July 2023 Sleep Case of the Month: Fighting for a Good Night’s Sleep

Meneena Bright MD

Sleep Medicine

Brigham and Women’s Hospital

Harvard Medical School

Boston, MA USA

A 31-year-old man presented for follow-up in the Sleep Medicine clinic. He has a past medical history of a seizure disorder and supraventricular tachycardia (SVT) and was referred after complaining of excessive daytime sleepiness. Current medications include citalopram and diltiazem. Four months prior, he was diagnosed with severe obstructive sleep apnea characterized by an apnea-hypopnea index (AHI) of 34 and an oxygen saturation nadir of 86%. The patient was initiated on continuous positive airway pressure (CPAP) therapy; however, he reported ongoing mask discomfort and difficulty with exhalation while wearing CPAP. Despite partial improvement in sleep fragmentation and daytime sleepiness, the patient reported sleeping for only 4 hours per night. The patient's sleep schedule was irregular, with bedtime ranging between 9:30 pm and 12 am, waking up at 5 am, and taking a daily nap for 4-5 hours in the morning during which he continued to use CPAP. Additionally, he described experiencing episodes of waking up from dreams, often screaming or throwing punches. A score of 15 on the Epworth Sleepiness Scale (ESS) indicated significant daytime sleepiness.

What should be done next? (Click on the correct answer to be directed to the second of five pages)

1. Begin oxygen at night
2. Begin self-titrating CPAP
3. Discontinue diltiazem
4. Neurology referral
5. Overnight laboratory polysomnography

Cite as: Bright M. July 2023 Sleep Case of the Month: Fighting for a Good Night’s Sleep. Southwest J Pulm Crit Care Sleep. 2023;27(1):1-3. doi: https://doi.org/10.13175/swjpccs027-23 PDF 

Alpha Intrusion on Overnight Polysomnogram

Ryan Nahapetian, MD, MPH^a and John Roehrs, MD^b

^aPulmonary, Allergy, Critical Care, & Sleep Medicine, University of Arizona, Tucson, AZ

^bSouthern Arizona Veterans Administration Health Care System, Tucson, AZ

Figure 1. Thirty second polysomnogram epoch showing stage N2 non-REM sleep with frequent bursts of alpha frequency waves (black arrows).

Figure 2. Thirty second polysomnogram epoch showing stage N3 delta sleep (black arrows) with overriding alpha frequency (red arrows)

A 30 year-old Army veteran with a past medical history significant for chronic lumbar back pain stemming from a fall-from-height injury sustained in 2006 was referred to the sleep laboratory for evaluation of chronic fatigue and excessive daytime hypersomnolence. His Epworth sleepiness scale score was 16. He denied a history of snoring and witnessed apnea. Body Mass Index (BMI) was 25.7 kg/m². His main sleep related complaints were frequent nocturnal arousals, poor sleep quality, un-refreshing sleep, prolonged latency to sleep onset, and nightmares. An In-lab attended diagnostic polysomnogram was performed. Sleep efficiency was reduced  (73%) and overall arousal index was not significantly elevated (3.2 events/hour). The sleep study showed rapid eye movement (REM) related sleep disordered breathing that did not meet diagnostic criteria for sleep apnea. There was no evidence for period limb movement disorder. However, the study was significant for alpha wave intrusion in stage N2 non-REM and stage N3 delta sleep. Example epochs are shown in figures 1 and 2.

Alpha wave activity is characteristic of drowsy wakefulness and represents the background electro-encephalographic (EEG) pattern of the occipital region of the brain. Alpha activity occurs when individuals close their eyes and the occipital region loses visual stimulus. Alpha-Delta sleep is defined by a mixture of 5-20% delta waves combined with alpha-like rhythms that are interspersed among the delta waves and was first described in 1973 by Hauri & Hawkins (1). Alpha-Delta sleep has been associated with various neuro-psychiatric conditions including schizophrenia, depression, schizoaffective disorder, narcotic addiction, temporal epilepsy, fibromyalgia, chronic fatigue syndrome, and chronic pain syndrome (1,2). Alpha wave intrusion has also been shown to occur in stage N2 non-REM sleep in individuals with fibromyalgia and chronic pain. Poor sleep quality is often reported in individuals with complaints of chronic pain. It is suggested that alpha wave intrusion correlates with pain severity and can be used as a monitor to assess response to therapy (3).

References

1. Hauri P, Hawkins D. Alpha-delta sleep. Electroencephalogr and Clin Neurophysiol. 1973; 34(3): 233-7. [CrossRef] [PubMed]
2. Manu P, Lane TJ, Matthews DA, Castriotta RJ, Watson RK, Abeles M. Alpha-delta sleep in patients with a chief complaint of chronic fatigue. South Med J. 1994; 87(4): 465-70. [CrossRef] [PubMed]
3. Roizenblatt S, Molodofsky H, Benedito-Silva AA, Tufik S. Alpha sleep characteristics in fibromyalgia. Arthritis Rheum. 2001; 44(1): 222-30. [CrossRef] [PubMed]

Reference as: Nahapetian R, Roehrs JD. Alpha intrusion on ovenight polysomnogram. Southwest J Pulm Crit Care. 2014;8(6):334-5. doi: http://dx.doi.org/10.13175/swjpcc075-14 PDF