The Relation of Activity Patterns with Incident Slow Gait Speed over 4 Years in Adults with Knee Osteoarthritis: Data from the Osteoarthritis Initiative

The purpose of this study was to explore patterns of baseline physical activity using Multilevel Functional Principal Components Analysis (MFPCA) and examine the relation of these patterns with incident slow gait speed over 4 years in adults with or at high risk of knee OA utilizing data from the accelerometer sub-study of the Osteoarthritis Initiative (OAI).
For the purpose of the study, Multilevel Functional Principal Components Analysis was done. As a result of the analysis, it was determined that there were 4 activity patterns (PCs), 1) high activity, 2) high evening activity, 3) high morning and evening activity, and 4) very high morning activity.
Those whose daily activity patterns best matched with the pattern PC2 or PC4, were found to have 0.60 and 0.39 times the risk of developing slow gait speed, respectively; while those whose daily activity patterns least matched PC3, were found to have 1.77 times the risk.
Our study results suggest that daily activity patterns may be associated with the development of slow gait speed in adults with or at risk for knee OA.