Early-onset dementia: New study reveals higher incidence rates
A groundbreaking study from Finnish researchers uncovers alarming trends in early-onset dementia among working-age adults, with Alzheimer’s disease cases nearly doubling over the past decade.
In a landmark study published in the journal Neurology [1], researchers from the University of Eastern Finland, the University of Oulu, and Neurocenter Finland have shed new light on the prevalence and incidence of early-onset dementia (EOD) in Finland’s working-age population. The study, which analysed data from 2010 to 2021, reveals higher incidence rates than previously reported in international studies, raising concerns about the growing impact of dementia on younger adults.
Methodology and findings
The research team conducted an extensive review of patient data registries from Kuopio and Oulu University Hospitals, examining the records of 12,490 individuals diagnosed with dementia between the ages of 30 and 64. This comprehensive approach allowed for a more accurate representation of EOD cases in Finland, as the two hospitals diagnose virtually all cases in their respective provinces.
The study found that the incidence of early-onset dementia in the 30-64 age group was 20.5 cases per 100,000 person-years, increasing to 33.7 cases per 100,000 person-years in the 45-64 age group. These figures are notably higher than those reported in previous smaller studies from other countries.
Associate Professor Eino Solje of the University of Eastern Finland, the study’s principal investigator, commented on the findings: “The higher incidence rates observed in our study may be attributed to our methodology, which allowed us to capture nearly all EOD cases from the study areas. Additionally, heightened awareness of dementia among the public and healthcare professionals in Finland may also contribute to the high number of diagnosed cases.”
Diagnostic breakdown
The researchers identified Alzheimer’s disease as the most prevalent subtype of EOD, accounting for 48% of cases. This was followed by frontotemporal dementia spectrum disorders at 23% and Lewy body spectrum disorders at 6%. Importantly, the study revealed a consistent increase in the incidence of Alzheimer’s disease over the study period, while the incidence of other dementias remained stable.
Docent Johanna Krüger, principal investigator at the University of Oulu and first author of the article, highlighted this alarming trend: “The incidence of Alzheimer’s disease nearly doubled. This cannot be explained simply by better diagnostics and seeking of treatment earlier, as we did not see an increase in the incidence of other dementias.”
Strengths of the study
One of the key strengths of this research lies in its meticulous methodology. As Professor Solje explained: “A strength of the present study is that all diagnoses were retrospectively and manually reviewed from patient charts, allowing for the removal of incorrect diagnoses and also the consideration of diagnoses that changed during the follow-up period.”
This approach ensures a higher level of accuracy in the reported incidence and prevalence rates, providing a more reliable foundation for future research and policy decisions.
Implications for healthcare and society
The findings of this study have significant implications for healthcare systems and society at large. The higher-than-expected incidence rates of EOD, particularly the dramatic increase in Alzheimer’s disease cases, suggest a growing need for specialised care and support services for younger adults affected by dementia.
Additionally, the impact on the workforce and families of those diagnosed with EOD cannot be understated. As more working-age adults are affected by dementia, there may be a need for increased workplace accommodations, earlier retirement options, and enhanced support systems for caregivers.
A new model for collaboration
This study represents the first output from an innovative collaborative project that combines extensive real-life patient data with various registries. The project brings together researchers from different disciplines, including medicine and law, fostering a multidisciplinary approach to understanding EOD.
Professor Mikko Aaltonen from the University of Eastern Finland Law School emphasised the value of this approach: “Combining extensive patient data with various registries enables a higher standard of science. For instance, we are now seeing that data from carefully analysed patient charts yields very different results than mere registry-based data.”
Future directions
The research team’s findings pave the way for further studies into the causes and consequences of early-onset dementia. The collaborative model employed in this project, which includes funding and dialogue with private sector companies under the coordination of Neurocenter Finland, may serve as a template for future research initiatives.
Eero Rissanen, Director of Neurocenter Finland, highlighted the benefits of this approach: “The model makes it possible to leverage private sector resources in the implementation of scientific projects that will benefit all. With Neurocenter Finland coordinating collaboration between the different parties, researchers can better devote their time to solving scientific problems.”
As research in this field continues, it is clear that early-onset dementia represents a growing challenge for healthcare systems, policymakers, and society as a whole. The findings from this Finnish study underscore the urgent need for increased awareness, improved diagnostic capabilities, and enhanced support systems for those affected by EOD.
Reference:
- Krüger, J., et al. (2024). Incidence and Prevalence of Early Onset Dementia in Finland. Neurology. https://doi.org/10.1212/WNL.0000000000209654
