Clinically meaningful changes in functional performance resulting from self-directed interventions in individuals with arthritis

Abstract Objectives To examine the clinical meaningfulness of changes observed in functional performance from two self-directed interventions targeting adults with arthritis. Study design Randomized controlled trial. Methods Participants ( n  = 312) were randomized to a 12-week self-directed exercise or nutrition intervention. Objective measures of functional performance (6-minute walk, seated reach, grip strength, 30-second chair stand, gait speed, balance) were obtained at baseline, 12 weeks, and nine months. Minimally (≥0.20 standard deviation) and substantially (≥0.50) meaningful changes in functional performance were examined. Changes in the percent ‘impaired’ and at risk for losing independence using established standards, and associations between physical activity and impairment/risk status were also examined. Group × Time interactions were not significant; therefore groups were combined in all analyses. Results Minimally (31–71%) and substantially (13–54%) meaningful changes in function were shown. There was a significant decrease in the percentage of participants ‘impaired’ on the 30-second chair stand (both time points) and gait speed (nine months). The percentage of participants at risk for losing independence significantly decreased for the 30-second chair stand (both time points) and the 6-minute walk (nine months). Those engaging in ≥2 h of leisure-time physical activity were significantly less likely to be impaired on the 6-minute walk, 30-second chair stand, and gait speed at 12 weeks, and the 6-minute walk at nine months. Conclusions Interventions that can slow functional declines, and ideally result in clinically meaningful improvements in functional performance among adults with arthritis are needed. Meaningful improvements in various indicators of functional performance can result from self-directed exercise and nutrition programs. These types of programs have the potential for wide-spread dissemination, and thus broad reach.