Risk of Knee Osteoarthritis Over 24 Months in Individuals Who Decrease Walking Speed During a 12-Month Period: Data from the Osteoarthritis Initiative

Abstract

Objective: To assess the association between change in walking speed over a 12-month period and risk of developing radiographic knee osteoarthritis (rKOA) over a 24-month period. Methods: We included participants without rKOA from the Osteoarthritis Initiative. Change in walking speed was determined from a 20-meter walk assessment, calculated using walking speed at 12-month follow-up minus baseline speed and/or 24-month follow-up walking speed minus 12-month speed. Incident rKOA was defined as progressing to Kellgren-Lawrence grade ≥2 within 24 months (i.e., incidence between 12 and 36 or 24 and 48 months). Self-reported significant knee injury during the exposure period, age, body mass index (BMI), and Physical Activity Scale for the Elderly (PASE) score were adjusted for analytically. Results: We included 2,638 observations among 1,460 unique participants (58% female; 59±9 years, range: 45–79). The mean change in walking speed over 12 months was 0.001±0.13 m/s (range: −0.6271, 1.4968). Approximately 5% of the sample (n=122) developed rKOA over a 24-month period. After controlling for significant knee injury, age, BMI, and PASE score, we found an 8% relative increase in risk of developing rKOA for every 0.1m/s decrease in walking speed over a 12-month period (Risk Ratio=1.08; 95% CI =1.00, 1.15; P = 0.05). Conclusion: Evaluating change in speed over a 12-month period using a 20-meter walk test may be useful in identifying individuals at increased risk of developing rKOA over the subsequent 24-months. Identification of patients at high risk for developing rKOA would allow medical providers to implement early interventions to maximize joint health.

Associations Between Slower Walking Speed and T1ρ Magnetic Resonance Imaging of Femoral Cartilage Following Anterior Cruciate Ligament Reconstruction

“…Walking speed is a simple performance outcome that clinicians can use to measure the functional status of individuals with knee OA (17) and predict the likelihood for OA development in those without knee OA (18,19). Slower walking speed has been found to predict fall risk (20), diminished performance in activities of daily living (ADLs) (18,21), and mortality in elderly individuals (22,23).…”

“…(18, 19) Slower walking speed has been found to predict fall risk,(20) diminished performance in activities of daily living,(18, 21) and mortality in elderly individuals. (22, 23) Purser et al(20) demonstrated that older healthy adults (60.07±9.86 years old) without knee OA who walked more slowly were more likely to develop knee OA over the following 6 years.…”

Association Between Declining Walking Speed and Increasing Bone Marrow Lesion and Effusion Volume in Individuals with Accelerated Knee Osteoarthritis

“…To assess habitual walking speed, we asked participants to perform 2 trials of a timed 20‐meter walk at their usual, comfortable walking pace . The participants began each trial in a stationary, standing position, and timing began when the participant took the first step at the starting line and ended when they passed a cone positioned 20 meters away.…”

“…Walking speed change was calculated as the index visit walking speed minus the walking speed of the year prior to the index visit. Based on a previous study, which detected an increase in the risk of knee OA in individuals decreasing their walking speed , we dichotomized walking speed change as slower/decline in walking speed (walking speed change less than or equal to −0.1 meter/second) and no change/increase in walking speed (walking speed change greater than −0.1 meter/second). This dichotomous variable allowed us to compare individuals with declining walking speed to individuals with no change/increase in walking speed.…”

“…Walking speed is an easily accessible clinical measure that reflects physical function in individuals with or at risk of knee osteoarthritis (OA) . Walking speed decline is a clinically relevant impairment that is a risk factor for developing radiographic knee OA and receiving a knee replacement . While walking speed decline is a prognostic marker of knee OA, how it relates to structural changes prior to the onset of radiographic OA remains unclear.…”