|
Is elderly depression associated with intellectual deterioration?
Eva Dierckx, Sebastiaan Engelborghs, Rudi De Raedt, Karen Maertens, Peter Paul De Deyn, and Ingrid Ponjaert-Kristoffersen
Objective
This study was performed to investigate whether intellectual deterioration (i.e. the difference between actual and premorbid levels of intelligence) is present among older persons with a depressive disorder and among patients suffering from Mild Cognitive Impairment (MCI), and whether it could be a clinical useful concept to differentiate between Alzheimer?s Disease (AD) and depression.
Material and methods
A Dutch version of the National Adult Reading Test (NLV), a measure of premorbid IQ and the Raven Coloured Progressive Matrices (RCPM), a measure of actual intelligence were administered together with the MMSE, and the Geriatric Depression Scale (GDS) to 61 AD patients, 49 depressed elderly, 41 MCI-patients and 61 healthy control subjects. Intellectual deterioration was operationalized by subtracting premorbid intelligence (i.e. standardized NLV scores) from actual intelligence (i.e. standardized RCPM scores).
Results
A t-test revealed that depressed elderly and healthy control subjects did not significantly differ in the degree of intellectual deterioration. Besides this a 1- way ANOVA with post hoc Scheff? showed that only AD patients in the moderate stage (MMSE score between 14 and 19) showed greater intellectual deterioration than depressed elderly. No significant differences were found between mild AD (MMSE score ≥ 20) and depressed patients.
Conclusion
According to our study intellectual deterioration is absent among depressed elderly and MCI-patients. Because the differentiation between mild AD and depression could not be made by means of the difference between NLV and RCPM scores, the clinical utility of the concept of intellectual deterioration for early differential diagnosis remains unproven.
|
- GO BACK - |
