Common and Connected
Depression and insomnia are common and possess common symptoms. Some estimate that 30% of Americans will eventually experience clinical depression, and perhaps 40% of adults complain that many or most nights they don't get enough sleep, wake too often, or feel unrested on awakening.
So which is chicken and which egg? Or are they both?
Depression Causes Insomnia
One of the earliest symptoms for many depressives is insomnia. They can't fall asleep. They can't stay asleep.
There are times you can almost diagnose depression by looking at individual sleep studies, where the sleep architecture goes fantastically out of line:
1. Deep sleep, where we produce growth hormone, a stage critical for memory and decision making, may altogether disappear with depression.
2. Awakenings and arousals increase dramatically. Sleep becomes highly fragmented.
3. REM sleep is often broken up, and its very appearance changes. Rapid eye movements may appear both erratic and dense. The changes are so characteristic that Professor Jerry Vogel and others from the 1970's on tried to treat depression by waking folks every time they started REM sleep. Preliminary results were strongly favorable, but faded.
Depressives and Sleeping Pills
As people become depressed they often identify sleeplessness as their main problem. Insomnia is common and holds little stigma; depression is a "disease" that can cost you jobs, insurance, relationships and self-esteem.
People in depressive episodes often seek sleeping pills, sometimes with desperation.
Generally they will feel better - for a while. Unfortunately the quality of sleep tends to decline as long as the depression is not fully treated.
Frequently sleep medications stop working altogether. Behavioral and other regimes may also then fail.
Many times I have seen depressed people taking enormous doses of sleeping pills who tell me, correctly, that they hardly sleep at all. I tell them, sadly, that until their depression gets better they will probably not sleep well. Sleep can be the last thing to normalize in a depressive episode.
So it's strange to many, including sleep clinicians, that depression can also cause insomnia's opposite - prolonged sleepiness. It's even more of a surprise that forcing people to stay awake at night can improve depression.
Depression Also Causes Prolonged Sleepiness
When most people think of people who sleep too much they usually don't consider depression as the cause. Their first thoughts (and that of most physicians) is that sleep apnea, or leg kicks, narcolepsy or medications are to blame.
It turns out many who sleep too much are suffering from depression. In groups studied by Michel Billiard at the University of Montpellier, once common sleep disorders like sleep apnea were dealt with, depression was the major cause of hypersomnia.
How can an illness cause insomnia and its opposite? Try to think of depression as what it is - a massive deformation in the brain's information network. Some depressives sleep too much (though perhaps in part because their sleep quality is poor) while others sleep hardly at all. Just as there are hundreds of causes of depression, its manifestations are manifold. People with bipolar illness may demonstrate a more compressed version of such aberrant brain sleep control, sleeping two hours one night and sixteen hours the next.
Can Forced Insomnia Treat Depression?
Keep normal people up all night and many describe transient euphoria. Keep depressives up all night and many feel much better mood. Yet the effect disappears as soon as they fall asleep. Even a few short minutes of slumber and the more normal mood is gone.
Researchers are extremely interested in why this happens. Theories abound. Many have to do with the basic "uses" of sleep itself. Yet the nature of depression's effects on sleep is terribly complicated - one reason brief interludes of sleeplessness are rarely used to treat depression.
Insomnia Causes Depression?
It has been known for decades that chronic insomnia was associated with depression - but did it cause it? Jules Angst, professor of clinical psychiatry, observed the young citizens of his city, Zurich for decades. The longer they were insomniac the more depressed they became. When insomnia became chronic, lasting ten years or more, depression's incidence became frequent, affecting a third or more.
But was this merely a correlational finding? Would these people have gotten depressed anyway, and just showed up first with symptoms of insomnia?
More recent studies argue no. First, data with young people show that those who have trouble with insomnia tend to experience far more depressions. And data is arriving from varied sources that sleeplessness alone - for whatever reason, including shift work - is associated with higher rates of depression.
Insufficient sleep has many different effects. Higher rates of depression are among them.
So What's Chicken and What's Egg?
Insomnia and depression are dialectically related - both influence each other. If you are insomniac, the lack of rest required for your body's natural regeneration provokes a greater tendency to depression. Depression itself massively reorders sleep, often in the form of horribly disrupted sleep architecture and seemingly "untreatable" insomnia.
Both make the other worse. Can improving either decrease the chance for both? Many clinical studies would argue yes.
What You Can Do For Both Depression and Insomnia
Depression and insomnia are clinical syndromes. Their many different symptoms are highly interrelated, and engage many similar brain areas and functions. So it makes sense that some things you do to prevent or treat one may help the other. Treating either usually requires a mix of different therapies, ranging from cognitive-behavioral to physical to pharmacologic to techniques of rest-relaxation.
Fortunately there are simple things most people can do on their own that engage basic activities of life:
1. Physical activity - some people make their way out of depressive episodes through heavy bouts of aerobic exercise. Many studies argue physical activity is as effective as medications for relatively minor depressions.
Most folks sleep at least little better as they become fitter. Exercise in the morning helps some sleep better, particularly older women, while others find evening exercise, 3-5 hours prior to sleep, is more effective for them.
Physical activity helps more than sleep and depression, of course. Particularly when it is combined with
2. Sunlight - Morning light and physical activity improves mood and can also help people sleep. Light is a drug, changing mood, biological clocks, immunity and performance. Decreasing light exposure before sleep may also make falling asleep easier - and perhaps 95% of Americans use light-filled electronic media in the hour before they fall asleep.
3. Social support - mostly unheralded in the US, social support is a very important reason for improved lifespan. People who have more friends and colleagues have less depressive episodes. Social support can also aid sleep - especially when people close to you keep you on a regular sleep-wake cycle, as in
4. Keeping regular body clocks. Time rules life. Many insomniacs and depressives are aided by regular schedules of moving, eating, and sleeping. The simple rhythm of Food-Activity-Rest (going FAR) can help here.
Insomnia and Depression
The different symptoms we experience may feel and sound nearly unique to many of us, but not to brain scientists. Insomnia and depression are deeply interlinked, as are the brain areas involved in both - the information network is often similar. Both depression and insomnia can make the other worse. Fortunately simple life activities can be used to prevent both - and to treat them.