BACKGROUND Although cognitive problems have been identified in people with multiple sclerosis (PwMS), few studies have investigated the long-term change in cognitive functioning. OBJECTIVE To identify trajectories of change in cognitive functioning for PwMS. METHODS Participants enrolled in the quality-of-life subgroup from the Comprehensive Longitudinal Investigation of Multiple Sclerosis at Brigham and Women's Hospital (CLIMB) were eligible for our analysis. In 2006, participants in this group began to complete the Symbol Digit Modalities Test (SDMT) annually. Latent trajectory models were used to identify groups of participants with similar longitudinal change in SDMT scores. Linear and quadratic trajectory models were fit, and the models were compared. Latent trajectory models were also fit adjusting for baseline age and disease duration as well as using normalized SDMT scores. The groups identified across the approaches were compared. RESULTS We found that classes with higher-than-average baseline values improved, classes with average baseline values remained relatively constant, and classes with lower baseline values experienced cognitive worsening. Similar results were observed in the alternative latent trajectory models accounting for other variables. CONCLUSION Our models show that subjects with higher SDMT scores at baseline showed improvement, while subjects with lower SDMT scores at baseline showed worsening. Baseline age and disease duration were also associated with SDMT performance.

中文翻译：

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符号数字模式的轨迹测试多发性硬化症患者的表现

背景虽然已经在多发性硬化症 (PwMS) 患者中发现了认知问题，但很少有研究调查认知功能的长期变化。目的 确定 PwMS 认知功能变化的轨迹。方法 来自布里格姆妇女医院 (CLIMB) 多发性硬化综合纵向调查的生活质量亚组的参与者有资格进行我们的分析。2006 年，该组的参与者开始每年完成符号数字模态测试 (SDMT)。潜在轨迹模型用于识别 SDMT 分数具有相似纵向变化的参与者组。拟合线性和二次轨迹模型，并比较模型。潜在轨迹模型也适合调整基线年龄和疾病持续时间以及使用标准化的 SDMT 分数。比较了跨方法确定的组。结果我们发现，基线值高于平均水平的班级有所改善，平均基线值的班级保持相对稳定，而基线值较低的班级则经历了认知恶化。在考虑其他变量的替代潜在轨迹模型中观察到类似的结果。结论 我们的模型显示，基线时 SDMT 分数较高的受试者表现出改善，而基线时 SDMT 分数较低的受试者表现出恶化。基线年龄和病程也与 SDMT 的表现相关。结果我们发现，基线值高于平均水平的班级有所改善，平均基线值的班级保持相对稳定，而基线值较低的班级则经历了认知恶化。在考虑其他变量的替代潜在轨迹模型中观察到类似的结果。结论 我们的模型显示，基线时 SDMT 分数较高的受试者表现出改善，而基线时 SDMT 分数较低的受试者表现出恶化。基线年龄和病程也与 SDMT 的表现相关。结果我们发现，基线值高于平均水平的班级有所改善，平均基线值的班级保持相对稳定，而基线值较低的班级则经历了认知恶化。在考虑其他变量的替代潜在轨迹模型中观察到类似的结果。结论 我们的模型显示，基线时 SDMT 分数较高的受试者表现出改善，而基线时 SDMT 分数较低的受试者表现出恶化。基线年龄和病程也与 SDMT 的表现相关。在考虑其他变量的替代潜在轨迹模型中观察到类似的结果。结论 我们的模型显示，基线时 SDMT 分数较高的受试者表现出改善，而基线时 SDMT 分数较低的受试者表现出恶化。基线年龄和病程也与 SDMT 的表现相关。在考虑其他变量的替代潜在轨迹模型中观察到类似的结果。结论 我们的模型显示，基线时 SDMT 分数较高的受试者表现出改善，而基线时 SDMT 分数较低的受试者表现出恶化。基线年龄和病程也与 SDMT 的表现相关。