Background Osteoarthritis (OA) is a leading cause of activity limitations among older adults. The knee OA population is heterogeneous and is likely to consist of subgroups with distinct trajectories of activity limitations.
Objectives 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.
Methods Follow-up data over a period of five years of 697 participants with early symptomatic knee OA from the Cohort Hip and Cohort Knee (CHECK) were used. Activity limitations were measured yearly (six measurements over time) 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.
Results 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 to the ‘good outcome’ subgroup, the (‘moderate outcome’ and ‘poor outcome’ subgroups were characterized 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.
Conclusions Based on the 5-year course of activity limitations examined in our study, 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. Identification of homogeneous subgroups may contribute to the development of tailored preventive interventions in knee OA patients.
Disclosure of Interest None Declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.