Cannon Tyrone D, Yu Changhong, Addington Jean, Bearden Carrie E, Cadenhead Kristin S, Cornblatt Barbara A, Heinssen Robert, Jeffries Clark D, Mathalon Daniel H, McGlashan Thomas H, Perkins Diana O, Seidman Larry J, Tsuang Ming T, Walker Elaine F, Woods Scott W, Kattan Michael W
From the Departments of Psychology and Psychiatry, Yale University, New Haven, Conn.; the Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland; the Hotchkiss Brain Institute, Department of Psychiatry, University of Calgary, Alberta; the Departments of Psychiatry and Biobehavioral Sciences and Psychology, UCLA, Los Angeles; the Department of Psychiatry, UCSD, San Diego; the Department of Psychiatry, Zucker Hillside Hospital, Glen Oaks, New York; NIMH, Bethesda, Md.; the Renaissance Computing Institute, University of North Carolina, Chapel Hill; the Department of Psychiatry, UCSF, San Francisco; the Department of Psychiatry, University of North Carolina, Chapel Hill; the Department of Psychiatry, Harvard Medical School at Beth Israel Deaconess Medical Center and Massachusetts General Hospital, Boston; the Center for Behavioral Genomics, the Department of Psychiatry, and the Institute of Genomic Medicine, UCSD, La Jolla; and the Departments of Psychology and Psychiatry, Emory University, Atlanta.
Am J Psychiatry. 2016 Oct 1;173(10):980-988. doi: 10.1176/appi.ajp.2016.15070890. Epub 2016 Jul 1.
Approximately 20%-35% of individuals 12-35 years old who meet criteria for a prodromal risk syndrome convert to psychosis within 2 years. However, this estimate ignores the fact that clinical high-risk cases vary considerably in risk. The authors sought to create a risk calculator, based on profiles of risk indicators, that can ascertain the probability of conversion to psychosis in individual patients.
The study subjects were 596 clinical high-risk participants from the second phase of the North American Prodrome Longitudinal Study who were followed up to the time of conversion to psychosis or last contact (up to 2 years). The predictors examined were limited to those that are supported by previous studies and are readily obtainable in general clinical settings. Time-to-event regression was used to build a multivariate model predicting conversion, with internal validation using 1,000 bootstrap resamples.
The 2-year probability of conversion to psychosis was 16%. Higher levels of unusual thought content and suspiciousness, greater decline in social functioning, lower verbal learning and memory performance, slower speed of processing, and younger age at baseline each contributed to individual risk for psychosis. Stressful life events, trauma, and family history of schizophrenia were not significant predictors. The multivariate model achieved a concordance index of 0.71 and, as reported in an article by Carrión et al., published concurrently with this one, was validated in an independent external data set. The results are instantiated in a web-based risk prediction tool envisioned to be most useful in research protocols involving the psychosis prodrome.
A risk calculator comparable in accuracy to those for cardiovascular disease and cancer is available to predict individualized conversion risks in newly ascertained clinical high-risk cases. Given that the risk calculator can be validly applied only for patients who screen positive on the Structured Clinical Interview for Psychosis Risk Syndromes, which requires training to administer, its most immediate uses will be in research on psychosis risk factors and in research-driven clinical (prevention) trials.
符合前驱风险综合征标准的12至35岁个体中，约20% - 35%会在2年内发展为精神病。然而，这一估计忽略了临床高危病例风险差异很大这一事实。作者试图基于风险指标概况创建一个风险计算器，以确定个体患者发展为精神病的概率。
研究对象为北美前驱期纵向研究第二阶段的596名临床高危参与者，随访至发展为精神病或最后一次接触（最长2年）。所检查的预测因素限于先前研究支持且在一般临床环境中易于获得的因素。采用事件发生时间回归构建预测转化的多变量模型，并使用1000次自助重采样进行内部验证。
2年内发展为精神病的概率为16%。异常思维内容和猜疑程度较高、社会功能下降幅度较大、言语学习和记忆表现较低、处理速度较慢以及基线年龄较小，均会增加个体患精神病的风险。生活应激事件、创伤和精神分裂症家族史并非显著的预测因素。多变量模型的一致性指数为0.71，并且正如与本文同时发表的卡里翁等人的一篇文章中所报道的，该模型在一个独立的外部数据集中得到了验证。研究结果体现在一个基于网络的风险预测工具中，该工具预计在涉及精神病前驱期的研究方案中最为有用。
一种准确性与心血管疾病和癌症风险计算器相当的风险计算器可用于预测新确诊的临床高危病例的个体化转化风险。鉴于该风险计算器仅适用于在精神病风险综合征结构化临床访谈中筛查呈阳性的患者，而该访谈需要经过培训才能实施，其最直接的用途将是在精神病风险因素研究以及以研究为驱动的临床（预防）试验中。
