A Comparative Study Of Sleep Disorders And Event-related Potential P300 In Patients With Unipolar And Bipolar Depression

BackgroundUnipolar depression and bipolar depression are two common psychiatric disorders with different pathogenesisthat are often associated with cognitive impairment and sleep disorders.They are often misdiagnosed in clinical because of similar early symptoms.This may not be conducive to the patient's early recovery.The research about unipolar and bipolar depression focus on the clinical features,so further study on sleep and cognitive characteristics of unipolar and bipolar depression patients may provide an important theoretical basis on the diagnosis and prognosis of these two disorders.Objectives1.To compare subjective and objective sleep status and cognitive function among unipolar depression patients,bipolar depression patients and healthy control,To understand the characteristics of sleep disorders and cognitive dysfunction in patients with depression.2.To explore the difference of sleep disorders and cognitive dysfunction between unipolar depression patients and bipolar depression patients,to provide evidence for different clinical differential and treatment.Methods1.Objective:Thirty patients with unipolar depression,30 patients with bipolar depression and 30 healthy volunteers matched for gender and age were recruited from Zhumadian psychiatric hospital of Henan Province from August 2016 to August 2017.2.Method:All patients and paticipants completed the following evaluations.We use the Hamilton Anxiety Scale(HAMA)and the Hamilton Depression Scale(HAMD)to assess the severity of anxiety and depression and the Pittsburgh sleep quality index scale(PSQI)to assess subjective sleep;All of them taken overnight polysomnography(PSG)to assess objective sleep;We also use mini mental evaluation state scale(MMSE)and P300 event-related potentials(ERP-P300)to evaluate the cognitive function.3.Statistical analysis:SPSS 17.0 software package was used for statistical analysis.Continuous variables were shown by mean ± standard deviation((?)± S).Comparing among groups were proformed using chi square test for categorical variables,one-way ANOVA and test for.normal distributed data and nonparametric tests for abnormally distributed data.Correlations between parameters was performed by pearson correlation analysis.The difference was statistically significant with P<0.05.Results1 General dataSeven patients refused to continue taken part in the study and were excluded from the study.A total of 83 patients were enrolled in the study,including 27 patients with unipolar depression,26 patients with bipolar depression and 30 healthy volunteers.There was no significant difference in sex,age and vear of education among three groups(P>0.05).There was no significant difference in family history,course of disease and attack times between unipolar depression group and the bipolar depression group(P>O.05).2 Comparison of clinical data2.1 Results of HAMA and HAMD:There were significant differences in total score and factor scores of HAMD among unipolar depression group,biphasic depression group and normal control group(P<0.01).Significant differences were shown in total score of HAMD,anxiety physical factor,cognitive disorder factor,retardation factor and sleep factor among the three groups(P<0.01)while there were no significant difference between unipolar depression group and normal control group in weight factor(P<0.05).We also found significant difference between bipolar depression and unipolar difference in cognitive impairment factor,sleep disturbance factor and total score of HAMD(P<0.01),and the total score of HAMD and score of cognitive impairment and sleep disorder were higher in bipolar depression group.There were significant differences in total score of HAMA and factors scores among unipolar depression group,bipolar depression and normal control group(P<0.01).There were also significant differences between unipolar depression group and normal control group and between bipolar depression group and normal control group(P<0.01).Unipolar depression group and bipolar depression group had significant difference in total score and factor scores of HAMA(P<0.01),and the scores in bipolar depression group were higher than those in unipolar depression group.2.2 Results of PSQI(subjective sleep):Total score of PSQI and factor scores were significant differences among three groups(P<0.05).Compared with normal control group,total score of PSQI and factor scores in unipolar depression group and bipolar depression group were significantly different(P<0.01)respectively.There were nosignificant difference in total score of PSQI and factor scores between unipolar depression group and bipolar depression group(P>0.05).2.3 Results of PSG(objective sleep):Significant difference in sleep efficiency(SE),non-rapid eye movement(NREM1)sleep,slow wave sleep time(SWS),REM sleep latency(REML)and apnea hypopnea index(AHI)among three groups(P<0.05).Compared with normal control group,unipolar depression group showed increased slow wave sleep time(SWS),longer REM sleep latency(REML)and more severe oxygen desaturation index(ODI)(P<0.05)while bipolar depression group showed decreased sleep efficiency(SE),average oxygen saturation(MSa02)and the lowest oxygen saturation(LSa02),increased NREM1 sleep,slow wave sleep(SWS),percentage of SWS,apnea hypopnea index(AHI),oxygen desaturation index(ODI)and the average oxygen ratio(MODD)and longer REM sleep latency(REML)(P<0.05).Compared to unipolar depression group,bipolar depression group had lower sleep efficiency(SE)and shorter REM sleep(REM),increased NREM1 sleep,NREM2 sleep.,SWS and REM sleep latency,higher apnea hypopnea index(AHI)and increased average oxygen ratio(MODD)(P<0.05).2.4 Results of MMSE(subjective cognition):There were significant differences in delayed memory,language,visual space and MMSE total score among unipolar depression bipolar depression and normal compared group(P<0.01).Compared with normal control group,there was significant difference in delayed memory,language,visual space and total MMSE scores in unipolar depression group and bipolar depression group,respectively(P<0.01).There was no significant difference in MMSE total score and factor scores between unipolar depression group and bipolar depression group(P>0.05).2.5 Results of ERP-P300(objective cognition):There were significant difference among unipolar depression group,bipolar depression group and normal control group in P300(P<0.01).Compared with normal control group,there were significant difference in unipolar depression group in P3 latency(P<0.05),N2 latency,N2 amplitude and P3 amplitude(P<0.01);there were significant difference in bipolar depression group in P3 latency(P<0.01)and N2 wave amplitude(P<0.05).Compared with unipolar depression,bipolar depression group showed higher N2 latency and P3 latency and lower N2 amplitude and P3 amplitude(P<0.01).3.Correlation analysis3.1 There was no correlation between N2 latency and scores of all scales.There was a positive correlation between HAMD,HAMA,PSQI and P3 latency(P<0.01),and a negative correlation between MMSE and P3 latency(P<0.01);N2 amplitude was negatively correlated with HAMD,HAMA(P<0.05)and P3 was positively correlated with PSQI(P<0.05).3.2 Sleep latency(SL)was negatively correlated with HAMD,HAMA,PSQI(P<0.05);Apnea hypopnea index(AHI)was positively correlated with HAMD,HAMA(P<0.01),and MMSE was positively correlated with PSQI(P<0.05);Oxygen desaturation index(ODI)was positively correlated with HAMD,HAMA,PSQI and MMSE(P<0.05);The average oxygen ratio(MODD)was positively correlated with HAMD,HAMA and PSQI(P<0.05),and positively correlated with MMSE(P<0.01);The average oxygen saturation(MSaO2)was negatively correlated with HAMD,HAMA(P<0.05);The lowest oxygen saturation(LSaO2)was negatively correlated with HAMD,HAMA(P<0.05).3.3 N2 latency in P300 was positively correlated with total recording time(TRT)in PSG(P<0.05.P3 latency was negatively correlated with rapidy eye movement(REM)sleep and positively correlated with oxygen desaturation index(ODI)(P<0.05).The amplitude of N2 was negatively correlated with total recording time(TRT)(P<0.05).There was a negative correlation between the amplitude of P3 and total recording time(TRT),sleep time(SPT)(P<0.01),total sleep time(TST),non-rapid eye movement sleep(S2)and a positive correlation between the amplitude of P3 and percentage of SWS sleep(SWS%)and oxygen desaturation index(ODI)(P<0.05).Conclusions1.Both unipolar and bipolar depression patients had obvious depression and anxiety symptoms,and bipolar depression patients is more serious than unipolar depression patients;2.Both unipolar and bipolar depression patients had subjective and objective sleep disorders,and bipolar depression patients had more severe objective sleep disorders than unipolar depression patients;3.Both unipolar and bipolar depression patients had obvious cognitive dysfunction,and bipolar depression is more serious than unipolar depression;...