OBJECTIVES: Early onset dementia (EOD) describes the occurrence of dementia before the age of 65. To meet patients’ medical care needs, it is crucial to be aware of and understand the epidemiology of patient groups that develop the disease at an atypically early age. This retrospective observational study aims to capture trends in prevalence at general practitioners (GPs) in Germany by comparing prevalence from 2010-2013 to 2020-2023.

METHODS: Electronic medical records of 1,293 office-based GP practices in Germany, encompassing 5.9 million patients aged 18-64 from the IQVIA™ Disease Analyzer, were used for the analysis. The prevalence was calculated for all-cause dementia patients aged 18-64, divided by all individuals with at least one visit to these physicians. Additionally, the prevalence of mild cognitive impairment (MCI) was evaluated.

RESULTS: The prevalence of EOD decreased from 0.12% in 2010-2013 to 0.09% in 2020-2023 in the total cohort (p<0.001), while the prevalence of MCI increased from 0.02% in 2010-2013 to 0.04% in 2020-2023 (p<0.001). The largest reduction in EOD prevalence over time was observed in the age group 60-64 years, decreasing from 0.42% to 0.33% (p<0.001), followed by the age group 50-59 years, which decreased from 0.19% to 0.14% (p<0.001). The prevalence of MCI increased from 0.04% to 0.11% in the age group 60-64 years and from 0.03% to 0.07% in the age group 50-59 years.

CONCLUSIONS: The results indicate a decrease in EOD and an increase in MCI prevalence. As MCI has become a focus of clinical and epidemiological research in the last decade, physicians may recognize and code MCI more often and dementia less frequently in patients aged 18-64 years. Further research is needed on the role played by diagnosing and coding conditions like EOD and MCI in routine care.