Subjects with possible or probable Alzheimer's disease who live alone are more likely to be women, and more likely to be poor than those living with others. They are also older and have milder cognitive impairments and a shorter disease duration. Living arrangement is a significant predictor of service utilization even with other factors held constant. Subjects living alone were less likely to use medical services such as physicians and hospitals, and more likely to use services such as homemaker chore and home-delivered meals. In addition, they were more likely to use no services than those living with others.