An 85-year-old man is evaluated at a nursing home due to increasing agitation. The patient has dementia and has been residing at the facility for several years. At baseline, he can communicate his needs but does not recognize his caregivers and requires assistance with all activities of daily living. According to the staff, the patient usually becomes agitated in the evening. He has been receiving low doses of haloperidol or olanzapine as needed, but they have not controlled his symptoms, and the episodes of agitation have become somewhat more frequent recently. He has had no fever, cough, abdominal pain, urinary symptoms, or change in appetite. Medical records indicate a history of hypertension but no other medical conditions. The patient takes no additional medications. Temperature is 37 C (98.6 F), blood pressure is 130/70 mm Hg, and pulse is 78/min. He appears to be comfortable and is oriented to self only. Lungs are clear to auscultation, and heart sounds are normal. The abdomen is soft and nontender with normoactive bowel sounds. Neurologic examination shows mild resting hand tremors and rigidity of both arms. There is no extremity edema or rash. Which of the following is the most appropriate next step in management of this patient?
Antipsychotics & risk for drug-induced parkinsonism | ||
Antipsychotic | Parkinsonism risk | D2 antagonism |
Haloperidol | +++ | High |
Risperidone | ++ | High |
Olanzapine | ++ | Intermediate |
Clozapine | + | Low |
Quetiapine | + | Low |
Pimavanserin | + | None |
D2 = dopamine. | ||
This elderly man with dementia and increasing agitation, for which he takes multiple antipsychotics, now has upper extremity resting tremors and rigidity, findings suggestive of drug-induced parkinsonism due to antipsychotics (eg, haloperidol, olanzapine).
In patients with dementia, neuropsychiatric symptoms (eg, disorientation, agitation, aggression) are common and may become more pronounced, particularly at night (sundowning), as the disease progresses. Treatment options include behavioral interventions, antidementia drugs, and antidepressants. Although antipsychotics are sometimes used, particularly in severe aggression, they are associated with increased mortality and multiple adverse effects, including extrapyramidal symptoms (eg, iatrogenic parkinsonism, akathisia, dystonia). Secondary parkinsonism results in cogwheel rigidity, pill-rolling resting tremors, masked facies, shuffling gait, and bradykinesia.
In this patient who has adverse effects with low antipsychotic doses, increasing the antipsychotic regimen would likely worsen his parkinsonism symptoms, particularly if haloperidol is used (Choice C). Because they also have been ineffective in managing his agitation, the causative medications should be discontinued in favor of behavioral interventions (eg, sensory activities, music therapy, distraction techniques, communication skills training for caregivers). When antipsychotics are used, it should be for patients who have legitimate safety concerns toward themselves or caretakers (ie, aggression); their use should be minimized as much as possible.
(Choice A) Changing olanzapine to risperidone would likely worsen this patient's secondary parkinsonism because risperidone has greater D2 receptor antagonism compared to olanzapine; the greater the D2 receptor antagonism, the greater the likelihood for inducing parkinsonism.
(Choice D) Carbidopa-levodopa is used to treat motor disturbances in primary Parkinson disease. However, Parkinson disease begins with motor symptoms, and patients develop dementia late in the disease course, unlike this patient who developed parkinsonian features years after dementia. Carbidopa-levodopa is not indicated in secondary parkinsonism caused by antipsychotics.
(Choice E) In patients with suspected drug-induced parkinsonism, the diagnosis is primarily clinical, such as in this patient with bilateral upper extremity tremors and rigidity who takes 2 antipsychotics known for this adverse effect. In these patients, initial management is to discontinue the causative medication. MRI is not indicated in the initial work-up of parkinsonism.
Educational objective:
Neuropsychiatric symptoms are common in patients with dementia; treatment includes behavioral interventions, antidementia drugs, and antidepressants. Antipsychotics are sometimes used but are associated with increased mortality and multiple adverse effects, including extrapyramidal symptoms. If possible, antipsychotics should be discontinued in patients who develop adverse effects.