To explore factors related to hand pain in persons with radiographic hand osteoarthritis (OA).
Persons in the Musculoskeletal Pain in Ullensaker Study with radiographic hand OA (≥1 joint with Kellgren/Lawrence grade ≥2) were included (n = 530). We examined the cross-sectional association between possible explanatory variables and hand pain in the entire sample and in 2 hand OA phenotypes (erosive versus nonerosive) using structural equation analyses. Outcome variables were the Australian/Canadian Hand Osteoarthritis Index (AUSCAN; range 0-20) and number of tender finger joints upon palpation (NTJ; range 0-30).
The mean age was 65 years (40-79 years) and 375 participants were women (71%). Diabetes mellitus, female sex, lower education status, familial OA, infrequent alcohol drinking, widespread pain, poor mental health, and higher number of finger joints with ultrasound-detected synovitis and radiographic OA were related to more hand pain in the entire sample. Stratified analyses showed that diabetes mellitus was strongly associated with AUSCAN pain (B-unstandardized coefficient = 3.81 [95% confidence interval (95% CI) 2.27, 5.35]) and NTJ (B-unstandardized coefficient = 4.16 [95% CI 2.01, 6.31]) in erosive hand OA only. In nonerosive OA, lower education status, having familial OA, and poor mental health were associated with hand OA pain. Widespread pain was associated with both outcomes in both phenotypes.
Structural and inflammatory OA changes as well as demographic factors, psychosocial factors, and diabetes mellitus were associated with pain in hand OA. The strong association between diabetes mellitus and pain in erosive hand OA should be further explored.