Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases (NCRC-DID), State Key Laboratory of Complex Severe and Rare Diseases, The Ministry of Education Key Laboratory, Beijing, China.
Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases (NCRC-DID), State Key Laboratory of Complex Severe and Rare Diseases, The Ministry of Education Key Laboratory, Beijing, China
RMD Open. 2024 Mar 8;10(1):e003938. doi: 10.1136/rmdopen-2023-003938.
To develop and conduct an initial validation of the Damage Index for IgG4-related disease (IgG4-RD DI).
A draft of index items for assessing organ damages in patients with IgG4-RD was generated by experts from the Chinese IgG4-RD Consortium (CIC). The preliminary DI was refined using the Delphi method, and a final version was generated by consensus. 40 IgG4-RD cases representing four types of clinical scenarios were then selected, each with two time points of assessment for at least 3 years of follow-up. 48 rheumatologists from 35 hospitals nationwide were invited to evaluate organ damage using the CIC IgG4-RD DI. The intraclass correlation coefficient (ICC) and the Kendall-W coefficient of concordance (KW) were used to assess the inter-rater reliability. The criterion validity of IgG4-RD DI was tested by calculating the sensitivity and specificity of raters.
IgG4-RD DI is a cumulative index consisting of 14 domains of organ systems, including a total of 39 items. The IgG4-RD DI was capable of distinguishing stable and increased damage across the active disease subgroup and stable disease subgroup. In terms of scores at baseline and later observations by all raters, overall consistency in scores at baseline and later observations by all raters was satisfactory. ICC at the two time points was 0.69 and 0.70, and the KW was 0.74 and 0.73, respectively. In subgroup analysis, ICC and KW in all subgroups were over 0.55 and 0.61, respectively. The analysis of criterion validity showed a good performance with a sensitivity of 0.86 (95% CI 0.82 to 0.88), a specificity of 0.79 (95% CI 0.76 to 0.82) and an area under the curve of 0.88 (95% CI 0.85 to 0.91).
The IgG4-RD DI is a useful approach to analyse disease outcomes, and it has good operability and credibility. It is anticipated that the DI will become a useful tool for therapeutic trials and studies of prognosis in patients with IgG4-RD.
开发并初步验证 IgG4 相关疾病（IgG4-RD）损伤指数（IgG4-RD DI）。
中国 IgG4-RD 联盟（CIC）的专家制定了用于评估 IgG4-RD 患者器官损伤的指标草案。采用德尔菲法对初步 DI 进行了修订，并通过共识生成了最终版本。然后选择了 40 例代表四种临床情况的 IgG4-RD 病例，每个病例均有至少 3 年随访的两个评估时间点。邀请全国 35 家医院的 48 名风湿病学家使用 CIC IgG4-RD DI 评估器官损伤。采用组内相关系数（ICC）和 Kendall-W 一致性系数（KW）评估评分者间的信度。通过计算评分者的灵敏度和特异性来检验 IgG4-RD DI 的标准效度。
IgG4-RD DI 是一个由 14 个器官系统域组成的累积指数，共 39 项。IgG4-RD DI 能够区分活动期亚组和稳定期亚组的稳定和增加的损伤。在所有评分者的基线和后续观察评分方面，基线和所有评分者的后续观察评分的总体一致性令人满意。两个时间点的 ICC 分别为 0.69 和 0.70，KW 分别为 0.74 和 0.73。在亚组分析中，所有亚组的 ICC 和 KW 均大于 0.55 和 0.61。标准效度分析显示，具有 0.86（95%CI 0.82 至 0.88）的高灵敏度、0.79（95%CI 0.76 至 0.82）的高特异性和 0.88（95%CI 0.85 至 0.91）的曲线下面积。
IgG4-RD DI 是分析疾病结局的一种有用方法，具有良好的操作性和可信度。预计该指数将成为 IgG4-RD 患者治疗试验和预后研究的有用工具。
