Exploring Changes in Activity Patterns in Individuals with Chronic Pain.

This longitudinal study explored whether activity patterns change over time in a sample of 56 individuals with chronic musculoskeletal pain over a 15-day period. Once a day, the participants recorded their level of pain intensity and the degree to which they had engaged in several specific activity patterns. Linear mixed models with random coefficients were used to investigate the rate of change in the activity patterns. Age, sex, pain intensity, and pain duration were controlled. The results show that excessive persistence was the only self-reported activity pattern to show a linear change over the 15-day period. There was a decrease in excessive persistence, and this decrease was slower with higher levels of activity avoidance. However, no significant association was found between sex, age, pain intensity, and pain duration and excessive persistence at baseline or change over time. At baseline, a positive association was found between excessive persistence and pain avoidance, pain-related persistence, and pacing to reduce pain, and a negative association was found between excessive persistence and pacing to save energy for valued activities. This result suggests a profile characterized by alternate periods of high and low activity that, in this study, were unrelated to longitudinal changes in pain intensity.