1 Department of Neurology, Lewisham and Greenwich NHS Foundation Trust, London, UK; UCL Queen Square Institute of Neurology, London, UK.
2 Department of Neurology, Kings College Hospital NHS Foundation Trust, London, UK.
3 Department of Geriatric Medicine, Stroke and Palliative Care, Lewisham and Greenwich NHS Foundation Trust, London, UK.
4 Department of Neurology, Lewisham and Greenwich NHS Foundation Trust, London, UK; UCL Queen Square Institute of Neurology, London, UK. Electronic address: eoin.mulroy@nhs.net.