Sleep problems are among the most common chronic problems in adults affecting an estimated 30-40% of the US adult population. Almost one-half of all persons with a sleep problem have insomnia which is difficulty getting to sleep or waking up during sleep and having trouble getting back to sleep. The coupling of sleep dysfunction with some degree of daytime fatigue is common.
These problems are related to disruptions in the neuroendocrine systems that have to do with controlling circadian rhythm. The rhythm is the timing of cycling of hormones and other factors that control the level of alertness at different times during the 24-hour cycle. Most noted of these hormones is cortisol.
Cortisol is a multi-tasking hormone being involved in energy and blood sugar regulation, alertness in the brain, inflammatory control and the timing of tissue regeneration. Looking at a 16-hour saliva cortisol profile, the levels are markedly different at different times of day.
Cortisol begins to rise in the 30 minutes before waking peaking in the first hour of the awake state. Most adults wake up about the same time every day the result of the cortisol awakening response. This response is caused by cortisol’s triggering of brain activation resulting in alertness. After the first hour cortisol drops moderately and maintains that level throughout the day.
Approximately 30 minutes before an individual’s typical sleep onset times, cortisol should lower substantially diminishing brain alertness and increasing sleepiness. This is accompanied by a drop in body temperature and yawning. A normal 16-hour saliva test is shown below. The green zone is the normal range, while the graphed line is the individual’s values.
Sleep onset insomnia is difficulty getting to sleep in the beginning of the night. This is most often related to high cortisol during that time inducing too much brain alertness. This pattern is shown below. The dotted lines represent the normal range for cortisol, while the solid line represents the individual’s values.
Several factors will cause elevated cortisol including excessive demand on blood sugar regulation, mental stress, chronic inflammation and chronic food or chemical sensitivity reactions. Low blood sugar is damaging to the brain. Humans have intense hormonal regulation of low blood sugar just as they do high blood sugar by insulin. When blood sugar begins to get too low, cortisol is released to trigger the liver to convert proteins into sugar. A byproduct of this cortisol reaction is increased brain alertness. With time the adrenal gland cortisol production becomes sustained maintaining ongoing cortisol elevation.
Other signs of high cortisol besides sleep onset insomnia may include bone and muscle loss. Cortisol “steals” the proteins used by the liver for sugar production from bone and muscle. If this is a chronic reaction to ongoing high cortisol, a “catabolic” state exists of bone and muscle loss.
With time over-worked adrenal glands will begin to fatigue resulting in too little cortisol availability. As this occurs periods of daytime fatigue begin to predominate and sleep onset insomnia will often switch to sleep maintenance insomnia which is waking up and having trouble getting back to sleep.
The last evening meal is fully metabolized in 3-5 hours. At that point blood sugar begins to fall triggering adrenal activation to activate sugar production by the liver. If the adrenals are normally functioning, they release a very small amount of cortisol to bump blood sugar back up. If cortisol output is too low, a second adrenal hormone, epinephrine or adrenaline, will increase to rebalance sugar causing sharp alertness and sleep disruption.
The test below shows adrenal fatigue that is associated with sleep maintenance insomnia.
Once the pattern and the causes of cortisol disruption is established specific correction protocol can be introduced. That may involve correction of food sensitivities, dietary improvement for better blood sugar control and other factors. Specific adrenal rehabilitation with nutrients and herbs will help rebalance adrenal hormone levels normalizing sleep patterns over time.
In some chronic patients the brain’s control of this circadian timing is disrupted. Neurofeedback or EEG guided brain training can be used to “reset” the brain’s control pattern. Indicators that this may be a factor in a sleep problem may include the co-existence of anxiety, depression, memory difficulty or other disrupted brain function.