Analysis of the correlation between clinical and neuroimaging markers and response to memantine therapy in patients with mild Alzheimer's dementia (KIPRIDA open observational study)

Resume. The use of memantine has long been the basis of modern symptomatic therapy for patients with moderate and severe dementia with Alzheimer's disease. At the same time, the effectiveness of the drug in the treatment of mild dementia in this pathology remains the subject of wide discussion.The purpose of this open-label observational study is to analyze the relationship between clinical, neuroimaging markers and response to memantine therapy in patients with mild Alzheimer's dementia. Materials and methods. 40 patients (66.7 [60.8; 71.5] years old) received memantine at a dose of 20 mg/day for 3 months. The MRI parameters (overall severity of cerebrovascular changes, Medial Temporal lobe Atrophy (MTA)), the results of the Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MCA), Addenbrooke's Cognitive Examination, revised (ACE-R), Interlocking finger test (IFT), Free and Cued questionnaires were analyzed Selective Reminding Test – Immediate Recall (FCSRT-IR), Global Rating of Change Scale (GROC), the presence and characterization of side effects. Multiple linear regression models with calculation of β-coefficients were used to analyze the relationship between the response to therapy and the main analyzed parameters. Results. A significant improvement in cognitive function according to a number of tests was recorded after 2 months of treatment (MoCA, IFT, MMSE). Significant improvement in the ACE-R questionnaire (78.4 ± 2.7 vs 83.1 ± 2.7 points) was noted after 3 months of therapy. No significant changes in FCSRT-IR values were recorded during the follow-up period. The majority of patients regarded the improvement from the therapy as "moderate" and "pronounced" (GROC: 26/65%). There was no refusal of further treatment due to the development of adverse events. The most significant factors influencing the success of memantine therapy were OVCI (-0.552 (-0.034–0.814), MTA (-0,417 (-0,015–0,811)), the presence of diabetes mellitus (0.481 (0.028–0.825)) and urinary disorders (-0,414 (-0,074–0,997)). Conclusions. Short-term use of memantine in the treatment of mild Alzheimer's type dementia is effective and safe. The presence of concomitant marked atrophy of the medial frontal lobe, significant cerebrovascular changes according to MRI data, as well as urinary disorders are negative predictors of successful treatment of cognitive disorders, while in patients with diabetes mellitus, the effectiveness of memantine treatment was more pronounced.