UC Irvine

Comorbidites resulting in hospitalization are important to document in persons developing dementia in order to better understand the progression and burden of the disease. In this study we investigated rates and predictors of hospitalizations in 3,602 participants of the Cardiovascular Health (CHS) Cognition Study evaluated for dementia during 1992-99. Hospitalizations were verified by medical or HCFA records. Unconditional logistic regression was used to estimate the increased risk of hospitalization by cognitive status and forward stepwise regression identified predictors. Average age of the cohort was 75.1 years. Using data collected prospectively in the CHS including a cerebral MRI, 577 participants were classified with mild cognitive impairment (MCI), and 480 with incident dementia including 245 with AD, 62 with VaD, and 151 with mixed dementia (both AD and VaD). During 5.4 years of follow-up, more persons with cognitive problems were hospitalized: 64% with normal cognition, 75% with MCI, 77% with AD, 84% with mixed dementia and 98% of those with VaD (p < .001). Adjusted for age, gender and race, persons with dementia were more than twice as likely to be hospitalized (OR: 2.3, 95% CI: 1.7-2.9) compared to those with normal cognition. Those with MCI were at a 70% increased risk of hospitalization (OR: 1.7, 95% CI: 1.4-2.2). Persons hospitalized at least once were hospitalized an average of 3.8 times during follow-up if classified with dementia (3.2 with AD, 4.6 with VaD) compared to 3.2 times for those with MCI and 2.7 times for those with normal cognition. The rate of total hospitalization for those with normal cognition was 297 per 1000 person- years, 432 for persons with MCI and 1049 for incident dementia including 842 for AD, 1690 for VaD, and 1120 for mixed dementia. Adjusted for age and cognition, predictors of hospitalization included race, gender, site, presence of cardiovascular disease, low ankle-arm index, difficulty with ADLs, greater carotid intima-media thickness, walking speed, self-perceived health, and weight. Because the num-ber and length of hospitalizations increase as cognition declines, care-ful observation and additional preventive care may help reduce this burden.