Current concepts in the management of Parkinson disease

To the Editor: The recent review by Hayes and colleagues1 does not sufficiently emphasise practical approaches to managing the later stages of Parkinson disease (PD).

Nazem and colleagues2 reported active suicidal or death ideation in 30% of patients with PD of mild-to-moderate severity, and an overall rate of major depression of 27.6%. They found that psychiatric symptoms and disorders, especially major depression, rather than PD-related variables, predicted suicidal or death ideation. Only half of the depressed patients were being treated with an antidepressant. Screening for psychiatric disorders should occur on assessment. Skilled counselling is required, and carers need to be well supported, particularly if the patient has intermittent suicidal ideation and a strong wish for the end of life.

Clozapine is the only antipsychotic shown to be effective for treating psychosis in patients with PD.3 If the psychosis is schizophrenia-like, with persistent bizarre delusions and florid hallucinations causing agitation, clozapine can be prescribed in Australia by a registered psychiatrist and the patient can be registered with the clozapine monitoring service. If the patient is started on a very low dose (6.25 mg daily) that is only very gradually increased, side effects can be minimised. Successful use of clozapine enables remission of the psychosis and optimal treatment of motor symptoms.

Mild hallucinations may be tolerated without specific treatment while the patient retains insight. In an open-label study of patients with mild hallucinations comparing no treatment with quetiapine therapy (or clozapine therapy in a minority of cases),4 the rate of progression to hallucinations without insight, or delusional psychosis, was significantly slowed.

Hely and colleagues5 have argued that pathological processes in addition to Lewy body disease may have a role in the appearance of dementia, as age is a better correlate than PD duration. If it is clear that the dementia is a PD dementia, or dementia with Lewy bodies, a cholinesterase inhibitor such as rivastigmine could be prescribed. As rivastigmine is not subsidised on the Pharmaceutical Benefits Scheme in Australia for this indication, a private prescription could be provided in the first instance, and if there was a likelihood of significant Alzheimer disease associated with PD, an authority prescription would be justified.

Hely and colleagues pointed out that, in the later disease stages of PD (at 20 years), less than 50% of patients still see their neurologist. However, the quality of life for PD patients in nursing-home care could still be significantly improved by specialist review by members of a multidisciplinary team on an inpatient, outpatient or outreach basis.