1. Intensive Care Unit, University College Hospital, University College London Hospitals NHS Foundation Trust, London, UK
2. Intensive Care Unit, Royal Free Hospital, Royal Free London NHS Foundation Trust, London, UK
3. Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
4. Division of Neurology, Department of Medicine, National University Health System, Singapore
5. Division of Endocrinology, Department of Medicine, National University Health System, Singapore
6. Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, NUHS Tower Block, 1E Kent Ridge Road Level 11, 119228 Singapore
7. Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Neurology, Department of Medicine, National University Health System, Singapore