Category: Depression-What you need to know
Tests Used to Diagnose Depression
If you are planning to see your doctor about
depression, here is information about the kinds of tests your doctor might
ask for. First, keep in mind that not every test is a "depression
test." Some tests aren't used to diagnose clinical depression but rather to
rule out other serious medical conditions that may cause similar symptoms.
In most cases, the doctor will do a physical exam and ask for specific lab
tests to make sure your depression
symptoms aren't related to a condition such as
thyroid disease or cancer. If your symptoms are related to another serious
illness, treating that illness may also help ease the depression.
Diagnosing Depression and the Physical Exam
Again, the goal with a physical exam is usually to rule out a physical cause
for depression. When performing the physical exam, the doctor may focus
primarily on the nervous and hormonal systems. The doctor will try to identify
any major health concerns that may be contributing to symptoms of clinical
depression. For example, hypothyroidism -- caused by an underactive thyroid
gland -- is the most common medical condition associated with depressive
symptoms. Other hormone disorders associated with depression include
hyperthyroidism -- caused by an overactive thyroid -- and Cushing's disease --
a disorder of the adrenal gland.
Many central nervous system illnesses and injuries can also lead to
depression. For example, depression might be associated with any of the
- central nervous system tumors
- head trauma
- multiple sclerosis
- various cancers (pancreas, prostate, breast)
Corticosteroid medications such as prednisone, which people take for
diseases such as rheumatoid arthritis or asthma, are also associated with
depression. Other drugs, including illegal steroids and amphetamines and
over-the-counter appetite suppressants, may
cause depression on withdrawal.
Diagnosing Depression and Lab Tests
Your doctor can usually tell if you have depression by asking you specific
questions and doing a physical exam. Your doctor may, however, ask for lab
tests to rule out other diagnoses. Your doctor will likely do blood tests to
check for medical conditions that may cause depressive symptoms. He or she will
use the blood tests to check for such things as anemia, and thyroid, hormone,
and calcium levels.
Diagnosing Depression and Other Testing Methods
The doctor may include other standard tests as part of the initial physical
exam. Among them may be blood tests to check electrolytes, liver function, and
kidney function. Because the kidneys and liver are responsible for the
elimination of depression medications, impairment to either of these two organs
may cause the drugs to accumulate in the body.
Other tests may include:
- CT scan or MRI of the brain to rule out serious illnesses such as a brain
- electrocardiogram (ECG), which is used to diagnose some heart problems
- electroencephalogram (EEG), which uses an apparatus for recording
electrical activity of the brain
Depression Screening Tests
After discussing your mood and the way it affects your life, your doctor may
also ask you questions that are used specifically to screen for depression.
It's important to keep in mind that the inventories and questionnaires the
doctor may use are just one part of the medical process of diagnosing
depression. These tests, however, can sometimes give your doctor better insight
into your mood. He or she can use them to make a diagnosis with more
One example of a screening test is a two-part questionnaire that has been
shown to be highly reliable in identifying the likelihood of depression. When
you take this test, you will be asked to answer two questions:
- During the past month, have you been bothered by feeling down, depressed,
- During the past month, have you been bothered by little interest or
pleasure in doing things?
Your answer to the two questions will determine what the doctor does next.
The doctor may ask you additional questions to help confirm a diagnosis of
depression. Or if your answers indicate you do not have depression, the doctor
may review your symptoms again to continue the effort to find the cause.
Studies show that these two questions, especially when used with another test
as part of the assessment process, are highly effective tools for detecting
most cases of depression.
Your doctor may use other depression screening instruments as well. Examples
- Beck Depression Inventory (BDI), -- a 21-question multiple-choice
self-report that measures the severity of depression symptoms and feelings
- Zung Self-Rating Depression Scale -- a short survey that measures the level
of depression, ranging from normal to severely depressed
- Center for Epidemiologic Studies-Depression Scale (CES-D) -- an instrument
that allows patients to evaluate their feelings, behavior, and outlook from the
- Hamilton Rating Scale for Depression (HRSD), also known as the Hamilton
Depression Rating Scale (HDRS) or abbreviated to HAM-D -- a multiple
choice questionnaire that doctors may use to rate the severity of a patient's
When you take a test or inventory, you may feel uncomfortable responding
honestly to questions or statements that are made. The person who administers
the test will be asking about depression and mood, depression and cognition,
and the physical feelings of depression such as lack of energy, sleep
disturbance, and sexual problems. Try to be as honest as you can when assessing
your symptoms. Then your doctor can make an accurate diagnosis and prescribe
the most effective treatment.
If the Diagnosis Is Depression
Depression is highly treatable. Consequently, a depression diagnosis can
start you on the road to a healthier life without feelings of helplessness,
hopelessness, and worthlessness.
Once your doctor makes a depression diagnosis, you need to follow the
treatment program to get better. It's important to take the medications as
prescribed. You also need to follow through on making lifestyle changes and
working with a psychotherapist if that's what your doctor recommends. Millions
of people with depression suffer needlessly because they don't get professional
help that starts with a doctor's diagnosis.
Amal Chakraburtty, MD on March 08, 2010
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