Background: The further development of public-health approaches for the prevention of dementia requires estimates of the number of people with dementia, trends in incidence and prevalence, and the potential impact of preventive measures.
Methods: The projections described here are based on incidence and prevalence data for Europe and on current and projected population figures from the German Federal Statistical Office. Four scenarios were calculated on the basis of two different population projections and the assumption of either stable or declining prevalence. Data from the German Aging Survey were used to estimate the prevention potential for eleven potentially modifiable risk factors for dementia. Weighting factors were determined to adjust for correlations between risk factors.
Results: Approximately 1.8 million people were living with dementia in Germany as of December 31, 2021; the number of new dementia cases in 2021 is estimated at 360 000 to 440 000. In 2033, depending on the scenario, 1.65 to 2 million people aged 65 and older may be affected; we consider likelihood of the lower end of this range to be very low. It is estimated that 38% of these cases are associated with 11 potentially modifiable risk factors. A 15% reduction in the prevalence of risk factors could potentially decrease the number of cases by up to 138 000 in 2033.
Conclusion: We assume that the number of people with dementia in Germany will increase, but there is considerable prevention potential. Multimodal prevention approaches to promote healthy aging should be further developed and put into practice. Better data are needed on incidence and prevalence of dementia in Germany.