"Bipolarity" in the Setting of Dementia: Bipolar Type VI?

Clinical Delineation of Type VI

In the case of prototype VI being proposed here, mood disorder may only be evident from the sixth to seventh decade of life and onward --its presentation starting with mood instability that slowly progresses to attention and concentration problems (or increased distractibility), irritability, agitation, and irregular drive and sleep. Temperament is described as "strong," which may have been extremely useful for an extremely active life earlier, often with a charismatic style, but more manifest in strong sexual indiscretions in recent months. Complaints about memory or behavior at such an age prompt patients and/or relatives to pursue medical evaluation. After other medical conditions are excluded, depression producing "pseudodementia" is usually considered as the likely diagnosis. A therapeutic trial with an antidepressant is conducted if pseudodementia is considered the likely culprit. Such a treatment trial may yield increased irritability and anxiety, or brief improvement followed by increased mood instability, which frequently prompts dose increments or change of antidepressant, similarly to what often occurs with other softer bipolar patients.^[1] Lack of consistent improvement then typically leads to the diagnosis of dementia, and acetylcholinesterase inhibitors may be started. In our experience, frank manic switch is uncommon in this subtype -- perhaps because of its presentation as mood instability or because neurotransmitter systems such as the dopaminergic system have undergone considerable age-related decline.^[3] Nonetheless, in our experience, in addition to Alzheimer's disease (AD) drugs, these patients often need low doses of mood stabilizers and/or low doses of atypical antipsychotics.

Medscape Family Medicine. 2005;7(1) © 2005  Medscape

Cite this: "Bipolarity" in the Setting of Dementia: Bipolar Type VI? - Medscape - Jan 06, 2005.