Amsterdam Rehabilitation Research Centre, Reade, Amsterdam, The Netherlands.
Amsterdam Rehabilitation Research Centre, Reade, Amsterdam, The Netherlands Department of Rehabilitation Medicine, VU University Medical Centre, Amsterdam, The Netherlands EMGO Institute for Health and Care Research, VU University Medical Centre, Amsterdam, The Netherlands.
Ann Rheum Dis. 2014 Jul;73(7):1369-75. doi: 10.1136/annrheumdis-2012-202984. Epub 2013 May 28.
Knee osteoarthritis (OA) is a leading cause of activity limitations. The knee OA population is likely to consist of subgroups. The aim of the present study was to identify homogeneous subgroups with distinct trajectories of activity limitations in patients with early symptomatic knee OA and to describe characteristics of these subgroups.
Follow-up data over a period of 5 years of 697 participants with early symptomatic knee OA from the Cohort Hip and Cohort Knee (CHECK) were used. Activity limitations were measured yearly with the Western Ontario and McMaster Universities Osteoarthritis Index. Latent class growth analyses identified homogeneous subgroups with distinct trajectories of activity limitations. Multivariable regression analyses examined differences in characteristics between the subgroups.
Three subgroups were identified. Participants in Subgroup 1 ('good outcome'; n=330) developed or displayed slight activity limitations over time. Participants in Subgroup 2 ('moderate outcome'; n=257) developed or displayed moderate activity limitations over time. Participants in subgroup 3 ('poor outcome'; n=110) developed or displayed severe activity limitations over time. Compared with the 'good outcome' subgroup, the 'moderate outcome' and 'poor outcome' subgroups were characterised by: younger age, higher body mass index, greater pain, bony tenderness, reduced knee flexion, hip pain, osteophytosis, ≥3 comorbidities, lower vitality or avoidance of activities.
Based on the 5-year course of activity limitations, we identified homogeneous subgroups of knee OA patients with good, moderate or poor outcome. Characteristics of these subgroups were consistent with existing knowledge on prognostic factors regarding activity limitations, which supports the validity of this classification.
膝骨关节炎（OA）是导致活动受限的主要原因。膝骨关节炎人群可能由亚组组成。本研究的目的是确定早期有症状的膝骨关节炎患者活动受限的同质亚组，并描述这些亚组的特征。
使用来自髋关节和膝关节队列研究（CHECK）的 697 名早期有症状的膝骨关节炎患者的 5 年随访数据。每年使用西安大略和麦克马斯特大学骨关节炎指数测量活动受限情况。潜在类别增长分析确定了具有不同活动受限轨迹的同质亚组。多变量回归分析检查了亚组之间特征的差异。
确定了三个亚组。第 1 组（“良好结果”；n=330）参与者随时间逐渐出现或仅显示轻度活动受限。第 2 组（“中等结果”；n=257）参与者随时间逐渐出现或显示中度活动受限。第 3 组（“较差结果”；n=110）参与者随时间逐渐出现或显示严重活动受限。与“良好结果”亚组相比，“中等结果”和“较差结果”亚组的特点是：年龄较小、身体质量指数较高、疼痛更剧烈、触诊有骨压痛、膝关节屈曲度降低、髋痛、骨赘形成、≥3 种合并症、活力较低或避免活动。
根据 5 年的活动受限病程，我们确定了具有良好、中等或较差结果的膝骨关节炎患者的同质亚组。这些亚组的特征与现有关于活动受限的预后因素的知识一致，这支持了这种分类的有效性。
