Abstract
A lack of awareness of deficits or illness (anosognosia) is common in Alzheimer's disease, it can be observed in mild cognitive impairment as well. Our aim is to investigate the correlation between lack of insight and performance on neuropsychological tests as well as frontal and parietal cortical thickness in patients with amnestic Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD). Twenty-one patients with AD and 24 with MCI were included in this study. Insight was assessed using the Clinical Insight Rating Scale (CIR) and discrepancy scores between patients' and caregivers' reports on a 30-item Anosognosia Questionnaire- Dementia(AQ-D). Cognitive functions were examined with a range of neuropsychological tests. MRI was obtained in 37 patients, frontal and parietal cortical thicknesses were measured in each group. The total group (AD+MCI) of patients with “impaired insight” showed poor performance in Digit Ordering test, Digit Span Backwards and Clock Drawing Test compared to patients with “preserved insight”. Anosognosia was significantly correlated with MMSE, Immediate recall, Free Recall after short delay, Free Recall after long delay, Digit Span Backwards and Clock Drawing Test scores in the total group. MCI patients with “impaired insight” showed poor performance in Immediate recall, Digit Ordering Test, Digit Span Backwards and Clock Drawing Test compared to MCI patients with “preserved insight”; anosognosia was significantly correlated with MMSE, Immediate recall, Free Recall (both after short and long delay), Digit Ordering Test and Digit Span Backward scores in the MCI group. No significant differences were found between AD patients with or without insight. Frontal and parietal cortical thickness did not differ significantly between patients with versus without insight in the total, MCI or AD group (p