Cognitive functions in first-episode depression and recurrent depressive disorder.
BACKGROUND
Cognitive deficits in the course of depressive disorders affect mainly memory, attention and the frontal functions. They are associated with both an earlier onset of symptoms and prolonged episodes. The main aim of the study was to verify the hypothesis of differences in the effectiveness of cognitive processes between patients with a first episode of depression (ED-I) and recurrent depressive disorders (rDD).


METHODS
The study comprised 210 subjects: patients with ED-I (n=60) and patients with rDD (n=150). The assessment of cognitive functions was based on performance of the Trail Making Test, the Stroop Test, the Verbal Fluency Test, the California Verbal Learning Test (CVLT) and the digit span from WAIS-R.


RESULTS
There were no statistically significant differences between the analysed groups in the severity of depressive symptoms. The negative impact of depressive symptoms on the effectiveness of cognitive functions was observed. The ED-I group recorded better results compared to the rDD group in terms of the speed of information processing, visual-spatial and auditory-verbal memory and executive functions, auditory-verbal immediate and delayed memory, ability to learn and verbal fluency. The same differences were observed with respect to the patients from the ED-I group and the patients with the second episode of depression (ED-II) in the course of rDD.


CONCLUSIONS
There are significant differences in cognitive functioning of patients with a depressive episode and recurrent depressive disorders. These differences are already visible from the second episode of a major depressive disorder. Memory, verbal fluency and frontal functions are reduced.
Department of Adult Psychiatry, Medical University of Lodz, Aleksandrowska 159, 91-229 Lodz, Poland, talarowskamonika@wp.pl.
Monika
M
Talarowska
Marlena
M
Zajączkowska
Piotr
P
Gałecki
D001288:Attention; D002908:Chronic Disease; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D003866:Depressive Disorder / Q000150:complications / Q000175:diagnosis / Q000523:psychology; D017050:Episode of Care; D056344:Executive Function; D005260:Female; D006801:Humans; D007361:Intelligence Tests; D008297:Male; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012008:Recurrence; D013223:Statistics as Topic; D013647:Task Performance and Analysis