1 Veterans Affairs Puget Sound Health Care System, Geriatrics Research Education and Clinical Center, Seattle, WA 98108, USA; University of Washington School of Medicine, Division of Gerontology and Geriatric Medicine, Department of Medicine, Seattle, WA 98498, USA.
2 Loma Linda University School of Medicine, Departments of Neurosurgery, Basic Sciences, and Pathology and Human Anatomy, Loma Linda, CA 92354, USA.
3 Veterans Affairs Puget Sound Health Care System, Geriatrics Research Education and Clinical Center, Seattle, WA 98108, USA; University of Washington School of Medicine, Division of Gerontology and Geriatric Medicine, Department of Medicine, Seattle, WA 98498, USA. Electronic address: wabanks1@uw.edu.