From the British Columbia Children's Hospital and the University of British Columbia, Vancouver; Simon Fraser University, Burnaby, British Columbia; London Health Sciences Centre and Western University, London; Children's Hospital of Eastern Ontario and University of Ottawa, Ottawa, Ontario; IWK Health Centre and Dalhousie University, Halifax, Nova Scotia; Winnipeg Children's Hospital and University of Manitoba, Winnipeg, Manitoba; Hospital for Sick Children and University of Toronto, Toronto, Ontario; McGill University Health Centre and McGill University, Montreal, Quebec; Janeway Children's Health and Rehabilitation Centre and Memorial University, Saint John's, Newfoundland and Labrador; Royal University Hospital and University of Saskatchewan, Saskatoon, Saskatchewan; Centre Hospitalier Universitaire Sainte-Justine and Université de Montréal, Montreal; Centre Hospitalier Universitaire de Sherbrooke and Université de Sherbrooke, Sherbrooke, Quebec; Alberta Children's Hospital and University of Calgary, Alberta, Canada; Shands Children's Hospital and University of Florida, Gainesville, Florida, USA.
The Research in Arthritis in Canadian Children Emphasizing Outcomes cohort was funded by a New Emerging Team research grant from the Canadian Institutes of Health Research (funding reference QNT 69301). Dr. Guzman was funded by a Clinical Investigator Award from the BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.
J Rheumatol. 2019 Jun;46(6):628-635. doi: 10.3899/jrheum.180456. Epub 2019 Jan 15.
To estimate the probability of early remission with conventional treatment for each child with juvenile idiopathic arthritis (JIA). Children with a low chance of remission may be candidates for initial treatment with biologics or triple disease-modifying antirheumatic drugs (DMARD).
We used data from 1074 subjects in the Research in Arthritis in Canadian Children emphasizing Outcomes (ReACCh-Out) cohort. The predicted outcome was clinically inactive disease for ≥ 6 months starting within 1 year of JIA diagnosis in patients who did not receive early biologic agents or triple DMARD. Models were developed in 200 random splits of 75% of the cohort and tested on the remaining 25% of subjects, calculating expected and observed frequencies of remission and c-index values.
Our best Cox logistic model combining 18 clinical variables a median of 2 days after diagnosis had a c-index of 0.69 (95% CI 0.67-0.71), better than using JIA category alone (0.59, 95% CI 0.56-0.63). Children in the lowest probability decile had a 20% chance of remission and 21% attained remission; children in the highest decile had a 69% chance of remission and 73% attained remission. Compared to 5% of subjects identified by JIA category alone, the model identified 14% of subjects as low chance of remission (probability < 0.25), of whom 77% failed to attain remission.
Although the model did not meet our performance threshold (c-index > 0.70), it identified 3 times more subjects with low chance of remission than did JIA category alone, and it may serve as a benchmark for assessing value added by future laboratory/imaging biomarkers.
估计每个幼年特发性关节炎（JIA）患儿接受常规治疗早期缓解的概率。缓解可能性低的患儿可能是初始接受生物制剂或三联疾病修饰抗风湿药物（DMARD）治疗的候选者。
我们使用了加拿大儿童关节炎研究强调结果（ReACCh-Out）队列中 1074 名受试者的数据。预测结果为在未接受早期生物制剂或三联 DMARD 的患者中，JIA 诊断后 1 年内开始的≥6 个月临床无疾病活动。在 75%队列的 200 个随机划分中开发模型，并在其余 25%的受试者中进行测试，计算缓解的预期和观察频率以及 c 指数值。
我们最好的 Cox 逻辑模型结合了 18 个临床变量，中位数在诊断后 2 天，c 指数为 0.69（95%CI 0.67-0.71），优于单独使用 JIA 类别（0.59，95%CI 0.56-0.63）。概率最低十分位数的患儿缓解的概率为 20%，实际缓解率为 21%；概率最高十分位数的患儿缓解的概率为 69%，实际缓解率为 73%。与单独使用 JIA 类别识别出的 5%的受试者相比，该模型识别出 14%的受试者缓解概率较低（概率<0.25），其中 77%的患儿未达到缓解。
尽管该模型未达到我们的性能阈值（c 指数>0.70），但它识别出的缓解概率低的受试者比单独使用 JIA 类别多 3 倍，它可以作为评估未来实验室/成像生物标志物附加值的基准。
