Several studies have reported a decline in incidence of dementia which may have large implications for the projected burden of disease, and provide important guidance to preventive efforts. However, reports are conflicting or inconclusive with regard to the impact of gender and education with underlying causes of a presumed declining trend remaining largely unidentified. The Alzheimer Cohorts Consortium aggregates data from nine international population-based cohorts to determine changes in the incidence of dementia since 1990. We will employ Poisson regression models to calculate incidence rates in each cohort and Cox proportional hazard regression to compare 5-year cumulative hazards across study-specific epochs. Finally, we will meta-analyse changes per decade across cohorts, and repeat all analysis stratified by sex, education and APOE genotype. In all cohorts combined, there are data on almost 69,000 people at risk of dementia with the range of follow-up years between 2 and 27. The average age at baseline is similar across cohorts ranging between 72 and 77. Uniting a wide range of disease-specific and methodological expertise in research teams, the first analyses within the Alzheimer Cohorts Consortium are underway to tackle outstanding challenges in the assessment of time-trends in dementia occurrence.

Additional Metadata
Keywords Alzheimer disease, Cohort analysis, Consortium, Epidemiology
Persistent URL dx.doi.org/10.1007/s10654-017-0320-5, hdl.handle.net/1765/102537
Journal European Journal of Epidemiology
Grant This work was funded by the European Commission 7th Framework Programme; grant id fp7/601055 - VPH Dementia Research Enabled by IT (VPH-DARE@IT), This work was funded by the European Commission 7th Framework Programme; grant id h2020/667375 - Common mechanisms and pathways in Stroke and Alzheimer's disease. (CoSTREAM), This work was funded by the European Commission 7th Framework Programme; grant id erc/678543 - Origins of Alzheimer's disease across the life-course (ORACLE)
Citation
Chibnik, L.B, Wolters, F.J, Bäckman, K. (Kristoffer), Beiser, A, Berr, C, Bis, J.C, … Hofman, A. (Albert). (2017). Trends in the incidence of dementia: design and methods in the Alzheimer Cohorts Consortium. European Journal of Epidemiology, 1–8. doi:10.1007/s10654-017-0320-5