Attention Bias And Changes Of Heart Rate Variability During Task In Somatic Symptom Disorder

Objectives:(1)To compare the attention bias and its relationship with symptom severity and psychological characteristics between patients with somatic symptoms disorder and healthy controls(2)To compare the autonomic nerve function and change trend between patients with somatic symptoms disorder and healthy controls during resting period and emotional load.(3)To analyze the relationship between heart rate variability and symptom severity and psychological characteristics.Methods: This study included 33 patients with somatic symptom disorder and 33 healthy controls matched with sex and age.Patient Health Questionnaire-9(PHQ-9),7-items Generalized Anxiety Disorder Scale(GAD-7),Patient Health Questionnaire-15(PHQ-15),Somatic System Disorder-B Criteria Scale(SSD-12)and Health related anxiety scale(WI-8)were selected to evaluate the symptom severity of SSD.Type D Personality Scale(DS-14),Toronto alexithymia scale(TAS-20)and Childhood Trauma scale(CTQ)were used to evaluate the psychological characteristics of SSD.Dot-probe task by E-prime edited was used to evaluate the subjects’ attention bias to emotional stimulation,the differences of attention bias between the two groups were compared,and the correlation between the index of attention bias and the severity of the symptom and psychological characteristics was analyzed.The changes of HRV indexes in resting state and emotional load were compared between the two groups,and the correlation between HRV indexes in each stage and the disease severity and psychological characteristics of SSD was analyzed.Receiver operating characteristic was used to analyse the value of HRV index in the diagnosis of somatic symptom disorder.Results:(1)The reaction time of negative pictures was longer than that of positive pictures(P < 0.05).The scores of negative attention orientation in SSD group were significantly higher than those in HC group by independent sample t-test.The positive disengaging index in SSD was positively correlated with their cognition of the disease.The negative disengaging index in SSD was negatively correlated with emotional neglect(P < 0.05).(2)In resting period,SDNN and LF in SSD group were significantly lower than those in HC group(all P < 0 05).Under the task state,the HRV index of SSD group showed an upward trend,while that of HC group showed a downward trend,except for LF/HF.The reactivity scores of RMSSD and LF in SSD group were significantly higher than those in HC group.The HRV recovery score of PNN50 in SSD group was significantly lower than that in HC group(all P < 0 05).(3)In resting period,RMSSD was negatively correlated with symptom severity(GAD-7,PHQ-9 and behavioral factors of SSD-12)(r=-0.361～-0.404,P<0.05),HF was negatively correlated with symptom severity(GAD-7,PHQ-9)(r=-0.378～-0.365,P<0.05).LF/HF was positively correlated with symptom severity(GAD-7,PHQ-9,the total scores of SSD-12 and the affective and behavioral factors)(r=0.345～0.517,P<0.05).In the HRV reactivity score,SDNN and TP were positively correlated with the total score of SSD-12(r = 0.371,P < 0.05),while LF/HF was negatively correlated with type D personality and its social inhibitory factor(r=-0.404～-0.407,P<0.05).In the HRV recovery score,LF was negatively correlated with PHQ-15(r=-0.347,P=0.048),and LF/HF was negatively correlated with the total score of SSD-12(r=-0.347,P=0.048),SDNN was positively correlated with the social inhibitory factor of type D personality and extroverted thinking of alexithymia(r=0.373～0.395,P<0.05),and positively correlated with extroverted thinking of alexithymia(0.348,0.348,0.047),and positively correlated with extroverted thinking of alexithymia(r=0.373～0.395,P <0.05),and positively correlated with extroverted thinking of alexithymia(r = 0.348,P < 0.047).The clinical value of LF response score in female SSD was significant with AUC=0.691,the sensitivity and specificity were 1 and 0.4respectively.Conclusions:(1)There is autonomic nerve dysfunction in patients with somatic symptom disorder,which can not effectively regulate emotional response.Compared with the resting HRV index,the change of HRV in the task state has more potential for the diagnosis of the disease.(2)SSD have attention bias to negative stimuli,and the attention bias is significantly correlated with negative cognition and childhood emotional neglect.(3)Both autonomic nerve dysfunction and attention bias may be involved in the pathophysiological mechanism of somatic symptom disorders.