Division of Brain Sciences (T.T., R.N., P.M.M.), Department of Medicine, Imperial College, London; St Edmund Hall (C.S., P.M.M.), Oxford University, Oxford, UK; MRC-NIHR National Phenome Centre (M.D., M.G.-R., M.R.L.), Department of Surgery and Cancer, Imperial College; University College London Queen Square Institute of Neurology (A.H., H.Z.); UK Dementia Research Institute, University College London (A.H., H.Z.), London, UK; Department of Psychiatry and Neurochemistry (H.Z.), Institute of Neuroscience and Physiology, the Sahlgrenska Academy, the University of Gothenburg; Clinical Neurochemistry Laboratory (H.Z.), Sahlgrenska University Hospital, Mölndal, Sweden; and UK Dementia Research Institute at Imperial College (P.M.M.), London.