Cooper B, Eagles J M
Department of Epidemiological Psychiatry, Zentralinstitut für Seelische Gesundheit, Mannheim, Germany.
Br J Psychiatry. 1994 Jan;164(1):97-100. doi: 10.1192/bjp.164.1.97.
"STUDY OBJECTIVE--The aim was to examine why differences exist in schizophrenia prevalence and risk in some areas of Croatia, when schizophrenia incidence rates do not appear to vary. DESIGN--Areas differing by schizophrenia admission rates in patients born in 1953 and admitted by the age of 31 years are compared using a number of indicators relating both to general population characteristics and to those of schizophrenic cases in these populations. SETTING--The study covers the whole of Croatia (4,601,469 inhabitants, 1981 census). SUBJECTS--By the age of 31 years, out of 80,445 individuals born in Croatia in 1953, 464 were admitted for and diagnosed as having schizophrenia. MAIN RESULTS--Admission risk rates are higher in those parts of Croatia where emigration rates are high and lower where immigration rates are high. There is also a positive correlation with schizophrenia prevalence and manic depressive psychosis rates. There is a negative correlation with age of onset of schizophrenia and with schizophrenic reproduction rates. In the study areas, hospital incidence rates are not significantly different. CONCLUSIONS--Economic migration and negative selection in the domestic population are likely to be the most significant factors leading to differences in schizophrenia prevalence. The approximately equal incidence rates in the population, with different prevalence and admission risks, are linked to differences in the disease onset among schizophrenics with a positive family history for this condition. In other words, these patients, when part of the population with a greater prevalence and a greater hereditary loading, experience the onset more often at an earlier age. Thus they have a lower reproduction rate than in a population with a lower prevalence and a lower hereditary loading. Thus incidence rates in populations with different prevalences and different hereditary loads are maintained roughly equal over generations."
研究目的——旨在探讨克罗地亚某些地区精神分裂症患病率和风险存在差异的原因，而这些地区的精神分裂症发病率似乎并无变化。设计——采用一系列与总体人群特征以及这些人群中精神分裂症病例特征相关的指标，对1953年出生且31岁前入院的患者中，精神分裂症入院率不同的地区进行比较。研究背景——研究涵盖克罗地亚全境（1981年人口普查时为4,601,469居民）。研究对象——在1953年出生于克罗地亚的80,445人中，到31岁时，有464人因精神分裂症入院并被诊断为此病。主要结果——克罗地亚移民率高的地区，精神分裂症入院风险率较高；而移民率高的地区则较低。精神分裂症患病率和躁狂抑郁症发病率之间也存在正相关。与精神分裂症发病年龄以及精神分裂症繁殖率呈负相关。在研究地区，医院发病率并无显著差异。结论——经济移民和国内人口的负性选择可能是导致精神分裂症患病率存在差异的最重要因素。在人口中发病率大致相同，但患病率和入院风险不同，这与有精神分裂症家族史的精神分裂症患者发病差异有关。换句话说，这些患者在患病率和遗传负荷较高的人群中，发病年龄往往更早。因此，他们的繁殖率低于患病率和遗传负荷较低的人群。这样，不同患病率和不同遗传负荷人群的发病率在几代人中大致保持相等。
