背景:首发精神病(FEP)的发病率在地理区域之间有很大差异。亚临床精神病(SP)的表型,如精神病样经历(PLE)和分裂型,与精神病有几个相似之处。我们的目的是检查不同地点的SP测量是否不同,以及这种变化是否与相同地区的FEP发生率相当。我们进一步研究了环境和遗传因素对SP的贡献。
方法:我们使用了来自6个国家的16个不同地点招募的1497名对照的数据。使用多维项目反应理论模型获得了分裂型和PLE的几个心理病理学维度的因子得分。使用多水平回归分析评估这些分数的变化,以估计调整年龄的个体和站点之间的差异,性别,教育,移民,就业和关系状况,童年的逆境,使用大麻。在最终模型中,我们添加了局部FEP发生率作为二级变量。与遗传责任的关联进行了单独检查。
结果:分裂型显示出很大的位点间变异,其中高达15%的变异归因于位点水平的特征。将局部FEP发生率添加到模型中,大大减少了位点间无法解释的分裂型变异。PLEs没有显示出很大的变化。总的来说,SP与年龄较小有关,移民,未婚,失业和受教育程度较低的人,使用大麻,和童年的逆境。两种表型均与精神分裂症的遗传倾向相关。
结论:分裂型显示出大量的位点间变异,在FEP发病率较高的地区有更多的代表。这支持以下假设:共享的上下文因素会影响整个频谱中精神病的站点之间的变化。
BACKGROUND: Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP.
METHODS: We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately.
RESULTS: Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia.
CONCLUSIONS: Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.