1Geriatric Medicine, Radboud university medical center, Nijmegen, Netherlands, 2Radboud Alzheimer Centre, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, Netherlands, 3Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, Netherlands, 4Paediatrics, Radboud university medical center, Nijmegen, Netherlands, 5Nutricia Research, Nutricia Advanced Medical Nutrition, Utrecht, Netherlands