AAN evidence-based reviews on PD management and treatment

A series of practice parameters from the American Academy of Neurology, recently published in Neurology, describes the evidence-based approach to diagnosis, prognosis, and management of Parkinson disease (PD).The first practice parameter describes the recommendations for the diagnosis and prognosis of new onset Parkinson disease. Based on a systematic review, the authors describe the clinical features that probably distinguish other parkinsonian syndromes from Parkinson disease, which include early falls, poor response to levodopa, and early autonomic dysfunction. Conversely, levodopa or apomorphine challenge and olfactory testing are probably useful in distinguishing PD from other parkinsonian syndromes. Predictive factors for disease progression include older age at onset, associated comorbidities, presentation with rigidity and bradykinesia, and decreased dopamine responsiveness.The second practice parameter provides recommendations on neuroprotective strategies and alternative therapies for PD. It concludes that levodopa does not appear to accelerate disease progression, and that no treatment has been shown to be neuroprotective. It also provides an overview of the evidence on exercise, vitamin or food additives, manual therapy, and speech therapy for PD.A third practice parameter, dedicated to the treatment of motor fluctuations and dyskinesia, concludes that entacapone and rasagiline reduce off time and should be offered for this indication (Level A evidence). Other agents that may also reduce off time include pergolide, pramipexole, ropinirole, and tolcapone (Level B evidence) and apomorphine, cabergolide, and selegiline (Level C evidence). However, the authors conclude that sustained release carbidopa/levodopa and bromocriptine may be disregarded to reduce off time (Level C). Amantadine may be considered to reduce dyskinesia, and deep brain stimulation may be considered to improve motor function and reduce off time.Finally, a practice parameter on the evaluation and treatment of depression, psychosis, and dementia in PD concludes that, although screening tools are available, more specific validated tools are needed. It also concludes that clozapine successfully treats psychosis in PD, and cholinesterase inhibitors are effective for dementia in PD.The author of an accompanying editorial points out that the validity of the practice parameters relies on the strength of the underlying evidence and notes that there is only one Level A recommendation in the series. However, he concludes, "While the immediate impact of these Practice Parameters may be modest, they will influence our clinical research agenda and are likely to have significant long-term consequences."Reference...