Circadian rhythm is often referred to as the human internal clock. Its cycle is approximately 24 hours long. This cycle interacts with the homeostatic sleep drive to produce one waking period during the day and continuous sleep during the night. When this cycle is broken, our sleep is fragmented and scattered across a 24-hour day, creating sleep problems.
Types of Circadian Rhythm Disorders
- Delayed Sleep Phase Disorder can occur in “night owls” when the preferred time for sleep is typically after 2 a.m. with wake up time after 10 in the morning. This results in difficulty falling asleep and waking up at times conducive to school and work. When the individual attempts to wake up earlier, they become sleep deprived and alertness may be impaired. This condition is most common in adolescents.
- Advanced Sleep Phase Disorder is more common in older adults who are sometimes referred to as “morning larks” – when the internal clock prefers early times for sleeping and waking. This makes it difficult to stay awake through the evening hours and people who have this kind of circadian rhythm sleep disorder often wake up much earlier than desired.
- Irregular Sleep Wake Disorder is most commonly seen in elderly patients with dementia and refers to a lack of rhythm in a person's sleep and wake cycle. Sleep occurs irregularly throughout a 24-hour period. The individual cannot sleep through the night and has difficulty maintaining wakefulness during the day.
- Free-running disorder or non-24 hour sleep-wake disorder is rare and seen more commonly in individuals with blindness. Bright morning light (sunrise) aligns our internal clock to the 24-hour day. When light perception is absent, the sleep period drifts later and later each day, causing this disorder.
- Jet Lag happens during air travel when we traverse time zones faster than our body clocks can adjust. This causes a mismatch between the preferred sleep and waking times and the destination sleep and waking times.
- Shift work sleep disorder is due to an unconventional work schedule that causes you to remain awake during preferred sleep times and, the available time for sleep occurs when your body prefers to be awake. As a shift worker you experience sleepiness while at work and insomnia during the time you have available to sleep. You may also experience difficulty concentrating, headaches, and low energy levels while awake.
Treatment Options
We are able to treat many circadian rhythm disorders effectively and offer treatments such as:
- Appropriately timed bright light exposure
- Melatonin
- Sleep scheduling and
- Other behavioral modifications
While melatonin is not yet FDA approved, we find that it may be beneficial for circadian rhythm sleep disorders under the supervision of our specialized sleep medicine physicians.
Next Steps
Please call 734-936-9068 to schedule a clinic visit.
We will need a referral from your physician before your appointment. We look forward to helping you resolve your sleep issues.