Sleep case #1

Case

• 64 yo male smoker with hyperlipidemia• BMI 28• Prev diagnosis of OSA• Referred for daytime sleepiness

Prev results

• 12/2006 sleep study: AHI 15.8• 5/2007 PAP titration – good response to CPAP

6cm, 54 mins of sleep including REM-supine seen

• Did not get home CPAP at that time• Summer 2012: Another provider started him

on CPAP based on 2006/2007 study results and ordered PSG which was performed in 10/2012

Visit Jan 2013• Started on CPAP over the summer 2012• Using it nightly and has met compliance with 4.5h

ave use• Feels he is sleeping better• No improvement in daytime sleepiness (ESS 18/24)• Irregular schedule• Difficulty falling and staying asleep• Estimates he gets 3-6 hours sleep/night• Works as a school bus driver

Assessment? Next steps?

Any special considerations in this patient?

10/2012 sleep study

Sleep study results 10/2012• TIB 424 min TST 344 min WASO 67 min • Sleep efficiency 81%• Sleep latency 11 mins, REM latency 17.5 mins• Sleep stages: 4.1% N1, 70.5% N2, 0% N3, 25.4%

REM• Position: 65 min supine, 278 min on left• AHI 5.2 overall, supine 10.9, REM 16.5, supine REM

57• Sat >90% entire study

Impression?Next steps?

PSG on CPAP/MSLT performed

PSG/MSLT results• PSG: TST 382 mins, efficiency 83%, CPAP

titrated from 6cm to 8cm. AHI 0.• MSLT– Nap 1: SL 1 min, REM latency 11 min– Nap 2: SL 1 min, no REM periods– Nap 3, SL 1 min, no REM periods– Nap 4: SL 4 min, no REM periods– Nap 5: SL 1 min, REM latency 5 min

• Mean SL: 1.8 min, 2 SOREMs

Diagnosis? Treatment?

Narcolepsy• #2 cause of daytime sleepiness (#1 = OSA)• Onset typically teens and early 20’s, but can be after

age 40• NL with and without cataplexy• Pathology of NL + cataplexy (~70%): loss of neurons

that produce orexin (a.k.a. hypocretin) – Wake-promoting– Stabilize wake/sleep– Inhibit REM

• NL without cataplexy less well-understood– Possibly less extensive loss of orexin

Symptoms of narcolepsy

• EDS• Fragmented sleep• REM-related phenomena intrude into

wakefulness– (Cataplexy)– Hypnagogic hallucinations– Sleep paralysis

Multiple Sleep Latency Test

• PSG the night before• 5 opportunities to nap, every 2 hours– 20 minutes to fall asleep– If fall asleep, allow 15 minutes of sleep

• Data obtained:– Number of naps in which sleep is obtained– Mean sleep latency • If no sleep, 20 minutes for that nap

– Number of SOREMs

Diagnosis of Narcolepsy

• EDS + cataplexy• Narcolepsy without cataplexy – definitive

diagnosis– Mean SL < 8 mins– ≥ 2 SOREMs

Treatment of Narcolepsy• Wake-promoting agents– Modafinil/armodafinil (provigil/nuvigil)

• Likely increase dopa signaling

– Amphetamines• e.g Methylphenidate

• REM-suppressing drugs– Increase norepi and serotonin

• Venlafaxine• Fluoxetine• Tricyclics

– Sodium oxybate at bedtime (analog of GHB, GABA analog)