• PARKINSON-S DISEASE

Two questions central to the management of early Parkinson's disease are when to treat and with what to treat. When to treat remains controversial, with the available medications for Parkinson's disease showing no definite evidence of any disease-modifying effect despite some reports of improvements in quality of life in those treated early in the disease course.1 As for what drug to use in early Parkinson's disease, there is little available comparative evidence; practice varies enormously among neurologists and geriatricians, reflecting the inherent uncertainties of what constitutes the best treatment overall.

The three main classes of first-line treatment for Parkinson's are L-dopa, dopamine agonists and monoamine oxidase-B inhibitors. A number of factors influence the decision in individual patients. L-dopa is generally preferred in patients with:

• increasing biological age.

• associated co-morbidity.

• more severe motor symptoms.

‘Dopa-phobia’ leads many clinicians to avoid using L-dopa in young-onset Parkinson's disease in an attempt to delay the onset of motor fluctuations and dyskinesias. However, increasing recognition of the complications of dopamine agonists—including impulse-control disorders in up to 39% of patients2—has tempered enthusiasm for their use, especially in young-onset Parkinson's disease.

Guidelines from the UK's National Institute for Health and Care Excellence (NICE, 2006) and from the Scottish Intercollegiate Guidelines Network (SIGN, 2009) find no single ‘first line’ treatment has a consistent advantage over any other; however, there have been no large-scale randomised trials of all three therapies until now.

The results of the long-awaited early stage PD MED study (Lancet3 2014) have now been published nearly 2 years after initial outline results were presented in late 2012 in Shanghai. This unusual delay led to a barrage (almost ‘overkill’) of formal debates at meetings, and less formal, though no-less-heated discussions about what the results would mean for patients and clinicians. Without the full …