increasing number of persons reach very high age but few studies have investigated their drug use patterns.
to compare drug use among persons with Alzheimer's disease (AD) aged =90 years to persons without AD with similar age and to younger persons with AD.
register-based data were from the MEDALZ cohort including all community-dwelling persons diagnosed with AD 2005-11 in Finland. They were identified from Special Reimbursement register. One comparison person without AD was matched with age-, gender- and region of residence. Persons with AD were divided to those aged =90 years (N = 3,319) and