Targeting therapy for movement disorders

Abstract

It remains a common misconception that neurologists are physicians who are skilled only in making a diagnosis but who are disinterested in therapy of patients. However, there have been major advances on several neurological fronts in the past 50 years. Therapeutics of Parkinson's Disease and Other Movement Disorders, edited by Mark Hallett and Werner Poewe, is a well organised summary of the state-of–the-art treatments in movement disorders. The book is divided into nine sections covering the major areas in movement disorders: Parkinson's disease (PD) and atypical parkinsonism, tremor, dystonia, and muscle spasms, other hyperkinetic movement disorders, cerebellar, gait, and balance disorders, and psychogenic movement disorders. The editors have assembled a panel of leading international experts as chapter authors within each section, who ably provide the balance between scientific rigour and “personal clinical acumen and therapeutic wisdom”. Each chapter and section is led by a concise summary of disease pathophysiology, followed by a detailed review of treatment. This approach enables understanding of the therapies within a broader mechanistic framework. Rather than simply putting together a list of randomised controlled trials or declaring therapy an evidence-free zone, most of the contributors synthesise the body of current knowledge and present a practical approach to help deal with the immediate needs of the individual patient. Their work is both cause for optimism and sober reflection. James Parkinson recommended “at whatever period of the disease it might be proposed to attempt the cure, blood should be first taken from the upper part of the neck…” as therapy for shaking palsy. The Nobel-prize winning discovery by Arvid Carlsson that dopamine is a neurotransmitter led to dopamine-replacement therapy for PD more than 40 years ago—one of the greatest success stories in neurological therapeutics. Yet this effective symptomatic therapy remains an exception rather than the rule for neurodegenerative diseases, and, almost 200 years on from Parkinson's recommendations, we are still searching for a cure. Most of the chapters cite up-to-date references, but, as inevitably happens with the prolonged process of publishing a book, some findings have been omitted. For example, some of the more recent gene discoveries in familial PD and the link between glucose transporter gene defects and paroxysmal exercise-induced dystonia are not included. Recent randomised, double-blind, controlled studies supporting the use of domperidone as treatment for orthostatic hypotension and macrogol as treatment for constipation in PD, two common non-motor symptoms, escape mention. The chapter on Wilson's disease is written by a recognised authority who strongly advocates avoiding D-penicillamine; however, this treatment remains favoured by other experts and is the only affordable option in many countries. Some practical guidance for those who have need of its use would have been beneficial. The chapter on myoclonus could have been enhanced by more detailed discussion of the importance of neurophysiological characterisation of myoclonus for therapy, and the section on neuroleptic-induced movement disorders could have been improved by a broader discussion of the nosological, diagnostic, and management challenges of neuroleptic malignant syndrome. Overall, this book can be strongly recommended and is an asset to libraries of both movement disorder specialists and general neurologists. Its logical structure, linking therapy with underlying pathophysiology, means that it will remain a useful reference even as new therapies inevitably emerge.