Course of hand pain over four years in patients with hand osteoarthritis depends on BMI, employment and mental wellbeing: The Hand OSTeoArthritis in Secondary care cohort study.

Abstract

Objective: We aimed to characterize hand osteoarthritis (OA) patients with deteriorating or improving hand pain, and to investigate patients achieving good clinical outcome after four years.

Methods: We used four year annual Australian/Canadian hand osteoarthritis index (AUSCAN) pain subscale (range 0-20) measurements from the HOSTAS cohort (hand OA patients). Pain changes were categorized as deterioration, stable and improvement using the Minimal Clinical Important Improvement (MCII). Good clinical outcome was categorized using the Patient Acceptable Symptom State (PASS). Associations between baseline characteristics (patient and disease characteristics, coping styles, illness perceptions) and outcomes were investigated using multinomial or binary logistic regression, adjusted for baseline pain, age, sex and BMI.

Results: 356 patients (83% female, mean age 60.6 years, mean AUSCAN 9.1) were analyzed. Pain improved for 38%, deteriorated for 30% and remained stable for 32% over four years. Four year pain development followed annual trends. At baseline, 44% of patients reached PASS, 49% at follow-up. Higher BMI, coping through comforting cognitions and illness comprehension were positively associated with pain deterioration. Higher AUSCAN function score, mental wellbeing and illness consequences were negatively associated with pain improvement. Employment (positively) and emotional representations (negatively) were associated with both improvement and deterioration. Higher baseline AUSCAN function, tender joint count and symptoms attributed to hand OA were associated negatively with PASS after four years.

Conclusions: The pain course of hand OA patients is variable, not inevitably worsening, and various factors may play a role. Whether modification of these risk factors can influence pain outcomes requires further investigation.