Could Alzheimer's disease be detected 15 years earlier?

Global Burden of Disease figures show that in 2019, there were 57.

The neurodegenerative conditions that lead to dementia, especially Alzheimer's disease, are often progressive, developing decades before the patient becomes disabled

What manifestations might be red flags long before Alzheimer's disease is clearly present? To confirm this, a multidisciplinary team from the Paris Brain Institute conducted a large study that analyzed the health records of nearly 80,000 patients

The team found that compared with other patients of the same age, patients who reported Alzheimer's disease had 10 symptoms more frequently in the 15 years before diagnosis, and another 12 symptoms were more common in the 2 years before diagnosis

Screenshot source: The Lancet Digital Health

This study aimed to provide a detailed analysis of potential risk factors prior to diagnosis using a large patient sample and a focus on health conditions identified in primary care

The research team extracted anonymous health information from a database of nearly 40,000 Alzheimer's patients (20,214 patients in the UK, 1 January 1996 - 31 March 2020; 19,458 patients in France, January 1998 4-February 20, 2019), these patients were followed up for at least two years

The research team analyzed three different periods before diagnosis to distinguish risk factors for Alzheimer's disease (10-15 years before diagnosis), early symptoms (2-10 years before diagnosis) and comorbid symptoms (2 years before diagnosis) )

The results showed that, after statistical adjustment, 10 symptoms of Alzheimer's disease were significantly associated with Alzheimer's disease in patients in both countries in the 2-10 years before diagnosis, in other words, presumably early symptoms

Major depressive disorder: associated with a 34% increased odds of AD diagnosis in UK patients; 73% increased odds of AD diagnosis in French patients

Five symptoms remained significantly associated after multivariate analysis, including anxiety, depression, constipation, spondylosis, and memory loss

In the time window of 10-15 years before diagnosis, none of the above symptoms were found to be significantly associated with Alzheimer's diagnosis

In the 0-2 years before the diagnosis, a total of 21 symptoms were significantly related to the diagnosis of Alzheimer's disease, which may be comorbid symptoms of Alzheimer's disease

Next, the research team compared the incidence of various health problems associated with Alzheimer's disease over time in the Alzheimer's disease group and the control group

▲In the AD cohort, the incidence of health problems significantly related to AD, the trend over time (Image source: Reference [1])

The paper concludes that these results provide new evidence of underlying risk factors and early signs associated with Alzheimer's disease, which can be observed in primary care settings, and can be used for primary prevention and treatment of Alzheimer's disease.

The research team is currently expanding the database, adding data from Sweden and Australia for further analysis based on the European Neurodegenerative Disease Research Project

References

[1] Thomas Nedelec, et al.

[2] GBD 2019 Dementia Forecasting Collaborators.
(2022).
IEstimation of the global prevalence of dementia in 2019 and forecasted prevalence in 2050: an analysis for the Global Burden of Disease Study 2019.
The Lancet Public Health, DOI: https:// doi.
org/10.
1016/S2468-2667(21)00249-8

[3] Identification of new risk factors or early signs of Alzheimer's disease.
Retrieved February 23, 2022 from https:// abridged)