Scientists discover alarming rise in early-onset dementia

A new study from Finnish universities explored early-onset dementia in the working-age population, reviewing 12,490 patient records from 2010-2021. The findings showed higher incidence rates than previously reported, with Alzheimer’s being the most prevalent subtype.

Recent research shows an unexpectedly high rate of early-onset dementia in adults under 65, with findings particularly significant for Alzheimer’s disease, challenging previous data on the prevalence of the condition.

A recent large study by the University of Eastern Finland, the University of Oulu and Neurocenter Finland investigated early-onset dementia among the working-age population in Finland. This study is among the largest of its kind worldwide. The results were recently published in Neurologythe official medical journal of the American Academy of Neurology.

Current epidemiological data on early-onset dementia are limited and based on small study cohorts, with no recent data available from Finland. For this study, researchers analyzed the patient data registers of Kuopio and Oulu University Hospitals from 2010 to 2021, looking at all working-age patients diagnosed with dementia during this time period. Both incidence, which is the number of new cases, and prevalence, which is the total number of people affected, were explored. Patient charts for a total of 12,490 individuals were reviewed and classified into diagnostic groups using uniform criteria. The two hospitals diagnose virtually all cases of early-onset dementia in their provinces, making the data very robust.

The incidence of early-onset dementia is higher than previously reported

The study observed higher incidence rates of early-onset dementia than previously reported in international studies. In the 30–64 age group, the incidence of early-onset dementia was 20.5 cases per 100,000 person-years; and 33.7 cases per 100,000 person-years in the 45-64 age group. alzheimer disease was the most prevalent subtype (48%), followed by frontotemporal dementia spectrum disorders (23%) and Lewy body spectrum disorders (6%). These figures are higher than in previous smaller publications in other countries.

“The higher incidence rates observed in our study can be attributed to our methodology, which allowed us to capture almost all cases of EOD in the study areas. In addition, an increased awareness of dementia among the public and healthcare professionals in Finland may also contribute to the high number of diagnosed cases,” says Associate Professor Eino Solje from the University of Eastern Finland, PI study.

“A strength of the present study is that all diagnoses were retrospectively and manually reviewed from the patient records, allowing incorrect diagnoses to be eliminated and also taking into account diagnoses that changed during the follow-up period,” says Solje.

The researchers found that in the working-age population, the incidence of Alzheimer’s disease has steadily increased, while the incidence of other dementias has remained unchanged.

“The incidence of Alzheimer’s disease has almost doubled. This cannot be explained simply by a better diagnosis and seeking treatment earlier, as we did not observe an increase in the incidence of other dementias,” says Associate Professor Johanna Krüger, PI of the study at the University of Oulu, first author of the article. .

A new model of collaboration

The present study is the first of a large project combining exceptionally large real-life patient data with various registries.

The project involves a unique collaboration between the University of Oulu and the University of Eastern Finland, as well as between different scientific disciplines, involving, for example, scientists in medicine and law.

“Combining extensive patient data with various registries enables a higher standard of science. For example, we now see that data from carefully analyzed patient records gives very different results than simple registry-based data,” notes Professor Mikko Aaltonen from the Faculty of Law at the University of Eastern Finland.

The project is also being run in a new way. The research is funded by companies, which also have the opportunity to engage in dialogue within the scientific steering committee of the project, under the coordination of Neurocenter Finland.

“The model makes it possible to mobilize the resources of the private sector in the implementation of scientific projects that will benefit everyone. With Neurocenter Finland coordinating the collaboration between the various parties, researchers can better devote their time to solving scientific problems,” says Eero Rissanen, Director of Neurocenter Finland.

Reference: “Incidence and prevalence of early-onset dementia in Finland” by Johanna Krüger, Mikko Aaltonen, Kalle Aho, Sami Heikkinen, Ave Kivisild, Adolfina Lehtonen, Laura Leppänen, Iina Rinnankoski, Helmi Soppela, Laura Tervonen, Noora-Maria Suhonen, Annakaisa Haapasalo, Anne M. Portaankorva, Anna Mäki-Petäjä-Leinonen, Päivi Hartikainen, Kasper Katisko and Eino Solje, 24 July 2024, Neurology.
DOI: 10.1212/WNL.0000000000209654