Characteristics And Risk Factors Of Cognitive Impairment In Young And Middle-aged Patients With Acute Major Depressive Disorders

Objective: 1.To evaluate the characteristics of cognitive function in young and middle-aged patients with acute major depressive disorder(MDD)2.To compare the differences of cognition between MDD patients with first depressive episode and recurrent depressive episode.3.To analyze the influential factors of cognitive impairment in patient with MDD.Methods:650 patients who met the MDD diagnostic criteria of the Diagnostic and Statistical Manual of the Mental illness of fourth edition(DSM-IV)were recruited from psychological clinic in nine centers of China.At the same time,288 age-,gender-and education-matched healthy controls(HC)were enrolled.The demographics information and clinical characteristic of MDD patients were collected through a thorough Questionnaire.The Mini International Neuropsychiatric Interview(M.I.N.I.)served as a diagnostic tool and the Hamilton Rating Scales of Depression-17(HAMD-17)was used to evaluate the severity of depression.All the candidates undergone a full set of cognitive function examination,including the Animal Fluency Test(AFT),the Symbol Digit Modalities Test(SDMT),the Hopkins Word Learning Test-Revised Edition(HVLT-R),the Brief Visuospatial Memory Test-Revised(BVMT-R),and Trail Making Test(TMT)to access the verbal fluency,psychomotor speed,verbal memory,visual space memory,and executive function respectively.We compared the differences in cognitive characteristics between MDD and HC patients.We divided the MDD patients into the FED group and the RDE group on the basis of the number of episodes and then compared the differences in cognitive characteristics between the two groups.MDD patients whose test results decreased more than 1.5 SDs from the mean results of HC were considered to have dysfunction in this cognitive domain.Patients with two or more abnormal domains were considered cognitive impairment;otherwise,were defined as cognitive reserve.Then we compared the differences of cerebrovascular risk factors,the age of first-onset,the number of episodes,the subtype and course of depression,the duration of acute episode,the score of HAMD between the cognitive impaired group and cognitive reserved group to explore the influential factors of cognitive impairment in patients with MDD.Result:1.Compared with the HC group,the AFT,the BACS,the TMT-A,the total recall scores the delayed recall scores of the HVLT and the BVMT were lower(P <0.05),and the TMTA and TMTB test scores are higher in MDD group(P <0.05).2.Among MDD patients,439 patients with first depressive episode and 202 patients with recurrent depression episode were compared the cognitive function,except 9 patients who lacked information.The FDE group and the RDE group had lower scores than the healthy control group in the AFT,BACS,HVLT trial-3,HVLT total learning,HVLT delay recall,BVMT total learning,BVMT delay recall,and TMTA(P<0.05),and higher score in the TMT-B than HC group(P < 0.05).FDE group showed better performance in the HVLT trial 2 and 3,BVMT delayed recall,and the TMT-B than RDE group(P<0.05).3.There were one hundred and sixty-three MDD patients were defined as cognitive impairment and four hundred and eighty-six were defined as cognitive reservation.The Univariate analysis displayed that the two groups differed in the age of first-onset,the number of episodes,the risk factors of cerebrovascular disease and the score of HAMD.Multivariate regression analysis showed that the increased number of episodes were independent risk factors cognitive impairment in MDD patients,while the risk factors of cerebrovascular disease,the age of first-onset and the score of HAMD were not.The risk of cognitive impairment increased by 1.327 times with one more episode of depression(P <0.05,95% CI: 1.024-1.179).The duration of episode,the course and the subtype of depression showed no effects on cognition of young and middle-aged patients with major depressive episode(P>0.05).Conclusion: 1.There were extensive cognitive impairments in MDD patients during the acute phase,including attention,memory,executive function,and language.2.Compared with HC,the FDE and the RDE patients exhibited impairment in all cognitive fields.The RDE patients were worse in the areas of memory and executive function than the FDE patients.3.The decreased age of first-onset and the increased number of episodes are risk factors for cognitive impairment in young and middle-aged MDD patients.The number of episodes are independent risk factors.Patients with more episodes are more likely to suffer from cognitive dysfunction.The duration of episode,the course and the subtype of depression did not contribute to cognitive impairment in young and middle-aged patients with MDD.