Non-24: Impact on Health and Daily Living

While most people live according to a 24-hour social day and maintain a regular sleep-wake schedule, the Non-24 patient displays periodically recurring problems with sleep initiation, sleep maintenance, and waking, as the circadian cycle of wakefulness and sleep moves in and out of synchrony with the fixed social sleep episode.1

When circadian rhythms are out of phase with conventional sleep-wake patterns, as they may be in patients who are blind with Non-24, these patients may suffer a decrease in well-being such as2:

  • Impairment in sleep duration, timing, and quality3
  • Alterations in mood3
  • A reduction in daytime functioning and participation in social activities3
  • Potential impact on metabolic and cardiovascular homeostasis2

Read on to know what symptoms to look for in your patients who are totally blind.

Non-24: A Patient’s Perspective

Patients with Non-24 have been living with these highly disruptive symptoms for numerous years or all of their lives. For many, they have either learned to live with the issues or don’t make the connection that their issues are related to their lack of light perception.

“I suffer from being awake at night, and then just feeling wired; not being able to function totally up to par during the day because I have a lack of sleep.”

The symptoms of Non-24 are often confused with sleep disorders, such as insomnia. But unlike insomnia, Non-24 is a condition in which a patient’s circadian rhythm of sleep and wakefulness is out of phase with the 24-hour day-night cycle.4

And while symptoms of Non-24 differ from patient to patient, the common denominator for all patients is its impact on their well-being and its disruption of their daily living.2 Non-24 patients may experience:

  • Extreme sleepiness during the day3
  • Unintended napping during the day4
  • Poor quality of sleep at night3
  • Periods of not sleeping2
  • Sleeping through the night but not feeling refreshed the next day3
  • Dozing off during the day3
  • Problems with concentration/difficulty focusing5
  • Trouble taking part in daily activities5

Knowing that the consequences of Non-24 affect approximately 70% of people who are totally blind can help guide you in asking appropriate questions to make an informed diagnosis.6,7

If you have patients who are totally blind with sleep-wake complaints, consider a diagnosis of Non-24 (ICD9 Code 327.34/DSM5 Code 307.45).2-4,8

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References 1. Okawa M, Uchiyama M. Circadian rhythm sleep disorders: Characteristics and entrainment pathology in delayed sleep phase and non-24 sleep-wake syndrome. Sleep Med Rev. 2007:11:485-496. 2. Zisapel N. Circadian rhythm sleep disorders: pathophysiology and potential approaches to management. CNS Drugs. 2001;15(4):311-328. 3. Uchiyama M, Lockley SW. Non-24-hour sleep-wake syndrome in sighted and blind patients. Sleep Med Clin. 2009:4;195-211. 4. American Academy of Sleep Medicine. Non-24-hour sleep-wake syndrome. In: The International Classification of Sleep Disorders, 2nd ed.: Diagnostic and Coding Manual. Westchester, IL: American Academy of Sleep Medicine; 2005:117-137. 5. Lockley SW, Cohen D, Harper DG, Uchiyama M. Other circadian rhythm disorders: non-24-hour sleep-wake disorder and irregular sleep-wake disorder. In: Barkoukis T, Matheson JK, Ferber R, Doghramji K, eds. Therapy in Sleep Medicine. Amsterdam, The Netherlands: Elsevier; 2011:411-424 6. Sack RL, Lewy AJ. Circadian rhythm sleep disorders: lessons from the blind. Sleep Med Rev. 2001:5;189-206. 7. Dressman MA, Licamele L, Feeney J, Polymeropoulos MH. Seventy percent of totally blind people with sleep complaints are not entrained to the 24-hour clock. Poster presented at: 26th Annual Meeting of the Associated Professional Sleep Societies, LLC; June 10, 2012; Boston, MA. Poster 49. 8. American Psychiatric Association. Non-24-hour sleep wake syndrome. In: Diagnostic and Statistical Manual of Mental Disorders, 5th ed.: DSM-5; American Psychiatric Association; 2013:845.

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