Bipolar disorder is more prevalent than was previously thought,
but this illness, particularly
bipolar disorder II, is still poorly recognized
in the family-practice setting. It is estimated that only one-third of affected
people are diagnosed. Of those, less than a third receive appropriate therapies.
This makes bipolar disorder the most undertreated of psychiatric conditions.
Conditions similar to bipolar disorder
When making a diagnosis of bipolar disorder, it is important
that the physician rule out other conditions that may be causing symptoms of
bipolar disorder symptoms.
Distinguishing Mania from Normal Euphoria or Joy. A major
difficulty with a diagnosis of bipolar disorder is the tendency for a patient to
be unable to recognize his or her own condition, particularly the manic form.
The patient often denies these symptoms, which they may perceive as positive
feelings. The physician should take a careful and complete history of any and
all episodes of depression, mania, or both.
Hypomania, the less severe variant
of mania, may be particularly difficult to distinguish from normal joy or
euphoria. It can often be differentiated by the following characteristics:
-
Hypomania persists for at least four days.
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Most patients with hypomania are easily distracted and overly
talkative.
-
Patients with hypomania tend to not function very well.
Distinguishing
Unipolar from Bipolar Depression. People
with bipolar disorder are more likely to first seek help because of a
depressive
episode. Indeed about 16% of people with bipolar disorder do not have a manic
episode until they have experienced three or more depressive episodes. In such
cases, the condition is often diagnosed as depression. An accurate diagnosis is
important because bipolar disorder patients who are inappropriately medicated
with antidepressants (antidepressants can initiative mania in bipolar patients)
have a higher incidence of rehospitalization than other bipolar disorder
patients do.
A family history of manic-depressive illness may make a
physician suspicious, but a diagnosis of bipolar disorder cannot be established
until a manic or hypomanic episode has occurred.
Bipolar disorder should be suspected in patients who have
previously been treated for depression and who had an initial fast and good
response, which was followed by failure. And, furthermore, they were then
resistant to other antidepressants. Bipolar patients are also more likely to
have atypical depression symptoms and to be emotionally volatile.
Attention Deficit Hyperactive Disorder (ADHD). Children
or adolescents with manic-depressive illness may be inappropriately diagnosed
with attention deficit hyperactivity disorder. ADHD and bipolar disorder often
cause inattention and distractibility, and the two disorders may be difficult to
distinguish, particularly in children. In some cases, ADHD in children or
adolescents can even be a marker for an emerging bipolar disorder. The primary
way to differentiate bipolar disorder from ADHD is by the presence of a manic or
hypomanic episode, which occurs in patients with bipolar disorder but not with
ADHD. Most children with bipolar will also respond to the drug valproate (Depakote),
which doesn't typically work for ADHD in children.
Schizophrenia. Severe manic episodes that include
delusions and hallucinations may be easily confused with schizophrenia.
(African-American men, for instance, are more likely to be diagnosed with
schizophrenia than with bipolar disorder.) The key factors that distinguish
bipolar disorder from schizophrenia are the following:
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The presence of one or more manic or hypomanic episodes can
often help distinguish bipolar disorder from schizophrenia.
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In schizophrenia, the emotional expression is flat, with no
variability in the voice, while people with bipolar disorder are typically
very expressive.
Substance Abuse. Up to 60% of bipolar disorder patients
abuse alcohol and drugs at some point in the course of their illness. Both
diagnosis and treatment are difficult in such cases, since substance abuse is
often a method of self-treatment, and withdrawal can produce symptoms of mania
or severe depression. The effects of cocaine in a heavy user can also produce
abnormal mood swings that closely resemble those of bipolar disorder.
Other Causes of Mood Swings
Other conditions that can cause mood swings include the following:
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Thyroid disorders. Hypothyroidism may be common in
bipolar patients, particularly women. (This condition can be identified with
a blood test).
-
Adrenal disorders (e.g., Addison's disease, Cushing's
syndrome).
-
Vitamin B12
deficiency.
Certain neurologic disorders (e.g., Huntington's
disease, epilepsy, brain tumors, encephalitis, multiple sclerosis).
A number of medications, including corticosteroids
and certain drugs used to treat anxiety, Parkinson's disease, and depression
can cause mood swings.
Laboratory Tests
The following tests may be helpful:
Imaging Tests
Noninvasive neuroimaging tests using magnetic resonance imaging
(MRI) and positron-emission tomographic (PET) scans are being used in clinical
trials for detecting abnormalities in the brain that might identify bipolar
disorder and for testing the effectiveness of treatments.