By Hara Estroff Marano, published on October 22, 2004 - last reviewed on February 22, 2007
Are we a nation in pain? Some 45 million Americans are plagued by headaches. Up to 80% of us will have back pain during our lifetime. Over $4 billion is spent each year on pain medication—and that's just over the counter.
But chronic pain is more than just a physical burden. It is also a leading risk factor for depression. The two conditions are locked together in a complicated pattern that has a cyclical chicken-or-egg quality. No one yet knows whether pain causes depression or vice versa, or if the two aid and abet each other.
In one study, nearly 60% of depressed patients said they suffered from regular head, neck, abdominal or back pain. Many also suffered from dizziness and shortness of breath. On the flip side, almost a third of patients treated for pain also had depressive episodes. For a substantial number of people, possibly up to half of depression sufferers, bodily pain is the way depression presents itself.
Too often, however, neither sufferer nor doctor is aware of the true source of the problem and the depression goes untreated as well as unrecognized. It's not that the pain is "all in the head." No, the pain is indeed real, but it likely drives many people to primary care physicians or orthopedists in the mistaken belief that that something has gone awry in their body. And there follows an unproductive search for an organic source.
Physical symptoms are as important in treating the condition as in recognizing it. Failure to eliminate the pain symptoms reduces the chances of full recovery from depression. Persistent pain typically keeps depressed people from regaining full function in the personal and professional lives, and it raises the danger of suicide.
Like the emotional symptoms, the painful physical symptoms of depression arise in specific nerve pathways, ones presided over by the chemical messengers serotonin and norepinephrine. From their base in the brainstem, such pathways travel up into the highest reaches of the brain, the frontal cortex, where they help regulate thinking and mood. They also travel to parts of the brain that regulate eating, sleeping, and sex drive.
But serotonin and norepinephrine pathways also travel down into the spinal cord serving the rest of the body. And therein lies the problem.
Normally, as the body goes about its tasks, there are constant sensations generated by such routine operations as digestion and movement. Those sensations are generally suppressed from consciousness and ignored. That's what allows you to pay attention to the world outside your body.
That suppression is normally accomplished by serotonin and norepineprhine-rich nerves in the spinal cord. But they malfunction in depression and fail to operate efficiently.
As a result, routine sensations escape up into the brain, where they are interpreted as uncomfortable or even painful physical symptoms. With the body's natural pain-suppression mechanisms not working, routine feelings of discomfort are magnified into pain—when in fact nothing at all may be wrong.
Even though the medical community is recognizing that pain and depression go hand in hand, many doctors fail to see the connection. It's wise to think of unexplained pain as a marker for depression.