OBJECTIVES: Patients with dementia may be at risk for more and longer hospital stays than those without dementia; requiring disease management. We explore the association between time to subsequent hospitalizations from the index hospitalizations for our dementia and nondementia groups. METHODS: We used administrative claims from 2000-2008 from a large integrated managed care system.  Patients with any dementia diagnosis claim in any year were selected.  From the remainder of patients a matched (on co-morbidities associated with dementia) group of patients of equal size without a dementia diagnosis were selected.   The first hospitalization was the index date.  We used the hospital claims to compare time to the next hospitalization after the index date for the dementia and non dementia groups.  Analysis was with bivariate and multivariate Cox proportional hazards models controlling for demographics and socioeconomics characteristics and co-morbidities. RESULTS: There were 94,874 patients with  60,869 from the dementia and 34,005 from the nondementia groups. The hospitalized dementia group was significantly older (81.2 vs 75.4 years respectively p<0.001). Dementia patients had a significantly longer length of stay (5.4 days, SD=7.93) and more hospitalizations than non-dementia patients (4.8 days; SD=8.17) (p<0.0001).  The Kaplan Meier curve showed that dementia patients had a significantly shorter time between the index and additional hospitalizations (logrank test, p<0.0001).  Age, gender, and most co-morbidities significantly affect time to hospitalizations (p<0.0001).  Increasing age by 1 year increases the relative risk (RR) of hospitalizations by 0.3%.  Being female decreases the RR of hospitalization by 6.9%. Diabetes, CHF, and hypertension increase the RR of hospitalizations by 20.1%, 19.4% and 16.0% respectively.  CONCLUSIONS: Dementia patients had more hospitalizations than non-dementia group and a longer time to their subsequent hospitalizations than did the non-dementia group, even when controlling for other factors.  Disease management might be used to improve the time between and number of hospitalizations for dementia patients.