Abstract
The relationship of cognitive function to depression in older adults has become a topic of extensive clinical interest and research.
Objective:
To analyze association between cognitive/memory performance, Major Depression, and education in 206 inpatients from the Psychiatry and Internal Medicine Departments.
Methods:
Patients were evaluated by the Mini Mental State Examination, a battery of memory tests, and the MontgomeryÅsberg Depression Rating Scale. Depression patients comprised 45 severe and 42 mild/moderate, according to the Montgomery-Asberg scale. The effect of psychoactive drugs was recorded (30% drug-free). Education was measured in years. Cognitive/memory tests assessed five domains: general mental functioning, attention, sustained attention/working memory, learning memory (verbal), and remote memory. An index for memory impairment was created (positivity: 50% of tests below cutoff).
Results:
The chief effect on worse performance was Major Depression for the domains (age and education adjusted) of attention, learning, remote memory, and general functioning. For the domain "sustained attention and working memory", only severely depressed patients differed from the medical controls (p=.008). Education showed an independent effect on test performances. No interaction between depression and educational status was observed. We also observed an independent effect of psychoactive drugs on some cognitive/ memory domains. Logistic Regression showed Major Depression as the main risk for cognitive impairment.
Conclusions:
These data demonstrated association of Major Depression with impaired cognitive performance independent of educational attainment or psychiatric medications.
Key words:
depression; neuropsychological tests; memory; cognition; education; Brazil.