Participants with none of the three risk factors were expected to live 30.1 dementia free years. Among those who did develop dementia, participants with no risk factors lived a mean of 4.1 years with it, against 3.0 years for those with three. Among people with all three risk factors, white participants averaged 19.6 years compared with 16.0 for Black participants. Prior work established that midlife vascular risk factors raise dementia risk. High blood pressure, diabetes, and current smoking, measured in midlife.