1. Department of Medicine, National University Hospital , Singapore 119228 , Singapore
2. Yong Loo Lin School of Medicine, National University of Singapore 117597 , Singapore
3. Division of Endocrinology , Department of Medicine, , Singapore 119228 , Singapore
4. National University Hospital , Department of Medicine, , Singapore 119228 , Singapore
5. Fast and Chronic Programmes, Alexandra Hospital , Singapore 159964 , Singapore
6. Division of Advanced Internal Medicine , Department of Medicine, , Singapore 119228 , Singapore