FULL TEXT (日本語-抄録のみ)
Dissociation and Child Abuse Histories in an Eating Disorder Cohort in Japan
Acta Psychiatrica Scand, 90:274-280; 1994.
1, Tokyo University Department of Psychosomatic Medicine, Tokyo, Japan, Department of Psychiatry, 2, Albert Einstein College of Medicine, Bronx, New York, U.S.A., 3, Keio University Department of Psychiatry, Tokyo, Japan, 4, Tokyo Institute of Psychiatry, Tokyo, Japan.
Presented in part at the Japanese Stress Science Conference, Tokyo, Japan, December 1992. Supported through the National Institutes of Health Foreign Funded Research Program, Bethesda, Maryland U.S.A., by the Japanese Society For The Promotion of Science, Tokyo Japan.
Dissociation and childhood abuse were studied in female eating disorder outpatients in Japan. A self-report version of the Dissociative Disorders Interview Schedule (DDIS),which includes data on physical and sexual abuse, and the Dissociative Experiences Scale (DES) were used. Nine of forty-one subjects who completed the DDIS reported symptoms suggesting DSM-III R multiple personality, and six of the thirty-nine subjects who completed the DES scored over thirty (reflecting a high likelihood of post traumatic stress or multiple personality). Subjects' sexual abuse history rates were considerably greater than those in the Japanese general population. Though physical abuse history was associated with high dissociation, no difference between the high and low dissociators in sexual abuse histories was seen.
Outside of North America there is considerable skepticism about the validity of the dissociative disorders, especially multiple personality disorder (MPD), whose existence is felt to be strongly influenced by culture (1,2). As defined by DSM- III R (3), dissociative disorders are those in which there is a disturbance or alteration in the integrative functions of identity, memory, or consciousness. These include Psychogenic Fugue, Psychogenic Amnesia, Depersonalzation Disorder, and MPD. The distinctive feature of MPD is the existence of two or more personalities or personality states within the individual (3).
The large majority of the literature on dissociation comes from North America (3-9) where the APA created a new diagnostic category, the dissociative disorders, in 1980 (MPD is slated to be called "Dissociative Identity Disorder" in the DSM IV) (10). Additionally, the British literature has suggested that MPD may be culturally specific to North America (11). Although recent reports have found evidence of MPD in the Netherlands (5,12), as well as in Switzerland (13), a study by Takahashi looking at the diagnoses given over a five year period in 489 Japanese psychiatric inpatients did not find one case of MPD, and only seven cases of dissociative disorder (5 with psychogenic fugue and 2 with psychogenic amnesia)(1). This compares with data in North America that suggests 20% of psychiatric inpatients may have a dissociative disorder, 5% of that group having MPD (14).
The Takahashi's study noted the infrequency of the diagnosis of MPD in India (15), and concluded that the strong family bond in Japan (divorce rate about one third that of the U.S.), the high value put on children, and the low incidence of child abuse there (about 6.6 per 100,000 children under the age of 12), might explain the lack of MPD diagnosed in the sample. This study was criticized for it's failure to use structured diagnostic instruments, the inability to control for skeptical bias, and the failure to report the incidence of childhood abuse in the sample (2,16,17). Very few prior case reports of MPD had been in the Japanese literature (18,19), and these were met with much skepticism in Japan.
The present study was a preliminary attempt to more systematically study the occurance of dissociative and MPD symptoms in Japan. This study used structured instruments already well studied in North America, employed a bicultural team of research psychiatrists, and included an analysis of the relationship with child abuse.
Because of the difficulty studying groups of child abuse victims in Japan (they are often secretive and unwilling to participate in research), we looked at a group of eating disorders (ED) who might be likely to exhibit dissociation. Both ED and MPD have been shown to have an association with childhood physical/sexual abuse (4-6,12,20-23), dissociation has been correlated with eating disorders (8,12,24-28), and both ED and MPD are much more frequent in females(3,6,7).
Forty-four Japanese female patients attending an eating disorder out-patient group at the Tokyo Institute of Psychiatry Research Center participated in this study. Participation was voluntary and no renumeration was given. Thirty-five of the patients had bulimia nervosa (eighteen of these had prior histories of anorexia nervosa), one anorexia nervosa, and eight both anorexia and bulimia. None of the patients had evidence of psychosis, active mood disorder, organic brain syndrome or mental retardation, and none had a history of substance abuse.
The mean age of the patients was 24.2 years (range=17-37). 11 of the patients were married or living with a mate, one divorced, and 32 single. 15 were students, 15 were employed, and 14 were unemployed. The average number of school years completed was 13.6 years.
The Dissociative Experiences Scale (DES) is a 28-item visual-analog (possible scores of 0-100) self-report rating scale, that has a test-retest reliability of 0.84 and good clinical validity (29). It is a screening instrument for dissociative disorders, does not make diagnoses, and takes about ten-minutes to complete. Scores above 30 are correlated with a high likelihood of MPD or post traumatic stress (30). The DES is able to discriminate patients with MPD from other diagnostic groups and normal controls (29,31).
Tanabe et al. recently administered this scale to 445 Japanese university students and found that 28.1% of the subjects scored over 30, with an overall mean of 19.5 (32). A North American study of the general population found mean scores of 15.2 (men) and 15.6 (women) for the 18-29 age group, with declining scores as the subjects age , 5% scoring over 30 over all age groups (30). While both studies concluded that dissociative symptoms are common it should be noted that the Japanese study only included college students whose young age may have contributed to the 28.1% DES scorers over 30. Based on the North American data, this percent would be expected to drop as the cohort ages.What proportion of this group actually represents those with dissociative disorder vs. normative "adolescent" data was not investigated, and the North American data did not report what percent scored over 30 in an 18-22 year old group so this can not be compared.
Though the DES has not been validated with a clinical sample of dissociative disorders in Japan, Tanabe reported that DES scores were significantly different in a subgroup of students (N=12) whose frequent dissociative episodes were confirmed by interview compared with another group (N=23) without dissociative episodes and concluded that this supports the validity of the DES in a normal Japanese population (32).
The Dissociative Disorders Interview Schedule (DDIS) is a 131-item structured interview that makes DSM III-R diagnoses of all the dissociative disorders, somatization disorder, major depression and borderline personality (9). It also inquires about a history of substance abuse, child physical and sexual abuse, trance states, schizophrenic symptoms and secondary features of MPD. The DDIS has an overall interrater reliability of 0.68 for the diagnosis of MPD, with a specificity of 100% and a sensitivity of 90%. There is no overall score, results are compared with norms established for MPD in North America. We are not aware of any prior use of the DDIS in Japan.
The DDIS used in this study was modified into a self report questionnaire because Japanese subjects often do not respond directly about sensitive issues in interviews. Additionally, somatic symptoms, psychiatric/substance abuse history, and depressive symptoms were omitted as these areas were covered by clinical reports. The DES, was used in its intended form. Both scales were translated into Japanese; these translations were checked by bilingual Psychiatrists. The DES version was translated anew and may differ slightly from the version used by Tanabe et al.
We had previously reported on a Japanese case with MPD symptoms who was given the DES and modified DDIS (33). Because the dissociative symptoms in this case as well as other cases in our experience in Japan were accurately reflected by these instruments, and because of the need to avoid direct questioning about sensitive issues in this population, we feel the preliminary use of the modified self-report DDIS is appropriate.
Subjects signed informed consent and were given the questionnaires to take home for completion. The primary treating clinicians both handed out, as well as collected completed questionnaires. Subjects were informed that this was a study of looking at various psychologic experiences as well as histories of child abuse. Physical and sexual abuse data was collected via section VII of the DDIS (9). No mention of a purpose to study multiple personality was made. Confidentiality was ensured. Any subject who filled the three DSM-III R MPD criteria were interviewed to confirm that the subject understood the questions and answered correctly.
(Note: Tables not available on-line)
Forty-one subjects completed the DDIS section for MPD diagnostic criteria. Nine (22%) filled the three criteria necessary to make a DSM III-R diagnosis of MPD. Only one subject filled all five NIMH criteria. Twenty six (63.4) recorded a score of zero in this category.
The subjects who filled three or more MPD diagnostic criteria (DDIS MPD+ group), N=9, m=3.33, SD=0.71, were compared with those filling less than three (non-MPD group), N=32, m=0.25, SD=0.57, on multiple variables. Associated with the DDIS MPD+ group (Table 1) included an earlier age of onset of anorexia, increased Schneiderian symptomatology, more MPD associated features (includes amnesia-related experiences, flashbacks, voices, derealization, fugue, etc.), higher DES scores, and more subjects were positive for psychogenic amnesia, and fugue.
The DDIS MPD+ group versus the non-MPD group did not differ on any of the areas of: age, eating disorder diagnosis, age of onset of bulimia, height, weight, educational level, social class (34), parental loss, marital status, history of school absenteeism, kleptomania, antisocial features, suicidal ideas/attempts, self mutilation, drug/alcohol abuse, use of psychiatric or medical services, physical and/or sexual abuse histories, domestic violence, Supernatural/Possession/ ESP/ Cult Experiences (supernatural experiences include questions about ghosts, spirits, telekinesis, clairvoyance, telepathy, deja vu, etc.).
Thirty-nine subjects completed the DES (m=13.56, SD=14.68, range=0-61.1). Because it has been reported that scores above 30 indicate a high likelihood of MPD or post traumatic stress (30), we compared the subjects who scored above thirty (N=6, m=43.6, SD=10.4) to those below thirty (N=33, m=8.1, SD=6.3) on multiple variables. Variables associated with the greater than 30 group compared to the less than 30 group (Table 2) included: greater Schneiderian symptomatology, more MPD associated features, higher scores on borderline pathology, greater total NIMH MPD criteria, histories of physical abuse, more psychogenic fugue, more depersonalization, and higher scores on the Supernatural/Possession/ESP/Cult experiences section.
The greater than 30 and less than 30 DES score groups did not differ in any of the areas of: height, weight, eating disorder diagnosis, age of onset of anorexia or bulimia, educational level, social class, parental loss, marital status, domestic violence, school absenteeism, kleptomania, antisocial features, suicidal ideas/attempts, self mutilation, use of psychiatric or medical services, sleepwalking, trances, imagimnary playmates, psychogenic amnesia, or histories of sexual abuse.
For the eating disorder sample as a whole (N=44), the combined physical and sexual abuse rate was 45.5%, for physical abuse alone 25.0%, and for sexual abuse alone 36.3%.
As can be seen from Table 1 and Table 2, while the DDIS MPD+ group had greater DES scores compared to the non-MPD group, and the greater than 30 Des scorers had more MPD criteria than the less than 30 DES scorers, there was overlap in that not all of the DDIS MPD+ group scored greater than 30 on the DES, and not all the greater than 30 DES scorers filled the three necessary criteria for MPD. Only three subjects (of N=36) scored both over 30 DES and filled MPD criteria.
Of the forty-four subjects, thirteen (29.5%, m=6.2, SD=1.1) filled the five DSM III-R necessary criteria for borderline personality disorder (BPD), while thirty-one did not (70.5%, m=2.0, SD=1.4). Neither physical nor sexual abuse differed in our BPD vs. non-BPD group. The BPD group differed from the non-BPD group (Table 3) in having greater schneiderian symptoms, more MPD associated features, more MPD NIMH criteria (though the BPD group mean of 1.8 was well below the three necessary for the diagnosis of MPD), and greater DES scores. There was a trend for more of the BPD patients to have more MPD associated features though this did not reach significance. There were no differences in any of the other variables tested.
These findings provide the first data on evidence for significant dissociative symptomatology and the existence of MPD-like symptomatology in a psychiatric population in Japan. The limitations of this study included a small N, cultural considerations in the interpretations of questions, and possibly self-reporting. Even though the self-reporting format was a modification, this may have actually strengthened the reliability of our data due to the privacy afforded, though this preliminary study was not designed to answer this question.
Data was gathered by reliable instruments, and the patients who filled DSM III-R MPD criteria reflected the pattern of data obtained by Ross et al. (9) from MPD subjects in North America. Although the patient populations differed (ours were attending a eating disorders clinic, while those in the study by Ross et al. a dissociative disorders clinic), in both studies the patients had high scores in (our study DDIS MPD+ N=9 vs. mean of 102 North American MPD cases): Schneiderian first-rank symptoms, 6.6 vs. 6.4; MPD associated features, 7.2 vs 10.2; and BPD criteria, 4.4 vs. 5.2. This pattern distinguished MPD from other diagnostic groups in North America (35). Additionally, psychogenic amnesia and high DES scores were found in our DDIS MPD+ cases, consistent with the North American data.
Our DDIS MPD+ patients also had an earlier age of onset of anorexia which may reflect a subset of patients in whom dissociation and anorexia are related. While nine of our eating disorder patients filled the three DSM III-R diagnostic criteria for MPD, we suspect (though did not verify) this number may be high for actual MPD and probably reflects significant dissociative pathology, or atypical MPD (ie. transient symptoms), rather than the strict diagnosis of MPD in many of our cases. While the effects of a relatively young age of our cohort should also be considered as a possible contributing factor to increased dissociation (30), good construct validity for the dissociative disorders has been demonstrated in children and adolescents (36).
The DDIS findings were also confirmed by the DES scale scores of our cohort. Our DDIS MPD+ patients' mean DES score of 26.8 reflects the high scores obtained in North American MPD and posttraumatic stress disorder patients compared with other diagnostic groups (9,29,31). Our eating disorder overall mean DES score of 13.56 was similar to the score of 19.5 in 445 Japanese college students (32), as well as the score of 15.6 found in 609 women in the18-29 age range in the general population (30).
While the DES data suggests that dissociative symptoms are not specific to eating disorders, our nine patients (22%) who were DDIS MPD+ indicate that a subset of eating disorder patients have a relationship with high levels of dissociation and that this group requires special attention to the effects of dissociation on psychopathology and treatment. This is consistent with studies in America and Europe which had found a relationship between eating disorders and dissociation (8,12,24-28).
The DES data in Japan support the idea that dissociation is a continuous process ranging from normal phenomena to serious pathology (28) and helps to validate the use of the DES in clinical samples in Japan. At what point do dissociative experiences become pathological? This question was posed by Ross et al. (30) who posited that while a definitive study requires coadministration of the DES and a diagnostic interview to a random sample of the general population, clinical studies using the DES (14) suggest that dissociative disorders may be relatively common, in the range of 5%-10% of the general population.
The fact that only three subjects had scores >30 on the DES and were also DDIS MPD+ can be interpreted in different ways. Our DDIS MPD+ subjects may not necessarily meet strict DSM-III R MPD criteria if they only have transient symptoms, and thus their DES scores could be lower. Some with high DES scores may have other dissociative disorders not in the MPD spectrum (ie. psychogenic fugue/amnesia). While there could be other explanations, for example problems with the validity of these instruments, cultural/language difficulties with the instruments etc., the fact that 3 of 6 (50%) of the >30 DES scorers were DDIS MPD+, and that the 26.8 DES score of the DDIS MPD+ group was significantly greater than the 10.1 DES score of the non-MPD group supports the validity of these assessment procedures consistent with that the North American studies. The DES score of 30 as a cut-off point, however, may need to be reconsidered depending on the population studied.
The other variables listed in Table 2 that were associated with the over 30 DES scores is also consistent with the North American data. We noted that while physical abuse had an association with high DES scores, sexual abuse did not, and neither physical nor sexual abuse was associated with our DDIS MPD+ subjects. While these results will have to be replicated in a larger group of Japanese subjects with dissociative disorders, this seems at odds with the western data. Four large western studies all found between 75%-90% of MPD subjects positive for either sexual or physical abuse( 12,37-39 ). False negative results due to small sample size could have been responsible for this, as well as for the of the lack of association of abuse with BPD in our study. The association of physical abuse and high DES scores in our study, however, supports the hypothesis of childhood trauma leading to dissociation.
The 36.3% of sexual abuse reported in our eating disorder subjects indicates that an overall lack of reported sexual abuse was not responsible for our finding of no relationship of sexual abuse and dissociation. This value is considerably greater than the official Japanese statistic of 0.0066% for child abuse, including sexual abuse, in the general population(1), and may reflect an association between eating disorders and sexual abuse in Japan, and/or a low bias in the Japanese general population statistics. It could be that the Japanese subjects' interpretations of these questions (sexual abuse has not become a topic widely discussed in Japanese society as in the west ) led more of our subjects to consider past minor sexual encounters as "abuse", obscuring any relationship with sexual abuse that the high dissociators may have had, and making our data difficult to compare with official statistics. Another potential problem is that of recall bias, ie., the questionable reliability of adult reports of childhood abuse without corroboration (40).
We also found a considerable overlap of the diagnosis of BPD with dissociation (Tables 2,3), consistent with western research (5,9,12,39). While amnesia was more often reported in our DDIS MPD+ group vs non-MPD group, there was no difference in this variable between the group who filled the DSM III-R criteria for borderline personality and those who did not, consistent with western studies (5,12,41) that showed that amnesia distinguished MPD from BPD.
While our data is based on only 9 DDIS MPD+ subjects, this adds to the already significant literature. Table 3 shows that while BPD is associated with considerable dissociative experiences, DES score of 24.4 for the BPD group vs. 8.7 for the non-BPD group, this score is still considerably lower than the score of 41.4 in a North American sample of 82 patients with MPD (37). Patients with MPD symptom-atology exhibit significant borderline pathology,and vice-versa , and this may relate to similarly disruptive childhood experiences and use of maladaptive defenses. Dissociative experiences seem to occur in a wide range of psychiatric pathology, just as depression and anxiety may occur in various disorders (30).
An additional finding was the lack of any association in our patients with dissociation and suicide attempts/ideation as had been found in the western research (12,42,43)
This preliminary study is the first to find systematic evidence of considerable dissociative symptomatology and child abuse in a Japanese psychiatric population, and is an addition to the literature that dissociation and MPD related symptomatology are world-wide phenomena. There was also a considerable amount of physical and sexual abuse in our eating disorder subjects' histories although we did not ascertain the exact severity of abuse. If the lack of association of sexual abuse histories with dissociation in Japan is replicated in larger samples it will be important to look into those aspects of Japanese society that make this a divergent finding from western studies.
This study suggests that it will be important for Japanese clinicians to become more acquainted with dissociative symptoms and the psychological effects of child abuse so that improved detection and treatment for these problems can be instituted. Future studies need to further clarify the relationships between sexual abuse, dissociation, and eating disorders in Japan.
1.) Takahashi Y: Is multiple personality really rare in Japan? Dissociation l990; 3(2): 57-59
2.) Taboas AM: Reflections on Takahashi's methodology and the role of culture on MPD. Dissociation 1990; 3(2): 62
3.) American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 3rd ed, Revised, Washington DC American Psychiatric Assn. 1987
4.) Ross CA, Heber S, Norton GR, Anderson G: Somatic symptoms in multiple personality disorder. Psychosomatics 1989; 30(2): 154-160
5.) Boon S, Draijer N: Diagnosing dissociative disorders in the Netherlands: a pilot study with the structured clinical intetrview for DSM III-R dissociative disorders. Am J Psychiatry 1991; 148(4): 458-462
6.) Coons PM, Bowman ES, Milstein V: Multiple personality disorder, a clinical investigation of 50 cases. J of Nervous and Mental Dis 1988;176(9): 519-527
7.) Kaplan H, Sadock B (eds): Synopsis of Psychiatry, 5th ed, Williams and Wilkins, Baltimore MD, 1988
8.) Torem MS: Covert multiple personality underlying eating disorders. Am J Psychotherapy l990; 44(3): 357-368
9.) Ross CA, Heber S, Norton GR, Anderson D, Anderson G, Barchet P: The dissociative disorders interview schedule: a structured interview. Dissociation 1989; 2(3):169-189
10.) Task Force on DSM IV: DSM IV Draft Criteria. American Psychiatric Association, March 1, 1993
11.) Fahy TA: The diagnosis of multiple personality disorder: a critical review. Br J Psychiatry 1988; 153:597-606
12.) Boon S, Draijer N: Multiple personality disorder in the Netherlands: a clinical investigation of 71 patients. Am J Psychiatry 1993; 150: 489-494
13.) Modestin J: Multiple personality disorder in switzerland. Am J Psychiatry 1992; 149:88-92
14.) Ross CA: Epidemiology of Multiple Personality disorder and dissociation. Psychiatric Clinics of North America 1991; 14:503-515
15.) Adityanjee R, Khandelwal SK: Current status of multiple personality disorder in India. Am J Psychiatry 1989; 146:1607-1610
16.) Ross CA: Comments on Takahashi's: "is mpd really rare in Japan?". Dissociation 1990; 3:64
17.) Frischholz EJ, Braum BG: Comment on "Is mpd really rare in Japan".Dissociation 1990; 3:60-61
18.) Ogino K: Introductory Lecture on Psychopathology. (In Japanese),Tokyo, Seishin-shobo, 1964
19.) Saito M, Miyazaki T: A case of multiple personality. (In Japanese), Seishin Igaku 1978; 20:257-263
20.) Oppenheimer R, Howells K, Palmer RL, Chaloner DA: Adverse sexual experience in childhood and clinical eating disorders: a preliminary description. J Psychiatric Res 1985; 19:357-361
21.) Sloan G, Leichner P: Is there a relationship between sexual abuse or incest and eating disorders? Can J Psychiatry l986; 31:656-660
22.) Hall RC, Tice L, Beresford TP, Wooley B, Klassen Hall A: Sexual abuse in patients with anorexia nervosa and Bulimia. Psychosomatics 1989; 30:73-79
23.) Shearer SL, Peters CP, Quaytman MS, Ogden RL: frequency and correlates of childhood sexual and physical abuse histories in adult female borderline inpatients. Am J Psychiatry 1990, 147: 214-216
24.) Demitrack MA, Putna FW, Brewerton TD, Brandt HA, Gold PW: Relation of clinical variables to dissociative phenomena in eating disorders. Am J Psychiatry 1990; 147: 1184-1188
25.) Coons P, Bowman ES: Dissociation and eating. Am J Psychiatry (Letter) 1993; 150:171
26.) Chandarana MB, Malla MB: Bulimia and dissociative states: a case report. Can J Psychiatry 1989; 34:137-139
27.) Torem M: Dissociative states presenting as eating disorders. Am J Clin Hypn 1986; 29:137-142
28.) Moss P: Dissociative disorders clinical update. Carrier Foundation Medical Education Letter 1993; No.176:1-2,7
29.) Bernstein EM, Putnam FW: Development, reliability, and validity of a dissociation scale. J of Nervous and Mental disease 1986,174.727-735
30.) Ross CA, Joshi S, Currie R: Dissociative experiences in the general population. Am J Psychiatry 1990; 147;1547-1552
31.) Ross CA, Norton GR, Anderson G: The dissociative experiences scale a replication study. Dissociation 1988; 1: 21-22
32.) Tanabe H, Ogawa T: On the measurement of dissociative experiences: development of the dissociative experiences scale with a population of Japanese University Students.Tsukuba Psychological Research (In Japanese)1992; 14:171-178
33.) Berger D, Ono Y, Nakajima K, Suematsu H: Dissociative symptomatology in Japan. Am J Psychiatry (Letter)1994; 151:148-149
34.) Hollingshead AB, Redlich FC: Social Class and Mental Illness. JohnWiley and Sons Inc. 1958
35.) Ross CA, Heber S, Norton R, Andersson G: Differences betweeen multiple personality and other diagnostic groups on structured interview. J of Nervous and Mental Disease 1989; 177:487-491
36.) Hornstein NL, Putnam FW: Clinical phenomenology of child and adolescent dissociative disorders. J Am Acad Child Adoles Psychiatry 1992; 31:1077-85
37.) Putnam FW, Guroff JJ, Silberman EK, Barban L, Post RM: The clinical phenomenology of multiple personality dosorder: review of 100 cases. J clin Psychiatry 1986; 47:285-293
38.) Ross CA, Norton GR, Wozney K: Multiple personality disorder: an analysis of 236 cases. Can J Psychiatry 1989; 34:413-418
39.) Ross CA, Miller SD, Reagor P, Bjornson L, Fraser GA, Anderson G: Structured interview data on 102 cases of multiple personality disorder from four centers. Am J Psychiatry 1990; 147:596-601
40.) Frankel FH: Adult reconstruction of childhood events in the multiple personality literature. Am J Psychiatry; 150: 954-958
41.) Fink D, Golninkoff M: Multiple personality disorder, borderline personality disorder and schizophrenia: a comparative study of clinical features. Dissociation; 3:127-133
42.) Ross CA, Norton GR: Suicide and parasuicide in multiple personality disorder. Psychiatry 1989; 52: 365-371
43.) Coons PM, Milstein V: Self-mutilation associated with dissociative disorders. Dissociation 1990; 3(2): 81-87
東京大学医学部 バーガー ダグラス 久保木 富房 末松 弘行
慶応義塾大学 大野 裕 白波瀬 丈一郎
東京都精神医学総合研究所 斎藤 学 手塚 一朗
本研究は摂食障害にみられた解離症状、特に多重人格について研究し、さらに解離症状と 小児期の虐待との関係について検討したものである。欧米ではこうした研究が数多く報告 されているが、日本ではほとんど体系的に研究が行われていない。そこで摂食障害患者に 対する外来集団治療受けている４４例の女性患者に、北米で使われている解離体験調査紙 「DES」と自己記入式解離障害面接紙「DDIS」修正版を施行した。
DDISを記入した４１ 例患者の内DSM III-Rの多重人格の診断基準を満たしたのは９例であった。DESを記入し た３９例の患者の内６例はDESが３０点以上であり、心的外傷後ストレス障害や多重人格 である可能性が高いことが示唆された。解離症状を多く示した患者の特徴は、欧米で行わ れた研究結果と類似していた。摂食障害患者の小児期の性的／身体的総合虐待率は４５。 ５％、性的のみの虐待率は３６。３％、身体的のみの虐待率は２５。０％。わが国の摂食 障害患者の性的虐待率は、日本政府統計による一般人口のそれよりもかなり多く、欧米の 摂食障害患者における性的虐待率に近い値を示した。解離症状の有無と小児期の身体的虐 待体験との間には有意な相関が認められたが、解離症状の有無と小児期の性的虐待体験と の間には有意な相関は認められなかった。