Abstract
I) Statistical studies on anorexia nervosa in Japan were carried out by our research group. Questionnaires were sent to physicians at 1,030 representative institutions throughout Japan and data were collected from 315 institutions. The total number of patients with anorexia nervosa in 1981 was 940 outpatients and 372 inpatients. The number of patients in 1981 was twice as high as in 1976. Detailed data on 1,011 patients were investigated. of the 1,011 patients, 4% (41) were males. The average onset age was 18 years. The incidence of signs, symptoms, abnormalitics of laboratory data and endocrinological data were investigated. The outcome of 418 of the 1,011 cases was judged by their doctors as 'good' in 186 cuses (44%), 'intermediate' in 162 cases (39%) and 'poor' in 58 cases (14%). 12 cases (3%) of the patients had died. Unsatisfactory outcome appear to be associated with clinical data such as late onset of the disease. presence of synptoms such as bulimia, vomiting, abuse of laxatives and weak selfcontrol. A number of the patients expressed a desire to remain single. Mensses returned in 74% of the patients. In 24% of them, the menstral rhythm remained irregular. I) As anorexia nervosa patients often deny the existence ol disease, and as they tend not to seek hospital treatment, further investigation on the prevalence of anorexia nervosa among school girls were carried out. It is suspected that there are several school girls with anorexia nervosa ro borderline-anorexia nervosa And there are also many cases of those who show eiting disorders or desire to reduce body weight. In these cases rates are found to be higher in senior high school students and students in the city. III) h the etiology of anorexia nervosa, which is more important, hereditary or environment? This question was examined by studying seven cases of anorexia nervosa in monozygotic twins in the authors' own practice. In 5 of 7cases, only one of a set of twins was found to be suffering from anorexia nervosa. On the other hand, in 2 of 7 cases, both the twins were diagnosed as having anorexia nervosa. Even in the concordant cases studied by the authors, however, the quality or degree of anorexia nervosa between each case was different. Therefore, even given the existence of concordant cases, without inquiring precisely into the quality or degree of anorexia nervosa, it is not possible to conclude that hereditary factors phy a determining role in the etiology of anorexia nervosa.
