Importance:An estimated 4 to 5 million Americans have Alzheimer disease or another dementia. Objective:To determine the health care utilization and cost outcomes of a comprehensive dementia care program for Medicare fee-for-service beneficiaries. Design, Setting, and Participants:In this case-control study, we used a quasiexperimental design to compare health care utilization and costs for 1083 Medicare fee-for-service beneficiaries enrolled in the University of California Los Angeles Health System Alzheimer and Dementia Care program between July 1, 2012, and December 31, 2015, with those of 2166 similar patients with dementia not participating in the program. Patients in the comparison cohort were selected using the zip code of residence as a sampling frame and matched with propensity scores, which included demographic characteristics, comorbidities, and prior-year health care utilization. We used Medicare claims data to compare utilization and cost outcomes for the 2 groups. Interventions:Patients in the dementia care program were comanaged by nurse practitioners and physicians, and the program consisted of structured needs assessments of patients and their caregivers, creation and implementation of individualized dementia care plans with input from primary care physicians, monitoring and revising care plans, referral to community organizations for dementia-related services and support, and access to a clinician for assistance and advice 24 hours per day, 7 days per week. Main Outcomes and Measures:Admissions to long-term care facilities; average difference-in-differences per quarter over the 3-year intervention period for all-cause hospitalization, emergency department visits, 30-day hospital readmissions, and total Medicare Parts A and B costs of care. Program costs were included in the cost estimates. Results:Program participants (n = 382 men, n = 701 women; mean [SD] age, 82.10 [7.90] years; age range 54-101 years) were less likely to be admitted to a long-term care facility (hazard ratio, 0.60; 95% CI, 0.59-0.61) than those not participating in the dementia care program (n = 759 men, n = 1407 women; mean [SD] age, 82.42 [8.50] years; age range, 34-103 years). There were no differences between groups in terms of hospitalizations, emergency department visits, or 30-day readmissions. The total cost of care to Medicare, excluding program costs, was $601 less per patient per quarter (95% CI, -$1198 to -$5). After accounting for the estimated program costs of $317 per patient per quarter, the program was cost neutral for Medicare, with an estimated net cost of -$284 (95% CI, -$881 to $312) per program participant per quarter. Conclusions and Relevance:Comprehensive dementia care may reduce the number of admissions to long-term care facilities, and depending on program costs, may be cost neutral or cost saving. Wider implementation of such programs may help people with dementia stay in their communities.