Prediction of the prognosis of somatoform disorders using the Minnesota 1 Multiphasic Personality Inventory (MMPI)

1 Background: To elucidate the possibility of using the Minnesota Multifaceted 2 Personality Inventory (MMPI) to predict the prognosis of somatoform disorders, which 3 are often treatment-resistant, we investigated the prognosis of somatoform disorders 4 predicted using the MMPI. 5 Methods: During the period from January 1, 2013, to December 31, 2017, 125 cases of 6 somatoform disorder were diagnosed in the psychiatric department of Fukushima 7 Medical University Hospital, among which, 67 were consultation-liaison psychiatry 8 cases and 58 cases were only psychiatric cases. Clinical information, MMPI scores, and 9 prognosis information were collected from medical records in each case, and then 10 statistical analysis was performed. 11 Results: The results showed that the unchanged group had significantly higher scores 12 than the improved group on only the Hy scale. Receiver operating characteristic 13 analysis of the Hy scale scores of the improved and unchanged group was then 14 conducted to calculated a cutoff value. The cutoff point was 73.5 with a sensitivity of 15 0.557 and a specificity of 0.717. 16 Conclusion: For patients diagnosed with somatoform disorder who had an MMPI Hy 17 scale score higher than the cutoff value, improvement with conventional supportive psychotherapy or drug therapy was predicted to be difficult. Therefore, the cutoff point 1 identified in this study appears to be an important index for selecting treatment for 2 somatoform disorders.

statistical analysis was performed.

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Results: The results showed that the unchanged group had significantly higher scores  Conclusion: For patients diagnosed with somatoform disorder who had an MMPI Hy 17 scale score higher than the cutoff value, improvement with conventional supportive 18 5 psychotherapy or drug therapy was predicted to be difficult. Therefore, the cutoff point 1 identified in this study appears to be an important index for selecting treatment for 2 somatoform disorders. 3 4 Keywords: 5 Hy score 6 consultation-liaison psychiatry 7 Minnesota Multifaceted Personality Inventory (MMPI) 8 Prognostic predictor 9 Somatoform disorders  Statistical Manual of Mental Disorders, fourth edition, text revision (DSM-IV-TR) [2,3]. 5 Chronic pain is classified into nociceptive pain, neuropathic pain, and psychogenic pain 6 [4]. Among these types, psychogenic pain is classified as persistent somatoform pain 7 disorder among the somatoform disorders in the ICD-10, and as chronic pain disorder in 8 the DSM-IV-TR [5]. In addition to the distress of experiencing the symptoms 9 themselves, chronic pain is likely to cause secondary disorders such as psychiatric 10 problems and a decreased ability to carry out activities of daily living. Therefore, 11 chronic pain is a serious disorder that cannot be overlooked, especially economically, as 12 it can lead to labor loss in the productive population and increased medical expenses 13 because of repeated medical examinations and long-term treatment [6].
14 As pharmacotherapy, selective serotonin reuptake inhibitors (SSRIs),antipsychotic 15 drugs, and benzodiazepine anxiolytics have been considerd to be useful to some extent 16 for somatoform disorders [7]. However, although research elucidating the neural basis of 17 somatoform disorders is currently in progress, no effective treatment has been 18 established. Therefore, recovery from somatoform disorders is often difficult and 1 largely dependent on psychosocial treatment [8]. 2 Since 1996, consultation-liaison psychiatry services, which consist of medical teams 3 including orthopedists, psychiatrists, and other co-medical staffs such as nurses, 4 physical therapists, clinical psychologists, clinical pharmacists, and social workers, have 5 been conducted in Fukushima Medical University Hospital(FMUH). These conferences 6 are held once a month and involve discussions on how to deal with the psychosomatic 7 problems of patients diagnosed with somatoform disorder. Owing to these conferences, 8 we have accumulated substantial MMPI data for these cases. It has been considered that 9 many patients who have psychosocial personality problems or psychiatric disorders 10 have previously consulted an orthopedist because of chronic pain and numbness or have 11 not been satisfied with conventional orthopedic treatment [5,9]. The multidisciplinary 12 nature of this conference is based on recognition that "team medical care," in which 13 related medical staffs cooperate and provide patient-centered medical care, is essential 14 to promote effective treatment and solve various problems. This liaison psychiatry 15 approach is characterized by a basic policy of the orthopedist remaining involved in 16 treatment because even if the patient has psychiatric, psychological, or social problems, 17 the chief complaint is a physical symptom [5,9].

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Numerous studies have reported personality tendencies in patients with somatoform 1 disorders based on the MMPI [10][11][12][13][14][15][16][17][18]. However, to our knowledge, no studies have 2 assessed the utility of the MMPI as an prognostic predictor of somatoform disorders, 3 and only a few reports have used it to predict outcomes of surgical treatment for chronic 4 back pain [19][20][21][22]. In FMUH, the MMPI has been continuously conducted, and data  Although the MMPI has mainly been used for diagnosis and assessment, if it could 10 be used for the prediction of prognosis of somatoform disorders, treatment would be 11 expected to proceed more smoothly because more effective interventions could be 12 started at an early stage, and the patient could recognize the therapeutic effects sooner.

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In addition, considering that MMPI takes quite much time to be completed due to a 14 large number of question items, over 500, if key items predicting negative outcome 15 could be identified, it should be more useful and reduce psychological burden of target 16 patients. 17 The present study has two purposes; one is to clarify psychological and biological 18 factors associating with negative outcome of somatoform disorders, another is to 1 identify key items of MMPI predicting negative outcome. Therefore, we collected the 2 data from patients who all had received MMPI in clinical settings, classified them into 3 two groups (improvedgroup vs. unchanged group) based on the chart review, and 4 examined two groups.  was named "improved group (IG)" and others named "non-improved group (NIG)". 5 We profiled four validity scales (?, L, F, K; interpretation of the conversion V pattern is shown in Table 3. Decreased cerebral blood 8 flow was defined as when a radiologist reported that "there was low blood flow(Vd less 9 than 30ml/ml by ARG method)" based on N-isopropyl-( 123 I)p-iodoamphetamine 10 computed tomography, regardless of the brain region. The comorbidity of 11 developmental disorders was defined as when a psychiatrist noted autism spectrum  Statistical analysis 17 We descriptively compared each factor between the IG and NIG groups. Differences 18 between groups were analyzed using the Mann-Whitney U test, the Student t-test, and 1 the chi-squared test. Among the MMPI scales, receiver operating characteristic (ROC) 2 curves that showed a significant difference between the IG and NIG were created for the 3 Hy scale. The area under the curve (AUC) and 95% confidence intervals (CIs) were 4 calculated, as was the cutoff value using Youden's index. Statistical analysis was 5 performed using SPSS ver. 26 (SPSS, Chicago, IL, USA), and p values < 0.05 were 6 considered statistically significant.

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Prognosticcomparison of the participants' basic characteristics (Table 4) 13 No significant differences in age, gender, duration of illness, the comorbidity of 14 developmental disorders, decreased cerebral blood flow, or history of surgery were 15 observed between the IGand NIG. The mean age ± SD of the IG and NIG were 49.3 ±     The MMPI can identify the personality of subjects from multiple aspects based on 10 answers to questions assessing, for example, hypochondriac, obsessive, and compulsive 11 tendencies. A configuration in which the Hypochondriasis (Hs) and Hysteria (Hy) scale 12 are T = 70 or more and the T score of these two scales is 10 or higher than that of the 13 Depression (D) scale is called the "conversion V" pattern. The conversion V pattern 14 suggests that subjects tend to "replace" their psychological problems with socially 15 acceptable ones, such as physical complaints. Tendencies to escape from a situation 16 through physical complaints, to try and control others, and to suppress or deny the 17 problem are then presumed [9,10]. 18 Then, We carefully discuss each result in detail as follows. Comparison between the improved and unimproved prognosis groups 3 We selected basic characteristics such as age, gender, duration of illness, the 4 comorbidity of developmental disorders, decreased cerebral blood flow, history of 5 surgery, and the conversion V pattern on the MMPI as factors that may affect the 6 outcomeof somatoform disorders. An analysis of each outcome group did not reveal any 7 significant differences. Regarding the cerebral blood flow, it has been reported to be 8 decreased in patients with chronic pain [29]. But no significant differences were found in 9 this study. But the NIG was more likely to have developmental disorders. It has been 10 reported that among developmental disorders in children, both ASD and ADHD are 11 associated with a high rate of chronic pain [30,31]. For ASD and ADHD, it is said that a 12 therapeutic effect can be obtained by combining psychosocial treatment in addition to 13 pharmacotherapy [32,33]. Therefore, when the comorbidity of developmental disorders 14 is recognized, it is thought that somatoform disorders could be improved by performing 15 a therapeutic intervention particularly for developmental disorders. In addition, 16 analysis of each scale of the MMPI showed that only the Hy scale had a significant 17 difference, indicating that the NIG had higher scores on the Hy scale than the improved 18 group. We discuss about what this result mean in detail as follows.

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Significance of high scores on the Hy scale 2 A high score on the Hy scale indicates a tendency to avoid responsibilities related to 3 psychological conflicts by converting these to physical symptoms (a tendency to use 4 conversion symptoms). It also means that individuals with a high Hy score tend to be 5 immature and lack self-insight, indicating that their relationships with other people are 6 often superficial, even though they may appear to be appear to be socially well adopted 7 [9]. A significant difference was observed between the IGand NIG only in this Hy scale 8 score. Therefore, ROC analysis was performed on the Hy score for the IG and NIG, The cutoff point calculated in this study was 73.5, which was even higher than the 2 score generally considered to be abnormal (70). If the Hy scale score of a patient 3 diagnosed with a somatoform disorder is higher than this cutoff value, he or she is 4 considered difficult to treat with conventional supportive psychotherapy or 5 pharmacotherapy. In such cases, it may be necessary to consider psychiatric 6 "multidisciplinary" treatment, which is a further enhancement of conventional  Therefore, this cutoff point appears to be an important index for treatment selection in 10 patients with somatoform disorder. However, since this was a retrospective study, if the 11 Hy scale score exceeds the cutoff point, prospective studies are needed to compare the 12 prognoses of the following two groups: one that is provided with therapeutic 13 interventions such as augmented pharmacotherapy and psychotherapy, psychosocial 14 treatment, and environmental adjustments, and another that receives standard therapy 15 (general pharmacotherapy and supportive psychotherapy). The classification of the outcome of somatoform disorder among the current group 1 used in this study was based on only the chart review not more reliable ways such as 2 diagnostic (structured) interviews or self-administered questionnaires.     Funding : This research did not receive any specific grant from funding agencies in the 8 public, commercial, or not-for-profit sectors. 9 10 Authors' contributions：AS conceived the study.AS and KH collected the data.AS 11 and TK analyzed the data. All authors contributed to data analysis, drafting and 12 critically revising the paper, gave final approval of the version to be published, and 13 agreed to be accountable for all aspects of the work.