Depression and Your Body -- It's Physical, Too

If you visit your primary care physician's office because of sore muscles, a disrupted sleep schedule, migraines or digestive issues, you might not expect a diagnosis of depression. But there's a chance you'll get one -- even if you're not necessarily aware of "feeling" sad.

Major depressive disorder is a condition that's characterized first and foremost by a persistent low mood and lack of interest in life. But many people don't know the disorder has a number of other symptoms, and they're not just psychological.

In fact, "most of the signs are physical," says Michael Gitlin, a professor of clinical psychiatry at the University of California--Los Angeles School of Medicine, and they range from changes in sleep, appetite and energy to widespread body pain, headaches and gastrointestinal problems. "They're so common that they're really inherently part of the definition of how we diagnose depression," he says.

But too often during the diagnostic process, psychological symptoms take a backseat to physical ones -- making patients and doctors alike unaware that the problem is depression in the first place. Screening individuals for not just physical -- but emotional -- symptoms, doctors say, is important for effective treatment.

Not One Symptom, Nor One Explanation

Doctors can't explain why, exactly, depression is tied to myriad physical maladies. But along with a low mood and loss of enjoyment in life, patients with depression often notice that something's "off." For example, points out Jordan Karp, an associate professor of psychiatry at the University of Pittsburgh School of Medicine, someone's lower back or abdomen might hurt. He or she might have a headache or experience constipation, diarrhea and other irritable bowel-type symptoms. Or that person will have numbness or tingling in their limbs. He or she will try to discover the source of the discomfort by looking for a physical cause, such as a thyroid issue or low blood count. This person doesn't realize, however, that the organ of interest is actually their brain.

While there's no one scientific explanation for this range of physical symptoms, Karp says, "we know depression lowers the pain threshold. There's both a shared psychology as well as a shared biology in the brain. Regions that modulate or regulate mood also regulate pain. If they are out of whack because of depression, people may be more likely to experience sensations as painful, or pain as more intense." He also points out that depression causes changes in the autonomic system, which might lead to gastrointestinal problems.

Still, Gitlin says, not all physical symptoms of depression -- tiredness, a lack of concentration or bowel issues -- have a definite medical explanation. "The exact biology of why people with depression have pain that feels worse, why they get constipated, why they have low energy -- one day we'll know the answer to that, but today is not that day," he says.

An Incomplete Evaluation

When patients experience depression's physical side effects, doctors say, their first instinct is to head to their primary care physician's office to pinpoint what's wrong. Once there, they'll answer a series of screening questions and might undergo lab tests. They're searching for an easily identifiable physical answer. Often, they won't consider mentioning they feel depressed, and the busy doctor -- whose focus isn't mental health -- won't suggest an evaluation.

"It is very normal for [doctors] to screen patients for diabetes, and to screen you for hypertension and blood pressure. It's not very common to screen patients for depression," says Madhukar Trivedi, a psychiatrist at the University of Texas Southwestern Medical Center in Dallas. "So unless you ask patients to provide the nine or 10 symptoms that make up the diagnosis for clinical depression, often patients forget to tell the primary care physician [about non-physical symptoms]."

Even if physicians do ask patients if they're depressed, they don't always receive a clear answer -- and for a variety of reasons, Trivedi and Karp say. Sometimes an individual will focus on his or her bloated belly and fail to mention an accompanying bad mood because he or she fears the stigma of mental illness. Other times, patients aren't educated about the traits of depression and have no idea what they're experiencing. And occasionally they think it's "normal" to feel sad, so they don't mention that their frequent migraines also come with a side of the blues. Plus, there's always the chance they simply lack the vocabulary to explain what's wrong.

"Some patients are just not as psychologically minded, and maybe have some difficulty with [turning] the emotions they're experiencing into words," Karp says. "So they might feel crappy, but it's easier to say that their back hurts, they feel tired and worn out and that they're grumpy."

These various factors, physicians say, make an already difficult-to-diagnose condition harder for both patients and doctors to identify. And they're likely common among patients, as indicated by a noted World Health Organization survey conducted in the early 1990s. Researchers analyzed data from more than 25,000 people living in 14 countries who had recently visited their primary care physicians, and found that 69 percent of those who met the diagnostic criteria for depression only told their doctors about their physical symptoms. And 11 percent denied experiencing psychological symptoms when the doctor asked about them.

Recognizing -- and Treating -- Depression

So does a recurring headache coupled with a feeling of malaise mean you're clinically depressed? Doctors say it isn't always so clear-cut. Depression is a complex disease, and it presents in different ways and combinations. There's no "normal" way that a patient experiences it, nor will it look the same in everyone else.

However, Trivedi says, there's a difference between an isolated pain in the arm -- which is likely to be musculoskeletal -- and a variety of combined physical symptoms that are typically found in patients with depression.

Therefore, he says, primary care physicians should keep an eye out for whether patients have problems such as pain, irritable bowel syndrome and poor sleep habits -- and then screen them for emotional symptoms just to be safe.

If the physical symptoms do turn out to be a part of the clinical depression, Trivedi says, the patient will most likely be treated with therapy, exercise and medication. And as the emotional symptoms improve, he says, so will the physical ones. However, he cautions, the symptoms should be measured on an ongoing basis. If they don't disappear, another treatment might be necessary.

To be safe, Gitlin says, doctors should also perform a series of screening lab tests or exams. The patient might not be depressed, and instead have a separate condition or an independent pain disorder. Or if depression does end up being present, co-morbidity -- the simultaneous existence of two chronic diseases or conditions in a patient -- is common, particularly among people with mental illness. There's a chance the pain might be compounded by the depression, but not necessarily caused by it.

But perhaps most important, he says, is educating patients about depression -- in all of its physical and emotional forms. "Simply having people who don't feel good in some vague and generic way to think, 'Gee, maybe this is part of a psychiatric problem,' is a big deal in and of itself," he says. "We've already moved forward if we're there."