Specific Bipolar Disorders
The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychiatric Association, 2013) categorizes bipolar disorders into three types:
- bipolar I disorder: features at least one manic episode.
- bipolar II disorder: features hypomania and depression. This is possibly the most common bipolar presentation in primary care. People with this type often use health services when they are depressed and often fail to respond sufficiently to conventional antidepressants (a situation that masquerades as treatment-resistant depression).
- cyclothymic disorder: features continuous biphasic mood instability for two or more years, but never severe enough to meet criteria for a major depressive episode, mania or hypomania.
Mixed Features in Bipolar Disorders
A common clinical scenario in primary care is a manic/hypomanic presentation in a patient on antidepressant monotherapy who has no prior de novo manic or mixed features. Mixed features is defined as a minimum of three pre-specified depressive symptoms while experiencing hypomania or mania, or three hypomanic symptoms while experiencing a major depressive episode.
If a patient manifests mixed or manic features while taking an antidepressant for depression or immediately upon discontinuing it, a diagnosis of bipolar disorder is made (this was a significant change made in the DSM-5). In previous versions of the DSM, mixed or manic/hypomanic episodes while taking an antidepressant did not count toward the diagnosis of bipolar disorder. Note that experiencing a hypomanic episode after starting an antidepressant does not indicate a bipolar diagnosis unless the hypomanic state outlasts the physiological effects of the drug. Rather, this reaction would simply be considered a drug side-effect. Manic responses, on the other hand, do not follow this pattern.
Some non-psychiatric conditions can present with symptoms of mania. Organic pathology can be reasonably excluded by focusing on biological factors that may be associated with mania. For example, a physical exam probing for neurological signs or evidence of head trauma may be warrant- ed. In addition, laboratory screening for thyroid abnormalities is generally recommended.
Other psychiatric disorders and considerations
Bipolar disorders share symptoms with other psychiatric disorders, including:
- major depressive episode with prominent agitation/anxiety
- premenstrual dysphoric disorder
- seasonal affective disorder.
Other psychiatric disorders and problems are described in the following sections.
Borderline personality disorder is not a diagnosis of exclusion for bipolar disorder. Many patients have both conditions. The central and defining features of borderline personality disorder are an enduring and pervasive pattern of interpersonal relations that is chaotic and tempestuous, with subjective complaints of emptiness and attachment difficulties. People with borderline personality disorder often have distal trauma (e.g., childhood adversity).
Approximately 50 to 95 percent of people with bipolar disorder experience psychosis. Psychotic features usually appear during manic rather than depressive episodes. Mood-congruent delusions (e.g., grandiosity) and mood-incongruent delusions (e.g., paranoia) are the most common psychotic features. Psychosis often presents as a form of thought disorder (e.g., tangentiality). Although hallucinations and vivid perceptions are also common, the presence of hallucinations underscores the need to rule out organic causes as well as substance use.
In any patient with psychotic features—even those who show common signs of bipolar disorder, such as grandiosity and other mood-congruent features—it is important to consider the possibility of a primary psychotic disorder such as schizophrenia.
Consider toxicology screening (with the patient’s consent) if you suspect illicit drug use.