Is the risk of developing Alzheimer's disease really higher in rural areas? A multilevel longitudinal study of 261,669 Australians aged 45 years and older tracked over 11 years

Cross-sectional studies of Alzheimer's disease tend to report higher risk in 'rural' areas. Multilevel longitudinal analysis of 261,669 participants in the Sax Institute's 45 and Up Study was conducted, tracking incidence of Alzheimer's disease defined by the first cholinesterase inhibitor prescription via linked records from the Department of Human Services in Australia. Alzheimer's disease was diagnosed in 3046 participants over 11 years. Adjusting for age, gender, education, income and area disadvantage, Alzheimer's disease risk was lower in 'outer regional and remote areas' (incident rate ratio 0.81, 95%CI 0.67-0.97) compared with 'major cities'. Further research on environmental factors is warranted.