Background Lifestyle has previously been associated with the onset of Alzheimer's disease (AD) in the typically developing population, but research investigating this association in Down syndrome (DS) is limited. Method Adults with DS and AD (n = 27) were compared to adults with DS without AD (n = 30) on physical activity, diet, weight, where participants currently lived, where participants had lived for the majority of their lives, educational attainment, occupational attainment and cognitive activity. Results There was a significant difference between samples on where participants currently lived, with the majority of the clinical sample living in institutionalized settings and the majority of the control sample living in independent/supported living settings. This may reflect a tendency to move people once they start to deteriorate which, if correct, is contrary to clinical recommendations that people with AD should be supported to “die in place.” Conclusions Further research into the way in which lifestyle factors, particularly living environment, could contribute to the increased risk of AD in adults with DS is required. This may support interventions aimed at preventing or delaying the onset of the disease.