Introduction: Mild cognitive impairment (MCI) is a cognitive disturbance in which intensity is not enough to be classified as dementia and does not affect significantly the functioning or activities of daily living. The MCI has a progression rate to Alzheimer-type dementia (ATD) related to different factors.
Aim: To evaluate the association between the presence of psychological and behavioural symptoms (PBS) with progression to ATD en MCI subjects.
Patients and methods: We evaluated 318 patients with MCI assessed in a Dementia Unit of Catalonia between 1998 to 2002 who were followed five years after the MCI diagnosis. We determined the PBS presence, those classified as affective, behavioural and psychotic symptoms. We also assessed sociodemographic aspects and the ApoE genotype.
Results: The mean age was 74 +/- 7.87 years-old, 56.7% presented PBS, with affective (53%), behavioural (32.2%) and psychotic symptoms (14.8%). In the study, 32.1% progressed to ATD. We found association between the presence of PBS and the progression to ATD (OR = 2.77; 95% CI = 1.66-4.63), specifically with behavioural and psychotic symptoms. The ApoE epsilon4 allele showed association with the progression to ATD (OR = 1.81; 95% CI = 1.11-2.94). The logistic regression model showed a significant association between the PBS and the epsilon4 allele with the progression to ATD.
Conclusions: The PBS presence in MCI patients is associated with ATD progression with or without ApoE epsilon4 allele.