Association Between Depression And Oxidative Stress Levels In Patients On Maintenance Hemodialysis

Objective: To discuss the related factors of depression and the relationship between depression and oxidative stress levels in patients on maintenance hemodialysis(MHD) by investigation of general conditions,detection of biochemical indexes and oxidative stress markers and assessment of depression.Methods: A total of 79 patients(the hemodialysis group) with complete data on maintenance hemodialysis in The First Affiliated Hospital of Soochow University were included in this study between July 1,2009 and December 31,2010; 41 cases with healthy kidneys,no history of mental illness and no other related diseases were selected as the normal control group. The hemodialysis group and the normal control group matched for age and sex.Biochemical and blood indicators, highly sensitive C-reactive protein(hs-CRP),parathyroid hormone and serum ferritin were detected in all included patients. The levels of parathyroid hormone and serum ferritin were determined by chemoluminescence method. Blood samples(2ml) of the patients and the control individuals were taken for measurement of oxidative stress indicators including malondialdehyde(MDA), 8-hydroxy-2'-deoxyguanosine (8–OHdG) and total antioxidant capacity(T-AOC) . The levels of MDA,8-OHdG and T-AOC were respectively determined by colorimetric method, enzyme linked immunosorbent assay(ELISA) and FRAP method.Within 24h after blood collection, Beck Depression Inventory-2nd Edition(BDI-Ⅱ)was used to assess the depression level. According to the BDI-Ⅱscore obtained,patients were divided into three subgroups:non-depression subgroup,mild to moderate depression subgroup and severe depression subgroup.The general data of all the patients were also collected including age,sex,primary disease,hemodialytic time,educational degree,occupation,income and marital status.SPSS11.5 statistical software was used for data analysis to discuss the related factors of depression and the relationship between depression and oxidative stress levels in patients on maintenance hemodialysis.Results:(1). MDA, 8-OHdG and T-AOC significantly increased in the hemodialysis group comparing with those of the normal control group. The differences were significant between the two groups(P<0.01).(2) The incidence of depression in the hemodialysis group was 57%(45/79).The incidence of mild to moderate depression and severe depression were respectively 40.5%(32/79) and 16.5%(13/79). There was no statistical significance in age,sex,hemodialytic time,educational degree,occupation and income among the three subgroups(P>0.05). Statistical significance was observed among the three subgroups with respect to marital status(P<0.05).Severe depression subgroup had the higher proportion of non-spouse than the other two subgroups.(3) Serum albumin(ALB),prealbumin(PAB) were significantly lower in severe depression subgroup compared to the other two subgroups,hs-CRP,MDA and 8-OHdG were significantly higher in severe depression subgroup compared to the other two subgroups(P<0.05). The difference had no statistical significance between non-depression subgroup and mild to moderate depression subgroup with respect to the indexes mentioned above(P>0.05).White blood cell(WBC) was significantly higher in severe depression subgroup compared to non-depression subgroup(P<0.05). There was no statistical significance among non-depression subgroup and mild to moderate depression subgroup, mild to moderate depression subgroup and severe depression subgroup(P>0.05).No statistical significance was observed with respect to T-AOC among the three subgroups(P>0.05).(4) The depression score showed a positive correlation with hs-CRP,WBC and MDA, but a negative correlation with ALB and PAB.(5) Among 7 factors correlated with depression at the univariate analysis , only 2 factors were still strongly correlated with depression at the multinomial logistic regression analysis: MDA and PAB. MDA in severe depression subgroup was 2.39 fold compared to non-depression subgroup.Conclusions: (1) Patients on maintenance hemodialysis had a significantly higher level of depression.(2) There was a state of oxidative stress in patients on maintenance hemodialysis.(3)The occurrence of depression in patients on maintenance hemodialysis correlated with marital status, inflammation,nutrition status and oxidative stress levels.(4) MDA and PAB were independent risk factors for occurrence of depression in patients on maintenance hemodialysis.