1. Departments of Medicine, College of Physicians and Surgeons, Columbia University Medical Center, New York, NY, USA
2. Departments of Epidemiology, Mailman School of Public Health, Columbia University Medical Center, New York, NY, USA
3. Research Division, Hebrew Home for the Aged at Riverdale, New York, NY, USA
4. Department of Psychiatry, New York University, New York, NY, USA