Circadian rhythm disorders for clinicians

Circadian rhythm sleep-wake disorders are common. People have persistent or recurrent patterns of sleep disturbance due to alterations of the circadian timing of sleep.

Disorders include delayed phase sleep syndrome, which is common in teenagers, where sleep is delayed until very late at night. Other disorders include advanced sleep-wake rhythms, irregular and non-24 rhythms. Jet lag or shift work patterns occur when external factors cause the person’s rhythm to become out of phase with the environmental demands.

These conditions can be managed with behaviour changes and such treatments as bright light therapy and melatonin, so clinical assessment is crucial.

This information has been developed by SA Health and The University of Adelaide