1. Institute of Psychological Medicine and Clinical Neuroscience, Cardiff University and University Hospital of Wales, Cardiff, UK; Department of Neurology, University Hospital of Wales, Cardiff, UK
2. Department of Respiratory Medicine, University Hospital Llandough, Llandough, UK
3. Department of Respiratory Medicine, Royal Gwent Hospital, Newport, UK
4. Department of Neurology, Royal Gwent Hospital, Newport, UK
5. Department of Neurology, Addenbrooke’s Hospital, Cambridge, UK