Comparison on characteristics of cognitive function in first-episode and recurrent depression

doi:10.3969/j.issn.1009-6574.2016.01.012

Abstract：Objective To investigate the characteristic of cognitive function ,its differences in pa-tients with first -episode and recurrent depression and its correlation with the severity of the disease. Methods We recruited 61 depressive patients met DSM - Ⅳ criteria for depression from Wuxi Mental Health Center.These patients were divided into two groups:first-episode group (n= 31) ,and recur-rent group (n = 30).We also recruited 31 healthy people and assigned them into control group.All the groups were assessed with Wechsler Digit Span(DS) ,Wisconsin Card Sorting Test (WCST ) and Iowa Gambling Task (IGT ).Three groups were compared in the differences of each measurement ,assessed the degree of depression with HAMD-24 and analyzed its correlation with the index of cognitive func-tion.Results (1)Differences in the three groups of patients with DS score were statistically significant (P < 0.05) ,in which the recurrent group was significantly lower than control group (P< 0.05).There were no significant differences between the first -episode and recurrent group ,also the first -episode and control group (P> 0.05).(2)Differences of WCST in the three groups were statistically significant (P < 0.05) ,in which the differences between the recurrent and the control group ,also the recurrent and fires-episode group were statistically significant (P < 0.05).There was no significant difference be-tween the control group and first-episode group in WCST (P> 0.05).(3)The three groups were sig-nificantly different in IGT (P < 0.05) ,in which the indicators in recurrent group were higher than the control group (P< 0.05)except the second module.The total score ,third and fifth module scores of re-current group were higher than first-episode group (P< 0.05).(4)The total HAMD score of depres-sion patiens(first -episode and recurrent group) were negatively correlated with the score of the digit span and the number of classification (r= -0.373 ,-0.299 ;P= 0.003 ,0.019)and were positively cor-related with the number of WCST error response ,sustained response error number ,the number of non-sustained response errors and IGT total score , the third and fifth module score (r = 0.265 -0.461 ,P < 0.05).There was no significant correlation between the first ,second and fourth module of IGT (P >0.05).Conclusions First-episode depression patients don't show obvious impairments in short -term memory and executive function ,In emotional decisional decisions ,they tend to make low income and low -risking decision.The short -term memory and executive function in patients with recurrent depression were significantly compromised and the emotional decision-making for losses are more sensitive than the first-episode patients.Depression level is positively correlated with cognitive impairment ,long disease duration and the severity of depression may have an important impact on patients' cognitive impairment.