Franzek E, Beckmann H
Department of Psychiatry, University of Wuerzburg, Germany.
Am J Psychiatry. 1998 Jan;155(1):76-83. doi: 10.1176/ajp.155.1.76.
The authors report on a systematic twin study of index twins suffering from schizophrenia spectrum psychoses. Using different diagnostic systems, they examined twin concordance, family history, and the frequency and severity of the birth complications of 22 monozygotic and 23 dizygotic twin pairs.
All twins in the region of Lower Franconia, Germany, born after 1930 and hospitalized for psychiatric disease were ascertained. The zygosity diagnoses were based on molecular genetic methodology and a zygosity questionnaire. Two psychiatrists, working independently, formulated diagnoses according to DSM-III-R criteria and Leonhard's nosology.
There were substantially different concordance rates with regard to diagnostic subgroups, and monozygotic concordance was significantly higher than dizygotic concordance in only two of the following five subgroups (subgroups 1 and 3): 1) strict schizophrenia according to DSM-III-R: monozygotic, 85.7%, dizygotic, 25.0%; 2) schizophreniform, schizoaffective, and delusional (paranoid) disorders and psychotic disorder not otherwise specified according to DSM-III-R: monozygotic, 47.1%, dizygotic, 30.8%; 3) unsystematic schizophrenia according to Leonhard: monozygotic, 88.9%, dizygotic, 25.0%; 4) systematic schizophrenia according to Leonhard: monozygotic pairs lacking, dizygotic, 0%; 5) cycloid psychoses according to Leonhard: monozygotic, 38.5%, dizygotic, 36.4%. In the case of cycloid psychoses and conditions less prominent in DSM-III-R schizophreniform, schizoaffective, and delusional (paranoid) disorders and psychotic disorder not otherwise specified, the affected twins had suffered significantly more severe birth complications than their healthy partners. Not one of the 37 monozygotic twins was diagnosed as having systematic schizophrenia, whereas six of the 25 dizygotic index twins received this diagnosis.
The results of the study suggest that schizophrenia spectrum psychoses may consist of clinically and etiologically heterogeneous subgroups with different genetic backgrounds.
作者报告了一项针对患有精神分裂症谱系精神病的索引双胞胎的系统双生子研究。他们使用不同的诊断系统，检查了22对同卵双胞胎和23对异卵双胞胎的双生子一致性、家族史以及出生并发症的频率和严重程度。
确定了德国下弗兰肯地区1930年以后出生且因精神疾病住院的所有双胞胎。合子性诊断基于分子遗传学方法和一份合子性问卷。两名精神科医生独立工作，根据DSM-III-R标准和莱昂哈德分类法制定诊断。
在诊断亚组方面，一致性率存在显著差异，在以下五个亚组中的仅两个亚组（亚组1和3）中，同卵双胞胎的一致性显著高于异卵双胞胎：1）根据DSM-III-R的严格精神分裂症：同卵双胞胎，85.7%；异卵双胞胎，25.0%；2）根据DSM-III-R的精神分裂症样、分裂情感性和妄想性（偏执性）障碍以及未另行规定的精神障碍：同卵双胞胎，47.1%；异卵双胞胎，30.8%；3）根据莱昂哈德的非系统性精神分裂症：同卵双胞胎，88.9%；异卵双胞胎，25.0%；4）根据莱昂哈德的系统性精神分裂症：同卵双胞胎无，异卵双胞胎，0%；5）根据莱昂哈德的循环性精神病：同卵双胞胎，38.5%；异卵双胞胎，36.4%。在循环性精神病以及在DSM-III-R精神分裂症样、分裂情感性和妄想性（偏执性）障碍以及未另行规定的精神障碍中不太突出的情况中，患病双胞胎比其健康的同胞出生并发症严重得多。37对同卵双胞胎中没有一对被诊断为患有系统性精神分裂症，而25对异卵索引双胞胎中有6对得到了这一诊断。
该研究结果表明，精神分裂症谱系精神病可能由具有不同遗传背景的临床和病因异质性亚组组成。
