Non-24-Hour Sleep-Wake Disorder
What is Non-24-Hour Sleep-Wake Disorder?
Non-24-Hour Sleep-Wake Disorder (Non-24) is a circadian rhythm disorder that affects the timing of a person's internal body clock (or circadian rhythm), leading to disrupted sleep-wake cycles. Non-24 disrupts a person's ability to fall asleep and stay asleep at the same time every day, ultimately resulting in significant disruptions in their day-to-day life.
People with Non-24 often experience severe daytime fatigue, sleep-onset insomnia, decreased motivation and difficulty focusing. It can also negatively impact cognition, mood, relationships, work and physical health. Non-24 is especially common among people who are completely or partially blind, as the lack of exposure to light cues can cause the body to become out of sync with the 24-hour day-night cycle.
Symptoms of Non-24
Non-24 is a form of “free-running,” where the circadian rhythm gradually shifts over several days and is not synchronized with the environment. Symptoms typically occur in daily cycles that range from 24 to 48 hours, and include:
- Fatigue and lack of energy throughout the day
- Difficulty falling asleep and staying asleep
- Decreased alertness and concentration
- Extreme daytime sleepiness
- Confusion and disorientation
- Irritability and mood swings
- Reduced quality of life
Diagnosing Non-24
The diagnosis of Non-24 is largely based on a patient's self-reported sleep history and the patterns of their sleep cycles. A physician may also conduct physical exams to rule out any other underlying medical conditions. A sleep study may be recommended to measure a patient's sleep-wake patterns and observe any underlying sleep problems.
Treatment Options for Non-24
The mainstay of treatment for Non-24 is light therapy. This involves exposing the patient to a bright, artificial light in the morning and/or evening in order to reset their internal body clock. Experts also recommend that individuals with Non-24 take measures to promote better quality sleep, such as establishing a comfortable sleep environment, maintaining a consistent sleep schedule, and practicing relaxation techniques. In some cases, medications may also be prescribed to help with sleep disturbance or anxiety associated with the disorder.
