Delusional and aggressive, while playing the lottery

Mr. P’s symptoms stabilized with dival­proex sprinkles and risperidone. There was no evidence of decline in memory, social interaction, or behavior.

EVALUATION Paranoia
On mental status exam, Mr. P has an appropri­ate appearance; he is clean and shaven, with good eye contact. Muscular tone and gait are within normal limits. Level of activity is increased; he exhibits psychomotor agitation. Speech is rapid, over-productive, and loud; thought process shows flight of ideas, and thought associations are circumstantial.

Mr. P has paranoid delusions about the staff trying to hurt him. His judgment is poor, evidenced by an inability to take care of him­self. Insight is minimal, as seen by noncompli­ance with treatment. Mr. P is oriented only to person and place. His mood is anxious; affect is labile.

Complete blood count, comprehensive met­abolic profile, blood alcohol level, urine analy­sis, urine toxicology, electrocardiogram, and CT scan of the head are within normal limits.

Mr. P is given a diagnosis of mood disorder due to general medical condition, psychotic disorder due to general medical condition. The team rules out acute delirium, bipolar I disor­der, and neurodegenerative disorders such as frontotemporal dementia.

Mr. P is maintained on pre-admission medi­cations for his medical conditions. A mood sta­bilizer, divalproex sprinkles, 250 mg/d, is added.

Once on the unit, Mr. P is re-evaluated. Divalproex is increased to 500 mg/d; risperi­done, 0.5 mg/d, is added to address paranoia. Mr. P also receives group and individual psy­chotherapy. He does not participate in neuro­psychological testing, and no single-photon emission CT analysis is done. Mr. P remains in the hospital for 2 weeks. After a family meeting, his daughter says she feels comfortable taking Mr. P home. He follows up in the outpatient clinic and is doing well.

The authors’ observations
Treating geriatric patients with bipolar disorder requires attention to several fac­tors (Table). Older patients might tolerate or metabolize medications differently than younger adults, and therefore may need a different dosage. Older patients are more likely to have comorbid medical conditions and to be taking medications for those ail­ments. Treatment is much more compli­cated for this age group because physicians need to account for possible drug-drug interactions.²¹

A number of medications can be helpful in treating older patients who have bipolar disorder.¹¹ Ongoing research compares lith­ium with anticonvulsants in older bipolar disorder patients to determine which drug has the greatest benefit with the lowest risk of side effects.

Psychotherapy can be a valuable addition to pharmacotherapy in older adults. Some psychotherapy programs are specifically geared to older bipolar disorder patients.^22,23

Use of divalproex sodium in older patients
First, perform baseline laboratory tests: complete blood count, liver function, and electrocardiogram. Initiate divalproex sodium, 250 mg at bedtime, increasing the dosage every 3 to 5 days by 250 mg, with a target dose of 500 to 2,000 mg/d (divided into 2 or 3 doses). Monitor serum levels; levels of 29 to 100 μg/mL are effective and well tolerated. Common side effects include excess sedation, ataxia, tremor, nausea, and, rarely, hepatotoxicity, leuko­penia, and thrombocytopenia.²⁴

Use of lithium in geriatric patients
First, perform baseline laboratory tests: electrolytes, creatinine, blood urea nitro­gen, urine, thyroid stimulating hormone, and electrocardiogram. Starting dosage is 300 mg at bedtime (150 mg for frail cachec­tic patients). Monitor serum levels 12 hours after last dose, adjusting dosage every 5 days until a target serum level of 0.5 to 0.8 mEq/L is reached. Common dosages for geriatric patients are 300 to 600 mg/d, which often can be given as a single bed­time dose. Cautions: When using lithium with a thiazide diuretic or nonsteroidal anti-inflammatory drug, watch for dehy­dration, vomiting, and diarrhea, which will elevate the serum lithium level. Side effects include ataxia, tremor, urinary frequency, thirst, nausea, diarrhea, hypothyroidism, and exacerbation of psoriasis. Once sta­bilized, monitor the serum lithium level, thyroid-stimulating hormone, and kidney function every 3 to 6 months.²⁴

Bottom Line
In geriatric patients, bipolar disorder can present with agitation, irritability, confusion, and psychosis, rather than euphoric mood and grandiosity. When you suspect bipolar disorder in an older patient, first rule out medical causes of symptoms. When selecting treatment, consider comorbid medical conditions and possible drug-drug interactions.