Incidence of dementia in the German Heinz Nixdorf Recall study over 20 years.

INTRODUCTION

The aim of the study was to estimate the population-based dementia incidence in Germany over a period of two decades.

METHODS

We analyzed data from 4814 participants of the population-based Heinz Nixdorf Recall study (49.8% men, 45-75 years at baseline period 2000-2003), who have been monitored for the occurrence of cognitive decline and dementia. We calculated the cumulative incidence of dementia and its major subtypes and the incidence rate per 1000 person-years over two decades.

RESULTS

During a median follow-up of 18.2 (Q1-Q3: 11.3-20.6) years, a total of 298 participants (6.2%) developed dementia (22.1% Alzheimer´s disease, 23.5% vascular dementia, 15.1% mixed dementia, 9.1% other dementia, 30.2% unspecified). The overall incidence rate was 3.9 per 1000 person-years.

DISCUSSION

Our study is the only current population-based study in Germany that estimates the incidence of dementia. In order to reduce the high proportion of unspecific dementia diagnoses, diagnostics urgently need to be improved.

HIGHLIGHTS

New data on the incidence of dementia in Germany in participants ≥45 years of age.Participants have been monitored for dementia incidence over two decades.The overall incidence in our cohort was 3.9 per 1000 person-years.Many patients had unspecific dementia diagnoses in their medical records.Further diagnostic evaluation should be available for all dementia patients.