Discrepancy of Sleep in Patients with Paradoxical Insomnia
It is believed that the discrepancy in those with SSM is due to elevated central nervous system activity, also called hyperarousal.
It can be difficult to help a patient who has insomnia. It can be even more frustrating when the patient swears that they have not slept in weeks, and you cannot convince them otherwise. You know they are sleeping or they would be experiencing more symptoms than they present with, but despite your best efforts, they are still complaining they cannot sleep. Sometimes a spouse might add that they look like they are sleeping, maybe even snoring, but the patient is adamant that sleep eludes them. The patient may be suffering with paradoxical insomnia.
In patients with paradoxical insomnia, also called sleep state misperception (SSM), there is a significant discrepancy between objective sleep quality and subjective perception of sleep. These patients are sincere in their complaints; this is not a case of malingering. However, when the patient has a sleep study, they are found to have a normal duration and quality of sleep.
The underlying reason for this type of insomnia is not well understood. It is believed that the discrepancy in those with SSM is due to elevated central nervous system activity, also called hyperarousal. Others theorize that pre-sleep anxiety and worry can give the patient the feeling of being awake when they are asleep. Another theory is that spontaneous sleep disruptions can cause patients to underestimate their sleep. The most recent findings indicate that patients with SSM have lower theta EEG activity and higher alpha, beta and gamma wave activity. The elevated alpha activity might be the mediating factor in the patient's feeling of being awake.
Also, in patients where subjective reports and objective data did not align, there appeared to have been CNS hyperarousal especially in the prefrontal cortex as well as superior frontal gyrus (SFG). The SFG is involved in higher levels of executive functioning, attention, and information processing. So, the brain is not shutting down the way it should.
As science continues to investigate the possible causes, those with paradoxical insomnia continue to feel miserable. Even though they perceive a lack of sleep, they generally function well during the day. Treatment includes reassurance and validation of concerns. CBT and/or sedative hypnotics may benefit some but are not always helpful. There is risk of dependence with sleep aids, so the risk/benefit aspect must be weighed carefully. Keep in mind that the objective sleep measures will not change with the medication, but it can help the subjective feelings of the patient.
When trying to formulate a plan to help this patient, keep in mind the way you felt the last time you didn't sleep well, and imagine how you would feel if that was your experience every night. These patients are very grateful when you try to help.
- Attarian, Hrayr, “Paradoxical Insomnia.” Clinical Handbook of Insomnia. Second edition. Humana Press.
- Fan-Chi Hsiao, et al. “The Neurophysiological basis of sleep discrepancy between objective and subjective sleep during the sleep onset period: an EEG-fMRI study. “Sleep. March 24, 2018.