Objective: To evaluate the classification criteria of early rheumatoid arthritis (ERA) and compare the sensitivity and specificity with the criteria of 1987 American College of Rheumatology (ACR) criteria and 2010 ACR/European League Against Rheumatism (EULAR).
Methods: Patients from 4 hospitals, aged more than 16 years, with arthritis, whose disease duration was ≤1 year, and with ≥1 joint pain and swelling were enrolled in the study. The indicators including clinical manifestations, laboratory tests and imaging examinations were observed. The ERA patients were dignosed by two experienced rheumatologists based on the clinical features, drug therapy information and radiography features.
Results: (1) A total of 325 patients with arthritis were enrolled, including 98 males (30.15%) and 227 females (69.85%), The average age was (47.53±14.44) years, and the median disease duration was 5 (2, 8) months. Finally, 236 patients were dignosed with ERA, and 89 patients were dignosed with other diseases (Non-ERA, including osteoarthritis, reactive arthritis, undifferentiated arthritis, spondyloarthritis, etc). (2) The sensitivity of ERA criteria was 87.29%, and the specificity was 84.37%. The sensitivity was higher than that of 1987 ACR criteria (χ2=43.641, P < 0.001), and had no significant difference compared with 2010 ACR/EULAR criteria (χ2=0.446, P=0.593). But the specificity of ERA criteria was lower than that of 1987 ACR criteria (χ2=4.891, P=0.027), which was not statistically significant compared with 2010 ACR/EULAR criteria (χ2=0.044, P=1.000). (3) In the patients with arthritis whose disease duration was ≤3 months and ≤6 months, the sensitivity of ERA criteria was 81.71% and 86.79%, respectively, both were higher than the 1987 ACR criteria (χ2=7.131, P=0.008; χ2=22.015, P < 0.001) and had no statistically difference compared with the 2010 ACR/EULAR criteria (χ2=0.220, P=0.755; χ2=0.473, P=0.491). The differences of the three criteria in specificity were not statistically significant. (4) The three different classification criteria were consistent with the clinical diagnosis, among which the ERA criteria and 2010 ACR/EULAR criteria were slightly higher (Kappa>0.6). The results of the consistency comparison between the three criteria showed that the ERA criteria and 2010 ACR/EULAR criteria had a better consistency (Kappa=0.836).
Conclusion: The sensitivity of ERA classification criteria in the diagnosis of ERA was higher than that of 1987 ACR criteria, and was equivalent to that of 2010 ACR/EULAR criteria. There is no significant difference in specificity between these three criteria. The ERA criteria can also identify patients with RA at a very early stage in arthritis with disease duration ≤3 months.
目的: 验证并比较早期类风湿关节炎(early rheumatoid arthritis, ERA)分类标准与1987年美国风湿病学会(American College of Rheumatology, ACR)和2010年ACR/欧洲抗风湿联盟(European League Against Rheumatism, EULAR)制定的分类标准在ERA患者诊断中的敏感性和特异性。
方法: 在4所医院中入选年龄≥16岁、病程≤1年、存在≥1个关节肿痛的关节炎患者，观察指标包括临床表现、实验室检查及影像学检查。ERA的诊断经2名风湿病专科医师根据临床症状、用药情况、影像学检查进行临床诊断。
结果: (1) 共纳入关节炎患者325例，男性98例(30.15%)，女性227例(69.85%)，平均年龄(47.53±14.44)岁，中位病程5(2, 8)个月。最终诊断为ERA 236例，非ERA 89例(Non-ERA，包括骨关节炎、反应性关节炎、未分化关节炎、脊柱关节炎等)。(2) ERA标准的敏感性为87.29%，特异性为84.37%，敏感性高于1987年ACR标准(χ2=43.641，P＜0.001)，与2010年ACR/EULAR标准相比差异无统计学意义(χ2=0.446，P=0.593)；特异性低于1987年ACR年标准(χ2=4.891, P=0.027)，与2010年ACR/EULAR标准比较差异无统计学意义(χ2=0.044，P=1.000)。(3)在病程≤3个月和病程≤6个月关节炎患者中，ERA分类标准敏感性分别为81.71%、86.79%，均高于1987年ACR标准(χ2=7.131，P=0.008和χ2=22.015，P＜0.001)，与2010年ACR/EULAR标准比较差异无统计学意义(χ2=0.220，P=0.755和χ2=0.473，P=0.491)，3个标准的特异性比较差异均无统计学意义。(4) 3种分类标准与临床诊断存在一致性，其中ERA标准、2010年ACR/EULAR标准与临床诊断一致性较好(Kappa＞0.6)。3种分类标准间一致性比较结果提示，ERA标准与2010年ACR/EULAR标准间一致性较好(Kappa=0.836)。
结论: ERA分类标准在ERA诊断中的敏感性高于1987年ACR分类标准，与2010年ACR/EULAR年标准相当，3种标准间特异性比较差异无统计学意义；ERA标准在病程≤3个月的极早期关节炎中仍可识别出RA患者。
Keywords: Arthritis; Early diagnosis; Rheumatoid arthritis.