The body’s circadian clock controls the timing of biological rhythms like sleep patterns, hormone levels and natural fluctuations in body temperature. People with circadian rhythm sleep wake disorders have difficulty falling asleep or waking up at the right time, have trouble staying asleep, and may wake feeling unrefreshed. Symptoms of a circadian rhythm sleep wake disorder include the inability to fall asleep or stay asleep, daytime fatigue, and poor concentration.
What causes circadian rhythm sleep wake disorders?
Because light helps the body regulate its circadian rhythm, individuals with blindness and shift workers are more susceptible to circadian rhythm abnormalities. People with chronic insomnia are more likely than others to have a circadian rhythm sleep disorder. Hypersensitivity to melatonin and low light exposure during morning hours are also linked to an increased risk for these disorders.
A sleep medicine physician will take a detailed health history when diagnosing a circadian rhythm sleep disorder. Patients are usually asked to keep a sleep journal for a period of time to chart sleep patterns and aid clinicians in making a diagnosis.
Jet lag disorder, also known as jet lag, may be the most common circadian rhythm sleep wake disorder, but other less common disorders belong to this group of conditions.