Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register

AIM: To examine the associations between individual- and disease-related factors and the odds of reaching a clinically relevant pain reduction in people with knee and/or hip osteoarthritis (OA) who underwent a first-line self-management program. MATERIALS AND METHODS: An observational registry-based study including people with knee (n = 18,871) and hip (n = 7,767) OA who participated in a self-management program including education and exercise and had data recorded in the Better Management of patients with Osteoarthritis (BOA) register. We used multivariable logistic regression models to study the association between sex, age, body mass index (BMI), education, comorbidity, pain frequency, walking difficulties, willingness to undergo surgery and the odds of reaching a clinically relevant pain reduction (decrease of >33% on a 0–10 NRS scale) 3 and 12 months after the intervention. All analyses were stratified by joint (knee/hip). RESULTS: Both in the short- and long-term follow-up, a younger age (18–65 years), a lower BMI (< 25), a higher level of education (university), the absence of comorbidities impacting the ability to walk, less frequent pain and not being willing to undergo surgery were associated with higher odds of reaching a clinically relevant pain reduction in people with knee OA. We found similar results for people with hip OA, but with larger uncertainty in the estimates (wider 95% CI). CONCLUSION: Our study suggests that early fist line self-management interventions delivered when people have unilateral hip or knee OA with less frequent pain and are unwilling to undergo surgery, may be important for reaching a clinically relevant pain reduction after participation. Providing the most appropriate treatment to the right patient at the right time is a step in reducing the burden of OA for society and the patient.