Manic depressive illness is a biological brain disorder that produces significant alterations of mood and psychosis. Mania in the elderly occurs in three forms: (1) Bipolar patients who get older (2) elderly patients with pre-existing depression who develop manic symptoms and (3) elderly patients who first present with mania. Late life onset mania is relatively uncommon and may signal underlying neurological diseases, e.g., stroke, brain tumor etc. Approximately 5% of elderly psychiatry units are manic. Among elderly patients with mania (table 1), 26% have no past history of mood disorder, 30% have pre-existing depression, 13% have past mania and 24% have organic brain disease. Although the life expectancy of bipolar affective disorders is probably shorter than that of the general population due to suicide and alcoholism, many bipolar patients do survive into the seventh or eighth decade. The natural history of bipolar affective disorder in the elderly is unclear although longitudinal studies demonstrate that some bipolar patients have shortening of cycles and increased severity of disease.
What Causes Mood Instablity in Older Bipolar Patients?
Well-controlled bipolar patients become unstable for many reasons. Patients have worsening of symptoms as a result of:
- medication non-compliance
- medical problem
- natural history, i.e., changes in the symptoms over time
- caregiver death
- substance abuse
- inter-current dementia
Elderly bipolar patients who have acute worsening of symptoms need a careful evaluation to exclude delirium. Elderly psychiatric patients exhibit high rates of alcohol abuse and prescription sedative overuse that produce delirium. Agitated, delirious patients can appear manic. Psychoses, agitation, paranoia, sleep disturbance and hostility are symptoms common to both diseases. Delirious bipolar patients will often have a significant drop in the Mini-Mental Examination score from baseline while cooperative mania patients should have steady scores.
Discontinuation of mood-stabilizing medication is a common problem in elderly bipolar patients. Patients discontinue medicine for multiple reasons:
- new medical problem
- death of caregiver and loss of support
- physician discontinuation due to perceived complications from medications.
Blood levels should be regularly monitored on all bipolar patients. Antimanic agents may be discontinued during a serious medical illness during which the patient can no longer take oral medication and these agents should be restarted as soon as possible. Medical physicians should not discontinue antimanic agents for more than two or three days without seeking a psychiatric consultation. Bipolar patients will sometimes discontinue medication when the spouse or caregiver dies and the patient lose psychosocial support mechanisms. Primary care physicians will sometimes discontinue lithium or tegretol because of perceived side effects. Lithium and Tegretol are essential to maintain mood stability for many bipolar patients. Elevated BUN or creatine is not an automatic indication for lithium discontinuation. Patients should have a 24-hour urine collection and patients with creatinine clearances below 50ml per minute, should be referred to a nephrologist for consultation. Many elderly bipolar patients with elevated BUN and creatinine who receive lithium do NOT have lithium-induced nephrotoxicity. Elevated kidney function studies are common in the elderly. Lithium, Tegretol or valproic acid should NOT be discontinued due to medical problems unless an internist or sub-specialist is consulted or an emergency exists.
Consultants should be informed that discontinuation of antimanic agents will probably precipitate a relapse. Acute mania will often destabilize medical problems of elderly bipolar patients. Manic elderly patients who are stressed by psychotic agitation may stop all medications including cardiac medicines, antihypertensives, etc. The clinicians must carefully weigh the medical risk of sustained anti-manic therapy verses the medical risk of acute psychosis. This decision requires clear communication among medical specialists, psychiatrist, patient, and family.