Kuper I H, van Leeuwen M A, van Riel P L, Sluiter W J, Houtman N M, Cats H A, van Rijswijk M H
Department of Rheumatology, University Hospital Groningen, The Netherlands.
J Rheumatol. 1999 Feb;26(2):268-76.
To evaluate at what disease duration and to what extent a ceiling effect, due to reaching maximum scores for erosions (E) and/or joint space narrowing (JSN) in separate joints, started to influence the assessment of radiographic progression according to the modified method of Sharp, in patients with recent onset rheumatoid arthritis (RA).
Prospective followup study of 87 patients with classical or definite RA, joint symptoms <1 year at study entry. Radiographs of hands and feet were made at study entry (Time 0), after 3 (T3), and after 6 years (T6) of followup. Assessment of radiographic progression according to the Van der Heijde modification of Sharp's method. The scores for E and JSN were analyzed separately in the individual groups of joints. Percentages of E joints, of joints with JSN, and of joints with maximum scores were assessed at T0, T3, and T6. The relative risks for the development of radiographic damage and of maximum scores were assessed for the individual joints. An approximation of the magnitude of the ceiling effect was calculated.
After a disease duration of 6 years, a significant influence of a ceiling effect on the mean radiographic progression was found. In some individual patients the ceiling effect appeared to occur earlier. After 6 years, the maximum scores were distributed over 50% of the patients, and 20% of the patients had maximum scores in more than 10 joints without preference for specific localization.
The ceiling effect appeared to be clinically relevant and should be taken into account when interpreting the effects of disease modifying antirheumatic drugs on radiographic progression in RA during the first years of the disease. Furthermore, it must be accounted for when describing the relationship between radiographic progression and process variables.
评估在近期发病的类风湿关节炎（RA）患者中，根据改良Sharp方法，由于单个关节的侵蚀（E）和/或关节间隙狭窄（JSN）达到最高分而导致的上限效应，会在疾病病程的何时以及在何种程度上开始影响放射学进展的评估。
对87例典型或确诊RA患者进行前瞻性随访研究，入组时关节症状出现<1年。在入组时（时间0）、随访3年（T3）和6年（T6）后拍摄手足X线片。根据Van der Heijde改良的Sharp方法评估放射学进展。在各个关节组中分别分析E和JSN的评分。在T0、T3和T6评估出现E的关节、出现JSN的关节以及达到最高分的关节的百分比。评估各个关节发生放射学损伤和达到最高分的相对风险。计算上限效应大小的近似值。
疾病病程6年后，发现上限效应对平均放射学进展有显著影响。在一些个体患者中，上限效应似乎出现得更早。6年后，最高分分布在50%的患者中，20%的患者在超过10个关节中出现最高分，且无特定部位偏好。
上限效应似乎具有临床相关性，在解释疾病修饰抗风湿药物对疾病最初几年RA放射学进展的影响时应予以考虑。此外，在描述放射学进展与病程变量之间的关系时也必须考虑到这一点。
