Circadian Rhythm Sleep Disorder – Symptoms and Diagnosis
The trouble here does not arise from any inherent problem in your ability to sleep, but is caused instead by a mismatch between your innate sleep-wake cycle and the demands dictated by your environment. There are four different scenarios.
The first is the “night owl.” Your internal circadian rhythm is delayed and has you waking and sleeping several hours behind the rest of your world. Left to your own devices, you fall asleep well past midnight and wake up around noon or even later. You have no problem with this sleep pattern unless you are forced to conform to a “normal” nine to five work schedule. You find it impossible to fall asleep and wake up when everyone else does, gradually become sleep-deprived, have excessive daytime sleepiness, require several alarm clocks to get up, and feel miserable all morning.
The advanced sleep phase pattern, a.k.a. “early birds” or “starlings,” describes people with the opposite problem. You fall asleep shortly after dinner and wake up raring to go hours before sunrise. This usually results in less work or school impairment than being a night owl (and may even increase productivity), but starlings can miss out on a lot of nighttime recreation and put quite a damper on family fun.
The third kind of Circadian Rhythm Sleep Disorder is caused by frequent jet lag resulting from repeated travel to and from radically different time zones. There is a strong correlation between the severity of the impairment and the number of zones you traverse. The greatest difficulty results when you travel through more than eight different time zones in less than twenty-four hours. Most people are able to adapt more easily to westward travel and have a really tough time coming east. Starlings do better, however, adjusting to the advancing hours of eastward flight.
The fourth type of Circadian Rhythm Sleep Disorder results from the unsettling schedule demands of shift work. Nearly a quarter of Americans are employed in jobs that are off the typical 8 A.M. to 5 P.M. schedule. Working the night shift, or constantly rotating shifts, results in inadequate hours of sleep, poor sleep continuity, and the disruption of circadian rhythms. People who work rotating shifts tend to suffer the most impairment because they must constantly readjust their sleep-wake cycles. Even those with regular runs of overnight shift work (for example, four overnight shifts followed by three days off) have trouble because of the desire to keep going back to a “normal” schedule on the days off in order to be in sync with family members and store-opening hours. Insomnia is also common because of ambient daytime disturbances (traffic noises, sunlight, ringing telephones, and family and social obligations). Job performance and morale can be jeopardized by on-the-job fatigue resulting from the inability to sleep during off-hours.
According to the diagnostic manual, you have Circadian Rhythm Sleep Disorder if :
- – You have a problem falling asleep or excessive sleepiness during the day caused by a mismatch between your body’s internal clock and the sleep-wake requirements of your external world.
- – The mismatch comes from your being a night owl or an early bird, or having to do shift work, or constantly flying across time zones so that your body can never adjust to the time changes.
- – Your sleep problems are severe enough to interfere with your ability to function on a daily basis.
