REM sleep
REM sleep - rapid eye movement (5-30mins)
Deepest sleep is at stage 4
Length of sleep cycle decreases as sleep goes on
Which neurotransmitter promotes REM sleep?
Melanin- concentrating hormone
This comes of the lateral hypothalamus
What is the role of orexin?
Orexin is produced from the lateral hypothalamus and promotes wakefulness. Orexin neurones also stimulate and reinforce locus coeruleus, raphe nuclei and the tuberomamillary nucleus which produces NA, 5-HT and H respectively that also promotes wakefulness
What drives sleep?
Ventrolateral preoptic area (VLPO) have neurones that inhibit neuronal activity of nuclei involved in arousal and wakefulness ie: LC, RN, RMN and orexin
Why do we transition into sleep?
Wakefulness is maintain by a positive feedback loop of the ARAS
BUT
1. overtime, homeostatic (accumulation of adenosine) and circadian drives build
2. Positive feedbacks fades, sleep promoting areas start to dominate
What is the role of melatonin?
Is a physiological signal for darkness
Facilitates onset of sleep and maintenance of sleep
Why do we need sleep?
- To restore normal balance to neuronal areas
- Neurodevelopment
- Memory consolidation
What are some types of dyssomnias and parasomnias?
Dyssomnia: Insomnia disorder, hypersomnolence disorder, narcolepsy
Parasomnia: Nightmare disorder, sleep terror, sleepwalking disorder
What are some extrinsic and intrinsic causes of dyssomnias?
Extrinsic: stress, hygiene
Intrinsic: restless leg syndrome, sleep apnoea
What are 4 types of primary insomnias?
- Acute transient insomnia (identifiable stressor)
- Psychophysiological insomnia (learned or conditioned insomnia, persistent even after stressor is removed)
- Idiopathic
- Paradoxical insomnia (sleep state misinterpretation)
What can secondary insomnia be due to?
- Inadequate sleep hygiene
- Psychiatric disorder
- Medical condition such as restless leg syndrome, pain, hotflushes
- Drugs or substance
What management options are there for insomnia?
Non pharmacological: mainstay
Pharmacological: short term, intermittent use of sedative/ hypnotics
What type of behavioural therapies are available?
- Stimulus
- Sleep restriction
- Sleep hygiene
- Relaxation training
- Cognitive therapy
When should hypnotics not be used?
- Sleep apnoea
2. Alcohol abuse (respiratory depression)
How long should BZD be used for to treat insomnia?
not more than 7-14 days of continuous use use intermittently (every 2nd to 3rd night)
How can pharmacist play a role in managing insomnia?
- Provide information
- Identify potential cause of insomnia
- Check duration
- Discourage inappropriate use of OTC medication
What is restless leg syndrome?
- The urge to move legs, usually accompanied by unpleasant sensation
- The urge begins and is worse during periods of rest or inactivity
- Partially relieved by moving such as walking or stretching
- worse during early evening or night
Pathophysiology behind restless leg syndrome?
Associated with dopaminergic dysfunction and abnormal brain iron metabolism
Non pharmacological treatments for restless leg syndrome?
- Improve sleep wake cycle
- Regular moderate cycle
- Relaxation therapy, thermal baths, massage
- Correcting iron deficiency
Pharmacological treatment for restless leg syndrome?
- Dopaminergic agonist: levodopa
- Dopaminergic agonist (non ergot derived): rotigotine, pramipexole
- Augmentations: gabapentin, clonazepam
What is sleep apnoea?
Results from loss of respiratory effort during sleep
presents:
- frequent night awakening
- depression
- insomnia
- sleep disruption
- snoring
May required nasal oxygen or CPAP
What is narcolepsy?
Irresistible urge to sleep
What treatment is available for narcolepsy?
- Schedule naps
- Central nervous system stimulants: methylphenidate or dexaphetamine, clomipramine, modafinil, TCA, SSRIs
- Modafinil usually started first
What pharmacological treatments for sleep disorders?
- BZD
- Z drugs
- Antihistamines
