The research, published in the journal Neurology, analysed 350 patients from a cohort at the Hospital Clínic with a diagnosis of Alzheimer's disease (AD) or dementia with Lewy bodies (DLB). The study combined detailed neuropsychological assessments, biomarkers in cerebrospinal fluid and blood, and up to two years of longitudinal follow-up, allowing for the precise characterization of patients’ diagnosis and cognitive progression.
The results confirm that the two diseases present distinct profiles: while Alzheimer’s disease is characterized by memory impairment, dementia with Lewy bodies is more commonly associated with attentional and visuospatial function deficits. However, when both pathologies coexist, the profile changes from the moment of diagnosis, with greater overall cognitive impairment and a faster progression of the disease, particularly in patients with Alzheimer’s disease.
“Our results demonstrate that the presence of mixed pathologies generates more complex and heterogenous cognitive profiles, which cannot be explained if we consider only a single disease,” says Adrià Tort‑Merino, first author of the study. “This points to the need to incorporate comprehensive neuropsychological assessments that allow for the identification of these combinations in clinical practice.”
The study is led by researchers Albert Lladó and Mircea Balasa, with Adrià Tort‑Merino and Diana Esteller‑Gauxax as first authors, and it reveals that comorbidity is a key factor often underestimated in clinical practice. In this regard, the researchers highlight the fact that detecting these combinations of pathologies during a patient’s lifetime is essential in order to better anticipate the patient’s’ progression.
According to Diana Esteller‑Gauxax, “detecting the presence of multiple pathologies during a patient’s lifetime can help both the doctor and the patient with clinical decision-making. Moreover, this information allows us to move towards a more personalized medicine.”
The results also have significant implications for research. In a context where new treatments for neurodegenerative diseases are being developed, the presence of copathology can influence therapeutic response and the interpretation of clinical trial results. For this reason, the authors underline the need to improve the stratification of participants in these studies.
Overall, the work demonstrates that the cognitive profiles and trajectories of dementias depend on the underlying pathology, and highlights the value of an integrated approach combining neuropsychological assessment and biomarkers. This strategy is essential for identifying mixed pathologies during a patient’s lifetime and advancing towards precision medicine in dementia.
Study of reference
Tort-Merino, Adrià et al. Neuropsychological Profile and Cognitive Trajectories of Patients With Biomarker Evidence of Alzheimer Disease or Dementia With Lewy bodies. Neurology. https://doi.org/10.1212/WNL.0000000000218201
