1. Department of Pathology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
2. King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia
3. College of Medicine, King Saud University, Riyadh, Saudi Arabia
4. Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia
5. Department of Medicine, Geriatric Division, University of British Columbia, Vancouver, Canada
6. General Administration of Home Health Care, Therapeutic Affairs Deputyship, Ministry of Health, Riyadh, Saudi Arabia