Comparison of clinical burden between patients with erosive hand osteoarthritis and inflammatory arthritis in symptomatic community-dwelling adults: the Keele clinical assessment studies

Abstract
Objective. To investigate in the general population the clinical impact of erosive OA in interphalangeal joints (IPJs) compared with symptomatic radiographic hand OA and inflammatory arthritis. Methods. Standardized assessments with hand radiographs were performed in participants of two population-based cohorts in North Staffordshire with hand symptoms lasting ≥1 day in the past month. Erosive OA was defined as the presence of an eroded or remodelled phase in ≥1 IPJ using the Verbruggen–Veys method. Radiographic hand OA was defined as the presence of ≥1 IPJ/first carpometacarpal joint with a Kellgren–Lawrence score of ≥2. Diagnoses of inflammatory arthritis were based on medical records. Hand pain and disability were assessed with the Australian/Canadian Hand Osteoarthritis Index (AUSCAN). Linear regression analyses were used to compare clinical determinants between groups and calculate mean differences with 95% CIs, adjusted for age and sex. Results. Of 1076 participants with hand symptoms [60% women, mean age 64.8 years (s.d. 8.3 years)]; 80 persons (7.4%) had erosive OA. The population prevalence of erosive OA in ≥1 IPJ was 2.4% (95% CI 1.8, 3.0). Persons with erosive OA reported more pain and disability than persons with symptomatic radiographic hand OA [adjusted mean difference 1.3 (95% CI 0.3, 2.3) and 2.3 (95% CI 0.4, 4.2), respectively]. Individuals with inflammatory arthritis (n = 44) reported more pain and disability than those with erosive OA [adjusted mean difference 1.7 (95% CI 0.05, 3.4) and 6.3 (95% CI 2.8, 9.9), respectively]. Conclusion. While erosive OA has a greater impact than symptomatic radiographic hand OA in the general population, it is not as severe in terms of hand pain and disability as inflammatory RA.