BRIEF REPORTS

Greater Risk of Dementia When Spouse Has Dementia? The Cache County Study
[See editorial comments by Dr. Peter P. Vitaliano, pp 976–978]

Maria C. Norton, PhD,abc Ken R. Smith, PhD,de Truls Østbye, MD, PhD,fgh JoAnn T. Tschanz, PhD,bc Chris Corcoran, ScD,ci Sarah Schwartz, MS,ci Kathleen W. Piercy, PhD,ac Peter V. Rabins, MD, MPH,j David C. Steffens, MD,k Ingmar Skoog, MD, PhD,l John C. S. Breitner, MD, MPH,mn Kathleen A. Welsh-Bohmer, PhD,g for the Cache County Investigators

OBJECTIVES: To examine the effects of caring for a spouse with dementia on the caregiver’s risk for incident dementia. DESIGN: Population-based study of incident dementia in spouses of persons with dementia. SETTING: Rural county in northern Utah. PARTICIPANTS: Two thousand four hundred forty-two subjects (1,221 married couples) aged 65 and older. MEASUREMENTS: Incident dementia was diagnosed in 255 subjects, with onset defined as age when subject met Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised, criteria for dementia. Cox proportional hazards regression tested the effect of time-dependent exposure to dementia in one’s spouse, adjusted for potential confounders. RESULTS: A subject whose spouse experienced incident dementia onset had a six times greater risk for incident dementia as subjects whose spouses were dementia free (hazard rate ratio (HRR) 5 6.0, 95% confidence interval (CI) 5 2.2–16.2, Po.001). In sex-specific analyses, husbands had higher risks
From the aDepartment of Family, Consumer, and Human Development; b Department of Psychology; cCenter for Epidemiologic Studies; dDepartment of Family and Consumer Studies; eHuntsman Cancer Institute, University of Utah, Salt Lake City, Utah; fDepartment of Community and Family Medicine; g Joseph and Kathleen Bryan Alzheimer’s Disease Research Center, Duke University Medical Center, Durham,