Problems in the treatment of Parkinsonism

Antipsychotic-Induced movement disorders in the elderly: epidemiology and treatment recommendations

We reviewed the epidemiological aspects of antipsychotic-induced movement disorders as they pertain to older patients. The incidence and prevalence of drug-induced parkinsonism and tardive dyskinesia (TD) are significantly greater in the older patient than in the younger patient whereas akathisia seems to occur evenly across the age spectrum and dystonia is uncommon among older patients. The literature on risk factors associated with treatment-emergent movement disorders is highly variable. Treatment practices vary across the age range and the interaction between age and antipsychotic dosage confounds our understanding of the relative importance of treatment-related risk factors. However, there is general agreement that pre-existing extrapyramidal signs (EPS) increase the vulnerability of the patient to developing significant drug-induced movement disorders. Elderly patients with dementia are at greater risk than patients without dementia for persistent drug-induced EPS. Management of drug-induced movement disorders in the older patient requires careful consideration of the contraindications imposed by such agents as anticholinergics and beta-blockers. At present, well-controlled double-blind studies of second-generation antipsychotics such as clozapine, risperidone. olanzapine or quetiapine for reducing the risk of treatment-emergent movement disorders in the elderly have not been published. However, open-label studies of atypical antipsychotics demonstrate a markedly lower incidence of both EPS and TD compared with conventional antipsychotic treatment in the elderly. There is emerging literature in support of atypical antipsychotics for the treatment of existing drug-induced movement disorders. More controversial is the use of adjunctive antioxidants in newly treated patients who are vulnerable to drug-induced movement disorders. While the evidence is mixed in support of antioxidants for the treatment of TD, the possibility remains that prophylactic use of antioxidants may help reduce the incidence of TD. The development of a drug-induced movement disorder often reduces the quality of life in an elderly patient. Effective pharmacological management requires cooperation from the patient and family, which can be fostered early in the patient's care through proper informed consent. The risks and benefits of antipsychotic treatment in the elderly patient need to be communicated to the patient and family. At the present time, there is no consistently effective treatment for patients with TD once it develops. Therefore, attention should focus on its prevention and close monitoring.

Drug-induced parkinsonism and other movement disorders

This is a review of reserpine, haloperidol, and various phenothiazines that produce parkinsonism and other movement disorders. The by-products of illicit meperidine synthesis, MPTP and its more sinister companion, MPP, are also discussed. Movement disorders, transient or fixed, frank parkinsonism and/or dyskinesia, due to a variety of other medications and toxic agents are included. These are methanol, lithium, methyldopa, antimetabolites, antidepressants, sympathomimetic anorexiants, some types of antihistamines, and various combinations of agricultural chemicals.

Flunarizine-induced parkinsonism in the elderly

Twenty-seven patients (19 women and 8 men, ages 63 to 88 years; mean, 74 years) displayed mild to moderate parkinsonism and altered ballistic motor performances during long-term flunarizine treatment. One month after, flunarizine withdrawal, 20 patients showed clear-cut improvements in both clinical features and ballistic motor performances; a complete recovery within 6 months was observed in all these patients but one, who still showed very mild slowness of movement. On the other hand, seven patients showed little clinical improvement and still maintained markedly altered ballistic motor performances 1 month after drug withdrawal. At the 2-month follow-up assessments, either they did not improve further or they deteriorated; they were successfully treated with L-dopa and, despite the ameliorations, after 12 to 24 months they still have definite parkinsonian syndrome. The authors conclude that (1) flunarizine, even at the recommended dose (10 mg daily), can induce reversible parkinsonism, at least in subjects older than 60; (2) the persistence of a marked symptomatology 2 months after flunarizine withdrawal should lead to starting treatment with antiparkinsonism drugs; (3) the study of ballistic movements is proposed as a useful tool for objective quantification and early detection of bradykinesia.

Diagnosis and epidemiology of Parkinson's disease

The diagnosis of Parkinson's disease is purely a clinical diagnosis. The most common types of diagnostic error are a failure either to recognize the early, or unusual symptoms, or to differentiate other tremors and extrapyramidal syndromes from Parkinson's disease. The prevalence of Parkinson's disease is increasing. This has resulted from the reduction of the excess mortality by levodopa treatment. In the near future, there will be more older parkinsonian patients with a more prolonged duration of the disease.