Correlation Among Depressive Symptoms And Quality Of Life In Patients With Major Depressive Disorder:Moderated Mediating Effect

Objectives:To（1）Investigate the status of quality of life（Qo L）of patients with major depression disorder（MDD）and their differences in social demographic characteristics;（2）To examine the mediating role of perceived stress in the relationship between depressive symptoms and Qo L of patients with MDD;（3）To examine the moderating role of self-efficacy in the relationship between perceived stress,depressive symptoms and Qo L of patients with MDD.Methods:Using convenient sampling,patients with major depression disorder who were treated in the psychiatry departments of two general hospitals in Hunan Province from January 2019 to February 2020 were selected as research subjects,and the self-compiled general data questionnaire,Patient Health Questionnaire-9（PHQ-9）,Perceived Stress Scale（PSS）,General Self-Efficacy Scale（GSES）and Form-36 Health Survey questionnaires（SF-36）were used for investigation.The data were entered by double checking,and SPSS23.0 was applied for statistical analysis,including descriptive statistical analysis,single-sample t-test,Pearson correlation analysis,multiple linear regression analysis,and PROCESS macro program for structural equation model testing.Results:1.A total of 423 participants were recruited in this study,and 416valid questionnaires were recovered with an effective rate of 98.3.There were 130 males and 286 females,with an average age of（29.60±11.95）.281patients（67.5%）were recruited in the outpatient clinic and 135 patients（32.5%）in the ward.307 patients（73.8%）lived in urban areas and 109patients（26.2%）lived in rural areas.Meanwhile,less than one-third（29.1%）of the patients were only children,and more than half（54.8%）were unmarried.2.After the conversion of the percentile system,the overall Qo L score of MDD patients was（40.93±9.71）,of which the physical health score was（41.18±11.51）,and the mental health score was（40.59±13.25）.The score is higher than the domestic norm,and the difference is statistically significant（physical health score:t=-135.71,P<0.001;mental health score:t=-115.31,P<0.001）.3.The depressive symptoms score of MDD patients was（16.64±6.28）,which higher than the cut-off point of depression;the perceived stress score was（37.12±6.05）;the self-efficacy score was（19.74±5.84）.The score is higher than the domestic norm,and the difference is statistically significant（perceived stress score:t=47.58,P<0.001;self-efficacy:male,t=-19.11,P<0.001;female,t=-13.95,P<0.001）.4.Pearson correlation analysis showed that Qo L was significantly negatively correlated with depressive symptoms,perceived stress（r₁=-0.33,P<0.001;r₂=-0.19,P<0.001）,while significantly positively correlated with self-efficacy（r=-0.12,P<0.05）.5.Multiple linear regressions showing marriage,disease duration,depressive symptoms and perceived stress into the regression equation for Qo L（R²=0.17,Adj.R²=0.14,F=5.97,P<0.001）.6.Path analysis showed that stress perception had a partial mediating effect between depressive symptoms and Qo L.The mediating effect was-0.03（SE=0.01）,and the 95%confidence interval was（-0.06,-0.01）.7.The interaction item of self-efficacy and depressive symptoms has a significant predictive effect on Qo L[β=0.21,P<0.001,95%CI=（0.10,0.31）];the interaction item of perceived stress and depressive symptoms has a significant predictive effect on Qo L[β=0.20,P<0.001,95%CI=（0.11,0.31）].Conclusion:1.The Qo L of patients with MDD is poor,in which the quality of physiological functioning is relatively higher,while the quality of emotional functioning is relatively lower;the self-efficacy of MDD patients is at a low level compared with healthy groups;their perceived stress is also higher than the health population.2.There is a significant correlation between depressive symptoms,perceived stress,self-efficacy and Qo L in patients with MDD.Depressive symptoms and perceived stress were negatively correlated with Qo L,while self-efficacy was positively correlated with Qo L.3.In socio-demographic data,marital status and disease course of depression patients have significant predictive effects on patients’Qo L.Compared with the patients with married,patients with unmarried have a lower level of Qo L.Patients with a course of 1～5 years had the worst quality of life.The QoL of non-only-child patients was higher than that of only-child depression patients.4.Perceived stress has a partial mediating effect between depressive symptoms and Qo L,and depressive symptoms may increase the perceived stress in patients with MDD.Self-efficacy has a significant moderating effect on the relationship between perceived stress and Qo L,and depressive symptoms and QoL.