Background/Purpose: Rheumatoid arthritis (RA) is a chronic, inflammatory disease with symptoms such as pain, severe fatigue, depression and activity limitation. Pain and activity limitation are known to increase the risk of developing fear-avoidance behavior but their associations with physical activity are not fully verified. RA is a chronic disease that people have to live with for many years but knowledge on how fear-avoidance develops over time is still scarce. The aim of the study was to identify and describe groups with different trajectories of fear-avoidance beliefs over 2 years and to identify predictors for each trajectory in people with RA.

Methods: A sample of 2569 people with RA (mean age 58, 77% women) was identified via the Swedish Rheumatology Quality Registers. They responded, at baseline and at 1-year and 2-year follow-ups, to a valid questionnaire on demographics (age, gender, number of children and adults in household, education, income) health-enhancing physical activity (HEPA, current and maintained), disease-related factors (co-morbidity, perceived health, pain, fatigue, activity limitation) and psychosocial matters (fear-avoidance beliefs, anxiety/depression and self-efficacy for exercise). Data were analyzed with k-means longitudinal cluster analysis to identify trajectories of fear-avoidance beliefs and multinomial logistic regression to identify predictors of each trajectory.  

Results: Three stable trajectories of fear-avoidance beliefs were identified from the cluster analysis; one with low (n = 1060) fear-avoidance beliefs, one with moderate (n = 1043) and one with high (n = 466). Predictors of stable high fear-avoidance beliefs, compared to low or moderate levels, were male gender, below average income, current physical activity below HEPA levels and high activity limitation. Additional predictors of high fear-avoidance beliefs compared to low were below-university education, high pain, moderate activity limitation and low self-efficacy for exercise (Table 1).

Conclusion: There are 3 stable trajectories of fear-avoidance behavior in people with RA. The strongest modifiable predictors of persistently high fear-avoidance beliefs are more pronounced activity limitation, pain, below HEPA levels and low self-efficacy for exercise. These factors are important to identify at an early stage in people with RA in order to develop strategies to prevent high fear-avoidance behavior. Table 1. Baseline predictors of trajectories with high (n = 466) vs low (n = 1060) and moderate (n = 1043) fear/avoidance beliefs. Odds ratios (OR) and 95% confidence intervals (CI). Bold figures indicate significant predictors (p < 0.01).  

^aHigh values indicate worse health HEPA = Health-enhancing physical activity VAS = Visual analogue scale HAQ = Stanford Health Assessment Questionnaire EuroQoL = Euro quality of life ESES = Exercise self-efficacy scale