Psycho-behavioral Features Of Somatic Symptoms Disorder Patients

Objective:Our study aimed to explore the frequency of DSM-5 Somat-ic Symptoms Disorder(SSD)in Chinese tertiary general hospital outpa-tients,and describe the clinical characteristics of SSD patients,in-cluding the somatic symptoms severity,the psychosocial stress,and the quality of life,and explore the predictors of health related life quality.We expected to validate the Somatic Symptoms Disorder B-criteria Scale(SSD-12)in Chinese tertiary general hospital outpa-tients from three medical settings,providing psychometrics tool for evaluating SSD.Method:Patients were recruited at the department of gastroenterol-ogy,traditional Chinese medicine(TCM)and psychology,Peking Union Medical College Hospital.The MINI-International Neuropsychiatric Interview(M.I.N.I)and Structured Clinical Interview for DSM-V research version(SCID-V-RV)were employed to ensure the somatoform disorder di-agnosis of ICD-10 and the somatic symptoms disorder diagnosis of DSM-V respectively.Patient Health Questionnaire-15(PHQ-15)and Somatic Symptom Scale(SSS-8)were used for the severity of somatic symptoms,Patient Health Questionnaire-9(PHQ-9)for depression,General Anxiety Disorder-7(GAD-7)for anxiety,Whiteley-8 for health-related anxiety(WI-8),Somatic Symptoms Disorder B-criteria(SSD-12)for the psychological criteria of SSD,WHO-DAS for disability assessment,and SF-12 for quality of life.Results:1)We recruited 50 patients from each department,in which 22.0%patients fulfilled the diagnosis of SSD and 50.7%fulfilled the diagnosis of SFD,and the agreement of the diagnoses was poor(cohen k score=0.217,p=0.001).2)SSD patients had higher scores of PHQ-15,SSS-8,PHQ-9,GAD-7,WI?8,SSD-12 and WHO-DAS,more visit times with lower satisfactory degree and poorer subjective effect,and lower scores of PCS and MCS than the patients who only fulfilled SFD diagnosis and the patients who ful-filled neither of the two diagnoses;No significant difference of psy-chological features and life quality was found in SSD patients between 3 department.3)PHQ-9 scores was an independent risk factor of disability,56.4%of total variance can be explained by this equa-tion(F=30.842,p=0.001,VIF<3.5);The score of SSD-12,SSS-8 and treatment in the past 6 months were significant risk factor of PCS,50.1%of total variance can be explained by this equa-tion(F=23.948,p=0.001,VIF<3.5);Marriage,scores of PHQ-9 and GAD-7,and times for seeing a doctor in the past 12 months were independent risk factors for MCS,and 65.5%of total variance can be explained by the equation.The variance of R square when SSD-12 was included into 3 equations was more than that of PHQ-15.4)The reliability of SSD-12 was good in our study(Cronbach?=0.953).Confirmatory factor analysis suggested the 3-factor model of SSD-12 reflected cognitive,affective,and behavioral aspects of B cri-teria of SSD,the model fit was reluctant(n=150,CFI=0.990,TLI=0.987,REMSEA=0.094,90%CI=0.072-0.116),and the correlations between 3 poten-tial variances were high;The general factor model was acceptable(n=150,CFI=0.989,TLI=0.987,REMSEA=0.094,90%CI=0.072-0.115).Total score of SSD-12 can reflect general psychological disturbance,and sig-nificantly associated with the severity of somatic symptoms(r=0.520 for PHQ-15 and r=0.596 for SSS-8),health related anxiety(WI-8,r=0.781),anxiety(GAD-7,r=0.605)and depression(PHQ-9,r=0.658),and the divergent validity was not good.The optimal cut-off value for de-tecting SSD was 17 in our sample when SCID-5 was gold standard diagno-sis of SSD(Youden Index=0.595,sensitivity=0.757,specificity=0.838),with 82%patients can be diagnosed correctly.Conclusion:1.The frequency of SSD was 22.0%in the patients of general hospital outpatient of psychology,gastroenterology,TCM.2.The SSD patients suffered from more severe somatic symptoms,higher level of depression,anxiety and health related anxiety,more visit times with poorer subjective experience,poorer physical health and mental health with higher degree of disability.3.The reliability of SSD-12 was good.The 3-factor model was accepta-ble,but the correlations between 3 factors were high.The total score can reflect the severity of symptom burden and predict the life quality of patients;The optimal cut-off point of SSD-12 to detect SSD was 17.4.The depression severity was an independent risk factor of functional impairment;Total score of SSD-12,somatic symptom severity in last week,treatment in the past 6 months,anxiety,depression and time for seeing a doctor were independent risk factors of poor health related life quality.As somatic symptoms do not have much to do with the health-related life quality and disability,clinical intervention should be focused on the distress caused by symptoms,cognitive distor-tions about symptoms and reducing visit times,instead of eliminating the symptoms.